Sample records for back-streaming electron dump

  1. RF-driven ion source with a back-streaming electron dump

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kwan, Joe; Ji, Qing

    A novel ion source is described having an improved lifetime. The ion source, in one embodiment, is a proton source, including an external RF antenna mounted to an RF window. To prevent backstreaming electrons formed in the beam column from striking the RF window, a back streaming electron dump is provided, which in one embodiment is formed of a cylindrical tube, open at one end to the ion source chamber and capped at its other end by a metal plug. The plug, maintained at the same electrical potential as the source, captures these backstreaming electrons, and thus prevents localized heatingmore » of the window, which due to said heating, might otherwise cause window damage.« less

  2. Influence of the Trojan Nickel Mine on surface water quality, Mazowe valley, Zimbabwe: Runoff chemistry and acid generation potential of waste rock

    NASA Astrophysics Data System (ADS)

    Lupankwa, Keretia; Love, David; Mapani, Benjamin; Mseka, Stephen; Meck, Maideyi

    The impacts of mining on the environment depend on the nature of the ore body, the type of mining and the size of operation. The focus of this study is on Trojan Nickel Mine which is located 90 km north of Harare, Zimbabwe. It produces nickel from iron, iron-nickel and copper-nickel sulphides and disposes of waste rock in a rock dump. Surface water samples were taken at 11 points selected from a stream which drains the rock dump, a stream carrying underground water and the river into which these streams discharge. Samples were analysed for metals using atomic absorption spectrometry, for sulphates by gravitation and for carbonates and bicarbonates by back titration. Ninteen rock samples were collected from the dump and static tests were performed using the Sobek acid base accounting method. The results show that near neutral runoff (pH 7.0-8.5) with high concentrations of sulphate (over 100 mg/L) and some metals (Pb > 1.0 mg/L and Ni > 0.2 mg/L) emanates from the dump. This suggests that acid mine drainage is buffered in the dump (probably by carbonates). This is supported by the static tests, which show that the fine fraction of dump material neutralises acid. Runoff from the dump flows into a pond. Concentrations of sulphates and metals decrease after the dump runoff enters the pond, but sufficient remains to increase levels of calcium, sulphate, bicarbonate, iron and lead in the Pote River. The drop in concentrations at the pond indicates that the settling process has a positive effect on water quality. This could be enhanced by treating the pond water to raise pH, thus precipitating out metals and decreasing their concentrations in water draining from the pond.

  3. Strong constraints on sub-GeV dark sectors from SLAC beam dump E137.

    PubMed

    Batell, Brian; Essig, Rouven; Surujon, Ze'ev

    2014-10-24

    We present new constraints on sub-GeV dark matter and dark photons from the electron beam-dump experiment E137 conducted at SLAC in 1980-1982. Dark matter interacting with electrons (e.g., via a dark photon) could have been produced in the electron-target collisions and scattered off electrons in the E137 detector, producing the striking, zero-background signature of a high-energy electromagnetic shower that points back to the beam dump. E137 probes new and significant ranges of parameter space and constrains the well-motivated possibility that dark photons that decay to light dark-sector particles can explain the ∼3.6σ discrepancy between the measured and standard model value of the muon anomalous magnetic moment. It also restricts the parameter space in which the relic density of dark matter in these models is obtained from thermal freeze-out. E137 also convincingly demonstrates that (cosmic) backgrounds can be controlled and thus serves as a powerful proof of principle for future beam-dump searches for sub-GeV dark-sector particles scattering off electrons in the detector.

  4. Mapping mine wastes and analyzing areas affected by selenium-rich water runoff in southeast Idaho using AVIRIS imagery and digital elevation data

    USGS Publications Warehouse

    Mars, J.C.; Crowley, J.K.

    2003-01-01

    Remotely sensed hyperspectral and digital elevation data from southeastern Idaho are combined in a new method to assess mine waste contamination. Waste rock from phosphorite mining in the area contains selenium, cadmium, vanadium, and other metals. Toxic concentrations of selenium have been found in plants and soils near some mine waste dumps. Eighteen mine waste dumps and five vegetation cover types in the southeast Idaho phosphate district were mapped by using Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) imagery and field data. The interaction of surface water runoff with mine waste was assessed by registering the AVIRIS results to digital elevation data, enabling determinations of (1) mine dump morphologies, (2) catchment watershed areas above each mine dump, (3) flow directions from the dumps, (4) stream gradients, and (5) the extent of downstream wetlands available for selenium absorption. Watersheds with the most severe selenium contamination, such as the South Maybe Canyon watershed, are associated with mine dumps that have large catchment watershed areas, high stream gradients, a paucity of downstream wetlands, and dump forms that tend to obstruct stream flow. Watersheds associated with low concentrations of dissolved selenium, such as Angus Creek, have mine dumps with small catchment watershed areas, low stream gradients, abundant wetlands vegetation, and less obstructing dump morphologies. ?? 2002 Elsevier Science Inc. All rights reserved.

  5. 30 CFR 77.1608 - Dumping facilities.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... weight of a loaded dump truck, trucks shall be dumped a safe distance back from the edge of the bank. (c... material. (d) Grizzlies, grates, and other sizing devices at dump and transfer points shall be anchored...

  6. Low energy and high energy dumps for ELI-NP accelerator facility: rational and Monte-Carlo calculations - results

    NASA Astrophysics Data System (ADS)

    Esposito, A.; Frasciello, O.; Pelliccioni, M.

    2017-09-01

    ELI-NP will be a new international research infrastructure facility for laser-based Nuclear Physics to be built in Magurele, south west of Bucharest, Romania. For the machine to operate as an intense γ rays' source based on Compton back-scattering, electron beams are employed, undergoing a two stage acceleration to 320 MeV and 740 MeV (and, with an eventual energy upgrade, also to 840 MeV) beam energies. In order to assess the radiation safety issues, concerning the effectiveness of the dumps in absorbing the primary electron beams, the generated prompt radiation field and the residual dose rates coming from the activation of constituent materials, as well as the shielding of the adjacent environments against both prompt and residual radiation fields, an extensive design study by means of Monte Carlo simulations with FLUKA code was performed, for both low energy 320 MeV and high energy 720 MeV (840 MeV) beam dumps. For the low energy dump we discuss also the rational of the choice to place it in the building basement, instead of installing it in one of the shielding wall at the machine level, as it was originally conceived. Ambient dose equivalent rate constraints, according to the Rumenian law in force in radiation protection matter were 0.1 /iSv/h everywhere outside the shielding walls and 1.4 μiSv/h outside the high energy dump area. The dumps' placements and layouts are shown to be fully compliant with the dose constraints and environmental impact.

  7. Geochemical characterisation of pyrite oxidation and environmental problems related to release and transport of metals from a coal washing low-grade waste dump, Shahrood, northeast Iran.

    PubMed

    Doulati Ardejani, Faramarz; Jodieri Shokri, Behshad; Moradzadeh, Ali; Shafaei, Seyed Ziadin; Kakaei, Reza

    2011-12-01

    Pyrite oxidation and release of the oxidation products from a low-grade coal waste dump to stream, groundwater and soil was investigated by geochemical and hydrogeochemical techniques at Alborz Sharghi coal washing plant, Shahrood, northeast Iran. Hydrogeochemical analysis of water samples indicates that the metal concentrations in the stream waters were low. Moreover, the pH of the water showed no considerable change. The analysis of the stream water samples shows that except the physical changes, pyrite oxidation process within the coal washing waste dump has not affected the quality of the stream water. Water type was determined to be calcium sulphate. The results of the analysis of groundwater samples indicate that the pH varies from 7.41 to 7.51. The concentrations of the toxic metals were low. The concentration of SO4 is slightly above than its standard concentration in potable water. It seems that the groundwater less affected by the coal washing operation in the study area. Geochemical analysis of the sediment samples shows that Fe concentration decreases gradually downstream the waste dump with pH rising. SO(4) decreases rapidly downstream direction. Copper, Zn and Co concentrations decrease with distance from the waste dump due to a dilution effect by the mixing of uncontaminated sediments. These elements, in particular, Zn are considerably elevated in sediment sample collected at the nearest distance to the waste dump. There is no doubt that such investigations can help to develop an appropriate water remediation plan.

  8. Assessment of nonpoint source chemical loading potential to watersheds containing uranium waste dumps associated with uranium exploration and mining, Browns Hole, Utah

    USGS Publications Warehouse

    Marston, Thomas M.; Beisner, Kimberly R.; Naftz, David L.; Snyder, Terry

    2012-01-01

    During August of 2008, 35 solid-phase samples were collected from abandoned uranium waste dumps, undisturbed geologic background sites, and adjacent streambeds in Browns Hole in southeastern Utah. The objectives of this sampling program were (1) to assess impacts on human health due to exposure to radium, uranium, and thorium during recreational activities on and around uranium waste dumps on Bureau of Land Management lands; (2) to compare concentrations of trace elements associated with mine waste dumps to natural background concentrations; (3) to assess the nonpoint source chemical loading potential to ephemeral and perennial watersheds from uranium waste dumps; and (4) to assess contamination from waste dumps to the local perennial stream water in Muleshoe Creek. Uranium waste dump samples were collected using solid-phase sampling protocols. Solid samples were digested and analyzed for major and trace elements. Analytical values for radium and uranium in digested samples were compared to multiple soil screening levels developed from annual dosage calculations in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act's minimum cleanup guidelines for uranium waste sites. Three occupancy durations for sites were considered: 4.6 days per year, 7.0 days per year, and 14.0 days per year. None of the sites exceeded the radium soil screening level of 96 picocuries per gram, corresponding to a 4.6 days per year exposure. Two sites exceeded the radium soil screening level of 66 picocuries per gram, corresponding to a 7.0 days per year exposure. Seven sites exceeded the radium soil screening level of 33 picocuries per gram, corresponding to a 14.0 days per year exposure. A perennial stream that flows next to the toe of a uranium waste dump was sampled, analyzed for major and trace elements, and compared with existing aquatic-life and drinking-water-quality standards. None of the water-quality standards were exceeded in the stream samples.

  9. Mid-infrared picosecond pump-dump-probe and pump-repump-probe experiments to resolve a ground-state intermediate in cyanobacterial phytochrome Cph1.

    PubMed

    van Wilderen, Luuk J G W; Clark, Ian P; Towrie, Michael; van Thor, Jasper J

    2009-12-24

    Multipulse picosecond mid-infrared spectroscopy has been used to study photochemical reactions of the cyanobacterial phytochrome photoreceptor Cph1. Different photophysical schemes have been discussed in the literature to describe the pathways after photoexcitation, particularly, to identify reaction phases that are linked to photoisomerisation and electronic decay in the 1566-1772 cm(-1) region that probes C=C and C=O stretching modes of the tetrapyrrole chromophore. Here, multipulse spectroscopy is employed, where, compared to conventional visible pump-mid-infrared probe spectroscopy, an additional visible pulse is incorporated that interacts with populations that are evolving on the excited- and ground-state potential energy surfaces. The time delays between the pump and the dump pulse are chosen such that the dump pulse interacts with different phases in the reaction process. The pump and dump pulses are at the same wavelength, 640 nm, and are resonant with the Pr ground state as well as with the excited state and intermediates. Because the dump pulse additionally pumps the remaining, partially recovered, and partially oriented ground-state population, theory is developed for estimating the fraction of excited-state molecules. The calculations take into account the model-dependent ground-state recovery fraction, the angular dependence of the population transfer resulting from the finite bleach that occurs with linearly polarized intense femtosecond optical excitation, and the partially oriented population for the dump field. Distinct differences between the results from the experiments that use a 1 or a 14 ps dump time favor a branching evolution from S1 to an excited state or reconfigured chromophore and to a newly identified ground-state intermediate (GSI). Optical dumping at 1 ps shows the instantaneous induced absorption of a delocalized C=C stretching mode at 1608 cm(-1), where the increased cross section is associated with the electronic ground-state structure of the ZZZ configuration of the linear tetrapyrrole chromophore. The dump-induced absorption decays with time constants of 5 and 19 ps to the Pr ground state. Employing a dump pulse at 14 ps results in an instantaneous decrease of the absorption of the 1608 cm(-1) band, indicating repumping of the GSI. The dump-induced absorption recovers back to the GSI with a 6 ps lifetime. A spectral similarity is observed between the 6 ps phase in the dump experiment and the 3 ps component found in the two-pulse pump-probe measurement. Combined with the dominance of ground-state absorption bands in the dump-induced spectrum, this indicates the presence of a GSI, which is additionally characterized by previously unidentified induced absorption at 1710 and 1570-80 cm(-1). The metastable photoproduct Lumi-R, which is in the electronic ground state and populated at 500 ps after excitation of Pr, is highly efficiently repumped into the Pr ground state with the power density used. After repumping, Lumi-R is not recovered on the 500 ps time scale of the experiment and is distinct from the GSI of Pr since it is not associated with its characteristic induced absorption at 1710 and 1570-80 cm(-1).

  10. The design of the electron beam dump unit of Turkish Accelerator Center (TAC)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cite, L. H., E-mail: hcite@gantep.edu.tr; Yilmaz, M., E-mail: Mustafa.Yilmaz@gaziantep.edu.tr

    The required simulations of the electron beam interactions for the design of electron beam dump unit for an accelerator which will operate to get two Infra-Red Free Electron Lasers (IR-FEL) covering the range of 3-250 microns is presented in this work. Simulations have been carried out to understand the interactions of a bulk of specially shaped of four different and widely used materials for the dump materials for a 77 pC, 40 MeV, 13 MHz repetition rate e-beam. In the simulation studies dump materials are chosen to absorb the 99% of the beam energy and to restrict the radio-isotope production in themore » bulk of the dump. A Lead shielding also designed around the dump core to prevent the leakage out of the all the emitted secondary radiations, e.g., neutrons, photons. The necessary dump material requirements, for the overall design considerations and the possible radiation originated effects on the dump unit, are discussed and presented.« less

  11. The expansion of polarization charge layers into magnetized vacuum - Theory and computer simulations

    NASA Technical Reports Server (NTRS)

    Galvez, Miguel; Borovsky, Joseph E.

    1991-01-01

    The formation and evolution of polarization charge layers on cylindrical plasma streams moving in vacuum are investigated using analytic theory and 2D electrostatic particle-in-cell computer simulations. It is shown that the behavior of the electron charge layer goes through three stages. An early time expansion is driven by electrostatic repulsion of electrons in the charge layer. At the intermediate stage, the simulations show that the electron-charge-layer expansion is halted by the positively charged plasma stream. Electrons close to the stream are pulled back to the stream and a second electron expansion follows in time. At the late stage, the expansion of the ion charge layer along the magnetic field lines accompanies the electron expansion to form an ambipolar expansion. It is found that the velocities of these electron-ion expansions greatly exceed the velocities of ambipolar expansions which are driven by plasma temperatures.

  12. Reaction pathways of photoexcited retinal in proteorhodopsin studied by pump-dump-probe spectroscopy.

    PubMed

    Rupenyan, Alisa; van Stokkum, Ivo H M; Arents, Jos C; van Grondelle, Rienk; Hellingwerf, Klaas J; Groot, Marie Louise

    2009-12-17

    Proteorhodopsin (pR) is a membrane-embedded proton pump from the microbial rhodopsin family. Light absorption by its retinal chromophore initiates a photocycle, driven by trans/cis isomerization on the femtosecond to picosecond time scales. Here, we report a study on the photoisomerization dynamics of the retinal chromophore of pR, using dispersed ultrafast pump-dump-probe spectroscopy. The application of a pump pulse initiates the photocycle, and with an appropriately tuned dump pulse applied at a time delay after the dump, the molecules in the initial stages of the photochemical process can be de-excited and driven back to the ground state. In this way, we were able to resolve an intermediate on the electronic ground state that represents chromophores that are unsuccessful in isomerization. In particular, the fractions of molecules that undergo slow isomerization (20 ps) have a high probability to enter this state rather than the isomerized K-state. On the ground state reaction surface, return to the stable ground state conformation via a structural or vibrational relaxation occurs in 2-3 ps. Inclusion of this intermediate in the kinetic scheme led to more consistent spectra of the retinal-excited state, and to a more accurate estimation of the quantum yield of isomerization (Phi = 0.4 at pH 6).

  13. Radionuclides and toxic elements transfer from the princess dump to water in Roodepoort, South Africa.

    PubMed

    Dlamini, S G; Mathuthu, M M; Tshivhase, V M

    2016-03-01

    High concentrations of radionuclides and toxic elements in gold mine tailings facilities present a health hazard to the environment and people living near that area. Soil and water samples from selected areas around the Princess Mine dump were collected. Soil sampling was done on the surface (15 cm) and also 100 cm below the surface. Water samples were taken from near the dump, mid-stream and the flowing part of the stream (drainage pipe) passing through Roodepoort from the mine dump. Soil samples were analyzed by gamma-ray spectroscopy using a HPGe detector to determine the activity concentrations of (238)U, (232)Th and (4) (​40)K from the activities of the daughter nuclides in the respective decay chains. The average activity concentrations for uranium and thorium in soil were calculated to be 129 ± 36.1 Bq/kg and 18.1 ± 4.01 Bq/kg, respectively. Water samples were analyzed using Inductively Coupled Plasma Mass Spectrometer. Transfer factors for uranium and thorium from soil to water (at point A closest to dump) were calculated to be 0.494 and 0.039, respectively. At point Z2, which is furthest from the dump, they were calculated to be 0.121 and 0.004, respectively. These transfer factors indicate that there is less translocation of the radionuclides as the water flows. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Range imaging laser radar

    DOEpatents

    Scott, Marion W.

    1990-01-01

    A laser source is operated continuously and modulated periodically (typicy sinusoidally). A receiver imposes another periodic modulation on the received optical signal, the modulated signal being detected by an array of detectors of the integrating type. Range to the target determined by measuring the phase shift of the intensity modulation on the received optical beam relative to a reference. The receiver comprises a photoemitter for converting the reflected, periodically modulated, return beam to an accordingly modulated electron stream. The electron stream is modulated by a local demodulation signal source and subsequently converted back to a photon stream by a detector. A charge coupled device (CCD) array then averages and samples the photon stream to provide an electrical signal in accordance with the photon stream.

  15. Range imaging laser radar

    DOEpatents

    Scott, M.W.

    1990-06-19

    A laser source is operated continuously and modulated periodically (typically sinusoidally). A receiver imposes another periodic modulation on the received optical signal, the modulated signal being detected by an array of detectors of the integrating type. Range to the target determined by measuring the phase shift of the intensity modulation on the received optical beam relative to a reference. The receiver comprises a photoemitter for converting the reflected, periodically modulated, return beam to an accordingly modulated electron stream. The electron stream is modulated by a local demodulation signal source and subsequently converted back to a photon stream by a detector. A charge coupled device (CCD) array then averages and samples the photon stream to provide an electrical signal in accordance with the photon stream. 2 figs.

  16. Following an electron bunch for free electron laser

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2012-01-01

    A video artist's ultra-slow-motion impression of an APEX-style electron gun firing a continuous train of electron bunches into a superconducting linear accelerator (in reality this would happen a million times a second). As they approach the speed of light the bunches contract, maintaining beam quality. After acceleration, the electron bunches are diverted into one or more undulators, the key components of free electron lasers. Oscillating back and forth in the changing magnetic field, they create beams of structured x-ray pulses. Before entering the experimental areas the electron bunches are diverted to a beam dump. (Animation created by Illumina Visual, http://www.illuminavisual.com/,more » for Lawrence Berkeley National Laboratory. Music for this excerpt, "Feeling Dark (Behind The Mask)" is by 7OOP3D http://ccmixter.org/files/7OOP3D/29126 and is licensed under a Creative Commons license: http://creativecommons.org/licenses/by-nc/3.0/)« less

  17. VLBI2010 Receiver Back End Comparison

    NASA Technical Reports Server (NTRS)

    Petrachenko, Bill

    2013-01-01

    VLBI2010 requires a receiver back-end to convert analog RF signals from the receiver front end into channelized digital data streams to be recorded or transmitted electronically. The back end functions are typically performed in two steps: conversion of analog RF inputs into IF bands (see Table 2), and conversion of IF bands into channelized digital data streams (see Tables 1a, 1b and 1c). The latter IF systems are now completely digital and generically referred to as digital back ends (DBEs). In Table 2 two RF conversion systems are compared, and in Tables 1a, 1b, and 1c nine DBE systems are compared. Since DBE designs are advancing rapidly, the data in these tables are only guaranteed to be current near the update date of this document.

  18. Crayfish use of trash versus natural cover in incised, sand-bed streams

    Treesearch

    Susan B. Adams

    2014-01-01

    Historic land use changes and subsequent river channelization created deeply incised, unstable stream channels largely devoid of natural cover throughout the Yazoo River basin, Mississippi, USA. Large trash (e.g., televisions, toilets, car parts) dumped in streams provided shelter for some aquatic fauna. To determine whether trash served as a surrogate for natural...

  19. Ultrafast dynamics of photoactive yellow protein via the photoexcitation and emission processes.

    PubMed

    Nakamura, Ryosuke; Hamada, Norio; Ichida, Hideki; Tokunaga, Fumio; Kanematsu, Yasuo

    2007-01-01

    Pump-dump fluorescence spectroscopy was performed for photoactive yellow protein (PYP) at room temperature. The effect of the dump pulse on the population of the potential energy surface of the electronic excited state was examined as depletion in the stationary fluorescence intensity. The dynamic behavior of the population in the electronic excited state was successfully probed in the various combinations of the pump-dump delay, the dump-pulse wavelength, the dump-pulse energy and the observation wavelength. The experimental results were compared with the results obtained by the femtosecond time-resolved fluorescence spectroscopy.

  20. An evaluation of problems arising from acid mine drainage in the vicinity of Shasta Lake, Shasta County, California

    USGS Publications Warehouse

    Fuller, Richard H.; Shay, J.M.; Ferreira, R.F.; Hoffman, R.J.

    1978-01-01

    Streams draining the mined areas of massive sulfide ore deposits in the Shasta Mining Districts of northern California are generally acidic and contain large concentrations of dissolved metals, including iron, copper, and zinc. The streams, including Flat, Little Backbone, Spring, West Squaw, Horse, and Zinc Creeks, discharge into Shasta Reservoir and the Sacramento River and have caused numerous fish kills. The sources of pollution are discharge from underground mines, streams that flow into open pits, and streams that flow through pyritic mine dumps where the oxidation of pyrite and other sulfide minerals results in the production of acid and the mobilization of metals. Suggested methods of treatment include the use of air and hydraulic seals in the mines, lime neutralization of mine effluent, channeling of runoff and mine effluent away from mine and tailing areas, and the grading and sealing of mine dumps. A comprehensive preabatement and postabatement program is recommended to evaluate the effects of any treatment method used. (Woodard-USGS)

  1. Molecular alignment effect on the photoassociation process via a pump-dump scheme.

    PubMed

    Wang, Bin-Bin; Han, Yong-Chang; Cong, Shu-Lin

    2015-09-07

    The photoassociation processes via the pump-dump scheme for the heternuclear (Na + H → NaH) and the homonuclear (Na + Na → Na2) molecular systems are studied, respectively, using the time-dependent quantum wavepacket method. For both systems, the initial atom pair in the continuum of the ground electronic state (X(1)Σ(+)) is associated into the molecule in the bound states of the excited state (A(1)Σ(+)) by the pump pulse. Then driven by a time-delayed dumping pulse, the prepared excited-state molecule can be transferred to the bound states of the ground electronic state. It is found that the pump process can induce a superposition of the rovibrational levels |v, j〉 on the excited state, which can lead to the field-free alignment of the excited-state molecule. The molecular alignment can affect the dumping process by varying the effective coupling intensity between the two electronic states or by varying the population transfer pathways. As a result, the final population transferred to the bound states of the ground electronic state varies periodically with the delay time of the dumping pulse.

  2. Molecular alignment effect on the photoassociation process via a pump-dump scheme

    NASA Astrophysics Data System (ADS)

    Wang, Bin-Bin; Han, Yong-Chang; Cong, Shu-Lin

    2015-09-01

    The photoassociation processes via the pump-dump scheme for the heternuclear (Na + H → NaH) and the homonuclear (Na + Na → Na2) molecular systems are studied, respectively, using the time-dependent quantum wavepacket method. For both systems, the initial atom pair in the continuum of the ground electronic state (X1Σ+) is associated into the molecule in the bound states of the excited state (A1Σ+) by the pump pulse. Then driven by a time-delayed dumping pulse, the prepared excited-state molecule can be transferred to the bound states of the ground electronic state. It is found that the pump process can induce a superposition of the rovibrational levels |v, j> on the excited state, which can lead to the field-free alignment of the excited-state molecule. The molecular alignment can affect the dumping process by varying the effective coupling intensity between the two electronic states or by varying the population transfer pathways. As a result, the final population transferred to the bound states of the ground electronic state varies periodically with the delay time of the dumping pulse.

  3. 30. HULETT NO. 2 IN MOTION; OPERATOR HAS JUST DUMPED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. HULETT NO. 2 IN MOTION; OPERATOR HAS JUST DUMPED A GRAB BUCKET OF ORE INTO THE RECEIVING HOPPER AND IS READY TO RETURN FOR ANOTHER LOAD. A ROUND TRIP FROM THE BOAT TO THE HOPPER AND BACK CAN BE MADE IN 50 SECONDS. - Pennsylvania Railway Ore Dock, Lake Erie at Whiskey Island, approximately 1.5 miles west of Public Square, Cleveland, Cuyahoga County, OH

  4. Reducing Backups by Utilizing DMF

    NASA Technical Reports Server (NTRS)

    Cardo, Nicholas P.; Woodrow, Thomas (Technical Monitor)

    1994-01-01

    Although a filesystem may be migratable, for a period of time the data blocks are on disk only. When performing system dumps, these data blocks are backed up to tape. If the data blocks are offline or dual resident, then only the inode is backed up. If all online files are made dual resident prior to performing system dumps, the dump time and the amount of resources required can be significantly reduced. The High Speed Processors group at the Numerical Aerodynamics Simulation (NAS) Facility at NASA Ames Research Center developed a tool to make all online files dual resident. The result is that a file whose data blocks are on DMF tape and still assigned to the original inode. Our 150GB filesystem used to take 8 to 12 hours to backup and used 50 to 60 tapes. Now the backup is typically under 10 tapes and completes in under 2 hours. This paper discusses this new tool and advantages gained by using it.

  5. An overview of the value of parabolic dish solar thermal systems in industrial cogeneration applications

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The essential elements of the cogeneration system configuration to be captured were the displacement of thermal energy by collection and use of the Brayton exhaust stream, and the sale back to the utility of any electricity production in excess of on-site requirements. In contrast to simply dumping these energy flows, their use or sale obviously serves, by itself, to increase gross value of the solar thermal energy system. Net allowable cost of the parabolic dish modules may or may not be increased, however. A consideration is that the waste heat capture and delivery subsystems are not free. This study does not address the incremental cost of adding waste heat capture, transport, and conversion (to steam, if necessary). It does compute a value for the thermal energy thereby displaced. This value can serve as a first-round input to any detailed economic evaluation of waste heat recovery.

  6. Laser pulse control of ultrafast heterogeneous electron transfer: a computational study.

    PubMed

    Wang, Luxia; May, Volkhard

    2004-10-22

    Laser pulse control of the photoinduced 90 fs charge injection from perylene into the conduction band of TiO2 is studied theoretically. The approach accounts for the electronic-ground state of the dye, the first excited state, the ionized state formed after charge injection, and the continuum of the electronic states in the conduction band, all defined vs a single reaction coordinate. To address different control tasks optimal control theory is combined with a full quantum dynamical description of the electron-vibrational motion accompanying the charge injection process. First it is proved in which way the charge injection time can be changed by tailored laser pulses. In a second step a pump-dump scheme from the perylene ground state to the first excited electronic state and back to the ground state is discussed. Because of the strong coupling of the excited perylene state to the band continuum of TiO2 this control task is more suited to an experimental test than the direct control of the charge injection.

  7. Molecular alignment effect on the photoassociation process via a pump-dump scheme

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Bin-Bin; Han, Yong-Chang, E-mail: ychan@dlut.edu.cn; Cong, Shu-Lin

    The photoassociation processes via the pump-dump scheme for the heternuclear (Na + H → NaH) and the homonuclear (Na + Na → Na{sub 2}) molecular systems are studied, respectively, using the time-dependent quantum wavepacket method. For both systems, the initial atom pair in the continuum of the ground electronic state (X{sup 1}Σ{sup +}) is associated into the molecule in the bound states of the excited state (A{sup 1}Σ{sup +}) by the pump pulse. Then driven by a time-delayed dumping pulse, the prepared excited-state molecule can be transferred to the bound states of the ground electronic state. It is found thatmore » the pump process can induce a superposition of the rovibrational levels |v, j〉 on the excited state, which can lead to the field-free alignment of the excited-state molecule. The molecular alignment can affect the dumping process by varying the effective coupling intensity between the two electronic states or by varying the population transfer pathways. As a result, the final population transferred to the bound states of the ground electronic state varies periodically with the delay time of the dumping pulse.« less

  8. Mössbauer, TEM/SAED and XRD investigation on waste dumps of the Valea lui Stan gold mines

    NASA Astrophysics Data System (ADS)

    Constantinescu, Serban Grigore; Udubasa, Sorin S.; Udubasa, Gheorghe; Kuncser, Victor; Popescu-Pogrion, Nicoleta; Mercioniu, Ionel; Feder, Marcel

    2012-03-01

    The complementary investigation techniques, Mössbauer spectroscopy, transmission electron microscopy with selected area electron diffraction (TEM/SAED), X-ray diffraction (XRD) have been used to investigate the fate of the Valea lui Stan, Romania, gold-ore nanoscale-minerals during the long time of residence in the waste dumps. The preliminary investigations showed such waste dumps to contain significant amount of metals which cannot be identified by conventional methods. An intense research activity started up in order to evaluate the possibilities to recycle Valea lui Stan waste dumps and to recover metals by chemical or phytoextraction procedures. The waste dumps naturally show different mineral constituents with clay minerals as major phases, observed by XRD-technique. Although the waste dumps materials have whitish-yellowish colours, MÖSSBAUER technique evidences the presence of the finely dispersed iron bearing minerals. The authors are focusing to inspect and analyze Fe-compounds in the samples collected from Valea lui Stan's waste dumps in order to identify the magnetic phases by Mössbauer technique.

  9. Quench protection analysis of the Mu2e production solenoid

    NASA Astrophysics Data System (ADS)

    Kashikhin, Vadim; Ambrosio, Giorgio; Andreev, Nikolai; Lamm, Michael; Nicol, Thomas; Orris, Darryl; Page, Thomas

    2014-01-01

    The Muon-to-Electron conversion experiment (Mu2e), under development at Fermilab, seeks to detect direct muon to electron conversion to provide evidence for a process violating muon and electron lepton number conservation that cannot be explained by the Standard Model of particle physics. The Mu2e magnet system consists of three large superconducting solenoids. In case of a quench, the stored magnetic energy is extracted to an external dump circuit. However, because of the fast current decay, a significant fraction of the energy dissipates inside of the cryostat in the coil support shells made of structural aluminum, and in the radiation shield. A 3D finite-element model of the complete cold-mass was created in order to simulate the quench development and understand the role of the quench-back. The simulation results are reported at the normal and non-standard operating conditions.

  10. Quench protection analysis of the Mu2e production solenoid

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kashikhin, Vadim; Ambrosio, Giorgio; Andreev, Nikolai

    The Muon-to-Electron conversion experiment (Mu2e), under development at Fermilab, seeks to detect direct muon to electron conversion to provide evidence for a process violating muon and electron lepton number conservation that cannot be explained by the Standard Model of particle physics. The Mu2e magnet system consists of three large superconducting solenoids. In case of a quench, the stored magnetic energy is extracted to an external dump circuit. However, because of the fast current decay, a significant fraction of the energy dissipates inside of the cryostat in the coil support shells made of structural aluminum, and in the radiation shield. Amore » 3D finite-element model of the complete cold-mass was created in order to simulate the quench development and understand the role of the quench-back. The simulation results are reported at the normal and non-standard operating conditions.« less

  11. Soil contamination by brominated flame retardants in open waste dumping sites in Asian developing countries.

    PubMed

    Eguchi, Akifimi; Isobe, Tomohiko; Ramu, Karri; Tue, Nguyen Minh; Sudaryanto, Agus; Devanathan, Gnanasekaran; Viet, Pham Hung; Tana, Rouch Seang; Takahashi, Shin; Subramanian, Annamalai; Tanabe, Shinsuke

    2013-03-01

    In Asian developing countries, large amounts of municipal wastes are dumped into open dumping sites each day without adequate management. This practice may cause several adverse environmental consequences and increase health risks to local communities. These dumping sites are contaminated with many chemicals including brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs). BFRs may be released into the environment through production processes and through the disposal of plastics and electronic wastes that contain them. The purpose of this study was to elucidate the status of BFR pollution in municipal waste dumping sites in Asian developing countries. Soil samples were collected from six open waste dumping sites and five reference sites in Cambodia, India, Indonesia, Malaysia, and Vietnam from 1999 to 2007. The results suggest that PBDEs are the dominant contaminants in the dumping sites in Asian developing countries, whereas HBCD contamination remains low. Concentrations of PBDEs and HBCDs ranged from ND to 180 μg/kg dry wt and ND to 1.4 μg/kg dry wt, respectively, in the reference sites and from 0.20 to 430 μg/kg dry wt and ND to 2.5 μg/kg dry wt, respectively, in the dumping sites. Contamination levels of PBDEs in Asian municipal dumping sites were comparable with those reported from electronic waste dismantling areas in Pearl River delta, China. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Mobilization and attenuation of metals downstream from a base-metal mining site in the Matra Mountains, northeastern Hungary

    USGS Publications Warehouse

    Odor, L.; Wanty, R.B.; Horvath, I.; Fugedi, U.; ,

    1999-01-01

    Regional geochemical baseline values have been established for Hungary by the use of low-density stream-sediment surveys of flood-plain deposits of large drainage basins and of the fine fraction of stream sediments. The baseline values and anomaly thresholds thus produced helped to evaluate the importance of high toxic element concentrations found in soils in a valley downstream of a polymetallic vein-type base-metal mine. Erosion of the mine dumps and flotation dump, losses of metals during filtering, storage and transportation, human neglects, and operational breakdowns, have all contributed to the contamination of a small catchment basin in a procession of releases of solid waste. The sulfide-rich waste material weathers to a yellow color; this layer of 'yellow sand' blankets a narrow strip of the floodplain of Toka Creek in the valley near the town of Gyongyosoroszi. Contamination was spread out in the valley by floods. Metals present in the yellow sand include Pb, As, Cd, Cu, Zn, and Sb. Exposure of the local population to these metals may occur through inhalation of airborne particulates or by ingestion of these metals that are taken up by crops grown in the valley. To evaluate the areal extent and depth of the contamination, active stream sediment, flood-plain deposits, lake or reservoir sediments, soils, and surface water were sampled along the erosion pathways downstream of the mine and dumps. The flood-plain profile was sampled in detail to see the vertical distribution of elements and to relate the metal concentrations to the sedimentation and contamination histories of the flood plain. Downward migration of mobile Zn and Cd from the contaminated upper layers under supergene conditions is observed, while vertical migration of Pb, As, Hg and Sb appears to be insignificant. Soil profiles of 137Cs which originated from above-ground atomic bomb tests and the Chernobyl accident, provide good evidence that the upper 30-40 cm of the flood-plain sections, which includes the yellow sand contamination, were deposited in the last 30-40 years.The regional geochemical baseline values are established for Hungary using low-density stream-sediment surveys of flood-plain deposits of large drainage basins and of the fine fraction of stream sediments. The baseline values and anomaly thresholds allowed the evaluation of the importance of high toxic element concentrations in soils in a valley, downstream of a polymetallic vein-type base-metal mine. The metals present in the yellow sand include Pb, As, Cd, Cu, Zn and Sb. To evaluate the areal extent and depth of the contamination, active stream sediment, flood-plain deposits, lake or reservoir sediments, the soils and surface water were sampled along the erosion pathways downstream of the mine and dumps.

  13. Developing an Ecological Passport for an Open-Pit Dump Truck to Reduce Negative Effect on Environment

    NASA Astrophysics Data System (ADS)

    Koptev, V. Yu; Kopteva, A. V.

    2017-05-01

    Expanding the open-pit dump truck usage areas and the need to transport more and more minerals results in producing more and more powerful open-pit dump trucks, and this all is about environmental problems and potential health risks for the personnel. Harmful gas concentrations in working areas became threatening enough to have the work in some areas completely halted, until the contents of harmful substances in the air, as well as visibility on the roads, get back to norm. The article represents the new methodology for assessing comparatively the efficiency of modern transportation systems with performance and ecology characteristics taken into account, by developing an ecological passport for machines, facilitating design improvements and reducing pollution during operation.

  14. Contaminant dispersion at the rehabilitated Mary Kathleen uranium mine, Australia

    NASA Astrophysics Data System (ADS)

    Lottermoser, B. G.; Ashley, P. M.; Costelloe, M. T.

    2005-09-01

    This study reports on the transfer of contaminants from waste rock dumps and mineralised ground into soils, sediments, waters and plants at the rehabilitated Mary Kathleen uranium mine in semi-arid northwest Queensland. Numerous waste rock dumps were partly covered with benign soil and the open pit mine was allowed to flood. The mineralised and waste calc-silicate rock in the open pit and dumps has major (>1 wt%) Ca, Fe and Mg, minor (>1,000 ppm) Ce, La, Mn, P and S, subminor (>100 ppm) Ba, Cu, Th and U, and trace (<100 ppm) As, Ni, Pb, Y and Zn values. Consequently, chemical and physical weathering processes have acted on waste rock and on rock faces within the open pit, mobilising many elements and leading to their dispersion into soils, stream sediments, pit water and several plant species. Chemical dispersion is initiated by sulfide mineral breakdown, generation of sulfuric acid and formation of several soluble, transient sulfate minerals as evaporative efflorescent precipitates. Radiation doses associated with the open pit average 5.65 mSv year-1; waste dumps commonly have lower values, especially where soil-covered. Surface pit water is slightly acid, with high sulfate values accompanied by levels of U, Cu and Ni close to or above Australian water guideline values for livestock. Dispersion of U and related elements into soils and stream sediments occurs by physical (erosional) processes and from chemical precipitation. Plants growing in the mine void, on waste dumps and contaminated soil display evidence of biological uptake of U, LREE, Cu and Th and to a lesser degree of As, Ni, Pb, Y and Zn, with values being up to 1-2 orders of magnitude above background sites for the same species. Although rehabilitation procedures have been partly successful in reducing dispersion of U and related elements into the surrounding environment, it is apparent that 20 years after rehabilitation, there is significant physical and chemical mobility, including transfer into plants.

  15. Design of An 18 MW Beam Dump for 500 GeV Electron/Positron Beams at An ILC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Amann, John; /SLAC; Arnold, Ray

    This article presents a report on the progress made in designing 18 MW water based Beam Dumps for electrons or positrons for an International Linear Collider (ILC). Multi-dimensional technology issues have to be addressed for the successful design of the Beam Dump. They include calculations of power deposition by the high energy electron/positron beam bunch trains, computational fluid dynamic analysis of turbulent water flow, mechanical design, process flow analysis, hydrogen/oxygen recombiners, handling of radioactive 7Be and 3H, design of auxiliary equipment, provisions for accident scenarios, remote window exchanger, radiation shielding, etc. The progress made to date is summarized, the currentmore » status, and also the issues still to be addressed.« less

  16. Air-electron stream interactions during magnetic resonance IGRT : Skin irradiation outside the treatment field during accelerated partial breast irradiation.

    PubMed

    Park, Jong Min; Shin, Kyung Hwan; Kim, Jung-In; Park, So-Yeon; Jeon, Seung Hyuck; Choi, Noorie; Kim, Jin Ho; Wu, Hong-Gyun

    2018-01-01

    To investigate and to prevent irradiation outside the treatment field caused by an electron stream in the air generated by the magnetic field during magnetic resonance image-guided accelerated partial breast irradiation (APBI). In all, 20 patients who received APBI with a magnetic resonance image-guided radiation therapy (MR-IGRT) system were prospectively studied. The prescription dose was 38.5 Gy in 10 fractions of 3.85 Gy and delivered with a tri-cobalt system (the ViewRay system). For each patient, primary plans were delivered for the first five fractions and modified plans with different gantry angles from those of the primary plan (in-treatment plans) were delivered for the remaining five fractions to reduce the skin dose. A 1 cm thick bolus was placed in front of the patient's jaw, ipsilateral shoulder, and arm to shield them from the electron stream. Radiochromic EBT3 films were attached to the front (towards the breast) and back (towards the head) of the bolus during treatment. Correlations between the measured values and the tumor locations, treatment times, and tumor sizes were investigated. For a single fraction delivery, the average areas of the measured isodoses of 14% (0.54 Gy), 12% (0.46 Gy), and 10% (0.39 Gy) at the front of the boluses were as large as 3, 10.4, and 21.4 cm 2 , respectively, whereas no significant dose could be measured at the back of the boluses. Statistically significant but weak correlations were observed between the measured values and the treatment times. During radiotherapy for breast cancer with an MR-IGRT system, the patient must be shielded from electron streams in the air generated by the interaction of the magnetic field with the beams of the three-cobalt treatment unit to avoid unwanted irradiation of the skin outside the treatment field.

  17. Weight-of-evidence environmental risk assessment of dumped chemical weapons after WWII along the Nord-Stream gas pipeline in the Bornholm Deep.

    PubMed

    Sanderson, Hans; Fauser, Patrik; Thomsen, Marianne; Larsen, Jørn Bo

    2012-05-15

    In connection with installation of two natural gas pipelines through the Baltic Sea between Russia and Germany, there has been concern regarding potential re-suspension of historically dumped chemical warfare agents (CWA) in a nearby dump site and the potential environmental risks associated. 192 sediment and 11 porewater samples were analyzed for CWA residues, both parent and metabolites in 2008 and 2010 along the pipeline corridor next to the dump site. Macrozoobenthos and background variables were also collected and compared to the observed CWA levels and predicted potential risks. Detection frequencies and levels of intact CWA found were low, whereas CWA metabolites were more frequently found. Re-suspension of CWA residue-containing sediment from installation of the pipelines contributes marginally to the overall background CWA residue exposure and risk along the pipeline route. The multivariate weight-of-evidence analysis showed that physical and background parameters of the sediment were of higher importance for the biota than observed CWA levels. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. The mineral treasure that almost got away: Re-evaluating yesterday's mine waste

    NASA Astrophysics Data System (ADS)

    Högdahl, K.; Jonsson, E.; Troll, V.; Majka, J.

