WorldWideScience

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. Low Coherence Optic Source Characterization

    International Nuclear Information System (INIS)

    This work presents the results of characterization of the coherence length of an optic source using interferometric techniques and digital signal processing. Optic sources are not ideal because of random behavior in the emission process and spectral dispersion. Optical coherence is the ability of light to generate interference, either temporal or spatial. In time domain, coherence is expressed by the autocorrelation function. In case of monochromatic laser, it has larger coherence length, in the order of tenths to hundredth of meters, rather than a superluminiscent diode (SLD), which is shorter, in the orders of millimeters. This work presents a method for measuring coherence length using an automated Michelson interferometer and a SLD with central wavelength λ0 = 1302.4 nm and acquisition system.by means of a soundcard in a personal computer

  3. Source characterization of Purnima Neutron Generator (PNG)

    International Nuclear Information System (INIS)

    The use of 14.1 MeV neutron generators for the applications such as elemental analysis, Accelerated Driven System (ADS) study, fast neutron radiography requires the characterization of neutron source i.e neutron yield (emission rate in n/sec), neutron dose, beam spot size and energy spectrum. In this paper, a series of experiments carried out to characterize this neutron source. The neutron source has been quantified with neutron emission rate, neutron dose at various source strength and beam spot size at target position

  4. Wind turbine noise source characterization

    International Nuclear Information System (INIS)

    Wind turbine noise is a function of many parameters. Aerodynamics noise is a direct function of the rotor characteristics and wind speed, which can change rapidly with time. Mechanical noise is primarily a function of electrical power output, but the radiation of such noise is highly modified by vibration behaviour within the turbine. An experiment has been performed to isolate the behaviour of the major WTG noise sources with respect to electrical power output and wind speed. Twelve ground based microphones equispaced around the turbine gave detailed noise directionality information. Additional instrumentation was added to allow the separation of aerodynamic and mechanical noise components. Noise was found to be very well correlated to electrical power output. (author)

  5. Statistical Characterization of the Chandra Source Catalog

    CERN Document Server

    Primini, Francis A; Davis, John E; Nowak, Michael A; Evans, Ian N; Glotfelty, Kenny J; Anderson, Craig S; Bonaventura, Nina R; Chen, Judy C; Doe, Stephen M; Evans, Janet D; Fabbiano, Giuseppina; Galle, Elizabeth C; Gibbs, Danny G; Grier, John D; Hain, Roger M; Hall, Diane M; Harbo, Peter N; Xiangqun,; He,; Karovska, Margarita; Kashyap, Vinay L; Lauer, Jennifer; McCollough, Michael L; McDowell, Jonathan C; Miller, Joseph B; Mitschang, Arik W; Morgan, Douglas L; Mossman, Amy E; Nichols, Joy S; Plummer, David A; Refsdal, Brian L; Rots, Arnold H; Siemiginowska, Aneta; Sundheim, Beth A; Tibbetts, Michael S; Van Stone, David W; Winkelman, Sherry L; Zografou, Panagoula

    2011-01-01

    The first release of the Chandra Source Catalog (CSC) contains ~95,000 X-ray sources in a total area of ~0.75% of the entire sky, using data from ~3,900 separate ACIS observations of a multitude of different types of X-ray sources. In order to maximize the scientific benefit of such a large, heterogeneous data-set, careful characterization of the statistical properties of the catalog, i.e., completeness, sensitivity, false source rate, and accuracy of source properties, is required. Characterization efforts of other, large Chandra catalogs, such as the ChaMP Point Source Catalog (Kim et al. 2007) or the 2 Mega-second Deep Field Surveys (Alexander et al. 2003), while informative, cannot serve this purpose, since the CSC analysis procedures are significantly different and the range of allowable data is much less restrictive. We describe here the characterization process for the CSC. This process includes both a comparison of real CSC results with those of other, deeper Chandra catalogs of the same targets and e...

  6. Concretes characterization for spent radioactive sources

    International Nuclear Information System (INIS)

    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)

  7. 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)

  8. 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.

  9. Characterization of the pulse plasma source

    International Nuclear Information System (INIS)

    Characterization of the pulse plasma source through the determination of the local thermodynamic equilibrium (LTE) threshold is described. The maximum electron density measured at the peak in discharge current is determined by the width of the He II Paschen alpha spectral line, and the electron temperature is determined from the ratios of the relative intensities of spectral lines emitted from successive ionized stages of atoms. The electron density and temperature maximum values are measured to be 1.3 x 1017 cm-3 and 19 000 K, respectively. These are typical characteristics for low-pressure, pulsed plasma sources for input energy of 15.8 J at 130 Pa pressure in helium-argon mixture. The use of LTE-based analysis of the emission spectra is justified by measurement of the local plasma electron density at four positions in the discharge tube using a floating hairpin resonance probe. The hairpin resonance probe data are collected during the creation and decay phases of the pulse. From the spatio-temporal profile of the plasma density a 60 μs time-window during which LTE exists throughout the entire plasma source is determined

  10. 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.

  11. Characterization of strong 241Am sources

    International Nuclear Information System (INIS)

    Gamma ray spectra of strong 241Am sources may reveal information about the source composition as there may be other radioactive nuclides such as progeny and radioactive impurities present. In this work the possibility to use gamma spectrometry to identify inherent signatures in 241Am sources in order to differentiate sources from each other, is investigated. The studied signatures are age, i.e. time passed since last chemical separation, and presence of impurities. The spectra of some sources show a number of Doppler broadened peaks in the spectrum which indicate the presence of nuclear reactions on light elements within the sources. The results show that the investigated sources can be differentiated between by age and/or presence of impurities. These spectral features would be useful information in a national nuclear forensics library (NNFL) in cases when the visual information on the source, e.g. the source number, is unavailable. - Highlights: • Age and impurities can be used as a signature for 241Am sources. • Nuclear reactions take place in sources with low Z impurities. • Some sources contain 243Am as an impurity

  12. 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

  13. 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.

  14. Characterization of radioactive orphan sources by gamma spectrometry

    International Nuclear Information System (INIS)

    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 (137Cs) 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)

  15. Intracerebral source generators characterizing concentrative meditation.

    Science.gov (United States)

    Lavallee, Christina F; Hunter, Mathew D; Persinger, Michael A

    2011-05-01

    Previous researchers have studied meditation practices as a means to understand consciousness as well as altered states of consciousness. Various meditation techniques, such as Transcendental Meditation (TM) and Qigong, have been explored with source localization tools; however, the concentrative meditation technique has yet to be fully studied in this manner. The current study demonstrates findings, which outline differential activation in a self-referential default network during meditation in participants who espouse themselves as regular concentrative meditation practitioners, as well as comparisons with a control group practicing a modified version of the relaxation response. The results are compared with other putative experimental findings employing other meditation techniques, and the findings outlined in the current study are discussed with respect to changes in perceptual awareness often reported by meditators. PMID:21350845

  16. 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.

  17. 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.

  18. 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.

  19. Overview of ion source characterization diagnostics in INTF

    International Nuclear Information System (INIS)

    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

  20. Performance characterization of rf-driven multicusp ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Perkins, L.T.; De Vries, G.J.; Herz, P.R.; Kunkel, W.B.; Leung, K.N.; Pickard, D.S.; Wengrow, A.; Williams, M.D. [Lawrence Berkeley National Laboratory, University of California at Berkeley, Berkeley, California 94720 (United States)

    1996-03-01

    Radio-frequency (rf)-driven multicusp ion sources have been developed extensively at Lawrence Berkeley National Laboratory (LBNL) for many applications, each requiring specific source designs. These uses have ranged from large ion sources for neutral-beam injectors{emdash}several tens of centimeters in size{emdash}to small sources for oil-well logging neutron tubes{emdash}a few centimeters in diameter. The advantages associated with internal antenna, rf-driven ion sources include reliability, long component life, ease of operation, and the ability to generate plasmas free of the impurities commonly found in hot-filament discharge sources. We have investigated and characterized the performance of rf-driven sources with respect to the rf operating frequency and ion source size for hydrogen ion species and current density. Furthermore, we have included in this study the aspects of proper coupling of the rf generator to the antenna through an impedance matching network. Finally, critical issues pertaining to general rf operation including beam extraction, rf shielding, and cooling of transformer cores are discussed.

  1. Primary inoculum sources and characterization of Norwegian Phytophthora infestans

    OpenAIRE

    Sharma, Shiva Shankar

    2013-01-01

    Late blight caused by Phytophthora infestans (Mont.) de Barry is a major constrain to potato production in Norway. To characterize present populations of P. infestans and to find potential inoculum sources for early epidemics of late blight in Norway, P. infestans infected samples were collected from 10 different farms of Norway. 237 plant samples were collected in early epidemic. At least 68 recovered isolates from leaf samples were used for testing of their mating type, metalaxyl and propam...

  2. 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

  3. Stress Wave Source Characterization: Impact, Fracture, and Sliding Friction

    Science.gov (United States)

    McLaskey, Gregory Christofer

    Rapidly varying forces, such as those associated with impact, rapid crack propagation, and fault rupture, are sources of stress waves which propagate through a solid body. This dissertation investigates how properties of a stress wave source can be identified or constrained using measurements recorded at an array of sensor sites located far from the source. This methodology is often called the method of acoustic emission and is useful for structural health monitoring and the noninvasive study of material behavior such as friction and fracture. In this dissertation, laboratory measurements of 1--300 mm wavelength stress waves are obtained by means of piezoelectric sensors which detect high frequency (10 kHz--3MHz) motions of a specimen's surface, picometers to nanometers in amplitude. Then, stress wave source characterization techniques are used to study ball impact, drying shrinkage cracking in concrete, and the micromechanics of stick-slip friction of Poly(methyl methacrylate) (PMMA) and rock/rock interfaces. In order to quantitatively relate recorded signals obtained with an array of sensors to a particular stress wave source, wave propagation effects and sensor distortions must be accounted for. This is achieved by modeling the physics of wave propagation and transduction as linear transfer functions. Wave propagation effects are precisely modeled by an elastodynamic Green's function, sensor distortion is characterized by an instrument response function, and the stress wave source is represented with a force moment tensor. These transfer function models are verified though calibration experiments which employ two different mechanical calibration sources: ball impact and glass capillary fracture. The suitability of the ball impact source model, based on Hertzian contact theory, is experimentally validated for small (˜1 mm) balls impacting massive plates composed of four different materials: aluminum, steel, glass, and PMMA. Using this transfer function approach

  4. Characterization of the permanent magnet based hydrogen helicon plasma source for ion source application

    International Nuclear Information System (INIS)

    The helicon wave plasma (HWP) sources have been found to produce higher density plasmas compared to standard capacitively coupled plasma (CCP) or inductively coupled plasma (ICP) and can be of great importance for ion source development. Due to highly efficient nature of helicon plasma sources, they are also being used in the fields of plasma processing and space exploration. A permanent ring magnet based Helicon plasma source using hydrogen gas has been developed on the basis of the optimized design. The uniqueness of the design is having minimum auxiliary interfaces like cooling system and electrical power system, which are normally required for electromagnet based HWP. In the present configuration, the permanent magnet, instead of electromagnet provides the necessary axial magnetic field. The plasma is generated with the help of a single loop, m = 0 antenna using a 13.56 MHz, 1.2 kW source. To characterize the HWP few diagnostic systems are incorporated and used in the experiment which includes a double Langmuir probe for the density measurements and a B-dot probe for identifying the helicon mode by measuring the helicon wave magnetic field. The paper will describe the experimental system and report the experimental characterization data. (author)

  5. 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).

  6. 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.

  7. Dosimetric characterization of interstitial radiotherapy sources: application to iridium 192

    International Nuclear Information System (INIS)

    192Ir interstitial radiotherapy sources have been characterized in terms of normal kerma-rate in air ksub(n), with an air-filled graphite cavity chamber of known volume, thus leading to primary standards. The distribution of absorbed dose in water has been studied, at different depths in a phantom, with an intracavitary chamber and with lithium fluoride thermoluminescent dosemeters. These two experimental investigations, complemented with the establishment of a rigorous formalism, made it possible to determine the transmission function phi(d) in water, which is used in calculation codes for interstitial therapy. The values thus obtained are then compared to these previously published

  8. 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)

  9. 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)

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. High Fluence Neutron Source for Nondestructive Characterization of Nuclear Waste

    International Nuclear Information System (INIS)

    We are addressing the need to measure nuclear wastes, residues, and spent fuel in order to process these for final disposition. For example, TRU wastes destined for the WIPP must satisfy extensive characterization criteria outlined in the Waste Acceptance Criteria, the Quality Assurance Program Plan, and the Performance Demonstration Plan. Similar requirements exist for spent fuel and residues. At present, no nondestructive assay (NDA) instrumentation is capable of satisfying all of the PDP test cycles (particularly for Remote-Handled TRU waste). One of the primary methods for waste assay is by active neutron interrogation. We plan to improve the capability of all active neutron systems by providing a higher intensity neutron source (by about a factor of 1,000) for essentially the same cost, power, and space requirements as existing systems. This high intensity neutron source will be an electrostatically confined (IEC) plasma device. The IEC is a symmetric sphere that was originally developed in the 1950s as a possible fusion reactor. It operates as D-T neutron generator. Although it was not believed to scale to fusion reactor levels, these experiments demonstrated a neutron yield of 2 x 1010 neutrons/second on table-top experiments that could be powered from ordinary laboratory circuits (10 kilowatts). Subsequently, the IEC physics has been extensively studied at the University of Illinois and other locations. We have established theoretically the basis for scaling the output up to 1x1011 neutrons / second. In addition, IEC devices have run for cumulative times approaching 10,000 hours, which is essential for practical application to NDA. They have been operated in pulsed and continuous mode. The essential features of the IEC plasma neutron source, compared to existing sources of the same cost, size and power consumption, are: Table 1: Present and Target Operating Parameters for Small Neutron Generators Parameter Present IEC Target or Already Proven Neutron Yield

  16. 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

  17. 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

  18. 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

  19. Multiple line arrays for the characterization of aeroacoustic sources using a time-reversal method.

    Science.gov (United States)

    Mimani, A; Doolan, C J; Medwell, P R

    2013-10-01

    This letter investigates the use of multiple line arrays (LAs) in a Time-Reversal Mirror for localizing and characterizing multipole aeroacoustic sources in a uniform subsonic mean flow using a numerical Time-Reversal (TR) method. Regardless of the original source characteristics, accuracy of predicting the source location can be significantly improved using at least two LAs. Furthermore, it is impossible to determine the source characteristics using a single LA, rather a minimum of two are required to establish either the monopole or dipole source nature, while four LAs (fully surrounding the source) are required for characterizing a lateral quadrupole source. PMID:24116538

  20. Characterization of the proton ion source beam for the high intensity neutrino source at Fermilab

    Science.gov (United States)

    Tam, Wai-Ming

    Fermilab is considering an 8 GeV superconducting H-- linac with the primary mission of enabling 2MW beam power from the 120 GeV Fermilab Main Injector for a neutrino program. The High Intensity Neutrino Source (HINS) R&D program is underway to demonstrate the technical feasibility in a 30MeV prototype linac. The HINS Linac Front-end is composed of an ion source, a radio frequency quadrupole (RFQ), a medium energy beam transport and 16 room temperature Crossbar H-type cavities that accelerate the beam to 10 MeV. The cavities are separated by superconducting solenoids enclosed in individual cryostats. Beyond 10 MeV, the design uses superconducting spoke resonators. Recently, the HINS proton ion source has been successfully commissioned. It produces a 50 keV, 3 msec pulsed beam with a peak current greater than 20mA at 2.5 Hz. The beam is transported to the RFQ by a low energy beam transport (LEBT) that consists of two focusing solenoids, four steering dipole magnets and a beam current transformer. To understand beam transmission through the RFQ, it is important to characterize the 50 keV beam before connecting the LEBT to the RFQ. A wire scanner and a Faraday cup are temporarily installed at the exit of the LEBT to study the beam parameters. All beam studies are based on data taken using the wire scanner. We start with interpreting the signal measured by the wire scanner. Then, we performed a beam-calibration to the steering dipole magnets. We then study transverse motion coupling due to solenoidal field by measuring beam rotation through solenoid. Analysis to these measurements is accompanied with beam physics modeling and particle tracking simulation. Also, transverse emittance was measured using two different methods and results are compared. Finally, a bunch shape monitor will be introduced. It is a high bandwidth instrumentation device that measures the longitudinal profile of a bunched proton/H- beam. HINS will use it for its 2.5MeV beam. Operational principle

  1. 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

  2. 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.

  3. 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...

  4. 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)

  5. Characterization and indentification of air pollution sources in Metro Manila

    International Nuclear Information System (INIS)

    Air particulates matter (PM10 and PM2.5) is a mixture of different pollutant sources which can be of anthropogenic and/or natural origin. Identification and apportionment of pollutant sources is important to be able to have better understanding of prevailing conditions in the area and thus better air quality management can be applied. Results have shown that in all the sampling sites, a major fraction of pollutant sources come from vehicular or traffic-oriented sources, comprising more than 30% of PM2.5. Of particular great concern especially in the residents of the area are the high Pb levels in Valenzuela City. In 2005, the annual mean level of PM10 Pb in Valenzuela was 0.267 μg/m3 while the other PNRI sampling sites registered annual mean levels between 0033 to 0.085 μ/m3. The high Pb condition is reflected in the source apportionment studies with Pb sources showing up in both the coarse (PM10-2.5) and the fine fractions (PM2.5). The CPF analysis plots of 2008 Pb levels in both the coarse and the fine fractions show patterns for probable sources in 2008. Further study of the location of battery recycling facilities and other possible sources of lead is needed to validate the results of the CPF determination. (author)

  6. Photon statistics characterization of a single-photon source

    International Nuclear Information System (INIS)

    In a recent experiment, we reported the time-domain intensity noise measurement of a single-photon source relying on single-molecule fluorescence control. In this paper, 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 ON↔OFF dynamics. Finally, source intensity noise analysis, using the Mandel parameter, is quantitatively compared with the usual approach relying on the time autocorrelation function, both methods yielding the same molecular dynamical parameters

  7. 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...

  8. Prototype portal monitor characterization using source Cs137

    International Nuclear Information System (INIS)

    Initial testing has been conducted on the prototype portal monitors using Cs137 source type 250 milli Curie. These tests include testing of the remote control system through the internet and the data acquisition system on a prototype portal monitors. The purpose of testing is to determine the performance of the control and data acquisition system to obtain the expected image. The test results show that the control system of portal monitors can be operated and controlled through the internet. The test results show that the data acquisition system acquisition system can produce 2-dimensional image although not satisfactory, this is caused by the possibility of a small source activity. On further research will be tested using a larger source of Cs137 500 milli-Curie. (author)

  9. 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

  10. 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.

  11. Characterization of near-source ground motions with earthquake simulations

    OpenAIRE

    Aagaard, Brad T.; Hall, John F.; Heaton, Thomas H.

    2001-01-01

    We examine the characteristics of long-period near-source ground motions by conducting a sensitivity study with variations in six earthquake source parameters for both a strike-slip fault (M 7.0-7.1) and a thrust fault (M 6.6-7.0). The directivity of the ruptures creates large displacement and velocity pulses in the forward direction. The dynamic displacements close to the fault are comparable to the average slip. The ground motions exhibit the greatest sensitivity to the fault depth with mod...

  12. Characterization of a neutron source of 239PuBe

    International Nuclear Information System (INIS)

    The spectrum equivalent dose and environmental equivalent dose f a 239PuBe 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 6LiI(Eu) scintillator obtaining the count rates that produce, to a distance of 100 cm, a 239PuBe 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)

  13. Dosimetric characterization of a brachytherapy source for gynaecological applications

    International Nuclear Information System (INIS)

    In this work Monte Carlo calculations and experimental measurements of dose rate in water per unit air-kerma strength, D/Sk, of a low dose rate Amersham CDCS.J 137Cs source are reported. The Monte Carlo calculations included a detailed simulation of the geometric structure of the source embedded in a water medium. The experimental procedure included the construction of a lucite phantom with the same geometric characteristics as the one used in the simulation. Dose measurements were performed using high spatial resolution RadioChromic dye film and TL dosemeters for short and large distances from the source, respectively. The comparison between simulated and reported values in the literature of D/Sk for the same source are of 1.0% in average [1]. The differences between the TL measurements and the simulation also are of 1% in average, while the difference between the MC and the RadioChromic film are larger, particularly when the RadioChromic film received doses smaller than 7 Gy

  14. 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

  15. 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

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

    International Nuclear Information System (INIS)

    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

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

    CERN Document Server

    Ghetti, R; Helgesson, J; De Filippo, E; Tagliente, G; Anzalone, A; Bellini, V; Carlén, L; Cavallaro, S; Celano, L; D'Erasmo, G; Di Santo, D; Fiore, E M; Fokin, A; Geraci, M; Jakobsson, B; Kuznetsov, A; Lanzanò, G; Mahboub, D; Murin, Yu A; 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

    1999-01-01

    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.

  18. 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.

  19. Characterization of photon-emitting wide area reference sources

    International Nuclear Information System (INIS)

    A procedure has been developed to calibrate photon-emitting wide area reference sources in terms of activity, surface emission rate and uniformity considering the requirements introduced by the recent revision of ISO standard 8769. The method makes use of a large volume NaI detector with a cross table scanning system, a radiography system and it applies Monte Carlo techniques to assess the surface emission rate. The method was successfully applied to sources of 241Am, 57Co, 137Cs and 60Co. In addition, problems with definitions and the practical use of standard are highlighted. - Highlights: ► A procedure to calibrate photon-emitting wide area reference sources has been developed. ► The requirements introduced by the recent revision of ISO standard 8769 are discussed. ► A Monte Carlo approach is used to calculate the photon flux for a given activity distribution. ► The position dependent efficiency map of a large NaI detector is measured by a motorized XY stage. ► The uniformity of the activity distribution is reconstructed from a digital autoradiography.

  20. 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.

  1. Groundwater Pollution Source Characterization of an Old Landfill

    DEFF Research Database (Denmark)

    Kjeldsen, Peter

    Only a few landfill investigations have focused on both the quantity and the quality of leachate as a source of groundwater pollution. The investigation of Vejen Landfill in Denmark included an introductionary historical survey (old maps, aerial photographs, interviews, etc.), leachate quality...... drainage ditch and a southerly leach to the secondary aquifer were taking place. To evaluate the proportion of leachate discharging to the drainage ditch, piezometers were installed in the shallow leachate-affected aquifer. On the basis of several soundings, the groundwater surface was mapped and the...

  2. Source-trap characterization of thermally transferred OSL in quartz

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Z X [Department of Earth and Environmental Sciences, Tulane University, New Orleans, LA 70118 (United States); Mauz, B; Lang, A, E-mail: zshen@tulane.edu, E-mail: mauz@liverpool.ac.uk, E-mail: lang@liverpool.ac.uk [Department of Geography, University of Liverpool, Liverpool, L69 7ZT (United Kingdom)

    2011-07-27

    Thermally transferred optically stimulated luminescence (TT-OSL) of quartz is the low intensity OSL measured after heating a previously optically zeroed quartz to temperatures below that erasing the OSL electron trap. We identify the source traps contributing to TT-OSL by studying the changes in TT-OSL and thermoluminescence (TL) caused by optical bleaching at various temperatures and by repeated TT-OSL measurements, and quantify source-trap parameters using the Hoogenstraaten method. We find that both the single transfer mechanism and the double transfer mechanism are contributing to TT-OSL production. Three source traps are identified when the samples are heated to 300 deg. C for 10 s to induce the thermal transfer. The first one corresponds to a TL peak at {approx}200 deg. C. It captures electrons during the optical bleaching and releases these charges during subsequent heating. It provides {approx}10% of the electrons that give rise to TT-OSL. The second trap corresponds to a TL peak at 290-300 deg. C and provides {approx}80% of the electrons for TT-OSL through the single transfer mechanism. This electron trap has a depth of 1.34 {+-} 0.05 eV and a frequency factor in the order of 10{sup 11} s{sup -1}. It has a mean lifetime of 0.24 Ma at 10 deg. C. The third trap corresponds to a TL peak at {approx}380 deg. C and provides {approx}10% electrons for TT-OSL through the single transfer mechanism. It has a depth of 1.66 {+-} 0.07 eV and a frequency factor in the order of 10{sup 12} s{sup -1}. To validate the techniques used we also determined the parameters of the fast component OSL trap and received results consistent with published values. Most importantly, our results show that the relatively short lifetime of the main TT-OSL source trap limits possibilities of using TT-OSL to extend the age range of quartz OSL dating, as has been suggested by various authors.

  3. Source-trap characterization of thermally transferred OSL in quartz

    Science.gov (United States)

    Shen, Z. X.; Mauz, B.; Lang, A.

    2011-07-01

    Thermally transferred optically stimulated luminescence (TT-OSL) of quartz is the low intensity OSL measured after heating a previously optically zeroed quartz to temperatures below that erasing the OSL electron trap. We identify the source traps contributing to TT-OSL by studying the changes in TT-OSL and thermoluminescence (TL) caused by optical bleaching at various temperatures and by repeated TT-OSL measurements, and quantify source-trap parameters using the Hoogenstraaten method. We find that both the single transfer mechanism and the double transfer mechanism are contributing to TT-OSL production. Three source traps are identified when the samples are heated to 300 °C for 10 s to induce the thermal transfer. The first one corresponds to a TL peak at ~200 °C. It captures electrons during the optical bleaching and releases these charges during subsequent heating. It provides ~10% of the electrons that give rise to TT-OSL. The second trap corresponds to a TL peak at 290-300 °C and provides ~80% of the electrons for TT-OSL through the single transfer mechanism. This electron trap has a depth of 1.34 ± 0.05 eV and a frequency factor in the order of 1011 s-1. It has a mean lifetime of 0.24 Ma at 10 °C. The third trap corresponds to a TL peak at ~380 °C and provides ~10% electrons for TT-OSL through the single transfer mechanism. It has a depth of 1.66 ± 0.07 eV and a frequency factor in the order of 1012 s-1. To validate the techniques used we also determined the parameters of the fast component OSL trap and received results consistent with published values. Most importantly, our results show that the relatively short lifetime of the main TT-OSL source trap limits possibilities of using TT-OSL to extend the age range of quartz OSL dating, as has been suggested by various authors.

  4. 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.

  5. Characterization of Allergen Emission Sources in Urban Areas.

    Science.gov (United States)

    Cariñanos, Paloma; Adinolfi, Cristiano; Díaz de la Guardia, Consuelo; De Linares, Concepción; Casares-Porcel, Manuel

    2016-01-01

    Pollen released by urban flora-a major contributor to airborne allergen content during the pollen season-has a considerable adverse impact on human health. Using aerobiological techniques to sample and characterize airborne biological particulate matter (BPM), we can identify the main species contributing to the pollen spectrum and chart variations in counts and overall pollen dynamics throughout the year. However, given the exponential increase in the number of pollen allergy sufferers in built-up areas, new strategies are required to improve the biological quality of urban air. This paper reports on a novel characterization of the potential allergenicity of the tree species most commonly used as ornamentals in Mediterranean cities. Values were assigned to each species based on a number of intrinsic features including pollination strategy, pollen season duration, and allergenic capacity as reported in the specialist literature. Findings were used to generate a database in which groups of conifers, broadleaves, and palm trees were assigned a value of between 0 and 36, enabling their allergenicity to be rated as nil, low, moderate, high, or very high. The case study presented here focuses on the city of Granada in southern Spain. The major airborne-pollen-producing species were identified and the allergenicity of species growing in urban green zones was estimated. Corrective measures are proposed to prevent high allergen levels and thus improve biological air quality. PMID:26828180

  6. 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

  7. 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

  8. 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.

  9. 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

  10. Groundwater Pollution Source Characterization of an Old Landfill

    DEFF Research Database (Denmark)

    Kjeldsen, Peter

    1993-01-01

    Only a few landfill investigations have focused on both the quantity and the quality of leachate as a source of groundwater pollution. The investigation of Vejen Landfill in Denmark included an introductionary historical survey (old maps, aerial photographs, interviews, etc.), leachate quality...... analysis, potential mapping of the groundwater surface below the landfill and leachate flow to surface waters and groundwater. The historical investigation showed that the original soil surface beneath the waste was a relatively heterogeneous mixture of boggy ground and sand soil areas. This indicated that...... the leaching from the landfill could be unevenly distributed. The main specific organic compounds observed in the leachate were aromatic hydrocarbons (mainly xylenes), phenols and the pesticide MCPP. Preliminary investigations of the leach from the landfill indicated, that both a northerly leach to a...

  11. Stable isotopes in characterization of moisture sources in precipitation

    International Nuclear Information System (INIS)

    Isotope distributions in precipitation in the Asian Monsoon region and their significance for understanding moisture transport patterns is reviewed. Isotopes in precipitation in southeast Asia, including the ASM region, have more negative delta values in strong summer rains, in spite of higher temperatures compared to the winter rains, and have been interpreted to be controlled primarily by the amount of precipitation and rainout during moisture transport across the continental areas. Stable isotope ratios in precipitation at island or coastal stations located between 70 deg. E - 160 deg. W longitudes and 10 deg. S - 26 deg. N latitudes were obtained from the global network of isotopes in precipitation (GNIP) database. Monitoring stations between 70 deg. E - 96 deg. E, located on the Indian subcontinent and Sri Lanka, display an easterly decrease in δ18O values from -1.3 to -4.3. Precipitation between 100 deg. E - 170 deg. E has much lower δ18O values with no discernible pattern across the longitudinal range. In the western Pacific, between 170 deg. E - 160 deg. W, precipitation δ18O values once again are much greater than those in the 100 deg. E -170 deg. E range. While delta values in the western Pacific stations are similar to those in the 70 deg. E -100 deg. E longitudinal range, they have a much narrower range of values that do not vary with latitude. There is a lack of correlation between δ-values and the amount of precipitation or mean surface air temperature, either within or between the three sub-groups of data. In addition, similar amounts of precipitation in each of the sub-groups have different delta values. The isotope distributions are consistent with the inferred source and transport of moisture in the Asian Summer Monsoon. Indian Ocean and the Bay of Bengal are the primary source of moisture for the Indian subcontinent, resulting in relatively high δ18O values observed in this area. Air circulation in the 100 deg. E - 170 deg. E region is

  12. Production and characterization of a custom-made 228Th source with reduced neutron source strength for the Borexino experiment

    International Nuclear Information System (INIS)

    A custom-made 228Th source of several MBq activities was produced for the Borexino experiment to study the external background of the detector. The aim was to reduce the unwanted neutron emission produced via (α,n) reactions in ceramics typically used for commercial 228Th sources. For this purpose a ThCl4 solution was chemically converted into ThO2 and embedded in a gold foil. The paper describes the production of the custom-made source and its characterization by means of γ-activity, dose rate and neutron source strength measurements. From γ-spectroscopic measurements it was deduced that activity transfer from the initial solution to the final source was >91% (at 68% C.L.) and the final activity was (5.41±0.30) MBq. The dose rate was measured with two dosimeters yielding 12.1 mSv/h and 14.3 mSv/h in 1 cm distance. The neutron source strength of the 5.41 MBq 228Th source was determined to be (6.59±0.85) s−1.

  13. 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

  14. 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.

  15. Robust remediation strategies at gas-work sites: a case of source recognition and source characterization

    International Nuclear Information System (INIS)

    In The Netherlands there have been gasworks at about 260 to 270 locations. Most of these locations are or were heavily polluted with tar, ashes and cyanides and many of them belong to the locations where remediation actions have already been executed. It seems however that many of them also belong to the locations where remediation actions were not quite as successful as was expected. So, for many gas-work sites that were already 'remedied' in the 80's and early 90's of the foregoing century, new programs for site remediation are planned. Of course the mistakes from the past should now be avoided. The current remediation strategy in The Netherlands for gas-work sites can be comprised in four steps: 1 - removing spots in the top soil, 2 - removing spots with mobile components in the shallow subsoil, 3 - controlling spots with mobile components in the deep subsoil, 4 - creating a 'steady endpoint situation' in the plume. At many former gas-work sites real sources, i.e. in a physico-chemical sense, are not very well known. This can easily lead to insufficient removal of some or part of these sources and cause a longer delivery of contaminants to the groundwater plume, with higher endpoint concentrations, higher costs and more restrictions for future use. The higher concentrations and longer deliveries originating from not recognized or not localized sources are often not sufficiently compensated by the proposed plume management in current remediation strategies. Remediation results can be improved by using knowledge about the processes that determine the delivery of contaminants to the groundwater, the materials that cause these delivery and the locations at the site where these are most likely found. When sources are present in the deep subsoil or the exact localization of sources is uncertain, robust remediation strategies should be chosen and wishful thinking about removing sources with in situ techniques should be avoided. Robust strategies are probably less

  16. Verification of source term estimation method against measured data for spent fuel hardware characterization

    International Nuclear Information System (INIS)

    Highlights: ► The Republic of Korea has developed an advanced source term analysis tool, called ASOURCE, to support R and D action plans. ► It is comprised of three analysis sequences for fuel waste, metal waste, and grand source term characterizations. ► The sequence for metal waste characterization was verified by the measured nuclide inventory. ► The calculated values agreed with the measured data within 35%, indicating that ASOURCE supplies viable source term data. - Abstract: The Republic of Korea has developed an advanced source term analysis tool, called ASOURCE, to support R and D action plans for the achievement of an advanced fuel cycle employing a pyroprocess in connection with a sodium-cooled fast reactor. ASOURCE has the following functions: (a) generation of inflow and outflow source terms of mixed spent fuel (SF) in each process for the design of the pyroprocess facility; (b) overall inventory estimation for Transuranics (TRUs) and long-lived nuclides in SFs stored at each or all reactor sites for the design of the SFR; and (c) grand source terms of a batch of SFs with different irradiation and cooling profiles for the practical design of a temporary or interim storage facility of SFs. ASOURCE is comprised of three analysis sequences, a Fuel Waste Characterization Sequence, Metal Waste Characterization Sequence, and Grand Source Term Characterization Sequence. In this study, the Metal Waste Characterization Sequence was verified by comparing the nuclide inventory estimated by ASOURCE with the measured nuclide inventory in an irradiated grid plate. It was found that the values calculated by ASOURCE agreed with the measured data within 35%, indicating that the developed program supplies viable source term data

  17. 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.

  18. Optimal characterization of pollutant sources in contaminated aquifers by integrating sequential-monitoring-network design and source identification: methodology and an application in Australia

    Science.gov (United States)

    Prakash, Om; Datta, Bithin

    2015-09-01

    Often, when pollution is first detected in groundwater, very few spatiotemporal pollutant concentration measurements are available. The contaminant concentration measurement data initially available are generally sparse and insufficient for accurate source characterization. This requires development of a contaminant monitoring plan and its field implementation to collect more data. The location of scientifically chosen monitoring points and the number of measurements are important considerations in improving the source-characterization process, especially in a complex contamination scenario. In order to improve the efficiency of source characterization, a feedback-based methodology is implemented, integrating sequential-monitoring-network design and a source identification method. The simulated annealing (SA) optimization algorithm is used to solve the models for optimal source identification and the monitoring-network-design optimization. This sequence is repeated a few times to improve the accuracy of source characterization. The methodology is based on the premise that concentration measurements from a sequence of implemented monitoring networks provide feedback information on the actual concentration in the site. This additional information, obtained as feedback from monitoring networks designed and implemented based on intermediate source characterization, can result in sequential improvement in the resulting source characterization. The performance of this methodology is evaluated by application to a contaminated aquifer site in New South Wales, Australia, where source location, source-activity initiation time and source-flux (mass per unit time) release history are considered as unknown variables. The performance evaluation results demonstrate potential applicability of the proposed sequential methodology.

  19. Characterization of a alpha particle detector CR-39 exposed to a source of radium

    International Nuclear Information System (INIS)

    In this project, the main goal is the characterization of a alpha particle detector CR-39 exposed to a source of radio. Three detectors were exposed to a source of radium and then chemically treated for different periods. This way, we could analyze these samples and collect the information needed to verify that at least one of the chemical attack, there has been a separation of the energies alpha particles incident with distinct peaks, thus characterizing the CR-39 as alpha spectrometer in the range 2.5 to 6.3 MeV . (author)

  20. 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...

  1. 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.

  2. Multidimensional characterization of an entangled photon-pair source via stimulated emission tomography.

    Science.gov (United States)

    Fang, B; Liscidini, M; Sipe, J E; Lorenz, V O

    2016-05-01

    Using stimulated emission tomography, we characterize an entangled photon-pair source in the energy and polarization degrees of freedom, with a precision far exceeding what could be obtained by quantum state tomography. Through this multidimensional tomography we find that energy-polarization correlations are a cause of polarization-entanglement degradation, demonstrating that this technique provides useful information for source engineering and can accelerate the development of quantum information processing systems dependent on many degrees of freedom. PMID:27137611

  3. 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.

  4. 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.

  5. 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)

  6. Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry

    OpenAIRE

    Daellenbach, K. R.; Bozzetti, C.; A. Křepelová; F. Canonaco; Wolf, R.; P. Zotter; P. Fermo; Crippa, M.; Slowik, J. G.; Y. Sosedova; Y. Zhang; Huang, R.-J.; L. Poulain; S. Szidat; U. Baltensperger

    2016-01-01

    Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS) have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make its deployment at sufficient sites to determine regional characteristics impractical. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the characterization of th...

  7. 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…

  8. 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

  9. 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.

  10. 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)

  11. 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.

  12. 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

  13. 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.

  14. Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry

    OpenAIRE

    Daellenbach, K. R.; Bozzetti, C.; A. Křepelová; F. Canonaco; Wolf, R.; P. Zotter; P. Fermo; Crippa, M.; Slowik, J. G.; Y. Sosedova; Zhang, Yanlin; Huang, R.-J.; L. Poulain; Szidat, Sönke; U. Baltensperger

    2016-01-01

    Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS) have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make its deployment at sufficient sites to determine regional characteristics impractical. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the characterization of their chemical natur...

  15. 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...

  16. Characterizing the Aperiodic Variability of 3XMM Sources using Bayesian Blocks

    Science.gov (United States)

    Salvetti, D.; De Luca, A.; Belfiore, A.; Marelli, M.

    2016-06-01

    I will present Bayesian blocks algorithm and its application to XMM sources, statistical properties of the entire 3XMM sample, and a few interesting cases. While XMM-Newton is the best suited instrument for the characterization of X-ray source variability, its most recent catalogue (3XMM) reports light curves only for the brightest ones and excludes from its analysis periods of background flares. One aim of the EXTraS ("Exploring the X-ray Transient and variable Sky") project is the characterization of aperiodic variability of as many 3XMM sources as possible on a time scale shorter than the XMM observation. We adapted the original Bayesian blocks algorithm to account for background contamination, including soft proton flares. In addition, we characterized the short-term aperiodic variability performing a number of statistical tests on all the Bayesian blocks light curves. The EXTraS catalogue and products will be released to the community in 2017, together with tools that will allow the user to replicate EXTraS results and extend them through the next decade.

  17. 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...... 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 an...... of the FACT field measurements, which allows the conversion of discrete activated carbon concentrations to aqueous concentrations at given hydraulic parameters and FACT parameters. The passive groundwater sampling with snap samplers resulted in significantly different concentration levels and...

  18. 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

  19. TG-43 U1 based dosimetric characterization of model 67-6520 Cs-137 brachytherapy source

    International Nuclear Information System (INIS)

    Purpose: Brachytherapy treatment has been a cornerstone for management of various cancer sites, particularly for the treatment of gynecological malignancies. In low dose rate brachytherapy treatments, 137Cs sources have been used for several decades. A new 137Cs source design has been introduced (model 67-6520, source B3-561) by Isotope Products Laboratories (IPL) for clinical application. The goal of the present work is to implement the TG-43 U1 protocol in the characterization of the aforementioned 137Cs source. Methods: The dosimetric characteristics of the IPL 137Cs source are measured using LiF thermoluminescent dosimeters in a Solid Water phantom material and calculated using Monte Carlo simulations with the GEANT4 code in Solid Water and liquid water. The dose rate constant, radial dose function, and two-dimensional anisotropy function of this source model were obtained following the TG-43 U1 recommendations. In addition, the primary and scatter dose separation (PSS) formalism that could be used in convolution/superposition methods to calculate dose distributions around brachytherapy sources in heterogeneous media was studied. Results: The measured and calculated dose rate constants of the IPL 137Cs source in Solid Water were found to be 0.930(±7.3%) and 0.928(±2.6%) cGy h-1 U-1, respectively. The agreement between these two methods was within our experimental uncertainties. The Monte Carlo calculated value in liquid water of the dose rate constant was Λ=0.948(±2.6%) cGy h-1 U-1. Similarly, the agreement between measured and calculated radial dose functions and the anisotropy functions was found to be within ±5%. In addition, the tabulated data that are required to characterize the source using the PSS formalism were derived. Conclusions: In this article the complete dosimetry of the newly designed 137Cs IPL source following the AAPM TG-43 U1 dosimetric protocol and the PSS formalism is provided.

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

    Science.gov (United States)

    Abad, Sergi; Turon, Xavier

    2015-12-01

    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. PMID:26690180

  1. 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.

  2. 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.

  3. Chemical characterization and source apportionment of fine and coarse particulate matter in Lahore, Pakistan

    Science.gov (United States)

    Stone, Elizabeth; Schauer, James; Quraishi, Tauseef A.; Mahmood, Abid

    2010-03-01

    Lahore, Pakistan is an emerging megacity that is heavily polluted with high levels of particle air pollution. In this study, respirable particulate matter (PM 2.5 and PM 10) were collected every sixth day in Lahore from 12 January 2007 to 19 January 2008. Ambient aerosol was characterized using well-established chemical methods for mass, organic carbon (OC), elemental carbon (EC), ionic species (sulfate, nitrate, chloride, ammonium, sodium, calcium, and potassium), and organic species. The annual average concentration (±one standard deviation) of PM 2.5 was 194 ± 94 μg m -3 and PM 10 was 336 ± 135 μg m -3. Coarse aerosol (PM 10-2.5) was dominated by crustal sources like dust (74 ± 16%, annual average ± one standard deviation), whereas fine particles were dominated by carbonaceous aerosol (organic matter and elemental carbon, 61 ± 17%). Organic tracer species were used to identify sources of PM 2.5 OC and chemical mass balance (CMB) modeling was used to estimate relative source contributions. On an annual basis, non-catalyzed motor vehicles accounted for more than half of primary OC (53 ± 19%). Lesser sources included biomass burning (10 ± 5%) and the combined source of diesel engines and residual fuel oil combustion (6 ± 2%). Secondary organic aerosol (SOA) was an important contributor to ambient OC, particularly during the winter when secondary processing of aerosol species during fog episodes was expected. Coal combustion alone contributed a small percentage of organic aerosol (1.9 ± 0.3%), but showed strong linear correlation with unidentified sources of OC that contributed more significantly (27 ± 16%). Brick kilns, where coal and other low quality fuels are burned together, are suggested as the most probable origins of unapportioned OC. The chemical profiling of emissions from brick kilns and other sources unique to Lahore would contribute to a better understanding of OC sources in this megacity.

  4. 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

  5. Design and Development of an Open Source Software Application for the Characterization of Spatially Variable Fields

    Science.gov (United States)

    Gunnell, D. K.; Osorio-Murillo, C. A.; Over, M. W.; Frystacky, H.; Ames, D. P.; Rubin, Y.

    2013-12-01

    The characterization of the structural parameters of spatially variable fields (SVFs) is essential to understanding the variability of hydrological processes such as infiltration, evapotranspiration, groundwater contaminant transport, etc. SVFs can be characterized using a Bayesian inverse method called Method of Anchored Distributions (MAD). This method characterizes the structural parameters of SVFs using prior information of structural parameter fields, indirect measurements, and simulation models allowing the transfer of valuable information to a target variable field. An example SVF in hydrology is hydraulic conductivity, which may be characterized by head pressure measurements through a simulation model such as MODFLOW. This poster will present the design and development of a free and open source inverse modeling desktop software application and extension framework called MAD# for the characterization of the structural parameters of SVFs using MAD. The developed software is designed with a flexible architecture to support different simulation models and random field generators and includes geographic information system (GIS) interfaces for representing, analyzing, and understanding SVFs. This framework has also been made compatible with Mono, a cross-platform implementation of C#, for a wider usability.

  6. 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.

  7. 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.

  8. Characterization of humins from different natural sources and the effect on microbial reductive dechlorination of pentachlorophenol.

    Science.gov (United States)

    Zhang, Chunfang; Zhang, Dongdong; Xiao, Zhixing; Li, Zhiling; Suzuki, Daisuke; Katayama, Arata

    2015-07-01

    Humins have been reported to function as an electron mediator for microbial reducing reactions. However, the physicochemical properties and the functional moieties of humins from different natural sources have been poorly characterized. In this study, humins extracted from seven types of soil and from a river sediment were examined on the effect on microbial reductive dechlorination of pentachlorophenol (PCP) and characterized polyphasically. All humins facilitated microbial reductive dechlorination of PCP as electron mediators using formate as carbon source, with different dechlorination rates ranging from 0.99 to 7.63 (μmol Cl-) L(-1) d(-1). The highest rates were observed in humins with high carbon contents, extracted from Andisols containing allophone as major clay. Yields of the humins and the elemental compositions varied among sources. Fourier transform infrared analysis showed that all the humins exhibited similar spectra with different absorbance intensity; these data are indicative of their similar structures and identical classes of functional groups. The electron spin resonance spectra of humins prepared at different pH showed typical changes for the semiquinone-type radicals, suggestive of quinone moieties for the redox activity of the humins. Cyclic voltammetry analysis confirmed the presence of redox-active moieties in all the humins, with the estimated redox potentials in the range of -0.30 to -0.13 V (versus a standard hydrogen electrode), falling into the range of standard redox potential between the oxidation of formate as electron donor and the initial dechlorination of PCP as electron acceptor. PMID:25819981

  9. 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...

  10. SWISSCASE: development and characterization of an electron cyclotron resonance ion source for the calibration of space flight instruments

    OpenAIRE

    Bodendorfer, Michael; Shea, Herbert; Altwegg, Kathrin

    2008-01-01

    This PhD thesis consists of planning, simulating, building, testing and characterizing a new electron cyclotron resonance (ECR) ion source, SWISSCASE. the Solar Wind Ion Source Simulator for the CAlibration of Space Experiments located at the University of Bern, Switzerland. The ion source will be operated in the existing CASYMS ultra high vacuum (UHV) facility and will extend the application field of the existing filament electron collision ion source inside CASYMS and the existing electron ...

  11. 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...

  12. Methodology and main results of seismic source characterization for the PEGASOS Project, Switzerland

    International Nuclear Information System (INIS)

    Under the direction of the National Cooperative for the Disposal of Radioactive Waste (NAGRA), a probabilistic seismic hazard analysis was conducted for the Swiss nuclear power plant sites. The study has become known under the name 'PEGASOS Project'. This is the first of a group of papers in this volume that describes the seismic source characterization methodology and the main results of the project. A formal expert elicitation process was used, including dissemination of a comprehensive database, multiple workshops for identification and discussion of alternative models and interpretations, elicitation interviews, feedback to provide the experts with the implications of their preliminary assessments, and full documentation of the assessments. A number of innovative approaches to the seismic source characterization methodology were developed by four expert groups and implemented in the study. The identification of epistemic uncertainties and treatment using logic trees were important elements of the assessments. Relative to the assessment of the seismotectonic framework, the four expert teams identified similar main seismotectonic elements: the Rhine Graben, the Jura / Molasse regions, Helvetic and crystalline subdivisions of the Alps, and the southern Germany region. In defining seismic sources, the expert teams used a variety of approaches. These range from large regional source zones having spatially-smoothed seismicity to smaller local zones, to account for spatial variations in observed seismicity. All of the teams discussed the issue of identification of feature-specific seismic sources (i.e. individual mapped faults) as well as the potential reactivation of the boundary faults of the Permo-Carboniferous grabens. Other important seismic source definition elements are the specification of earthquake rupture dimensions and the earthquake depth distribution. Maximum earthquake magnitudes were assessed for each seismic source using approaches that consider the

  13. Source potential and sequence stratigraphic characterization of microbial evaporitic mudrocks: Upper Permian Zechstein Group, Northern Germany

    Science.gov (United States)

    Hammes, Ursula; Mutti, Maria

    2013-04-01

    Microbial evaporitic carbonate mudrocks are important source rocks throughout much of the earth history. Some of the largest hydrocarbon provinces are potentially sourced by evaporite source rocks such as the Cretaceous and Jurassic in the Middle East, the Tertiary in Spain, the Permian in northern Germany, the Devonian in Canada, and the Pennsylvanian in the USA. Carbonate mudrocks deposited under mesosaline conditions are often over-looked and dismissed as potential source rocks. However, preservation and accumulation of organic matter in salinity-layered intraplatform epeiric depressions and restricted basin centers are significant. These mudrocks may not only constitute the source but also exhibit reservoir qualities. Slope and basin laminated mudrocks were investigated for their source and reservoir potential using sequence stratigraphic and geochemical techniques to investigate the exploration potential of the northern German Upper Permian Zechstein Formation. The lower Zechstein cycles Z1 and Z2 are characterized by calcareous to argillaceous, laminated, organic-rich mudstones with TOC (total organic carbon) contents ranging mostly 6% in the Z1 cycle. Maturities range from 0.9 to >3% Ro depending on depth of burial for these two cycles. While the Z1 mudrocks deposited above the Rotliegend clastic section are more argillaceous and clay-rich grading upward from calcareous mudstones to intraclast, coated grain, thrombolitic wacke- and packstones into coated-grain grainstones, the Z2 mudrocks are dominated by calcareous to dolomitic laminated mudstones. Both cycles are characterized by microbially bound carbonates ranging from thrombolytic to crenulated laminated structures that are overlain by anhydrite and salt. Stacking patterns of the Z1 3rd-order cycle reveal three 5th-order parasequences stacking into two 4th-order sequences; Z2 3rd-order cycle is composed of three 4th-order parasequences that first deepen and then shallow upwards. Sediments associated

  14. Synthesis and characterization of hydroxyapatite porous matrixes for application as radiation sources in brachytherapy

    International Nuclear Information System (INIS)

    Porous ceramic materials based on calcium phosphate compounds (CPC) have been studied aiming at different biomedical applications such as implants, drug delivery systems and radioactive sources for brachytherapy. Two kinds of hydroxyapatite (HAp) powders and their ceramic bodies were characterized by a combination of different techniques (X-rays diffraction and fluorescence, infrared spectrophotometry, BET method, thermal analysis, and scanning electron microscopy) to evaluate their physico-chemical and microstructural characteristics in terms of chemical composition, segregated phases, microstructure, porosity, and chemical and thermal stability. The results revealed that these systems presented potential for use as porous biodegradable radioactive sources able to be loaded with a wide range of radionuclides for cancer treatment by the brachytherapy technique. (author)

  15. Characterization of laser-produced fast electron source for integrated simulation of fast ignition

    OpenAIRE

    Debayle, Arnaud Philippe Henri; Honrubia Checa, José Javier; d’Humières, E.; Tikhonchuk, V.

    2010-01-01

    Relativistic electron currents (∼ 10 kA µm−2) are produced by focusing an intense laser beam (I ≥ 1019W cm−2) on a solid target. Based on this mechanism, an original inertial confinement fusion scheme has been proposed which consists in heating the compressed deuterium-tritium core with a laser-produced electron beam. Experimentally the fast electron source is not well characterized and simulations of both electron generation and transport remain a difficult task. Generally, transport codes are...

  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 teams efforts characterize the Laboratory’s responsiveness, flexibility, and ability to apply diverse expertise where needed to perform successful complex experiments.

  17. 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.

  18. 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)

  19. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, C.M.; Moniz, P.F.; Reimus, M.A.H.

    1998-12-31

    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 {sup 238}Pu 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.