    2012-04-01

    Rare metals and semi-metals such as In, Ga, Se, Te and rare earth elements (REE) are increasing in demand for use in "new" and "green" technology. Yet, before the end of the 20th century the applications and thus the markets for these elements were limited. In many mines, the exploration paradigms and current knowledge as well as contemporary analytical methodology likely resulted in minerals hosting these metals to end up as waste, that is, on the mine dumps. In other cases, they were identified, but considered as mineralogical "exotica". Even extremely well-known and traditionally valuable metals such as gold went undetected on the dumps in some mine fields. This is due to a combination of factors such as that the deposits were "of the wrong type", assays were expensive, and suitable laboratory capacity sparse. This implies that in many regions, this old mine waste is a potential resource for several sought-after metals and semi-metals, including the ones increasingly used in modern high-tech applications. Admittedly, many older dumps and dump fields host only minor to moderate total amounts of material, but in todaýs society - increasingly focused on sustainability and related needs for recycling - this is likely to become an asset. In Sweden, many mine dumps date back hundreds of years or more as mining has been documented to go back at least 1000 years. Before the 20th century, only a single or, at best, a couple of metals were extracted from any given mine. Due to modern development in analytical techniques, the concentrations of trace elements, including highly sought-after metals and semi-metals can be obtained at moderate costs today. The presence of variable amounts of precious and rare elements along with the main ore commodity has now been documented in several cases. A recently started project in the classic, Palaeoproterozoic Bergslagen ore province in central Sweden is aimed at resolving the potential for finding and utilising these "unknown treasures". A conservative estimate based on SGU databases is that in this province alone, there are over 6500 mineralisations/deposits. A majority of these have associated mine dumps and in the case of more recently mined deposits, different types of tailings. Initial results highlight the high average contents of REÉs and identify their mineralogical and textural distribution in apatite-iron oxide ore present in both dumps and tailings. In addition, we report the occurrence of previously undetected mineralisation of indium and tungsten in different mine dumps in the western part of the province.

  19. Hazardous E-waste and its impact on soil structure

    NASA Astrophysics Data System (ADS)

    Dharini, K.; Cynthia, J. Bernadette; Kamalambikai, B.; Sudar Celestina, J. P. Arul; Muthu, D.

    2017-07-01

    E-waste disposal has been a significant issue over the past few decades with the development of technology and the plethora of electronic products produced. The inclusive term E-Waste encapsulates various forms of electrical and electronical equipment which provides no value to the current owners and it is one among the fastest growing waste streams. E-Waste is a complex, non-biodegradable waste which is generally dumped in mountain like heaps. These wastes are said to have a large quantities of lead, cadmium, arsenic etc.it is mandatory to dispose such scrupulously since they have the ability to affect the soil and water parameters. Solid waste management is a blooming field which strives to reduce the accumulation of used electronic gadgets. Rainwater gets infiltrated through the e-waste landfill and it leaches through the soil which in turn reaches the groundwater directly thereby affecting the water intended for drinking and domestic purposes. This study focuses on the consequences of toxic waste by comparing the difference in properties of the soil structure prior to and after the e-waste landfill at various concentrations.

  20. Unraveling the Primary Isomerization Dynamics in Cyanobacterial Phytochrome Cph1 with Multi-pulse Manipulations.

    PubMed

    Kim, Peter W; Rockwell, Nathan C; Freer, Lucy H; Chang, Che-Wei; Martin, Shelley S; Lagarias, J Clark; Larsen, Delmar S

    2013-07-20

    The ultrafast mechanisms underlying the initial photoisomerization (P r → Lumi-R) in the forward reaction of the cyanobacterial photoreceptor Cph1 were explored with multipulse pump-dump-probe transient spectroscopy. A recently postulated multi-population model was used to fit the transient pump-dump-probe and dump-induced depletion signals. We observed dump-induced depletion of the Lumi-R photoproduct, demonstrating that photoisomerization occurs via evolution on both the excited- and ground-state electronic surfaces. Excited-state equilibrium was not observed, as shown via the absence of a dump-induced excited-state "Le Châtelier redistribution" of excited-state populations. The importance of incorporating the inhomogeneous dynamics of Cph1 in interpreting measured transient data is discussed.

  1. Unraveling the Primary Isomerization Dynamics in Cyanobacterial Phytochrome Cph1 with Multi-pulse Manipulations

    PubMed Central

    Kim, Peter W.; Rockwell, Nathan C.; Freer, Lucy H.; Chang, Che-Wei; Martin, Shelley S.; Lagarias, J. Clark; Larsen, Delmar S.

    2013-01-01

    The ultrafast mechanisms underlying the initial photoisomerization (Pr → Lumi-R) in the forward reaction of the cyanobacterial photoreceptor Cph1 were explored with multipulse pump-dump-probe transient spectroscopy. A recently postulated multi-population model was used to fit the transient pump-dump-probe and dump-induced depletion signals. We observed dump-induced depletion of the Lumi-R photoproduct, demonstrating that photoisomerization occurs via evolution on both the excited- and ground-state electronic surfaces. Excited-state equilibrium was not observed, as shown via the absence of a dump-induced excited-state “Le Châtelier redistribution” of excited-state populations. The importance of incorporating the inhomogeneous dynamics of Cph1 in interpreting measured transient data is discussed. PMID:24143267

  2. Geochemical investigations and interim recommendations for priority abandoned mine sites on U.S.D.A. Forest Service lands, Mineral Creek watershed, San Juan County, Colorado

    USGS Publications Warehouse

    Nash, J.T.

    1999-01-01

    Field observations, sampling of mine dumps and mine drainage waters, and laboratory studies of dump materials have been made at mining areas deemed to be on public lands administered by the USDA Forest Service in the Mineral Creek watershed. Results of chemical analyses of dump materials, leachates of those materials, and of surface waters draining mines or dumps provide indications of where acid is generated or consumed, and what metals are mobilized below mines or dumps. Information on 25 sites is reviewed and reclamation priorities are ranked into four classes (high, medium, low priority, or no work required). The western side of the upper Animas watershed (the Mineral Creek watershed) has a history of mining and prospecting for about 130 years. The intensity of miningrelated disturbance is higher than in most parts of the San Juan Mountains region, but actually is much less than the eastern half of the watershed (US BLM lands) and none of the mines moved millions of tons of rock and ore as in some of the eastern mines. The majority of the roughly one thousand mining sites on the USFS lands are very small (less than 100 tons or 70 cubic yards of dump material), are more than 2 miles from a major stream, or are so inaccessible as to prohibit reclamation. Twenty five sites have been considered by others to have significant size and potential for significant environmental degradation. These most significant mining areas were evaluated by multiple criteria, including tendency to generate acid or liberate toxic metals, observed acidic pH or dead vegetation (?kill zones?) below dumps or adits, potential mobility of metals, and likelihood of transport into streams of the watershed. In the author?s opinion, no single measurable parameter, such as metal concentration, is reliable for ranking significance or feasibility of reclamation. Rather, subjective estimates are required to evaluate combinations of, or interactions among, several parameters. The most subjective estimate in ranking feasibility of reclamation is the amount of natural and mine-related contamination at each mining area. Mitigation of natural contributions at mines or unmined areas is beyond the scope of these Abandoned Mine Lands (AML) investigations, but must be considered when planning reclamation. Available information for the 25 problem sites is adequate for ranking, but at some sites additional information on groundwater conditions is needed for a more reliable ranking and evaluation of reclamation methods.

  3. Chirp effects on impulsive vibrational spectroscopy: a multimode perspective.

    PubMed

    Wand, Amir; Kallush, Shimshon; Shoshanim, Ofir; Bismuth, Oshrat; Kosloff, Ronnie; Ruhman, Sanford

    2010-03-07

    The well-documented propensity of negatively-chirped pulses to enhance resonant impulsive Raman scattering has been rationalized in terms of a one pulse pump-dump sequence which "follows" the evolution of the excited molecules and dumps them back at highly displaced configurations. The aim of this study was to extend the understanding of this effect to molecules with many displaced vibrational modes in the presence of condensed surroundings. In particular, to define an optimally chirped pulse, to investigate what exactly it "follows" and to discover how this depends on the molecule under study. To this end, linear chirp effects on vibrational coherences in poly-atomics are investigated experimentally and theoretically. Chirped pump-impulsive probe experiments are reported for Sulforhodamine-B ("Kiton Red"), Betaine-30 and Oxazine-1 in ethanol solutions with <10 fs resolution. Numerical simulations, including numerous displaced modes and electronic dephasing, are conducted to reproduce experimental results. Through semi-quantitative reproduction of experimental results in all three systems we show that the effect of group velocity dispersion (GVD) on the buildup of ground state wave-packets depends on the pulse spectrum, on the displacements of vibrational modes upon excitation, on the detuning of the excitation pulses from resonance, and on electronic dephasing rates. Akin to scenarios described for frequency-domain resonance Raman, within the small-displacement regime each mode responds to excitation chirp independently and the optimal GVD is mode-specific. Highly-displaced modes entangle the dynamics of excitation in different modes, requiring a multi-dimensional description of the response. Rapid photochemistry and ultrafast electronic dephasing narrow the window of opportunity for coherent manipulations, leading to a reduced and similar optimal chirp for different modes. Finally, non-intuitive coherent aspects of chirp "following" are predicted in the small-displacement and slow-dephasing regime, which remain to be observed in experiment.

  4. Geochemical investigations and interim recommendations for priority abandoned mine sites, BLM lands, upper Animas River watershed, San Juan County, Colorado

    USGS Publications Warehouse

    Nash, J. Thomas

    1999-01-01

    Field observations, sampling of mine dumps and mine drainage waters, and laboratory studies of dump materials have been made at mining areas deemed to be on public lands administered by the U. S. Bureau of Land Management (BLM) in the Upper Animas River watershed. Results of chemical analyses of dump materials, leachates of those materials, and surface waters draining mines or dumps provide indications of where acid is generated or consumed, and metal concentrations below mines or dumps. Information on sites previously identified as needing reclamation is reviewed and available geochemical information is used to rank 26 sites into four classes of priority for reclamation. Although there are more than a thousand mining sites (productive mines and prospects) on BLM lands in the Upper Animas River watershed study area, the majority are very small (less than about 70 cubic yards of dump material), are more than 2 miles from a major stream, or so inaccessible as to prohibit reclamation. In the summers of 1997 and 1998 approximately 200 sites were observed and more than 100 of these that appeared to have the potential to geochemically impact the watershed were examined more carefully and sampled. Building upon the prior work of the BLM and associated agencies, this work attempted to identify the most significant sources of mine-related contamination and to rank those sites as to priority for reclamation. These most significant mining areas have been examined within a geologic framework and were evaluated by multiple criteria, including tendency to generate acid and release toxic metals, observed damage to vegetation, potential to release metals based on leach tests, and likelihood of transport into streams of the watershed. No single measurable parameter, such as metal concentration, can be used to rank the sites. Rather, subjective estimates are required to evaluate combinations or interactions among several parameters. The most subjective estimate, while ranking feasibility of reclamation, is the relative amounts of naturally occurring metals and acidity and mine-related contamination at each mining area. Mitigation of natural contributions at mines or unmined areas is beyond the scope of my studies, but should be considered when planning reclamation. Available information for the 26 priority sites is adequate for ranking, but at some sites additional information on groundwater conditions is needed for a more complete site evaluation.

  5. Added aluminum shielding to attenuate back scatter electrons from intra-oral lead shields.

    PubMed

    Weidlich, G A; Nuesch, C E; Fuery, J J

    1996-01-01

    An intra-oral lead shield was developed that consists of a lead base with an aluminum layer that is placed upstream of the lead base. Several such shields with various thicknesses of Al layers were manufactured and quantitatively evaluated in 6 MeV and 12 MeV electron radiation by Thermoluminescent dosimetry (TLD) measurements. The clinical relevance was established by using a 5 cm backscatter block down-stream of the lead shield to simulate anatomical structures of the head and a 0.5 cm superflab bolus upstream of the Al layers of the shield to simulate the patient's lip or cheek. The TLDs were placed between the Al layers of the shield and the superflab to determine the intra-oral skin dose. TLD exposure results revealed that 59.8% of the skin dose at 6 MeV and 45.1% of the skin dose at 12 MeV is due to backscattered electrons. Introduction of a 3.0 mm thick Al layer reduces the backscatter contribution to 13.5% of the back scatter dose at 6 MeV and 56.3% of the back scatter dose at 12 MeV electron radiation.

  6. Continuous all-optical deceleration of molecular beams and demonstration with Rb atoms

    NASA Astrophysics Data System (ADS)

    Long, Xueping; Jayich, Andrew; Campbell, Wesley

    2017-04-01

    Ultracold samples of molecules are desirable for a variety of applications, such as many-body physics, precision measurement and quantum information science. However, the pursuit of ultracold molecules has achieved limited success: spontaneous emission into many different dark states makes it hard to optically decelerate molecules to trappable speed. We propose to address this problem with a general optical deceleration technique that exploits a pump-dump pulse pair from a mode-locked laser. A molecular beam is first excited by a counter-propagating ``pump'' pulse. The molecular beam is then driven back to the initial ground state by a co-propagating ``dump'' pulse via stimulated emission. The delay between the pump and dump pulse is set to be shorter than the excited state lifetimes in order to limit decays to dark states. We report progress benchmarking this stimulated force by accelerating a cold sample of neutral Rb atoms.

  7. Back-streaming ion beam measurements in a Self Magnetic Insulated (SMP) electron diode

    NASA Astrophysics Data System (ADS)

    Mazarakis, Michael; Johnston, Mark; Kiefer, Mark; Leckbee, Josh; Webb, Timothy; Bennett, Nichelle; Droemer, Darryl; Welch, Dale; Nielsen, Dan; Ziska, Derek; Wilkins, Frank; Advance radiography department Team

    2014-10-01

    A self-magnetic pinch diode (SMP) is presently the electron diode of choice for high energy flash x-ray radiography utilizing pulsed power drivers. The Sandia National Laboratories RITS accelerator is presently fit with an SMP diode that generates very small electron beam spots. RITS is a Self-Magnetically Insulated Transmission Line (MITL) voltage adder that adds the voltage pulse of six 1.3 MV inductively insulated cavities. The diode's anode is made of high Z metal in order to produce copious and energetic flash x-rays for radiographic imaging of high areal density objects. In any high voltage inductive voltage adder (IVA) utilizing MITLs to transmit the power to the diode load, the precise knowledge of the accelerating voltage applied on the anode-cathode (A-K) gap is problematic. This is even more difficult in an SMP diode where the A-K gap is very small (~1 cm) and the diode region very hostile. We are currently measuring the back-streaming ion currents emitted from the anode and propagating through a hollow cathode tip. We then are evaluating the A-K gap voltage by ion time of flight measurements supplemented with filtered Rogowski coils. Sandia is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under Contract No. DE- AC04-94AL850.

  8. Iodine Beam Dump Design and Fabrication

    NASA Technical Reports Server (NTRS)

    Polzin, K. A.; Bradley, D. E.

    2017-01-01

    During the testing of electric thrusters, high-energy ions impacting the walls of a vacuum chamber can cause corrosion and/or sputtering of the wall materials, which can damage the chamber walls. The sputtering can also introduce the constituent materials of the chamber walls into an experiment, with those materials potentially migrating back to the test article and coating it with contaminants over time. The typical method employed in this situation is to install a beam dump fabricated from materials that have a lower sputter yield, thus reducing the amount of foreign material that could migrate towards the test article or deposit on anything else present in the vacuum facility.

  9. HIGH VOLTAGE ION SOURCE

    DOEpatents

    Luce, J.S.

    1960-04-19

    A device is described for providing a source of molecular ions having a large output current and with an accelerated energy of the order of 600 kv. Ions are produced in an ion source which is provided with a water-cooled source grid of metal to effect maximum recombination of atomic ions to molecular ions. A very high accelerating voltage is applied to withdraw and accelerate the molecular ions from the source, and means are provided for dumping the excess electrons at the lowest possible potentials. An accelerating grid is placed adjacent to the source grid and a slotted, grounded accelerating electrode is placed adjacent to the accelerating grid. A potential of about 35 kv is maintained between the source grid and accelerating grid, and a potential of about 600 kv is maintained between the accelerating grid and accelerating electrode. In order to keep at a minimum the large number of oscillating electrons which are created when such high voltages are employed in the vicinity of a strong magnetic field, a plurality of high voltage cascaded shields are employed with a conventional electron dumping system being employed between each shield so as to dump the electrons at the lowest possible potential rather than at 600 kv.

  10. Passive and active plasma deceleration for the compact disposal of electron beams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bonatto, A., E-mail: abonatto@lbl.gov; CAPES Foundation, Ministry of Education of Brazil, Brasília, DF 700040-020; Schroeder, C. B.

    2015-08-15

    Plasma-based decelerating schemes are investigated as compact alternatives for the disposal of high-energy beams (beam dumps). Analytical solutions for the energy loss of electron beams propagating in passive and active (laser-driven) schemes are derived. These solutions, along with numerical modeling, are used to investigate the evolution of the electron distribution, including energy chirp and total beam energy. In the active beam dump scheme, a laser-driver allows a more homogeneous beam energy extraction and drastically reduces the energy chirp observed in the passive scheme. These concepts could benefit applications requiring overall compactness, such as transportable light sources, or facilities operating atmore » high beam power.« less

  11. Collective Deceleration: Toward a Compact Beam Dump

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu, H.-C.; /Munich, Max Planck Inst. Quantenopt.; Tajima, T.

    With the increasing development of laser accelerators, the electron energy is already beyond GeV and even higher in near future. Conventional beam dump based on ionization or radiation loss mechanism is cumbersome and costly, also has radiological hazards. We revisit the stopping power of high-energy charged particles in matter and discuss the associated problem of beam dump from the point of view of collective deceleration. The collective stopping length in an ionized gas can be several orders of magnitude shorter than the Bethe-Bloch and multiple electromagnetic cascades stopping length in solid. At the mean time, the tenuous density of themore » gas makes the radioactivation negligible. Such a compact and non-radioactivating beam dump works well for short and dense bunches, which is typically generated from laser wakefield accelerator.« less

  12. A new dump system design for stray light reduction of Thomson scattering diagnostic system on EAST.

    PubMed

    Xiao, Shumei; Zang, Qing; Han, Xiaofeng; Wang, Tengfei; Yu, Jin; Zhao, Junyu

    2016-07-01

    Thomson scattering (TS) diagnostic is an important diagnostic for measuring electron temperature and density during plasma discharge. However, the measurement of Thomson scattering signal is disturbed by the stray light easily. The stray light sources in the Experimental Advanced Superconducting Tokamak (EAST) TS diagnostic system were analyzed by a simulation model of the diagnostic system, and simulation results show that the dump system is the primary stray light source. Based on the optics theory and the simulation analysis, a novel dump system including an improved beam trap was proposed and installed. The measurement results indicate that the new dump system can reduce more than 60% of the stray light for the diagnostic system, and the influence of stray light on the error of measured density decreases.

  13. Peer Assessment for Massive Open Online Courses (MOOCs)

    ERIC Educational Resources Information Center

    Suen, Hoi K.

    2014-01-01

    The teach-learn-assess cycle in education is broken in a typical massive open online course (MOOC). Without formative assessment and feedback, MOOCs amount to information dump or broadcasting shows, not educational experiences. A number of remedies have been attempted to bring formative assessment back into MOOCs, each with its own limits and…

  14. Influence of forest and rangeland management on anadromous fish habitat in Western North America: water transportation and storage of logs.

    Treesearch

    J.R. Sedell; W.S. Duval

    1985-01-01

    Environmental effects of water transportation of logs in western North America include the historical driving of logs in rivers and streams, and the current dumping, sorting, transportation, and storage of logs in rivers and estuaries in British Columbia and southeastern Alaska. The historical discussion focuses on habitat losses and volumes of...

  15. Mining-impacted sources of metal loading to an alpine stream based on a tracer-injection study, Clear Creek County, Colorado

    USGS Publications Warehouse

    Fey, David L.; Wirt, Laurie

    2007-01-01

    The largest sources of copper and zinc to the creek were from surface inflows from the adit, diffuse inflows from wetland areas, and leaching of dispersed mill tailings. Major instream processes included mixing between mining- and non-mining-impacted waters and the attenuation of iron, aluminum, manganese, and othermetals by precipitation or sorption. One year after the rerouting, the Zn and Cu loads in Leavenworth Creek from the adit discharge versus those from leaching of a large volume of dispersed mill tailings were approximately equal to, if not greater than, those before. The mine-waste dump does not appear to be a major source of metal loading. Any improvement that may have resulted from the elimination of adit flow across the dump was masked by higher adit discharge attributed to a larger snow pack. Although many mine remediation activities commonly proceed without prior scientific studies to identify the sources and pathways of metal transport, such strategies do not always translate to water-quality improvements in the stream. Assessment of sources and pathways to gain better understanding of the system is a necessary investment in the outcome of any successful remediation strategy.

  16. A new dump system design for stray light reduction of Thomson scattering diagnostic system on EAST

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xiao, Shumei; Zang, Qing, E-mail: zangq@ipp.ac.cn; Han, Xiaofeng

    Thomson scattering (TS) diagnostic is an important diagnostic for measuring electron temperature and density during plasma discharge. However, the measurement of Thomson scattering signal is disturbed by the stray light easily. The stray light sources in the Experimental Advanced Superconducting Tokamak (EAST) TS diagnostic system were analyzed by a simulation model of the diagnostic system, and simulation results show that the dump system is the primary stray light source. Based on the optics theory and the simulation analysis, a novel dump system including an improved beam trap was proposed and installed. The measurement results indicate that the new dump systemmore » can reduce more than 60% of the stray light for the diagnostic system, and the influence of stray light on the error of measured density decreases.« less

  17. Microbial Ecology Assessment of Mixed Copper Oxide/Sulfide Dump Leach Operation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bruhn, D F; Thompson, D N; Noah, K S

    1999-06-01

    Microbial consortia composed of complex mixtures of autotrophic and heterotrophic bacteria are responsible for the dissolution of metals from sulfide minerals. Thus, an efficient copper bioleaching operation depends on the microbial ecology of the system. A microbial ecology study of a mixed oxide/sulfide copper leaching operation was conducted using an "overlay" plating technique to differentiate and identify various bacterial consortium members of the genera Thiobacillus, Leptospirillum, Ferromicrobium, and Acidiphilium. Two temperatures (30C and 45C) were used to select for mesophilic and moderately thermophilic bacteria. Cell numbers varied from 0-106 cells/g dry ore, depending on the sample location and depth. Aftermore » acid curing for oxide leaching, no viable bacteria were recovered, although inoculation of cells from raffinate re-established a microbial population after three months. Due to the low pH of the operation, very few non-iron-oxidizing acidophilic heterotrophs were recovered. Moderate thermophiles were isolated from the ore samples. Pregnant liquor solutions (PLS) and raffinate both contained a diversity of bacteria. In addition, an intermittently applied waste stream that contained high levels of arsenic and fluoride was tested for toxicity. Twenty vol% waste stream in PLS killed 100% of the cells in 48 hours, indicating substantial toxicity and/or growth inhibition. The data indicate that bacteria populations can recover after acid curing, and that application of the waste stream to the dump should be avoided. Monitoring the microbial ecology of the leaching operation provided significant information that improved copper recovery.« less

  18. Radio frequency accelerating cavity having slotted irises for damping certain electromagnetic modes

    DOEpatents

    Palmer, Robert B.

    1991-01-01

    An accelerating cavity having one or more iris structures mounted therein for strongly damping unwanted frequencies that are generated in the cavity by bunches of particles in a particle beam that is accelerated through the cavity during its operation. Each of the iris structures is characterized by containing a plurality of radial slots therein that extend from the central aperture through the iris member to the perimeter thereof. The outer end of each of the radial slots includes an enlarged portion that is effective to prevent undesired frequencies from being reflected back into the center aperture of the iris member. Waveguide means connect the outer ends of the radial slots to frequency damping means or to a dump or dumps.

  19. Beam extraction and high stability operation of high current electron cyclotron resonance proton ion source.

    PubMed

    Roychowdhury, P; Mishra, L; Kewlani, H; Patil, D S; Mittal, K C

    2014-03-01

    A high current electron cyclotron resonance proton ion source is designed and developed for the low energy high intensity proton accelerator at Bhabha Atomic Research Centre. The plasma discharge in the ion source is stabilized by minimizing the reflected microwave power using four stub auto tuner and magnetic field. The optimization of extraction geometry is performed using PBGUNS code by varying the aperture, shape, accelerating gap, and the potential on the electrodes. While operating the source, it was found that the two layered microwave window (6 mm quartz plate and 2 mm boron nitride plate) was damaged (a fine hole was drilled) by the back-streaming electrons after continuous operation of the source for 3 h at beam current of 20-40 mA. The microwave window was then shifted from the line of sight of the back-streaming electrons and located after the water-cooled H-plane bend. In this configuration the stable operation of the high current ion source for several hours is achieved. The ion beam is extracted from the source by biasing plasma electrode, puller electrode, and ground electrode to +10 to +50 kV, -2 to -4 kV, and 0 kV, respectively. The total ion beam current of 30-40 mA is recorded on Faraday cup at 40 keV of beam energy at 600-1000 W of microwave power, 800-1000 G axial magnetic field and (1.2-3.9) × 10(-3) mbar of neutral hydrogen gas pressure in the plasma chamber. The dependence of beam current on extraction voltage, microwave power, and gas pressure is investigated in the range of operation of the ion source.

  20. Fuel cell system logic for differentiating between rapid and normal shutdown commands

    DOEpatents

    Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

    2000-01-01

    A method of controlling the operation of a fuel cell system wherein each shutdown command for the system is subjected to decision logic which determines whether the command should be a normal shutdown command or rapid shutdown command. If the logic determines that the shutdown command should be a normal shutdown command, then the system is shutdown in a normal step-by-step process in which the hydrogen stream is consumed within the system. If the logic determines that the shutdown command should be a rapid shutdown command, the hydrogen stream is removed from the system either by dumping to atmosphere or routing to storage.

  1. High performance N2O4/amine elements: Data dump covering. Task 1: Literature review

    NASA Technical Reports Server (NTRS)

    Hines, W. S.; Nurick, W. H.

    1974-01-01

    The phenomenon of reactive stream separation (RSS) in the N2O4/amine earth-storable propellant combinations is reviewed. Early theoretical models of RSS are presented, as are experimental combustion data under simulated rocket conditions. N2O4/amine combustion chemistry data is also provided. More recent work in the development of a comprehensive model is described.

  2. Strong-field dissociation of CS2+ via a pump/dump-like mechanism

    NASA Astrophysics Data System (ADS)

    Severt, T.; Zohrabi, M.; Betsch, K. J.; Ablikim, U.; Jochim, Bethany; Carnes, K. D.; Zeng, S.; Esry, B. D.; Ben-Itzhak, I.; Uhlíková, T.

    2014-05-01

    Laser-induced dissociation of the quasi-bound electronic ground state of CS2+ is investigated in intense laser pulses (<55 fs, <1016 W/cm2). Photodissociation is observed to be the dominant dissociation pathway; however, a more curious feature in the kinetic energy release spectrum suggests no significant energy gain from the initial states. We propose a pump/dump-like mechanism to explain this observed feature. Contrary to the conventional pump/dump control scheme, this process occurs within a single laser pulse, where the time delay is caused by the molecular structure. The process begins when the vibrational wavepacket in the electronic ground state of CS2+ is pumped into the electronic first excited state's continuum by a single photon. After a period of stretching at an energy above the potential barrier, the emission of a second photon is stimulated by the same laser pulse, most likely at the Condon point. Supported by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy, Grants DE-FG02-86ER13491 and DE-FG02-09ER16115. TU supported by GACR and MetaCentrum.

  3. Back-streaming ion emission and beam focusing on high power linear induction accelerator

    NASA Astrophysics Data System (ADS)

    Zhu, Jun; Chen, Nan; Yu, Haijun; Jiang, Xiaoguo; Wang, Yuan; Dai, Wenhua; Gao, Feng; Wang, Minhong; Li, Jin; Shi, Jinshui

    2011-08-01

    Ions released from target surfaces by impact of a high intensity and current electron beam can be accelerated and trapped in the beam potential, and further destroy the beam focus. By solving the 2D Poisson equation, we found that the charge neutralization factor of the ions to the beam under space charge limited condition is 1/3, which is large enough to disrupt the spot size. Therefore, the ion emission at the target in a single-pulse beam/target system must be source limited. Experimental results on the time-resolved beam profile measurement have also proven that. A new focus scheme is proposed in this paper to focus the beam to a small spot size with the existence of back-streaming ions. We found that the focal spot will move upstream as the charge neutralization factor increases. By comparing the theoretical and experimental focal length of the Dragon-I accelerator (20 MeV, 2.5 kA, 60 ns flattop), we found that the average neutralization factor is about 5% in the beam/target system.

  4. Long pulse acceleration of MeV class high power density negative H{sup −} ion beam for ITER

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Umeda, N., E-mail: umeda.naotaka@jaea.go.jp; Kojima, A.; Kashiwagi, M.

    2015-04-08

    R and D of high power density negative ion beam acceleration has been carried out at MeV test facility in JAEA to realize ITER neutral beam accelerator. The main target is H{sup −} ion beam acceleration up to 1 MeV with 200 A/m{sup 2} for 60 s whose pulse length is the present facility limit. For long pulse acceleration at high power density, new extraction grid (EXG) has been developed with high cooling capability, which electron suppression magnet is placed under cooling channel similar to ITER. In addition, aperture size of electron suppression grid (ESG) is enlarged from 14 mmmore » to 16 mm to reduce direct interception on the ESG and emission of secondary electron which leads to high heat load on the upstream acceleration grid. By enlarging ESG aperture, beam current increased 10 % at high current beam and total acceleration grid heat load reduced from 13 % to 10 % of input power at long pulse beam. In addition, heat load by back stream positive ion into the EXG is measured for the first time and is estimated as 0.3 % of beam power, while heat load by back stream ion into the source chamber is estimated as 3.5 ~ 4.0 % of beam power. Beam acceleration up to 60 s which is the facility limit, has achieved at 683 keV, 100 A/m{sup 2} of negative ion beam, whose energy density increases two orders of magnitude since 2011.« less

  5. Control of tunneling in a double-well potential with chirped laser pulses

    NASA Astrophysics Data System (ADS)

    Vatasescu, Mihaela

    2012-11-01

    We investigate the use of chirped laser pulses to control the tunneling dynamics in the 0g-(6s,6p3/2) double well of Cs2 coupled with other electronic surfaces. The possibility to manipulate the tunneling dynamics appears in a pump-dump scheme designed to form deeply bound cold molecules by photoassociation of two cold cesium atoms in the 0g-(6s,6p3/2) electronic state coupled with a3Σu+ (6s,6s) electronic state. The dump pulse is acting on the 0g-(6s,6p3/2) barrier and can be used to control the tunneling and to capture population in the inner well in deep vibrational levels out of tunneling resonances.

  6. Control of concerted two bond versus single bond dissociation in CH(3)Co(CO)(4) via an intermediate state using pump-dump laser pulses.

    PubMed

    Ambrosek, David; González, Leticia

    2007-10-07

    Wavepacket propagations on ab initio multiconfigurational two-dimensional potential energy surfaces for CH(3)Co(CO)(4) indicate that after irradiation to the lowest first and second electronic excited states, concerted dissociation of CH(3) and the axial CO ligand takes place. We employ a pump-dump sequence of pulses with appropriate frequencies and time delays to achieve the selective breakage of a single bond by controlling the dissociation angle. The pump and dump pulse sequence exploits the unbound surface where dissociation occurs in a counterintuitive fashion; stretching of one bond in an intermediate state enhances the single dissociation of the other bond.

  7. Dumping of auroral kilometric radiation caused by HF heating facility

    NASA Astrophysics Data System (ADS)

    Mogilevsky, M.; Romantsova, T.; Moiseenko, I.; Bosenger, T.; Rietveld, M.; Hanasz, J.

    2012-04-01

    We have use measurements of electromagnetic waves and plasma onboard of INTERBALL-2 satellite during joint experiment with Tromso HF heating facility. During the selected event the satellite crossed magnetic flux tube with a footprint at the ionosphere above heater. It was found significant dumping of AKR few minutes after the pumping was switched on. The most prominent dumping was detected at high frequency AKR (500-600 kHz) which were emitted at the height of 2-3 thousands km. Two possible mechanisms of this phenomenon are discussed: (i) reflection AKR from the region with increased electron density and (ii) suppression emission by decrease efficiency of the source caused up going plasma from the heated ionosphere.

  8. Four cavity efficiency enhanced magnetically insulated line oscillator

    DOEpatents

    Lemke, Raymond W.; Clark, Miles C.; Calico, Steve E.

    1998-04-21

    A four cavity, efficient magnetically insulated line oscillator (C4-E MILO) having seven vanes and six cavities formed within a tube-like structure surrounding a cathode. The C4-E MILO has a primary slow wave structure which is comprised of four vanes and the four cavities located near a microwave exit end of the tube-like structure. The primary slow wave structure is the four cavity (C4) portion of the magnetically insulated line oscillator (MILO). An RF choke is provided which is comprised of three of the vanes and two of the cavities. The RF choke is located near a pulsed power source portion of the tube-like structure surrounding the cathode. The RF choke increases feedback in the primary slow wave structure, prevents microwaves generated in the primary slow wave structure from propagating towards the pulsed power source and modifies downstream electron current so as to enhance microwave power generation. A beam dump/extractor is located at the exit end of the oscillator tube for extracting microwave power from the oscillator, and in conjunction with an RF extractor vane, which comprises the fourth vane of the primary slow wave structure (nearest the exit) having a larger gap radius than the other vanes of the primary SWS, comprises an RF extractor. Uninsulated electron flow is returned downstream towards the exit along an anode/beam dump region located between the beam dump/extractor and the exit where the RF is radiated at said RF extractor vane located near the exit and the uninsulated electron flow is disposed at the beam dump/extractor.

  9. Four cavity efficiency enhanced magnetically insulated line oscillator

    DOEpatents

    Lemke, R.W.; Clark, M.C.; Calico, S.E.

    1998-04-21

    A four cavity, efficient magnetically insulated line oscillator (C4-E MILO) having seven vanes and six cavities formed within a tube-like structure surrounding a cathode is disclosed. The C4-E MILO has a primary slow wave structure which is comprised of four vanes and the four cavities located near a microwave exit end of the tube-like structure. The primary slow wave structure is the four cavity portion of the magnetically insulated line oscillator (MILO). An RF choke is provided which is comprised of three of the vanes and two of the cavities. The RF choke is located near a pulsed power source portion of the tube-like structure surrounding the cathode. The RF choke increases feedback in the primary slow wave structure, prevents microwaves generated in the primary slow wave structure from propagating towards the pulsed power source and modifies downstream electron current so as to enhance microwave power generation. A beam dump/extractor is located at the exit end of the oscillator tube for extracting microwave power from the oscillator, and in conjunction with an RF extractor vane, which comprises the fourth vane of the primary slow wave structure (nearest the exit) having a larger gap radius than the other vanes of the primary SWS, comprises an RF extractor. Uninsulated electron flow is returned downstream towards the exit along an anode/beam dump region located between the beam dump/extractor and the exit where the RF is radiated at said RF extractor vane located near the exit and the uninsulated electron flow is disposed at the beam dump/extractor. 34 figs.

  10. Generation of anomalously energetic suprathermal electrons by an electron beam interacting with a nonuniform plasma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sydorenko, D.; Kaganovich, I. D.; Chen, L.

    Generation of anomalously energetic suprathermal electrons was observed in simulation of a high-voltage dc discharge with electron emission from the cathode. An electron beam produced by the emission interacts with the nonuniform plasma in the discharge via a two-stream instability. The energy transfer from the beam to the plasma electrons is ensured by the plasma nonuniformity. The electron beam excites plasma waves whose wavelength and phase speed gradually decrease towards anode. The waves with short wavelength near the anode accelerate plasma bulk electrons to suprathermal energies. The sheath near the anode reflects some of the accelerated electrons back into themore » plasma. These electrons travel through the plasma, reflect near the cathode, and enter the accelerating area again but with a higher energy than before. Such particles are accelerated to energies much higher than after the first acceleration. This mechanism plays a role in explaining earlier experimental observations of energetic suprathermal electrons in similar discharges.« less

  11. Turning a hazardous waste lagoon into reclaimed land for wildlife management: A case study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leong, A.K.

    Brownfields are turning back to green. This paper presents a case study of a former dump site for hazardous waste that has been remediated and will be developed into an enhanced wildlife management habitat. This successful remediation case combined various investigations, remedial designs, risk assessments, ecological studies, and engineering practices. 3 refs., 1 fig., 1 tab.

  12. Radio frequency accelerating cavity having slotted irises for damping certain electromagnetic modes

    DOEpatents

    Palmer, R.B.

    1991-05-21

    An accelerating cavity is disclosed having one or more iris structures mounted therein for strongly damping unwanted frequencies that are generated in the cavity by bunches of particles in a particle beam that is accelerated through the cavity during its operation. Each of the iris structures is characterized by containing a plurality of radial slots therein that extend from the central aperture through the iris member to the perimeter thereof. The outer end of each of the radial slots includes an enlarged portion that is effective to prevent undesired frequencies from being reflected back into the center aperture of the iris member. Waveguide means connect the outer ends of the radial slots to frequency damping means or to a dump or dumps. 17 figures.

  13. Kinetics of selenium release in mine waste from the Meade Peak Phosphatic Shale, Phosphoria Formation, Wooley Valley, Idaho, USA

    Treesearch

    Lisa L. Stillings; Michael C. Amacher

    2010-01-01

    Phosphorite from the Meade Peak Phosphatic Shale member of the Permian Phosphoria Formation has been mined in southeastern Idaho since 1906. Dumps of waste rock from mining operations contain high concentrations of Se which readily leach into nearby streams and wetlands. While the most common mineralogical residence of Se in the phosphatic shale is elemental Se, Se(0...

  14. Microbial Ecology Assessment of Mixed Copper Oxide/Sulfide Dump Leach Operation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bruhn, Debby Fox; Thompson, David Neal; Noah, Karl Scott

    1999-06-01

    Microbial consortia composed of complex mixtures of autotrophic and heterotrophic bacteria are responsible for the dissolution of metals from sulfide minerals. Thus, an efficient copper bioleaching operation depends on the microbial ecology of the system. A microbial ecology study of a mixed oxide/sulfide copper leaching operation was conducted using an "overlay" plating technique to differentiate and identify various bacterial consortium members of the genera Thiobacillus, “Leptospirillum”, “Ferromicrobium”, and Acidiphilium. Two temperatures (30°C and 45°C) were used to select for mesophilic and moderately thermophilic bacteria. Cell numbers varied from 0-106 cells/g dry ore, depending on the sample location and depth. Aftermore » acid curing for oxide leaching, no viable bacteria were recovered, although inoculation of cells from raffinate re-established a microbial population after three months. Due to low the pH of the operation, very few non-iron-oxidizing acidophilic heterotrophs were recovered. Moderate thermophiles were isolated from the ore samples. Pregnant liquor solutions (PLS) and raffinate both contained a diversity of bacteria. In addition, an intermittently applied waste stream that contained high levels of arsenic and fluoride was tested for toxicity. Twenty vol% waste stream in PLS killed 100% of the cells in 48 hours, indicating substantial toxicity and/or growth inhibition. The data indicate that bacteria populations can recover after acid curing, and that application of the waste stream to the dump should be avoided. Monitoring the microbial ecology of the leaching operation provided significant information that improved copper recovery.« less

  15. Can Small Countries Benefit from the E-waste Global Value Chain?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meine Pieter, Dijk van, E-mail: mpvandijk@iss.nl

    E-waste is a term used to cover items of all types of electrical and electronic equipment and its parts that have been discarded by the owners as waste without the intention of re-use, because this equipment has ceased to be of any value to its owners. E-waste is one of the fastestgrowing waste streams globally. Since the Rio Summit Earth summit organized by the United Nations in 1992, the concept of sustainability extends to rendering basic services such as Solid Waste Management and dealing with e-waste. People are afraid of e-waste because of its possible negative effects on health andmore » because it could pollute the environment. Indicators of unsustainable service provision concerninge-waste include irregular collection, open dumping, burning of solid and e-waste in open spaces. Often collection covers a small part of the country, cost recovery is limited or not existent, and one notes poor utilization of available resources with no or very limited reuse and recycling.« less

  16. Pyrolytic graphite collector development program

    NASA Technical Reports Server (NTRS)

    Wilkins, W. J.

    1982-01-01

    Pyrolytic graphite promises to have significant advantages as a material for multistage depressed collector electrodes. Among these advantages are lighter weight, improved mechanical stiffness under shock and vibration, reduced secondary electron back-streaming for higher efficiency, and reduced outgassing at higher operating temperatures. The essential properties of pyrolytic graphite and the necessary design criteria are discussed. This includes the study of suitable electrode geometries and methods of attachment to other metal and ceramic collector components consistent with typical electrical, thermal, and mechanical requirements.

  17. Horizontal angular VOR, nystagmus dumping, and sensation duration in spacelab SLS-1 crewmembers

    NASA Technical Reports Server (NTRS)

    Oman, C. M.; Balkwill, M. D.; Young, L. R. (Principal Investigator)

    1993-01-01

    In 1G, the apparent time constant (Td) of postrotatory SPV decay with the head tilted face down is 55% of that with head erect (Te). This phenomenon is called "nystagmus dumping" and has been attributed to G effects on VOR velocity storage. Similarly, postrotatory sensation duration with head tilted (Dd) is 32% of that when head erect (De). In parabolic flight, Te and De are 70% of 1-G values, but a pitch back dumping movement produces no further change. Te, Td, and Dd have not previously been measured in orbital flight. VOR and sensation duration was tested in 4 crewmembers in 4 preflight, 1 inflight (days 4 or 5) and 4 post flight sessions. Bitemporal EOG was recorded with eyes open in darkness. Instructions were to "gaze straight ahead," and indicate when "rotation sensation disappears or becomes ambiguous". Subjects were rotated CW and CCW head erect for 1 min at 120 degrees/s, stopped, and EOG was recorded for another 1 min. This procedure was then used to study dumping, except that immediately after chair stop, subjects pitched their head forward 90 degrees. SPV was calculated using order statistic filtering, and dropouts removed using an iterative model fitting method. Te and Td were determined by logarithmic linear regression of mean SPV for each subject. In orbit, 90 degrees pitch movement produced rapid subjective dumping, but not nystagmus dumping. Dd was noticeably shorter ("almost instantaneous") compared to preflight Dd. Te and Td in orbit were similar to preflight Te for 3/4 subjects (rather than to preflight Td as expected). No consistent VOR gain changes were seen in orbit. Although Te is known to decrease acutely in parabolic flight, a longer time constant was measured in 3/4 subjects after 4-5 days adaptation to weightlessness, suggesting a return of angular velocity storage.

  18. Note: Self-biased voltage to suppress secondary electrons by a ZnO varistor in a compact pulsed neutron generator

    NASA Astrophysics Data System (ADS)

    Yang, Z.; Li, X.; Li, J.; Long, J. D.; Lan, C. H.; Wang, T.; Dong, P.; He, J. L.