  1. Characterization and source apportionment of volatile organic compounds in urban and suburban Tianjin, China

    Science.gov (United States)

    Han, Meng; Lu, Xueqiang; Zhao, Chunsheng; Ran, Liang; Han, Suqin

    2015-03-01

    Tianjin is the third largest megacity and the fastest growth area in China, and consequently faces the problems of surface ozone and haze episodes. This study measures and characterizes volatile organic compounds (VOCs), which are ozone precursors, to identify their possible sources and evaluate their contribution to ozone formation in urban and suburban Tianjin, China during the HaChi (Haze in China) summer campaign in 2009. A total of 107 species of ambient VOCs were detected, and the average concentrations of VOCs at urban and suburban sites were 92 and 174 ppbv, respectively. Of those, 51 species of VOCs were extracted to analyze the possible VOC sources using positive matrix factorization. The identified sources of VOCs were significantly related to vehicular activities, which specifically contributed 60% to urban and 42% to suburban VOCs loadings in Tianjin. Industrial emission was the second most prominent source of ambient VOCs in both urban and suburban areas, although the contribution of industry in the suburban area (36%) was much higher than that at the urban area (16%). We conclude that controlling vehicle emissions should be a top priority for VOC reduction, and that fast industrialization and urbanization causes air pollution to be more complex due to the combined emission of VOCs from industry and daily life, especially in suburban areas.

  2. Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry

    Directory of Open Access Journals (Sweden)

    K. R. Daellenbach

    2015-08-01

    Full Text Available Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make impractical its deployment at sufficient sites to determine regional characteristics. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the characterization of their chemical nature and contributing sources. In this study, we utilize the AMS to characterize the water-soluble organic fingerprint of ambient particles collected onto conventional quartz filters, which are routinely sampled at many air quality sites. The method was applied to 256 particulate matter (PM filter samples (PM1, PM2.5, PM10 collected at 16 urban and rural sites during summer and winter. We show that the results obtained by the present technique compare well with those from co-located online measurements, e.g. AMS or Aerosol Chemical Speciation Monitor (ACSM. The bulk recoveries of organic aerosol (60–91 % achieved using this technique, together with low detection limits (0.8 μg of organic aerosol on the analyzed filter fraction allow its application to environmental samples. We will discuss the recovery variability of individual hydrocarbon, oxygen containing and other ions. The performance of such data in source apportionment is assessed in comparison to ACSM data. Recoveries of organic components related to different sources as traffic, wood burning and secondary organic aerosol are presented. This technique, while subjected to the limitations inherent to filter-based measurements (e.g. filter artifacts and limited time resolution may be used to enhance the AMS capabilities in measuring size-fractionated, spatially-resolved long-term datasets.

  3. Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry

    Science.gov (United States)

    Daellenbach, K. R.; Bozzetti, C.; Křepelová, A.; Canonaco, F.; Wolf, R.; Zotter, P.; Fermo, P.; Crippa, M.; Slowik, J. G.; Sosedova, Y.; Zhang, Y.; Huang, R.-J.; Poulain, L.; Szidat, S.; Baltensperger, U.; El Haddad, I.; Prévôt, A. S. H.

    2016-01-01

    Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS) have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make its deployment at sufficient sites to determine regional characteristics impractical. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the characterization of their chemical nature and contributing sources. In this study, we utilize the AMS to characterize the water-soluble organic fingerprint of ambient particles collected onto conventional quartz filters, which are routinely sampled at many air quality sites. The method was applied to 256 particulate matter (PM) filter samples (PM1, PM2.5, and PM10, i.e., PM with aerodynamic diameters smaller than 1, 2.5, and 10 µm, respectively), collected at 16 urban and rural sites during summer and winter. We show that the results obtained by the present technique compare well with those from co-located online measurements, e.g., AMS or Aerosol Chemical Speciation Monitor (ACSM). The bulk recoveries of organic aerosol (60-91 %) achieved using this technique, together with low detection limits (0.8 µg of organic aerosol on the analyzed filter fraction) allow its application to environmental samples. We will discuss the recovery variability of individual hydrocarbon ions, ions containing oxygen, and other ions. The performance of such data in source apportionment is assessed in comparison to ACSM data. Recoveries of organic components related to different sources as traffic, wood burning, and secondary organic aerosol are presented. This technique, while subjected to the limitations inherent to filter-based measurements (e.g., filter artifacts and limited time resolution) may be used to enhance the AMS capabilities in measuring size-fractionated, spatially resolved long-term data sets.

  4. 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

  5. Characterization of dissolved organic matter in drinking water sources impacted by multiple tributaries.

    Science.gov (United States)

    Rosario-Ortiz, Fernando L; Snyder, Shane A; Suffet, I H

    2007-10-01

    The characterization of dissolved organic matter (DOM) in drinking water sources is important as this material contributes to the formation of disinfection by-products (DBPs) and affects how water treatment unit operations are optimized. Drinking water utilities often draw water from sources impacted by multiple tributaries, with possible shifts in DOM concentrations and reactivity over time, depending on specific environmental conditions. In this study, results are presented on the characterization of DOM under varying ambient conditions from the four main tributaries of Lake Mead, a large reservoir in the southwest United States. The tributaries include the Las Vegas Wash (LVW), Muddy River (MR), Virgin River (VR) and the upper Colorado River (UCR). One additional sample was collected at the outflow of the reservoir (lower Colorado River (LCR)). The DOM was characterized by both bulk parameters (specific ultraviolet absorbance (SUVA)) and specific physicochemical properties, i.e. size, polarity and fluorescence. The analyses were performed emphasizing limited changes in its natural configuration by eliminating analytical preparation steps, excluding sample filtration (0.45 microm filter). Results indicate that each tributary had a different molecular weight distribution, as well as fluorescence properties, which helped in the identification of the relative source of DOM (allochthonous versus autochthonous). The largest apparent molecular weight distribution was observed for DOM samples collected at the MR site, which is fed mostly by groundwater seepage. The smallest apparent molecular weight was observed for DOM collected at the LCR site, suggesting that retention in the reservoir resulted in a decrease in molecular weight as a probable result of photo oxidation and microbial processes. Fluorescence analysis aided the differentiation of DOM by clearly identifying waters that were affected by microbial activity (LVW, UCR, and LCR), either by wastewater influence

  6. 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.

  7. Source Characterization of the 15 November 1994, Ms 7.1 Mindoro, Philippines Earthquake

    Science.gov (United States)

    Simplina-Manahan, J. J.

    2004-12-01

    The 14 November 1994, Mindoro, Philippines earthquake (Ms = 7.1) was a major right lateral strike slip event associated to the movement along zones of weakness transecting the Philippine archipelago along the Aglubang River Fault. We examined this event in order to characterize its tectonic origin using the inversion of teleseismic body waveform data and the method developed by Kikuchi and Kanamori (1990). The earthquake was particularly devastating, generating tsunami that has killed 78 persons, and considered as one of the major events since 1992 around the Pacific Rim. The origin of the tsunami has remained an enigma to date in the scientific community. The digitally recorded broadband teleseismic data was downloaded from the archives of IRIS-DMC and was deconvolved to check the direction of P wave initial motion. Retrieved polarity data was then utilized for the estimation of the fault plane solution using the program FOCMEC_@(Snoke). The result suggests an almost purely strike slip faulting in the NE-SW trending direction which correlates well with the mapped trace of ground rupture. The observed waveforms were complicated and show some aspect of multiple shocks. The focal mechanism solutions from the preliminary inversion of teleseismic body waveforms reveal that the event was dominated by major shear faulting, however, the dislocation source based on the parent earthquake failed to model exceptional run-up amplitude. We performed a careful inspection of the body waveforms for multiple event analysis in search for its spatio-temporal distribution. The result suggests that the 1994 Mindoro earthquake consists of two sub-events and that these events are separated by 9 seconds and are located about 30 km apart from each other. We also infer from the inspection that some later pulses observed in the waveforms could be related to depth phase rather than complexity of the source. Effect of wave propagation in the source region was tested by searching the existence

  8. 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.

  9. Development and characterization of a laser-based hard x-ray source

    International Nuclear Information System (INIS)

    A laser-produced plasma was generated by focusing 100 fs laser pulses, with an energy of 150 mJ, onto metal targets. The laser intensity was expected to reach 1017 W/cm-2. Radiation was emitted from the created plasma, with photon energies up to the MeV region. The laser-based X-ray source was optimized, with the purpose of making it a realistic source of hard X-rays (>10 keV). Dedicated equipment was developed for efficient generation and utilization of the hard X-rays. The X-ray source was characterized with respect to its spatial extent and the X-ray yield. Measurements were made of the spectral distribution, by the use of single-photon-counting detectors in different geometries, crystal spectrometers and dose measurements in combination with absorption filters. Ablation of the target material in the laser produced plasma was investigated. Imaging applications have been demonstrated, including ultrafast (picosecond) X-ray imaging, magnification imaging of up to x80, differential imaging in the spectral domain, and imaging of various biological and technical objects. The biological response of ultra-intense X-ray pulses was assessed in cell-culture exposures. The results indicate that the biological response from ultra-intense X-ray exposures is similar to the response with conventional X-ray tubes. 82 refs., 14 figs

  10. Size-resolved trace metal characterization of aerosols emitted by four important source types in Switzerland

    Science.gov (United States)

    Buerki, Peter R.; Gaelli, Brigitte C.; Nyffeler, Urs P.

    In central Switzerland five types of emission sources are mainly responsible for airborne trace metals: traffic, industrial plants burning heavy oil, resuspension of soil particles, residential heatings and refuse incineration plants. The particulate emissions of each of these source types except refuse incineration were sampled using Berner impactors and the mass and elemental size distributions of Cd, Cu, Mn, Pb, Zn, As and Na determined. Cd, Na and Zn are not characteristic for any of these source types. As and Cu, occurring in the fine particle fractions are characteristic for heavy oil combustion, Mn for soil dust and sometimes for heavy and fuel oil combustion and Pb for traffic aerosols. The mass size distributions of aerosols originating from erosion and abrasion processes show a maximum mass fraction in the coarse particle range larger than about 1 μm aerodynamic equivalent diameters (A.E.D.). Aerosols originating from combustion processes show a second maximum mass fraction in the fine particle range below about 0.5μm A.E.D. Scanning electron microscopy combined with an EDS analyzer was used for the morphological characterization of emission and ambient aerosols.

  11. 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.

  12. 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.

  13. 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)

  14. Characterization of a novel x-ray source: The MIRRORCLE-6X system

    International Nuclear Information System (INIS)

    MIRRORCLE is a tabletop synchrotron light source being investigated within an EC funded project named LABSYNC. To evaluate the potential of this novel x-ray source for medical imaging applications, a set of measurements was performed at the MIRRORCLE factory in Japan. In particular, the aim of this work was to characterize the proposed compact x-ray source by determining different parameters, such as the intensity of the broad spectra produced with thin wire targets, the size of the focal spot and its distribution. The average electron-beam impact current on wire targets was calculated by several methods and it was demonstrated to be in the range 0.5-1.0μA. By comparing these values with data available for conventional x-ray tubes, the current needed to achieve the same fluence as in a standard diagnostic examination was estimated to be about 0.1-0.5 mA. Finally, results from the measurements of the electron-beam impact cross-section on the target suggested that the diameter of the electron beam circulating in the storage ring is about 6 mm.

  15. 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.

  16. 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.

  17. 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.

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

    International Nuclear Information System (INIS)

    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 PM10 levels. A total of 94 PM samples were collected in two sampling campaigns that occurred in February and June/July of 2011. PM2.5 and PM2.5–10 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 PM10 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 PM10. 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 NH4+, 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 PM10 was from blast furnace and sinter plant. • Sinter plant stack emissions contributed for 12% of the PM10 mass. • Secondary aerosol from coke making and blast furnace contributed for 19% of the PM10. • Fugitive dust emissions highly contribute to PM10 mass

  19. 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

  20. Sources

    International Nuclear Information System (INIS)

    This paper discusses the sources of radiation in the narrow perspective of radioactivity and the even narrow perspective of those sources that concern environmental management and restoration activities at DOE facilities, as well as a few related sources. Sources of irritation, Sources of inflammatory jingoism, and Sources of information. First, the sources of irritation fall into three categories: No reliable scientific ombudsman to speak without bias and prejudice for the public good, Technical jargon with unclear definitions exists within the radioactive nomenclature, and Scientific community keeps a low-profile with regard to public information. The next area of personal concern are the sources of inflammation. This include such things as: Plutonium being described as the most dangerous substance known to man, The amount of plutonium required to make a bomb, Talk of transuranic waste containing plutonium and its health affects, TMI-2 and Chernobyl being described as Siamese twins, Inadequate information on low-level disposal sites and current regulatory requirements under 10 CFR 61, Enhanced engineered waste disposal not being presented to the public accurately. Numerous sources of disinformation regarding low level radiation high-level radiation, Elusive nature of the scientific community, The Federal and State Health Agencies resources to address comparative risk, and Regulatory agencies speaking out without the support of the scientific community

  1. 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

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

    International Nuclear Information System (INIS)

    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

  3. 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

  4. 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%.

  5. 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%.

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

    International Nuclear Information System (INIS)

    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%.

  7. 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)

  8. 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)

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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)

  14. 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.

  15. Source Term Characterization of HANARO spent fuel for disposal system design

    International Nuclear Information System (INIS)

    Source term characterization for domestic spent fuels has been carried out in a project, 'Development of a Korean Reference disposal System(A-KRS) for the HLW from Advanced Fuel cycles', to propose a high level waste repository accommodating all domestic spent fuels. The domestic spent fuels includes PWR spent fuels, PHWR spent fuels, and HANARO(research reactor) spent fuels. The key input parameters for spent nuclear fuels are total inventory, radioactivity, and decay heat. In this report, a inventory of spent fuels to be generated during entire life-time of HANARO reactor was estimated. Radioactivity and decay heat from HANARO spent fuels were also evaluated by using ORIGEN-ARP. It was expected that about 2 tons of spent fuels would be generated by the time of saturation of storage pool. In case that a capacity of storage pool is extended, about 3 tons of spent fuels were expected. It also revealed that the decay heat of HANARO spent fuel is higher than that of PWR or CANDU spent fuels. It is expected that the source terms calculated in this report would be very useful in the design of disposal system accommodating the HANARO spent fuel

  16. HELIOS-R: An Ultrafast, Open-Source Retrieval Code For Exoplanetary Atmosphere Characterization

    Science.gov (United States)

    LAVIE, Baptiste

    2015-12-01

    Atmospheric retrieval is a growing, new approach in the theory of exoplanet atmosphere characterization. Unlike self-consistent modeling it allows us to fully explore the parameter space, as well as the degeneracies between the parameters using a Bayesian framework. We present HELIOS-R, a very fast retrieving code written in Python and optimized for GPU computation. Once it is ready, HELIOS-R will be the first open-source atmospheric retrieval code accessible to the exoplanet community. As the new generation of direct imaging instruments (SPHERE, GPI) have started to gather data, the first version of HELIOS-R focuses on emission spectra. We use a 1D two-stream forward model for computing fluxes and couple it to an analytical temperature-pressure profile that is constructed to be in radiative equilibrium. We use our ultra-fast opacity calculator HELIOS-K (also open-source) to compute the opacities of CO2, H2O, CO and CH4 from the HITEMP database. We test both opacity sampling (which is typically used by other workers) and the method of k-distributions. Using this setup, we compute a grid of synthetic spectra and temperature-pressure profiles, which is then explored using a nested sampling algorithm. By focusing on model selection (Occam’s razor) through the explicit computation of the Bayesian evidence, nested sampling allows us to deal with current sparse data as well as upcoming high-resolution observations. Once the best model is selected, HELIOS-R provides posterior distributions of the parameters. As a test for our code we studied HR8799 system and compared our results with the previous analysis of Lee, Heng & Irwin (2013), which used the proprietary NEMESIS retrieval code. HELIOS-R and HELIOS-K are part of the set of open-source community codes we named the Exoclimes Simulation Platform (www.exoclime.org).

  17. Development of a High Fluence Neutron Source for Nondestructive Characterization of Nuclear Waste

    International Nuclear Information System (INIS)

    We are addressing the need to measure nuclear wastes, residues, and spent fuel in order to process these for final disposition. For example, TRU wastes destined for the WIPP must satisfy extensive characterization criteria outlined in the Waste Acceptance Criteria, the Quality Assurance Program Plan, and the Performance Demonstration Plan. Similar requirements exist for spent fuel and residues. At present, no nondestructive assay (NDA) instrumentation is capable of satisfying all of the PDP test cycles (particularly for Remote-Handled TRU waste). One of the primary methods for waste assay is by active neutron interrogation. The objective of this project is to improve the capability of all active neutron systems by providing a higher intensity neutron source (by about a factor of 1,000) for essentially the same cost, power, and space requirements as existing systems. This high intensity neutron source is an electrostatically confined (IEC) plasma device. The IEC is a symmetric sphere that was originally developed in the 1960s as a possible fusion reactor. It operates as DT neutron generator. Although it is not likely that this device will scale to fusion reactor levels, previous experiments1 have demonstrated a neutron yield of 2 x 1010 neutrons/second on a table-top device that can be powered from ordinary laboratory circuits (9 kilowatts). Subsequently, the IEC physics has been extensively studied at the University of Illinois and other locations. We have established theoretically the basis for scaling the output up to 1 x 1011 neutrons/second. In addition, IEC devices have run for cumulative times approaching 10,000 hours, which is essential for practical application to NDA. They have been operated in pulsed and continuous mode. The essential features of the IEC plasma neutron source, compared to existing sources of the same cost, size and power consumption, are: Table 1: Present and Target Operating Parameters for Small Neutron Generators Parameter Present IEC

  18. Characterization, sources and redox activity of fine and coarse particulate matter in Milan, Italy

    Science.gov (United States)

    Daher, Nancy; Ruprecht, Ario; Invernizzi, Giovanni; De Marco, Cinzia; Miller-Schulze, Justin; Heo, Jong Bae; Shafer, Martin M.; Shelton, Brandon R.; Schauer, James J.; Sioutas, Constantinos

    2012-03-01

    The correlation between health effects and exposure to particulate matter (PM) has been of primary concern to public health organizations. An emerging hypothesis is that many of the biological effects derive from the ability of PM to generate reactive oxygen species (ROS) within affected cells. Milan, one of the largest and most polluted urban areas in Europe, is afflicted with high particle levels. To characterize its ambient PM, fine and coarse PM (PM2.5 and PM2.5-10, respectively) samples were collected on a weekly basis for a year-long period. Samples were analyzed for their chemical properties and ROS-activity. A molecular marker chemical mass balance (MM-CMB) model was also applied to apportion primary and secondary sources to fine organic carbon (OC) and PM. Findings revealed that PM2.5 is a major contributor to ambient particle levels in Milan, averaging 34.5 ± 19.4 μg m-3 throughout the year. Specifically, secondary inorganic ions and organic matter were the most dominant fine PM species contributing to 36 ± 7.1% and 34 ± 6.3% of its mass on a yearly-based average, respectively. Highest PM2.5 concentrations occurred during December-February and were mainly attributed to poor atmospheric dispersion. On the other hand, PM2.5-10 exhibited an annual average of 6.79 ± 1.67 μg m-3, with crustal elements prevailing. Source apportionment results showed that wood-smoke and secondary organic aerosol sources contribute to 4.6 ± 2.6% and 9.8 ± 11% of fine OC on a yearly-based average, respectively. The remaining OC is likely associated with petroleum-derived material that is not adequately represented by existing source profiles used in this study. Lastly, ROS-activity measurements indicated that PM2.5-induced redox activity expressed per m3 of air volume is greatest during January (837 μg Zymosan equivalents m-3) and February (920 μg Zymosan equivalents m-3). Conversely, intrinsic (per PM mass) ROS-activity peaked in July (22,587 μg Zymosan equivalents mg

  19. 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)

  20. 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....

  1. 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

  2. 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

  3. Growth and Characterization of Hydrogenated Amorphous Silicon and Hydrogenated Amorphous Silicon Carbide with Liquid Organometallic Sources.

    Science.gov (United States)

    Gaughan, Kevin David

    The growth and characterization of hydrogenated amorphous silicon (a-Si:H) and hydrogenated amorphous silicon -carbon (rm a-rm Si _{1-X}C_{X}: H) alloys employing liquid organometallic sources are described. N -type a-Si:H films were grown using a mixture of silane and tertiarybutylphosphine (TBP-rm C_4H _9P_2) vapor in a plasma enhanced chemical vapor deposition system. Impurity levels from parts per million to about 5 at. % phosphorus have been incorporated into the film with this method. Tertiarybutylphosphine is less toxic and less pyrophoric than phosphine which is usually used in n-type doping of a-Si:H films. Optical and electronic properties were characterized by room temperature as well as temperature dependent dark conductivity, photothermal deflection spectroscopy, infrared vibrational spectroscopy, electron spin resonance, and electron microprobe analysis. The gross doping properties of a-Si:H doped with TBP are the same as those obtained with phosphine. The experimental results are compared with the predictions of several models that describe the chemical equilibrium between active dopants and deep defects. A pronounced decrease in the effects of doping, such as an increase in the activation energy of electrical conductivity and an decrease in the conductivity of the sample, were seen in heavily doped films (TBP/SiH _4> 0.5%), perhaps influenced by the increased carbon and/or phosphorus concentrations. Amorphous silicon-carbide alloys have been grown by the plasma decomposition of ditertiarybutylsilane ( rm DTBS-rm SiH_2(C _4H_9)_2). The optical bandgaps, which varied from 2.2 to 3.3 eV, are strongly dependent upon the deposition conditions. The carbon concentrations in these films varied from 60 to 95 at. %. The optical band-edge is very broad compared to that which is found in a-Si:H and this breadth is essentially independent of the deposition conditions. The plasma decomposition of admixtures of DTBS and silane has produced rm a- rm Si_{1-X

  4. 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

  5. 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

  6. Isolation and Characterization of Bacteria That Use Furans as the Sole Carbon Source.

    Science.gov (United States)

    Lee, Sarah A; Wrona, Lindsey J; Cahoon, A Bruce; Crigler, Jacob; Eiteman, Mark A; Altman, Elliot

    2016-01-01

    Five bacterial strains were isolated from wastewater treatment facilities which were able to use furfural as the sole carbon source. Based on 16S rRNA phylogenetic analysis, these strains were identified as Cupriavidus pinatubonensis (designated ALS1280), Pigmentiphaga sp. (ALS1172), Pseudomonas sp. BWDY (ALS1279), Pseudomonas mendocina (ALS1131), and Pseudomonas putida (ALS1267). In all cases, growth under oxygenated conditions on furfural was accompanied by the transient accumulation of 2-furoic acid (furoate) with no furfuryl alcohol observed. ALS1267 and ALS1279 were also able to metabolize 5-(hydroxymethyl)furfural. The five isolates and their phylogenetic near neighbors were compared for furfural dehydrogenase activity and tolerance to furfural and furoate in defined and complex media. P. putida ALS1267 was the most tolerant to furans and tolerated 17 mM furfural or 195 mM furoate before its growth rate was reduced by 50 % in a defined medium. This strain also had the greatest specific growth rate on furfural (0.6/h at 27-30 °C) and showed the highest specific activity of furfural dehydrogenase (170 mIU/mg) of any furfural-utilizing strain that has been characterized to date. PMID:26419660

  7. Initial source and site characterization studies for the U.C. Santa Barbara campus

    Energy Technology Data Exchange (ETDEWEB)

    Archuleta, R.; Nicholson, C.; Steidl, J.; Gurrola, L.; Alex, C.; Cochran, E.; Ely, G.; Tyler, T. [University of California, Santa Barbara (United States)

    1997-12-01

    The University of California Campus-Laboratory Collaboration (CLC) project is an integrated 3 year effort involving Lawrence Livermore National Laboratory (LLNL) and four UC campuses - Los Angeles (UCLA), Riverside (UCR), Santa Barbara (UCSB), and San Diego (UCSD) - plus additional collaborators at San Diego State University (SDSU), at Los Alamos National Laboratory and in industry. The primary purpose of the project is to estimate potential ground motions from large earthquakes and to predict site-specific ground motions for one critical structure on each campus. This project thus combines the disciplines of geology, seismology, geodesy, soil dynamics, and earthquake engineering into a fully integrated approach. Once completed, the CLC project will provide a template to evaluate other buildings at each of the four UC campuses, as well as provide a methodology for evaluating seismic hazards at other critical sites in California, including other UC locations at risk from large earthquakes. Another important objective of the CLC project is the education of students and other professional in the application of this integrated, multidisciplinary, state-of-the-art approach to the assessment of earthquake hazard. For each campus targeted by the CLC project, the seismic hazard study will consist of four phases: Phase I - Initial source and site characterization, Phase II - Drilling, logging, seismic monitoring, and laboratory dynamic soil testing, Phase III - Modeling of predicted site-specific earthquake ground motions, and Phase IV - Calculations of 3D building response. This report cover Phase I for the UCSB campus and incudes results up through March 1997.

  8. Mantle source characterization of Sylhet traps, northeastern India: a petrological and geochemical study

    International Nuclear Information System (INIS)

    In this study, mineralogical, geochemical, and isotopic data are presented for the Sylhet Trap at the southern flank of the eastern Shillong Plateau, northeastern India, to determine the magma genesis in relation to the Kerguelen plume mantle source. Sylhet Trap rocks are porphyritic tholeiite and have diverse chemical compositions from picro-basalt, basalt, andesite to dacite, but mostly are within the subalkaline field. Major and trace element data were used to identify two distinct magma fractionation trends, a low and medium K series, characterized by relatively flat MORB-like (analogous to Rajmahal Traps (II)) and enriched OIB chondrite-normalized Rare Earth Element (REE) patterns. Initial 87Sr/86Sr, 143Nd/144Nd, and 206Pb/204Pb isotope compositions were widely varied, ranging from 0.70435-0.71357, 0.51196-0.51266, and 17.92-19.72, respectively, when compared with basalts from the West Bengal, the Rajmahal Traps and the Kerguelen plume. Correlations among isotopic and trace element ratios of the Sylhet Traps provide evidence for the involvement of (1) HIMU-like mantle component (2) the Kerguelen plume-like component, and (3) EMII-like crustal component. Magma from the Sylhet Traps was originated from a melting that derived directly from the heterogeneous Kerguelen mantle plume (components 1 and 2), which strongly suggests the presence of the Kerguelen plume-head in the Bengal basin. (author)

  9. 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)

  10. 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.

  11. 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)

  12. 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

  13. Sources

    OpenAIRE

    2011-01-01

    A. SOURCES STATISTIQUES 1. Statistiques générales Annuaire statistique international, SDN (à partir de 1926). Mémorandum sur le commerce international et sur les balances des paiements, annuel à partir de 1927 (numéros rétrospectifs 1912-1926, 1913-1927), [3 volumes : aperçu général ; balances des paiements ; statistiques du commerce extérieur ; utilise les données nationales disponibles. Très utile]. Annuaire statistique de la France. Annuaire statistique de la Belgique. Statistiques économi...