    2017-03-01

    A large amount of back streaming electrons will bring about a part of current drain on power supply, cause sparking or high-voltage breakdowns, and affect the neutron yield and waveform for a compact sealed-tube pulsed neutron generator. A novel idea which uses a ZnO varistor to provide a constant self-biased voltage to suppress the secondary electrons is introduced. The I-V curve for the ZnO varistor was measured in the experiment. The effects of suppressing the secondary electrons were investigated using a ZnO varistor, linear resistors, and an independent power supply, respectively. The results show that the secondary electrons are suppressed effectively by the compact ZnO varistor, while not increasing the size and the component of the device. It is a promising design for compact sealed-tube neutron generators.

  19. Picosecond rotationally resolved stimulated emission pumping spectroscopy of nitric oxide

    NASA Astrophysics Data System (ADS)

    Tanjaroon, Chakree; Reeve, Scott W.; Ford, Alan; Murry, W. Dean; Lyon, Kevin; Yount, Bret; Britton, Dan; Burns, William A.; Allen, Susan D.; Bruce Johnson, J.

    2012-01-01

    Stimulated emission pumping (SEP) experiments were performed on the nitric oxide molecule in a flow cell environment using lasers with pulse widths of 17-25 ps. A lambda excitation scheme, or ''pump-dump" arrangement, was employed with the pump laser tuned to the T 00 vibronic band origin ( λ=226.35(1)nm) of the A2Σ+( v' = 0, J') ← X2Π1/2( v″ = 0, J″) and the dump laser scanned from 246-248 nm within the A2Σ+( v' = 0, J') → X2Π1/2( v″ = 2, J″) transition. The rotationally resolved SEP spectra were measured by observing the total fluorescence within the A2Σ+( v' = 0, J') → X2Π1/2( v″ = 1, J″) transition between 235 nm and 237.2 nm while scanning the dump laser wavelengths. Multiple rotational states were excited due to the broad laser bandwidth. Measurements showed that the resolved rotational structure depended on the energy and bandwidth of the applied pump and dump laser pulses. Analysis of the observed fluorescence depletion signals yielded an average percent fluorescence depletion of about 19% when λ=226.35(1)nm and λ=247.91(1)nm. This value reflects the percent transfer of the NO population from the A2Σ+( V' = 0, J') excited electronic state to the X2Π1/2( v″ = 2, J″) ground electronic state. The maximum expected depletion is 50% in the limit of dump saturation. Selective excitation of NO at the bandhead provides good spectral discrimination from the background emission and noise and unambiguously confirms the identity of the emitter.

  20. 75 FR 22524 - Ocean Dumping; Designation of Ocean Dredged Material Disposal Sites Offshore of the Siuslaw River...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-29

    ... location to dispose of material dredged from the Siuslaw River navigation channel, and to provide a... sediments from Site A back into the dredged channel resulted in a selection of disposal Sites B and C by the... conflicts. The final Sites are located close to the approach to the Siuslaw River entrance channel but are...

  1. Linear beam dynamics and ampere class superconducting RF cavities at RHIC

    NASA Astrophysics Data System (ADS)

    Calaga, Rama R.

    The Relativistic Heavy Ion Collider (RHIC) is a hadron collider designed to collide a range of ions from protons to gold. RHIC operations began in 2000 and has successfully completed five physics runs with several species including gold, deuteron, copper, and polarized protons. Linear optics and coupling are fundamental issues affecting the collider performance. Measurement and correction of optics and coupling are important to maximize the luminosity and sustain stable operation. A numerical approach, first developed at SLAC, was implemented to measure linear optics from coherent betatron oscillations generated by ac dipoles and recorded at multiple beam position monitors (BPMs) distributed around the collider. The approach is extended to a fully coupled 2D case and equivalence relationships between Hamiltonian and matrix formalisms are derived. Detailed measurements of the transverse coupling terms are carried out at RHIC and correction strategies are applied to compensate coupling both locally and globally. A statistical approach to determine BPM reliability and performance over the past three runs and future improvements also discussed. Aiming at a ten-fold increase in the average heavy-ion luminosity, electron cooling is the enabling technology for the next luminosity upgrade (RHIC II). Cooling gold ion beams at 100 GeV/nucleon requires an electron beam of approximately 54 MeV and a high average current in the range of 50-200 mA. All existing e-Coolers are based on low energy DC accelerators. The only viable option to generate high current, high energy, low emittance CW electron beam is through a superconducting energy-recovery linac (SC-ERL). In this option, an electron beam from a superconducting injector gun is accelerated using a high gradient (˜ 20 MV/m) superconducting RF (SRF) cavity. The electrons are returned back to the cavity with a 180° phase shift to recover the energy back into the cavity before being dumped. A design and development of a half-cell electron gun and a five-cell SRF linac cavity are presented. Several RF and beam dynamics issues ultimately resulting in an optimum cavity design are discussed in detail.

  2. Potential risk assessment in stream sediments, soils and waters after remediation in an abandoned W>Sn mine (NE Portugal).

    PubMed

    Antunes, I M H R; Gomes, M E P; Neiva, A M R; Carvalho, P C S; Santos, A C T

    2016-11-01

    The mining complex of Murçós belongs to the Terras de Cavaleiros Geopark, located in Trás-os-Montes region, northeast Portugal. A stockwork of NW-SE-trending W>Sn quartz veins intruded Silurian metamorphic rocks and a Variscan biotite granite. The mineralized veins contain mainly quartz, cassiterite, wolframite, scheelite, arsenopyrite, pyrite, sphalerite, chalcopyrite, galena, rare pyrrhotite, stannite, native bismuth and also later bismuthinite, matildite, joseite, roosveltite, anglesite, scorodite, zavaritskite and covellite. The exploitation produced 335t of a concentrate with 70% of W and 150t of another concentrate with 70% of Sn between 1948 and 1976. The exploitation took place mainly in four open pit mines as well as underground. Three lakes were left in the area. Remediation processes of confination and control of tailings and rejected materials and phytoremediation with macrophytes from three lakes were carried out between 2005 and 2007. Stream sediments, soils and water samples were collected in 2008 and 2009, after the remediation process. Most stream sediments showed deficiency or minimum enrichment for metals. The sequential enrichment factor in stream sediments W>Bi>As>U>Cd>Sn=Ag>Cu>Sb>Pb>Be>Zn is mainly associated with the W>Sn mineralizations. Stream sediments receiving drainage of a mine dump were found to be significantly to extremely enriched with W, while stream sediments and soils were found to be contaminated with As. Two soil samples collected around mine dumps and an open pit lake were also found to be contaminated with U. The waters from the Murçós W>Sn mine area were acidic to neutral. After the remediation, the surface waters were contaminated with F(-), Al, As, Mn and Ni and must not be used for human consumption, while open pit lake waters must also not be used for agriculture because of contamination with F(-), Al, Mn and Ni. In most waters, the As occurred as As (III), which is toxic and is easily mobilized in the drainage system. The remediation promoted a decrease in metals and As concentrations of soils and waters, however the applied processes were not enough to rehabilitate the area. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Protecting and Restoring Streams in an Urbanizing World: Back to Square One

    EPA Science Inventory

    Headwater streams represent a majority (up to 70%) of the stream length in the United States. Because of their position and prevalence in the landscape, these small streams are often piped or filled to accommodate development, resulting in impaired geomorphology, hydrology, wate...

  4. Coherent control of the formation of cold heteronuclear molecules by photoassociation

    NASA Astrophysics Data System (ADS)

    de Lima, Emanuel F.

    2017-01-01

    We consider the formation of cold diatomic molecules in the electronic ground state by photoassociation of atoms of dissimilar species. A combination of two transition pathways from the free colliding pair of atoms to a bound vibrational level of the electronic molecular ground state is envisioned. The first pathway consists of a pump-dump scheme with two time-delayed laser pulses in the near-infrared frequency domain. The pump pulse drives the transition to a bound vibrational level of an excited electronic state, while the dump pulse transfers the population to a bound vibrational level of the electronic ground state. The second pathway takes advantage of the existing permanent dipole moment and employs a single pulse in the far-infrared domain to drive the transition from the unbound atoms directly to a bound vibrational level in the electronic ground state. We show that this scheme offers the possibility to coherently control the photoassociation yield by manipulating the relative phase and timing of the pulses. The photoassociation mechanism is illustrated for the formation of cold LiCs molecules.

  5. Geospatial Assessment of Cholera in a Rapidly Urbanizing Environment.

    PubMed

    Olanrewaju, Olajumoke Esther; Adepoju, Kayode Adewale

    2017-01-01

    This study mapped out and investigated the spatial relationship between cholera incidences and environmental risk factors in the study area. The study area was stratified into eight zones. Water samples from each zone were collected and analyzed to determine the colony forming units. GIS layers including housing density, digitized roads, rivers, buildings, and cholera incidence data from hospital archives were also collected and analyzed using ArcGIS 10.1. It was observed that there was an association between the ERFs ( p < 0.001). Similarly, 18 out of the 44 waste dump sites, seven out of 18 markets, and two out of 36 abattoirs were found near the historical cholera cases. Similarly, 4 (21.1%) locations were traced to be predominantly close to rivers and waste dump site. All the historical cholera cases were found adjoining to roads and buildings. Highest CFU count was found in the wells and streams of areas with a cluster of all the environmental risk factors and high housing density. This study revealed that waste dump sites and market had the highest predisposing attribute while the least was abattoir. The uniqueness of the study lies in the combination of mapping and microbial analyses to identify and assess the pattern of cholera risk and also to provide clear information for development of strategies for environmental supervision.

  6. Dark Matter Search in a Beam-Dump eXperiment (BDX) at Jefferson Lab

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Battaglieri, M.

    MeV-GeV dark matter (DM) is theoretically well motivated but remarkably unexplored. This proposal presents the MeV-GeV DM discovery potential for amore » $$\\sim$$1 m$^3$ segmented CsI(Tl) scintillator detector placed downstream of the Hall A beam-dump at Jefferson Lab, receiving up to 10$$^{22}$$ electrons-on-target (EOT) in 285 days. This experiment (Beam-Dump eXperiment or BDX) would be sensitive to elastic DM-electron and to inelastic DM scattering at the level of 10 counts per year, reaching the limit of the neutrino irreducible background. The distinct signature of a DM interaction will be an electromagnetic shower of few hundreds of MeV, together with a reduced activity in the surrounding active veto counters. A detailed description of the DM particle $$\\chi$$ production in the dump and subsequent interaction in the detector has been performed by means of Monte Carlo simulations. Different approaches have been used to evaluate the expected backgrounds: the cosmogenic background has been extrapolated from the results obtained with a prototype detector running at INFN-LNS (Italy), while the beam-related background has been evaluated by GEANT4 Monte Carlo simulations. The proposed experiment will be sensitive to large regions of DM parameter space, exceeding the discovery potential of existing and planned experiments in the MeV-GeV DM mass range by up to two orders of magnitude.« less

  7. Cellulose-Enriched Microbial Communities from Leaf-Cutter Ant (Atta colombica) Refuse Dumps Vary in Taxonomic Composition and Degradation Ability

    DOE PAGES

    Lewin, Gina R.; Johnson, Amanda L.; Soto, Rolando D. Moreira; ...

    2016-03-21

    Deconstruction of the cellulose in plant cell walls is critical for carbon flow through ecosystems and for the production of sustainable cellulosic biofuels. Our understanding of cellulose deconstruction is largely limited to the study of microbes in isolation, but in nature, this process is driven by microbes within complex communities. In Neotropical forests, microbes in leaf-cutter ant refuse dumps are important for carbon turnover. These dumps consist of decaying plant material and a diverse bacterial community, as shown here by electron microscopy. To study the portion of the community capable of cellulose degradation, we performed enrichments on cellulose using materialmore » from five Atta colombica refuse dumps. The ability of enriched communities to degrade cellulose varied significantly across refuse dumps. 16S rRNA gene amplicon sequencing of enriched samples identified that the community structure correlated with refuse dump and with degradation ability. Overall, samples were dominated by Bacteroidetes, Gammaproteobacteria, and Betaproteobacteria. Half of abundant operational taxonomic units (OTUs) across samples were classified within general containing known cellulose degraders, including Acidovorax, the most abundant OTU detected across samples, which was positively correlated with cellulolytic ability. Lastly, a representative Acidovorax strain was isolated, but did not grow on cellulose alone. Phenotypic and compositional analyses of enrichment cultures, such as those presented here, help link community composition with cellulolytic ability and provide insight into the complexity of community-based cellulose degradation.« less

  8. Cellulose-Enriched Microbial Communities from Leaf-Cutter Ant (Atta colombica) Refuse Dumps Vary in Taxonomic Composition and Degradation Ability

    PubMed Central

    Lewin, Gina R.; Johnson, Amanda L.; Soto, Rolando D. Moreira; Perry, Kailene; Book, Adam J.; Horn, Heidi A.; Pinto-Tomás, Adrián A.; Currie, Cameron R.

    2016-01-01

    Deconstruction of the cellulose in plant cell walls is critical for carbon flow through ecosystems and for the production of sustainable cellulosic biofuels. Our understanding of cellulose deconstruction is largely limited to the study of microbes in isolation, but in nature, this process is driven by microbes within complex communities. In Neotropical forests, microbes in leaf-cutter ant refuse dumps are important for carbon turnover. These dumps consist of decaying plant material and a diverse bacterial community, as shown here by electron microscopy. To study the portion of the community capable of cellulose degradation, we performed enrichments on cellulose using material from five Atta colombica refuse dumps. The ability of enriched communities to degrade cellulose varied significantly across refuse dumps. 16S rRNA gene amplicon sequencing of enriched samples identified that the community structure correlated with refuse dump and with degradation ability. Overall, samples were dominated by Bacteroidetes, Gammaproteobacteria, and Betaproteobacteria. Half of abundant operational taxonomic units (OTUs) across samples were classified within genera containing known cellulose degraders, including Acidovorax, the most abundant OTU detected across samples, which was positively correlated with cellulolytic ability. A representative Acidovorax strain was isolated, but did not grow on cellulose alone. Phenotypic and compositional analyses of enrichment cultures, such as those presented here, help link community composition with cellulolytic ability and provide insight into the complexity of community-based cellulose degradation. PMID:26999749

  9. Cellulose-Enriched Microbial Communities from Leaf-Cutter Ant (Atta colombica) Refuse Dumps Vary in Taxonomic Composition and Degradation Ability

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lewin, Gina R.; Johnson, Amanda L.; Soto, Rolando D. Moreira

    Deconstruction of the cellulose in plant cell walls is critical for carbon flow through ecosystems and for the production of sustainable cellulosic biofuels. Our understanding of cellulose deconstruction is largely limited to the study of microbes in isolation, but in nature, this process is driven by microbes within complex communities. In Neotropical forests, microbes in leaf-cutter ant refuse dumps are important for carbon turnover. These dumps consist of decaying plant material and a diverse bacterial community, as shown here by electron microscopy. To study the portion of the community capable of cellulose degradation, we performed enrichments on cellulose using materialmore » from five Atta colombica refuse dumps. The ability of enriched communities to degrade cellulose varied significantly across refuse dumps. 16S rRNA gene amplicon sequencing of enriched samples identified that the community structure correlated with refuse dump and with degradation ability. Overall, samples were dominated by Bacteroidetes, Gammaproteobacteria, and Betaproteobacteria. Half of abundant operational taxonomic units (OTUs) across samples were classified within general containing known cellulose degraders, including Acidovorax, the most abundant OTU detected across samples, which was positively correlated with cellulolytic ability. Lastly, a representative Acidovorax strain was isolated, but did not grow on cellulose alone. Phenotypic and compositional analyses of enrichment cultures, such as those presented here, help link community composition with cellulolytic ability and provide insight into the complexity of community-based cellulose degradation.« less

  10. Apparatus and process for the refrigeration, liquefaction and separation of gases with varying levels of purity

    DOEpatents

    Bingham, Dennis N.; Wilding, Bruce M.; McKellar, Michael G.

    2002-01-01

    A process for the separation and liquefaction of component gasses from a pressurized mix gas stream is disclosed. The process involves cooling the pressurized mixed gas stream in a heat exchanger so as to condensing one or more of the gas components having the highest condensation point; separating the condensed components from the remaining mixed gas stream in a gas-liquid separator; cooling the separated condensed component stream by passing it through an expander; and passing the cooled component stream back through the heat exchanger such that the cooled component stream functions as the refrigerant for the heat exchanger. The cycle is then repeated for the remaining mixed gas stream so as to draw off the next component gas and further cool the remaining mixed gas stream. The process continues until all of the component gases are separated from the desired gas stream. The final gas stream is then passed through a final heat exchanger and expander. The expander decreases the pressure on the gas stream, thereby cooling the stream and causing a portion of the gas stream to liquify within a tank. The portion of the gas which is hot liquefied is passed back through each of the heat exchanges where it functions as a refrigerant.

  11. Apparatus and process for the refrigeration, liquefaction and separation of gases with varying levels of purity

    DOEpatents

    Bingham, Dennis N.; Wilding, Bruce M.; McKellar, Michael G.

    2000-01-01

    A process for the separation and liquefaction of component gasses from a pressurized mix gas stream is disclosed. The process involves cooling the pressurized mixed gas stream in a heat exchanger so as to condense one or more of the gas components having the highest condensation point; separating the condensed components from the remaining mixed gas stream in a gas-liquid separator; cooling the separated condensed component stream by passing it through an expander; and passing the cooled component stream back through the heat exchanger such that the cooled component stream functions as the refrigerant for the heat exchanger. The cycle is then repeated for the remaining mixed gas stream so as to draw off the next component gas and further cool the remaining mixed gas stream. The process continues until all of the component gases are separated from the desired gas stream. The final gas stream is then passed through a final heat exchanger and expander. The expander decreases the pressure on the gas stream, thereby cooling the stream and causing a portion of the gas stream to liquify within a tank. The portion of the gas which is not liquefied is passed back through each of the heat exchanges where it functions as a refrigerant.

  12. High-latitude observations of solar wind streams and coronal holes

    NASA Technical Reports Server (NTRS)

    Ricket, B. J.; Sime, D. G.; Crockett, W. R.; Tousey, R.; Sheeley, N. R., Jr.

    1976-01-01

    Interplanetary scintillation observations of the solar wind velocity during 1973 and the first part of 1974 reveal several corotating high-speed streams. These streams, of heliographic latitudes from +40 deg to -60 deg, have been mapped back to the vicinity of the sun and have been compared with coronal holes identified in wide band XUV solar images taken during the manned portions of the Skylab mission. There is some evidence that the high-speed streams are preferentially associated with coronal holes and that they can spread out from the hole boundaries up to about 20 deg in latitude. However, this association is not one to one; streams are observed which do not map back to coronal holes, and holes are observed which do not lie at the base of streams. To the extent that a statistical interpretation is possible the association is not highly significant, but individual consideration of streams and holes suggests that the statistical result is biased somewhat against a strong correlation.

  13. Continuous all-optical deceleration of molecular beams

    NASA Astrophysics Data System (ADS)

    Jayich, Andrew; Chen, Gary; Long, Xueping; Wang, Anna; Campbell, Wesley

    2014-05-01

    A significant impediment to generating ultracold molecules is slowing a molecular beam to velocities where the molecules can be cooled and trapped. We report on progress toward addressing this issue with a general optical deceleration technique for molecular and atomic beams. We propose addressing the molecular beam with a pump and dump pulse sequence from a mode-locked laser. The pump pulse counter-propagates with respect to the beam and drives the molecules to the excited state. The dump pulse co-propagates and stimulates emission, driving the molecules back to the ground state. This cycle transfers 2 ℏk of momentum and can generate very large optical forces, not limited by the spontaneous emission lifetime of the molecule or atom. Importantly, avoiding spontaneous emission limits the branching to dark states. This technique can later be augmented with cooling and trapping. We are working towards demonstrating this optical force by accelerating a cold atomic sample.

  14. Abundance of western red-backed salamanders (Plethodon vehiculum) in the Washington Coast Range after headwater stream-buffer manipulation

    Treesearch

    Randall J. Wilk; Jeffrey D. Ricklefs; Martin G. Raphael

    2014-01-01

    We evaluated the effect of forest riparian alternative tree buffer designs on Western Red-backed Salamanders (Plethodon vehiculum) along headwater stream banks in managed forests of the Washington Coast Range. We used pit trap live removals in early autumn to estimate relative abundances of surface-active salamanders before and after 3 levels of riparian buffer...

  15. Estimation of Airborne Radioactivity Induced by 8-GeV-Class Electron LINAC Accelerator.

    PubMed

    Asano, Yoshihiro

    2017-10-01

    Airborne radioactivity induced by high-energy electrons from 6 to 10 GeV is estimated by using analytical methods and the Monte Carlo codes PHITS and FLUKA. Measurements using a gas monitor with a NaI(Tl) scintillator are carried out in air from a dump room at SACLA, an x-ray free-electron laser facility with 7.8-GeV electrons and are compared to the simulations.

  16. Stimulated parametric emission microscopy.

    PubMed

    Isobe, Keisuke; Kataoka, Shogo; Murase, Rena; Watanabe, Wataru; Higashi, Tsunehito; Kawakami, Shigeki; Matsunaga, Sachihiro; Fukui, Kiichi; Itoh, Kazuyoshi

    2006-01-23

    We propose a novel microscopy technique based on the four-wave mixing (FWM) process that is enhanced by two-photon electronic resonance induced by a pump pulse along with stimulated emission induced by a dump pulse. A Ti:sapphire laser and an optical parametric oscillator are used as light sources for the pump and dump pulses, respectively. We demonstrate that our proposed FWM technique can be used to obtain a one-dimensional image of ethanol-thinned Coumarin 120 solution sandwiched between a hole-slide glass and a cover slip, and a two-dimensional image of a leaf of Camellia sinensis.

  17. Quarry waste management and recovery: first results connected to Carrara marble ravaneti (Italy)

    NASA Astrophysics Data System (ADS)

    Antonella Dino, Giovanna; Chiappino, Claudia; Rossetti, Piergiorgio

    2017-04-01

    Quarry waste (QW) represents a huge economic and environmental issue, due to loss of resources and to economic and environmental costs connected to waste management and landfilling activities. In many cases, valuable Raw Materials (RM) and Secondary Raw Materials (SRM) can be supplied by enhancing the QW recovery. In Italy large amounts of QW have been and still are dumped: such materials, if their quality (chemical, mineralogical, physical characteristics) and quantity are adequate, and if the impacts connected to their management are positive, can represent a valuable resource for SRM exploitation. Several dimension stone quarries have been and are interested by researches as for QW exploitation. Some researches show positive results, which are the basis for QW recovery (both from waste streams and from quarry dumps exploitation): a noticeable example is represented by Carrara marble waste. The Carrara quarry basin is characterized by ca. one hundred quarries for colored and white marble exploitation. The waste production can be summarized in: 80 Mm3 waste present in old quarry dumps (Ravaneti) and 3 Mm3/y of waste stream from quarrying activities. At present only 0.5 Mm3/y of QW is exploited for SRM production, causing a huge loss of resource. This has been the background for a preliminary research, on Carrara marble Ravaneti characterization, which was carried out thanks to the close cooperation between University of Torino, Società Apuana Marmi srl, and SET srl. In 2015, two QW dumping areas, Calocara and Lorano, were selected as representative for sampling activities. Three main sample categories were individuated based on granulometry (0.5-4 mm, 0-25 mm, 0-150 mm) to be characterized (size distribution, density, Atterberg limits, Los Angeles test, freezing and heat tests, flat and shape indexes, geochemistry, mineralogy). The results obtained are promising: the physical characterization shows an attitude for Carrara QW to be recovered as crushed materials for embankments and armour stone. Furthermore, the mineralogical and geochemical analyses show that these materials, being composed of nearly pure CaCO3, could find a proper application in high value products, as filler for paper, rubber, paint, plastic, etc. These data need to be confirmed by other analyses, thus a systematic characterization of QW present in the different quarry dumps is going to be programmed. R&D is strategic to solve problems connected to QW and landscape management. The cooperation between private Companies, Research Centers and Local Authorities is fundamental to reach the target, in terms of experimentation of new products (for civil works and infrastructure, building industry, agronomy, high-tech, etc.). Furthermore, if the stone industry aims at guaranteeing the systematic and convenient SRM recovery from QW, a change in exploitation and working activities has to be planned (eg. selection of the potential SRMs; dedicated stock areas for selected SRM; proper treatments depending on the kinds of reuse; treatment-activity protocols to produce each new product, etc.).

  18. 75 FR 32533 - WTO Dispute Settlement Proceeding Regarding United States-Anti-Dumping Measures on Certain Shrimp...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-08

    ... should be submitted electronically to http:[sol][sol] www.regulations.gov , docket number USTR-2010-0008. If you are unable to submit comments using http:[sol][sol] www.regulations.gov , please contact Sandy.... Persons may submit public comments electronically to http:[sol][sol] www.regulations.gov docket number...

  19. Thermal analysis of injection beam dump of high-intensity rapid-cycling synchrotron in J-PARC

    NASA Astrophysics Data System (ADS)

    Kamiya, J.; Saha, P. K.; Yamamoto, K.; Kinsho, M.; Nihei, T.

    2017-10-01

    The beam dump at the beam injection area in the J-PARC 3-GeV rapid cycling synchrotron (RCS) accepts beams that pass through the charge exchange foil without ideal electron stripping during the multi-turn beam injection. The injection beam dump consists of the beam pipe, beam stopper, radiation shield, and cooling mechanism. The ideal beam power into the injection beam dump is 400 W in the case of design RCS extraction beam power of 1 MW with a healthy foil, which has 99.7 % charge stripping efficiency. On the other hand, as a radiation generator, the RCS is permitted to be operated with maximum average beam power of 4 kW into the injection beam dump based on the radiation shielding calculation, in consideration of lower charge stripping efficiency due to the foil deterioration. In this research, to evaluate the health of the RCS injection beam dump system from the perspective of the heat generation, a thermal analysis was performed based on the actual configuration with sufficiently large region, including the surrounding concrete and soil. The calculated temperature and heat flux density distribution showed the validity of the mesh spacing and model range. The calculation result showed that the dumped 4 kW beam causes the temperature to increase up to 330, 400, and 140 °C at the beam pipe, beam stopper, and radiation shield, respectively. Although these high temperatures induce stress in the constituent materials, the calculated stress values were lower than the ultimate tensile strength of each material. Transient temperature analysis of the beam stopper, which simulated the sudden break of the charge stripper foil, demonstrated that one bunched beam pulse with the maximum beam power does not lead to a serious rise in the temperature of the beam stopper. Furthermore, from the measured outgassing rate of stainless steel at high temperature, the rise in beam line pressure due to additive outgassing from the heated beam pipe was estimated to have a negligible effect on beam line pressure. The flow and results of the evaluation in this analysis would provide a good indication for both the verification of the existing beam dumps, and the design of beam dumps in new accelerators with higher intensity beam.

  20. Mechanical characterization of municipal solid waste from two waste dumps at Delhi, India.

    PubMed

    Ramaiah, B J; Ramana, G V; Datta, Manoj

    2017-10-01

    The article presents the physical and mechanical properties of the emplaced municipal solid waste (MSW) recovered from different locations of the Ghazipur and Okhla dumps both located at Delhi, India. Mechanical compressibility and shear strength of the collected MSW were evaluated using a 300×300mm direct shear (DS) shear box. Compression ratio (C c ') of MSW at these two dumps varied between 0.11 and 0.17 and is falling on the lower bound of the range (0.1-0.5) of the data reported in the literature for MSW. Low C c ' of MSW is attributed to the relatively low percentages of compressible elements such as textiles, plastics and paper, coupled with relatively high percentages of inert materials such as soil-like and gravel sized fractions. Shear strength of MSW tested is observed to be displacement dependent. The mobilized shear strength parameters i.e., the apparent cohesion intercept (c') and friction angle (ϕ') of MSW at these two dumps are best characterized by c'=13kPa and ϕ'=23° at 25mm displacement and c'=17kPa and ϕ'=34° at 55mm displacement and are in the range reported for MSW in the literature. A large database on the shear strength of MSW from 18 countries that includes: the experimental data from 277 large-scale DS tests (in-situ and laboratory) and the data from back analysis of 11 failed landfill slopes is statistically analyzed. Based on the analysis, a simple linear shear strength envelope, characterized by c'=17kPa and ϕ'=32°, is proposed for MSW for preliminary use in the absence of site-specific data for stability evaluation of the solid waste landfill under drained conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. System level latchup mitigation for single event and transient radiation effects on electronics

    DOEpatents

    Kimbrough, J.R.; Colella, N.J.

    1997-09-30

    A ``blink`` technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection circuitry, power dump logic circuitry, and energy limiting measures with autonomous recovery. The event detection circuitry includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation. The current sensing circuitry is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation or by ion-induced destructive latchup of a semiconductor device. The power dump circuitry includes power dump logic circuitry having a first input terminal connected to the output terminal of the ionizing radiation pulse detection circuitry and having a second input terminal connected to the output terminal of the current sensing circuitry. The power dump logic circuitry provides an output signal to the input terminal of the circuitry for opening the power bus and the circuitry for shorting the power bus to a ground potential to remove power from the power bus. The energy limiting circuitry with autonomous recovery includes circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential. The circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential includes a series FET and a shunt FET. The invention provides for self-contained sensing for latchup, first removal of power to protect latched components, and autonomous recovery to enable transparent operation of other system elements. 18 figs.

  2. System level latchup mitigation for single event and transient radiation effects on electronics

    DOEpatents

    Kimbrough, Joseph Robert; Colella, Nicholas John

    1997-01-01

    A "blink" technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection circuitry, power dump logic circuitry, and energy limiting measures with autonomous recovery. The event detection circuitry includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation. The current sensing circuitry is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation or by ion-induced destructive latchup of a semiconductor device. The power dump circuitry includes power dump logic circuitry having a first input terminal connected to the output terminal of the ionizing radiation pulse detection circuitry and having a second input terminal connected to the output terminal of the current sensing circuitry. The power dump logic circuitry provides an output signal to the input terminal of the circuitry for opening the power bus and the circuitry for shorting the power bus to a ground potential to remove power from the power bus. The energy limiting circuitry with autonomous recovery includes circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential. The circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential includes a series FET and a shunt FET. The invention provides for self-contained sensing for latchup, first removal of power to protect latched components, and autonomous recovery to enable transparent operation of other system elements.

  3. Enhanced Alignment Techniques for the Thomson Scattering Diagnostic on the Lithium Tokamak eXperiment (LTX)

    NASA Astrophysics Data System (ADS)

    Merino, Enrique; Kozub, Tom; Boyle, Dennis; Lucia, Matthew; Majeski, Richard; Kaita, Robert; Schmitt, John C.; Leblanc, Benoit; Diallo, Ahmed; Jacobson, C. M.

    2014-10-01

    The Thomson Scattering (TS) System in LTX is used to measure electron temperature and density profiles of core and edge plasmas. In view of TS measurements showing low signal-to-noise and high stray light, numerous improvements were performed in recent months. These will allow for better measurements. Due to the nature of LTX's lithium coated walls, a particular challenge was presented by alignment procedures which required insertion and precise positioning of equipment in the vacuum vessel without breaking vacuum. To overcome these difficulties, the laser flight tubes were removed and an alignment probe setup placed along the beam line on a differentially pumped assembly. The probe was then driven into the vacuum vessel and back-illumination of the viewing optics on it allowed for alignment and spatial calibration. Other upgrades included better bracing of flight tubes and viewing optics as well as a redesigned beam dump. An overview of these improvements will be presented. Supported by US DOE Contracts DE-AC02-09CH11466 and DE-AC52-07NA27344.

  4. Commercial-off-the-Shelf Vehicles for Towed Array Magnetometry

    DTIC Science & Technology

    2009-09-01

    dump bed on the back, has upright seating for two adults, has the seats oriented side-by-side, and has a steering wheel and brake and accelerator... pedals like a car. By way of example, a ubiquitous side-by-side UTV is the John Deere Gator. The objective of this project was to test a number of...different angle , and one set of biases will not be able to take out all of the streaks. This raises the second issue. Because the bidirectional

  5. Excited state proton transfer in strongly enhanced GFP (sGFP2).

    PubMed

    van Oort, Bart; ter Veer, Mirelle J T; Groot, Marie Louise; van Stokkum, Ivo H M

    2012-07-07

    Proton transfer is an elementary process in biology. Green fluorescent protein (GFP) has served as an important model system to elucidate the mechanistic details of this reaction, because in GFP proton transfer can be induced by light absorption. We have used pump-dump-probe spectroscopy to study how proton transfer through the 'proton-wire' around the chromophore is affected by a combination of mutations in a modern GFP variety (sGFP2). The results indicate that in H(2)O, after absorption of a photon, a proton is transferred (A* → I*) in 5 ps, and back-transferred from a ground state intermediate (I → A) in 0.3 ns, similar to time constants found with GFPuv, although sGFP2 shows less heterogeneous proton transfer. This suggests that the mutations left the proton-transfer largely unchanged, indicating the robustness of the proton-wire. We used pump-dump-probe spectroscopy in combination with target analysis to probe suitability of the sGFP2 fluorophore for super-resolution microscopy.

  6. Neutron Energy and Time-of-flight Spectra Behind the Lateral Shield of a High Energy Electron Accelerator Beam Dump, Part II: Monte Carlo Simulations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Roesler, Stefan

    2002-09-19

    Energy spectra of high-energy neutrons and neutron time-of-flight spectra were calculated for the setup of experiment T-454 performed with a NE213 liquid scintillator at the Final Focus Test Beam (FFTB) facility at the Stanford Linear Accelerator Center. The neutrons were created by the interaction a 28.7 GeV electron beam in the aluminum beam dump of the FFTB which is housed inside a thick steel and concrete shielding. In order to determine the attenuation length of high-energy neutrons additional concrete shielding of various thicknesses was placed outside the existing shielding. The calculations were performed using the FLUKA interaction and transport code.more » The energy and time-of-flight were recorded for the location of the detector allowing a detailed comparison with the experimental data. A generally good description of the data is achieved adding confidence to the use of FLUKA for the design of shielding for high-energy electron accelerators.« less

  7. Femtosecond Pump-Push-Probe and Pump-Dump-Probe Spectroscopy of Conjugated Polymers: New Insight and Opportunities.

    PubMed

    Kee, Tak W

    2014-09-18

    Conjugated polymers are an important class of soft materials that exhibit a wide range of applications. The excited states of conjugated polymers, often referred to as excitons, can either deactivate to yield the ground state or dissociate in the presence of an electron acceptor to form charge carriers. These interesting properties give rise to their luminescence and the photovoltaic effect. Femtosecond spectroscopy is a crucial tool for studying conjugated polymers. Recently, more elaborate experimental configurations utilizing three optical pulses, namely, pump-push-probe and pump-dump-probe, have been employed to investigate the properties of excitons and charge-transfer states of conjugated polymers. These studies have revealed new insight into femtosecond torsional relaxation and detrapping of bound charge pairs of conjugated polymers. This Perspective highlights (1) the recent achievements by several research groups in using pump-push-probe and pump-dump-probe spectroscopy to study conjugated polymers and (2) future opportunities and potential challenges of these techniques.

  8. Thermal Catalytic Oxidation of Airborne Contaminants by a Reactor Using Ultra-Short Channel Length, Monolithic Catalyst Substrates

    NASA Technical Reports Server (NTRS)

    Perry, J. L.; Tomes, K. M.; Tatara, J. D.

    2005-01-01

    Contaminated air, whether in a crewed spacecraft cabin or terrestrial work and living spaces, is a pervasive problem affecting human health, performance, and well being. The need for highly effective, economical air quality processes spans a wide range of terrestrial and space flight applications. Typically, air quality control processes rely on absorption-based processes. Most industrial packed-bed adsorption processes use activated carbon. Once saturated, the carbon is either dumped or regenerated. In either case, the dumped carbon and concentrated waste streams constitute a hazardous waste that must be handled safely while minimizing environmental impact. Thermal catalytic oxidation processes designed to address waste handling issues are moving to the forefront of cleaner air quality control and process gas decontamination processes. Careful consideration in designing the catalyst substrate and reactor can lead to more complete contaminant destruction and poisoning resistance. Maintenance improvements leading to reduced waste handling and process downtime can also be realized. Performance of a prototype thermal catalytic reaction based on ultra-short waste channel, monolith catalyst substrate design, under a variety of process flow and contaminant loading conditions, is discussed.

  9. Profiling of back-scattered electrons in opposed magnetic field of a Twin Electron Beam Gun

    NASA Astrophysics Data System (ADS)

    Sethi, S.; Gupta, Anchal; Dileep Kumar, V.; Mukherjee, Jaya; Gantayet, L. M.

    2012-11-01

    Electron gun is extensively used in material processing, physical vapour deposition and atomic vapour based laser processes. In these processes where the electron beam is incident on the substrate, a significant fraction of electron beam gets back-scattered from the target surface. The trajectory of this back scattered electron beam depends on the magnetic field in the vicinity. The fraction of back-scattered depends on the atomic number of the target metal and can be as high as ~40% of the incident beam current. These back-scattered electrons can cause undesired hot spots and also affect the overall process. Hence, the study of the trajectory of these back-scattered electrons is important. This paper provides the details of experimentally mapped back-scattered electrons of a 2×20kW Twin Electron Beam Gun (TEBG) in opposed magnetic field i.e. with these guns placed at 180° to each other.

  10. On the enhancement of the back-to-back two-electron-one photon ionization in molecules

    NASA Astrophysics Data System (ADS)

    Amusia, Miron; Drukarev, Eugene

    2014-05-01

    Recently, the long ago predicted quasi-free mechanism of two-electron photoionization was detected already at relatively low energy photoionization in He. It was observed that some pairs of electrons are leaving the target atom back-to-back, i.e. in opposite direction with almost the same energy. They have opposite spin directions. The cross-section of this process depends upon the probability for a pair of electrons to be close to each other before meeting the incoming photon. Such probability is greatly enhanced in molecules with covalent bonding, like H2. In this and similar molecules the electrons spend an essential part of time being between nuclei and thus screening them from each other. We demonstrate that indeed the back-to-back contribution is much bigger in H2 than in He. We analyze qualitatively some other situations that lead to relative growth of back-to-back contribution. Atoms with electrons with bigger principal quantum numbers have bigger back-to-back contributions. An external pressure applied to molecules forces electrons to be closer to each other. As a result for them the back-to-back contribution can be controllable enhanced.

  11. Risk Assessment of Heavy Metals in Abandoned Mine Lands as Signifcant Contamination Problem in Romania

    NASA Astrophysics Data System (ADS)

    Horvath, E.; Jordan, G.; Fugedi, U.; Bartha, A.; Kuti, L.; Heltai, G.; Kalmar, J.; Waldmann, I.; Napradean, I.; Damian, G.

    2009-04-01

    INTRODUCTION Wide-spread environmental contamination associated with historic mining in Europe has triggered social responses to improve related environmental legislation, the environmental assessment and management methods for the mining industry. Pollution by acid mine drainage (AMD) from ore and coal mining is the outstanding and most important source of mining-induced environmental pollution. Younger et al. (2002) estimates that watercourses polluted by coal mine drainage could be in the order of 2,000 to 3,000 km, and 1,000 to 1,500 km polluted by metal mine discharges for the EU 15 Member States (Younger et al. 2002). Significance of contamination risk posed by mining is also highlighted by mine accidents such as those in Baia Mare, Romania in 2002 and in Aznalcollar, Spain in 1999 (Jordan and D'Alessandro 2004). The new EU Mine Waste Directive (Directive 2006/21/EC) requires the risk-based inventory of abandoned mines in the EU. The cost-effective implementation of the inventory is especially demanding in countries with extensive historic mining and great number of abandoned mine sites, like Romania. The problem is further complicated in areas with trans-boundary effects. The objective of this investigation to carry out the risk-based contamination assessment of a mine site with possible trans-boundary effects in Romania. Assessment follows the source-pathway-receptor chain with a special attention to heavy metal leaching from waste dumps as sources and to transport modelling along surface water pathways. STUDY AREA In this paper the Baiut mine catchment located in the Gutai Mts., Romania, close to the Hungarian border is studied. The polymetallic deposites in the Tertiary Inner-Carpathian Volcanic Arc are exposed by a series of abandoned Zn and Pb mines first operated in the 14th century. Elevation in the high relief catchment ranges from 449m to 1044m. Geology is characterised by andesites hosting the ore deposits and paleogene sediments dominating at the lower topographic elevations. Several mine adits, waste rock dumps are located along the main stream and a large tailings dump is found next to village Baiut just above the receiving floodplain. Predominant land cover is coniferous and mixed forests with agricultural lands on the downstream floodplain. METHODS Six samples at vaious depths were collected from the two major waste rock dumps in the headwater area, and the large tailings dump was also sampled for heavy metal source characterisation. 11 stream sediment samples were collected along the main surface water contamination transport pathway, and a further 11 soil samples were collected in 2 boreholes in the receptor floodplain in October 2008. Besides background stream sediment samples, samples from the exposed rock formations were also collected in order to capture natural background geochemistry in the studied mineralised area. The collected waste rock, stream sediment, soil and rock samples are analysed for total chemical composition (major elements and heavy metals) by ICP-MS spectroscopy, and XRD is used for the determination of mineralogical composition. Rock sample mineralogy is further investigated in thin-sections by petrological microscopy. According to EU legislation expectations, a special emphasis is taken on the determination of metal mobility from the waste rock dumps and various leaching tests are performed and compared including US EPA, USGS and ISO methods. A simple cathcment-based distributed sediment transport model (Jordan et al, 2005; Jordan et al. 2005, 2008) is used to decribe the pathways and quantities of particle-bound contamination. RESULTS AND CONCLUSIONS Results show that (1) sediments are an efficient means for the preliminary inventory of mine contamination as a preparation for the more detailed hydrological sampling and assessment, and (2) the risk-based contamination assessment of mining sites often located in diverse geological, hydrological and landcover environment requires careful and successive sampling design and a tiered assessment approach. Leaching tests are shown cost-efficient and informative methods for source (hazard) characterisation. REFERENCES Directive 2006/21/EC the European Parliament and of the Council on the management of waste from extractive industries and amending Directive 2004/35/EC. Commission of the European Communities, Brussels. Jordan G. and D'Alessandro M. (eds) (2004) Mining, Mining Waste and Related Environmental Issues: Problems and Solutions in the Central and Eastern European Candidate Countries. Joint Research Centre of the European Commission, Ispra. LB-NA-20868-EN-C. Jordan G., van Rompaey A., Szilassi P., Csillag G., Mannaerts C. and Woldai T. (2005) Historical land use changes and their impact on sediment fluxes in the Balaton basin (Hungary). Agriculture, Ecosystems and Environment, 108, 119-133. Jordan G., van Rompaey A., Somody A., Fügedi U., Bats M. and Farsang A. (2008) Spatial Modelling of Contamination in a Catchment Area Impacted by Mining: a Case Study for the Recsk Copper Mines, Hungary. Journal of Land Contamination and Reclamation (in press). Younger P.L., Banwart S.A., Hedin R.S. (2002) Mine water. Hydrology, pollution, remediation. Kluwer Academic Publishers, Dodrecht.

  12. An FPGA-based data acquisition system for directional dark matter detection

    NASA Astrophysics Data System (ADS)

    Yang, Chen; Nicoloff, Catherine; Sanaullah, Ahmed; Sridhar, Arvind; Herbordt, Martin; Battat, James; Battat Lab at Wellesley College Team; CAAD Lab at Boston University Team

    2017-01-01

    Directional dark matter detection is a powerful tool in the search for dark matter. Low-pressure gas TPCs are commonly used for directional detection, and dark-matter-induced recoils are mm long. These tracks can be reconstructed by micropatterned readouts. Because large detector volumes are needed, a cost-effective data acquisition system capable of scaling to large channel counts (105 or 106) is required. The Directional Recoil Identification From Tracks (DRIFT) collaboration has pioneered the use of TPCs for directional detection. We employ a negative ion gas with drift speed comparable to the electron drift speed in liquid argon (LAr). We aim to use electronics developed for million-channel readouts in large LAr neutrino detectors. We have built a prototype Micromegas-based directional detector with 103 channels. A FPGA-based back-end system (BE) receives a 12 Gbps data stream from eight ASIC-based front-end boards (FE), each with 128 detector channels. The BE buffers 3 μs of pretrigger data for all channels in DRAM, and streams triggered data to a host PC. We will describe the system architecture and present preliminary measurements from the DAQ. We acknowledge the support of the Research Corporation for Science Advancement, the NSF and the Massachusetts Space Grant Consortium.

  13. Assessment and quantification of plastics waste generation in major 60 cities of India.

    PubMed

    Nalini, R; Srinivasulu, B; Shit, Subhas C; Nigam, Suneel Kumar; Akolkar, A B; Dwivedfi, R K

    2013-04-01

    Polymers or plastics materials registered rapid growth in 1970s, 1980s and 1990s at the rate of 2-2.5 times the GDP growth in India. The demand for plastic raw material got more than doubled from 3.3 Million Metric Ton to 6.8 Million Metric Tons in 2010 attributed mainly to rapid urbanization, spread of retail chains, plastics based packaging from grocery to food and vegetable products to cosmetics and consumer items. Plastics packages have its merits over many of conventional materials in the related sector but unless they are collected back effectively after their use to go into recycling process, they become an eyesore in the stream of Municipal Solid Waste (MSW) due to high visibility. As the synthetic and conventional plastics are non-biodegradable in nature, these remain in the dump yards/ landfills for several years, if not collected properly. Due to non- biodegradability, plastics waste remains in the environment for several years, if not collected and disposing plastics wastes at landfills are unsafe since toxic chemicals leach out into the soil and as they contaminate soil and underground water quality. The municipal solid waste also increasing day-by-day due to the inefficient source collection, segregation and transmission of plastics waste for recycling and reusing. In order to find out the realistic plastics waste generation, a study on assessment and quantification of plastics waste has been carried out by CPCB in collaboration with CIPET on selected 60 major cities of India.

  14. 40 CFR 469.13 - Monitoring.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ELECTRICAL AND ELECTRONIC COMPONENTS POINT SOURCE CATEGORY Semiconductor Subcategory § 469.13 Monitoring. (a... with the permit limitation for total toxic organics (TTO), I certify that, to the best of my knowledge and belief, no dumping of concentrated toxic organics into the wastewaters has occurred since filing...

  15. The BDX experiment at Jefferson Laboratory

    NASA Astrophysics Data System (ADS)

    Celentano, Andrea

    2015-06-01

    The existence of MeV-GeV dark matter (DM) is theoretically well motivated but remarkably unexplored. The Beam Dump eXperiment (BDX) at Jefferson Laboratory aims to investigate this mass range. Dark matter particles will be detected trough scattering on a segmented, plastic scintillator detector placed downstream of the beam-dump at one of the high intensity JLab experimental Halls. The experiment will collect up to 1022 electrons-on-target (EOT) in a one-year period. For these conditions, BDX is sensitive to the DM-nucleon elastic scattering at the level of a thousand counts per year, and is only limited by cosmogenic backgrounds. The experiment is also sensitive to DM-electron elastic and inelastic scattering, at the level of 10 counts/year. The foreseen signal for these channels is an high-energy (> 100 MeV) electromagnetic shower, with almost no background. The experiment, has been presented in form of a Letter of Intent to the laboratory, receiving positive feedback, and is currently being designed.

  16. Streaming energetic electrons in earth's magnetotail - Evidence for substorm-associated magnetic reconnection

    NASA Technical Reports Server (NTRS)

    Bieber, J. W.; Stone, E. C.

    1980-01-01

    This letter reports the results of a systematic study of streaming greater than 200 keV electrons observed in the magnetotail with the Caltech Electron/Isotope Spectrometers aboard IMP-7 and IMP-8. A clear statistical association of streaming events with southward magnetic fields, often of steep inclination, and with substorms as evidenced by the AE index is demonstrated. These results support the interpretation that streaming energetic electrons are indicative of substorm-associated magnetic reconnection in the near-earth plasma sheet.

  17. Looking Back at a Job Well Done

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This image shows the view from Deep Impact's flyby spacecraft as it turned back to look at comet Tempel 1. Fifty minutes earlier, the spacecraft's probe was run over by the comet. That collision kicked up plumes of ejected material, seen here streaming away from the back side of the comet. This image was taken by the flyby craft's high-resolution camera.

  18. Real-time observation of intramolecular proton transfer in the electronic ground state of chloromalonaldehyde: an ab initio study of time-resolved photoelectron spectra.

    PubMed

    do N Varella, Márcio T; Arasaki, Yasuki; Ushiyama, Hiroshi; Takatsuka, Kazuo; Wang, Kwanghsi; McKoy, Vincent

    2007-02-07

    The authors report on studies of time-resolved photoelectron spectra of intramolecular proton transfer in the ground state of chloromalonaldehyde, employing ab initio photoionization matrix elements and effective potential surfaces of reduced dimensionality, wherein the couplings of proton motion to the other molecular vibrational modes are embedded by averaging over classical trajectories. In the simulations, population is transferred from the vibrational ground state to vibrationally hot wave packets by pumping to an excited electronic state and dumping with a time-delayed pulse. These pump-dump-probe simulations demonstrate that the time-resolved photoelectron spectra track proton transfer in the electronic ground state well and, furthermore, that the geometry dependence of the matrix elements enhances the tracking compared with signals obtained with the Condon approximation. Photoelectron kinetic energy distributions arising from wave packets localized in different basins are also distinguishable and could be understood, as expected, on the basis of the strength of the optical couplings in different regions of the ground state potential surface and the Franck-Condon overlaps of the ground state wave packets with the vibrational eigenstates of the ion potential surface.

  19. Variable energy, high flux, ground-state atomic oxygen source

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Orient, Otto J. (Inventor)

    1987-01-01

    A variable energy, high flux atomic oxygen source is described which is comprised of a means for producing a high density beam of molecules which will emit O(-) ions when bombarded with electrons; a means of producing a high current stream of electrons at a low energy level passing through the high density beam of molecules to produce a combined stream of electrons and O(-) ions; means for accelerating the combined stream to a desired energy level; means for producing an intense magnetic field to confine the electrons and O(-) ions; means for directing a multiple pass laser beam through the combined stream to strip off the excess electrons from a plurality of the O(-) ions to produce ground-state O atoms within the combined stream; electrostatic deflection means for deflecting the path of the O(-) ions and the electrons in the combined stream; and, means for stopping the O(-) ions and the electrons and for allowing only the ground-state O atoms to continue as the source of the atoms of interest. The method and apparatus are also adaptable for producing other ground-state atoms and/or molecules.

  20. TERMINAL ELECTRON ACCEPTING PROCESSES IN THE ALLUVIAL SEDIMENTS OF A HEADWATER STREAM

    EPA Science Inventory

    Chemical fluxes between catchments and streams are influenced by biochemical processes in the groundwater-stream water (GW-SW) ecotone, the interface between stream surface water and groundwater. Terminal electron accepting processes (TEAPs) that are utilized in respiration of ...

  1. 40 CFR 227.14 - Criteria for evaluating the need for ocean dumping and alternatives to ocean dumping.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ocean dumping and alternatives to ocean dumping. 227.14 Section 227.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Need for Ocean Dumping § 227.14 Criteria for evaluating the need for ocean...

  2. 40 CFR 227.14 - Criteria for evaluating the need for ocean dumping and alternatives to ocean dumping.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ocean dumping and alternatives to ocean dumping. 227.14 Section 227.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Need for Ocean Dumping § 227.14 Criteria for evaluating the need for ocean...

  3. 40 CFR 227.14 - Criteria for evaluating the need for ocean dumping and alternatives to ocean dumping.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ocean dumping and alternatives to ocean dumping. 227.14 Section 227.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Need for Ocean Dumping § 227.14 Criteria for evaluating the need for ocean...

  4. 40 CFR 227.14 - Criteria for evaluating the need for ocean dumping and alternatives to ocean dumping.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ocean dumping and alternatives to ocean dumping. 227.14 Section 227.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Need for Ocean Dumping § 227.14 Criteria for evaluating the need for ocean...

  5. 40 CFR 227.14 - Criteria for evaluating the need for ocean dumping and alternatives to ocean dumping.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ocean dumping and alternatives to ocean dumping. 227.14 Section 227.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Need for Ocean Dumping § 227.14 Criteria for evaluating the need for ocean...

  6. Factors influencing load-haul-dump operator line of sight in underground mining.

    PubMed

    Eger, Tammy; Salmoni, Alan; Whissell, Robert

    2004-03-01

    The inability of load-haul-dump (LHD) equipment operators to see people, objects or hazards around the LHD machine they drive is a causal factor in a number of serious accidents. Line of sight evaluations were conducted on 11 different LHD models. Results indicated blind spots were caused by cab posts, and vehicles lights and light brackets. Line of sight impairments were caused by wheel well covers, buckets, fire extinguisher, light posts, radiator covers, booms, radio remote boxes, elevated engine profiles and air intake cylinders. These results were supported by questionnaires completed by 130 LHD operators. The operators indicated the bucket, lights and light brackets, boom and cab impaired line of sight. Line of sight testing and LHD operator feedback indicated line of sight to the right front corner and back right corner were typically worse than line of sight to the front left side of the vehicle. Results of this study have been used to conduct awareness campaigns within the Ontario mining industry and to suggest vehicle design modifications to LHD manufacturers.

  7. Method for eliminating artifacts in CCD imagers

    DOEpatents

    Turko, B.T.; Yates, G.J.

    1992-06-09

    An electronic method for eliminating artifacts in a video camera employing a charge coupled device (CCD) as an image sensor is disclosed. The method comprises the step of initializing the camera prior to normal read out and includes a first dump cycle period for transferring radiation generated charge into the horizontal register while the decaying image on the phosphor being imaged is being integrated in the photosites, and a second dump cycle period, occurring after the phosphor image has decayed, for rapidly dumping unwanted smear charge which has been generated in the vertical registers. Image charge is then transferred from the photosites and to the vertical registers and read out in conventional fashion. The inventive method allows the video camera to be used in environments having high ionizing radiation content, and to capture images of events of very short duration and occurring either within or outside the normal visual wavelength spectrum. Resultant images are free from ghost, smear and smear phenomena caused by insufficient opacity of the registers and, and are also free from random damage caused by ionization charges which exceed the charge limit capacity of the photosites. 3 figs.

  8. Tunneling induced electron transfer between separated protons

    NASA Astrophysics Data System (ADS)

    Vindel-Zandbergen, Patricia; Meier, Christoph; Sola, Ignacio R.

    2018-04-01

    We study electron transfer between two separated protons using local control theory. In this symmetric system one can favour a slow transfer by biasing the algorithm, achieving high efficiencies for fixed nuclei. The solution can be parametrized using a sequence of a pump followed by a dump pulse that lead to tunneling-induced electron transfer. Finally, we study the effect of the nuclear kinetic energy on the efficiency. Even in the absence of relative motion between the protons, the spreading of the nuclear wave function is enough to reduce the yield of electronic transfer to less than one half.

  9. Quantum coherent π-electron rotations in a non-planar chiral molecule induced by using a linearly polarized UV laser pulse

    NASA Astrophysics Data System (ADS)

    Mineo, Hirobumi; Fujimura, Yuichi

    2015-06-01

    We propose an ultrafast quantum switching method of π-electron rotations, which are switched among four rotational patterns in a nonplanar chiral aromatic molecule (P)-2,2’- biphenol and perform the sequential switching among four rotational patterns which are performed by the overlapped pump-dump laser pulses. Coherent π-electron dynamics are generated by applying the linearly polarized UV pulse laser to create a pair of coherent quasidegenerated excited states. We also plot the time-dependent π-electron ring current, and discussed ring current transfer between two aromatic rings.

  10. A transverse separate-spin-evolution streaming instability

    NASA Astrophysics Data System (ADS)

    Iqbal, Z.; Andreev, Pavel A.; Murtaza, G.

    2018-05-01

    By using the separate spin evolution quantum hydrodynamical model, the instability of transverse mode due to electron streaming in a partially spin polarized magnetized degenerate plasma is studied. The electron spin polarization gives birth to a new spin-dependent wave (i.e., separate spin evolution streaming driven ordinary wave) in the real wave spectrum. It is shown that the spin polarization and streaming speed significantly affect the frequency of this new mode. Analyzing growth rate, it is found that the electron spin effects reduce the growth rate and shift the threshold of instability as well as its termination point towards higher values. Additionally, how the other parameters like electron streaming and Fermi pressure influence the growth rate is also investigated. Current study can help towards better understanding of the existence of new waves and streaming instability in the astrophysical plasmas.

  11. Modeling of Water Injection into a Vacuum

    NASA Technical Reports Server (NTRS)

    Alred, John W.; Smith, Nicole L.; Wang, K. C.; Lumpkin, Forrest E.; Fitzgerald, Steven M.

    1997-01-01

    A loosely coupled two-phase vacuum water plume model has been developed. This model consists of a source flow model to describe the expansion of water vapor, and the Lagrangian equations of motion for particle trajectories. Gas/Particle interaction is modeled through the drag force induced by the relative velocities. Particles are assumed traveling along streamlines. The equations of motion are integrated to obtain particle velocity along the streamline. This model has been used to predict the mass flux in a 5 meter radius hemispherical domain resulting from the burst of a water jet of 1.5 mm in diameter, mass flow rate of 24.2 g/s, and stagnation pressure of 21.0 psia, which is the nominal Orbiter water dump condition. The result is compared with an empirical water plume model deduced from a video image of the STS-29 water dump. To further improve the model, work has begun to numerically simulate the bubble formation and bursting present in a liquid stream injected into a vacuum. The technique of smoothed particle hydrodynamics was used to formulate this simulation. A status and results of the on-going effort are presented and compared to results from the literature.

  12. Learn about Ocean Dumping

    EPA Pesticide Factsheets

    Ocean dumping is regulated by the Marine Protection, Research and Sanctuaries Act (MPRSA). Learn about ocean dumping regulation including what materials can and cannot be dumped, the Ocean Dumping Management Program, and MPRSA history and accomplishments.

  13. Autonomous Laser-Powered Vehicle

    NASA Technical Reports Server (NTRS)

    Stone, William C. (Inventor); Hogan, Bartholomew P. (Inventor)

    2017-01-01

    An autonomous laser-powered vehicle designed to autonomously penetrate through ice caps of substantial (e.g., kilometers) thickness by melting a path ahead of the vehicle as it descends. A high powered laser beam is transmitted to the vehicle via an onboard bare fiber spooler. After the beam enters through the dispersion optics, the beam expands into a cavity. A radiation shield limits backscatter radiation from heating the optics. The expanded beam enters the heat exchanger and is reflected by a dispersion mirror. Forward-facing beveled circular grooves absorb the reflected radiant energy preventing the energy from being reflected back towards the optics. Microchannels along the inner circumference of the beam dump heat exchanger maximize heat transfer. Sufficient amount of fiber is wound on the fiber spooler to permit not only a descent but also to permit a sample return mission by inverting the vehicle and melting its way back to the surface.

  14. 40 CFR 221.5 - Processing fees.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... be charged in connection with each application for a permit for dumping in an existing dump site... with each application for a permit for dumping in a dump site other than a dump site designated in this...

  15. 40 CFR 221.5 - Processing fees.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... be charged in connection with each application for a permit for dumping in an existing dump site... with each application for a permit for dumping in a dump site other than a dump site designated in this...

  16. Environmental impact of coal ash on tributary streams and nearshore waters of Lake Erie. Quarterly reports, August 31 and November 30, 1975, combined. [Cd, Zn, Cu, Fe, Mn, Cr, Ca, K, Mg, Na, Pb, As, Se

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    The study of coal wastes in Chautauga County, New York was begun on June 1, 1975. The major effort to date has been made on the fly ash dump west of Dunkirk, N.Y. The following topics are covered: description of the site; invertebrate biology; selection of trace elements for study and methods of analysis; water analyses; analyses of invertebrates; literature search; physical chemistry of coal ash and the leaching process; and study of lake sediments.

  17. 49 CFR 176.97 - Prohibition of dump scows.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Prohibition of dump scows. 176.97 Section 176.97... Requirements for Barges § 176.97 Prohibition of dump scows. Dump scows are barges having cargo carrying compartments of the hopper type and fitted with a bottom dump or a side dump. This type of barge is prohibited...

  18. 49 CFR 176.97 - Prohibition of dump scows.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Prohibition of dump scows. 176.97 Section 176.97... Requirements for Barges § 176.97 Prohibition of dump scows. Dump scows are barges having cargo carrying compartments of the hopper type and fitted with a bottom dump or a side dump. This type of barge is prohibited...

  19. NASA in Silicon Valley Live - Episode 01 - We're Going Back to the Moon!

    NASA Image and Video Library

    2018-01-12

    We’ve launched a live video show on Twitch called NASA in Silicon Valley Live! This is our premiere episode streamed on Jan. 12. In it, we talk about going back to the Moon with NASA rock stars Jim Green and Greg Schmidt.

  20. Magnetically operated beam dump for dumping high power beams in a neutral beamline

    DOEpatents

    Dagenhart, W.K.

    1984-01-27

    It is an object of this invention to provide a beam dump system for a neutral beam generator which lowers the time-averaged power density of the beam dump impingement surface. Another object of this invention is to provide a beam dump system for a neutral particle beam based on reionization and subsequent magnetic beam position modulation of the beam onto a beam dump surface to lower the time-averaged power density of the beam dump ion impingement surface.

  1. Development of a methodology for electronic waste estimation: A material flow analysis-based SYE-Waste Model.

    PubMed

    Yedla, Sudhakar

    2016-01-01

    Improved living standards and the share of services sector to the economy in Asia, and the use of electronic equipment is on the rise and results in increased electronic waste generation. A peculiarity of electronic waste is that it has a 'significant' value even after its life time, and to add complication, even after its extended life in its 'dump' stage. Thus, in Indian situations, after its life time is over, the e-material changes hands more than once and finally ends up either in the hands of informal recyclers or in the store rooms of urban dwellings. This character makes it extremely difficult to estimate electronic waste generation. The present study attempts to develop a functional model based on a material flow analysis approach by considering all possible end uses of the material, its transformed goods finally arriving at disposal. It considers various degrees of uses derived of the e-goods regarding their primary use (life time), secondary use (first degree extension of life), third-hand use (second degree extension of life), donation, retention at the respective places (without discarding), fraction shifted to scrap vendor, and the components reaching the final dump site from various end points of use. This 'generic functional model' named SYE-Waste Model, developed based on a material flow analysis approach, can be used to derive 'obsolescence factors' for various degrees of usage of e-goods and also to make a comprehensive estimation of electronic waste in any city/country. © The Author(s) 2015.

  2. perf-dump

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gamblin, T.

    perf-dump is a library for dumping performance data in much the same way physics simulations dump checkpoints. It records per-process, per-timestep, per-phase, and per-thread performance counter data and dumps this large data periodically into an HDF5 data file.

  3. 40 CFR 63.496 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... methods of determining this quantity are production records, measurement of stream characteristics, and... HAP (or TOC, minus methane and ethane) emissions in all process vent streams and primary and secondary... heater. (B) Paragraph (b)(5)(iii) of this section is applicable, except that TOC (minus methane and...

  4. 40 CFR 63.496 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... methods of determining this quantity are production records, measurement of stream characteristics, and... HAP (or TOC, minus methane and ethane) emissions in all process vent streams and primary and secondary... heater. (B) Paragraph (b)(5)(iii) of this section is applicable, except that TOC (minus methane and...

  5. 40 CFR 63.496 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... methods of determining this quantity are production records, measurement of stream characteristics, and... HAP (or TOC, minus methane and ethane) emissions in all process vent streams and primary and secondary... heater. (B) Paragraph (b)(5)(iii) of this section is applicable, except that TOC (minus methane and...

  6. 40 CFR 63.496 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... methods of determining this quantity are production records, measurement of stream characteristics, and... HAP (or TOC, minus methane and ethane) emissions in all process vent streams and primary and secondary... heater. (B) Paragraph (b)(5)(iii) of this section is applicable, except that TOC (minus methane and...

  7. Analysis of the interaction of an electron beam with back surface field solar cells

    NASA Technical Reports Server (NTRS)

    Von Roos, O.; Luke, K. L.

    1983-01-01

    In this paper the short circuit current Isc induced by the electron beam of a scanning electron microscope in a back surface field solar cell will be determined theoretically. It will be shown that, in a configuration used previously for solar cells with an ohmic back surface, the Isc gives a convenient means for estimating the back surface recombination velocities and thus the quality of back surface field cells. Numerical data will be presented applicable to a point source model for the electron-hole pair generation.

  8. Live video monitoring robot controlled by web over internet

    NASA Astrophysics Data System (ADS)

    Lokanath, M.; Akhil Sai, Guruju

    2017-11-01

    Future is all about robots, robot can perform tasks where humans cannot, Robots have huge applications in military and industrial area for lifting heavy weights, for accurate placements, for repeating the same task number of times, where human are not efficient. Generally robot is a mix of electronic, electrical and mechanical engineering and can do the tasks automatically on its own or under the supervision of humans. The camera is the eye for robot, call as robovision helps in monitoring security system and also can reach into the places where the human eye cannot reach. This paper presents about developing a live video streaming robot controlled from the website. We designed the web, controlling for the robot to move left, right, front and back while streaming video. As we move to the smart environment or IoT (Internet of Things) by smart devices the system we developed here connects over the internet and can be operated with smart mobile phone using a web browser. The Raspberry Pi model B chip acts as heart for this system robot, the sufficient motors, surveillance camera R pi 2 are connected to Raspberry pi.

  9. Ion Streaming Instabilities in Pair Ion Plasma and Localized Structure with Non-Thermal Electrons

    NASA Astrophysics Data System (ADS)

    Nasir Khattak, M.; Mushtaq, A.; Qamar, A.

    2015-12-01

    Pair ion plasma with a fraction of non-thermal electrons is considered. We investigate the effects of the streaming motion of ions on linear and nonlinear properties of unmagnetized, collisionless plasma by using the fluid model. A dispersion relation is derived, and the growth rate of streaming instabilities with effect of streaming motion of ions and non-thermal electrons is calculated. A qausi-potential approach is adopted to study the characteristics of ion acoustic solitons. An energy integral equation involving Sagdeev potential is derived during this process. The presence of the streaming term in the energy integral equation affects the structure of the solitary waves significantly along with non-thermal electrons. Possible application of the work to the space and laboratory plasmas are highlighted.

  10. An investigation of used electronics return flows: a data-driven approach to capture and predict consumers storage and utilization behavior.

    PubMed

    Sabbaghi, Mostafa; Esmaeilian, Behzad; Raihanian Mashhadi, Ardeshir; Behdad, Sara; Cade, Willie

    2015-02-01

    Consumers often have a tendency to store their used, old or un-functional electronics for a period of time before they discard them and return them back to the waste stream. This behavior increases the obsolescence rate of used still-functional products leading to lower profitability that could be resulted out of End-of-Use (EOU) treatments such as reuse, upgrade, and refurbishment. These types of behaviors are influenced by several product and consumer-related factors such as consumers' traits and lifestyles, technology evolution, product design features, product market value, and pro-environmental stimuli. Better understanding of different groups of consumers, their utilization and storage behavior and the connection of these behaviors with product design features helps Original Equipment Manufacturers (OEMs) and recycling and recovery industry to better overcome the challenges resulting from the undesirable storage of used products. This paper aims at providing insightful statistical analysis of Electronic Waste (e-waste) dynamic nature by studying the effects of design characteristics, brand and consumer type on the electronics usage time and end of use time-in-storage. A database consisting of 10,063 Hard Disk Drives (HDD) of used personal computers returned back to a remanufacturing facility located in Chicago, IL, USA during 2011-2013 has been selected as the base for this study. The results show that commercial consumers have stored computers more than household consumers regardless of brand and capacity factors. Moreover, a heterogeneous storage behavior is observed for different brands of HDDs regardless of capacity and consumer type factors. Finally, the storage behavior trends are projected for short-time forecasting and the storage times are precisely predicted by applying machine learning methods. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Polychlorinated Biphenyls Water Pollution along the River Nile, Egypt

    PubMed Central

    Megahed, Ayman Mohamed; Dahshan, Hesham; Abd-El-Kader, Mahdy A.; Abd-Elall, Amr Mohamed Mohamed; Elbana, Mariam Hassan; Nabawy, Ehab; Mahmoud, Hend A.

    2015-01-01

    Ten polychlorinated biphenyl (PCB) congeners were determined in water samples collected along the River Nile using gas chromatography-electron capture detector (GC-ECD). PCB concentrations ranged from 14 to 20 μg/L, which were higher than those reported in previous studies, indicating serious PCB pollution in the River Nile. PCB congener profiles varied depending on the sampling sties. PCB-138 was the predominant congener accounting for more than 18% of total PCBs. The composition of PCB congeners in the water revealed that highly chlorinated PCB technical mixtures such as Aroclor 1254 was the main PCB production historically used in Egypt. An increasing trend in PCB levels from the upper stream to the Nile estuaries was observed. The calculated flux of PCBs indicated that 6.8 tons of PCBs is dumped into the Mediterranean Sea each year from the River Nile. The hazard quotients and carcinogenic risk caused by PCB pollution in the River Nile were above the acceptable level indicating that PCBs in the River Nile water pose adverse health effects for all age groups. Our findings revealed that PCBs possess a serious risk to the Egyptian population that depends mainly on the River Nile as a source of water. Thus, stricter legislation and regulatory controls should be applied to reduce the risk of PCBs in Egypt. PMID:26798844

  12. Multipulse spectroscopy on the wild-type and YM210W Bacterial Reaction Centre uncovers a new intermediate state in the special pair excited state

    NASA Astrophysics Data System (ADS)

    Cohen Stuart, T. A.; van Grondelle, R.

    2009-06-01

    The Bacterial Reaction Centre (BRC) has a complex electronic excited state, P ∗, that evolves into subsequent charge separated product states P +H - and P +B -. Pump-dump-probe spectroscopy on the wild-type BRC and on YM210W, a mutant with a stabilized, long-lived P ∗ excited state, has uncovered a new charge-separated state in both BRC's. When P ∗ is dumped, a fraction of its population is transferred to this state that has a strong Stark shift in the accessory bacteriochlorophyll (B M) region which serves as a signature for P + and a lifetime highly comparable to the slow phase of P ∗ decay. This lead us propose this intermediate to be P +/P -.

  13. Search for tau-neutrino interactions in the BEBC beam dump experiment

    NASA Astrophysics Data System (ADS)

    Talebzadeh, M.; Guy, J.; Venus, W.; Aderholz, M.; Barnham, K. W. J.; Bostock, P.; Clayton, E. F.; Cooper-Sarkar, A. M.; Faccini-Turluer, M. L.; Grässler, H.; Hultquist, K.; Hulth, P. O.; Kreutzmann, H.; Krstic, J.; Miller, D. B.; Mobayyen, M. M.; Myatt, G.; Nellen, B.; Parker, M. A.; Schmitz, N.; Sewell, S.; Simopoulou, E.; Vayaki, A.; Vignaud, D.; Wachsmuth, H.; Wittek, W.; Wünsch, B.; BEBC WA66 Collaboration

    A novel and efficient kinematic method is used to estimate the number of ντ charged current interactions with Eν > 20 GeV in the BEBC beam dump experiment. The result, -14±12 ντ events, is consistent with zero. The ratio of D s to D meson production in 400 GeV proton interactions in copper is estimated to be below 0.65 at 90% c.l. The oscillation probability P( νe→ ντ) averaged over the electron-(anti)neutrino spectrum is found to be below 18%. The hypothesis that νe and ντ are identical is excluded by about 6 standard deviations. A remarkable event is described: it contains a muon, a high pT photon and a high pT hadron.

  14. Use of a radial self-field diode geometry for intense pulsed ion beam generation at 6 MeV on Hermes III

    DOE PAGES

    Renk, Timothy Jerome; Harper-Slaboszewicz, Victor Jozef; Mikkelson, Kenneth A.; ...

    2014-12-15

    We investigate the generation of intense pulsed focused ion beams at the 6 MeV level using an inductive voltage adder (IVA) pulsed-power generator, which employs a magnetically insulated transmission line (MITL). Such IVA machines typical run at an impedance of few tens of Ohms. Previous successful intense ion beam generation experiments have often featured an “axial” pinch-reflex ion diode (i.e., with an axial anode-cathode gap) and operated on a conventional Marx generator/water line driver with an impedance of a few Ohms and no need for an MITL. The goals of these experiments are to develop a pinch-reflex ion diode geometrymore » that has an impedance to efficiently match to an IVA, produces a reasonably high ion current fraction, captures the vacuum electron current flowing forward in the MITL, and focuses the resulting ion beam to small spot size. Furthermore, a new “radial” pinch-reflex ion diode (i.e., with a radial anode-cathode gap) is found to best demonstrate these properties. Operation in both positive and negative polarities was undertaken, although the negative polarity experiments are emphasized. Particle-in-cell (PIC) simulations are consistent with experimental results indicating that, for diode impedances less than the self-limited impedance of the MITL, almost all of the forward-going IVA vacuum electron flow current is incorporated into the diode current. PIC results also provide understanding of the diode-impedance and ion-focusing properties of the diode. Additionally, a substantial high-energy ion population is also identified propagating in the “reverse” direction, i.e., from the back side of the anode foil in the electron beam dump.« less

  15. Use of a radial self-field diode geometry for intense pulsed ion beam generation at 6 MeV on Hermes III

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Renk, T. J., E-mail: tjrenk@sandia.gov; Harper-Slaboszewicz, V.; Mikkelson, K. A.

    2014-12-15

    We investigate the generation of intense pulsed focused ion beams at the 6 MeV level using an inductive voltage adder (IVA) pulsed-power generator, which employs a magnetically insulated transmission line (MITL). Such IVA machines typical run at an impedance of few tens of Ohms. Previous successful intense ion beam generation experiments have often featured an “axial” pinch-reflex ion diode (i.e., with an axial anode-cathode gap) and operated on a conventional Marx generator/water line driver with an impedance of a few Ohms and no need for an MITL. The goals of these experiments are to develop a pinch-reflex ion diode geometry thatmore » has an impedance to efficiently match to an IVA, produces a reasonably high ion current fraction, captures the vacuum electron current flowing forward in the MITL, and focuses the resulting ion beam to small spot size. A new “radial” pinch-reflex ion diode (i.e., with a radial anode-cathode gap) is found to best demonstrate these properties. Operation in both positive and negative polarities was undertaken, although the negative polarity experiments are emphasized. Particle-in-cell (PIC) simulations are consistent with experimental results indicating that, for diode impedances less than the self-limited impedance of the MITL, almost all of the forward-going IVA vacuum electron flow current is incorporated into the diode current. PIC results also provide understanding of the diode-impedance and ion-focusing properties of the diode. In addition, a substantial high-energy ion population is also identified propagating in the “reverse” direction, i.e., from the back side of the anode foil in the electron beam dump.« less

  16. A neutron diagnostic for high current deuterium beams.

    PubMed

    Rebai, M; Cavenago, M; Croci, G; Dalla Palma, M; Gervasini, G; Ghezzi, F; Grosso, G; Murtas, F; Pasqualotto, R; Cippo, E Perelli; Tardocchi, M; Tollin, M; Gorini, G

    2012-02-01

    A neutron diagnostic for high current deuterium beams is proposed for installation on the spectral shear interferometry for direct electric field reconstruction (SPIDER, Source for Production of Ion of Deuterium Extracted from RF plasma) test beam facility. The proposed detection system is called Close-contact Neutron Emission Surface Mapping (CNESM). The diagnostic aims at providing the map of the neutron emission on the beam dump surface by placing a detector in close contact, right behind the dump. CNESM uses gas electron multiplier detectors equipped with a cathode that also serves as neutron-proton converter foil. The cathode is made of a thin polythene film and an aluminium film; it is designed for detection of neutrons of energy >2.2 MeV with an incidence angle < 45°. CNESM was designed on the basis of simulations of the different steps from the deuteron beam interaction with the beam dump to the neutron detection in the nGEM. Neutron scattering was simulated with the MCNPX code. CNESM on SPIDER is a first step towards the application of this diagnostic technique to the MITICA beam test facility, where it will be used to resolve the horizontal profile of the beam intensity.

  17. Method for eliminating artifacts in CCD imagers

    DOEpatents

    Turko, Bojan T.; Yates, George J.

    1992-01-01

    An electronic method for eliminating artifacts in a video camera (10) employing a charge coupled device (CCD) (12) as an image sensor. The method comprises the step of initializing the camera (10) prior to normal read out and includes a first dump cycle period (76) for transferring radiation generated charge into the horizontal register (28) while the decaying image on the phosphor (39) being imaged is being integrated in the photosites, and a second dump cycle period (78), occurring after the phosphor (39) image has decayed, for rapidly dumping unwanted smear charge which has been generated in the vertical registers (32). Image charge is then transferred from the photosites (36) and (38) to the vertical registers (32) and read out in conventional fashion. The inventive method allows the video camera (10) to be used in environments having high ionizing radiation content, and to capture images of events of very short duration and occurring either within or outside the normal visual wavelength spectrum. Resultant images are free from ghost, smear and smear phenomena caused by insufficient opacity of the registers (28) and (32), and are also free from random damage caused by ionization charges which exceed the charge limit capacity of the photosites (36) and (37).

  18. A neutron diagnostic for high current deuterium beams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rebai, M.; Perelli Cippo, E.; Cavenago, M.

    2012-02-15

    A neutron diagnostic for high current deuterium beams is proposed for installation on the spectral shear interferometry for direct electric field reconstruction (SPIDER, Source for Production of Ion of Deuterium Extracted from RF plasma) test beam facility. The proposed detection system is called Close-contact Neutron Emission Surface Mapping (CNESM). The diagnostic aims at providing the map of the neutron emission on the beam dump surface by placing a detector in close contact, right behind the dump. CNESM uses gas electron multiplier detectors equipped with a cathode that also serves as neutron-proton converter foil. The cathode is made of a thinmore » polythene film and an aluminium film; it is designed for detection of neutrons of energy >2.2 MeV with an incidence angle < 45 deg. CNESM was designed on the basis of simulations of the different steps from the deuteron beam interaction with the beam dump to the neutron detection in the nGEM. Neutron scattering was simulated with the MCNPX code. CNESM on SPIDER is a first step towards the application of this diagnostic technique to the MITICA beam test facility, where it will be used to resolve the horizontal profile of the beam intensity.« less

  19. 27 CFR 19.748 - Dump/batch records.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Dump/batch records. 19.748... OF THE TREASURY LIQUORS DISTILLED SPIRITS PLANTS Records and Reports Processing Account § 19.748 Dump/batch records. (a) Format of dump/batch records. Proprietor's dump/batch records shall contain, as...

  20. Multispectral analysis of ocean dumped materials

    NASA Technical Reports Server (NTRS)

    Johnson, R. W.

    1977-01-01

    Remotely sensed data were collected in conjunction with sea-truth measurements in three experiments in the New York Bight. Pollution features of primary interest were ocean dumped materials, such as sewage sludge and acid waste. Sewage-sludge and acid-waste plumes, including plumes from sewage sludge dumped by the 'line-dump' and 'spot-dump' methods, were located, identified, and mapped. Previously developed quantitative analysis techniques for determining quantitative distributions of materials in sewage sludge dumps were evaluated, along with multispectral analysis techniques developed to identify ocean dumped materials. Results of these experiments and the associated data analysis investigations are presented and discussed.

  1. Dump truck-related deaths in construction, 1992-2007.

    PubMed

    McCann, Michael; Cheng, Mei-Tai

    2012-05-01

    Dump trucks are universally used in construction and other industries to haul materials to the location and to remove waste materials. The source for dump truck-related fatality data was the Bureau of Labor Statistics Census of Fatal Occupational Injuries (CFOI) Research File. From 1992 to 2007, 829 construction workers were killed in dump truck-related incidents nationwide. Of those, 336 were dump truck operators with 215 deaths occurring in street and highway incidents. Another 343 deaths involved workers on foot, three-quarters struck by dump trucks. Sixty-four of the construction workers killed were maintaining dump trucks, 22 when caught between the truck frame and a falling dump truck bed. Of the 86 other deaths, 55 involved streets and highways. Recommendations include: (i) improving the reporting of seat belt usage in fatality reports; (ii) requiring use of seat belts; (iii) requiring the use of backup alarms, spotters, or other methods to alert dump truck operators to workers in their blind spots; (iv) prohibiting direct dumping at river banks and embankments; (v) using cameras or radar to enforce stopping at railway crossings; and (xi) enforcing worker safety practices (e.g., lockout/tagout procedures on elevated dump truck beds). Copyright © 2011 Wiley Periodicals, Inc.

  2. An investigation of used electronics return flows: A data-driven approach to capture and predict consumers storage and utilization behavior

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sabbaghi, Mostafa, E-mail: mostafas@buffalo.edu; Esmaeilian, Behzad, E-mail: b.esmaeilian@neu.edu; Raihanian Mashhadi, Ardeshir, E-mail: ardeshir@buffalo.edu

    Highlights: • We analyzed a data set of HDDs returned back to an e-waste collection site. • We studied factors that affect the storage behavior. • Consumer type, brand and size are among factors which affect the storage behavior. • Commercial consumers have stored computers more than household consumers. • Machine learning models were used to predict the storage behavior. - Abstract: Consumers often have a tendency to store their used, old or un-functional electronics for a period of time before they discard them and return them back to the waste stream. This behavior increases the obsolescence rate of usedmore » still-functional products leading to lower profitability that could be resulted out of End-of-Use (EOU) treatments such as reuse, upgrade, and refurbishment. These types of behaviors are influenced by several product and consumer-related factors such as consumers’ traits and lifestyles, technology evolution, product design features, product market value, and pro-environmental stimuli. Better understanding of different groups of consumers, their utilization and storage behavior and the connection of these behaviors with product design features helps Original Equipment Manufacturers (OEMs) and recycling and recovery industry to better overcome the challenges resulting from the undesirable storage of used products. This paper aims at providing insightful statistical analysis of Electronic Waste (e-waste) dynamic nature by studying the effects of design characteristics, brand and consumer type on the electronics usage time and end of use time-in-storage. A database consisting of 10,063 Hard Disk Drives (HDD) of used personal computers returned back to a remanufacturing facility located in Chicago, IL, USA during 2011–2013 has been selected as the base for this study. The results show that commercial consumers have stored computers more than household consumers regardless of brand and capacity factors. Moreover, a heterogeneous storage behavior is observed for different brands of HDDs regardless of capacity and consumer type factors. Finally, the storage behavior trends are projected for short-time forecasting and the storage times are precisely predicted by applying machine learning methods.« less

  3. Fast quench reactor method

    DOEpatents

    Detering, B.A.; Donaldson, A.D.; Fincke, J.R.; Kong, P.C.; Berry, R.A.

    1999-08-10

    A fast quench reaction includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a means of rapidly expanding a reactant stream, such as a restrictive convergent-divergent nozzle at its outlet end. Metal halide reactants are injected into the reactor chamber. Reducing gas is added at different stages in the process to form a desired end product and prevent back reactions. The resulting heated gaseous stream is then rapidly cooled by expansion of the gaseous stream. 8 figs.

  4. Fast quench reactor method

    DOEpatents

    Detering, Brent A.; Donaldson, Alan D.; Fincke, James R.; Kong, Peter C.; Berry, Ray A.

    1999-01-01

    A fast quench reaction includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a means of rapidly expanding a reactant stream, such as a restrictive convergent-divergent nozzle at its outlet end. Metal halide reactants are injected into the reactor chamber. Reducing gas is added at different stages in the process to form a desired end product and prevent back reactions. The resulting heated gaseous stream is then rapidly cooled by expansion of the gaseous stream.

  5. Factors of Stream Instability in Urban Centres of Southern Nigeria: Case Study of Port Harcourt City River Systems.

    NASA Astrophysics Data System (ADS)

    Amangabara, G. T.

    2006-05-01

    There are two main drainage rivers in the Port Harcourt Metropolis - The Ntamogba and the Woji creek (Abam, 2004). There are a few other drainage rivers that are equally important e.g. the Nwaja River that drains Rumukalagbor, Elekahia, New GRA Phases IV and V, Presidential Housing Estate and Sun Ray publications Area of Aba Road. These river systems drain the entire Port Harcourt City dividing the City into three major drainage zones. Since the discovery of oil in Nigeria in the 1950s, the country has been suffering the negative environmental consequences of oil development. The growth of the country's oil industry, combined with population explosion and a lack of environmental regulations, led to substantial damage to Nigeria's environment, especially in the Niger Delta region, the center of the country's oil industry. Uncontrolled population movement as well as spontaneous housing development on marginal lands such as stream corridors, has led to the degradation of all major stream channels in the Nation's oil capital - Port Harcourt City. The longitudinal profiles and cross sections of reaches of three major streams (Ntamogba, Nwaja, and Oginigba streams) were investigated. Land use maps of 1979 1999 and 2004 were used. Our result showed that 1). Almost all of the stream corridors have been built up without adequate plan 2). The natural grades have been distorted by channelisation for the purpose of flood evacuation without geomorphic consideration .3). Our research also shows that the interface of saline water and fresh water has extended upstream affecting urban infrastructure. 4) localized damming and sedimentation behind hydraulic structures were common occurrences) our overall result indicate that two episodes of channel incision on Oginigba stream had increased slope reduced sinuosity increased entrenchment and reduce width-depth ratio . Conclusively the factors of the instability of theses urban streams are manly the processes of urbanization which include waste dumping channelisation and unregulated housing development in the channel corridors. KEY WORDS: stream instability, marginal lands, stream corridor, saline environment, spontaneous, geomorphic, channelisation

  6. Shocklike soliton because of an impinge of protons and electrons solar particles with Venus ionosphere

    NASA Astrophysics Data System (ADS)

    Moslem, W. M.; Rezk, S.; Abdelsalam, U. M.; El-Labany, S. K.