  14. Sources

    OpenAIRE

    2013-01-01

    I–SOURCES MANUSCRITES Archivio di Stato di Roma (ASR) Presidenza dell’Annona e Grascia : bb. 67-68, Lista dei misuratori del grano, 1658-1660. bb. 352-377, Nota dei grani introdotti e venduti in Roma, 1657-1715. bb. 412-419, Ristretto delle assegne dei grani date dai mercanti, 1680-1687. b. 1470, Registro delle lettere del Prefetto dell’Annona, 1659-1660. b. 1706, Libri di entrata e uscita dei grani dell’abbondanza (Ripetta), 16581670. bb. 1930-1931, Debiti e crediti dei fornai, 1658-1660. b....

  15. Sources

    OpenAIRE

    2014-01-01

    Sources éditées : ABADAL i de VINYALS, Ramon d', Catalunya carolingia, II, Els diplomes carolingis a Catalunya, 2 vol., Barcelone, 1926-1952, cit. CC. ACHERY, D', Luc, Spicilegium sive collectio veterum aliquot scriptorum..., E. Baluze et E. Martène éd., Paris, 1723, tome 3. ALART, Bernard, Privilèges et titres relatifs aux franchises, institutions et propriétés communales de Roussillon et de Cerdagne depuis le xie siècle jusqu 'à l'an 1660... Première partie, Perpignan, 1878. ALART, Bernard,...

  16. Rapid and robust characterization of the earthquake source for tsunami early-warning

    Science.gov (United States)

    Lomax, Anthony; Michelini, Alberto; Bernardi, Fabrizio; Lauciani, Valentino

    2015-04-01

    Effective tsunami early-warning after an earthquake is difficult when the distances and tsunami travel-times between earthquake/tsunami source regions and coast lines at risk are small, especially since the density of seismic and other monitoring stations is very low in most regions of risk. For tsunami warning worldwide, seismic monitoring and analysis currently provide the majority of information available within the first tens of minutes after an earthquake. This information is used for direct tsunami hazard assessment, and as basic input to real-time, tsunami hazard modeling. It is thus crucial that key earthquake parameters are determined as rapidly and reliably as possible, in a probabilistic, time-evolving manner, along with full uncertainties. Early-est (EArthquake Rapid Location sYstem with EStimation of Tsunamigenesis) is the module for rapid earthquake detection, location and analysis at the INGV tsunami alert center (CAT, "Centro di Allerta Tsunami"), part of the Italian, candidate Tsunami Watch Provider. Here we present the information produced by Early-est within the first 10 min after an earthquake to characterize the location, depth, magnitude, mechanism and tsunami potential of an earthquake. We discuss key algorithms in Early-est that produce fully automatic, robust results and their uncertainties in the shortest possible time using sparse observations. For example, a broadband picker and a robust, probabilistic, global-search detector/associator/locator component of Early-est can detect and locate a seismic event with as few as 4 to 5 P onset observations. We also discuss how these algorithms may be further evolved to provide even earlier and more robust results. Finally, we illustrate how the real-time, evolutionary and probabilistic earthquake information produced by Early-est, along with prior and non-seismic information and later seismic information (e.g., full-waveform moment-tensors), may be used within time-evolving, decision and modeling

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Lead isotopic characterization of respirable urban aerosols and related sources, Santiago-Chile

    International Nuclear Information System (INIS)

    Santiago de Chile is located in a poorly ventilated valley at 33o30' latitude south at an altitude of 550m. Local climate is semi-arid with mean annual rainfall below 350mm. The atmospheric particles constitute one of the main factors of urban air pollution in the city. Morphological characterization of airborne particles of Santiago done by Scanning Electron Microscopy showed the presence of three groups of particles: crystalline. spherical and agglomerate particles. The crystalline shapes originated in geologic sources have perfectly defined crystallographic parameters. The agglomerated shapes are formed by organic material and submicrometrical mineral particles derived from combustion of fossil fuel and the spherical shapes are products of metallurgical activities. Some of them could been associated with the wear of motorcars. Samples of aerosols. sediments and leaded petrol of different distributors were collected. Aerosols were sampled in two sites of Santiago: the Movil monitoring station, at east of the city, and Parque O'Higgins monitoring station in downtown. These two monitoring stations belong to the MACAM network. Sediments of Mapocho, Maipo, San Francisco and Zanjon de la Aguada rivers and two samples from Disputada and Merceditas ores were studied. All the samples have been measured for their 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios. The experimental chemical procedures of sample dissolution and Pb separation by anion exchange chromatography were developed in the Sernageomin clean laboratory of Santiago de Chile. The isotopic measurements were made using a VG-Sector isotope ratio mass spectrometer fitted with a thermal ion source, multi Faraday collector and Daly collector of the Isotopic Geology Laboratory in the Universidade Federal de Rio Grande do Sul, Brazil. The measurements were corrected using NBS 981 and 982 standards. Isotopic results plotted in a 208Pb/204Pb versus 206Pb/204Pb diagram and in a 207Pb/204Pb versus 206Pb/204Pb diagram

  2. 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.

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

    Science.gov (United States)

    Sudhir, Dass; Bandyopadhyay, M.; Chakraborty, A.

    2016-02-01

    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.

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

    International Nuclear Information System (INIS)

    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

  5. Rapid detection and characterization of large earthquakes using quasi-finite-source Green's functions in continuous moment tensor inversion

    Science.gov (United States)

    Guilhem, Aurélie; Dreger, Douglas S.

    2011-07-01

    Large earthquakes along subduction zones have the potential to generate tsunamis along local coasts, as well as traveling far across oceans. By continuously inverting for moment tensors we show that it is possible with a single procedure to automatically detect, locate and determine source parameters of any earthquake, from magnitude 3.5 to larger than 8 located in both the near- and far-field. We find that the detection and characterization of large earthquakes is improved when quasi-finite-source Green's functions are used in a point-source moment tensor approach as they represent to some extent the rupture's finiteness and directivity. Solutions can be obtained within several minutes after the origin time of the earthquake, and could therefore be used as part of a near-source tsunami early warning system, capable of providing tens of minutes of possible warning depending on the distance of the earthquake rupture from the coast.

  6. 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

  7. 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.

  8. Characterization of large-area reference sources for the calibration of beta-contamination monitors

    Science.gov (United States)

    Janßen, H.; Klein, R.

    1996-02-01

    A method has been developed whereby the activity of a large-area reference source for the calibration of beta-contamination monitors can be determined from a series of measured countrates in a suitable detection system as a function of the distance between the surface of the source and the front face of the detector.

  9. An analytical method applied to transport inverse problems characterized by determination of inside source in the discrete ordinates formulation

    International Nuclear Information System (INIS)

    It is described an analytical discrete ordinates (SN) transport method for the inverse problem characterized by the determination of the intensity of an isotropic, monoenergetic and uniform neutron source stored inside a container. Our model is based on the one-speed-slab-geometry SN formulation with linearly anisotropic scattering, and we have used the Spectral Green's Function Method, which generates numerical results that are completely free from all spatial truncation errors. (author). 2 refs, 1 fig, 5 tabs

  10. 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...

  11. 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.

  12. 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.

  13. 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...

  14. Source characterization using compound composition and stable carbon isotope ratio of PAHs in sediments from lakes, harbor, and shipping waterway

    International Nuclear Information System (INIS)

    Molecular compositions and compound specific stable carbon isotope ratios of polycyclic aromatic hydrocarbons (PAH) isolated from sediments were used to characterize possible sources of contamination at an urban lake, a harbor, a shipping waterway, and a relatively undisturbed remote lake in the northwest United States. Total PAH concentrations in urban lake sediments ranged from 66.0 to 16,500 μg g-1 dry wt. with an average of 2600 μg g-1, which is ∼ 50, 100, and 400 times higher on average than PAH in harbor (48 μg g-1 on average), shipping waterway (26 μg g-1), and remote lake (7 μg g-1) sediments, respectively. The PAH distribution patterns, methyl phenanthrene/phenanthrene ratios, and a pyrogenic index at the sites suggest a pyrogenic origin for PAHs. Source characterization using principal component analysis and various molecular indices including C2-dibenzothiophenes/C2-phenanthrenes, C3-dibenzothiophenes/C3-phenanthrenes, and C2-chrysenes/C2-phenanthrenes ratios, was able to differentiate PAH deposited in sediments from the four sites. The uniqueness of the source of the sediment PAHs from urban lake was also illustrated by compound specific stable carbon isotope analysis. It was concluded that urban lake sediments are accumulating PAH from sources that are unique from contamination detected at nearby sites in the same watershed

  15. Characterizing the hypersiliceous rocks of Belgium used in (pre-)history: a case study on sourcing sedimentary quartzites

    International Nuclear Information System (INIS)

    Tracking raw material back to its extraction source is a crucial step for archaeologists when trying to deduce migration patterns and trade contacts in (pre-)history. Regarding stone artefacts, the main rock types encountered in the archaeological record of Belgium are hypersiliceous rocks. This is a newly introduced category of rock types comprising those rocks made of at least 90% silica. These are strongly silicified quartz sands or sedimentary quartzites, siliceous rocks of chemical and biochemical origin (e.g. flint), very pure metamorphic quartzites and siliceous volcanic rocks (e.g. obsidian). To be able to distinguish between different extraction sources, ongoing research was started to locate possible extraction sources of hypersiliceous rocks and to characterize rocks collected from these sources. Characterization of these hypersiliceous rocks is executed with the aid of optical polarizing microscopy, optical cold cathodoluminescence and scanning-electron microscopy combined with energy-dispersive x-ray spectrometry and with back-scatter electron imaging. In this paper, we focus on various sedimentary quartzites of Paleogene stratigraphical level. (paper)

  16. The quantitative characterization of free radical sources and traps by electromigration applications.

    Science.gov (United States)

    Donáth-Nagy, Gabriella; Buchwald, Peter; Vancea, Szende; Croitoru, Mircea; Tokés, Béla

    2008-04-24

    Nowadays, very diverse human activities generate urgent demands for fast, sensitive reliable innovative tools capable of detecting major industrial, military, and other dangerous products. An important part of these compounds are free radicals. Capillary electrophoresis (CE), especially in its miniaturized format (lab-on-a-chip), and other electromigration methods offer special possibilities to resolve this problem. These measurements have a great opportuness because of very wide chemical and biological role of free radicals. Several compounds, e.g. monomers and some biologically important groups (as are nitrones) oppose oxidative challenges by virtue of their trap very rapidly oxygen- or carbon-centered radicals and generating other radical species which are stable and biochemically less harmful than the original ones. In many cases, conventionally, the relative trap capacity is measured against tert.-butylhydroperoxide (TBH). In this lecture are presented numerous important free radical species (active oxygen-, nitrogen- and carbon-centered ones, as HO, NO etc) and their adequate in vitro and in vivo applied bioanalytical methods, including liquid chromatography with electrochemical detection and mass spectrometry, gas chromatography with mass spectrometry, capillary electrophoresis, electron spin resonance and chemiluminescence analysis. A simple and highly sensitive method is the capillary zone electrophoresis with amperometric detection (CZE-AD); It was introduced to determine indirectly OH by analysing its reaction products with salicylic and dihydroxybenzoic acids. Hydroxylated radical products of these acids are often used as a relative measurement in free radical research. Accurate determination of pK(a) values is important for proper characterization of newly synthesized molecules. CZE method was used for determination of their values. Are initiated new research fields as Fenton-, electro-Fenton and photoelectro-Fenton chemistry and foreseen their

  17. 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.

  18. Dosimetric characterization of the Cobal-60 bebig Co0.A86 source, using Monte Carlo simulation

    International Nuclear Information System (INIS)

    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)

  19. Characterization and collection of information from heterogeneous multimedia sources with users' parameters for decision support

    CERN Document Server

    Robert, Charles A B

    2008-01-01

    No single information source can be good enough to satisfy the divergent and dynamic needs of users all the time. Integrating information from divergent sources can be a solution to deficiencies in information content. We present how Information from multimedia document can be collected based on associating a generic database to a federated database. Information collected in this way is brought into relevance by integrating the parameters of usage and user's parameter for decision making. We identified seven different classifications of multimedia document.

  20. Comparison of Source Term Analysis Result with Measured Data for Spent Fuel Characterization

    International Nuclear Information System (INIS)

    The source terms of assembly hardware for an intact SF are not an important concern in relation to deep geological disposal, because major activities are contributed by the decay of nuclides in the irradiated fuel itself. However, the source terms of the assembly hardware in the aforementioned advanced fuel cycle become relatively important, because major nuclides contributing to radioactivity and decay heat nuclides contributing to radioactivity and decay heat are removed by the pyro process for recycling and interim storage. It was found that about 90% the PWR assembly hardware should be deposed of at a deep geological repository. A source term evaluation for assembly hardware with a single irradiation profile can be easily accomplished with the conventional computation tool. However, source term assessment for a batch of assembly hardware or a mixture of metal wastes generated from SAS with different irradiation profiles a task that is essential to support the source term generation for the design of a disposal system is impossible with the conventional tool. This shortcoming was overcome through the development of an advanced source term estimation program in our country. However, the developed program has not been sufficiently verified yet. Therefore, the program was verified by comparing the estimated nuclide inventory in irradiated assembly hardware in the present study. The Republic of Korea has developed an advanced source term analysis tool, called ASOURCE, to support R and D action plans for the achievement of an advanced fuel cycle employing a pyro process in connection with a sodium-cooled fast reactor. It was found that the nuclide inventory calculated by ASOURCE for irradiated fuel cladding agreed with the measured data within 35%, indicating that the developed program supplies viable source term data

  1. Characterization of the neutron field from the 241Am-Be isotopic source of the IPHC irradiator

    International Nuclear Information System (INIS)

    A measurement campaign has been carried out recently to provide the source intensity and the reference spectra around a neutron irradiation facility based on 241Am-Be radionuclide source, using the UAB Bonner Sphere Spectrometer. This facility, which consists of a bunker, a container/shielding for the source and an irradiation device that uses an automated remote-controlled system for the source positioning and rotating during the dosimeter irradiation, is intended to be routinely used to check the response of passive dosimeters, namely those based on photo-stimulated imaging plates and solid-state nuclear track detectors. The measurement results, in terms of neutron spectra and global dosimetric quantities (i.e., fluence and ambient dose equivalent rates) at different distances with respect to the 241Am-Be source, were compared with Monte Carlo simulations using the MCNPX code and a good agreement was observed. An estimation of the un-scattered neutron spectrum directly emitted from the 241Am-Be source is given as well. - Highlights: ► We describe a neutron irradiation facility based on 241Am-Be radioactive source. ► The neutron field was characterized with a Bonner sphere spectrometer (BSS). ► Monte Carlo simulations using the MCNPX code were in good agreement with BSS. ► The un-scattered neutron spectrum is provided and compared to that given by the ISO-8529 standard. ► The neutron intensity of the 241Am-Be source is also estimated

  2. Compact quasi-monoenergetic photon sources from laser-plasma accelerators for nuclear detection and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Geddes, Cameron G.R., E-mail: cgrgeddes@lbl.gov; Rykovanov, Sergey; Matlis, Nicholas H.; Steinke, Sven; Vay, Jean-Luc; Esarey, Eric H.; Ludewigt, Bernhard; Nakamura, Kei; Quiter, Brian J.; Schroeder, Carl B.; Toth, Csaba; Leemans, Wim P.

    2015-05-01

    Near-monoenergetic photon sources at MeV energies offer improved sensitivity at greatly reduced dose for active interrogation, and new capabilities in treaty verification, nondestructive assay of spent nuclear fuel and emergency response. Thomson (also referred to as Compton) scattering sources are an established method to produce appropriate photon beams. Applications are however restricted by the size of the required high-energy electron linac, scattering (photon production) system, and shielding for disposal of the high energy electron beam. Laser-plasma accelerators (LPAs) produce GeV electron beams in centimeters, using the plasma wave driven by the radiation pressure of an intense laser. Recent LPA experiments are presented which have greatly improved beam quality and efficiency, rendering them appropriate for compact high-quality photon sources based on Thomson scattering. Designs for MeV photon sources utilizing the unique properties of LPAs are presented. It is shown that control of the scattering laser, including plasma guiding, can increase photon production efficiency. This reduces scattering laser size and/or electron beam current requirements to scale compatible with the LPA. Lastly, the plasma structure can decelerate the electron beam after photon production, reducing the size of shielding required for beam disposal. Together, these techniques provide a path to a compact photon source system.

  3. 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.

  4. Compact quasi-monoenergetic photon sources from laser-plasma accelerators for nuclear detection and characterization

    International Nuclear Information System (INIS)

    Near-monoenergetic photon sources at MeV energies offer improved sensitivity at greatly reduced dose for active interrogation, and new capabilities in treaty verification, nondestructive assay of spent nuclear fuel and emergency response. Thomson (also referred to as Compton) scattering sources are an established method to produce appropriate photon beams. Applications are however restricted by the size of the required high-energy electron linac, scattering (photon production) system, and shielding for disposal of the high energy electron beam. Laser-plasma accelerators (LPAs) produce GeV electron beams in centimeters, using the plasma wave driven by the radiation pressure of an intense laser. Recent LPA experiments are presented which have greatly improved beam quality and efficiency, rendering them appropriate for compact high-quality photon sources based on Thomson scattering. Designs for MeV photon sources utilizing the unique properties of LPAs are presented. It is shown that control of the scattering laser, including plasma guiding, can increase photon production efficiency. This reduces scattering laser size and/or electron beam current requirements to scale compatible with the LPA. Lastly, the plasma structure can decelerate the electron beam after photon production, reducing the size of shielding required for beam disposal. Together, these techniques provide a path to a compact photon source system

  5. 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.

  6. Dosimetry characterization of $^{32}$P intravascular brachytherapy source wires using Monte Carlo codes PENELOPE and GEANT4

    CERN Document Server

    Torres, J; Almansa, J F; Guerrero, R; Lallena, A M; Torres, Javier; Buades, Manuel J.; Almansa, Julio F.; Guerrero, Rafael; Lallena, Antonio M.

    2003-01-01

    Monte Carlo calculations using the codes PENELOPE and GEANT4 have been performed to characterize the dosimetric parameters of the new 20 mm long catheter based $^{32}$P beta source manufactured by Guidant Corporation. The dose distribution along the transverse axis and the two dimensional dose rate table have been calculated. Also, the dose rate at the reference point, the radial dose function and the anisotropy function were evaluated according to the adapted TG-60 formalism for cylindrical sources. PENELOPE and GEANT4 codes were first verified against previous results corresponding to the old 27 mm Guidant $^{32}$P beta source. The dose rate at the reference point for the unsheathed 27 mm source in water was calculated to be $0.215 \\pm 0.001$ cGy s$^{-1}$ mCi$^{-1}$, for PENELOPE, and $0.2312 \\pm 0.0008$ cGy s$^{-1}$ mCi$^{-1}$, for GEANT4. For the unsheathed 20 mm source these values were $0.2908 \\pm 0.0009$ cGy s$^{-1}$ mCi$^{-1}$ and $0.311 \\pm 0.001$ cGy s$^{-1}$ mCi$^{-1}$, respectively. Also, a compar...

  7. 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.

  8. Characterization of emissions from South Asian biofuels and application to source apportionment of carbonaceous aerosol in the Himalayas

    Science.gov (United States)

    Stone, Elizabeth A.; Schauer, James J.; Pradhan, Bidya Banmali; Dangol, Pradeep Man; Habib, Gazala; Venkataraman, Chandra; Ramanathan, V.

    2010-03-01

    This study focuses on improving source apportionment of carbonaceous aerosol in South Asia and consists of three parts: (1) development of novel molecular marker-based profiles for real-world biofuel combustion, (2) application of these profiles to a year-long data set, and (3) evaluation of profiles by an in-depth sensitivity analysis. Emissions profiles for biomass fuels were developed through source testing of a residential stove commonly used in South Asia. Wood fuels were combusted at high and low rates, which corresponded to source profiles high in organic carbon (OC) or high in elemental carbon (EC), respectively. Crop wastes common to the region, including rice straw, mustard stalk, jute stalk, soybean stalk, and animal residue burnings, were also characterized. Biofuel profiles were used in a source apportionment study of OC and EC in Godavari, Nepal. This site is located in the foothills of the Himalayas and was selected for its well-mixed and regionally impacted air masses. At Godavari, daily samples of fine particulate matter (PM2.5) were collected throughout the year of 2006, and the annual trends in particulate mass, OC, and EC followed the occurrence of a regional haze in South Asia. Maximum concentrations occurred during the dry winter season and minimum concentrations occurred during the summer monsoon season. Specific organic compounds unique to aerosol sources, molecular markers, were measured in monthly composite samples. These markers implicated motor vehicles, coal combustion, biomass burning, cow dung burning, vegetative detritus, and secondary organic aerosol as sources of carbonaceous aerosol. A molecular marker-based chemical mass balance (CMB) model provided a quantitative assessment of primary source contributions to carbonaceous aerosol. The new profiles were compared to widely used biomass burning profiles from the literature in a sensitivity analysis. This analysis indicated a high degree of stability in estimates of source

  9. Establishing Global Source-Receptor Relationships for Carbonaceous Aerosol to Characterize Sensitivity of its Climate Forcing to Emission Uncertainties

    Science.gov (United States)

    Wang, H.; Rasch, P. J.; Easter, R. C.; Singh, B.; Qian, Y.; Ma, P.; Zhang, R.

    2013-12-01

    Carbonaceous aerosol (CA) has been identified as an important but very uncertain forcing agent in the Earth's climate system. It has cascading radiative, microphysical and dynamical effects across the different scales in the atmosphere. Light-absorbing CA (e.g., black carbon (BC) and brown carbon) deposited on snow, sea ice and glaciers can accelerate their melting, which can induce more profound impact through positive feedback mechanisms, having important implications for climate change and fresh water availability at the global and regional scale. Many factors can affect the amount and impacts of CA in a specific region such as the Arctic, among which the global distribution of emissions is of primary importance. There are many uncertainties in global CA emissions, which are changing over time. To better understand the response of climate to these uncertainties and to potential future CA emission changes, it is useful to characterize the global source-receptor relationships and attribute CA loading and radiative forcing to various regional and sectoral CA sources. Observational evidence has clearly demonstrated the occurrence of intercontinental long-range transport of aerosols and to some extent the characteristic transport pathways. However, the observational approach alone cannot provide quantitative information on global source-receptor relationships. We have recently improved the treatment of aerosol transport and wet removal processes in the Community Atmosphere Model version 5 (CAM5) and introduced a brute-force aerosol source tagging technique in which aerosol particles emitted from many independent source regions and sectors are tagged and explicitly tracked. We run the CAM5 model in an 'offline' mode (i.e., driven by reanalysis data) so the transport processes are less likely to be subject to model biases in meteorology and circulation patterns. This modeling tool is used to quantify the characteristics (e.g., burden, surface deposition rate, lifetime

  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 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...

  13. Dosimetric characterization and output verification for conical brachytherapy surface applicators. Part I. Electronic brachytherapy source

    International Nuclear Information System (INIS)

    Purpose: Historically, treatment of malignant surface lesions has been achieved with linear accelerator based electron beams or superficial x-ray beams. Recent developments in the field of brachytherapy now allow for the treatment of surface lesions with specialized conical applicators placed directly on the lesion. Applicators are available for use with high dose rate (HDR)192Ir sources, as well as electronic brachytherapy sources. Part I of this paper will discuss the applicators used with electronic brachytherapy sources; Part II will discuss those used with HDR 192Ir sources. Although the use of these applicators has gained in popularity, the dosimetric characteristics including depth dose and surface dose distributions have not been independently verified. Additionally, there is no recognized method of output verification for quality assurance procedures with applicators like these. Existing dosimetry protocols available from the AAPM bookend the cross-over characteristics of a traditional brachytherapy source (as described by Task Group 43) being implemented as a low-energy superficial x-ray beam (as described by Task Group 61) as observed with the surface applicators of interest. Methods: This work aims to create a cohesive method of output verification that can be used to determine the dose at the treatment surface as part of a quality assurance/commissioning process for surface applicators used with HDR electronic brachytherapy sources (Part I) and192Ir sources (Part II). Air-kerma rate measurements for the electronic brachytherapy sources were completed with an Attix Free-Air Chamber, as well as several models of small-volume ionization chambers to obtain an air-kerma rate at the treatment surface for each applicator. Correction factors were calculated using MCNP5 and EGSnrc Monte Carlo codes in order to determine an applicator-specific absorbed dose to water at the treatment surface from the measured air-kerma rate. Additionally, relative dose

  14. 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

  15. 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...

  16. 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…

  17. 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.

  18. 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.

  19. 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

  20. Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry

    OpenAIRE

    Daellenbach, K. R.; Bozzetti, C.; A. Křepelová; F. Canonaco; Wolf, R.; P. Zotter; P. Fermo; Crippa, M.; Slowik, J. G.; Y. Sosedova; Y. Zhang; R.-J. Huang; L. Poulain; S. Szidat; U. Baltensperger

    2015-01-01

    Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS) have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make impractical its deployment at sufficient sites to determine regional characteristics. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the chara...

  1. 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

  2. Characterization and modeling of earthquake source processes at the Geysers geothermal field

    Science.gov (United States)

    Boyd, O.; Dreger, D. S.; Kim, A.; Gritto, R.

    2013-12-01

    The seismic moment tensor may be interpreted in terms of the orientation of fault structures on which shear dislocation occurs, as well as evidence of dilation. Spatio-temporal source properties including source dimension, area, slip, rupture speed, and slip velocity will be determined using a direct empirical Green's function waveform inversion (Kim, 2009) and using moment-rate time histories of the source from empirical Green's function deconvolution (Dreger, 1997). The outcome will provide a more detailed image of the fracture network inferred from the induced seismicity as well as analysis and determinations of the underlying physical processes of the events (shear dislocations, tensile cracks and non-double-couple volume-compensated sources). The causative fault plane will be determined to better understand the evolution of stress and the role, if any, of conjugate faults in the region. Dreger, D.S., (1997), The Large Aftershocks of the Northridge Earthquake and Their Relationship to Mainshock Slip and Fault-Zone Complexity, Bull. Seism. Soc. Am., 87, p. 1259-1266. Kim, A., Investigating Rupture Process of Parkfield Seismicity, Ph.D. Dissertation, University of California, Berkeley, Fall 2009.