    2018-04-01

    This paper introduces an investigation of shocklike soliton or small amplitude Double Layers (DLs) in a collisionless plasma, consisting of positive and negative ions, nonthermal electrons, as well as solar wind streaming protons and electrons. Gardner equation is derived and its shocklike soliton solution is obtained. The model is employed to recognize a possible nonlinear wave at Venus ionosphere. The results indicate that the number densities and velocities of the streaming particles play crucial role to determine the polarity and characteristic features (amplitude and width) of the shocklike soliton waves. An electron streaming speed modifies a negative shocklike wave profile, while an ion streaming speed modulates a positive shocklike wave characteristic.

  7. Void/particulate detector

    DOEpatents

    Claytor, Thomas N.; Karplus, Henry B.

    1985-01-01

    Voids and particulates are detected in a flowing stream of fluid contained in a pipe by a detector which includes three transducers spaced about the pipe. A first transducer at a first location on the pipe transmits an ultrasonic signal into the stream. A second transducer detects the through-transmission of the signal at a second location and a third transducer at a third location upstream from the first location detects the back-scattering of the signal from any voids or particulates. To differentiate between voids and particulates a fourth transducer is positioned at a fourth location which is also upstream from the first location. The back-scattered signals are normalized with the through-transmission signal to minimize temperature fluctuations.

  8. Void/particulate detector

    DOEpatents

    Claytor, T.N.; Karplus, H.B.

    1983-09-26

    Apparatus for detecting voids and particulates in a flowing stream of fluid contained in a pipe may comprise: (a) a transducer for transmitting an ultrasonic signal into the stream, coupled to the pipe at a first location; (b) a second transducer for detecting the through-transmission of said signal, coupled to the pipe at a second location; (c) a third transducer for detecting the back-scattering of said signal, coupled to the pipe at a third location, said third location being upstream from said first location; (d) circuit means for normalizing the back-scattered signal from said third transducer to the through-transmitted signal from said second transducer; which normalized signal provides a measure of the voids and particulates flowing past said first location.

  9. Fluid aspects of electron streaming instability in electron-ion plasmas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jao, C.-S.; Hau, L.-N.; Department of Physics, National Central University, Jhongli, Taiwan

    2014-02-15

    Electrons streaming in a background electron and ion plasma may lead to the formation of electrostatic solitary wave (ESW) and hole structure which have been observed in various space plasma environments. Past studies on the formation of ESW are mostly based on the particle simulations due to the necessity of incorporating particle's trapping effects. In this study, the fluid aspects and thermodynamics of streaming instabilities in electron-ion plasmas including bi-streaming and bump-on-tail instabilities are addressed based on the comparison between fluid theory and the results from particle-in-cell simulations. The energy closure adopted in the fluid model is the polytropic lawmore » of d(pρ{sup −γ})/dt=0 with γ being a free parameter. Two unstable modes are identified for the bump-on-tail instability and the growth rates as well as the dispersion relation of the streaming instabilities derived from the linear theory are found to be in good agreement with the particle simulations for both bi-streaming and bump-on-tail instabilities. At the nonlinear saturation, 70% of the electrons are trapped inside the potential well for the drift velocity being 20 times of the thermal velocity and the pρ{sup −γ} value is significantly increased. Effects of ion to electron mass ratio on the linear fluid theory and nonlinear simulations are also examined.« less

  10. Process for recovering organic components from liquid streams

    DOEpatents

    Blume, Ingo; Baker, Richard W.

    1991-01-01

    A separation process for recovering organic components from liquid streams. The process is a combination of pervaporation and decantation. In cases where the liquid stream contains the organic to be separated in dissolved form, the pervaporation step is used to concentrate the organic to a point above the solubility limit, so that a two-phase permeate is formed and then decanted. In cases where the liquid stream is a two-phase mixture, the decantation step is performed first, to remove the organic product phase, and the residue from the decanter is then treated by pervaporation. The condensed permeate from the pervaporation unit is sufficiently concentrated in the organic component to be fed back to the decanter. The process can be tailored to produce only two streams: an essentially pure organic product stream suitable for reuse, and a residue stream for discharge or reuse.

  11. Performance of the full size nGEM detector for the SPIDER experiment

    NASA Astrophysics Data System (ADS)

    Muraro, A.; Croci, G.; Albani, G.; Claps, G.; Cavenago, M.; Cazzaniga, C.; Dalla Palma, M.; Grosso, G.; Murtas, F.; Pasqualotto, R.; Perelli Cippo, E.; Rebai, M.; Tardocchi, M.; Tollin, M.; Gorini, G.

    2016-03-01

    The ITER neutral beam test facility under construction in Padova will host two experimental devices: SPIDER, a 100 kV negative H/D RF beam source, and MITICA, a full scale, 1 MeV deuterium beam injector. SPIDER will start operations in 2016 while MITICA is expected to start during 2019. Both devices feature a beam dump used to stop the produced deuteron beam. Detection of fusion neutrons produced between beam-deuterons and dump-implanted deuterons will be used as a means to resolve the horizontal beam intensity profile. The neutron detection system will be placed right behind the beam dump, as close to the neutron emitting surface as possible thus providing the map of the neutron emission on the beam dump surface. The system uses nGEM neutron detectors. These are Gas Electron Multiplier detectors equipped with a cathode that also serves as neutron-proton converter foil. The cathode is designed to ensure that most of the detected neutrons at a point of the nGEM surface are emitted from the corresponding beamlet footprint (with dimensions of about 40×22 mm2) on the dump front surface. The size of the nGEM detector for SPIDER is 352 mm×200 mm. Several smaller size prototypes have been successfully made in the last years and the experience gained on these detectors has led to the production of the full size detector for SPIDER during 2014. This nGEM has a read-out board made of 256 pads (arranged in a 16×16 matrix) each with a dimension of 22 mm×13 mm. This paper describes the production of this detector and its tests (in terms of beam profile reconstruction capability, uniformity over the active area, gamma rejection capability and time stability) performed on the ROTAX beam-line at the ISIS spallation source (Didcot-UK).

  12. Coal Mining and Post-Metallurgic Dumping Grounds and Their Connections with Exploitation of Raw Materials in the Region of Ruda Śląska

    NASA Astrophysics Data System (ADS)

    Jonczy, Iwona; Gawor, Łukasz

    2017-06-01

    Characteristics of mining and metallurgical waste dumps in Ruda Śląska was presented in this article. Special attention was paid to the relationship of waste material accumulated on the dumps with resources exploited on studied area. The possibilities of dumps management were also traced and two directions were indicated. The first one is associated with forming a biological covering on the dumps and the second one - with the dumps liquidation and with recovery areas now occupied by the dumps and thus with the secondary use of material collected on them.

  13. Strong field control of predissociation dynamics.

    PubMed

    Corrales, María E; Balerdi, Garikoitz; Loriot, Vincent; de Nalda, Rebeca; Bañares, Luis

    2013-01-01

    Strong field control scenarios are investigated in the CH3I predissociation dynamics at the origin of the second absorption B-band, in which state-selective electronic predissociation occurs through the crossing with a valence dissociative state. Dynamic Stark control (DSC) and pump-dump strategies are shown capable of altering both the predissociation lifetime and the product branching ratio.

  14. 77 FR 61819 - WTO Dispute Settlement Proceeding Regarding United States-Countervailing and Anti-Dumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-11

    ... comments should be submitted electronically to www.regulations.gov , docket number USTR-2012-0031. If you...); Light-Walled Rectangular Pipe and Tube (C-570-915); Laminated Woven Sacks (C-570-917); Certain New... Rectangular Pipe and Tube (A-570-916); Laminated Woven Sacks (A-570-914); Certain New Pneumatic Off-The-Road...

  15. Acceleration of plasma electrons by intense nonrelativistic ion and electron beams propagating in background plasma due to two-stream instability

    NASA Astrophysics Data System (ADS)

    Kaganovich, Igor D.

    2015-11-01

    In this paper we study the effects of the two-stream instability on the propagation of intense nonrelativistic ion and electron beams in background plasma. Development of the two-stream instability between the beam ions and plasma electrons leads to beam breakup, a slowing down of the beam particles, acceleration of the plasma particles, and transfer of the beam energy to the plasma particles and wave excitations. Making use of the particle-in-cell codes EDIPIC and LSP, and analytic theory we have simulated the effects of the two-stream instability on beam propagation over a wide range of beam and plasma parameters. Because of the two-stream instability the plasma electrons can be accelerated to velocities as high as twice the beam velocity. The resulting return current of the accelerated electrons may completely change the structure of the beam self - magnetic field, thereby changing its effect on the beam from focusing to defocusing. Therefore, previous theories of beam self-electromagnetic fields that did not take into account the effects of the two-stream instability must be significantly modified. This effect can be observed on the National Drift Compression Experiment-II (NDCX-II) facility by measuring the spot size of the extracted beamlet propagating through several meters of plasma. Particle-in-cell, fluid simulations, and analytical theory also reveal the rich complexity of beam- plasma interaction phenomena: intermittency and multiple regimes of the two-stream instability in dc discharges; band structure of the growth rate of the two-stream instability of an electron beam propagating in a bounded plasma and repeated acceleration of electrons in a finite system. In collaboration with E. Tokluoglu, D. Sydorenko, E. A. Startsev, J. Carlsson, and R. C. Davidson. Research supported by the U.S. Department of Energy.

  16. Speciation and fate of copper in sewage treatment works with and without tertiary treatment: the effect of return flows.

    PubMed

    Innaa, D; Lester, J N; Scrimshawb, M D; Cartmell, E

    2014-01-01

    The removal of metals from wastewaters is becoming an important issue, with new environmental quality standards putting increased regulatory pressure on operators of sewage treatment works. The use of additional processes (tertiary treatment) following two-stage biological treatment is frequently seen as a way of improving effluent quality for nutrients and suspended solids, and this study investigates the impact of how back washes from these tertiary processes may impact the removal of copper during primary sedimentation. Seven sites were studied, three conventional two-stage biological treatment, and four with tertiary processes. It was apparent that fluxes of copper in traditional return flows made a significant contribution to the load to the primary treatment tanks, and that <1% of this was in the dissolved phase. Where tertiary processes were used, back wash liquors were also returned to the primary tanks. These return flows had an impact on copper removal in the primary tanks, probably due to their aerobic nature. Returning such aerobic back wash flows to the main process stream after primary treatment may therefore be worth consideration. The opportunity to treat consolidated liquor and sludge.flows in side-stream processes to remove toxic elements, as they are relatively concentrated, low volume flow streams, should also be evaluated.

  17. Measurements of the energy spectrum of electrons emanating from solid materials irradiated by a picosecond laser

    DOE PAGES

    Di Stefano, C. A.; Kuranz, C. C.; Seely, J. F.; ...

    2015-04-01

    Here, we present the results of experiments observing the properties of the electron stream generated laterally when a laser irradiates a metal. We also found that the directionality of the electrons is dependent upon their energies, with the higher-energy tail of the spectrum ( 1MeV and higher) being more narrowly focused. This behavior is likely due to the coupling of the electrons to the electric field of the laser. We performed these experiments by using the Titan laser to irradiate a metal wire, creating the electron stream of interest. These electrons propagate to nearby spectator wires of differing metals, causingmore » them to fluoresce at their characteristic K-shell energies. This fluorescence is recorded by a crystal spectrometer. By varying the distances between the wires, we are able to probe the divergence of the electron stream, while by varying the medium through which the electrons propagate (and hence the energy-dependence of electron attenuation), we are able to probe the energy spectrum of the stream.« less

  18. Electrostatic streaming instability modes in complex viscoelastic quantum plasmas

    NASA Astrophysics Data System (ADS)

    Karmakar, P. K.; Goutam, H. P.

    2016-11-01

    A generalized quantum hydrodynamic model is procedurally developed to investigate the electrostatic streaming instability modes in viscoelastic quantum electron-ion-dust plasma. Compositionally, inertialess electrons are anticipated to be degenerate quantum particles owing to their large de Broglie wavelengths. In contrast, inertial ions and dust particulates are treated in the same classical framework of linear viscoelastic fluids (non-Newtonian). It considers a dimensionality-dependent Bohmian quantum correction prefactor, γ = [(D - 2)/3D], in electron quantum dynamics, with D symbolizing the problem dimensionality. Applying a regular Fourier-formulaic plane-wave analysis around the quasi-neutral hydrodynamic equilibrium, two distinct instabilities are explored to exist. They stem in ion-streaming (relative to electrons and dust) and dust-streaming (relative to electrons and ions). Their stability is numerically illustrated in judicious parametric windows in both the hydrodynamic and kinetic regimes. The non-trivial influential roles by the relative streams, viscoelasticities, and correction prefactor are analyzed. It is seen that γ acts as a stabilizer for the ion-stream case only. The findings alongside new entailments, as special cases of realistic interest, corroborate well with the earlier predictions in plasma situations. Applicability of the analysis relevant in cosmic and astronomical environments of compact dwarf stars is concisely indicated.

  19. Managing Ocean Dumping in EPA Region 4

    EPA Pesticide Factsheets

    Overview of ocean dumping in Southeast United States. Includes materials dumped in the Region, ocean dumping permits issues, dredged material testing guidance, ocean disposal site descriptions and information, regional dredging teams and other partnerships

  20. Managing Ocean Dumping in EPA Region 1

    EPA Pesticide Factsheets

    Overview of ocean dumping in New England, US. Includes materials dumped in the Region, ocean dumping permits issues, dredged material testing guidance, ocean disposal site descriptions and information, regional dredging teams and other partnerships.

  1. Managing Ocean Dumping in EPA Region 6

    EPA Pesticide Factsheets

    Overview of ocean dumping in South Central, US. Includes materials dumped in the Region, ocean dumping permits issues, dredged material testing guidance, ocean disposal site descriptions and information, regional dredging teams and other partnerships

  2. Managing Ocean Dumping in EPA Region 3

    EPA Pesticide Factsheets

    Overview of ocean dumping in Mid Atlantic, US. Includes materials dumped in the Region, ocean dumping permits issues, dredged material testing guidance, ocean disposal site descriptions and information, regional dredging teams and other partnerships.

  3. Managing Ocean Dumping in EPA Region 9

    EPA Pesticide Factsheets

    Overview of ocean dumping in EPA Pacific Southwest. Includes materials dumped in the Region, ocean dumping permits issues, dredged material testing guidance, ocean disposal site descriptions and information, regional dredging teams and other partnerships.

  4. Managing Ocean Dumping in EPA Region 10

    EPA Pesticide Factsheets

    Overview of ocean dumping in Pacific Northwest, US. Includes materials dumped in the Region, ocean dumping permits issues, dredged material testing guidance, ocean disposal site descriptions and information, regional dredging teams and other partnerships.

  5. Anomalous auroral electron distributions due to an artificial ion beam in the ionosphere

    NASA Technical Reports Server (NTRS)

    Moore, T. E.; Arnoldy, R. L.; Kaufmann, R. L.; Cahill, L. J., Jr.; Kintner, P. M.; Walker, D. N.

    1982-01-01

    Results are reported for the perturbation of the auroral ionosphere by the operation of an ion gun which injected about 100 mA of 25-eV Ar(+) ions at upgoing pitch angles over a discrete auroral arc. The major effects observed were the excitation of intense broadband electric field fluctuations at zero-10 kHz, and the appearance of streaming and isotropic heating in different parts of superthermal electron velocity space. A scenario is explored in which electron runaway or streaming is expected between the trapping speed and the critical velocity for cyclotron interactions with the waves, where the streaming electrons carry the current that would be carried by thermals or energetic electrons in the absence of the waves. A current of about 1.0 microA/sq m is carried by the streaming electrons. The gun-associated electrons were anomalous in the sense that their anisotropy was the opposite of that observed in the natural aurora.

  6. Evaluation of composting as a strategy for managing organic wastes from a municipal market in Nicaragua.

    PubMed

    Aulinas Masó, Montserrat; Bonmatí Blasi, August

    2008-07-01

    A pilot-scale study was undertaken to evaluate alternatives to the solid waste management of a Central American municipal market located in Estelí, Nicaragua. The municipal solid waste from the local market is the second largest contributor to the municipal solid waste (MSW) stream. Waste from the market without any previous sorting or treatment is open dumped. The options evaluated in this study were windrow composting, windrow composting with yard waste, bokashi and vermicompost. Significant differences between the properties of composts produced were found; however, all of them reduce the initial waste volume and are potential useful agronomic products for a survival agrarian milieu.

  7. Automatic electronic fish tracking system

    NASA Technical Reports Server (NTRS)

    Osborne, P. W.; Hoffman, E.; Merriner, J. V.; Richards, C. E.; Lovelady, R. W.

    1976-01-01

    A newly developed electronic fish tracking system to automatically monitor the movements and migratory habits of fish is reported. The system is aimed particularly at studies of effects on fish life of industrial facilities which use rivers or lakes to dump their effluents. Location of fish is acquired by means of acoustic links from the fish to underwater Listening Stations, and by radio links which relay tracking information to a shore-based Data Base. Fish over 4 inches long may be tracked over a 5 x 5 mile area. The electronic fish tracking system provides the marine scientist with electronics which permit studies that were not practical in the past and which are cost-effective compared to manual methods.

  8. Spoil pile instabilities with reference to a strip coal mine in Turkey: mechanisms and assessment of deformations

    NASA Astrophysics Data System (ADS)

    Kasmer, Ozgu; Ulusay, Resat; Gokceoglu, Candan

    2006-02-01

    With the increasing adoption of the surface mining of coal, problems associated with spoil pile instability, which affects resource recovery, mining cost, and safety and presents environmental hazards, have become a matter of prime concern to mine planners and operators. The study of geotechnical aspects is thus very important in the rational planning for the disposal, reclamation, treatment and utilization of spoil material. A strip coal mine, one of the largest open pit mines in Turkey, is located in Central Anatolia and provides coal to a thermal power station. Coal production is carried out in two adjacent open pits, the Central Pit and South Pit. A large-scale spoil pile instability over an area of 0.3 km2 occurred within the dumping area of the Central pit. In addition, small-scale movement occurred in the outside dumping area. This paper outlines the results of field and laboratory investigations to describe the mechanisms of the spoil pile instabilities and to assess deformations monitored over a long period following the failure. Shear test results indicate that the interface between the floor and spoil material dumped by dragline has a negligible cohesion and is the most critical plane of weakness for spoil pile instability. Back analyses based on the method of limit equilibrium and the numerical modelling technique, and observations in the pit revealed that failure occurred along a combined sliding surface consisting of a circular surface through the spoil material itself and a planar surface passing along the interface between the spoil piles and floor. The analyses also indicated that pore water pressure ratios of about 0.25 satisfy limiting equilibrium condition and that rainfall about one month before the failure may be a contributing factor to the instability. Movement monitoring data obtained following the failure over a 1.5-year period suggested that the ongoing deformations were mainly due to compaction of the spoil material. Based on the monitoring data and the results of the analyses, the failure mode of the local instability occurring at the outside dumping area was considerably similar to that of the large instability.

  9. 40 CFR 228.15 - Dumping sites designated on a final basis.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Dumping sites designated on a final basis. 228.15 Section 228.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.15 Dumping sites designated on a final basis. (a)(1) The sites...

  10. 40 CFR 228.15 - Dumping sites designated on a final basis.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Dumping sites designated on a final basis. 228.15 Section 228.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.15 Dumping sites designated on a final basis. (a)(1) The sites...

  11. 40 CFR 228.15 - Dumping sites designated on a final basis.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Dumping sites designated on a final basis. 228.15 Section 228.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.15 Dumping sites designated on a final basis. (a)(1) The sites...

  12. 40 CFR 228.15 - Dumping sites designated on a final basis.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Dumping sites designated on a final basis. 228.15 Section 228.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.15 Dumping sites designated on a final basis. (a)(1) The sites...

  13. Tracking Stripped Proton Particles in SNS Ring Injection Momentum Dump Line

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Jian-Guang

    3D computer simulations are performed to study magnetic field distributions and particle trajectories along the SNS ring injection momentum dump line. Optical properties and transfer maps along the dump line are calculated. The stripped proton particle distributions on the dump window are analyzed. The study has provided useful information for the redesign of the SNS ring injection beam dump.

  14. Managing Ocean Dumping in EPA Region 2

    EPA Pesticide Factsheets

    Overview of ocean dumping in NY, NJ and Puerto Rico. Includes materials dumped in the Region, ocean dumping permits issues, dredged material testing guidance, ocean disposal site descriptions and information, regional dredging teams and other partnerships

  15. Geology beneath and beside the notorious Payatas open dump, Metro Manila, Philippines

    NASA Astrophysics Data System (ADS)

    Tomarong, C.; Arcilla, C.; de Sales, L.; Chua, S.; Garcia, E.; Pamintuan, G.

    2003-04-01

    With a minimum of 6000 tonnes/day municipal waste output, and with NO existing operational sanitary landfill and with incineration illegal, Metro Manila has a very serious solid waste disposal problem. Unsorted municipal waste are being piled in open dumps, the most notorious of which is the Payatas open dump. A recent, tragic garbage-slide in this open dump caused dozens of deaths, news of which were broadcast internationally. Political expediency laced with a lot of corruption, rather than sound science, was the main basis for selecting this site as an open dump. As an example, this dump is situated < 1 km from the Novaliches Watershed Reservation, one of the main sources of drinking water for Metro Manila’s 12 million population! Yet, after dumping operations that have lasted more than 10 years, only recently were the preliminary geologic studies begun. Payatas is not a designed landfill and its untreated leachate is openly polluting the headwaters of the Marikina and Pasig Rivers. In addition, during the summer months, there is always the constant threat of fire due to methane induced burning from the dump, aside from the aerial pollution from dioxins and furans derived from incomplete combustion of municipal solid waste. With limited funding from the Quezon City government, a feasibility study was conducted to assess the methane generation potential of Payatas. This interdisciplinary study comprised bedrock geological studies, topographic mapping of the dump, drilling of the dump to obtain stratigraphic solid waste samples for waste characterization, laying of horizontal methane and dewatering pipes, and preliminary methane flow studies. The waste characterization has highlighted the unusually high organic (especially yard waste) component of the solid waste dumped at Payatas. Waste characterization shows that a significant portion of the waste is plastics. Several cross-sections cut across the dump show that the side slopes of the dump are on the average steeper than the pre-dump slopes. The “bedrock” of the Payatas dump are conglomerate members of the Pleistocene volcaniclastic Guadualupe Formation. Studies are still to be done on the extent of pollution on surface and groundwater in the Payatas environs.

  16. Major Pathways to Electron Distribution Function Formation in Regions of Diffuse Aurora

    NASA Technical Reports Server (NTRS)

    Khazanov, George V.; Sibeck, David G.; Zesta, Eftyhia

    2017-01-01

    This paper discusses the major pathways of electron distribution function formation in the region of diffuse aurora. The diffuse aurora accounts for about of 75% of the auroral energy precipitating into the upper atmosphere, and its origin has been the subject of much discussion. We show that an earthward stream of precipitating electrons initially injected from the Earth's plasma sheet via wave-particle interactions degrades in the atmosphere toward lower energies and produces secondary electrons via impact ionization of the neutral atmosphere. These electrons of magnetospheric origin are then reflected back into the magnetosphere along closed dipolar magnetic field lines, leading to a series of reflections and consequent magnetospheric interactions that greatly augment the initially precipitating flux at the upper ionospheric boundary (700-800 km). To date this, systematic magnetosphere-ionosphere coupling element has not been included in auroral research models, and, as we demonstrate in this article, has a dramatic effect (200-300%) on the formation of the precipitating fluxes that result in the diffuse aurora. It is shown that wave-particle interaction processes that drive precipitating fluxes in the region of diffuse aurora from the magnetospheric altitudes are only the first step in the formation of electron precipitation at ionospheric altitudes, and they cannot be separated from the atmospheric collisional machine that redistributes and transfers their energy inside the magnetosphere-ionosphere-atmosphere coupling system.

  17. Major pathways to electron distribution function formation in regions of diffuse aurora

    NASA Astrophysics Data System (ADS)

    Khazanov, George V.; Sibeck, David G.; Zesta, Eftyhia

    2017-04-01

    This paper discusses the major pathways of electron distribution function formation in the region of diffuse aurora. The diffuse aurora accounts for about of 75% of the auroral energy precipitating into the upper atmosphere, and its origin has been the subject of much discussion. We show that an earthward stream of precipitating electrons initially injected from the Earth's plasma sheet via wave-particle interactions degrades in the atmosphere toward lower energies and produces secondary electrons via impact ionization of the neutral atmosphere. These electrons of magnetospheric origin are then reflected back into the magnetosphere along closed dipolar magnetic field lines, leading to a series of reflections and consequent magnetospheric interactions that greatly augment the initially precipitating flux at the upper ionospheric boundary (700-800 km). To date this, systematic magnetosphere-ionosphere coupling element has not been included in auroral research models, and, as we demonstrate in this article, has a dramatic effect (200-300%) on the formation of the precipitating fluxes that result in the diffuse aurora. It is shown that wave-particle interaction processes that drive precipitating fluxes in the region of diffuse aurora from the magnetospheric altitudes are only the first step in the formation of electron precipitation at ionospheric altitudes, and they cannot be separated from the atmospheric "collisional machine" that redistributes and transfers their energy inside the magnetosphere-ionosphere-atmosphere coupling system.

  18. Specific Features of Dumping Syndrome after Various Types of Gastrectomy as Assessed by a Newly Developed Integrated Questionnaire, the PGSAS-45.

    PubMed

    Tanizawa, Yutaka; Tanabe, Kazuaki; Kawahira, Hiroshi; Fujita, Junya; Takiguchi, Nobuhiro; Takahashi, Masazumi; Ito, Yuichi; Mitsumori, Norio; Namikawa, Tsutomu; Oshio, Atsushi; Nakada, Koji

    2016-01-01

    Dumping syndrome is a well-known adverse outcome after gastrectomy, but the precise clinical features have not been described. The aim of this study was to examine global aspects of dumping syndrome and to explore factors affecting the intensity of dumping syndrome in a large cohort using a newly developed integrated questionnaire, the Post-Gastrectomy Syndrome Assessment Scale (PGSAS)-45. Eligible questionnaires retrieved from 2,368 patients after 6 types of gastrectomy were analyzed. The incidence, intensity and number of symptoms of early general, early abdominal and late dumping syndrome were examined across various types of gastrectomy, and clinical factors affecting the intensity of each category of dumping syndrome were identified by multiple regression analysis. Dumping syndromes occurred most frequently and strongly in patients who underwent total gastrectomy with Roux-en-Y (TGRY), followed by proximal gastrectomy (PG), distal gastrectomy with Billroth-I, distal gastrectomy with Roux-en-Y, pylorus-preserving gastrectomy (PPG) and local resection (LR), in that order. Significant positive correlations among different categories of dumping syndromes were observed. TGRY, female sex, younger age, division of the celiac branch of the vagus nerve, PG and shorter postoperative period were independently related to worse dumping syndrome. Dumping syndromes were most common after TGRY and least common after PPG and LR among the various gastrectomy procedures. Type of gastrectomy and several clinical factors were related to the intensity of dumping syndrome. PGSAS-45 could offer a useful tool for evaluating dumping syndrome after gastrectomy. © 2015 S. Karger AG, Basel.

  19. Photo-stimulated low electron temperature high current diamond film field emission cathode

    DOEpatents

    Shurter,; Roger Philips, Devlin [Los Alamos, NM; David James, Moody [Santa Fe, NM; Nathan Andrew, Taccetti [Los Alamos, NM; Jose Martin, Russell [Santa Fe, NM; John, Steven [Los Alamos, NM

    2012-07-24

    An electron source includes a back contact surface having a means for attaching a power source to the back contact surface. The electron source also includes a layer comprising platinum in direct contact with the back contact surface, a composite layer of single-walled carbon nanotubes embedded in platinum in direct contact with the layer comprising platinum. The electron source also includes a nanocrystalline diamond layer in direct contact with the composite layer. The nanocrystalline diamond layer is doped with boron. A portion of the back contact surface is removed to reveal the underlying platinum. The electron source is contained in an evacuable container.

  20. Gas separation process using membranes with permeate sweep to remove CO.sub.2 from gaseous fuel combustion exhaust

    DOEpatents

    Wijmans, Johannes G [Menlo Park, CA; Merkel, Timothy C [Menlo Park, CA; Baker, Richard W [Palo Alto, CA

    2012-05-15

    A gas separation process for treating exhaust gases from the combustion of gaseous fuels, and gaseous fuel combustion processes including such gas separation. The invention involves routing a first portion of the exhaust stream to a carbon dioxide capture step, while simultaneously flowing a second portion of the exhaust gas stream across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas back to the combustor.

  1. Electronic waste - an emerging threat to the environment of urban India.

    PubMed

    Needhidasan, Santhanam; Samuel, Melvin; Chidambaram, Ramalingam

    2014-01-20

    Electronic waste or e-waste is one of the emerging problems in developed and developing countries worldwide. It comprises of a multitude of components with valuable materials, some containing toxic substances, that can have an adverse impact on human health and the environment. Previous studies show that India has generated 0.4 million tons of e-waste in 2010 which may increase to 0.5 to 0.6 million tons by 2013-2014. Coupled with lack of appropriate infrastructural facilities and procedures for its disposal and recycling have posed significant importance for e-waste management in India. In general, e-waste is generated through recycling of e-waste and also from dumping of these wastes from other countries. More of these wastes are ending up in dumping yards and recycling centers, posing a new challenge to the environment and policy makers as well. In general electronic gadgets are meant to make our lives happier and simpler, but the toxicity it contains, their disposal and recycling becomes a health nightmare. Most of the users are unaware of the potential negative impact of rapidly increasing use of computers, monitors, and televisions. This review article provides a concise overview of India's current e-waste scenario, namely magnitude of the problem, environmental and health hazards, current disposal, recycling operations and mechanisms to improve the condition for better environment.

  2. Electronic waste – an emerging threat to the environment of urban India

    PubMed Central

    2014-01-01

    Electronic waste or e-waste is one of the emerging problems in developed and developing countries worldwide. It comprises of a multitude of components with valuable materials, some containing toxic substances, that can have an adverse impact on human health and the environment. Previous studies show that India has generated 0.4 million tons of e-waste in 2010 which may increase to 0.5 to 0.6 million tons by 2013–2014. Coupled with lack of appropriate infrastructural facilities and procedures for its disposal and recycling have posed significant importance for e-waste management in India. In general, e-waste is generated through recycling of e-waste and also from dumping of these wastes from other countries. More of these wastes are ending up in dumping yards and recycling centers, posing a new challenge to the environment and policy makers as well. In general electronic gadgets are meant to make our lives happier and simpler, but the toxicity it contains, their disposal and recycling becomes a health nightmare. Most of the users are unaware of the potential negative impact of rapidly increasing use of computers, monitors, and televisions. This review article provides a concise overview of India’s current e-waste scenario, namely magnitude of the problem, environmental and health hazards, current disposal, recycling operations and mechanisms to improve the condition for better environment. PMID:24444377

  3. Geometrical Optimization Approach to Isomerization: Models and Limitations.

    PubMed

    Chang, Bo Y; Shin, Seokmin; Engel, Volker; Sola, Ignacio R

    2017-11-02

    We study laser-driven isomerization reactions through an excited electronic state using the recently developed Geometrical Optimization procedure. Our goal is to analyze whether an initial wave packet in the ground state, with optimized amplitudes and phases, can be used to enhance the yield of the reaction at faster rates, driven by a single picosecond pulse or a pair of femtosecond pulses resonant with the electronic transition. We show that the symmetry of the system imposes limitations in the optimization procedure, such that the method rediscovers the pump-dump mechanism.

  4. Unfair trade: e-waste in Africa.

    PubMed

    Schmidt, Charles W

    2006-04-01

    Africa is quickly becoming a destination for information technology in the form of tons of used computers, fax machines, cell phones, and other electronics. Although many of these machines can be repaired and resold, up to 75% of the electronics shipped to Africa is junk. This equipment, when dumped, may leach lead, mercury, and cadmium into the environment; when burned, it may release carcinogenic dioxins and polyaromatic hydrocarbons. In the United States, activists are working to limit the flow of e-waste to developing countries through international agreements and voluntary e-waste export reduction efforts.

  5. Design of a Compact Coaxial Magnetized Plasma Gun for Magnetic Bubble Expansion Experiments

    DTIC Science & Technology

    2009-06-01

    a peak a current Igun~ 80 kA and gun voltages Vgun~1 kV utine operation at a bank voltage of 7.5 kV yiel plasm after breakdown. Typical Igun and...and D2 are power electronic diodes, SW is the dump relay and C is the bias flux capacitor bank. The SCR, controlled by a 1 kV Trigger Pulse...capacitor charging circuit is shown in Figure 8. Figure 8. Gas valve capacitor charging circuit diagram 0 kΩ. 1, D2 and D3 are power electronic

  6. Anaerobic Metabolism and Bioremediation of Explosives-Contaminated Soil

    NASA Astrophysics Data System (ADS)

    Boopathy, Raj

    Nitroaromatic compounds pollute soil, water, and food via use of pesticides, plastics, pharmaceuticals, landfill dumping of industrial wastes, and the military use of explosives. Biotransformation of trinitrotoluene and other nitroaromatics by aerobic bacteria in the laboratory has been frequently reported, but the anaerobic bacterial metabolism of nitroaromatics has not been studied as extensively perhaps due to the difficulty in working with anaerobic cultures and the slow growth of anaerobes. Sulfate-reducing and methanogenic bacteria can metabolize nitroaromatic compounds under anaerobic conditions if appropriate electron donors and electron acceptors are present in the environment.

  7. Back-end and interface implementation of the STS-XYTER2 prototype ASIC for the CBM experiment

    NASA Astrophysics Data System (ADS)

    Kasinski, K.; Szczygiel, R.; Zabolotny, W.

    2016-11-01

    Each front-end readout ASIC for the High-Energy Physics experiments requires robust and effective hit data streaming and control mechanism. A new STS-XYTER2 full-size prototype chip for the Silicon Tracking System and Muon Chamber detectors in the Compressed Baryonic Matter experiment at Facility for Antiproton and Ion Research (FAIR, Germany) is a 128-channel time and amplitude measuring solution for silicon microstrip and gas detectors. It operates at 250 kHit/s/channel hit rate, each hit producing 27 bits of information (5-bit amplitude, 14-bit timestamp, position and diagnostics data). The chip back-end implements fast front-end channel read-out, timestamp-wise hit sorting, and data streaming via a scalable interface implementing the dedicated protocol (STS-HCTSP) for chip control and hit transfer with data bandwidth from 9.7 MHit/s up to 47 MHit/s. It also includes multiple options for link diagnostics, failure detection, and throttling features. The back-end is designed to operate with the data acquisition architecture based on the CERN GBTx transceivers. This paper presents the details of the back-end and interface design and its implementation in the UMC 180 nm CMOS process.

  8. Photoisomerization and photoionization of the photoactive yellow protein chromophore in solution.

    PubMed

    Larsen, Delmar S; Vengris, Mikas; van Stokkum, Ivo H M; van der Horst, Michael A; de Weerd, Frank L; Hellingwerf, Klaas J; van Grondelle, Rienk

    2004-04-01

    Dispersed pump-dump-probe spectroscopy has the ability to characterize and identify the underlying ultrafast dynamical processes in complicated chemical and biological systems. This technique builds on traditional pump-probe techniques by exploring both ground- and excited-state dynamics and characterizing the connectivity between constituent transient states. We have used the dispersed pump-dump-probe technique to investigate the ground-state dynamics and competing excited-state processes in the excitation-induced ultrafast dynamics of thiomethyl p-coumaric acid, a model chromophore for the photoreceptor photoactive yellow protein. Our results demonstrate the parallel formation of two relaxation pathways (with multiple transient states) that jointly lead to two different types of photochemistry: cis-trans isomerization and detachment of a hydrated electron. The relative transition rates and quantum yields of both pathways have been determined. We find that the relaxation of the photoexcited chromophores involves multiple, transient ground-state intermediates and the chromophore in solution does not generate persistent photoisomerized products, but instead undergoes photoionization resulting in the generation of detached electrons and radicals. These results are of great value in interpreting the more complex dynamical changes in the optical properties of the photoactive yellow protein.

  9. Optimal initiation of electronic excited state mediated intramolecular H-transfer in malonaldehyde by UV-laser pulses

    NASA Astrophysics Data System (ADS)

    Nandipati, K. R.; Singh, H.; Nagaprasad Reddy, S.; Kumar, K. A.; Mahapatra, S.

    2014-12-01

    Optimally controlled initiation of intramolecular H-transfer in malonaldehyde is accomplished by designing a sequence of ultrashort (~80 fs) down-chirped pump-dump ultra violet (UV)-laser pulses through an optically bright electronic excited [ S 2 ( π π ∗)] state as a mediator. The sequence of such laser pulses is theoretically synthesized within the framework of optimal control theory (OCT) and employing the well-known pump-dump scheme of Tannor and Rice [D.J. Tannor, S.A. Rice, J. Chem. Phys. 83, 5013 (1985)]. In the OCT, the control task is framed as the maximization of cost functional defined in terms of an objective function along with the constraints on the field intensity and system dynamics. The latter is monitored by solving the time-dependent Schrödinger equation. The initial guess, laser driven dynamics and the optimized pulse structure (i.e., the spectral content and temporal profile) followed by associated mechanism involved in fulfilling the control task are examined in detail and discussed. A comparative account of the dynamical outcomes within the Condon approximation for the transition dipole moment versus its more realistic value calculated ab initio is also presented.

  10. Photoisomerization and Photoionization of the Photoactive Yellow Protein Chromophore in Solution

    PubMed Central

    Larsen, Delmar S.; Vengris, Mikas; van Stokkum, Ivo H. M.; van der Horst, Michael A.; de Weerd, Frank L.; Hellingwerf, Klaas J.; van Grondelle, Rienk

    2004-01-01

    Dispersed pump-dump-probe spectroscopy has the ability to characterize and identify the underlying ultrafast dynamical processes in complicated chemical and biological systems. This technique builds on traditional pump-probe techniques by exploring both ground- and excited-state dynamics and characterizing the connectivity between constituent transient states. We have used the dispersed pump-dump-probe technique to investigate the ground-state dynamics and competing excited-state processes in the excitation-induced ultrafast dynamics of thiomethyl p-coumaric acid, a model chromophore for the photoreceptor photoactive yellow protein. Our results demonstrate the parallel formation of two relaxation pathways (with multiple transient states) that jointly lead to two different types of photochemistry: cis-trans isomerization and detachment of a hydrated electron. The relative transition rates and quantum yields of both pathways have been determined. We find that the relaxation of the photoexcited chromophores involves multiple, transient ground-state intermediates and the chromophore in solution does not generate persistent photoisomerized products, but instead undergoes photoionization resulting in the generation of detached electrons and radicals. These results are of great value in interpreting the more complex dynamical changes in the optical properties of the photoactive yellow protein. PMID:15041690

  11. Weibel instability for a streaming electron, counterstreaming e-e, and e-p plasmas with intrinsic temperature anisotropy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ghorbanalilu, M.; Physics Department, Azarbaijan Shahid Madani University, Tabriz; Sadegzadeh, S.

    2014-05-15

    The existence of Weibel instability for a streaming electron, counterstreaming electron-electron (e-e), and electron-positron (e-p) plasmas with intrinsic temperature anisotropy is investigated. The temperature anisotropy is included in the directions perpendicular and parallel to the streaming direction. It is shown that the beam mean speed changes the instability mode, for a streaming electron beam, from the classic Weibel to the Weibel-like mode. The analytical and numerical solutions approved that Weibel-like modes are excited for both counterstreaming e-e and e-p plasmas. The growth rates of the instabilities in e-e and e-p plasmas are compared. The growth rate is larger for e-pmore » plasmas if the thermal anisotropy is small and the opposite is true for large thermal anisotropies. The analytical and numerical solutions are in good agreement only in the small parallel temperature and wave number limits, when the instability growth rate increases linearly with normalized wave number kc∕ω{sub p}.« less

  12. [Factors contributing to endemic cholera in Douala, Cameroon].

    PubMed

    Guévart, E; Noeske, J; Solle, J; Essomba, J M; Edjenguele, Mbonji; Bita, A; Mouangue, A; Manga, B

    2006-06-01

    Cholera has been endemic in Douala, Cameroon since 1971. A number of environmental factors favourize the survival of the Vibrio in Douala including location at the mouth of Wouri delta on the Atlantic Ocean, sandy clay soil, shallow dirty polluted foul-smelling groundwater, presence of vast expanses of swamp, streams/drainage ditches infested with algae, and high temperatures with low rainfall and drought during certain periods of the year. Most outbreaks have started in Bepanda, a slum area built on a garbage dump in a swampy zone fed by drainage ditches carrying the faecal pollution from neighbouring upstream districts. It is a densely overcrowded area of uncontrolled urbanization generated by the influx of poor city new-comers who live without adequate access to clean water or basic sanitary facilities. The most affected areas are those resulting from recent unregulated urban sprawl in polluted swamp zones or garbage dumps. Since access to the public water system is inadequate with only 65000 persons connected for 3 million inhabitants, dwellers in most areas must take water from the 70000 urban wells (estimated in 2004) that are often not more than 1.5 m deep. Sewage facilities are insufficient to provide complete evacuation of solid and liquid waste. The network of rivers, streams and man-made ditches waste are poorly maintained and often overflow during the rainy season. The contents of latrines are often discharged directly into the environment. Social factors such as the reformation of urban tribes and persistence of traditional attitudes toward waste disposal and water use have not only led to high-risk behaviour but also created barriers to sanitation and hygiene education. With an inadequate sanitation inspection system, a large but purely accessible public health system and a highly disorganized private health sector exists, effective preventive measures are difficult to implement. The combination of these factors probably account for the endemicity of cholera in Douala.

  13. 40 CFR 227.15 - Factors considered.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... could be used; (c) The relative environmental risks, impact and cost for ocean dumping as opposed to....15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Need for Ocean Dumping § 227.15...

  14. 40 CFR 227.15 - Factors considered.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... could be used; (c) The relative environmental risks, impact and cost for ocean dumping as opposed to....15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Need for Ocean Dumping § 227.15...

  15. 40 CFR 227.15 - Factors considered.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... could be used; (c) The relative environmental risks, impact and cost for ocean dumping as opposed to....15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Need for Ocean Dumping § 227.15...

  16. 40 CFR 227.15 - Factors considered.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... could be used; (c) The relative environmental risks, impact and cost for ocean dumping as opposed to....15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Need for Ocean Dumping § 227.15...

  17. 3-D RPIC simulations of relativistic jets: Particle acceleration, magnetic field generation, and emission

    NASA Technical Reports Server (NTRS)

    Nishikawa, K.-I.

    2006-01-01

    Nonthermal radiation observed from astrophysical systems containing (relativistic) jets and shocks, e.g., supernova remnants, active galactic nuclei (AGNs), gamma-ray bursts (GRBs), and Galactic microquasar systems usually have power-law emission spectra. Fermi acceleration is the mechanism usually assumed for the acceleration of particles in astrophysical environments. Recent PIC simulations using injected relativistic electron-ion (electro-positron) jets show that acceleration occurs within the downstream jet, rather than by the scattering of particles back and forth across the shock as in Fermi acceleration. Shock acceleration is a ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., the Buneman instability, other two-streaming instability, and the Weibel instability) created in the .shocks are responsible for particle (electron, positron, and ion) acceleration. The simulation results show that the Weibel instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields. These magnetic fields contribute to the electron's transverse deflection behind the jet head. The "jitter" radiation from deflected electrons has different properties than synchrotron radiation which is calculated in a uniform magnetic field. This jitter radiation may be important to understanding the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets, and supernova remnants. We will review recent PIC simulations which show particle acceleration in jets.

  18. 30 CFR 77.1608 - Dumping facilities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Dumping facilities. 77.1608 Section 77.1608 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... Haulage § 77.1608 Dumping facilities. (a) Dumping locations and haulage roads shall be kept reasonably...

  19. SM91: Observations of interchange between acceleration and thermalization processes in auroral electrons

    NASA Technical Reports Server (NTRS)

    Pongratz, M.

    1972-01-01

    Results from a Nike-Tomahawk sounding rocket flight launched from Fort Churchill are presented. The rocket was launched into a breakup aurora at magnetic local midnight on 21 March 1968. The rocket was instrumented to measure electrons with an electrostatic analyzer electron spectrometer which made 29 measurements in the energy interval 0.5 KeV to 30 KeV. Complete energy spectra were obtained at a rate of 10/sec. Pitch angle information is presented via 3 computed average per rocket spin. The dumped electron average corresponds to averages over electrons moving nearly parallel to the B vector. The mirroring electron average corresponds to averages over electrons moving nearly perpendicular to the B vector. The average was also computed over the entire downward hemisphere (the precipitated electron average). The observations were obtained in an altitude range of 10 km at 230 km altitude.

  20. Continuous-flow free acid monitoring method and system

    DOEpatents

    Strain, J.E.; Ross, H.H.

    1980-01-11

    A free acid monitoring method and apparatus is provided for continuously measuring the excess acid present in a process stream. The disclosed monitoring system and method is based on the relationship of the partial pressure ratio of water and acid in equilibrium with an acid solution at constant temperature. A portion of the process stream is pumped into and flows through the monitor under the influence of gravity and back to the process stream. A continuous flowing sample is vaporized at a constant temperature and the vapor is subsequently condensed. Conductivity measurements of the condensate produces a nonlinear response function from which the free acid molarity of the sample process stream is determined.

  1. Continuous-flow free acid monitoring method and system

    DOEpatents

    Strain, James E.; Ross, Harley H.

    1981-01-01

    A free acid monitoring method and apparatus is provided for continuously measuring the excess acid present in a process stream. The disclosed monitoring system and method is based on the relationship of the partial pressure ratio of water and acid in equilibrium with an acid solution at constant temperature. A portion of the process stream is pumped into and flows through the monitor under the influence of gravity and back to the process stream. A continuous flowing sample is vaporized at a constant temperature and the vapor is subsequently condensed. Conductivity measurements of the condensate produces a nonlinear response function from which the free acid molarity of the sample process stream is determined.

  2. Analytical modeling of flash-back phenomena. [premixed/prevaporized combustion system

    NASA Technical Reports Server (NTRS)

    Feng, C. C.

    1979-01-01

    To understand the flame flash-back phenomena more extensively, an analytical model was formed and a numerical program was written and tested to solve the set of differential equations describing the model. Results show that under a given set of conditions flame propagates in the boundary layer on a flat plate when the free stream is at or below 1.8 m/s.

  3. Reforming of fuel inside fuel cell generator

    DOEpatents

    Grimble, Ralph E.

    1988-01-01

    Disclosed is an improved method of reforming a gaseous reformable fuel within a solid oxide fuel cell generator, wherein the solid oxide fuel cell generator has a plurality of individual fuel cells in a refractory container, the fuel cells generating a partially spent fuel stream and a partially spent oxidant stream. The partially spent fuel stream is divided into two streams, spent fuel stream I and spent fuel stream II. Spent fuel stream I is burned with the partially spent oxidant stream inside the refractory container to produce an exhaust stream. The exhaust stream is divided into two streams, exhaust stream I and exhaust stream II, and exhaust stream I is vented. Exhaust stream II is mixed with spent fuel stream II to form a recycle stream. The recycle stream is mixed with the gaseous reformable fuel within the refractory container to form a fuel stream which is supplied to the fuel cells. Also disclosed is an improved apparatus which permits the reforming of a reformable gaseous fuel within such a solid oxide fuel cell generator. The apparatus comprises a mixing chamber within the refractory container, means for diverting a portion of the partially spent fuel stream to the mixing chamber, means for diverting a portion of exhaust gas to the mixing chamber where it is mixed with the portion of the partially spent fuel stream to form a recycle stream, means for injecting the reformable gaseous fuel into the recycle stream, and means for circulating the recycle stream back to the fuel cells.

  4. Reforming of fuel inside fuel cell generator

    DOEpatents

    Grimble, R.E.

    1988-03-08

    Disclosed is an improved method of reforming a gaseous reformable fuel within a solid oxide fuel cell generator, wherein the solid oxide fuel cell generator has a plurality of individual fuel cells in a refractory container, the fuel cells generating a partially spent fuel stream and a partially spent oxidant stream. The partially spent fuel stream is divided into two streams, spent fuel stream 1 and spent fuel stream 2. Spent fuel stream 1 is burned with the partially spent oxidant stream inside the refractory container to produce an exhaust stream. The exhaust stream is divided into two streams, exhaust stream 1 and exhaust stream 2, and exhaust stream 1 is vented. Exhaust stream 2 is mixed with spent fuel stream 2 to form a recycle stream. The recycle stream is mixed with the gaseous reformable fuel within the refractory container to form a fuel stream which is supplied to the fuel cells. Also disclosed is an improved apparatus which permits the reforming of a reformable gaseous fuel within such a solid oxide fuel cell generator. The apparatus comprises a mixing chamber within the refractory container, means for diverting a portion of the partially spent fuel stream to the mixing chamber, means for diverting a portion of exhaust gas to the mixing chamber where it is mixed with the portion of the partially spent fuel stream to form a recycle stream, means for injecting the reformable gaseous fuel into the recycle stream, and means for circulating the recycle stream back to the fuel cells. 1 fig.

  5. Sinuous Ridge on the Orson Welles Bajada

    NASA Image and Video Library

    2015-04-22

    Alluvial fans are piles of debris dumped by rivers when they emerge from the mountains and enter a mostly dry valley as seen by NASA Mars Reconnaissance Orbiter. A bajada (such as this example named after the famous American filmmaker) consists of a series of coalescing alluvial fans along a mountain front. On the surface of this bajada, one can see many sinuous ridges. These ridges mark the path that streams of water took as they flowed into this crater. The sinuosity of the ridges tells us something about the speed of the water flow. Fast moving flows tend to be straighter than slow-moving. Observations like this help us build a picture of how rivers behaved on ancient Mars. http://photojournal.jpl.nasa.gov/catalog/PIA19366

  6. Release of liquid water from the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Pike, C. P.; Knecht, D. J.; Viereck, R. A.; Murad, E.; Kofsky, I. L.; Bagian, J. P.; Buchli, J. F.

    1990-01-01

    Groundbased and onboard video images of a sunlit Shuttle Orbiter water dump are interpreted as showing that the continuous 1-mm-diameter liquid stream quickly breaks up in near-vacuum to form ice/snow particles of two characteristic sizes. Discrete large droplets are most evident in the close-in photographs, and unresolved submicron 'fog' from recondensation of overexpanded evaporated water appears to dominate the ground-telescope photographs of the 2.5 km long optically detectable trail. The mean diameter of the smaller particles was estimated from the spatial distribution of visible radiance using a model of their energy balance, (small) surface roughening as they sublime, and Mie scattering of pre-dawn sunlight. The results are consistent with those from recent space-tank simulations.

  7. 76 FR 33346 - Final Supplementary Rules for the Upper Snake Field Office, Idaho

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-08

    ... were placed at key locations in the greater planning area and contained comment cards that helped... prohibiting recreational vehicle (RV) owners from dumping their tanks at the dump station at Byington. The... prohibited from emptying their tanks in the dump station at Byington boat access. The capacity of the dump...

  8. 7 CFR 58.228 - Dump hoppers, screens, mixers and conveyors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Dump hoppers, screens, mixers and conveyors. 58.228... Service 1 Equipment and Utensils § 58.228 Dump hoppers, screens, mixers and conveyors. The product contact surfaces of dump hoppers, screens, mixers and conveyors which are used in the process of transferring dry...

  9. 40 CFR 223.1 - Contents of special, emergency, general, and research permits; posting requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CONTENTS OF PERMITS; REVISION, REVOCATION OR LIMITATION OF OCEAN DUMPING PERMITS UNDER SECTION 104(d) OF THE ACT Contents of Ocean Dumping Permits Issued... the assessment of the impact of permitted dumping activities on the marine environment at the disposal...

  10. 40 CFR 227.8 - Limitations on the disposal rates of toxic wastes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.8 Limitations on the disposal rates of toxic wastes. No wastes will be deemed acceptable for ocean dumping unless such wastes can be dumped so as not to exceed the limiting permissible...

  11. 40 CFR 223.1 - Contents of special, emergency, general, and research permits; posting requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CONTENTS OF PERMITS; REVISION, REVOCATION OR LIMITATION OF OCEAN DUMPING PERMITS UNDER SECTION 104(d) OF THE ACT Contents of Ocean Dumping Permits Issued... the assessment of the impact of permitted dumping activities on the marine environment at the disposal...

  12. 40 CFR 227.8 - Limitations on the disposal rates of toxic wastes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.8 Limitations on the disposal rates of toxic wastes. No wastes will be deemed acceptable for ocean dumping unless such wastes can be dumped so as not to exceed the limiting permissible...

  13. 40 CFR 227.8 - Limitations on the disposal rates of toxic wastes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.8 Limitations on the disposal rates of toxic wastes. No wastes will be deemed acceptable for ocean dumping unless such wastes can be dumped so as not to exceed the limiting permissible...

  14. 40 CFR 223.1 - Contents of special, emergency, general, and research permits; posting requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CONTENTS OF PERMITS; REVISION, REVOCATION OR LIMITATION OF OCEAN DUMPING PERMITS UNDER SECTION 104(d) OF THE ACT Contents of Ocean Dumping Permits Issued... the assessment of the impact of permitted dumping activities on the marine environment at the disposal...

  15. 40 CFR 223.1 - Contents of special, emergency, general, and research permits; posting requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CONTENTS OF PERMITS; REVISION, REVOCATION OR LIMITATION OF OCEAN DUMPING PERMITS UNDER SECTION 104(d) OF THE ACT Contents of Ocean Dumping Permits Issued... the assessment of the impact of permitted dumping activities on the marine environment at the disposal...

  16. 40 CFR 223.1 - Contents of special, emergency, general, and research permits; posting requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CONTENTS OF PERMITS; REVISION, REVOCATION OR LIMITATION OF OCEAN DUMPING PERMITS UNDER SECTION 104(d) OF THE ACT Contents of Ocean Dumping Permits Issued... the assessment of the impact of permitted dumping activities on the marine environment at the disposal...

  17. 40 CFR 227.8 - Limitations on the disposal rates of toxic wastes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.8 Limitations on the disposal rates of toxic wastes. No wastes will be deemed acceptable for ocean dumping unless such wastes can be dumped so as not to exceed the limiting permissible...

  18. 40 CFR 227.8 - Limitations on the disposal rates of toxic wastes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.8 Limitations on the disposal rates of toxic wastes. No wastes will be deemed acceptable for ocean dumping unless such wastes can be dumped so as not to exceed the limiting permissible...

  19. 7 CFR 46.22 - Accounting for dumped produce.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Accounting for dumped produce. 46.22 Section 46.22... Market Receivers § 46.22 Accounting for dumped produce. A clear and complete record shall be maintained... justifying dumping shall be forwarded to the consignor or joint account partner with the accounting and a...

  20. Formation of Mesoherpetobionts Communities on a Reclamated Coal Open Pit Dump

    NASA Astrophysics Data System (ADS)

    Luzyanin, Sergey; Eremeeva, Natalya

    2017-11-01

    The structure of the mesoherpetobionts arthropod communities of the reclamated dump of the Krasnobrodsky coal pit (Kemerovo region, Russia) has been studied. It was established that the pioneer grouping of mesoherpetobionts arthropod represented by classes of Chilopoda, Arachnida and Insecta-Ectognatha has been formed on the dump for two years after the soil deposition. From the Arachnida, the species of the order Aranei are the most active in the stocking of the dumps. From the class Chilopoda, the species of Lithobiomorpha appear the first on the dump. Insects from the following three orders, Heteroptera, Hymenoptera and especially Coleoptera take the main part in the expansion of dumps and the formation of primary communities. Among the Coleoptera, the beetles of the family of Carabidae (44 species, dynamic density 22.9 specimens/10 trapped per day) dominate. From them, small or medium-sized species are mainly involved in stocking the dumps. There are significant differences in the complexes of ground dump carabid beetles in comparison with the control group, differing in species composition of dominant species, species richness and species diversity parameters

  1. Contribution of the backstreaming ions to the self-magnetic pinch (SMP) diode current

    NASA Astrophysics Data System (ADS)

    Mazarakis, Michael G.; Bennett, Nichelle; Cuneo, Michael E.; Fournier, Sean D.; Johnston, Mark D.; Kiefer, Mark L.; Leckbee, Joshua J.; Nielsen, Dan S.; Oliver, Bryan V.; Sceiford, Matthew E.; Simpson, Sean C.; Renk, Timothy J.; Ruiz, Carlos L.; Webb, Timothy J.; Ziska, Derek; Droemer, Darryl W.; Gignac, Raymond E.; Obregon, Robert J.; Wilkins, Frank L.; Welch, Dale R.

    2018-04-01

    The results presented here were obtained with a self-magnetic pinch (SMP) diode mounted at the front high voltage end of the RITS accelerator. RITS is a Self-Magnetically Insulated Transmission Line (MITL) voltage adder that adds the voltage pulse of six 1.3 MV inductively insulated cavities. The RITS driver together with the SMP diode has produced x-ray spots of the order of 1 mm in diameter and doses adequate for the radiographic imaging of high area density objects. Although, through the years, a number of different types of radiographic electron diodes have been utilized with SABER, HERMES III and RITS accelerators, the SMP diode appears to be the most successful and simplest diode for the radiographic investigation of various objects. Our experiments had two objectives: first to measure the contribution of the back-streaming ion currents emitted from the anode target and second to try to evaluate the energy of those ions and hence the Anode-Cathode (A-K) gap actual voltage. In any very high voltage inductive voltage adder utilizing MITLs to transmit the power to the diode load, the precise knowledge of the accelerating voltage applied on the A-K gap is problematic. This is even more difficult in an SMP diode where the A-K gap is very small (˜1 cm) and the diode region very hostile. The accelerating voltage quoted in the literature is from estimates based on the measurements of the anode and cathode currents of the MITL far upstream from the diode and utilizing the para-potential flow theories and inductive corrections. Thus, it would be interesting to have another independent measurement to evaluate the A-K voltage. The diode's anode is made of a number of high-Z metals in order to produce copious and energetic flash x-rays. It was established experimentally that the back-streaming ion currents are a strong function of the anode materials and their stage of cleanness. We have measured the back-streaming ion currents emitted from the anode and propagating through a hollow cathode tip for various diode configurations and different techniques of target cleaning treatment: namely, heating at very high temperatures with DC and pulsed current, with RF plasma cleaning, and with both plasma cleaning and heating. We have also evaluated the A-K gap voltage by energy filtering technique. Experimental results in comparison with LSP simulations are presented.

  2. Ultrafast proton shuttling in Psammocora cyan fluorescent protein.

    PubMed

    Kennis, John T M; van Stokkum, Ivo H M; Peterson, Dayna S; Pandit, Anjali; Wachter, Rebekka M

    2013-09-26

    Cyan, green, yellow, and red fluorescent proteins (FPs) homologous to green fluorescent protein (GFP) are used extensively as model systems to study fundamental processes in photobiology, such as the capture of light energy by protein-embedded chromophores, color tuning by the protein matrix, energy conversion by Förster resonance energy transfer (FRET), and excited-state proton transfer (ESPT) reactions. Recently, a novel cyan fluorescent protein (CFP) termed psamFP488 was isolated from the genus Psammocora of reef building corals. Within the cyan color class, psamFP488 is unusual because it exhibits a significantly extended Stokes shift. Here, we applied ultrafast transient absorption and pump-dump-probe spectroscopy to investigate the mechanistic basis of psamFP488 fluorescence, complemented with fluorescence quantum yield and dynamic light scattering measurements. Transient absorption spectroscopy indicated that, upon excitation at 410 nm, the stimulated cyan emission rises in 170 fs. With pump-dump-probe spectroscopy, we observe a very short-lived (110 fs) ground-state intermediate that we assign to the deprotonated, anionic chromophore. In addition, a minor fraction (14%) decays with 3.5 ps to the ground state. Structural analysis of homologous proteins indicates that Glu-167 is likely positioned in sufficiently close vicinity to the chromophore to act as a proton acceptor. Our findings support a model where unusually fast ESPT from the neutral chromophore to Glu-167 with a time constant of 170 fs and resulting emission from the anionic chromophore forms the basis of the large psamFP488 Stokes shift. When dumped to the ground state, the proton on neutral Glu is very rapidly shuttled back to the anionic chromophore in 110 fs. Proton shuttling in excited and ground states is a factor of 20-4000 faster than in GFP, which probably results from a favorable hydrogen-bonding geometry between the chromophore phenolic oxygen and the glutamate acceptor, possibly involving a short hydrogen bond. At any time in the reaction, the proton is localized on either the chromophore or Glu-167, which implies that most likely no low-barrier hydrogen bond exists between these molecular groups. This work supports the notion that proton transfer in biological systems, be it in an electronic excited or ground state, can be an intrinsically fast process that occurs on a 100 fs time scale. PsamFP488 represents an attractive model system that poses an ultrafast proton transfer regime in discrete steps. It constitutes a valuable model system in addition to wild type GFP, where proton transfer is relatively slow, and the S65T/H148D GFP mutant, where the effects of low-barrier hydrogen bonds dominate.

  3. New views of the Gulf Stream

    NASA Astrophysics Data System (ADS)

    Todd, R. E.

    2016-02-01

    The Gulf Stream plays a major role in the climate system and is a significant forcing agent for the coastal circulation along the US East Coast, yet routine subsurface measurements of Gulf Stream structure are only collected in the Florida Straits and between New Jersey and Bermuda. A recent pilot program demonstrated the feasibility of using underwater gliders to repeatedly survey across the Gulf Stream and to provide subsurface Gulf Stream observations to the community in realtime. Spray gliders were deployed on three-month missions from Miami, Florida to the New England shelf south of Cape Cod, during which they zigzagged back and forth across the Gulf Stream. Three such deployments have been completed so far with a total of more than 20 cross-Gulf Stream transects occupied. These new observations detail the subsurface structure and variability of the Gulf Stream upstream and downstream of its separation from the continental margin, reveal large-amplitude internal waves within the boundary current, and capture numerous eddies along the flanks of the Gulf Stream. Future routine glider deployments in the Gulf Stream promise to provide critical observations for examining inherent Gulf Stream variability, investigating western boundary current influences on coastal circulation, and constraining numerical simulations.

  4. An experimental study on dredge spoil of estuarine sediments in the bay of seine (France): A morphosedimentary assessment

    NASA Astrophysics Data System (ADS)

    Marmin, Stella; Lesueur, Patrick; Dauvin, Jean Claude; Samson, Sandrine; Tournier, Patrice; Gallicher Lavanne, Albert; Dubrulle-Brunaud, Carole; Thouroude, Coralie

    2016-03-01

    Studies on the consequences of dredging on estuarine morphology and its sedimentary dynamics are common, but the impacts of dumping dredge spoil in coastal open settings are rarely found in scientific literature. An experimental study was conducted over the period 2012-2013 to monitor the physical impacts of dredged material dumped at two adjacent sites (one million cubic metres at each) on the inner shelf of the Bay of Seine in France (eastern part of the English Channel, La Manche). As recently reinforced in the EU Marine Strategy Framework Directive (MSFD), knowledge on the location and intensity of human impacts (e.g. on marine ecosystems) is critical for effective marine management and conservation. So, two methods of disposition were tested to evaluate the impacts of dumping on the environment and thus propose recommendations for future dumping. The strategy is based on a Before-After-Control-Impact (BACI) approach, in which the spatio-temporal variability was studied by analysing the morphological and sedimentological characteristics over a period of 28 months, from November 2011 to April 2014, also including recovery of the seafloor after cessation of the dumping activities. The first experimental dumping operation (MASED) was carried out regularly for 8 months at a single point and generating a conical deposit of 5 m in height, while the second dumping (MABIO) lasted for 12 months involving four steps in the dumping process. In the second case, a wider area was covered, leading to the formation of a smaller deposit of 2 m in height. The dumped deposits consisted of muddy fine sand, whereas the inner shelf seafloor in this area is covered with fine to medium sand. As a result, muddy fine sand accumulated at or near the two dumping sites, with a maximum mud (i.e. particles<63 μm or>4 Φ) content of 50% compared to<5% before dumping operations. Videos obtained from a LVB200 Seabotix ROV, highlighted the heterogeneity of the sea floor around the dumping areas. Due to hydrodynamic forcing (wave climate and tidal currents), about 50% (MABIO) and 75% (MASED) of the volume of dredged material remained at the end of the dumping periods. After dumping ceased, a further 5% of material for MABIO and 20% for MASED, was transported out of the study area. For the latter, a spreading of fine particles was observed extending from the conical deposit towards the south west. To favour long-term exploitation, a more dispersive dumping over a wider surface area is recommended (e.g. MABIO)

  5. Parasitic Diseases: Glossary

    MedlinePlus

    ... from swimming pools, hot tubs, Jacuzzis, spas, fountains, lakes, rivers, springs, ponds, streams, or the ocean. Recreational ... contact with contaminated water from swimming pools, spas, lakes, rivers, or the ocean. Back To Top (https:// ...

  6. Electron heating within interaction zones of simple high-speed solar wind streams

    NASA Technical Reports Server (NTRS)

    Feldman, W. C.; Asbridge, J. R.; Bame, S. J.; Gosling, J. T.; Lemons, D. S.

    1978-01-01

    In the present paper, electron heating within the high-speed portions of three simple stream-stream interaction zones is studied to further our understanding of the physics of heat flux regulation in interplanetary space. To this end, the thermal signals present in the compressions at the leading edges of the simple high-speed streams are analyzed, showing that the data are inconsistent with the Spitzer conductivity. Instead, a polynomial law is found to apply. Its implication concerning the mechanism of interplanetary heat conduction is discussed, and the results of applying this conductivity law to high-speed flows inside of 1 AU are studied. A self-consistent model of the radial evolution of electrons in the high-speed solar wind is proposed.

  7. Somatostatin and the dumping syndrome.

    PubMed

    Long, R G; Adrian, T E; Bloom, S R

    1985-03-23

    Infusion of somatostatin reduced the symptoms of the early dumping syndrome after oral glucose was given and also reduced the associated tachycardia and rise in packed cell volume. It inhibited the secretion of enteroglucagon, neurotensin, and vasoactive intestinal polypeptide, which are raised in patients with the dumping syndrome and may have an aetiological role. It also prevented the reactive hypoglycaemia of late dumping by inhibiting the release of gastric inhibitory polypeptide and insulin. Somatostatin, possibly through its inhibitory effects on hormonal secretion, may have a role in the management of patients with the early and late dumping syndrome.

  8. Impact of waste dump on surface water quality and aquatic insect diversity of Deepor Beel (Ramsar site), Assam, North-east India.

    PubMed

    Choudhury, Dharitri; Gupta, Susmita

    2017-10-06

    Water and aquatic insects were collected seasonally from site 1, the low-lying area of the dump near Deepor Beel, and from sites 2 and 3 of the main wetland and analysed. While dissolved oxygen (DO) increased from site 1 to site 3 in each season, electrical conductivity (EC), total dissolved solid (TDS), total alkalinity (TA) and free CO 2 (F-CO 2 ) decreased. Pb and Cd were found to exceed the limits set for drinking water in all the sites and seasons. Species richness (SpR) was found highest (23) at site 2 and lowest (14) at site 1. Sensitive species was absent. The Shannon (H') values at site 1 were < 1 while at sites 2 and 3 were > 1 in most of the seasons. Biological monitoring scores (Biological Monitoring Working Party and Stream Invertebrate Grade Number-Average Level) in different sites and seasons inferred severely poor to moderate water quality. At site 1, significant negative correlations were seen for Pb and Cr with SpR while Ni and Cu with insect density (ID). At site 2, TA had highly significant positive correlations with SpR and ID while Cu showed negative correlation with SpR. At site 3, ID had significant negative relationships with air temperature, water temperature, depth, TA, F-CO 2 , PO 4 3- and Cr. Canonical correspondence analysis triplot has clearly separated site 1 associated with tolerant species and highly influenced by TA, TDS, EC, F-CO 2, Cr, Ni, Cd and Zn confirming high anthropogenic activities on that site. Tolerant and semitolerant species were present at site 2 (influenced by depth and transparency) and site 3 (influenced by Pb and WT) both. Results of this study discerned that the dump site is the point source of pollution.

  9. X-ray emitting MHD accretion shocks in classical T Tauri stars. Case for moderate to high plasma-β values

    NASA Astrophysics Data System (ADS)

    Orlando, S.; Sacco, G. G.; Argiroffi, C.; Reale, F.; Peres, G.; Maggio, A.

    2010-02-01

    Context. Plasma accreting onto classical T Tauri stars (CTTS) is believed to impact the stellar surface at free-fall velocities, generating a shock. Current time-dependent models describing accretion shocks in CTTSs are one-dimensional, assuming that the plasma moves and transports energy only along magnetic field lines (β ≪ 1). Aims: We investigate the stability and dynamics of accretion shocks in CTTSs, considering the case of β ⪆ 1 in the post-shock region. In these cases the 1D approximation is not valid and a multi-dimensional MHD approach is necessary. Methods: We model an accretion stream propagating through the atmosphere of a CTTS and impacting onto its chromosphere by performing 2D axisymmetric MHD simulations. The model takes into account the stellar magnetic field, the gravity, the radiative cooling, and the thermal conduction (including the effects of heat flux saturation). Results: The dynamics and stability of the accretion shock strongly depend on the plasma β. In the case of shocks with β > 10, violent outflows of shock-heated material (and possibly MHD waves) are generated at the base of the accretion column and intensely perturb the surrounding stellar atmosphere and the accretion column itself (therefore modifying the dynamics of the shock). In shocks with β ≈ 1, the post-shock region is efficiently confined by the magnetic field. The shock oscillations induced by cooling instability are strongly influenced by β: for β > 10, the oscillations may be rapidly dumped by the magnetic field, approaching a quasi-stationary state, or may be chaotic with no obvious periodicity due to perturbation of the stream induced by the post-shock plasma itself; for β≈ 1 the oscillations are quasi-periodic, although their amplitude is smaller and the frequency higher than those predicted by 1D models. Three movies are only available in electronic form at http://www.aanda.org

  10. Development of KSTAR Thomson scattering system.

    PubMed

    Lee, J H; Oh, S T; Wi, H M

    2010-10-01

    To measure the electron temperature (T(e)) and electron density (n(e)) profiles in the Korean Superconducting Tokamak Advanced Research (KSTAR) device for the KSTAR third campaign (September 2010), we designed and installed a Thomson scattering system. The KSTAR Thomson scattering system is designed as a tangential Thomson scattering system and utilizes the N-, L-, and B-ports. The N-port is designed for the collection optics with a cassette system, the L-port is the laser input port, and the B-port is the location of the beam dump. In this paper, we will describe the final design of the KSTAR Thomson scattering system.

  11. A 15,000-hour cyclic endurance test of an 8-centimeter-diameter electron bombardment mercury ion thruster

    NASA Technical Reports Server (NTRS)

    Nakanishi, S.

    1976-01-01

    A laboratory model 8-cm thruster with improvements to minimize ion chamber erosion and peeling of sputtered metal was subjected to a cyclic endurance test for 15,040 hours and 460 restarts. A charted history of several thruster operating variables and off-normal events are shown in 600-hour segments at three points in the test. The transient behavior of these variables during a typical start-stop cycle is presented. Performance and operating characteristics were nearly constant throughout the test except for a change in the accelerator back-streaming limit. Findings of the post-test inspection confirmed most of the expected results. Charge-exchange ions caused normal accelerator grid erosion. The workability of the various design features have been substantiated, and attainable improvements in propellant utilization efficiency should significantly reduce accelerator erosion.

  12. Environmental and economic analyses of waste disposal options for traditional markets in Indonesia.

    PubMed

    Aye, Lu; Widjaya, E R

    2006-01-01

    Waste from traditional markets in Indonesia is the second largest stream of municipal solid waste after household waste. It has a higher organic fraction and may have greater potential to be managed on a business scale compared to household wastes. The attributed reason is that in general the wastes generated from traditional markets are more uniform, more concentrated and less hazardous than waste from other sources. This paper presents the results of environmental and economic assessments to compare the options available for traditional market waste disposal in Indonesia. The options compared were composting in labour intensive plants, composting in a centralised plant that utilised a simple wheel loader, centralised biogas production and landfill for electricity production. The current open dumping practice was included as the baseline case. A life cycle assessment (LCA) was used for environmental analysis. All options compared have lower environmental impacts than the current practice of open dumping. The biogas production option has the lowest environmental impacts. A cost-benefit analysis, which considered greenhouse gas savings, was used for the economic assessment. It was found that composting at a centralised plant is the most economically feasible option under the present Indonesian conditions. The approach reported in this study could be applied for 'a pre-feasibility first cut comparison' that includes environmental aspects in a decision-making framework for developing countries even though European emission factors were used.

  13. Risk assessment predictions of open dumping area after closure using Monte Carlo simulation

    NASA Astrophysics Data System (ADS)

    Pauzi, Nur Irfah Mohd; Radhi, Mohd Shahril Mat; Omar, Husaini

    2017-10-01

    Currently, there are many abandoned open dumping areas that were left without any proper mitigation measures. These open dumping areas could pose serious hazard to human and pollute the environment. The objective of this paper is to determine the risk assessment at the open dumping area after they has been closed using Monte Carlo Simulation method. The risk assessment exercise is conducted at the Kuala Lumpur dumping area. The rapid urbanisation of Kuala Lumpur coupled with increase in population lead to increase in waste generation. It leads to more dumping/landfill area in Kuala Lumpur. The first stage of this study involve the assessment of the dumping area and samples collections. It followed by measurement of settlement of dumping area using oedometer. The risk of the settlement is predicted using Monte Carlo simulation method. Monte Carlo simulation calculates the risk and the long-term settlement. The model simulation result shows that risk level of the Kuala Lumpur open dumping area ranges between Level III to Level IV i.e. between medium risk to high risk. These settlement (ΔH) is between 3 meters to 7 meters. Since the risk is between medium to high, it requires mitigation measures such as replacing the top waste soil with new sandy gravel soil. This will increase the strength of the soil and reduce the settlement.

  14. Monitoring of Thermal and Gas Activities in Mining Dump Hedvika, Czech Republic

    NASA Astrophysics Data System (ADS)

    Surovka, D.; Pertile, E.; Dombek, V.; Vastyl, M.; Leher, V.

    2017-10-01

    The negative consequences of mining of the black coal is occurrence of extractive waste storage locations - mining dumps. The mining activities carried out within the area of Ostrava are responsible for at least six mine dumps of loose materials arising as wastes from mining of mineral resources, many of which show presence of thermal processes. The thermal activity in dumps is responsible for many hazardous substances that pollute the environment and harm human health in the surroundings. This paper deals with the results of the first phase of project CZ.11.4.120/0.0/0.0/15_006/0000074 TERDUMP, on exploration of thermally active mining dumps are published in the article. As a first studied thermally active dump was a Hedvika dump. To localize of hot spots with hot gas emission was used a thermovision scanning by drone. The place with high temperature (49.8 °C) identified natural gas emission through natural cracks. Analysing the occurring pollutants in Hedvika Dump using the GC-MS or HPLC, respectively and the inert gases (CO2, CO and SO2) were determined by ion chromatography. The pollutants were determined in five sampling points during two measurements executed from July to August 2017.

  15. Curling Prominence

    NASA Image and Video Library

    2017-12-18

    A small prominence observed in profile arched up and sent streams of plasma curling back into the sun over a 30-hour period (Dec. 13-14, 2017). We are observing charged particles streaming along magnetic field lines made visible in extreme ultraviolet light. Prominences are cooler strands of plasma tethered above the sun's surface by magnetic forces. They are quite unstable and frequently fall apart within hours or days. Movies are available at https://photojournal.jpl.nasa.gov/catalog/PIA22196

  16. PATHOPHYSIOLOGY, DIAGNOSIS AND TREATMENTOF DUMPING SYNDROME AND ITS RELATION TO BARIATRIC SURGERY

    PubMed Central

    CHAVES, Yasmin da Silva; DESTEFANI, Afrânio Côgo

    2016-01-01

    ABSTRACT Introduction The dumping syndrome is frequent in bariatric surgery. It is probably the most common syndrome following partial or complete gastrectomy. Its prevalence in partial gastrectomy can reach up to 50%, thus it can be a significant complication arising from some types of bariatric surgeries. Objective: Critical analysis on dumping syndrome, its pathophysiology, diagnosis and treatment. Methods: A literature review was performed using the key words: 'dumping syndrome', 'bariatric surgery' and 'rapid dumping syndrome'. Inclusion criteria were: books, original works, case reports and meta-analyzes, and the exclusion criterion was literature review. Concerning the publication time, articles were screened between 1960 and May 2015. Results: The dumping syndrome is complication arising from obesity surgeries, but also can be a result of vagus nerve damage. Diagnosis is done primarily through the use of questionnaires based on scores. Conclusion: The Sigstad score and Arts survey are valid means for assessing the dumping syndrome. Initial therapy consists in the adoption of dietary measures, short acting drugs administration. PMID:27683791

  17. 30 CFR 57.9301 - Dump site restraints.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Loading, Hauling, and Dumping Safety Devices, Provisions, and Procedures for Roadways, Railroads, and Loading and Dumping Sites...

  18. Somatostatin and the dumping syndrome.

    PubMed Central

    Long, R G; Adrian, T E; Bloom, S R

    1985-01-01

    Infusion of somatostatin reduced the symptoms of the early dumping syndrome after oral glucose was given and also reduced the associated tachycardia and rise in packed cell volume. It inhibited the secretion of enteroglucagon, neurotensin, and vasoactive intestinal polypeptide, which are raised in patients with the dumping syndrome and may have an aetiological role. It also prevented the reactive hypoglycaemia of late dumping by inhibiting the release of gastric inhibitory polypeptide and insulin. Somatostatin, possibly through its inhibitory effects on hormonal secretion, may have a role in the management of patients with the early and late dumping syndrome. PMID:2858244

  19. Use of ultrafast dispersed pump-dump-probe and pump-repump-probe spectroscopies to explore the light-induced dynamics of peridinin in solution.

    PubMed

    Papagiannakis, Emmanouil; Vengris, Mikas; Larsen, Delmar S; van Stokkum, Ivo H M; Hiller, Roger G; van Grondelle, Rienk

    2006-01-12

    Optical pump-induced dynamics of the highly asymmetric carotenoid peridinin in methanol was studied by dispersed pump-probe, pump-dump-probe, and pump-repump-probe transient absorption spectroscopy in the visible region. Dispersed pump-probe measurements show that the decay of the initially excited S2 state populates two excited states, the S1 and the intramolecular charge-transfer (ICT) state, at a ratio determined by the excitation wavelength. The ensuing spectral evolution occurs on the time scale of a few picoseconds and suggests the equilibration of these states. Dumping the stimulated emission of the ICT state with an additional 800-nm pulse after 400- and 530-nm excitation preferentially removes the ICT state contribution from the broad excited-state absorption, allowing for its spectral characterization. At the same time, an unrelaxed ground-state species, which has a subpicosecond lifetime, is populated. The application of the 800-nm pulse at early times, when the S2 state is still populated, led to direct generation of the peridinin cation, observed for the first time in a transient absorption experiment. The excited and ground electronic states manifold of peridinin has been reconstructed using target analysis; this approach combined with the measured multipulse spectroscopic data allows us to estimate the spectra and time scales of the corresponding transient states.

  20. Analysis of Geodynamical Conditions of Region of Burning Coal Dumps Location

    NASA Astrophysics Data System (ADS)

    Batugin, Andrian; Musina, Valeria; Golovko, Irina

    2017-12-01

    Spontaneous combustion of coal dumps and their impact on the environment of mining regions remain important environmental problem, in spite of the measures that are being taken. The paper presents the hypothesis, which states that the location of coal dumps at the boundaries of geodynamically active crust blocks promotes the appearance of conditions for their combustion. At present geodynamically active crust faults that affect the operating conditions of engineering facilities are observed not only in the areas of tectonic activity, but also on platforms. According to the concept of geodynamical zoning, geodynamically dangerous zones for engineering structures can be not only large, well-developed crust faults, but also just formed fractures that appear as boundaries of geodynamically impacting and hierarchically ordered crust blocks. The purpose of the study is to estimate the linkage of burning dumps to boundaries of geodynamically active crust blocks (geodynamically dangerous zones) for subsequent development of recommendations for reducing environmental hazard. The analysis of 27 coal dumps location was made for one of the Eastern Donbass regions (Russia). Nine of sixteen burning dumps are located in geodynamically dangerous zones, which, taking into account relatively small area occupied by all geodynamically dangerous zones, results that there is a concentration (pcs/km2) of burning dumps, which is 14 times higher than the baseline value. While the probability of accidental obtaining of such a result is extremely low, this can be considered as the evidence of the linkage of burning dumps to geodynamically dangerous zones. Taking into account the stressed state of the rock massif in this region, all geodynamically dangerous zones can be divided into compression and tension zones. The statistic is limited, but nevertheless in tension zones the concentration of burning dumps is 2 times higher than in compression zones. Available results of thermal monitoring of burning dumps in this region also show that linearly extended firing sources oriented along geodynamically dangerous zones are observed. The obtained results show that geodynamical conditions of mining region, in which coal dumps are located, is important factor that impacts the creation of conditions for their spontaneous combustion and subsequent impact on the environment. Then this factor should be controlled by choosing the place for dumps location. It is proposed to carry out these works for the entire mining region of the Eastern Donbass, where there are more than 200 coal dumps.

  1. River and Stream Pollution

    MedlinePlus

    ... downstream clean, too. Other stuff you might like ... Games & Puzzles Games galore! Piles of Puzzles! Go! What's That Word ... and classroom materials. Back to Top Check out games and songs for little kids! Topics Games Activities ...

  2. Compact turbidity meter

    NASA Technical Reports Server (NTRS)

    Hirschberg, J. G.

    1979-01-01

    Proposed monitor that detects back-reflected infrared radiation makes in situ turbidity measurements of lakes, streams, and other bodies of water. Monitor is compact, works well in daylight as at night, and is easily operated in rough seas.

  3. Evidence of locally enhanced target heating due to instabilities of counter-streaming fast electron beams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koester, Petra; Cecchetti, Carlo A.; Booth, Nicola

    2015-02-15

    The high-current fast electron beams generated in high-intensity laser-solid interactions require the onset of a balancing return current in order to propagate in the target material. Such a system of counter-streaming electron currents is unstable to a variety of instabilities such as the current-filamentation instability and the two-stream instability. An experimental study aimed at investigating the role of instabilities in a system of symmetrical counter-propagating fast electron beams is presented here for the first time. The fast electron beams are generated by double-sided laser-irradiation of a layered target foil at laser intensities above 10{sup 19 }W/cm{sup 2}. High-resolution X-ray spectroscopy ofmore » the emission from the central Ti layer shows that locally enhanced energy deposition is indeed achieved in the case of counter-propagating fast electron beams.« less

  4. Passive energy dump for superconducting coil protection

    DOEpatents

    Luton, J.N. Jr.

    1973-01-16

    The patent describes a passive resistance type energy dump for the protection of the coils of a superconducting magnet. Insertion heaters are immersed in a rigid container filled with a fusible alloy. The energy dump is connected across the coils of the superconducting magnet wherein individual heater elements are connected singly to the windings or otherwise according to the energy dumping requirements upon transition of the magnet to a normal state.

  5. D0 Superconducting Solenoid Quench Data and Slow Dump Data Acquisition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Markley, D.; /Fermilab

    1998-06-09

    This Dzero Engineering note describes the method for which the 2 Tesla Superconducting Solenoid Fast Dump and Slow Dump data are accumulated, tracked and stored. The 2 Tesla Solenoid has eleven data points that need to be tracked and then stored when a fast dump or a slow dump occur. The TI555(Texas Instruments) PLC(Programmable Logic Controller) which controls the DC power circuit that powers the Solenoid, also has access to all the voltage taps and other equipment in the circuit. The TI555 constantly logs these eleven points in a rotating memory buffer. When either a fast dump(dump switch opens) ormore » a slow dump (power supply turns off) occurs, the TI555 organizes the respective data and will down load the data to a file on DO-CCRS2. This data in this file is moved over ethernet and is stored in a CSV (comma separated format) file which can easily be examined by Microsoft Excel or any other spreadsheet. The 2 Tesla solenoid control system also locks in first fault information. The TI555 decodes the first fault and passes it along to the program collecting the data and storing it on DO-CCRS2. This first fault information is then part of the file.« less

  6. The uninsured and patient dumping: recent policy responses in indigent care.

    PubMed Central

    Rice, M. F.; Jones, W.

    1991-01-01

    This article discusses the uninsured population and the phenomenon known as "patient dumping"--the transfer of a patient from one hospital (typically a private hospital) to a public hospital because of the patient's lack of insurance or inability to pay. The uninsured are the most vulnerable to patient dumping. The growth of patient dumping, a profile of the uninsured who are most likely to be a minority, and an analysis of federal and state policy responses to patient dumping are all discussed. The need for reform of the American health care system is highlighted and the Canadian health system is suggested as an alternative model. PMID:1800761

  7. Physics and engineering design of the accelerator and electron dump for SPIDER

    NASA Astrophysics Data System (ADS)

    Agostinetti, P.; Antoni, V.; Cavenago, M.; Chitarin, G.; Marconato, N.; Marcuzzi, D.; Pilan, N.; Serianni, G.; Sonato, P.; Veltri, P.; Zaccaria, P.