  3. Fabrication and characterization of the source grating for visibility improvement of neutron phase imaging with gratings

    Science.gov (United States)

    Kim, Jongyul; Lee, Kye Hong; Lim, Chang Hwy; Kim, Taejoo; Ahn, Chi Won; Cho, Gyuseong; Lee, Seung Wook

    2013-06-01

    The fabrication of gratings including metal deposition processes for highly neutron absorbing lines is a critical issue to achieve a good visibility of the grating-based phase imaging system. The source grating for a neutron Talbot-Lau interferometer is an array of Gadolinium (Gd) structures that are generally made by sputtering, photo-lithography, and chemical wet etching. However, it is very challenging to fabricate a Gd structure with sufficient neutron attenuation of approximately more than 20 μm using a conventional metal deposition method because of the slow Gd deposition rate, film stress, high material cost, and so on. In this article, we fabricated the source gratings for neutron Talbot-Lau interferometers by filling the silicon structure with Gadox particles. The new fabrication method allowed us a very stable and efficient way to achieve a much higher Gadox filled structure than a Gd film structure, and is even more suitable for thermal polychromatic neutrons, which are more difficult to stop than cold neutrons. The newly fabricated source gratings were tested at the polychromatic thermal neutron grating interferometer system of HANARO at the Korea Atomic Energy Research Institute, and the visibilities and images from the neutron phase imaging system with the new source gratings were compared with those fabricated by a Gd deposition method.

  4. Fabrication and characterization of the source grating for visibility improvement of neutron phase imaging with gratings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jongyul [Neutron Science Division, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Nuclear and Quantum Engineering Department, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); Lee, Kye Hong; Lim, Chang Hwy; Kim, Taejoo [Neutron Science Division, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Ahn, Chi Won [Nano Fusion Technology Division, National Nanofab Center, Daejeon 305-701 (Korea, Republic of); Cho, Gyuseong [Nuclear and Quantum Engineering Department, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); Lee, Seung Wook [School of Mechanical Engineering, Pusan National University, Pusan 609-735 (Korea, Republic of)

    2013-06-15

    The fabrication of gratings including metal deposition processes for highly neutron absorbing lines is a critical issue to achieve a good visibility of the grating-based phase imaging system. The source grating for a neutron Talbot-Lau interferometer is an array of Gadolinium (Gd) structures that are generally made by sputtering, photo-lithography, and chemical wet etching. However, it is very challenging to fabricate a Gd structure with sufficient neutron attenuation of approximately more than 20 {mu}m using a conventional metal deposition method because of the slow Gd deposition rate, film stress, high material cost, and so on. In this article, we fabricated the source gratings for neutron Talbot-Lau interferometers by filling the silicon structure with Gadox particles. The new fabrication method allowed us a very stable and efficient way to achieve a much higher Gadox filled structure than a Gd film structure, and is even more suitable for thermal polychromatic neutrons, which are more difficult to stop than cold neutrons. The newly fabricated source gratings were tested at the polychromatic thermal neutron grating interferometer system of HANARO at the Korea Atomic Energy Research Institute, and the visibilities and images from the neutron phase imaging system with the new source gratings were compared with those fabricated by a Gd deposition method.

  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. 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.

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

    Science.gov (United States)

    Kostenidou, E.; Florou, K.; Kaltsonoudis, C.; Tsiflikiotou, M.; Vratolis, S.; Eleftheriadis, K.; Pandis, S. N.

    2015-10-01

    The concentration and chemical composition of 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 sulfate 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 PM1 was acidic. Positive matrix factorization (PMF) was applied to the high-resolution organic aerosol mass spectra obtained by an Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-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 35 % in Athens) but not dominant.

  8. Characterization of the radon source in North-Central Florida. Final report part 1 -- Final project report; Final report part 2 -- Technical report

    International Nuclear Information System (INIS)

    This report contains two separate parts: Characterization of the Radon Source in North-Central Florida (final report part 1 -- final project report); and Characterization of the Radon Source in North-Central Florida (technical report). The objectives were to characterize the radon 222 source in a region having a demonstrated elevated indoor radon potential and having geology, lithology, and climate that are different from those in other regions of the U.S. where radon is being studied. Radon availability and transport in this region were described. Approaches for predicting the radon potential of lands in this region were developed

  9. 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.

  10. 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.

  11. 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...

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

    OpenAIRE

    Iñigo Verdalet-Guzmán; Laura Martínez-Ortiz; Fernando Martínez-Bustos

    2013-01-01

    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. Th...

  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. 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.

  16. 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)

  17. 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...

  18. 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)

  19. 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)

  20. Multi-technique characterization of neutron fields from moderated 252Cf and 238PuBe sources

    International Nuclear Information System (INIS)

    At the Lawrence Livermore Laboratory, 252Cf and 238PuBe neutron sources are used for calibration of personnel neutron dose meters and neutron monitoring instrumentation. The sources with emission rates of approximately 2x109 and 2x107 n.s-1, respectively, have been calibrated by the United States National Bureau of Standards. The sources are transferred into a 815 m3 concrete calibration cell through a remotely operated pneumatic system. Calibrations can be made without source moderation, or with spherical moderators of aluminium, polyethylene, water or deuterium oxide placed over the end of the pneumatic irradiation tube. The source is located in the tube at one metre above a false floor in the centre of the cell. Nine different moderators are available in sizes up to 56 cm in diameter. Several techniques have been used to characterize the neutron fields produced by each source-moderator configuration to improve the quality of our calibrations. Measurements and calculations have been made to determine neutron flux, kerma rate, neutron spectrum, quality factor, dose equivalent rate and linear energy transfer (LET) spectrum. Neutron spectra are determined by: (1) Calibration using the ANISN discrete ordinates transport code, (2) Bonner sphere measurements using the LOUHI unfolding code, and (3) measurement with proton recoil counters and liquid scintillation detectors. The spectra are then folded into published energy dependent conversion factors to yield kerma, quality factor and dose equivalent values. We obtain LET spectra using a tissue-equivalent LET chamber and the GANDALF unfolding code. Chamber data are used to determine kerma and quality factor. Finally, an 80 cm3 tissue-equivalent ion chamber and neutron-insensitive Geiger counter are used to measure the neutron kerma. Results of the various techniques are presented and compared. In addition, comparisons are made with results obtained from conventional health physics instrumentation such as moderated rem

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

    International Nuclear Information System (INIS)

    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.

  2. Characterization of PM10 sources in the central Mediterranean

    OpenAIRE

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

    2015-01-01

    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 ...

  3. Fluorescence based detection of bioaerosols to improve emissions characterization from environmental sources

    OpenAIRE

    Nasar, Zaheer Ahmad; Tyrrel, Sean F.

    2015-01-01

    Bioaerosols are ubiquitous in ambient air but there have been increasing concerns about their human exposure and to health impact due to ever increasing environmental emissions from sources such as biowaste and intensive agriculture facilities (Borlée et al. 2015). However, the knowledge on their risk of exposure to the public is limited mainly due to a lack of emission characterisation, in part due to the limitation of conventional methods for the detection and characterisation o...

  4. 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

  5. Chemical characterization and source apportionment of submicron aerosol particles with aerosol mass spectrometers

    OpenAIRE

    Carbone, Samara

    2014-01-01

    Fine particles affect climate change in complex ways that are not fully understood and were verified to be harmful to animal and human health. For these reasons information concerning their composition is important to understand their behaviour and to elaborate strategies to mitigate air pollution in urban environments. The overall objective of this study was to investigate in more detail chemical characteristics of ambient particulate matter (PM) and its sources. Studies made in laborat...

  6. 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)

  7. 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.)

  8. 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)

  9. 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

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

    International Nuclear Information System (INIS)

    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)

  11. Sifting Through It All: Characterizing Melanoma Patients' Utilization of the Internet as an Information Source.

    Science.gov (United States)

    Hamilton, Sarah Nicole; Scali, Elena P; Yu, Irene; Gusnowski, Eva; Ingledew, Paris-Ann

    2015-09-01

    This study describes how melanoma patients used the Internet as a melanoma information source and how it impacted their clinical encounter and treatment decision. From 2010 to 2013, melanoma patients were invited to complete a 23-question paper survey with open- and close-ended questions. Thirty-one of the 62 patients approached completed the survey. The majority (90 %) of respondents used the Internet as a melanoma information source. Most (90 %) had used the search engine Google. The most commonly searched topics were melanoma treatment (96 %), screening (64 %), and prevention (64 %). While most respondents (85 %) found the Internet was a useful melanoma information source, over half (54 %) found melanoma websites at least somewhat difficult to understand. Many (78 %) believed it increased their understanding of their diagnosis, 71 % thought it influenced their treatment decision, and 59 % felt it impacted their specialist consultation. This study informs health care professionals that many melanoma patients search the Internet for information regarding their diagnosis and that it may impact their disease understanding and treatment decisions. PMID:25077770

  12. 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)

  13. Automated selection and characterization of emission-line sources in ACS WFC grism data

    CERN Document Server

    Meurer, G R; Gronwall, C; Capak, P; Blakeslee, J P; Ben'itez, N; Ford, H C; Illingworth, G D; Bradley, L D; Pirzkal, N; Walsh, J; Bouwens, R J; Srinivasan, S; Meurer, Gerhardt R.

    2007-01-01

    We present complimentary techniques to find emission-line targets and measure their properties in a semi-automated fashion from grism observations obtained with the Advanced Camera for Surveys aboard the Hubble Space Telescope. The first technique is to find all likely sources in a direct image, extract their spectra and search them for emission lines. The second method is to look for emission-line sources as compact structures in an unsharp masked version of the grism image. Using these methods we identify 46 emission-line targets in the Hubble Deep Field North using a modest (3 orbit) expenditure of HST observing time. Grism spectroscopy is a powerful tool for efficiently identifying interesting low luminosity, moderate redshift emission-line field galaxies. The sources found here have a median i band flux 1.5 mag fainter than the spectroscopic redshift catalog of Cohen et al. They have redshift z 100{\\AA}), and are usually less luminous than the characteristic luminosity at the same redshift. The chief ob...

  14. 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

  15. 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),...

  16. 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...

  17. 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.

  18. Physico-chemical and sensory characterization of a non-conventional food protein source from earthworms

    OpenAIRE

    Cayot, Nathalie; Cayot, Philippe; Bou Maroun, Elias; Laboure, Hélène; Abad Romero, Beatriz; Pernin, Karine; Seller-Alvarez, Nuria; Hernández, Ayary V.; Marquez, Elil; Medina, Ana L.

    2009-01-01

    This study aimed to characterise a non-conventional protein source: a powder made from earthworms, and to evaluate its potential use as human food. The way it was prepared led to low solubility and wide particle size distribution. Sensory analysis was used to assess the acceptability and the organoleptic properties of maize-based pan-cakes fortified with this novel protein powder. Satisfying products were obtained with a substitution level of 5.5% (w/w) earthworm powder in pan-cakes. GC-MS al...

  19. A systematic review characterizing on-farm sources of Campylobacter spp. for broiler chickens.

    Directory of Open Access Journals (Sweden)

    Agnes Agunos

    Full Text Available Campylobacter and antimicrobial-resistant Campylobacter are frequently isolated from broiler chickens worldwide. In Canada, campylobacteriosis is the third leading cause of enteric disease and the regional emergence of ciprofloxacin-resistant Campylobacter in broiler chickens has raised a public health concern. This study aimed to identify, critically appraise, and synthesize literature on sources of Campylobacter in broilers at the farm level using systematic review methodology. Literature searches were conducted in January 2012 and included electronic searches in four bibliographic databases. Relevant studies in French or English (n = 95 conducted worldwide in any year and all study designs were included. Risk of Bias and GRADE criteria endorsed by the Cochrane collaboration was used to assess the internal validity of the study and overall confidence in the meta-analysis. The categories for on-farm sources were: broiler breeders/vertical transfer (number of studies = 32, animals (n = 57, humans (n = 26, environment (n = 54, and water (n = 63. Only three studies examined the antimicrobial resistance profiles of Campylobacter from these on-farm sources. Subgroups of data by source and outcome were analyzed using random effect meta-analysis. The highest risk for contaminating a new flock appears to be a contaminated barn environment due to insufficient cleaning and disinfection, insufficient downtime, and the presence of an adjacent broiler flock. Effective biosecurity enhancements from physical barriers to restricting human movement on the farm are recommended for consideration to enhance local on-farm food safety programs. Improved sampling procedures and standardized laboratory testing are needed for comparability across studies. Knowledge gaps that should be addressed include farm-level drug use and antimicrobial resistance information, further evaluation of the potential for vertical transfer, and improved genotyping

  20. 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

  1. 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

  2. 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

  3. 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.

  4. Characterization and source apportionment of particulate matter Sumatra, 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. PMID:17547168

  5. 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

  6. The extraction and characterization of humic substances from Philippine sources. Part 2: Philippine waters and sediments

    International Nuclear Information System (INIS)

    The humic (HA) and fulvic acids (FA) from freshwater estuarine and marine sediment and water samples were extracted and characterized by ash content, elemental composition and UV-visible and IR spectroscopy. The H/C and N/C atomic ratios for marine sediment HAs were in the range (1.14-1.42) and (0.094-0.160) respectively; the H/C and N/C ratios for freshwater sediment HAs were (1.24-1.30) and (0.074-0.120) respectively. The IR spectra for the FAs showed a greater proportion of polar oxygen containing functional groups compared to the HAs. (author). 21 refs.; 19 figs.; 6 tabs

  7. 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

  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 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

  10. 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.

  11. 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

  12. 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

  13. 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.

  14. Organic geochemical characterization of terrestrial source rocks of the Triassic Madygen formation (Southern Tien Shan, Kyrgyzstan)

    Energy Technology Data Exchange (ETDEWEB)

    Berner, U.; Scheeder, G.; Kus, J. [Section Geochemistry of Petroleum and Coal, BGR, Hannover (Germany); Voigt, S.; Schneider, J.W. [Geological Inst., TU Bergakademic Freiberg (Germany)

    2009-09-15

    Along the northern foothills of the Turkestan-Alai Range (SW Kyrgyzstan), a 1000 to 1500m thick succession of Mesozoic deposits is exposed recording regional changes of the paleo-landscape during Triassic to Cretaceous times. Detailed litho- and biofacies analyses, conducted by the TU Bergakademie Freiberg since 2006, provided for the first time a nearly complete columnar section of the continental Triassic Madygen Formation of Kyrgyzstan. Organic petrographical and organic geochemical methods (including RockEval pyrolyses, and biomarker analyses) have been applied to a suite of terrestrial sedimentary rocks of Triassic age with the intention to identify the depositional environment. Our investigations suggest that the potential source rocks of the terrestrial pluvial Madygen Formation might generate predominantly gaseous hydrocarbons at higher maturities. (orig.)

  15. 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

  16. 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

  17. 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 ...

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

    Energy Technology Data Exchange (ETDEWEB)

    Sexton, Emily [Washington Univ., St. Louis, MO (United States); Snelson, Catherine M [NSTec; Chipman, Veraun D [National Security Technologies, LLC. (NSTec), Mercury, NV (United States); Emer, Dudley [National Security Technologies, LLC. (NSTec), Mercury, NV (United States); White, Bob [National Security Technologies, LLC. (NSTec), Mercury, NV (United States); Emmit, Ryan [National Security Technologies, LLC. (NSTec), Mercury, NV (United States); Wright, Al [National Security Technologies, LLC. (NSTec), Mercury, NV (United States); Drellack, Sigmund [National Security Technologies, LLC. (NSTec), Mercury, NV (United States); Huckins-Gang, Heather [National Security Technologies, LLC. (NSTec), Mercury, NV (United States); Mercadante, Jennifer [National Security Technologies, LLC. (NSTec), Mercury, NV (United States); Floyd, Michael [National Security Technologies, LLC. (NSTec), Mercury, NV (United States); McGowin, Chris [National Security Technologies, LLC. (NSTec), Mercury, NV (United States); Cothrun, Chris [Univ. of Nevada, Las Vegas, NV (United States); Bonal, Nedra [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2013-12-05

    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.

  19. Characterizing sources of nitrate leaching from an irrigated dairy farm in Merced County, California

    Science.gov (United States)

    van der Schans, Martin L.; Harter, Thomas; Leijnse, Anton; Mathews, Marsha C.; Meyer, Roland D.

    2009-11-01

    Dairy farms comprise a complex landscape of groundwater pollution sources. The objective of our work is to develop a method to quantify nitrate leaching to shallow groundwater from different management units at dairy farms. Total nitrate loads are determined by the sequential calibration of a sub-regional scale and a farm-scale three-dimensional groundwater flow and transport model using observations at different spatial scales. These observations include local measurements of groundwater heads and nitrate concentrations in an extensive monitoring well network, providing data at a scale of a few meters and measurements of discharge rates and nitrate concentrations in a tile-drain network, providing data integrated across multiple farms. The various measurement scales are different from the spatial scales of the calibration parameters, which are the recharge and nitrogen leaching rates from individual management units. The calibration procedure offers a conceptual framework for using field measurements at different spatial scales to estimate recharge N concentrations at the management unit scale. It provides a map of spatially varying dairy farming impact on groundwater nitrogen. The method is applied to a dairy farm located in a relatively vulnerable hydrogeologic region in California. Potential sources within the dairy farm are divided into three categories, representing different manure management units: animal exercise yards and feeding areas (corrals), liquid manure holding ponds, and manure irrigated forage fields. Estimated average nitrogen leaching is 872 kg/ha/year, 807 kg/ha/year and 486 kg/ha/year for corrals, ponds and fields respectively. Results are applied to evaluate the accuracy of nitrogen mass balances often used by regulatory agencies to assess groundwater impacts. Calibrated leaching rates compare favorably to field and farm scale nitrogen mass balances. These data and interpretations provide a basis for developing improved management strategies.

  20. Characterization of organic matter source in the sediment of Lake Soyang, in view of land uses.

    Science.gov (United States)

    Kang, Su Jin; Kim, Jung-Hyun; Gal, Jong Ku; Lee, Dong Hun; Lee, Won-Seok; Choi, Jong-Woo; Shin, Kyung Hoon

    2015-04-01

    Stable isotope analysis is applied to surface and core sediment from artificial deep reservoir Soyang, Korea for the identification of sources of organic matters. Carbon and nitrogen stable isotopes of POM(>20μm), the soils of forest area and alpine agriculture area were also analyzed as estimated sources.δ13C of surface sediment were -26.88˜-26.28‰. δ15N were increased from downstream to upstream(2.5˜4.63‰). C/N ratio at downstream were 8˜10, and 16˜22 at upstream. These results indicate that dominance input of the terrestrial organic matters in upstream area. It might be caused by huge delivery of the soil and terrestrial higher plant residue through the turbid current runoff from alpine agriculture area. In contrast, surface sediment of downstream relatively seems to be influenced by algal organic matter. In core sediment collected from the central area of downstream near by a dam, δ13C and δ15N of below 15cm were around -26‰ and 3‰ respectively. However, above the 15cm, δ13C and δ15N trend were increased up to -24.6‰, 5.8‰ respectively. These results demonstrate that forest origin organic matter could be dominant below the 15cm. However, turbid current input has been increased due to the enlarged alpine agriculture area since 1990s. Therefore the soil organic matter derived from alpine agriculture regions should be predominant in the upper sediment of the core. Consequently, in this study, organic matter distribution and its origin in Lake Soyang can be clarified using carbon and nitrogen stable isotope values in additional to lipid biomarker analysis.

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

    International Nuclear Information System (INIS)

    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. 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.

  3. 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...

  4. Characterization factors for water footprint considering the scarcity of green and blue water sources

    Science.gov (United States)

    Oki, T.; Kondo, T.; Pokhrel, Y. N.; Hanasaki, N.

    2011-12-01

    The original concept of virtual water trade was invented to illustrate how much water demand can be reduced by importing food products (Allan 1996), and expanded for meat products and industrial products (Oki and Kanae, 2004). However, there was a confusion between "virtual trade of water" (original) and "trade of virtual water" (misinterpretation but widely accepted), and "virtual water" has been recognized as how much water was used to produce the commodity. Then, the concept has some analogy to carbon footprint (CFP) which is an indicator of total emission of greenhouse gases, and nowadays called water footprint (WFP, Hoekstra, 2004). However, WFP itself is just an inventory of water usages under the framework of life cycle assessment (LCA), and the volume of WFP does not necessary reflect the environmental impacts of water usages because consumptive water use of 100 liter from ground water in arid regions just before rainy season would have more environmental impacts than consumptive water use of 100 liter from rain water in humid regions during snow melt season. In the case of CFP, the emissions of five greenhouse gases except for CO2 were converted into CO2 equivalent volumes by considering the sensitivity for the global warming potential, and summed up into CFP. Here, we propose a new idea objectively determining the weights (characterization factors) for blue water usages, such as from river and ground water, to be converted into green water equivalent in each region and time. The weights are inversely proportional to the area required to obtain the same amount of green water, and water balance model can provide the basic information. The new concept was applied to the WFP of Japan through the imports of major crops. As an inventory, WFP was 15.5 km3/y of rain water, 2.2 km3/y of river water, and 2.0 km3/y of non-renewable and non-local water (NRNL water) for year 2000, however, considering the proposed characterization factors in each region (0.5 x 0

  5. 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

  6. Characterization of a collection of Enterobacter sakazakii isolates from environmental and food sources.

    Science.gov (United States)

    Drudy, Denise; O'Rourke, Michele; Murphy, Mary; Mullane, Niall R; O'Mahony, Rebecca; Kelly, Lorraine; Fischer, Matthias; Sanjaq, Suhad; Shannon, Pauline; Wall, Patrick; O'Mahony, Micheál; Whyte, Paul; Fanning, Séamus

    2006-07-15

    Enterobacter sakazakii has emerged as a rare cause of neonatal meningitis, septicemia and enterocolitis. Contaminated infant milk formula (IMF) has been identified as one infection route. A small number of clinical outbreaks have been epidemiologically linked to IMF contaminated post-pasteurization during manufacture and/or mishandled when reconstituted. Currently no agreed standardized typing protocol has been developed to trace E. sakazakii. The objectives of this study were to apply biochemical and genetic methods to characterize 51 environmental and food E. sakazakii isolates and 6 E. sakazakii type strains. Isolates were presumptively identified using biochemical profiles based on API 20E and ID32E methods and by culture on differential selective Druggan Forsythe Iversen (DFI) agar. Identification was subsequently confirmed by real time polymerase chain reaction (PCR). All but one of the isolates was identified as E. sakazakii by biochemical profiling. One isolate was identified as Escherichia vulneris by ID 32E and as Pantoea agglomerans by API 20E. All isolates produced green/blue colonies on DFI medium characteristic of this organism. Real time PCR could differentiate between E. sakazakii, Enterobacter spp. and other Enterobacteriacae. Analysis of RAPD banding patterns revealed 3 major clusters of E. sakazakii. There was a large degree of diversity noted amongst the remaining isolates. Our findings indicate that RAPD may be applied as a useful and reliable tool for direct comparison of E. sakazakii isolates providing traceability through the infant formula food chain. PMID:16730386

  7. 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.

  8. 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.

  9. Phenolic extracts of Rubus ulmifolius Schott flowers: characterization, microencapsulation and incorporation into yogurts as nutraceutical sources.

    Science.gov (United States)

    Martins, Ana; Barros, Lillian; Carvalho, Ana Maria; Santos-Buelga, Celestino; Fernandes, Isabel P; Barreiro, Filomena; Ferreira, Isabel C F R

    2014-06-01

    Rubus ulmifolius Schott (Rosaceae), known as wild blackberry, is a perennial shrub found in wild and cultivated habitats in Europe, Asia and North Africa. Traditionally, it is used for homemade remedies because of its medicinal properties, including antioxidant activity. In the present work, phenolic extracts of R. ulmifolius flower buds obtained by decoction and hydroalcoholic extraction were chemically and biologically characterized. Several phenolic compounds were identified in both decoction and hydroalcoholic extracts of flowers, ellagitannin derivatives being the most abundant ones, namely the sanguiin H-10 isomer and lambertianin. Additionally, comparing with the decoction form, the hydroalcoholic extract presented both higher phenolic content and antioxidant activity. The hydroalcoholic extract was thereafter microencapsulated in an alginate-based matrix and incorporated into a yogurt to achieve antioxidant benefits. In what concerns the performed incorporation tests, the obtained results pointed out that, among the tested samples, the yoghurt containing the microencapsulated extract presented a slightly higher antioxidant activity, and that both forms (free and microencapsulated extracts) gave rise to products with higher activity than the control. In conclusion, this study demonstrated the antioxidant potential of the R. ulmifolius hydroalcoholic extract and the effectiveness of the microencapsulation technique used for its preservation, thus opening new prospects for the exploitation of these natural phenolic extracts in food applications. PMID:24686891

  10. 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.