    2011-06-01

    The ITER Neutral Beam Test Facility (PRIMA) is planned to be built at Consorzio RFX (Padova, Italy). PRIMA includes two experimental devices: a full size ion source with low voltage extraction called SPIDER and a full size neutral beam injector at full beam power called MITICA. SPIDER is the first experimental device to be built and operated, aiming at testing the extraction of a negative ion beam (made of H- and in a later stage D- ions) from an ITER size ion source. The main requirements of this experiment are a H-/D- extracted current density larger than 355/285 A m-2, an energy of 100 keV and a pulse duration of up to 3600 s. Several analytical and numerical codes have been used for the design optimization process, some of which are commercial codes, while some others were developed ad hoc. The codes are used to simulate the electrical fields (SLACCAD, BYPO, OPERA), the magnetic fields (OPERA, ANSYS, COMSOL, PERMAG), the beam aiming (OPERA, IRES), the pressure inside the accelerator (CONDUCT, STRIP), the stripping reactions and transmitted/dumped power (EAMCC), the operating temperature, stress and deformations (ALIGN, ANSYS) and the heat loads on the electron dump (ED) (EDAC, BACKSCAT). An integrated approach, taking into consideration at the same time physics and engineering aspects, has been adopted all along the design process. Particular care has been taken in investigating the many interactions between physics and engineering aspects of the experiment. According to the 'robust design' philosophy, a comprehensive set of sensitivity analyses was performed, in order to investigate the influence of the design choices on the most relevant operating parameters. The design of the SPIDER accelerator, here described, has been developed in order to satisfy with reasonable margin all the requirements given by ITER, from the physics and engineering points of view. In particular, a new approach to the compensation of unwanted beam deflections inside the accelerator and a new concept for the ED have been introduced.

  8. 15. CAR DUMP BUILDING, DETAIL SHOWING GRATES OVER COAL BINS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. CAR DUMP BUILDING, DETAIL SHOWING GRATES OVER COAL BINS AND CABLES UNDER CAR DUMP CONTROL HOUSE - Pennsylvania Railroad, Canton Coal Pier, Clinton Street at Keith Avenue (Canton area), Baltimore, Independent City, MD

  9. Three-Level De-Multiplexed Dual-Branch Complex Delta-Sigma Transmitter.

    PubMed

    Arfi, Anis Ben; Elsayed, Fahmi; Aflaki, Pouya M; Morris, Brad; Ghannouchi, Fadhel M

    2018-02-20

    In this paper, a dual-branch topology driven by a Delta-Sigma Modulator (DSM) with a complex quantizer, also known as the Complex Delta Sigma Modulator (CxDSM), with a 3-level quantized output signal is proposed. By de-multiplexing the 3-level Delta-Sigma-quantized signal into two bi-level streams, an efficiency enhancement over the operational frequency range is achieved. The de-multiplexed signals drive a dual-branch amplification block composed of two switch-mode back-to-back power amplifiers working at peak power. A signal processing technique known as quantization noise reduction with In-band Filtering (QNRIF) is applied to each of the de-multiplexed streams to boost the overall performances; particularly the Adjacent Channel Leakage Ratio (ACLR). After amplification, the two branches are combined using a non-isolated combiner, preserving the efficiency of the transmitter. A comprehensive study on the operation of this topology and signal characteristics used to drive the dual-branch Switch-Mode Power Amplifiers (SMPAs) was established. Moreover, this work proposes a highly efficient design of the amplification block based on a back-to-back power topology performing a dynamic load modulation exploiting the non-overlapping properties of the de-multiplexed Complex DSM signal. For experimental validation, the proposed de-multiplexed 3-level Delta-Sigma topology was implemented on the BEEcube™ platform followed by the back-to-back Class-E switch-mode power amplification block. The full transceiver is assessed using a 4th-Generation mobile communications standard LTE (Long Term Evolution) standard 1.4 MHz signal with a peak to average power ratio (PAPR) of 8 dB. The dual-branch topology exhibited a good linearity and a coding efficiency of the transmitter chain higher than 72% across the band of frequency from 1.8 GHz to 2.7 GHz.

  10. Creation of high-energy electron tails by means of the modified two-stream instability

    NASA Technical Reports Server (NTRS)

    Tanaka, M.; Papadopoulos, K.

    1983-01-01

    Particle simulations of the modified two-stream instability demonstrate strong electron acceleration rather than bulk heating when the relative drift speed is below a critical speed Vc. A very interesting nonlinear mode transition and autoresonance acceleration process is observed which accelerates the electrons much above the phase speed of the linearly unstable modes. Simple criteria are presented that predict the value of Vc and the number density of the accelerated electrons.

  11. Particle Acceleration, Magnetic Field Generation and Emission from Relativistic Jets

    NASA Technical Reports Server (NTRS)

    Nishikawa, K.-I.; Hardee, P.; Hededal, C.; Mizuno, Yosuke; Fishman, G. Jerry; Hartmann, D. H.

    2006-01-01

    Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks, e.g., active galactic nuclei (AGNs), gamma-ray bursts (GRBs), supernova remnants, and Galactic microquasar systems usually have power-law emission spectra. Fermi acceleration is the mechanism usually assumed for the acceleration of particles in astrophysical environments. Recent PIC simulations using injected relativistic electron-ion (electro-positron) jets show that particle acceleration occurs within the downstream jet, rather than by the scattering of particles back and forth across the shock as in Fermi acceleration. Shock acceleration' is a ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., the Buneman instability, other two-streaming instability, and the Weibel instability) created in the shocks are responsible for particle (electron, positron, and ion) acceleration. The simulation results show that the Weibel instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields. These magnetic fields contribute to the electron's transverse deflection behind the jet head. The "jitter" radiation from deflected electrons has different spectral properties than synchrotron radiation which is calculated in a uniform magnetic field. This jitter radiation may be important to understanding the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets, and supernova remnants. We will review recent PIC simulations of relativistic jets and try to make a connection with observations.

  12. The influence of solar active region evolution on solar wind streams, coronal hole boundaries and geomagnetic storms

    NASA Technical Reports Server (NTRS)

    Gold, R. E.; Dodson-Prince, H. W.; Hedeman, E. R.; Roelof, E. C.

    1982-01-01

    Solar and interplanetary data are examined, taking into account the identification of the heliographic longitudes of the coronal source regions of high speed solar wind (SW) streams by Nolte and Roelof (1973). Nolte and Roelof have 'mapped' the velocities measured near earth back to the sun using the approximation of constant radial velocity. The 'Carrington carpet' for rotations 1597-1616 is shown in a graph. Coronal sources of high speed streams appear in the form of solid black areas. The contours of the stream sources are laid on 'evolutionary charts' of solar active region histories for the Southern and Northern Hemispheres. Questions regarding the interplay of active regions and solar wind are investigated, giving attention to developments during the years 1973, 1974, and 1975.

  13. A/R systems reduce delayed and denied reimbursements.

    PubMed

    Escobar, Carlos

    2007-01-01

    The day-to-day benefits of a comprehensive billing and collections system are pro-active and preventive--administrators are increasingly learning that accelerating billings hastens collections and, ultimately, facility profitability. Effective billing and collections management services work closely with the facility, matching nightly "dumps" of patient files with transcripts. This marriage of otherwise disparate data creates a billing unit that reduces errors and ensures no billable procedures are lost. Ultimately, the goal of any medical practice that engages an ASP application or outsource solution is not to sit idly by while allowing a billing company to take control of a practice's revenue stream. The ability to track the billing process from transcript submission to payment provides a facility with all information necessary to manage cash flow, revenues, and even personal and practice financial planning.

  14. Using social knowledge networking technology to enable meaningful use of electronic health record technology in hospitals and health systems.

    PubMed

    Rangachari, Pavani

    2014-12-01

    Despite the federal policy momentum towards "meaningful use" of Electronic Health Records, the healthcare organizational literature remains replete with reports of unintended adverse consequences of implementing Electronic Health Records, including: increased work for clinicians, unfavorable workflow changes, and unexpected changes in communication patterns & practices. In addition to being costly and unsafe, these unintended adverse consequences may pose a formidable barrier to "meaningful use" of Electronic Health Records. Correspondingly, it is essential for hospital administrators to understand and detect the causes of unintended adverse consequences, to ensure successful implementation of Electronic Health Records. The longstanding Technology-in-Practice framework emphasizes the role of human agency in enacting structures of technology use or "technologies-in-practice." Given a set of unintended adverse consequences from health information technology implementation, this framework could help trace them back to specific actions (types of technology-in-practice) and institutional conditions (social structures). On the other hand, the more recent Knowledge-in-Practice framework helps understand how information and communication technologies ( e.g. , social knowledge networking systems) could be implemented alongside existing technology systems, to create new social structures, generate new knowledge-in-practice, and transform technology-in-practice. Therefore, integrating the two literature streams could serve the dual purpose of understanding and overcoming unintended adverse consequences of Electronic Health Record implementation. This paper seeks to: (1) review the theoretical literatures on technology use & implementation, and identify a framework for understanding & overcoming unintended adverse consequences of implementing Electronic Health Records; (2) outline a broad project proposal to test the applicability of the framework in enabling "meaningful use" of Electronic Health Records in a healthcare context; and (3) identify strategies for successful implementation of Electronic Health Records in hospitals & health systems, based on the literature review and application.

  15. Exploring Ultrafast Structural Dynamics for Energetic Enhancement or Disruption

    DTIC Science & Technology

    2016-03-01

    it. In a pump -push/ dump probe experiment, a secondary laser pulse (push/ dump ) is used after the initial perturbation due to the pump pulse. The...increased. The pump -push/ dump probe technique is a difficult experiment that requires a highly stable laser source. Ultrafast pump -probe experiments...decomposition of solids. Journal of Applied Physics. 2001;89:4156–4166. 17. Kee TW. Femtosecond pump -push-probe and pump - dump -probe spectroscopy of

  16. Efficiency of Low-Profile External Dumping at Open Pit Coal Mining in Kemerovo Region

    NASA Astrophysics Data System (ADS)

    Selyukov, Alexey; Ermolaev, Vyacheslav; Kostinez, Irina

    2017-11-01

    Kemerovo region is one of the largest industrial regions of Russia, with a raw material specialization. The rapid growth of the coal industry in recent years has been greatly facilitated by the expansion and development of open pit mining for coal seams extraction, accompanied by an increase in the volumes of overburden and the height of the dumps. There are about 400 objects in the Russian Federation Government Register of Waste Disposal Facilities 80% of which are dumps. Approaches both to external dumping and to the technical stage of reclamation currently contribute to the growth of geomorphic system's instability. Thus, it is proposed to slightly change the approaches to external dumping: the essence consists in the formation of an external dump of overburden, which in future would represent a favorable landscape unit of a flat surface relief used for subsequent differently directed purposes.

  17. EMERGING TECHNOLOGY BULLETIN: ELECTRON BEAM TREATMENT FOR THE REMOVAL OF BENZENE AND TOULENE FROM AQUEOUS STREAMS AND SLUDGES

    EPA Science Inventory

    The electron accelerator utilized in this treatment process has a potential of 1.5 MeV, rated from 0 to 50 mA, providing radiation doses of 0-850 krad (0-8.5 kGy). The horizontal electron beam is scanned at 200 Hz and impacts the waste stream as it flows over a weir approximately...

  18. Apparatus and methods for regeneration of precipitating solvent

    DOEpatents

    Liu, Guohai; Vimalchand, Pannalal; Peng, Wan Wang; Bonsu, Alexander

    2015-08-25

    A regenerator that can handle rich loaded chemical solvent containing precipitated absorption reaction products is disclosed. The invention is particularly suitable for separating CO.sub.2 from large gas streams that are typical of power plant processes. The internally circulating liquid stream in the regenerator (ICLS regenerator) rapidly heats-up the in-coming rich solvent stream in a downcomer standpipe as well as decreases the overall concentration of CO.sub.2 in the mixed stream. Both these actions lead to dissolution of precipitates. Any remaining precipitate further dissolves as heat is transferred to the mixed solution with an inverted bayonet tube heat exchanger in the riser portion of the regenerator. The evolving CO.sub.2 bubbles in the riser portion of the regenerator lead to substantial gas hold-up and the large density difference between the solutions in the downcomer standpipe and riser portions promotes internal circulation of the liquid stream in the regenerator. As minor amounts of solvent components present in the exit gas stream are condensed and returned back to the regenerator, pure CO.sub.2 gas stream exits the disclosed regenerator and condenser system.

  19. Photo-electronic current transport in back-gated graphene transistor

    NASA Astrophysics Data System (ADS)

    Srivastava, Ashok; Chen, Xinlu; Pradhan, Aswini K.

    2017-04-01

    In this work, we have studied photo-electronic current transport in a back-gated graphene field-effect transistor. Under the light illumination, band bending at the metal/graphene interface develops a built-in potential which generates photonic current at varying back-gate biases. A typical MOSFET type back-gated transistor structure uses a monolayer graphene as the channel layer formed over the silicon dioxide/silicon substrate. It is shown that the photo-electronic current consists of current contributions from photovoltaic, photo-thermoelectric and photo-bolometric effects. A maximum external responsivity close to 0.0009A/W is achieved at 30μW laser power source and 633nm wavelength.

  20. Tracking of the nuclear wavepacket motion in cyanine photoisomerization by ultrafast pump-dump-probe spectroscopy.

    PubMed

    Wei, Zhengrong; Nakamura, Takumi; Takeuchi, Satoshi; Tahara, Tahei

    2011-06-01

    Understanding ultrafast reactions, which proceed on a time scale of nuclear motions, requires a quantitative characterization of the structural dynamics. To track such structural changes with time, we studied a nuclear wavepacket motion in photoisomerization of a prototype cyanine dye, 1,1'-diethyl-4,4'-cyanine, by ultrafast pump-dump-probe measurements in solution. The temporal evolution of wavepacket motion was examined by monitoring the efficiency of stimulated emission dumping, which was obtained from the recovery of a ground-state bleaching signal. The dump efficiency versus pump-dump delay exhibited a finite rise time, and it became longer (97 fs → 330 fs → 390 fs) as the dump pulse was tuned to longer wavelengths (690 nm → 950 nm → 1200 nm). This result demonstrates a continuous migration of the leading edge of the wavepacket on the excited-state potential from the Franck-Condon region toward the potential minimum. A slowly decaying feature of the dump efficiency indicated a considerable broadening of the wavepacket over a wide range of the potential, which results in the spread of a population distribution on the flat S(1) potential energy surface. The rapid migration as well as broadening of the wavepacket manifests a continuous nature of the structural dynamics and provides an intuitive visualization of this ultrafast reaction. We also discussed experimental strategies to evaluate reliable dump efficiencies separately from other ultrafast processes and showed a high capability and possibility of the pump-dump-probe method for spectroscopic investigation of unexplored potential regions such as conical intersections. © 2011 American Chemical Society

  1. Role of Feshbach resonances in enhancing the production of deeply bound ultracold LiRb molecules with laser pulses

    NASA Astrophysics Data System (ADS)

    Gacesa, Marko; Ghosal, Subhas; Côté, Robin

    2010-03-01

    We investigate the possibility of forming deeply bound LiRb molecules in a two-color photoassociation experiment. Ultracold ^6Li and ^87Rb atoms colliding in the vicinity of a magnetic Feshbach resonance are photoassociated into an excited electronic state. A wavepacket is then formed by exciting a few vibrational levels of the excited state and allowed to propagate. We calculate the time-dependent overlaps between the wave packet and the lowest vibrational levels of the ground state. After the optimal overlap is obtained we use the second laser pulse to dump the wave packet and efficiently populate the deeply bound ro-vibrational levels of ^6Li^87Rb in the ground state. The resulting combination of Feshbach-optimized photoassociation (FOPA) with the time-dependent pump-dump approach will produce a large number of stable ultracold molecules in the ground state. This technique is general and applicable to other systems.

  2. Incoherent manipulation of the photoactive yellow protein photocycle with dispersed pump-dump-probe spectroscopy.

    PubMed

    Larsen, Delmar S; van Stokkum, Ivo H M; Vengris, Mikas; van Der Horst, Michael A; de Weerd, Frank L; Hellingwerf, Klaas J; van Grondelle, Rienk

    2004-09-01

    Photoactive yellow protein is the protein responsible for initiating the "blue-light vision" of Halorhodospira halophila. The dynamical processes responsible for triggering the photoactive yellow protein photocycle have been disentangled with the use of a novel application of dispersed ultrafast pump-dump-probe spectroscopy, where the photocycle can be started and interrupted with appropriately tuned and timed laser pulses. This "incoherent" manipulation of the photocycle allows for the detailed spectroscopic investigation of the underlying photocycle dynamics and the construction of a fully self-consistent dynamical model. This model requires three kinetically distinct excited-state intermediates, two (ground-state) photocycle intermediates, I(0) and pR, and a ground-state intermediate through which the protein, after unsuccessful attempts at initiating the photocycle, returns to the equilibrium ground state. Also observed is a previously unknown two-photon ionization channel that generates a radical and an ejected electron into the protein environment. This second excitation pathway evolves simultaneously with the pathway containing the one-photon photocycle intermediates.

  3. Incoherent Manipulation of the Photoactive Yellow Protein Photocycle with Dispersed Pump-Dump-Probe Spectroscopy

    PubMed Central

    Larsen, Delmar S.; van Stokkum, Ivo H. M.; Vengris, Mikas; van der Horst, Michael A.; de Weerd, Frank L.; Hellingwerf, Klaas J.; van Grondelle, Rienk

    2004-01-01

    Photoactive yellow protein is the protein responsible for initiating the “blue-light vision” of Halorhodospira halophila. The dynamical processes responsible for triggering the photoactive yellow protein photocycle have been disentangled with the use of a novel application of dispersed ultrafast pump-dump-probe spectroscopy, where the photocycle can be started and interrupted with appropriately tuned and timed laser pulses. This “incoherent” manipulation of the photocycle allows for the detailed spectroscopic investigation of the underlying photocycle dynamics and the construction of a fully self-consistent dynamical model. This model requires three kinetically distinct excited-state intermediates, two (ground-state) photocycle intermediates, I0 and pR, and a ground-state intermediate through which the protein, after unsuccessful attempts at initiating the photocycle, returns to the equilibrium ground state. Also observed is a previously unknown two-photon ionization channel that generates a radical and an ejected electron into the protein environment. This second excitation pathway evolves simultaneously with the pathway containing the one-photon photocycle intermediates. PMID:15345564

  4. A study of contaminated soils near Crucea-Botus, ana uranium mine (East Carpathians, Romania): metal distribution and partitioning of natural actinides with implications for vegetation uptake

    NASA Astrophysics Data System (ADS)

    Petrescu, L.; Bilal, E.

    2012-04-01

    Between 1962 and 2009, National Company of Uranium - CNU, the former Romanian Rare Metals Mining Company, mined over 1,200,000 tones of pitchblende ore in the East Carpathians (Crucea-Botušana area, Bistrita Mountains). The exploration and mining facilities include 32 adits, situated between 780 and 1040 m above sea level. Radioactive waste resulted from mining are disposed next to the mining facilities. Mine dumps (32) cover an area of 364,000 square meters and consist of waste rock (rocks with sub-economic mineralization) and gangue minerals. Older dumps (18) have been already naturally reclaimed by forest vegetation, which played an important role in stabilizing the waste dump cover and in slowing down the uranium migration processes. The soils samples have been collected from different mine dumps in the Crucea-Botušana uranium deposit, mainly from 1, 4, 5, 6, 8, 9, 1/30 and 950 mine waste galleries. Soil samples were collected from the upper part and slope at each mine dump, from the vegetation root zones. Total uranium concentration in soils collected from Crucea-Botušana site ranged from 6.10 to 680.70 ppm, with a mean of 52.48 ppm (dry wt.). Total thorium varies between 7.70 and 115.30 ppm (dry wt.). This indicates that the adsorption of the radioactive elements by the soils is high and variable, influenced by the ore dump - sample relationship. The sequential extraction has emphasized the fact that the uranium is associated with all the mineral fractions present in the soil samples. A great percentage of U can be found in the carbonate (21.77%), organic (15.04%) and oxides fractions (15.88%) - in accordance with the high absorbed/adsorbed properties of this element. The percentage of uranium detected in the exchangeable fraction is rather small - 2.16%. It is also to be expected that the uranium should be irreversible adsorbed by the organic matter and by the clay minerals due to its ionic radius and to its positive charge. The fact that 21.77% of the total uranium can be found in the specifically absorbed and carbonate bound fraction, indicated the important role played by the carbonates in the retention of U; one the other hand this fraction is liable to release the uranium if the pH should happen to change. Thorium appear in high-enough concentration in the soil is scarcely available because 70.29% is present in residual fraction, and about 21.78% in the crystalline iron oxides occluded fraction and organically and secondary sulfide bound fraction. This is certainly due to the fact that this naturally occurring radionuclide can be associated with relatively insoluble mineral phases like alumino-silicates and refractory oxides. Its association with the organic matter (10.93%) suggests that it can form soluble organic complexes that can facilitate its removal by the stream waters. Grounded on these results, we were able to prove that the examined mine dumps can represent an impact on the environment, which constitute an argument in favor of the initiation of a program of remedying the quality of the environment from this mining zone. Although from our research it resulted that the natural actinides does not concentrate in the exchangeable fraction (Th) or it concentrates very little in it (U), the isolation of the mineral fraction of soil rich in U and Th helps us in the future identification of the links between the bioavailability and the pedogenesis, connections which control the cycle of the radioactive metals.

  5. Mapping Of Construction Waste Illegal Dumping Using Geographical Information System (GIS)

    NASA Astrophysics Data System (ADS)

    Zainun, Noor Yasmin; Rahman, Ismail Abdul; Azwana Rothman, Rosfazreen

    2016-11-01

    Illegal dumping of solid waste not only affecting the environment but also social life of communities, hence authorities should have an effective system to cater this problem. Malaysia is experiencing extensive physical developments and this has led to an increase of construction waste illegal dumping. However, due to the lack of proper data collection, the actual figure for construction waste illegal dumping in Malaysia are not available. This paper presents a mapping of construction waste illegal dumping in Kluang district, Johor using Geographic Information System (GIS) software. Information of the dumped waste such as coordinate, photos, types of material and quantity of waste were gathered manually through site observation for three months period. For quantifying the dumped waste, two methods were used which are the first method is based on shape of the waste (pyramids or squares) while the second method is based weighing approach. All information regarding the waste was assigned to the GIS for the mapping process. Results indicated a total of 12 types of construction waste which are concrete, tiles, wood, gypsum board, mixed construction waste, brick and concrete, bricks, sand, iron, glass, pavement and tiles, and concrete at 64 points locations of illegal dumping on construction waste in Kluang. These wastes were accounted to an estimated volume of 427.2636 m3. Hopefully, this established map will assist Kluang authority to improve their solid waste management system in Kluang.

  6. Confinement time of electron plasma approaching magnetic pumping transport limit in small aspect ratio C-shaped torus

    NASA Astrophysics Data System (ADS)

    Lachhvani, Lavkesh; Pahari, Sambaran; Goswami, Rajiv; Bajpai, Manu; Yeole, Yogesh; Chattopadhyay, P. K.

    2016-06-01

    A long confinement time of electron plasma, approaching magnetic pumping transport limit, has been observed in SMARTEX-C (a small aspect ratio partial torus with R o / a ˜ 1.59 ). Investigations of the growth rate reveal that they are governed by instabilities like resistive wall destabilization, ion driven instabilities, and electron-neutral collisions. Successful confinement of electron plasmas exceeding > 1 × 10 5 poloidal E → × B → rotations lasting for nearly 2.1 ± 0.1 s is achieved by suppressing these instabilities. The confinement time has been estimated in two ways: (a) from the frequency scaling of the linear diocotron mode launched from sections of the wall that are also used as capacitive probes and (b) by dumping the plasma onto a charge collector at different hold times.

  7. 40 CFR 227.12 - Insoluble wastes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.12... ocean environment may be generally approved for ocean dumping provided they are insoluble above the...

  8. 40 CFR 227.12 - Insoluble wastes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.12... ocean environment may be generally approved for ocean dumping provided they are insoluble above the...

  9. 40 CFR 227.12 - Insoluble wastes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.12... ocean environment may be generally approved for ocean dumping provided they are insoluble above the...

  10. 40 CFR 227.12 - Insoluble wastes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.12... ocean environment may be generally approved for ocean dumping provided they are insoluble above the...

  11. Preliminary Cultural Resource Survey and Geomorphological Assessment of Selected Areas in Navigation Pool 16, Mississippi River.

    DTIC Science & Technology

    1982-06-01

    Dated Sites in Pool 16 .............. 28 OR 2. Stream Gauge Data for Historical - Floods, Illinois and Mississippi Canal Lock 32 (U. S. Corps of...the ridge was 30 TABLE 2 STREAM GAUGE DATA FOR HISTORICAL FLOODS, ILLINOIS AND MISSISSIPPI CANAL LOCK 32 (U. S. CORPS OF ENGINEERS 1981) Rank Order of...result of back- water activity rather than active throughflow similar to that experienced in the 1890s. Judging from river gauge records dating from

  12. Evidence of Atlantic salmon Salmo salar fry movement between fresh water and a brackish environment.

    PubMed

    Taal, I; Rohtla, M; Saks, L; Svirgsden, R; Kesler, M; Matetski, L; Vetemaa, M

    2017-08-01

    This study reports descent of Atlantic salmon Salmo salar fry from their natal streams to brackish waters of the Baltic Sea and their use of this environment as an alternative rearing habitat before ascending back to freshwater streams. To the authors' knowledge, residency in a brackish environment has not previously been demonstrated in S. salar fry. Recruitment success and evolutionary significance of this alternative life-history strategy are presently not known. © 2017 The Fisheries Society of the British Isles.

  13. Environmental impact assessment of sediment dumping in the southern Baltic Sea using meiofaunal indicators

    NASA Astrophysics Data System (ADS)

    Frenzel, Peter; Borrmann, Corinna; Lauenburg, Beate; Bohling, Björn; Bartholdy, Jan

    2009-02-01

    An experimental sediment dumping was carried out in the southern part of the Mecklenburg Bight in June 2001. Foraminiferans and ostracods from superficial sandy sediment were studied in a time series from before dumping until March 2004 in order to assess changes in associations and recolonization patterns of both groups. Additionally, an area sampling covering the dumping site and its surroundings from 15.5 to 20.7 m water depth made it possible to compare associations inside and outside the dumping area as well as the water depth dependent distribution of foraminiferans and ostracods. Salinity values vary within the high alpha-mesohaline and low polyhaline range. The dominating species are Ammotium cassis (Foraminifera) and Sarsicytheridea bradii (Ostracoda). The diversity is low (Fisher alpha index from 0.4 to 3.2 for foraminiferans and 1.0 to 2.5 for ostracods), but higher within the dumping site samples. These higher values are explainable by input of allochthonous tests and valves representing additional species. After the sediment dumping it took two and a half years to re-establish the total foraminiferan association and the total foraminifer/ostracod ratio within the dumping site. Total foraminiferan abundance increases remarkably with water depth (mean 83 tests in 100 ml) driven by higher nutrient availability and more suitable salinity and temperature values within the zone of the oscillating halocline. The distribution of shallow water species such as Cribroelphidium excavatum, Eucythere argus and Hirschmannia viridis, within the transient water layer A. cassis, Nodulina dentaliniformis, S. bradii and Palmoconcha laevata and below Eggerella scabra indicate the depth position of the halocline. Water depth and sediment dumping influence are the main driving factors for the distribution of foraminifer and ostracod associations within the study area. However, a significant sedimentological difference between samples inside and outside the dumping area is not recognizable.

  14. A framework to preserve the privacy of electronic health data streams.

    PubMed

    Kim, Soohyung; Sung, Min Kyoung; Chung, Yon Dohn

    2014-08-01

    The anonymization of health data streams is important to protect these data against potential privacy breaches. A large number of research studies aiming at offering privacy in the context of data streams has been recently conducted. However, the techniques that have been proposed in these studies generate a significant delay during the anonymization process, since they concentrate on applying existing privacy models (e.g., k-anonymity and l-diversity) to batches of data extracted from data streams in a period of time. In this paper, we present delay-free anonymization, a framework for preserving the privacy of electronic health data streams. Unlike existing works, our method does not generate an accumulation delay, since input streams are anonymized immediately with counterfeit values. We further devise late validation for increasing the data utility of the anonymization results and managing the counterfeit values. Through experiments, we show the efficiency and effectiveness of the proposed method for the real-time release of data streams. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Kinetics of selenium release in mine waste from the Meade Peak Phosphatic Shale, Phosphoria Formation, Wooley Valley, Idaho, USA

    USGS Publications Warehouse

    Stillings, Lisa L.; Amacher, Michael C.

    2010-01-01

    Phosphorite from the Meade Peak Phosphatic Shale member of the Permian Phosphoria Formation has been mined in southeastern Idaho since 1906. Dumps of waste rock from mining operations contain high concentrations of Se which readily leach into nearby streams and wetlands. While the most common mineralogical residence of Se in the phosphatic shale is elemental Se, Se(0), Se is also an integral component of sulfide phases (pyrite, sphalerite and vaesite–pyritess) in the waste rock. It may also be present as adsorbed selenate and/or selenite, and FeSe2 and organo-selenides.Se release from the waste rock has been observed in field and laboratory experiments. Release rates calculated from waste rock dump and column leachate solutions describe the net, overall Se release from all of the possible sources of Se listed above. In field studies, Se concentration in seepage water (pH 7.4–7.8) from the Wooley Valley Unit 4 dump ranges from 3600 µg/L in May to 10 µg/L by Sept. Surface water flow, Q, from the seep also declines over the summer, from 2 L/s in May to 0.03 L/s in Sept. Se flux ([Se] ⁎ Q) reaches a steady-state of < 150 mg/day in 1–4 months, depending upon the volume of Q. Se release (mg/L) follows a first order reaction with a rate constant, k, = 1.35 – 6.35e−3 h− 1 (11.8–55.6 yr− 1).Laboratory experiments were performed with the waste shale in packed bed reactors; residence time varied from 0.09 to 400 h and outlet pH ∼ 7.5. Here, Se concentration increased with increasing residence time and release was modeled with a first order reaction with k = 2.19e−3 h− 1 (19.2 yr− 1).Rate constants reported here fall within an order of magnitude of reported rate constants for oxidation of Se(0) formed by bacterial precipitation. This similarity among rate constants from both field and laboratory studies combined with the direct observation of Se(0) in waste shales of the Phosphoria Formation suggests that oxidation of Se(0) may control steady-state Se concentration in water draining the Wooley Valley waste dump.

  16. 50 CFR 85.11 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... increase the value of usefulness of existing property. Dump station. A facility specifically designed to receive sewage from portable toilets carried on vessels. Dump stations do not include lavatories or... pumpout and dump stations. Eligible applicant. An agency of a State designated by the Governor. Equitable...

  17. 40 CFR 227.5 - Prohibited materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ....5 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.5 Prohibited materials. The ocean dumping of the following materials will not be approved by EPA or the Corps...

  18. 40 CFR 227.17 - Basis for determination.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 227.17 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Impact of the Proposed Dumping on Esthetic, Recreational and Economic Values § 227.17 Basis for determination. (a) The impact of...

  19. ANNUAL REPORT TO CONGRESS ON OCEAN DUMPING

    EPA Science Inventory

    This Report to Congress covers calendar years 1987 through Fiscal Year 1990 Activities covered include EPA’s implementation of the Marine Protection, Research, and Sanctuaries Act (MPRSA) and the 1988 amendment, the Ocean Dumping Ban Act (ODBA). ODBA makes the dumping of mu...

  20. Particle damping applied research on mining dump truck vibration control

    NASA Astrophysics Data System (ADS)

    Song, Liming; Xiao, Wangqiang; Guo, Haiquan; Yang, Zhe; Li, Zeguang

    2018-05-01

    Vehicle vibration characteristics has become an important evaluation indexes of mining dump truck. In this paper, based on particle damping technology, mining dump truck vibration control was studied by combining the theoretical simulation with actual testing, particle damping technology was successfully used in mining dump truck cab vibration control. Through testing results analysis, with a particle damper, cab vibration was reduced obviously, the methods and basis were provided for vehicle vibration control research and particle damping technology application.

  1. Resilience Analysis of Face Slopes and Internal Dumps and Causes of their Instability at “Mugunsky” Opencast Coal Mine

    NASA Astrophysics Data System (ADS)

    Zagibalov, A. V.; Okhotin, A. L.; Volokhov, A. V.

    2017-10-01

    The paper deals with the problems of initiation and consequences of landslide processes registered in the internal dumps at Mugunsky lignite opencast mine. Water cutting at the internal dump base, availability of clay rocks in the dump bottom, and the bottom incline towards the working face are revealed to be the sources of the landslide process. Some measures are recommended to prevent deformation processes that are possible to take place in the run of mine development.

  2. A summary of the test procedures and operational details of an ocean dumping pollution monitoring experiment conducted 7 October 1976

    NASA Technical Reports Server (NTRS)

    Hypes, W. D.; Wallace, J. W.; Gurganus, E. A.

    1977-01-01

    A remote sensor experiment was conducted at a sewage sludge dump site off the Delaware/Maryland coast. Two aircraft serving as remote sensor platforms flew over the dump site during a sludge dump. One aircraft carried a multispectral scanner and the other aircraft carried a rapid scanning spectrometer. Data from sea-truth stations were collected concurrent with overpasses of the aircraft. All sensors were operational and produced good digital data.

  3. Hydrogeology, water quality, and potential for transport of organochlorine pesticides in ground water at the North Hollywood Dump, Memphis, Tennessee

    USGS Publications Warehouse

    Broshears, R.E.; Bradley, M.W.

    1992-01-01

    Geologic, hydrologic, and water-quality data indicate that ground-water contamination is confined to shallow horizons within the unconfined aquifer underlying the North Hollywood Dump in Memphis, Tennessee. The dump is a closed municipal-industrial landfill that has been ranked as Tennessee's potentially most dangerous hazardous-waste site. Toxic constituents of concern at the dump include residues from the manufacture of organochlorine pesticides. The dump overlies an unconfined aquifer of unconsolidated sands, silts, and clays. During average hydrologic conditions, ground waterflows beneath the dump at a mean velocity of approximately 3 feet per day and discharges to the Wolf River. Leachate from the dump mixes with underlying ground water, resulting in increased concentrations of dissolved solids and organic carbon downgradient from the dump. The mobility of chlordane, a representative organochlorine pesticide, is limited by its low solubility and its strong affinity for sand, silt, and clays of the aquifer. Degradation of chlordane may occur slowly, if at all, in the aquifer. Based on estimates of mean ground-water velocity and retardation of the pesticide due to sorption, mean travel times for chlordane migrating from the dump to the ground-water discharge zone are of the order of 50 to 500 years. Simulations of chlordane concentration resulting from the discharge of contaminated ground water and complete mixing in the Wolf River are sensitive to assumptions about chlordane persistence in the unconfined aquifer. If the half life of chlordane in the aquifer is assumed to be 30 years or less, the simulated concentration of chlordane in the Wolf River under average flow conditions is less than the most stringent water-quality criterion.

  4. Bioaccumulation of organochlorines in crows from an indian open waste dumping site: evidence for direct transfer of dioxin-like congeners from the contaminated soil.

    PubMed

    Watanabe, Michio X; Iwata, Hisato; Watanabe, Mafumi; Tanabe, Shinsuke; Subramanian, Annamalai; Yoneda, Kumiko; Hashimoto, Takuma

    2005-06-15

    To assess the significance of waste dumping sites as a source of chemical contamination to ecosystems, we analyzed the residue levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and other organochlorines in the breast muscle of crows from a dumping site in the south of Chennai city, South India. Crows from the dumping site contained significantly higher total TEQs (60 +/- 27 pg/g lipid wt) than those from the reference sites (26 +/- 18 pg/g lipid wt). Especially, certain dioxin-like coplanar PCB congeners (Co-PCBs), such as CB-77 and CB-105, whose source is commercial PCBs,were significantly higher in crows from the dumping site than those from the reference sites. Profiles of PCDDs/DFs and Co-PCBs in crows from the dumping site were similar to those of soil at the same site, which was confirmed by principal component analysis. Furthermore, significant positive correlations were obtained between the congener-specific bioconcentration factors (BCFs) of PCDDs/DFs estimated from concentrations in crows and soil from the dumping site and the theoretical BCFs calculated from water-particle and lipid-water partitioning coefficients. On the other hand, the estimated BCFs had significant negative correlations with the molecular weight of PCDDs/DFs, indicating that molecular size limits their bioaccumulation. These results suggest that dioxin-like congeners in the soil of the dumping site were transferred directly to the crows through the ingestion of on-site garbage contaminated with soil, rather than through trophic transfer in the ecosystem. The present study provides insight into the ecological impacts of dumping sites.

  5. On the use of electrokinetic phenomena of the second kind for probing electrode kinetic properties of modified electron-conducting surfaces.

    PubMed

    Duval, Jérôme F L; Sorrenti, Estelle; Waldvogel, Yves; Görner, Tatiana; De Donato, Philippe

    2007-04-14

    The electrokinetic features of electron-conducting substrates, as measured in a conventional thin-layer electrokinetic cell, strongly depend on the extent of bipolar faradaic depolarisation of the interface formed with the adjacent electrolytic solution. Streaming potential versus applied pressure data obtained for metallic substrates must generally be interpreted on the basis of a modified Helmholtz-Smoluchowski equation corrected by an electronic conduction term-non linear with respect to the lateral potential and applied pressure gradient-that stems from the bipolar electrodic behavior of the metallic surface. In the current study, streaming potential measurements have been performed in KNO(3) solutions on porous plugs made of electron-conducting grains of pyrite (FeS(2)) covered by humic acids. For zero coverage, the extensive bipolar electronic conduction taking place in the plug-depolarized by concomitant and spatially distributed oxidation and reduction reactions of Fe(2+) and Fe(3+) species-leads to the complete extinction of the streaming potential over the entire range of applied pressure examined. For low to intermediate coverage, the local electron-transfer kinetics on the covered regions of the plug becomes more sluggish. The overall bipolar electronic conduction is then diminished which leads to an increase in the streaming potential with a non-linear dependence on the pressure. For significant coverage, a linear response is observed which basically reflects the interfacial double layer properties of the humics surface layer. A tractable, semi-analytical model is presented that reproduces the electrokinetic peculiarities of the complex and composite system FeS(2)/humics investigated. The study demonstrates that the streaming potential technique is a fast and valuable tool for establishing how well the electron transfer kinetics at a partially or completely depolarised bare electron-conducting substrate/electrolyte solution interface is either promoted (catalysis) or blocked (passivation) by the presence of a discontinuous surface layer.

  6. Thermal device and method for production of carbon monoxide and hydrogen by thermal dissociation of hydrocarbon gases

    DOEpatents

    Detering, Brent A.; Kong, Peter C.

    2001-01-01

    Carbon monoxide is produced in a fast quench reactor. The production of carbon monoxide includes injecting carbon dioxide and some air into a reactor chamber having a high temperature at its inlet and a rapidly expanding a reactant stream, such as a restrictive convergent-divergent nozzle at its outlet end. Carbon dioxide and other reactants such as methane and other low molecular weight hydrocarbons are injected into the reactor chamber. Other gas may be added at different stages in the process to form a desired end product and prevent back reactions. The resulting heated gaseous stream is then rapidly cooled by expansion of the gaseous stream.

  7. ION PULSE GENERATION

    DOEpatents

    King, R.F.; Moak, C.D.; Parker, V.E.

    1960-10-11

    A device for generating ions in an ion source, forming the ions into a stream, deflecting the stream rapidly away from and back to its normal path along the axis of a cylindrical housing, and continually focusing the stream by suitable means into a sharp, intermittent beam along the axis is described. The beam exists through an axial aperture into a lens which focuses it into an accelerator tube. The ions in each burst are there accelerated to very high energies and are directed against a target placed in the high-energy end of the tube. Radiations from the target can then be analyzed in the interval between incidence of the bursts of ions on the target.

  8. 50 CFR 85.30 - Grant selection criteria.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... constructing and renovating pumpout and dump stations without an approved plan; (c) In coastal States, proposals for constructing and renovating pumpout and dump stations in accordance with a coastal State's... constructing and renovating pumpout and dump stations in accordance with an inland State's plan; (d) Proposals...

  9. Which Disc Player for Education? A Comparative Evaluation.

    ERIC Educational Resources Information Center

    Leveridge, Leo L.; Lyons, David S.

    1983-01-01

    Advantages and disadvantages of videodisc players using digital program dumps are discussed. Indicates that, although digital dumps on videodiscs can be used to deliver interactive audiovisual programs about as effectively as external computer programs, disadvantages greatly outweigh advantages. Thus, digital program dumps recorded on videodiscs…

  10. 40 CFR 223.3 - Preliminary determination; notice.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....3 Section 223.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CONTENTS OF PERMITS; REVISION, REVOCATION OR LIMITATION OF OCEAN DUMPING PERMITS UNDER SECTION 104(d) OF THE ACT Procedures for Revision, Revocation or Limitation of Ocean Dumping Permits Under Section 104(d...

  11. 40 CFR 227.5 - Prohibited materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 227.5 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.5 Prohibited materials. The ocean dumping of the following materials will not be approved by EPA or the Corps...

  12. 40 CFR 227.4 - Criteria for evaluating environmental impact.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... impact. 227.4 Section 227.4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental... impact prohibitions, limits, and conditions for the dumping of materials into ocean waters. If the...

  13. 40 CFR 227.5 - Prohibited materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 227.5 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.5 Prohibited materials. The ocean dumping of the following materials will not be approved by EPA or the Corps...

  14. 40 CFR 223.3 - Preliminary determination; notice.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....3 Section 223.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CONTENTS OF PERMITS; REVISION, REVOCATION OR LIMITATION OF OCEAN DUMPING PERMITS UNDER SECTION 104(d) OF THE ACT Procedures for Revision, Revocation or Limitation of Ocean Dumping Permits Under Section 104(d...

  15. 40 CFR 223.3 - Preliminary determination; notice.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....3 Section 223.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CONTENTS OF PERMITS; REVISION, REVOCATION OR LIMITATION OF OCEAN DUMPING PERMITS UNDER SECTION 104(d) OF THE ACT Procedures for Revision, Revocation or Limitation of Ocean Dumping Permits Under Section 104(d...

  16. 40 CFR 223.3 - Preliminary determination; notice.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ....3 Section 223.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CONTENTS OF PERMITS; REVISION, REVOCATION OR LIMITATION OF OCEAN DUMPING PERMITS UNDER SECTION 104(d) OF THE ACT Procedures for Revision, Revocation or Limitation of Ocean Dumping Permits Under Section 104(d...

  17. 40 CFR 227.4 - Criteria for evaluating environmental impact.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... impact. 227.4 Section 227.4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental... impact prohibitions, limits, and conditions for the dumping of materials into ocean waters. If the...

  18. 40 CFR 223.3 - Preliminary determination; notice.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....3 Section 223.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CONTENTS OF PERMITS; REVISION, REVOCATION OR LIMITATION OF OCEAN DUMPING PERMITS UNDER SECTION 104(d) OF THE ACT Procedures for Revision, Revocation or Limitation of Ocean Dumping Permits Under Section 104(d...

  19. 40 CFR 227.5 - Prohibited materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 227.5 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental Impact § 227.5 Prohibited materials. The ocean dumping of the following materials will not be approved by EPA or the Corps...