  11. Synthesis and characterization cobalt ferrite and evaluation of performance in the transesterification methyl two lipid sources

    International Nuclear Information System (INIS)

    The cottonseed and soybean oils are two lipid matrices that can be used to obtain biodiesel through the use of homogeneous catalysts, which increase operating costs. The use of heterogeneous catalysts can remedy this problem. Thus, this study aimed to evaluate the use of heterogeneous catalyst CoFe2O4 synthesized by combustion reaction in the transesterification of methyl cottonseed oil, soybean and their mixtures (1:1). The sample was characterized by XRD and textural analysis by nitrogen adsorption. The catalytic tests were conducted at 200 deg C, molar ratio of oil:ethanol 1:15, 2% of catalyst and 3 hours. The results show that the synthesis has been effective in obtaining the phase CoFe2O4 with surface area of 23.75 m2 g-1. Tests for transesterification of methyl cottonseed oil, soybean and their blends indicated that the material under study resulted conversions above 50%. The highest efficiency was obtained for the reaction using the mixture of oils. (author)

  12. Occurrence and point source characterization of perfluoroalkyl acids in sewage sludge.

    Science.gov (United States)

    Alder, Alfredo C; van der Voet, Juergen

    2015-06-01

    The occurrence and levels of perfluoroalkyl acids (PFAAs) emitted from specific pollution sources into the aquatic environment in Switzerland were studied using digested sewage sludges from 45 wastewater treatment plants in catchments containing a wide range of potential industrial emitters. Concentrations of individual PFAAs show a high spatial and temporal variability, which infers different contributions from industrial technologies and activities. Perfluorooctane sulfonic acid (PFOS) was generally the predominant PFAA with concentrations varying between 4 and 2440μgkg(-1) (median 75μgkg(-1)). Elevated emissions were especially observed in catchments capturing discharges from metal plating industries (median 82μgkg(-1)), aqueous firefighting foams (median 215μgkg(-1)) and landfill leachates (median 107μgkg(-1)). Some elevated perfluoroalkyl carboxylic acids (PFCAs) levels could be attributed to emissions from textile finishing industries with concentrations up to 233μgkg(-1) in sewage sludge. Assuming sorption to sludge for PFOS and PFCAs of 15% and 2%, respectively, concentrations in wastewater effluents up to the low μgL(-1) level were estimated. Even if wastewater may be expected to be diluted between 10 and 100 times by the receiving waters, elevated concentrations may be reached at specific locations. Although sewage sludge is a minor compartment for PFAAs in WWTPs, these investigations are helpful for the identification of hot-spots from industrial emitters as well as to estimate monthly average concentrations in wastewater. PMID:25176581

  13. Application of a characterized difference-frequency laser source to carbon monoxide trace detection

    International Nuclear Information System (INIS)

    A tunable continuous wave (cw) mid-infrared (MIR) laser based on difference-frequency generation (DFG) in a 1.5-cm long AgGaS2 nonlinear crystal for trace gas detection is reported. Two visible and near-infrared diode lasers were used as pump and signal sources. The MIR-DFG laser was tunable in a wavelength range of 4.75 μm-4.88 μm. The phase-matching (PM) condition was non-critically achieved by adjusting the temperature of the crystal for fixed pairs of input pump and signal wavelengths. The required PM temperatures of the generated MIR-DFG wavelengths have been calculated by using three sets of recent Sellmeier equations and the temperature-dispersion equations of AgGaS2 given by Willer U, et al. (Willer U, Blanke T and Schade W 2001 Appl. Opt. 40 5439). Then the calculated PM temperatures are compared with the experimental values. The performance of the MIR-DFG laser is shown by the trace detection of the P(16) carbon monoxide (12C16O) absorption line in a laboratory-fabricated absorption cell. The enhanced sensitivity of about 0.6×10−4 was obtained through the long path absorption provided by consecutive reflections between coated cylindrical mirrors of a constructed cell. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  14. In situ focus characterization by ablation technique to enable optics alignment at an XUV FEL source

    Czech Academy of Sciences Publication Activity Database

    Gerasimova, N.; Dziarzhytski, S.; Weigelt, H.; Chalupský, Jaromír; Hájková, Věra; Vyšín, Luděk; Juha, Libor

    2013-01-01

    Roč. 84, č. 6 (2013), "065104-1"-"065104-6". ISSN 0034-6748 R&D Projects: GA MŠk ED1.1.00/02.0061; GA MŠk EE.2.3.20.0087; GA ČR(CZ) GAP108/11/1312; GA ČR GAP205/11/0571; GA MŠk EE2.3.30.0057; GA MŠk(CZ) LG13029; GA ČR GAP208/10/2302; GA ČR GA13-28721S Grant ostatní: ELI Beamlines(XE) CZ.1.05/1.1.00/02.0061; OP VK 2 Laser Gen(XE) CZ.1.07/2.3.00/20.0087; OP VK 4 POSTDOK(XE) CZ.1.07/2.3.00/30.0057; AVČR(CZ) M100101221 Institutional support: RVO:68378271 Keywords : free electron laser s * laser ablation * laser beams * optical focusing * ultraviolet sources Subject RIV: BH - Optics, Masers, Laser s Impact factor: 1.584, year: 2013

  15. 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

  16. 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

  17. 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

  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. 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

  20. 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.

  1. 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.

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. X-ray source characterization of aluminum X-pinch plasmas driven by the 0.5 TW LION accelerator

    International Nuclear Information System (INIS)

    Recent experiments at Cornell have been performed to investigate X-pinch plasmas as intense x-ray sources which might be used to pump resonant photoexcitation lasers. Crossed Al wires have been driven by up to 600 kA current for 40 ns. High density bright spots are observed at the crossing point(s). Various diagnostics were used to characterize the X-pinch plasmas as a function of initial mass loading for several specific wire configurations. The optimum mass loading for different ionization stages of Al, and the total x-ray energy yields, which are on the order of hundreds of Joules, were examined. Estimates of plasma density, ∼1020 cm-3, and temperature, about 400 eV, were obtained

  8. 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...

  9. 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

  10. 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

  11. 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.

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

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    Mascali, David; Castro, Giuseppe; Biri, Sándor; Rácz, Richárd; Pálinkás, József; Caliri, Claudia; Celona, Luigi; Neri, Lorenzo; Romano, Francesco Paolo; Torrisi, Giuseppe; Gammino, Santo

    2016-02-01

    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.

  14. 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.

  15. Characterization of radiation sources from the fuel cycle. Applications to the thorium fuel cycle: 232U production in solid fuels

    International Nuclear Information System (INIS)

    The thorium cycle is a good candidate for replacing the current U/Pu cycle since the fissile nucleus of the cycle, 233U, has neutronic properties favourable to a much better regeneration of fissile material in thermal reactors. Moreover, the production of minor actinides is significantly reduced. However, the use of Thorium is only viable if the spent fuel is reprocessed to recover the fissile 233U that does not exist in nature. This reprocessing will involve a heavy industrial infrastructure, particularly since thorium based spent fuel contains small quantities of 232U that is the mother of the hard gamma emitter (208Tl) of 2.6 MeV. The goal of this thesis is, firstly, to study the parameters related to the synthesis of 232U in several kind of fuels and reactors. In a second part, the thesis focuses on the impact on radioprotection of the back end of the fuel in case of switching from the current uranium (U/Pu) cycle to the thorium (Th/U) cycle. For this last purpose, CHARS (Characterization of Radioactive Sources) was developed during this thesis. This code, validated by several benchmarks, handles the calculation of radiation sources in all aspects of the fuel cycle. (author)

  16. 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)

  17. 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

  18. Rapid and reliable seismic source characterization in earthquake early warning systems: current methodologies, results, and new perspectives

    Science.gov (United States)

    Colombelli, Simona; Zollo, Aldo

    2016-04-01

    In the present paper, we provided a review of the main principles and methodologies on which the current earthquake early warning systems are grounded and will also provide a perspective view for next future developments and improvements. First, we introduce the standard methodologies for the source characterization in earthquake early warning, with a special focus on the real-time earthquake magnitude determination. We discuss the suitability of existent methodologies and empirical regression laws for very large events. We then present the different approaches for the rapid prediction of the ground shaking and of the potential damaged zone, both based on traditional seismic data and on the use of continuous GPS data. Finally, the last part of the paper provides the perspective view toward a next generation of early warning systems, linking new research achievements about the earthquake rupture nucleation and the development of new methods/technologies aimed at a fast and high-resolution, real-time modeling of the ongoing source process and accurate prediction of the quake shaking at the regional and local scale.

  19. Neutron activation analysis on sediments from Victoria Land, Antarctica. Multi-elemental characterization of potential atmospheric dust sources

    International Nuclear Information System (INIS)

    The elemental composition of 40 samples of mineral sediments collected in Victoria Land, Antarctica, in correspondence of ice-free sites, is presented. Concentration of 36 elements was determined by instrumental neutron activation analysis, INAA. The selection of 6 standard reference materials and the development of a specific analytical procedure allowed to reduce measurements uncertainties and to verify the reproducibility of the results. The decision to analyze sediment samples from Victoria Land ice-free areas is related to recent investigations regarding mineral dust content in the TALos Dome ICE core (159deg11'E; 72deg49'S, East Antarctica, Victoria Land), in which a coarse local fraction of dust was recognized. The characterization of Antarctic potential source areas of atmospheric mineral dust is the first step to identify the active sources of dust for the Talos Dome area and to reconstruct the atmospheric pathways followed by air masses in this region during different climatic periods. Principal components analysis was used to identify elements and samples correlations; attention was paid specially to rare earth elements (REE) and incompatible/compatible elements (ICE) in respect to iron, which proved to be the most discriminating elemental groups. The analysis of REE and ICE concentration profiles supported evidences of chemical weathering in ice-free areas of Victoria Land, whereas cold and dry climate conditions of the Talos Dome area and in general of East Antarctica. (author)

  20. Advanced process characterization of a 10nm Metal 1 Logic layer using light source modulation and monitoring

    Science.gov (United States)

    Alagna, Paolo; Zurita, Omar; Timoshkov, Vadim; Wong, Patrick; Rechtsteiner, Greg; Baselmans, Jan; Mailfert, Julien; Conley, Will; Hsieh, Simon

    2015-09-01

    As ArF immersion lithography continues to be extended by adopting multi-patterning techniques, imaging requirements continue to become more stringent [1-3]. For multiple patterning based logic devices, the optimal printability is not only driven by the optimization of the optical proximity correction (OPC), but also by complex process factors, such as resist, exposure tool, and mask-related error performance levels. In addition the light source plays a crucial role; it has been widely demonstrated [4-8] how changes in the E95 bandwidth can significantly lead to changes in on wafer patterning due image contrast changes. Cymer has developed novel computational and experimental approaches to enable process characterization studies [9-11]. Using these techniques, simulations were used to assess how E95 bandwidth changes can erode the CDU budget on ≤ 20 nm logic features. Using the results of these simulations, experimental conditions were defined to study the on wafer impact of light source performance on an imec N10 Logic-type test vehicle via six different Metal 1 Logic features. The imaging metrics used to track patterning response are process window (PW), line width roughness (LWR), and local critical dimension uniformity (LCDU).

  1. 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.

  2. Design and characterization of 2.45 GHz electron cyclotron resonance plasma source with magnetron magnetic field configuration for high flux of hyperthermal neutral beam

    International Nuclear Information System (INIS)

    A 2.45 GHz electron cyclotron resonance (ECR) source with a magnetron magnetic field configuration was developed to meet the demand of a hyperthermal neutral beam (HNB) flux on a substrate of more than 1x1015 cm-2 s-1 for industrial applications. The parameters of the operating pressure, ion density, electron temperature, and distance between the neutralization plate and the substrate for the HNB source are specified in a theoretical analysis. The electron temperature and the ion density are measured to characterize the ECR HNB source using a Langmuir probe and optical emission spectroscopy. The parameters of the ECR HNB source are in good agreement with the theoretically specified parameters.

  3. 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

  4. Characterization of neutron flux spectra in the irradiation sites of a 37 GBq 241Am-Be isotopic source

    International Nuclear Information System (INIS)

    Highlights: • An irradiation unit was installed using a 37 GBq 241Am-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 241Am-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 (φth) and epithermal neutron fluxes (φepi), 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 φth = (2.11 ± 0.05) × 103 n cm−2 s−1, φepi = (3.32 ± 0.17) × 101 n cm−2 s−1, f = 63.6 ± 1.5, α = 0.045 ± 0.009, respectively. Similarly, those parameters were measured in site #2 as φth = (1.49 ± 0.04) × 103 n cm−2 s−1, φepi = (2.93 ± 0.15) × 101 n cm−2 s−1, f = 50.9 ± 1.3 and α = 0.038 ± 0.008. The results for f-values indicate

  5. 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

  6. Characterizing Long-term Contaminant Mass Discharge and the Relationship Between Reductions in Discharge and Reductions in Mass for DNAPL Source Areas

    OpenAIRE

    Brusseau, M.L.; Matthieu, D.E.; Carroll, K. C.; Mainhagu, J.; Morrison, C.; McMillan, A; Russo, A; Plaschke, M.

    2013-01-01

    The objective of this study was to characterize the temporal behavior of contaminant mass discharge, and the relationship between reductions in contaminant mass discharge and reductions in contaminant mass, for a very heterogeneous, highly contaminated source-zone field site. Trichloroethene is the primary contaminant of concern, and several lines of evidence indicate the presence of organic liquid in the subsurface. The site is undergoing groundwater extraction for source control, and contam...

  7. 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

  8. 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. PMID:26652398

  9. 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.

  10. 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.

  11. 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.

  12. The use and characterization of a backilluminated charge-coupled device in investigations of pulsed x-ray and radiation sources

    International Nuclear Information System (INIS)

    Examinations of bremsstrahlung and energetic electron beams from a novel laser plasma source motivate and assist characterization of a backthinned, backilluminated direct detection x-ray charge-coupled device (CCD), a topology that is uncommon in hard x-ray work. Behavior toward pseudomonochromatic (55Fe) and multichromatic (241Am) sources is briefly reviewed under optimized noise conditions. Results collectively establish the previously unknown functional depth structure. Several modes of usage are illustrated in ∼4-20 keV x-ray laser plasma source investigations, where the significance of the characterization is briefly discussed. The spectral redistribution associated with this CCD topology is unfavorable, yet appropriate analysis ensures that sufficient spectral information remains for quantitative determination of broadband x-ray flux and spectra in essentially single laser shot measurements. The energy dependence of nascent electron cloud radii in silicon is determined using broadband x-rays from the laser plasma source, turning the narrow depletion depth to advantage. Finally, the characterization is used to quantify recent x-ray spectral explorations of the water jet laser plasma source operating under aspirator vacuum. These results will have key value for establishment of laboratory based ultrafast extended x-ray absorption fine structure experiments using microbolometric detectors.

  13. 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

  14. 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

  15. 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.

  16. Characterization of coronary atherosclerosis by dual-source computed tomography and HU-based color mapping: a pilot study

    International Nuclear Information System (INIS)

    To assess HU-based color mapping for characterization of coronary plaque, using intravascular ultrasound virtual histology (IVUS-VH) as a standard of reference. Dual-source computed tomography and IVUS-VH were prospectively performed in 13 patients. In five lesions, HU thresholds of the color-coding software were calibrated to IVUS-VH. In a 15-lesion verification cohort, volumes of vessel, lumen and plaque or percentages of lipid, fibrous and calcified components were obtained through use of pre-set HU cut-offs as well as through purely visual adjustment of color maps. Calibrated HU ranges for fatty or fibrous plaque, lumen and calcification were -10-69, 70-158, 159-436 and 437+. Using these cut-offs, HU-based analysis achieved good agreement of plaque volume with IVUS (47.0 vs. 51.0 mm3). Visual segmentation led to significant overestimation of atheroma (61.6 vs. 51.0 mm3; P = 0.04) Correlation coefficients for volumes of vessel, lumen and plaque were 0.92, 0.87 and 0.83 with HU-based analysis or 0.92, 0.85 and 0.71 with visual evaluation. With both methods, correlation of percentage plaque composition was poor or insignificant. HU-based plaque analysis showed good reproducibility with intra-class correlation coefficients being 0.90 for plaque volume and 0.81, 0.94 or 0.98 for percentages of fatty, fibrous or calcified components. With use of optimized HU thresholds, color mapping allows for accurate and reproducible quantification of coronary plaque. (orig.)

  17. Source mechanism characterization and integrated interpretation of microseismic data monitoring two hydraulic stimulations in pouce coupe field, Alberta

    Science.gov (United States)

    Lindholm, Garrison J.

    The study of the Pouce Coupe Field is a joint effort between the Reservoir Characterization Project (RCP) and Talisman Energy Inc. My study focuses on the hydraulic stimulation of two horizontal wells within the Montney Formation located in north-western Alberta. The Montney is an example of a modern-day tight, engineering-driven play in which recent advances in drilling of horizontal wells and hydraulic fracturing have made shale gas exploitation economical. The wells were completed in December 2008 and were part of a science driven project in which a multitude of data were collected including multicomponent seismic, microseismic, and production logs. Since this time, a number of studies have been performed by students at Colorado School of Mines to better understand the effects the completions have had on the reservoir. This thesis utilizes the microseismic data that were recorded during the stimulation of the two horizontal wells in order to understand the origin of the microseismic events themselves. The data are then used to understand and correlate to the well production. To gain insight into the source of the microseismic events, amplitude ratios of recorded seismic modes (P, Sh and Sv) for the microseismic events are studied. By fitting trends of simple end member source mechanisms (strike-slip, dip-slip, and tensile) to groups of amplitude ratio data, the events are found to be of strike-slip nature. By comparing the focal mechanisms to other independent natural fracture determination techniques (shear-wave splitting analysis, FMI log), it is shown that the source of recorded microseismic events is likely to be a portion of the shear slip along existing weak planes (fractures) within a reservoir. The technique described in this work is one that is occasionally but increasingly used but offers the opportunity to draw further information from microseismic data using results that are already part of a typical processing workflow. The microseismic events are

  18. 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

  19. Characterization of a Sealed Americium-Beryllium (AmBe) Source by Inductively Coupled Plasma Mass Spectrometry

    International Nuclear Information System (INIS)

    Two Americium-Beryllium neutron sources were dismantled, sampled (sub-sampled) and analyzed via inductively coupled plasma mass spectrometry (ICP-MS). Characteristics such as 'age' since purification, actinide content, trace metal content and inter and intra source composition were determined. The 'age' since purification of the two sources was determined to be 25.0 and 25.4 years, respectively. The systematic errors in the 'age' determination were ± 4 % 2s. The amount and isotopic composition of U and Pu varied substantially between the sub-samples of Source 2 (n=8). This may be due to the physical means of sub-sampling or the way the source was manufactured. Source 1 was much more consistent in terms of content and isotopic composition (n=3 sub-samples). The Be-Am ratio varied greatly between the two sources. Source 1 had an Am-Be ratio of 6.3 ± 52 % (1s). Source 2 had an Am-Be ratio of 9.81 ± 3.5 % (1s). In addition, the trace element content between the samples varied greatly. Significant differences were determined between Source 1 and 2 for Sc, Sr, Y, Zr, Mo, Ba and W.

  20. Characterization and optimization of images acquired by a compact soft X-ray microscope based on a double stream gas-puff target source

    International Nuclear Information System (INIS)

    Using a table-top size soft X-ray (SXR) microscope, based on a laser plasma source with a double stream gas-puff target and a Fresnel zone plate objective, series of images of test samples were acquired. Characterization and optimization of the acquisition parameters were studied and evaluated in terms of signal to noise ratio (SNR). Conclusions for the optimization of SXR imaging were reached. Similar SNR measurements might be performed to characterize other SXR imaging systems as well. Software enabling live calculation of the SNR during the image acquisition might be introduced in future in the compact imaging systems for optimal image acquisition or for benchmarking purposes

  1. Characterization and optimization of images acquired by a compact soft X-ray microscope based on a double stream gas-puff target source

    Science.gov (United States)

    Torrisi, A.; Wachulak, P.; Fahad Nawaz, M.; Bartnik, A.; Węgrzyński, L.; Jancarek, A.; Fiedorowicz, H.

    2016-04-01

    Using a table-top size soft X-ray (SXR) microscope, based on a laser plasma source with a double stream gas-puff target and a Fresnel zone plate objective, series of images of test samples were acquired. Characterization and optimization of the acquisition parameters were studied and evaluated in terms of signal to noise ratio (SNR). Conclusions for the optimization of SXR imaging were reached. Similar SNR measurements might be performed to characterize other SXR imaging systems as well. Software enabling live calculation of the SNR during the image acquisition might be introduced in future in the compact imaging systems for optimal image acquisition or for benchmarking purposes.

  2. 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.

  3. 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).

  4. 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

  5. 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.

  6. 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.

  7. The construction, characterization and use of a low-energy, ultra-high vacuum compatible, metal ion source

    International Nuclear Information System (INIS)

    The design, operation, and use of a low-cost, single grid, electron impact, ultra-high vacuum (UHV) compatible, low-to-medium energy (50-500 eV) ion source capable of operating with medium vapour pressure source material such as Indium is described. (author)

  8. 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.

  9. 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...

  10. 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.

  11. A revised dosimetric characterization of the model S700 electronic brachytherapy source containing an anode-centering plastic insert and other components not included in the 2006 model

    Energy Technology Data Exchange (ETDEWEB)

    Hiatt, Jessica R. [Department of Radiation Oncology, Rhode Island Hospital, The Warren Alpert Medical School of Brown University, Providence, Rhode Island 02903 (United States); Davis, Stephen D. [Department of Medical Physics, McGill University Health Centre, Montreal, Quebec H3G 1A4 (Canada); Rivard, Mark J., E-mail: mark.j.rivard@gmail.com [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)

    2015-06-15

    Purpose: The model S700 Axxent electronic brachytherapy source by Xoft, Inc., was characterized by Rivard et al. in 2006. Since then, the source design was modified to include a new insert at the source tip. Current study objectives were to establish an accurate source model for simulation purposes, dosimetrically characterize the new source and obtain its TG-43 brachytherapy dosimetry parameters, and determine dose differences between the original simulation model and the current model S700 source design. Methods: Design information from measurements of dissected model S700 sources and from vendor-supplied CAD drawings was used to aid establishment of an updated Monte Carlo source model, which included the complex-shaped plastic source-centering insert intended to promote water flow for cooling the source anode. These data were used to create a model for subsequent radiation transport simulations in a water phantom. Compared to the 2006 simulation geometry, the influence of volume averaging close to the source was substantially reduced. A track-length estimator was used to evaluate collision kerma as a function of radial distance and polar angle for determination of TG-43 dosimetry parameters. Results for the 50 kV source were determined every 0.1 cm from 0.3 to 15 cm and every 1° from 0° to 180°. Photon spectra in water with 0.1 keV resolution were also obtained from 0.5 to 15 cm and polar angles from 0° to 165°. Simulations were run for 10{sup 10} histories, resulting in statistical uncertainties on the transverse plane of 0.04% at r = 1 cm and 0.06% at r = 5 cm. Results: The dose-rate distribution ratio for the model S700 source as compared to the 2006 model exceeded unity by more than 5% for roughly one quarter of the solid angle surrounding the source, i.e., θ ≥ 120°. The radial dose function diminished in a similar manner as for an {sup 125}I seed, with values of 1.434, 0.636, 0.283, and 0.0975 at 0.5, 2, 5, and 10 cm, respectively. The radial dose

  12. A search for VHE counterparts of Galactic Fermi bright sources and GeV to TeV spectral characterization

    CERN Document Server

    Tam, P H Thomas; Tibolla, Omar; Chaves, Ryan

    2009-01-01

    Very high-energy (VHE; E>100 GeV) gamma-rays have been detected from a wide range of astronomical objects, such as SNRs, pulsars and pulsar wind nebulae, active galactic nuclei, gamma-ray binaries, molecular clouds, and possibly star-forming regions as well. At lower energies, sources detected using the Large Area Telescope (LAT) aboard Fermi provide a rich set of data which can be used to study the behaviour of cosmic accelerators in the GeV to TeV energy bands. In particular, the improved angular resolution in both bands compared to previous instruments significantly reduces source confusion and facilitates the identification of associated counterparts at lower energies. In this paper, a comprehensive search for VHE gamma-ray sources which are spatially coincident with Galactic Fermi/LAT bright sources is performed, and the available GeV to TeV spectra of coincident sources are compared. It is found that bright LAT GeV sources are correlated to TeV sources, in contrast to previous studies using EGRET data. ...

  13. 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

  14. 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.

  15. Numerical study of atmospheric particulate matters: source apportionment to characterize 3D transport and transformation of precursors and secondary pollutants

    Science.gov (United States)

    Wu, Dongwei

    In recent years, Mainland China, and in particular the industrial hotbed of the Pearl River Delta (PRD) has experienced an increasingly serious problem of high concentrations of airborne particulate matter. Following the tightening-up of China's air quality policies in recent years, and with especially fine particles now added to a new air quality objective, the identification of major source regions and major types of pollutants has become critically important. In this study, a source-oriented method (Particulate Source Apportionment Technology: PSAT) implemented in 3-D Comprehensive Air Quality Model (CAMx), has been applied to analyze how different emission activities impact fine particle concentration in the PRD region. By using this method, a detailed source region and emission category contribution matrix is derived for all regions within the Hong Kong/PRD region. Source appointment results shows that, in summer and spring time, emissions inside PRD region are the major fine particle sources, contribution 70.7% (11.2 mug/m3) and 52.5% (13.1 mug/m3) to the total figure. Super-regional transports are found to be significant in autumn and winter, contribution 58.5% (20.2 mug/m3) and 64.6% (27.8 mug/m3) of the total fine particles in PRD and Hong Kong region. Another important cause of high PM levels has been the transport of fine particles between cities within the PRD region, with three different regions selected for detailed analysis. Results show that mobile vehicle and industry emission are the two major sources for fine particles. Meanwhile, over the same period in Hong Kong, marine proved to be another very significant source of particle pollutant in addition to the significant impact from motor vehicle. Results show that for the Hong Kong/PRD region local reduction of mobile sources and collaboration between different areas could have succeeded in alleviating the air pollution problem.

  16. 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

  17. The characterization and optimization of NIO1 ion source extraction aperture using a 3D particle-in-cell code

    Science.gov (United States)

    Taccogna, F.; Minelli, P.; Cavenago, M.; Veltri, P.; Ippolito, N.

    2016-02-01

    The geometry of a single aperture in the extraction grid plays a relevant role for the optimization of negative ion transport and extraction probability in a hybrid negative ion source. For this reason, a three-dimensional particle-in-cell/Monte Carlo collision model of the extraction region around the single aperture including part of the source and part of the acceleration (up to the extraction grid (EG) middle) regions has been developed for the new aperture design prepared for negative ion optimization 1 source. Results have shown that the dimension of the flat and chamfered parts and the slope of the latter in front of the source region maximize the product of production rate and extraction probability (allowing the best EG field penetration) of surface-produced negative ions. The negative ion density in the plane yz has been reported.

  18. 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...

  19. 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)

  20. Production, characterization and biocompatibility of marine collagen matrices from an alternative and sustainable source : the sea urchin Paracentrotus lividus

    OpenAIRE

    Cristiano Di Benedetto; Alice Barbaglio; Tiziana Martinello; Valentina Alongi; Dario Fassini; Emanuele Cullorà; Marco Patruno; Francesco Bonasoro; Mario Adolfo Barbosa; Maria Daniela Candia Carnevali; Michela Sugni

    2014-01-01

    Collagen has become a key-molecule in cell culture studies and in the tissue engineering field. Industrially, the principal sources of collagen are calf skin and bones which, however, could be associated to risks of serious disease transmission. In fact, collagen derived from alternative and riskless sources is required, and marine organisms are among the safest and recently exploited ones. Sea urchins possess a circular area of soft tissue surrounding the mouth, the peristomial membrane (PM)...

  1. 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 ...

  2. Characterization and source estimation of size-segregated aerosols during 2008-2012 in an urban environment in Beijing

    International Nuclear Information System (INIS)

    Full text: During 2008-2012, size-segregated aerosol samples were collected using an eight-stage cascade impactor at Beijing Normal University (BNU) Site, China. These samples were analyzed using particle induced X-ray emission (PIXE) analysis for concentrations of 21 elements consisting of Mg, AI, Si, P, S, CI, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Ba and Pb. The size-resolved data sets were then analyzed using the positive matrix factorization (PMF) technique in order to identify possible sources and estimate their contribution to particulate matter mass. Nine sources were resolved in eight size ranges (025 ∼ 16μm) and included secondary sulphur, motor vehicles, coal combustion; oil combustion, road dust, biomass burning, soil dust, diesel vehicles and metal processing. PMF analysis of size-resolved source contributions showed that natural sources represented by soil dust and road dust contributed about 57% to the predicted primary particulate matter (PM) mass in the coarse size range(>2μm). On the other hand, anthropogenic sources such as secondary sulphur, coal and oil combustion, biomass burning and motor vehicle contributed about 73% in the fine size range <2μm). The diesel vehicles and secondary sulphur source contributed the most in the ultra-fine size range (<0.25μm) and was responsible for about 52% of the primary PM mass. (author)

  3. 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.

  4. 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

  5. Source attribution of air pollutant concentrations and trends in the southeastern aerosol research and characterization (SEARCH) network.

    Science.gov (United States)

    Blanchard, Charles L; Tanenbaum, Shelley; Hidy, George M

    2013-01-01

    A new approach for determining the contributions of emission sources to trends in concentrations of particulate matter and gases is developed using the chemical mass balance (CMB) method and the U.S. EPA's National Emission Inventory (NEI). The method extends our earlier analysis by using temporally varying emission profiles and includes accounting of primary and secondary particulate organic carbon with an empirical regression calculation. The model offers a potentially important tool for verifying that annual emission reductions by major source category have yielded changes in ambient pollutant concentrations. Using long-term measurements from well-instrumented monitoring sites, observed trends in ambient pollutant concentrations at urban and rural locations can be attributed to emission changes. Trends apportionment is conducted on 2000-2011 ambient monitoring data from the SEARCH network with NEI emissions data adjusted to improve interinventory consistency. The application accounts for major source category influences in southeastern U.S. regional trends; local anomalies are noted. In the SEARCH region, open burning is important as a source of CO and carbonaceous particles. Improved agreement between predicted and measured particulate carbon is obtained by increasing mobile diesel exhaust and area-source particulate carbon emissions by 1 and 20%, respectively, compared with NEI values. The method is general and is applicable to data from any monitoring site that is instrumented for criteria air pollutants, associated gases, and particle composition. PMID:24180677

  6. 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.

  7. 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.

  8. 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.

  9. Identifying and characterizing major emission point sources as a basis for geospatial distribution of mercury emissions inventories

    Science.gov (United States)

    Steenhuisen, Frits; Wilson, Simon J.

    2015-07-01

    Mercury is a global pollutant that poses threats to ecosystem and human health. Due to its global transport, mercury contamination is found in regions of the Earth that are remote from major emissions areas, including the Polar regions. Global anthropogenic emission inventories identify important sectors and industries responsible for emissions at a national level; however, to be useful for air transport modelling, more precise information on the locations of emission is required. This paper describes the methodology applied, and the results of work that was conducted to assign anthropogenic mercury emissions to point sources as part of geospatial mapping of the 2010 global anthropogenic mercury emissions inventory prepared by AMAP/UNEP. Major point-source emission sectors addressed in this work account for about 850 tonnes of the emissions included in the 2010 inventory. This work allocated more than 90% of these emissions to some 4600 identified point source locations, including significantly more point source locations in Africa, Asia, Australia and South America than had been identified during previous work to geospatially-distribute the 2005 global inventory. The results demonstrate the utility and the limitations of using existing, mainly public domain resources to accomplish this work. Assumptions necessary to make use of selected online resources are discussed, as are artefacts that can arise when these assumptions are applied to assign (national-sector) emissions estimates to point sources in various countries and regions. Notwithstanding the limitations of the available information, the value of this procedure over alternative methods commonly used to geo-spatially distribute emissions, such as use of 'proxy' datasets to represent emissions patterns, is illustrated. Improvements in information that would facilitate greater use of these methods in future work to assign emissions to point-sources are discussed. These include improvements to both national

  10. Dosimetric characterization of the GammaClip™169Yb low dose rate permanent implant brachytherapy source for the treatment of nonsmall cell lung cancer postwedge resection

    International Nuclear Information System (INIS)

    Purpose: A novel 169Yb low dose rate permanent implant brachytherapy source, the GammaClip™, was developed by Source Production and Equipment Co. (New Orleans, LA) which is designed similar to a surgical staple while delivering therapeutic radiation. In this report, the brachytherapy source was characterized in terms of “Dose calculation for photon-emitting brachytherapy sources with average energy higher than 50 keV: Report of the AAPM and ESTRO” by Perez-Calatayud et al. [Med. Phys. 39, 2904–2929 (2012)] using the updated AAPM Task Group Report No. 43 formalism.Methods: Monte Carlo calculations were performed using Monte Carlo N-Particle 5, version 1.6 in water and air, the in-air photon spectrum filtered to remove photon energies below 10 keV in accordance with TG-43U1 recommendations and previously reviewed 169Yb energy cutoff levels [D. C. Medich, M. A. Tries, and J. M. Munro, “Monte Carlo characterization of an Ytterbium-169 high dose rate brachytherapy source with analysis of statistical uncertainty,” Med. Phys. 33, 163–172 (2006)]. TG-43U1 dosimetric data, including SK, D-dot (r,θ), Λ, gL(r), F(r, θ), φan(r), and φan were calculated along with their statistical uncertainties. Since the source is not axially symmetric, an additional set of calculations were performed to assess the resulting axial anisotropy.Results: The brachytherapy source's dose rate constant was calculated to be (1.22 ± 0.03) cGy h−1 U−1. The uncertainty in the dose to water calculations, D-dot (r,θ), was determined to be 2.5%, dominated by the uncertainties in the cross sections. The anisotropy constant, φan, was calculated to be 0.960 ± 0.011 and was obtained by integrating the anisotropy factor between 1 and 10 cm using a weighting factor proportional to r−2. The radial dose function was calculated at distances between 0.5 and 12 cm, with a maximum value of 1.20 at 5.15 ± 0.03 cm. Radial dose values were fit to a fifth order polynomial and dual exponential

  11. Assessing the joint impact of DNAPL source-zone behavior and degradation products on the probabilistic characterization of human health risk

    Science.gov (United States)

    Henri, Christopher V.; Fernàndez-Garcia, Daniel; de Barros, Felipe P. J.

    2016-02-01

    The release of industrial contaminants into the subsurface has led to a rapid degradation of groundwater resources. Contamination caused by Dense Non-Aqueous Phase Liquids (DNAPLs) is particularly severe owing to their limited solubility, slow dissolution and in many cases high toxicity. A greater insight into how the DNAPL source zone behavior and the contaminant release towards the aquifer impact human health risk is crucial for an appropriate risk management. Risk analysis is further complicated by the uncertainty in aquifer properties and contaminant conditions. This study focuses on the impact of the DNAPL release mode on the human health risk propagation along the aquifer under uncertain conditions. Contaminant concentrations released from the source zone are described using a screening approach with a set of parameters representing several scenarios of DNAPL architecture. The uncertainty in the hydraulic properties is systematically accounted for by high-resolution Monte Carlo simulations. We simulate the release and the transport of the chlorinated solvent perchloroethylene and its carcinogenic degradation products in randomly heterogeneous porous media. The human health risk posed by the chemical mixture of these contaminants is characterized by the low-order statistics and the probability density function of common risk metrics. We show that the zone of high risk (hot spot) is independent of the DNAPL mass release mode, and that the risk amplitude is mostly controlled by heterogeneities and by the source zone architecture. The risk is lower and less uncertain when the source zone is formed mostly by ganglia than by pools. We also illustrate how the source zone efficiency (intensity of the water flux crossing the source zone) affects the risk posed by an exposure to the chemical mixture. Results display that high source zone efficiencies are counter-intuitively beneficial, decreasing the risk because of a reduction in the time available for the production

  12. 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®

  13. 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...

  14. 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.

  15. Production, Characterization and Biocompatibility of Marine Collagen Matrices from an Alternative and Sustainable Source: The Sea Urchin Paracentrotus lividus

    Directory of Open Access Journals (Sweden)

    Cristiano Di Benedetto

    2014-09-01

    Full Text Available Collagen has become a key-molecule in cell culture studies and in the tissue engineering field. Industrially, the principal sources of collagen are calf skin and bones which, however, could be associated to risks of serious disease transmission. In fact, collagen derived from alternative and riskless sources is required, and marine organisms are among the safest and recently exploited ones. Sea urchins possess a circular area of soft tissue surrounding the mouth, the peristomial membrane (PM, mainly composed by mammalian-like collagen. The PM of the edible sea urchin Paracentrotus lividus therefore represents a potential unexploited collagen source, easily obtainable as a food industry waste product. Our results demonstrate that it is possible to extract native collagen fibrils from the PM and produce suitable substrates for in vitro system. The obtained matrices appear as a homogeneous fibrillar network (mean fibril diameter 30–400 nm and mesh < 2 μm and display remarkable mechanical properties in term of stiffness (146 ± 48 MPa and viscosity (60.98 ± 52.07 GPa·s. In vitro tests with horse pbMSC show a good biocompatibility in terms of overall cell growth. The obtained results indicate that the sea urchin P. lividus can be a valuable low-cost collagen source for mechanically resistant biomedical devices.

  16. Production, characterization and biocompatibility of marine collagen matrices from an alternative and sustainable source: the sea urchin Paracentrotus lividus.

    Science.gov (United States)

    Benedetto, Cristiano Di; Barbaglio, Alice; Martinello, Tiziana; Alongi, Valentina; Fassini, Dario; Cullorà, Emanuele; Patruno, Marco; Bonasoro, Francesco; Barbosa, Mario Adolfo; Carnevali, Maria Daniela Candia; Sugni, Michela

    2014-09-01

    Collagen has become a key-molecule in cell culture studies and in the tissue engineering field. Industrially, the principal sources of collagen are calf skin and bones which, however, could be associated to risks of serious disease transmission. In fact, collagen derived from alternative and riskless sources is required, and marine organisms are among the safest and recently exploited ones. Sea urchins possess a circular area of soft tissue surrounding the mouth, the peristomial membrane (PM), mainly composed by mammalian-like collagen. The PM of the edible sea urchin Paracentrotus lividus therefore represents a potential unexploited collagen source, easily obtainable as a food industry waste product. Our results demonstrate that it is possible to extract native collagen fibrils from the PM and produce suitable substrates for in vitro system. The obtained matrices appear as a homogeneous fibrillar network (mean fibril diameter 30-400 nm and mesh urchin P. lividus can be a valuable low-cost collagen source for mechanically resistant biomedical devices. PMID:25255130

  17. 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

  18. Geochemical and isotopic characterization of the Bodélé Depression dust source and implications for transatlantic dust transport to the Amazon Basin

    Science.gov (United States)

    Abouchami, Wafa; Näthe, Kerstin; Kumar, Ashwini; Galer, Stephen J. G.; Jochum, Klaus Peter; Williams, Earle; Horbe, Adriana M. C.; Rosa, João W. C.; Balsam, William; Adams, David; Mezger, Klaus; Andreae, Meinrat O.

    2013-10-01

    The Bodélé Depression (Chad) in the central Sahara/Sahel region of Northern Africa is the most important source of mineral dust to the atmosphere globally. The Bodélé Depression is purportedly the largest source of Saharan dust reaching the Amazon Basin by transatlantic transport. Here, we have undertaken a comprehensive study of surface sediments from the Bodélé Depression and dust deposits (Chad, Niger) in order to characterize geochemically and isotopically (Sr, Nd and Pb isotopes) this dust source, and evaluate its importance in present and past African dust records. We similarly analyzed sedimentary deposits from the Amazonian lowlands in order to assess postulated accumulation of African mineral dust in the Amazon Basin, as well as its possible impact in fertilizing the Amazon rainforest. Our results identify distinct sources of different ages and provenance in the Bodélé Depression versus the Amazon Basin, effectively ruling out an origin for the Amazonian deposits, such as the Belterra Clay Layer, by long-term deposition of Bodélé Depression material. Similarly, no evidence for contributions from other potential source areas is provided by existing isotope data (Sr, Nd) on Saharan dusts. Instead, the composition of these Amazonian deposits is entirely consistent with derivation from in-situ weathering and erosion of the Precambrian Amazonian craton, with little, if any, Andean contribution. In the Amazon Basin, the mass accumulation rate of eolian dust is only around one-third of the vertical erosion rate in shield areas, suggesting that Saharan dust is "consumed" by tropical weathering, contributing nutrients and stimulating plant growth, but never accumulates as such in the Amazon Basin. The chemical and isotope compositions found in the Bodélé Depression are varied at the local scale, and have contrasting signatures in the "silica-rich" dry lake-bed sediments and in the "calcium-rich" mixed diatomites and surrounding sand material. This

  19. 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 ...

  20. Vaccine-induced plasmablast responses in rhesus macaques: phenotypic characterization and a source for generating antigen-specific monoclonal antibodies

    OpenAIRE

    Silveira, Eduardo L. V.; Kasturi, Sudhir P.; Kovalenkov, Yevgeniy; Ur Rasheed, Ata; Yeiser, Patryce; Jinnah, Zarpheen S.; Legere, Traci H.; Pulendran, Bali; Villinger, Francois; Wrammert, Jens

    2014-01-01

    Over 100 broadly neutralizing antibodies have been isolated from a minority of HIV infected patients, but the steps leading to the selection of plasmacells producing such antibodies remain incompletely understood, hampering the development of vaccines able to elicit them. Rhesus macaques have become a preferred animal model system used to study SIV/HIV, for the characterization and development of novel therapeutics and vaccines as well as to understand pathogenesis. However, most of our knowl...

  1. Production and characterization of glucoamylase from fungus Aspergillus awamori expressed in yeast Saccharomyces cerevisiae using different carbon sources

    OpenAIRE

    Pavezzi, Fabiana Carina; Gomes, Eleni; da Silva, Roberto

    2008-01-01

    Glucoamylase is widely used in the food industry to produce high glucose syrup, and also in fermentation processes for production beer and ethanol. In this work the productivity of the glucoamylase of Aspergillus awamori expressed by the yeast Saccharomyces cerevisiae, produced in submerged fermentation using different starches, was evaluated and characterized physico-chemically. The enzyme presented high specific activity, 13.8 U/mgprotein or 2.9 U/mgbiomass, after 48 h of fermentation using...

  2. 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

  3. 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.

  4. 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

  5. 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

  6. 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...

  7. 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...

  8. External source field characterization and electromagnetic induction response of the deep earth using CHAMP satellite magnetic data

    OpenAIRE

    Venkata Praveen Kumar Kunagu

    2013-01-01

    The steady progresses in the precise measurement of geomagnetic field using land-based observatories and satellites and adapting sophisticated mathematical tools, viz., spherical harmonics, splines, wavelets etc., for data analysis and interpretation, have improved our knowledge about the presence of several contributing sources (both external and internal) in the measured magnetic field. However, for determining a precise global geomagnetic field model, a uniform and full global coverage dat...

  9. Characterizing global statistical significance of spatiotemporal hot spots in magnetoencephalography/electroencephalography source space via excursion algorithms

    OpenAIRE

    Xu, Yang; Sudre, Gustavo P.; Wang, Wei; Weber, Douglas J; Kass, Robert E.

    2011-01-01

    Identifying brain regions with high differential response under multiple experimental conditions is a fundamental goal of functional imaging. In many studies, regions of interest (ROIs) are not determined a priori but are instead discovered from the data, a process that requires care because of the great potential for false discovery. An additional challenge is that magnetoencephalography/electroencephalography sensor signals are very noisy, and brain source images are usually produced by ave...

  10. 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)

  11. Mössbauer and Raman spectroscopy characterization of concretes used in the conditioning of spent radioactive sources

    International Nuclear Information System (INIS)

    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 2+ and Fe 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

  12. 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.

  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. 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.

  15. Lessons Learned from Characterization, Performance Assessment, and EPA Regulatory Review of the 1996 Actinide Source Term for the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    The Waste Isolation Pilot Plant (WIPP) is a US Department of Energy (DOE) facility for the permanent disposal of transuranic waste from defense activities. In 1996, the DOE submitted the Title 40 CFR Part 191 Compliance Certification Application for the Waste Isolation Pilot Plant (CCA) to the US Environmental Protection Agency (EPA). The CCA included a probabilistic performance assessment (PA) conducted by Sandia National Laboratories to establish compliance with the quantitative release limits defined in 40 CFR 191.13. An experimental program to collect data relevant to the actinide source term began around 1989, which eventually supported the 1996 CCA PA actinide source term model. The actinide source term provided an estimate of mobile dissolved and colloidal Pu, Am, U, Th, and Np concentrations in their stable oxidation states, and accounted for effects of uncertainty in the chemistry of brines in waste disposal areas. The experimental program and the actinide source term included in the CCA PA underwent EPA review lasting more than 1 year. Experiments were initially conducted to develop data relevant to the wide range of potential future conditions in waste disposal areas. Interim, preliminary performance assessments and actinide source term models provided insight allowing refinement of experiments and models. Expert peer review provided additional feedback and confidence in the evolving experimental program. By 1995, the chemical database and PA predictions of WIPP performance were considered reliable enough to support the decision to add an MgO backfill to waste rooms to control chemical conditions and reduce uncertainty in actinide concentrations, especially for Pu and Am. Important lessons learned through the characterization, PA modeling, and regulatory review of the actinide source term are (1) experimental characterization and PA should evolve together, with neither activity completely dominating the other, (2) the understanding of physical processes

  16. 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

  17. 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

  18. 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.

  19. 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

  20. Chemical characterization, the transport pathways and potential sources of PM2.5 in Shanghai: Seasonal variations

    Science.gov (United States)

    Zhao, Mengfei; Huang, Zhongsi; Qiao, Ting; Zhang, Yuankai; Xiu, Guangli; Yu, Jianzhen

    2015-05-01

    The 24-h PM2.5 samples were collected at the site of East China University of Science and Technology (ECUST) in Shanghai from 2011 to 2012, representing winter, spring, summer and autumn, respectively. And PM2.5 and its chemical components including organic carbon (OC), elemental carbon (EC), water-soluble organic carbon (WSOC), humic-like substance carbon (HULIS-C) and water-soluble ions were analyzed. The results suggested that the average PM2.5 concentrations were (70.35 ± 43.75) μg/m3, (69.76 ± 38.67) μg/m3, (51.26 ± 28.25) μg/m3 and (82.37 ± 48.70) μg/m3 in winter, spring, summer and autumn, respectively. Secondary inorganic ions (sulfate, nitrate and ammonium) were the dominant pollutants of PM2.5 in the four seasons. Total carbon (TC) was an important component explaining above 15% of PM2.5. OC/EC ratios were all above 2 ranging from 4.31 to 6.35; particularly in winter it reached the highest 6.35 which demonstrated that secondary organic carbon (SOC) should be a significant composition of PM2.5. The SOC calculated based on the OC/EC ratio method had stronger correlation with WSOC in summer and autumn (summer: R2 = 0.73 and autumn: R2 = 0.75). The HULIS-C and SOC most significantly correlated in autumn (R2 = 0.83). The data showed that PM2.5 atmospheric aerosols were more acidic in autumn and the concentrations of PM2.5 and its chemical components were much higher. Factor analysis (FA), cluster analysis of air mass back trajectories, potential source contribution function (PSCF) model and concentration weighted trajectory (CWT) model were used to investigate the transport pathways and identify potential source areas of PM2.5 in different seasons. FA identified various sources of PM2.5: secondary aerosol reactions, the aged sea salts and road dusts. The results of cluster analysis, PSCF model and CWT model demonstrated that the local sources in the Yangtze River Delta Region (YRDR) made significant contributions to PM2.5. During winter and autumn long

  1. Physico-chemical characterization of lignins from different sources for use in phenol-formaldehyde resin synthesis.

    Science.gov (United States)

    Tejado, A; Peña, C; Labidi, J; Echeverria, J M; Mondragon, I

    2007-05-01

    During the last decades lignin has been investigated as a promising natural alternative to petrochemicals in phenol-formaldehyde (PF) resin production, due to their structural similarity. Physico-chemical characterization of three types of lignin, namely kraft pine lignin (L1), soda-anthraquinone flax lignin (L2), and ethanol-water wild tamarind lignin (L3) has been evaluated to determine which one is the most suitable chemical structure for above purpose. Characterization has been performed using Fourier transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance spectrometry ((1)H NMR) to analyse the chemical structure, gel permeation chromatography (GPC) for determining molecular weight (MW) and molecular weight distribution (MWD), differential scanning calorimetry (DSC) to measure the glass transition temperature and thermogravimetric analysis (TGA) to follow the thermal degradation. Both structural and thermal characteristics suggest that kraft pine lignin (L1) would be a better phenol (P) substitute in the synthesis of lignin-phenol-formaldehyde (LPF) resins, as it presents higher amounts of activated free ring positions, higher MW and higher thermal decomposition temperature. PMID:16843657

  2. Characterization of charge carrier collection in a CdZnTe Frisch collar detector with a highly collimated 137Cs source

    International Nuclear Information System (INIS)

    A 4.7 x4.7x9.5 mm3 CdZnTe Frisch collar device was characterized through probing the device with a highly collimated 137Cs 662 keV gamma ray source. In a systematic series of experiments, the detector was probed along the length and width with a 137Cs gamma ray source using a 43.0 mm long Pb-collimator with a 0.6 mm circular hole. The detector was probed along the central line under different operating voltages of 1200, 1000, 800, 600 and 400 V. The experimental results correlated well to charge collection calculations for a modeled device with the same size and operating conditions. It was proved that, unlike the planar configuration, the charge collection efficiency profile along the length of Frisch collar device is considerably improved. The CdZnTe raw materials for this study were acquired from Redlen Technologies, and the Frisch collar device was fabricated and characterized at S.M.A.R.T. Laboratory at Kansas State University.

  3. 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

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. 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

  19. 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 HI 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 HI distributions over large cosmological volumes. Such synthetic data products can be used to guide observing and data handling/analysis strategies for forthcoming HI galaxy surveys. As a demonstration of the potential use of our simulated products we use them to conduct several mock HI 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 over-estimates of Omega_HI by some recent HI stacking experiments. Our simulations will allow the study of subtle redshift-dependent effects in future stacking analyses.

  20. 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.

  1. 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.

  2. 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.

  3. Heated blends of phosphate waste: Microstructure characterization, effects of processing factors and use as a phosphorus source for alfalfa growth.

    Science.gov (United States)

    Loutou, M; Hajjaji, M; Mansori, M; Favotto, C; Hakkou, R

    2016-07-15

    Microstructure of expandable lightweight aggregates (LWAs), which was composed of phosphate waste (PW), cement kiln dust (CKD) and raw clay (RC) was investigated, and the effects of processing factors (temperature, waste content, soaking time) on their physical properties were quantified by using response surface methodology (RSM). The potential use of LWAs as a phosphorus source was assessed through the use of seeds of alfalfa. It was found that the main minerals of the waste, namely carbonates and fluorapatite, were involved in the formation of labradorite/anorthite and melt respectively. Stability of mullite- the main constituent of CKD- was sensitive to the melt content. The assemblage of the identified phases was discussed based on the CaO-SiO2-Al2O3 phase diagram. The results of RSM showed that the change of compressive strength, firing shrinkage and water absorption of LWAs versus processing factors was well described with a polynomial model and the weights of the effects of the factors increased in the following order: sintering temperature > waste content (in the case of PW-RC) > soaking time. On the other hand, it was found that due to the release of phosphorus by soil-embedded pellets, the growth of alfalfa plants improved, and the rate enhanced in this order: PW-RC > PW-CKD > PW-CKD-RC. The absorbed quantity of phosphorus (0.12%) was still lower than the common uptake amount. PMID:27100329

  4. Waste oil shale ash as a novel source of calcium for precipitated calcium carbonate: Carbonation mechanism, modeling, and product characterization

    International Nuclear Information System (INIS)

    Highlights: → A method for converting oil shale waste ash into precipitated CaCO3 is elucidated. → We discuss the mechanism of hazardous alkaline ash leachates carbonation. → We report a model describing precipitation of CaCO3 from multi-ionic ash leachates. → Model enables simulation of reactive species concentration profiles. → Product contained ∼96% CaCO3 with 4-10 μm size calcite or/and vaterite particles. - Abstract: In this paper, a method for converting lime-containing oil shale waste ash into precipitated calcium carbonate (PCC), a valuable commodity is elucidated. The mechanism of ash leachates carbonation was experimentally investigated in a stirred semi-batch barboter-type reactor by varying the CO2 partial pressure, gas flow rate, and agitation intensity. A consistent set of model equations and physical-chemical parameters is proposed to describe the CaCO3 precipitation process from oil shale ash leachates of complex composition. The model enables the simulation of reactive species (Ca2+, CaCO3, SO42-, CaSO4, OH-, CO2, HCO3-, H+, CO32-) concentration profiles in the liquid, gas, and solid phases as well as prediction of the PCC formation rate. The presence of CaSO4 in the product may also be evaluated and used to assess the purity of the PCC product. A detailed characterization of the PCC precipitates crystallized from oil shale ash leachates is also provided. High brightness PCC (containing up to ∼96% CaCO3) with mean particle sizes ranging from 4 to 10 μm and controllable morphology (such as rhombohedral calcite or coexisting calcite and spherical vaterite phases) was obtained under the conditions studied.

  5. 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).

  6. 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).

  7. 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.

  8. Further biogeochemical characterization of a trichloroethene-contaminated fractured dolomite aquifer: Electron source and microbial communities involved in reductive dechlorination

    Science.gov (United States)

    Hohnstock-Ashe, A. M.; Plummer, S.M.; Yager, R.M.; Baveye, P.; Madsen, E.L.

    2001-01-01

    A recent article presented geochemical and microbial evidence establishing metabolic adaptation to and in-situ reductive dechlorination of trichloroethene (TCE) in a fractured dolomite aquifer. This study was designed to further explore site conditions and microbial populations and to explain previously reported enhancement of reductive dechlorination by the addition of pulverized dolomite to laboratory microcosms. A survey of groundwater geochemical parameters (chlorinated ethenes, ethene, H2, CH4, DIC, DOC, and ??13C values for CH4, DIC, and DOC) indicated that in situ reductive dechlorination was ongoing and that an unidentified pool of organic carbon was contributing, likely via microbial respiration, to the large and relatively light onsite DIC pool. Petroleum hydrocarbons associated with the dolomite rock were analyzed by GC/MS and featured a characteristically low ??13C value. Straight chain hydrocarbons were extracted from the dolomite previously found to stimulate reductive dechlorination; these were particularly depleted in hexadecane (HD). Thus, we hypothesized that HD and related hydrocarbons might be anaerobically respired and serve both as the source of onsite DIC and support reductive dechlorination of TCE. Microcosms amended with pulverized dolomite demonstrated reductive dechlorination, whereas a combusted dolomite amendment did not. HD-amended microcosms were also inactive. Therefore, the stimulatory factor in the pulverized dolomite was heat labile, but that component was not HD. Amplified Ribosomal DNA Restriction Analysis (ARDRA) of the microbial populations in well waters indicated that a relatively low diversity, sulfur-transforming community outside the plume was shifted toward a high diversity community including Dehalococcoides ethenogenes-type microorganisms inside the zone of contamination. These observations illustrate biogeochemical intricacies of in situ reductive dechlorination reactions.

  9. Characterization of the world's first nuclear explosion, the Trinity test, as a source of public radiation exposure.

    Science.gov (United States)

    Widner, Thomas E; Flack, Susan M

    2010-03-01

    The world's first atomic bomb was tested in New Mexico on 16 July 1945. From 1999 through 2008, scientists working for the Centers for Disease Control and Prevention gathered information relevant to past releases from Los Alamos activities, including the Trinity test. Detonation on a 30.5 m tower enhanced radioactive fallout, and terrain and wind patterns caused "hot spots" of deposition. Several ranchers reported that fallout resembling flour was visible for 4 to 5 d after the blast, and residents living as close as 19 km from ground zero collected rain water from metal roofs for drinking. Pressures to maintain secrecy and avoid legal claims led to decisions that would not likely have been made in later tests. Residents were not warned before the test or informed afterward about potential protective actions, and no evacuations were conducted. Occupied homes were overlooked on the day of the blast. Exposure rates in residential areas were recorded as high as 1.4 microC kg s (20 R h) using instruments that were crude, ill suited to field use, and incapable of effectively measuring alpha contamination from about 4.8 kg of unfissioned plutonium that was dispersed. Vehicle shielding and contamination were recognized but not corrected for. To date, the post-shot field team measurements have not been rigorously evaluated, cross-checked, adjusted, or subjected to uncertainty analysis. Evaluations of Trinity fallout published to date have not addressed internal doses to members of the public following intakes of contaminated air, water, or foods. The closing of these data gaps appears feasible with the information that has been assembled and would support placement of the Trinity event in perspective as a source of public radiation exposure and more defensible evaluation of the potential for human health effects. PMID:20147790

  10. 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

  11. 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

  12. Identification and characterization of scenarios of natural source, representation of the same ones by means of radiological maps

    International Nuclear Information System (INIS)

    The National Network of Environmental Radiological Surveillance of the Cuba Republic (NNERS) between their main functions of controlling permanently, from the radiological point of view, the environment in the whole national territory, monitoring, among other indicators, the environmental gamma dose rate. This monitoring is carried out in 18 radiological posts distributed by the whole country that gives us an idea of the atmospheric gamma background of a certain region. The influence of the natural sources scenarios in the measurement of the gamma dose rate, results in the variability of the measurement inside oneself region and even in distances so short as 500 meters the variation can be between the 30 or 40 nGy/h, for that, when we estimate the exhibition dose to which the population is subjected, we would introduce a great error when we take like base the gamma dose rate of the region in study. The study of the environmental gamma background was carried out in Havana City, using a mobile gamma dose rate system, with a high sensibility and a very low time of answer. The used system is able to register in real time the position and the gamma dose rate. The monitoring carries out from an automobile, using an interval of measurement of 10 seconds. The obtained results are classified by measurements ranges, and they were associated to different codes of colors and were showed in a map for a better interpretation and visualization of the same ones. Computer tools were developed for do that. The average value of dose rate in Havana City (taking into account the contribution of the cosmic radiation) is 55,6 nGy/h, similar to the national historical average reported by the NNERS that is of 55,3 nGy/h. The municipality of higher dose rate was Cerro with 61,3 nGy/h, and that of lower value was San Miguel del Padron with 51,9 nGy/h. If we discard the contribution of the cosmic radiation, the dose rate in air in Havana City is below 50 % of the world average. (author)

  13. 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

  14. 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

  15. Design, hard x-ray source characterization and applications of a plasma focus tailored for flash hard x-ray imaging

    International Nuclear Information System (INIS)

    A low-energy (2.5 kJ and 30 kV) plasma focus tailored to perform as a hard x-ray radiation source for flash radiography, is presented. The device is operated in a mixture of deuterium and argon to enhance its performance. A study of the breakdown properties of the discharge chamber is presented. The hard x-ray emission was experimentally characterized by means of both: (i) the spatial location of the radiation source inside the discharge chamber and (ii) an effective energy analysis based on systematic measurements of the attenuation of the hard x-ray output through different metallic pieces. Samples of cadmium, copper and nickel with thicknesses in the range 1-6 mm were employed. From single shot images of the set of plates, the effective energy of the radiation was estimated to be around 83 keV. Numerical calculations, based on validated codes, are presented to give an interpretation of the experimental results. Experimental demonstration of the suitability for hard x-ray imaging applications is also presented.

  16. Characterization of the CW starter plasma RF matching network for operating the SNS H{sup −} ion source with lower H{sub 2} flows

    Energy Technology Data Exchange (ETDEWEB)

    Han, B. X., E-mail: hanb@ornl.gov; Stockli, M. P.; Kang, Y.; Piller, C.; Murray, S. N.; Pennisi, T. R.; Santana, M.; Welton, R. F. [Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2016-02-15

    The Spallation Neutron Source H{sup −} ion source is operated with a pulsed 2-MHz RF (50-60 kW) to produce the 1-ms long, ∼50 mA H{sup −} beams at 60 Hz. A continuous low power (∼300 W) 13.56-MHz RF plasma, which is initially ignited with a H{sub 2} pressure bump, serves as starter plasma for the pulsed high power 2-MHz RF discharges. To reduce the risk of plasma outages at lower H{sub 2} flow rates which is desired for improved performance of the following radio frequency quadrupole, the 13.56-MHz RF matching network was characterized over a broad range of its two tuning capacitors. The H-α line intensity of the 13.56-MHz RF plasma and the reflected power of the 13.56-MHz RF were mapped against the capacitor settings. Optimal tunes for the maximum H-α intensity are consistent with the optimal tunes for minimum reflected power. Low limits of the H{sub 2} flow rate not causing plasma outages were explored within the range of the map. A tune region that allows lower H{sub 2} flow rate has been identified, which differs from the optimal tune for global minimum reflected power that was mostly used in the past.

  17. Characterization of the CW starter plasma RF matching network for operating the SNS H- ion source with lower H2 flows

    Science.gov (United States)

    Han, B. X.; Stockli, M. P.; Kang, Y.; Piller, C.; Murray, S. N.; Pennisi, T. R.; Santana, M.; Welton, R. F.

    2016-02-01

    The Spallation Neutron Source H- ion source is operated with a pulsed 2-MHz RF (50-60 kW) to produce the 1-ms long, ˜50 mA H- beams at 60 Hz. A continuous low power (˜300 W) 13.56-MHz RF plasma, which is initially ignited with a H2 pressure bump, serves as starter plasma for the pulsed high power 2-MHz RF discharges. To reduce the risk of plasma outages at lower H2 flow rates which is desired for improved performance of the following radio frequency quadrupole, the 13.56-MHz RF matching network was characterized over a broad range of its two tuning capacitors. The H-α line intensity of the 13.56-MHz RF plasma and the reflected power of the 13.56-MHz RF were mapped against the capacitor settings. Optimal tunes for the maximum H-α intensity are consistent with the optimal tunes for minimum reflected power. Low limits of the H2 flow rate not causing plasma outages were explored within the range of the map. A tune region that allows lower H2 flow rate has been identified, which differs from the optimal tune for global minimum reflected power that was mostly used in the past.

  18. 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

  19. 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

  20. 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...

  1. 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)

  2. 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

  3. 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.

  4. 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.

  5. West Texas array experiment: Noise and source characterization of short-range infrasound and acoustic signals, along with lab and field evaluation of Intermountain Laboratories infrasound microphones

    Science.gov (United States)

    Fisher, Aileen

    The term infrasound describes atmospheric sound waves with frequencies below 20 Hz, while acoustics are classified within the audible range of 20 Hz to 20 kHz. Infrasound and acoustic monitoring in the scientific community is hampered by low signal-to-noise ratios and a limited number of studies on regional and short-range noise and source characterization. The JASON Report (2005) suggests the infrasound community focus on more broad-frequency, observational studies within a tactical distance of 10 km. In keeping with that recommendation, this paper presents a study of regional and short-range atmospheric acoustic and infrasonic noise characterization, at a desert site in West Texas, covering a broad frequency range of 0.2 to 100 Hz. To spatially sample the band, a large number of infrasound gauges was needed. A laboratory instrument analysis is presented of the set of low-cost infrasound sensors used in this study, manufactured by Inter-Mountain Laboratories (IML). Analysis includes spectra, transfer functions and coherences to assess the stability and range of the gauges, and complements additional instrument testing by Sandia National Laboratories. The IMLs documented here have been found reliably coherent from 0.1 to 7 Hz without instrument correction. Corrections were built using corresponding time series from the commercially available and more expensive Chaparral infrasound gauge, so that the corrected IML outputs were able to closely mimic the Chaparral output. Arrays of gauges are needed for atmospheric sound signal processing. Our West Texas experiment consisted of a 1.5 km aperture, 23-gauge infrasound/acoustic array of IMLs, with a compact, 12 m diameter grid-array of rented IMLs at the center. To optimize signal recording, signal-to-noise ratio needs to be quantified with respect to both frequency band and coherence length. The higher-frequency grid array consisted of 25 microphones arranged in a five by five pattern with 3 meter spacing, without

  6. Identification and characterization of five non-traditional-source categories: Catastrophic/accidental releases, vehicle repair facilities, recycling, pesticide application, and agricultural operations. Final report, September 1991-September 1992

    International Nuclear Information System (INIS)

    The work 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 Plans (SIP) area source methodologies and to develop appropriate emissions estimation methodologies and emission factors for a group of these source categories. Based on the results of the identification and characterization portions of the research, five source categories were selected for methodology and emission factor development: catastrophic/accidental releases, vehicle repair facilities, recycling, pesticide application and agricultural operations. The report presents emissions estimation methodologies and emission factor data for the selected source categories. The discussions for each selected category include general background information, emissions generation activities, pollutants emitted, sources of activity and pollutant data, emissions estimation methodologies, issues to be considered and recommendations. The information used in these discussions was derived from various sources including available literature, industrial and trade association publications and contracts, experts on the category and activity, and knowledgeable federal and state personnel

  7. 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

  8. Experimental characterization of the Advanced Liquid Hydrogen Cold Neutron Source spectrum of the NBSR reactor at the NIST Center for Neutron Research

    Energy Technology Data Exchange (ETDEWEB)

    Cook, J.C.; Barker, J.G.; Rowe, J.M.; Williams, R.E. [NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Drive, Mail Stop 6100, Gaithersburg, MD 20899-6100 (United States); Gagnon, C. [Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742 (United States); Lindstrom, R.M. [Scientist Emeritus, Chemical Sciences Division, National Institute of Standards and Technology, 100 Bureau Drive, Mail Stop 8395, Gaithersburg, MD 20899-8395 (United States); Ibberson, R.M.; Neumann, D.A. [NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Drive, Mail Stop 6100, Gaithersburg, MD 20899-6100 (United States)

    2015-08-21

    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.

  9. Characterization and sources of regional-scale transported carbonaceous and dust aerosols from different pathways in coastal and sandy land areas of China

    Science.gov (United States)

    Zhang, X. Y.; Wang, Y. Q.; Wang, D.; Gong, S. L.; Arimoto, R.; Mao, L. J.; Li, J.

    2005-08-01

    Concentrations of 12-hour averaged organic carbon (OC), elemental carbon (EC), and other trace elements were determined from bulk aerosol samples at a coastal city of Lian Yun Gang (LYG) in east China from June to December 2003 and a sandy land site of Tong Liao in northeast China from June to August 2003. Regional transports from four main source areas accounted for ˜35-49% of the Asian dust and 16-18% of the carbonaceous particles for both sites. The regional mean concentrations of various species, especially EC, were comparable to or lower than those in urban areas of inland China, Korea, and Japan but tended to be higher than those in Hong Kong or rural sites in east Asia. At LYG, OC showed a clear seasonal pattern with a peak loading in winter (24 μg m-3) and a low in summer (10 μg m-3). Seasonality of EC was more pronounced than that of OC with a difference of approximately threefold (3.8 to 11 μg m-3). Three types of air masses with high particulate loadings were found to be responsible for the peak EC and low OC/EC ratios in winter. Clean air masses with more than 50% secondary organic carbon contents were largely of marine origins. Elemental concentrations (Ca, Fe, K, Mn, and Ti) were mainly associated with Asian dust aerosols with a certain fraction of K from biomass burning in mainland China characterized with a ratio of 1.3 for OC/K.

  10. 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.

  11. 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

    2015-08-15

    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 concentrations present 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. PMID:25917777

  12. 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.

  13. 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

  14. 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

  15. 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

  16. Integrated characterization of natural attenuation of a PCE plume after thermal remediation of the source zone - incl. dual isotope and microbial techniques

    OpenAIRE

    Broholm, Mette Martina

    2015-01-01

    PCE DNAPL contamination at the former central dry cleaning facility in Rødekro, Denmark, was subject to thermal (steam) source zone remediation in late 2006. A > 2 km long plume of chlorinated ethenes (PCE and chlorinated degradation products) which has migrated downgradient from the source zone has not undergone active remediation. A study of the natural degradation within the plume prior to source treatment including stable isotope monitoring was conducted in 2006(-2007) by Hunkeler et a...

  17. 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.

  18. 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...

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. SU-F-19A-05: Experimental and Monte Carlo Characterization of the 1 Cm CivaString 103Pd Brachytherapy Source

    International Nuclear Information System (INIS)

    Purpose: To determine the in-air azimuthal anisotropy and in-water dose distribution for the 1 cm length of the CivaString 103Pd brachytherapy source through measurements and Monte Carlo (MC) simulations. American Association of Physicists in Medicine Task Group No. 43 (TG-43) dosimetry parameters were also determined for this source. Methods: The in-air azimuthal anisotropy of the source was measured with a NaI scintillation detector and simulated with the MCNP5 radiation transport code. Measured and simulated results were normalized to their respective mean values and compared. The TG-43 dose-rate constant, line-source radial dose function, and 2D anisotropy function for this source were determined from LiF:Mg,Ti thermoluminescent dosimeter (TLD) measurements and MC simulations. The impact of 103Pd well-loading variability on the in-water dose distribution was investigated using MC simulations by comparing the dose distribution for a source model with four wells of equal strength to that for a source model with strengths increased by 1% for two of the four wells. Results: NaI scintillation detector measurements and MC simulations of the in-air azimuthal anisotropy showed that ≥95% of the normalized data were within 1.2% of the mean value. TLD measurements and MC simulations of the TG-43 dose-rate constant, line-source radial dose function, and 2D anisotropy function agreed to within the experimental TLD uncertainties (k=2). MC simulations showed that a 1% variability in 103Pd well-loading resulted in changes of <0.1%, <0.1%, and <0.3% in the TG-43 dose-rate constant, radial dose distribution, and polar dose distribution, respectively. Conclusion: The CivaString source has a high degree of azimuthal symmetry as indicated by the NaI scintillation detector measurements and MC simulations of the in-air azimuthal anisotropy. TG-43 dosimetry parameters for this source were determined from TLD measurements and MC simulations. 103Pd well-loading variability results in

  5. Characterizing spatial distribution and sources of heavy metals in the soils from mining-smelting activities in Shuikoushan, Hunan Province, China.

    Science.gov (United States)

    Wei, Chaoyang; Wang, Cheng; Yang, Linsheng

    2009-01-01

    The spatial variation of heavy metals in the soils in Shuikoushan mining-smelting area, Hunan Province, China, was investigated using multivariate and geo-statistic analysis. A total of 106 composite soil samples were collected in an area of about 100 km2. Concentrations of total As, Cd, Pb, Zn, Cu and Cr were measured using inductively coupled plasma mass spectrometry (ICP-MS). Arsenic and Pb were found to have a common source, indicating the same sources and spreading processes, such as aerosols and airborne particulates from smelting chimneys. Airborne sources from smelting chimneys contributed greatly to Cd in the area, which demonstrated the same dispersion pattern as As and Pb. However, two hot spots of Cd around smelters were possibly enlarged by wastewaters, demonstrating another important source of Cd in Shuikouhsan. Geo-statistic interpolated mapping demonstrated that hot-spots of Zn were only found proximal to the large smelters, suggesting that Zn primarily came from the chimneys of larger smelters. The major Cu hot-spots appeared closely to the tailing dam, indicating that weathering and leaching of tailings were the major sources of Cu contamination in Shuikoushan. Our findings indicated that airborne volatile particles and aerosols contributed the most to As, Cd, Pb, Zn and Cu contamination, while Cd and Cu may also derive from the discharge of wastewater from smelters and the leaching of tailings, respectively. PMID:19999971

  6. Characterization and source identification of fine particulate matter in the atmosphere of downtown Shanghai using μ-SXRF and ICP-MS

    International Nuclear Information System (INIS)

    To investigate the characteristic and sources of the fine particulate matter (PM2.5), and the major sources affecting particulate air pollution in Shanghai, China, the individual aerosol particles were analyzed using the synchrotron radiation micro-beam X-ray fluorescence analysis (μ-SXRF), and the PM2.5 multi-elements were determined by the inductively coupled plasma mass spectrometer (ICP-MS). The results show that the mass concentration and chemical elements have seasonal variation, and the enrichment factors show that the chemical elements in the inhalable particles could come from the earth crust and anthropogenic pollution. The extent of metal pollution was assessed by comparing the measured concentrations with those reported in the literature. Nine categories of PM2.5 pollution sources identified at the center of Shanghai show that the vehicle exhaust, emission of metallurgic industry and coal combustion are important. (authors)

  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. PMID:26899429

  8. 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

  9. 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)

  10. 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-...

  11. 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.

  12. Characterization of a cold cathode Penning ion source for the implantation of noble gases beneath 2D monolayers on metals: Ions and neutrals

    International Nuclear Information System (INIS)

    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

  13. 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.

  14. CHARACTERIZING LENSES AND LENSED STARS OF HIGH-MAGNIFICATION SINGLE-LENS GRAVITATIONAL MICROLENSING EVENTS WITH LENSES PASSING OVER SOURCE STARS

    International Nuclear Information System (INIS)

    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-2011-BLG-274, OGLE-2011-BLG-0990/MOA-2011-BLG-300, and OGLE-2011-BLG-1101/MOA-2011-BLG-325. For all of the events, we measure the linear limb-darkening coefficients of the surface brightness profile of source stars by measuring the deviation of the light curves near the peak affected by the finite-source effect. For seven events, we measure the Einstein radii and the lens-source relative proper motions. Among them, five events are found to have Einstein radii of less than 0.2 mas, making the lenses very low mass star or brown dwarf candidates. For MOA-2011-BLG-274, especially, the small Einstein radius of θE ∼ 0.08 mas combined with the short timescale of tE ∼ 2.7 days suggests the possibility that the lens is a free-floating planet. For MOA-2009-BLG-174, we measure the lens parallax and thus uniquely determine the physical parameters of the lens. We also find that the measured lens mass of ∼0.84 M☉ is consistent with that of a star blended with the source, suggesting that the blend is likely to be the lens. Although we did not find planetary signals for any of the events, we provide exclusion diagrams showing the confidence levels excluding the existence of a planet as a function of the separation and mass ratio.

  15. CHARACTERIZING LENSES AND LENSED STARS OF HIGH-MAGNIFICATION SINGLE-LENS GRAVITATIONAL MICROLENSING EVENTS WITH LENSES PASSING OVER SOURCE STARS

    Energy Technology Data Exchange (ETDEWEB)

    Choi, J.-Y.; Shin, I.-G.; Park, S.-Y.; Han, C. [Department of Physics, Institute for Astrophysics, Chungbuk National University, Cheongju 371-763 (Korea, Republic of); Gould, A.; Gaudi, B. S.; Henderson, C. B. [Department of Astronomy, Ohio State University, 140 W. 18th Ave., Columbus, OH 43210 (United States); Sumi, T. [Department of Earth and Space Science, Osaka University, Osaka 560-0043 (Japan); Udalski, A. [Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa (Poland); Beaulieu, J.-P. [Institut d' Astrophysique de Paris, UMR7095 CNRS-Universite Pierre and Marie Curie, 98 bis boulevard Arago, 75014 Paris (France); Street, R. [Las Cumbres Observatory Global Telescope Network, 6740B Cortona Dr, Suite 102, Goleta, CA 93117 (United States); Dominik, M. [School of Physics and Astronomy, SUPA, University of St. Andrews, North Haugh, St. Andrews, KY16 9SS (United Kingdom); Allen, W. [Vintage Lane Observatory, Blenheim (New Zealand); Almeida, L. A. [Instituto Nacional de Pesquisas Espaciais/MCTI, Sao Jose dos Campos, Sao Paulo (Brazil); Bos, M. [Molehill Astronomical Observatory, North Shore (New Zealand); Christie, G. W. [Auckland Observatory, P.O. Box 24-180, Auckland (New Zealand); Depoy, D. L. [Department of Physics, Texas A and M University, College Station, TX (United States); Dong, S. [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States); Drummond, J. [Possum Observatory, Patutahi (New Zealand); Gal-Yam, A. [Benoziyo Center for Astrophysics, Weizmann Institute (Israel); Collaboration: muFUN Collaboration; MOA Collaboration; OGLE Collaboration; PLANET Collaboration; RoboNet Collaboration; MiNDSTEp Consortium; and others

    2012-05-20

    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-2011-BLG-274, OGLE-2011-BLG-0990/MOA-2011-BLG-300, and OGLE-2011-BLG-1101/MOA-2011-BLG-325. For all of the events, we measure the linear limb-darkening coefficients of the surface brightness profile of source stars by measuring the deviation of the light curves near the peak affected by the finite-source effect. For seven events, we measure the Einstein radii and the lens-source relative proper motions. Among them, five events are found to have Einstein radii of less than 0.2 mas, making the lenses very low mass star or brown dwarf candidates. For MOA-2011-BLG-274, especially, the small Einstein radius of {theta}{sub E} {approx} 0.08 mas combined with the short timescale of t{sub E} {approx} 2.7 days suggests the possibility that the lens is a free-floating planet. For MOA-2009-BLG-174, we measure the lens parallax and thus uniquely determine the physical parameters of the lens. We also find that the measured lens mass of {approx}0.84 M{sub Sun} is consistent with that of a star blended with the source, suggesting that the blend is likely to be the lens. Although we did not find planetary signals for any of the events, we provide exclusion diagrams showing the confidence levels excluding the existence of a planet as a function of the separation and mass ratio.

  16. Characterization of the CRNA Bonner sphere spectrometer based on {sup 6}LiI scintillator exposed to an {sup 241}Am-Be neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Mazrou, Hakim [Centre de Recherche Nucleaire d' Alger (CRNA), 02 Boulevard Frantz Fanon, B.P. 399, 16000 Alger (Algeria)], E-mail: mazrou_h@comena-dz.org; Sidahmed, Tassadit; Idiri, Zahir; Lounis-Mokrani, Zohra; Bedek, Said [Centre de Recherche Nucleaire d' Alger (CRNA), 02 Boulevard Frantz Fanon, B.P. 399, 16000 Alger (Algeria); Allab, Malika [Faculte de Physique, Universite des Sciences et de la Technologie Houari-Boumediene (USTHB), Alger (Algeria)

    2008-02-15

    In the present work, measurements have been performed using an available multisphere neutron spectrometer based on a calibrated {sup 6}LiI scintillation detector (10mmox2mm) exposed to an {sup 241}Am-Be neutron source. Sensitive analysis has been performed to assess influence of angle and source-detector distances dependence on the detector responses. Our experimental responses were compared with the published experimental and calculated data for two {sup 241}Am-Be (ISO, PTB) neutron spectra with (4mmox4mm) {sup 6}LiI detector. A discrepancy by a factor of about two was achieved and it is chiefly due to the difference shown in active surface of both detectors.

  17. 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.

  18. 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...

  19. Finding, Characterizing, and Classifying Variable Sources in Multi-epoch Sky Surveys: QSOs and RR Lyrae in PS1 3π data

    Science.gov (United States)

    Hernitschek, Nina; Schlafly, Edward F.; Sesar, Branimir; Rix, Hans-Walter; Hogg, David W.; Ivezić, Željko; 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.

    2016-01-01

    In area and depth, the Pan-STARRS1 (PS1) 3π survey is unique among many-epoch, multi-band surveys and has enormous potential for the 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 light curves through light curve structure functions, effectively turning PS1 into a ∼35-epoch survey. We use this approach to estimate variability amplitudes and timescales (ωr, τ) for all point sources brighter than rP1 = 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 ∼75% and completeness ∼92% can be selected. On this basis we have identified a sample of ∼1,000,000 QSO candidates, as well as an unprecedentedly large and deep sample of ∼150,000 RR Lyrae candidates with distances from ∼10 to ∼120 kpc. Within the Draco dwarf spheroidal, we demonstrate a distance precision of 6% for RR Lyrae candidates. We provide a catalog of all likely variable point sources and likely QSOs in PS1, a total of 25.8 × 106 sources.

  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.