  20. 40 CFR 227.17 - Basis for determination.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Section 227.17 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Impact of the Proposed Dumping on Esthetic, Recreational and Economic Values § 227.17 Basis for determination. (a) The impact of...

  1. 40 CFR 227.17 - Basis for determination.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Section 227.17 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Impact of the Proposed Dumping on Esthetic, Recreational and Economic Values § 227.17 Basis for determination. (a) The impact of...

  2. 40 CFR 227.4 - Criteria for evaluating environmental impact.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... impact. 227.4 Section 227.4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental... impact prohibitions, limits, and conditions for the dumping of materials into ocean waters. If the...

  3. 40 CFR 227.4 - Criteria for evaluating environmental impact.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... impact. 227.4 Section 227.4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Environmental... impact prohibitions, limits, and conditions for the dumping of materials into ocean waters. If the...

  4. 40 CFR 227.17 - Basis for determination.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Section 227.17 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Impact of the Proposed Dumping on Esthetic, Recreational and Economic Values § 227.17 Basis for determination. (a) The impact of...

  5. Contamination of water due to major industries and open refuse dumping in the steel city of Orissa--a case study.

    PubMed

    Mishra, P C; Behera, P C; Patel, R K

    2005-04-01

    Contamination of ground water is common in the areas surrounded by industrial refuse dumping sites and the probability of contamination is more where dumping is done in low lying areas and the rate of percolation through the soil is high. In order to assess the ground water pollution by leachate around the refuse dumping site, eighteen wells were selected for study. Few wells are nearer to the dumps, few are far away and others are in between. Also an attempt has been made to evaluate the effect of industrial effluents on the ground and surface water due to Integrated Rourkela Steel Plant and other major industries. From the analytical data of physico-chemical parameters, it is indicated that the river water is contaminated mainly due to the industrial and municipal effluents and the ground water of some of the analyzed areas is contaminated due to municipal and industrial solid waste dumping.

  6. Study of Internal Dump Stability of Dudhichua Open Cast Project, Northern Coalfields Limited, India

    NASA Astrophysics Data System (ADS)

    Sengupta, S.; Roy, I.

    2015-04-01

    Dudhichua Open Cast Project is one of the prestigious projects of Northern Coalfields Limited, India; with total mineable coal reserves of approximately 400 million tonnes and corresponding 1,700 million m3 volume of waste rock i.e. overburden material. Accommodating this waste dump masses in the limited space of the de-coaled portion of the quarry is considered as one of the major challenges to the mine operators. It has been reported that this mine is facing frequent slope failures of waste rock dumps which is of great concern to the mine management in view of unsafe working condition. To tackle the above problem, a detailed investigation was carried out to propose a stable dump profile which will cater to the land economics and safety aspects of the mine. A detailed investigation along with recommendation of optimum design for dragline dump profile along with shovel-dumper-dump profile is presented in this paper.

  7. Mechanochemical symmetric breaking in cell motility of slime mold

    NASA Astrophysics Data System (ADS)

    Guy, Robert; Zhang, Shun; Del Alamo, Juan Carlos

    2016-11-01

    The cytoplasm of the true slime mold Physarum polycephalum exhibits regular rhythmic periodic shuttle streaming though the cell in the direction of motion. The fluid motion is driven by the periodic contraction of an actin-myosin gel that is regulated by a calcium oscillation. When the organism is small (< 100 microns) there is no shuttle streaming, but beyond this size, regular back-and-forth streaming appears and the cell begins to migrate. In this talk we analyze a mechanochemical model of the cell which includes the intracellular fluid, the active contractile cytoskeleton, the adhesion to the substrate, and the dynamics of a chemical oscillator. We use this analysis along with experimental data to identify the instability related to the onset of streaming in order to bring insight into how contraction, flow, and adhesion are coordinated during locomotion.

  8. Deflate decompressor

    DOEpatents

    Hamlet, Jason R [Albuquerque, NM; Robertson, Perry J [Albuquerque, NM; Pierson, Lyndon G [Albuquerque, NM; Olsberg, Ronald R [Albuquerque, NM

    2012-02-28

    A deflate decompressor includes at least one decompressor unit, a memory access controller, a feedback path, and an output buffer unit. The memory access controller is coupled to the decompressor unit via a data path and includes a data buffer to receive the data stream and temporarily buffer a first portion the data stream. The memory access controller transfers fixed length data units of the data stream from the data buffer to the decompressor unit with reference to a memory pointer pointing into the memory buffer. The feedback path couples the decompressor unit to the memory access controller to feed back decrement values to the memory access controller for updating the memory pointer. The decrement values each indicate a number of bits unused by the decompressor unit when decoding the fixed length data units. The output buffer unit buffers a second portion of the data stream after decompression.

  9. Is back-electron transfer process in Betaine-30 coherent?

    NASA Astrophysics Data System (ADS)

    Rafiq, Shahnawaz; Scholes, Gregory D.

    2017-09-01

    The possible role of coherent vibrational motion in ultrafast photo-induced electron transfer remains unclear despite considerable experimental and theoretical advances. We revisited this problem by tracking the back-electron transfer (bET) process in Betaine-30 with broadband pump-probe spectroscopy. Dephasing time constant of certain high-frequency vibrations as a function of solvent shows a trend similar to the ET rates. In the purview of Bixon-Jortner model, high-frequency quantum vibrations bridge the reactant-product energy gap by providing activationless vibronic channels. Such interaction reduces the effective coupling significantly and thereby the coherence effects are eliminated due to energy gap fluctuations, making the back-electron transfer incoherent.

  10. Environmental and economic analyses of waste disposal options for traditional markets in Indonesia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aye, Lu; Widjaya, E.R.

    2006-07-01

    Waste from traditional markets in Indonesia is the second largest stream of municipal solid waste after household waste. It has a higher organic fraction and may have greater potential to be managed on a business scale compared to household wastes. The attributed reason is that in general the wastes generated from traditional markets are more uniform, more concentrated and less hazardous than waste from other sources. This paper presents the results of environmental and economic assessments to compare the options available for traditional market waste disposal in Indonesia. The options compared were composting in labour intensive plants, composting in amore » centralised plant that utilised a simple wheel loader, centralised biogas production and landfill for electricity production. The current open dumping practice was included as the baseline case. A life cycle assessment (LCA) was used for environmental analysis. All options compared have lower environmental impacts than the current practice of open dumping. The biogas production option has the lowest environmental impacts. A cost-benefit analysis, which considered greenhouse gas savings, was used for the economic assessment. It was found that composting at a centralised plant is the most economically feasible option under the present Indonesian conditions. The approach reported in this study could be applied for 'a pre-feasibility first cut comparison' that includes environmental aspects in a decision-making framework for developing countries even though European emission factors were used.« less

  11. 40 CFR 227.20 - Basis for determination.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 227.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Impact of the Proposed... subpart E will be based on the impact of the proposed dumping on specific uses of the ocean rather than on...

  12. Effects of watershed-scale land use change on stream nitrate concentrations

    USGS Publications Warehouse

    Schilling, K.E.; Spooner, J.

    2006-01-01

    The Walnut Creek Watershed Monitoring Project was conducted from 1995 through 2005 to evaluate the response of stream nitrate concentrations to changing land use patterns in paired 5000-ha Iowa watersheds. A large portion of the Walnut Creek watershed is being converted from row crop agriculture to native prairie and savanna by the U.S. Fish and Wildlife Service at the Neal Smith National Wildlife Refuge (NSNWR). Before restoration, land use in both Walnut Creek (treatment) and Squaw Creek (control) watersheds consisted of 70% row crops. Between 1990 and 2005, row crop area decreased 25.4% in Walnut Creek due to prairie restoration but increased 9.2% in Squaw Creek due to Conservation Reserve Program (CRP) grassland conversion back to row crop. Nitrate concentrations ranged between <0.5 to 14 mg L-1 at the Walnut Creek outlet and 2.1 to 15 mg L-1 at the downstream Squaw Creek outlet. Nitrate concentrations decreased 1.2 mg L-1 over 10 yr in the Walnut Creek watershed but increased 1.9 mg L-1 over 10 yr in Squaw Creek. Changes in nitrate were easier to detect and more pronounced in monitored subbasins, decreasing 1.2 to 3.4 mg L-1 in three Walnut Creek subbasins, but increasing up to 8.0 and 11.6 mg L-1 in 10 yr in two Squaw Creek subbasins. Converting row crop lands to grass reduced stream nitrate levels over time in Walnut Creek, but stream nitrate rapidly increased in Squaw Creek when CRP grasslands were converted back to row crop. Study results highlight the close association of stream nitrate to land use change and emphasize that grasslands or other perennial vegetation placed in agricultural settings should be part of a long-term solution to water quality problems. ?? ASA, CSSA, SSSA.

  13. Pump-dump iterative squeezing of vibrational wave packets.

    PubMed

    Chang, Bo Y; Sola, Ignacio R

    2005-12-22

    The free motion of a nonstationary vibrational wave packet in an electronic potential is a source of interesting quantum properties. In this work we propose an iterative scheme that allows continuous stretching and squeezing of a wave packet in the ground or in an excited electronic state, by switching the wave function between both potentials with pi pulses at certain times. Using a simple model of displaced harmonic oscillators and delta pulses, we derive the analytical solution and the conditions for its possible implementation and optimization in different molecules and electronic states. We show that the main constraining parameter is the pulse bandwidth. Although in principle the degree of squeezing (or stretching) is not bounded, the physical resources increase quadratically with the number of iterations, while the achieved squeezing only increases linearly.

  14. Stabilizing photoassociated Cs2 molecules by optimal control

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Xie, Ting; Huang, Yin; Wang, Gao-Ren; Cong, Shu-Lin

    2013-01-01

    We demonstrate theoretically that photoassociated molecules can be stabilized to deeply bound states. This process is achieved by transferring the population from the outer well to the inner well using the optimal control theory, the Cs2 molecule is taken as an example. Numerical calculations show that weakly bound molecules formed in the outer well by a pump pulse can be compressed to the inner well via a vibrational level of the ground electronic state as an intermediary by an additionally optimized laser pulse. The positively chirped pulse can enhance the population of the target state. With a transform-limited dump pulse, nearly all the photoassociated molecules in the inner well of the excited electronic state can be transferred to the deeply vibrational level of the ground electronic state.

  15. Geothermal alteration of Kamchatka rock physical properties: experimental and pore-scale modeling study

    NASA Astrophysics Data System (ADS)

    Shanina, Violetta; Gerke, Kirill; Bichkov, Andrey; Korost, Dmitry

    2013-04-01

    Alternative renewable energy sources research is getting more and more attention due to its importance for future exploitation and low ecological impacts. Geothermal energy is quite abundant and represents a cheap and easily extractable power source for electricity generation or central heating. For these purposes naturally heated geothermal fluids are extracted via drilled wells; after cooling water is usually pumped back to the reservoir to create a circle, or dumped into local streams. In addition to fundamental interest in understanding natural geothermal processes inside the reservoir, in both cases fluids can significantly alter rock properties around the well or stream bed, which is of great practical and ecological importance for the geothermal industry. Detailed knowledge of these transformations is necessary for power plant construction and well design, geophysical modeling and the prediction of geological properties. Under natural conditions such processes occur within geological time frames and are hard to capture. To accelerate geothermal alteration and model deep reservoir high temperature and pressure conditions we use autoclave laboratory experiments. To represent different geothermal conditions, rock samples are autoclaved using a wide range of parameters: temperature (100-450°C), pressure (16-1000 Bars), solution chemistry (from acidic to alkali artificial solutions and natural geothermal fluids sampled in Kamchatka), duration (from weeks to 1 year). Rock samples represent unaltered andesite-dacite tuffs, basalts and andesite collected at the Kamchatka peninsula. Numerous rock properties, e.g., density (bulk and specific), porosity (total and effective), hygroscopicity, P/S wave velocities, geomechanical characteristics (compressive and tensile strength, elastic modulus), etc., were thoroughly analyzed before and after alteration in laboratory autoclave or natural conditions (in situ). To reveal structural changes, some samples were scanned using X-ray microtomography prior to any alteration and after the experiments. 3D images were used to quantify structural changes and to determine permeability values using a pore-scale modeling approach, as laboratory measurements with through flow are known to have a potential to modify the pore structure. Chemical composition and local mineral formations were investigated using a «Spectroscan Max GV» spectrometer and scanning electron microscope imaging. Our study revealed significant relationships between structure modifications, physical properties and alteration conditions. Main results and conclusions include: 1) initial porosity and its connectivity have substantial effect on alteration dynamics, rocks with higher porosity values and connected pore space exhibit more pronounced alterations; 2) under similar experimental conditions (pressure, temperature, duration) pH plays an important role, acidic conditions result in significant new mineral formation; 3) almost all physical properties, including porosity, permeability, and elastic properties, were seriously modified in the modeled geothermal processes within short (from geological point of view) time frames; 4) X-ray microtomography was found useful for mineral phases distribution and the pore-scale modeling approach was found to be a promising technique to numerically obtain rock properties based on 3D scans; 5) we conclude that alteration and change of reservoir rocks should be taken into account for re-injecting well and geothermal power-plant design.

  16. 30 CFR 56.9301 - Dump site restraints.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Dump site restraints. 56.9301 Section 56.9301 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... § 56.9301 Dump site restraints. Berms, bumper blocks, safety hooks, or similar impeding devices shall...

  17. 30 CFR 56.9301 - Dump site restraints.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Dump site restraints. 56.9301 Section 56.9301 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... § 56.9301 Dump site restraints. Berms, bumper blocks, safety hooks, or similar impeding devices shall...

  18. 30 CFR 57.9301 - Dump site restraints.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Dump site restraints. 57.9301 Section 57.9301 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... § 57.9301 Dump site restraints. Berms, bumper blocks, safety hooks, or similar impeding devices shall...

  19. 7 CFR 58.212 - Hopper or dump room.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Hopper or dump room. 58.212 Section 58.212 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....212 Hopper or dump room. A separate room shall be provided for the transfer of bulk dry dairy products...

  20. 40 CFR 227.20 - Basis for determination.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Section 227.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Impact of the Proposed... subpart E will be based on the impact of the proposed dumping on specific uses of the ocean rather than on...

  1. 40 CFR 227.20 - Basis for determination.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Section 227.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Impact of the Proposed... subpart E will be based on the impact of the proposed dumping on specific uses of the ocean rather than on...

  2. 40 CFR 227.20 - Basis for determination.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Section 227.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Impact of the Proposed... subpart E will be based on the impact of the proposed dumping on specific uses of the ocean rather than on...

  3. 40 CFR 227.20 - Basis for determination.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Section 227.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Impact of the Proposed... subpart E will be based on the impact of the proposed dumping on specific uses of the ocean rather than on...

  4. Ultrashort-pulse-train pump and dump excitation of a diatomic molecule

    NASA Astrophysics Data System (ADS)

    de Araujo, Luís E. E.

    2010-09-01

    An excitation scheme is proposed for transferring population between ground-vibrational levels of a molecule. The transfer is accomplished by pumping and dumping population with a pair of coherent ultrashort-pulse trains via a stationary state. By mismatching the teeth of the frequency combs associated with the pulse trains to the vibrational levels, high selectivity in the excitation, along with high transfer efficiency, is predicted. The pump-dump scheme does not suffer from spontaneous emission losses, it is insensitive to the pump-dump-train delay, and it requires only basic pulse shaping.

  5. Ultrashort-pulse-train pump and dump excitation of a diatomic molecule

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Araujo, Luis E. E. de

    An excitation scheme is proposed for transferring population between ground-vibrational levels of a molecule. The transfer is accomplished by pumping and dumping population with a pair of coherent ultrashort-pulse trains via a stationary state. By mismatching the teeth of the frequency combs associated with the pulse trains to the vibrational levels, high selectivity in the excitation, along with high transfer efficiency, is predicted. The pump-dump scheme does not suffer from spontaneous emission losses, it is insensitive to the pump-dump-train delay, and it requires only basic pulse shaping.

  6. Monitoring the growth or decline of vegetation on mine dumps

    NASA Technical Reports Server (NTRS)

    Gilbertson, B. P. (Principal Investigator)

    1975-01-01

    The author has identified the following signficant results. It was established that particular mine dumps throughout the entire test area can be detected and identified. It was also established that patterns of vegetative growth on the mine dumps can be recognized from a simple visual analysis of photographic images. Because vegetation tends to occur in patches on many mine dumps, it is unsatisfactory to classify complete dumps into categories of percentage vegetative cover. A more desirable approach is to classify the patches of vegetation themselves. The coarse resolution of conventional densitometers restricts the accuracy of this procedure, and consequently a direct analysis of ERTS CCT's is preferred. A set of computer programs was written to perform the data reading and manipulating functions required for basic CCT analysis.

  7. Chevron beam dump for ITER edge Thomson scattering system.

    PubMed

    Yatsuka, E; Hatae, T; Vayakis, G; Bassan, M; Itami, K

    2013-10-01

    This paper contains the design of the beam dump for the ITER edge Thomson scattering system and mainly concerns its lifetime under the harsh thermal and electromagnetic loads as well as tight space allocation. The lifetime was estimated from the multi-pulse laser-induced damage threshold. In order to extend its lifetime, the structure of the beam dump was optimized. A number of bent sheets aligned parallel in the beam dump form a shape called a chevron which enables it to avoid the concentration of the incident laser pulse energy. The chevron beam dump is expected to withstand thermal loads due to nuclear heating, radiation from the plasma, and numerous incident laser pulses throughout the entire ITER project with a reasonable margin for the peak factor of the beam profile. Structural analysis was also carried out in case of electromagnetic loads during a disruption. Moreover, detailed issues for more accurate assessments of the beam dump's lifetime are clarified. Variation of the bi-directional reflection distribution function (BRDF) due to erosion by or contamination of neutral particles derived from the plasma is one of the most critical issues that needs to be resolved. In this paper, the BRDF was assumed, and the total amount of stray light and the absorbed laser energy profile on the beam dump were evaluated.

  8. Determination of technological parameters in strip mining by time-of-flight and image processing

    NASA Astrophysics Data System (ADS)

    Elandaloussi, Frank; Mueller, B.; Osten, Wolfgang

    1999-09-01

    The conveying and dumping of earth masses lying over the coal seam in lignite surface mining is done usually by overburden conveyor bridges. The overburden, obtained from connected excavators, is transported over the bridge construction using a conveyor belt system and poured into one front dump and three surface dumps. The shaping of the dump growth is of great importance both to guaranty the stability of the masses dumped to earth stocks as well as the whole construction and to prepare the area for re-cultivation. This article describes three measurement systems: one to determine the impact point of the dumped earth masses, one to determine the shape of the entire mining process and the other a sensor for the loading of the conveyor belt. For the first measurement system, a real-time video system has been designed, set-up and installed that is capable to determine the impact point of all three dumps simultaneously. The second measurement system is a connection of 5 special designed laser distance measuring instruments, that are able to measure the shape of the mining process under unfavorable environmental conditions like dust, high temperature changes, heavy shocks etc. The third sensor is designed for monitoring the transportation of the masses via the conveyor belt system.

  9. Investigation of mine and industry dumps in the FRG in relation to a possible release of natural radioactive elements.

    PubMed

    Schmitz, J

    1985-10-01

    More than 350 dumps of mines and industries in two federal states of the FRG were recorded, measured radiometrically, evaluated, and some of them sampled. Most of the mine dumps belonged to old and smaller residues from lead/zinc and iron ore mining, while the largest depositions contain tailings of modern ore beneficiation or flyash disposal. All mine dumps from uranium exploration in Baden-Württemberg and Bavaria were investigated. The highest doses, up to 100 mSv/a, were found on the piles of the uranium exploration. These depositions, which are supervised and licensed, are followed, in terms of surface dose, by the old uncontrolled mine dumps of silver/cobalt mining with doses up to 20 mSv/a. The numerous porphyry and granite quarries show doses between 1 and 2 mSv/a, as do flyash and slag dumps. The lowest doses were found on the dumps of the hydrothermal Pb/Zn and iron ore deposits, while the slag piles of iron ore processing showed higher thorium values. Assays for Ra-226 and Pb-210 of the materials deposited confirmed the radiometric results. Analyses of seepage waters and gallery waters showed only very few values exceeding the derived drinking water concentrations.

  10. Reconstruction of the inner structure of small scale mining waste dumps by combining GPR and ERTdata.

    NASA Astrophysics Data System (ADS)

    Kniess, Rudolf; Martin, Tina

    2015-04-01

    Two abandoned small waste dumps in the west of the Harz mountains (Germany) were analysed using ground penetrating radar (GPR) and electrical resistivity tomography (ERT). Aim of the project (ROBEHA, funded by the German Federal Ministry of Education and Research (033R105)) is the assessment of the recycling potential of the mining residues taking into account environmental risks of reworking the dump site. One task of the geophysical prospection is the investigation of the inner structure of the mining dump. This is important for the estimation of the approximate volume of potentially reusable mining deposits within the waste dump. The two investigated dump sites are different in age and therefore differ in their structure. The older residues (< 1930) consist of ore processing waste from density separation (stamp mill sand). The younger dump site descends from comprises slag dump waste. The layer of fine grained residues at the first dump site is less than 6 m thick and the slag layer is less than 2 m thick. Both sites are partially overlain by forest or grassland vegetation and characterized by topographical irregularities. Due to the inhomogeneity of the sites we applied electrical resistivity tomography (ERT) and ground penetrating radar (GPR) for detailed investigation. Using ERT we could distinguish various layers within the mining dumps. The resistivities of the dumped material differ from the bedrock resistivities at both sites. The GPR measurements show near surface layer boundaries down to 3 - 4 m. In consecutive campaigns 100 MHz and 200 MHz antennas were used. The GPR results (layer boundaries) were included into the ERT inversion algorithm to enable more precise and stable resistivity models. This needs some special preprocessing steps. The 3D-Position of every electrode from ERT measurement and the GPR antenna position on the surface require an accuracy of less than 1cm. At some points, the layer boundaries and radar wave velocities can be calibrated with borehole stratigraphic data from a mineralogical drilling campaign. This is important for a precise time-depth conversion of reflectors from GPR measurement. This reflectors were taken from radargram and have been adopted as resistivity boundary in the start model of the geoelectric inversion algorithm.

  11. Sustainable Strategies for the Dynamic Equilibrium of the Urban Stream, Cheonggyecheon

    NASA Astrophysics Data System (ADS)

    Seo, D.; Kwon, Y.

    2018-04-01

    Cheonggyecheon, which had been transformed into a 14-lane urban highway and a large underground sewer system, was finally converted back to an urban stream again. Its transformation has been praised as a successful example of urban downtown regeneration and beautification. It is, however, obvious that there have not been prudent ecological considerations since the project’s principal goals were to provide public recreational use and achieve maximum flood control capacity via the use of embankments. For a healthier and sustainable stream environment, Cheonggyecheon should be ecologically re-restored again, based on a dynamic equilibrium model. It must primarily establish a corridor of vegetation, an aquatic transitional zone, and install constructed wetlands nearby which support the water source. The upper streams of Cheonggyecheon should be further restored and supply natural waters. Furthermore, there ultimately needs to be de-channelization for hydrological sustainability. This would vary from merely increasing the sinuosity to thoroughly reconstruct a naturalized stream. Complete dynamic equilibrium of Cheonggyecheon can be accomplished through more fundamental sustainable strategies.

  12. THE POSSIBLE ROLE OF CORONAL STREAMERS AS MAGNETICALLY CLOSED STRUCTURES IN SHOCK-INDUCED ENERGETIC ELECTRONS AND METRIC TYPE II RADIO BURSTS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kong, Xiangliang; Chen, Yao; Feng, Shiwei

    2015-01-10

    Two solar type II radio bursts, separated by ∼24 hr in time, are examined together. Both events are associated with coronal mass ejections (CMEs) erupting from the same active region (NOAA 11176) beneath a well-observed helmet streamer. We find that the type II emissions in both events ended once the CME/shock fronts passed the white-light streamer tip, which is presumably the magnetic cusp of the streamer. This leads us to conjecture that the closed magnetic arcades of the streamer may play a role in electron acceleration and type II excitation at coronal shocks. To examine such a conjecture, we conduct a test-particle simulationmore » for electron dynamics within a large-scale partially closed streamer magnetic configuration swept by a coronal shock. We find that the closed field lines play the role of an electron trap via which the electrons are sent back to the shock front multiple times and therefore accelerated to high energies by the shock. Electrons with an initial energy of 300 eV can be accelerated to tens of keV concentrating at the loop apex close to the shock front with a counter-streaming distribution at most locations. These electrons are energetic enough to excite Langmuir waves and radio bursts. Considering the fact that most solar eruptions originate from closed field regions, we suggest that the scenario may be important for the generation of more metric type IIs. This study also provides an explanation of the general ending frequencies of metric type IIs at or above 20-30 MHz and the disconnection issue between metric and interplanetary type IIs.« less

  13. Using Machine Learning to Enable Big Data Analysis within Human Review Time Budgets

    NASA Astrophysics Data System (ADS)

    Bue, B.; Rebbapragada, U.; Wagstaff, K.; Thompson, D. R.

    2014-12-01

    The quantity of astronomical observations collected by today's instruments far exceeds the capability of manual inspection by domain experts. Scientists often have a fixed time budget of a few hours spend to perform the monotonous task of scanning through a live stream or data dump of candidates that must be prioritized for follow-up analysis. Today's and next generation astronomical instruments produce millions of candidate detection per day, and necessitate the use of automated classifiers that serve as "data triage" in order to filter out spurious signals. Automated data triage enables increased science return by prioritizing interesting or anomalous observations for follow-up inspection, while also expediting analysis by filtering out noisy or redundant observations. We describe three specific astronomical investigations that are currently benefiting from data triage techniques in their respective processing pipelines.

  14. Tracking and data relay satellite system (TDRSS) - A worldwide view from space

    NASA Technical Reports Server (NTRS)

    Macoughtry, W. O.; Harris, D. W.

    1983-01-01

    The development, performance levels, and operational use of the TDRSS satellite system are outlined. The TDRSS spacecraft were conceived in the mid-1960s by NASA as a means of using GEO-positioned satellites to eliminate existing ground stations. The main ground terminal becomes Goddard Space Flight Center, through which users other than the Shuttle can also gain access. The TDRSS functions as a relay vehicle, with very little on-board processing except for status reports inserted into the data stream. Use of the TDRSS system by nonNASA agencies currently costs $110/min for forwards, return, and tracking, $24/min for forward service alone, and $8/min for return service only. The spacecraft can store data on board and dump it to the ground station during the limited hours of operation.

  15. Method for Location of An External Dump in Surface Mining Using the A-Star Algorithm

    NASA Astrophysics Data System (ADS)

    Zajączkowski, Maciej; Kasztelewicz, Zbigniew; Sikora, Mateusz

    2014-10-01

    The construction of a surface mine always involves the necessity of accessing deposits through the removal of the residual overburden above. In the beginning phase of exploitation, the masses of overburden are located outside the perimeters of the excavation site, on the external dump, until the moment of internal dumping. In the case of lignite surface mines, these dumps can cover a ground surface of several dozen to a few thousand hectares. This results from a high concentration of lignite extraction, counted in millions of Mg per year, and the relatively large depth of its residual deposits. Determining the best place for the location of an external dump requires a detailed analysis of existing options, followed by a choice of the most favorable one. This article, using the case study of an open-cast lignite mine, presents the selection method for an external dump location based on graph theory and the A-star algorithm. This algorithm, based on the spatial distribution of individual intersections on the graph, seeks specified graph states, continually expanding them with additional elementary fields until the required surface area for the external dump - defined by the lowest value of the occupied site - is achieved. To do this, it is necessary to accurately identify the factors affecting the choice of dump location. On such a basis, it is then possible to specify the target function, which reflects the individual costs of dump construction on a given site. This is discussed further in chapter 3. The area of potential dump location has been divided into elementary fields, each represented by a corresponding geometrical locus. Ascribed to this locus, in addition to its geodesic coordinates, are the appropriate attributes reflecting the degree of development of its elementary field. These tasks can be carried out automatically thanks to the integration of the method with the system of geospatial data management for the given area. The collection of loci, together with geodesic coordinates, constitutes the points on the graph used during exploration. This is done using the A-star algorithm, which uses a heuristic function, allowing it to identify the optimal solution; therefore, the collection of elementary fields, which occupy the potential construction area of a dump, characterized by the lowest value representing the cost of occupation and dumping of overburden in the area. The precision of the boundary, generated by the algorithm, is dependent on the established size of the elementary field, and should be refined each time by the designer of the surface mine. This article presents the application of the above method of dump location using the example of "Tomisławice," a lignite surface mine owned by PAK KWB Konin S. A. The method made it possible to identify the most favorable dump location on the northeast side of the initial pit, within 2 kilometers of its surrounding area (discussed further in chapter 3). This method is universal in nature and, after certain modifications, can be implemented for other surface mines as well.

  16. Nonlinear magnetic electron tripolar vortices in streaming plasmas.

    PubMed

    Vranjes, J; Marić, G; Shukla, P K

    2000-06-01

    Magnetic electron modes in nonuniform magnetized and unmagnetized streaming plasmas, with characteristic frequencies between the ion and electron plasma frequencies and at spatial scales of the order of the collisionless skin depth, are studied. Two coupled equations, for the perturbed (in the case of magnetized plasma) or self-generated (for the unmagnetized plasma case) magnetic field, and the temperature, are solved in the strongly nonlinear regime and stationary traveling solutions in the form of tripolar vortices are found.

  17. Determining the radon exhalation rate from a gold mine tailings dump by measuring the gamma radiation.

    PubMed

    Ongori, Joash N; Lindsay, Robert; Newman, Richard T; Maleka, Peane P

    2015-02-01

    The mining activities taking place in Gauteng province, South Africa have caused millions of tons of rocks to be taken from underground to be milled and processed to extract gold. The uranium bearing tailings are placed in an estimated 250 dumps covering a total area of about 7000 ha. These tailings dumps contain considerable amounts of radium and have therefore been identified as large sources of radon. The size of these dumps make traditional radon exhalation measurements time consuming and it is difficult to get representative measurements for the whole dump. In this work radon exhalation measurements from the non-operational Kloof mine dump have been performed by measuring the gamma radiation from the dump fairly accurately over an area of more than 1 km(2). Radon exhalation from the mine dump have been inferred from this by laboratory-based and in-situ gamma measurements. Thirty four soil samples were collected at depths of 30 cm and 50 cm. The weighted average activity concentrations in the soil samples were 308 ± 7 Bq kg(-1), 255 ± 5 Bq kg(-1) and 18 ± 1 Bq kg(-1) for (238)U, (40)K and (232)Th, respectively. The MEDUSA (Multi-Element Detector for Underwater Sediment Activity) γ-ray detection system was used for field measurements. The radium concentrations were then used with soil parameters to obtain the radon flux using different approaches such as the IAEA (International Atomic Energy Agency) formula. Another technique the MEDUSA Laboratory Technique (MELT) was developed to map radon exhalation based on (1) recognising that radon exhalation does not affect (40)K and (232)Th activity concentrations and (2) that the ratio of the activity concentration of the field (MEDUSA) to the laboratory (HPGe) for (238)U and (40)K or (238)U and (232)Th will give a measure of the radon exhalation at a particular location in the dump. The average, normalised radon flux was found to be 0.12 ± 0.02 Bq m(-2) s(-1) for the mine dump. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Estimates of water and solute release from a coal waste rock dump in the Elk Valley, British Columbia, Canada.

    PubMed

    Villeneuve, S A; Barbour, S L; Hendry, M J; Carey, S K

    2017-12-01

    Long term (1999 to 2014) flow and water quality data from a rock drain located at the base of a coal waste rock dump constructed in the Elk Valley, British Columbia was used to characterize the release of three solutes (NO 3 - , Cl - and SO 4 2- ) from the dump and obtain whole dump estimates of net percolation (NP). The concentrations of dump derived solutes in the rock drain water were diluted by snowmelt waters from the adjacent natural watershed during the spring freshet and reached a maximum concentration during the winter baseflow period. Historical peak baseflow concentrations of conservative ions (NO 3 - and Cl - ) increased until 2006/07 after which they decreased. This decrease was attributed to completion of the flushing of the first pore volume of water stored within the dump. The baseflow SO 4 2- concentrations increased proportionally with NO 3 - and Cl - to 2007, but then continued to slowly increase as NO 3 - and Cl - concentrations decreased. This was attributed to ongoing production of SO 4 2- due to oxidation of sulfide minerals within the dump. Based on partitioning of the annual volume of water discharged from the rock drain to waste rock effluent (NP) and water entering the rock drain laterally from the natural watershed, the mean NP values were estimated to be 446±50mm/a (area normalized net percolation/year) for the dump and 172±71mm/a for the natural watershed. The difference was attributed to greater rates of recharge in the dump from summer precipitation compared to the natural watershed where rainfall interception and enhanced evapotranspiration will increase water losses. These estimates included water moving through subsurface pathways. However, given the limitations in quantifying these flows the estimated NP rates for both the natural watershed and the waste rock dump are considered to be low, and could be much higher (e.g. ~450mm/a and ~800mm/a). Copyright © 2017 Elsevier B.V. All rights reserved.

  19. The Influence of Plasma Effects of Pair Beams on the Intergalactic Cascade Emission of Blazars

    NASA Astrophysics Data System (ADS)

    Menzler, Ulf; Schlickeiser, Reinhard

    2014-03-01

    The attenuation of TeV γ-rays from distant blazars by the extragalactic background light (EBL) produces relativistic electron-positron pair beams. It has been shown by Broderick et. al. (2012) and Schlickeiser et. al (2012) that a pair beam traversing the intergalactic medium is unstable to linear two-stream instabilities of both electrostatic and electromagnetic nature. While for strong blazars all free pair energy is dissipated in heating the intergalactic medium and a potential electromagnetic cascade via inverse-Compton scattering with the cosmic microwave background is suppressed, we investigate the case of weak blazars where the back reaction of generated electrostatic turbulence leads to a plateauing of the electron energy spectrum. In the ultra-relativistic Thomson limit we analytically calculate the inverse-Compton spectral energy distribution for both an unplateaued and a plateaued beam scenario, showing a peak reduction factor of Rpeak ≈ 0.345. This is consistent with the FERMI non-measurements of a GeV excess in the spectrum of EBL attenuated TeV blazars. Claims on the lower bound of the intergalactic magnetic field strengths, made by several authors neglecting plasma effects, are thus put into question.

  20. Nonlinear, relativistic Langmuir waves in astrophysical magnetospheres

    NASA Technical Reports Server (NTRS)

    Chian, Abraham C.-L.

    1987-01-01

    Large amplitude, electrostatic plasma waves are relevant to physical processes occurring in the astrophysical magnetospheres wherein charged particles are accelerated to relativistic energies by strong waves emitted by pulsars, quasars, or radio galaxies. The nonlinear, relativistic theory of traveling Langmuir waves in a cold plasma is reviewed. The cases of streaming electron plasma, electronic plasma, and two-streams are discussed.

  1. Effect of electron thermal anisotropy on the kinetic cross-field streaming instability

    NASA Technical Reports Server (NTRS)

    Tsai, S. T.; Tanaka, M.; Gaffey, J. D., Jr.; Wu, C. S.; Da Jornada, E. H.; Ziebell, L. F.

    1984-01-01

    The investigation of the kinetic cross-field streaming instability, motivated by the research of collisionless shock waves and previously studied by Wu et al. (1983), is discussed more fully. Since in the ramp region of a quasi-perpendicular shock electrons can be preferentially heated in the direction transverse to the ambient magnetic field, it is both desirable and necessary to include the effect of the thermal anisotropy on the instability associated with a shock. It is found that Te-perpendicular greater than Te-parallel can significantly enhance the peak growth rate of the cross-field streaming instability when the electron beta is sufficiently high. Furthermore, the present analysis also improves the analytical and numerical solutions previously obtained.

  2. 19 CFR 159.58 - Dumping and countervailing duties; action by port director.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 2 2013-04-01 2013-04-01 false Dumping and countervailing duties; action by port director. 159.58 Section 159.58 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND... Dumping and countervailing duties; action by port director. (a) Antidumping matters. Upon receipt of...

  3. 19 CFR 159.58 - Dumping and countervailing duties; action by port director.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Dumping and countervailing duties; action by port director. 159.58 Section 159.58 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND... Dumping and countervailing duties; action by port director. (a) Antidumping matters. Upon receipt of...

  4. 19 CFR 159.58 - Dumping and countervailing duties; action by port director.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 2 2012-04-01 2012-04-01 false Dumping and countervailing duties; action by port director. 159.58 Section 159.58 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND... Dumping and countervailing duties; action by port director. (a) Antidumping matters. Upon receipt of...

  5. 19 CFR 159.58 - Dumping and countervailing duties; action by port director.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Dumping and countervailing duties; action by port director. 159.58 Section 159.58 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND... Dumping and countervailing duties; action by port director. (a) Antidumping matters. Upon receipt of...

  6. 19 CFR 159.58 - Dumping and countervailing duties; action by port director.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 2 2014-04-01 2014-04-01 false Dumping and countervailing duties; action by port director. 159.58 Section 159.58 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND... Dumping and countervailing duties; action by port director. (a) Antidumping matters. Upon receipt of...

  7. 77 FR 31423 - Qualification of Drivers; Application for Exemptions; National Association of the Deaf

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-25

    ... dump trucks and tractor trailer trucks. He would like to drive tractor trailer trucks in interstate... CDL and drive heavy equipment such as a dump truck, or rig truck with a trailer, if granted an... intrastate commerce. This includes experience driving heavy equipment, dump trucks and public works trucks...

  8. 27 CFR 19.343 - Use of spirits, wines, and alcoholic flavoring materials.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Use of spirits, wines, and alcoholic flavoring materials. A proprietor must prepare a dump/batch... ingredients used in the manufacture of a distilled spirits product according to the following rules. (a) Dump record. A proprietor must prepare a dump record when spirits, wines, or alcoholic flavoring materials are...

  9. 40 CFR 220.1 - Purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING GENERAL § 220.1 Purpose... material for the purpose of dumping it in ocean waters pursuant to section 103 of the Act. Except as may be... shall transport from the United States any material for the purpose of dumping it into ocean waters; (2...

  10. 40 CFR 220.1 - Purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING GENERAL § 220.1 Purpose... material for the purpose of dumping it in ocean waters pursuant to section 103 of the Act. Except as may be... shall transport from the United States any material for the purpose of dumping it into ocean waters; (2...

  11. 40 CFR 220.1 - Purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING GENERAL § 220.1 Purpose... material for the purpose of dumping it in ocean waters pursuant to section 103 of the Act. Except as may be... shall transport from the United States any material for the purpose of dumping it into ocean waters; (2...

  12. 19 CFR 159.61 - General.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false General. 159.61 Section 159.61 Customs Duties U.S...) LIQUIDATION OF DUTIES Continued Dumping and Subsidy Offset § 159.61 General. (a) Continued dumping and subsidy... U.S.C. 1675c), known as the Continued Dumping and Subsidy Offset Act of 2000, assessed duties...

  13. 19 CFR 159.61 - General.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false General. 159.61 Section 159.61 Customs Duties U.S...) LIQUIDATION OF DUTIES Continued Dumping and Subsidy Offset § 159.61 General. (a) Continued dumping and subsidy... U.S.C. 1675c), known as the Continued Dumping and Subsidy Offset Act of 2000, assessed duties...

  14. [Inactive dumps in Santa Catarina's carboniferous area: analysis of risks to the public health and the environment].

    PubMed

    Possamai, Fernando Pagani; Viana, Ednilson; Schulz, Harry Edmar; de Costa, Marcel Madeira; Casagrande, Everson

    2007-01-01

    The existence of inactive dumps considerably increases the so-called "environmental liability"; so much so that the final destination of urban solid residues takes a prominent place on the list of environmental issues of societies(1). In the state of Santa Catarina, it can be said that, currently, the real conditions of the "final destination deposits", or simply the inactive dumps, is officially unknown. This is maybe most evident in the carboniferous area of the state that already suffers from the environmental impact of coal mining. This study attempts to make a survey of the inactive dumps in the carboniferous area of Santa Catarina, analysing the risks they represent to public health and to the environment. The results gathered show that, of the eleven municipal districts in the carboniferous area, nine have inactive dumps. In these nine districts, there are eleven inactive dumps that, according to the this evaluation, represent a large risk to public health and the environment when the parameters analysed are taken into acount.

  15. Assessment of heavy metal contamination in soil due to leachate migration from an open dumping site

    NASA Astrophysics Data System (ADS)

    Kanmani, S.; Gandhimathi, R.

    2013-03-01

    The concentration of heavy metals was studied in the soil samples collected around the municipal solid waste (MSW) open dumpsite, Ariyamangalam, Tiruchirappalli, Tamilnadu to understand the heavy metal contamination due to leachate migration from an open dumping site. The dump site receives approximately 400-470 tonnes of municipal solid waste. Solid waste characterization was carried out for the fresh and old municipal solid waste to know the basic composition of solid waste which is dumped in the dumping site. The heavy metal concentration in the municipal solid waste fine fraction and soil samples were analyzed. The heavy metal concentration in the collected soil sample was found in the following order: Mn > Pb > Cu > Cd. The presence of heavy metals in soil sample indicates that there is appreciable contamination of the soil by leachate migration from an open dumping site. However, these pollutants species will continuously migrated and attenuated through the soil strata and after certain period of time they might contaminate the groundwater system if there is no action to be taken to prevent this phenomenon.

  16. Beam Measurement of 11.424 GHz X-Band Linac for Compton Scattering X-ray Source

    NASA Astrophysics Data System (ADS)

    Natsui, Takuya; Mori, Azusa; Masuda, Hirotoshi; Uesaka, Mitsuru; Sakamoto, Fumito

    2010-11-01

    An inverse Compton scattering X-ray source for medical applications, consisting of an X-band (11.424 GHz) linac and Q-switched Nd:YAG laser, is currently being developed at the University of Tokyo. This system uses an X-band 3.5-cell thermionic cathode RF gun for electron beam generation. We can obtain a multi-bunch electron beam with this gun. The beam is accelerated to 30 MeV by a traveling-wave accelerating tube. So far, we have verified stable beam generation (around 2.3 MeV) by using the newly designed RF gun and we have succeeded in beam transportation to a beam dump.

  17. Continuous Wheel Momentum Dumping Using Magnetic Torquers and Thrusters

    NASA Astrophysics Data System (ADS)

    Oh, Hwa-Suk; Choi, Wan-Sik; Eun, Jong-Won

    1996-12-01

    Two momentum management schemes using magnetic torquers and thrusters are sug-gested. The stability of the momentum dumping logic is proved at a general attitude equilibrium. Both momentum dumping control laws are implemented with Pulse-Width- Pulse-Frequency Modulated on-off control, and shown working equally well with the original continuous and variable strength control law. Thrusters are assummed to be asymmetrically configured as a contingency case. Each thruster is fired following separated control laws rather than paired thrusting. Null torque thrusting control is added on the thrust control calculated from the momentum control law for the gener-ation of positive thrusting force. Both magnetic and thrusting control laws guarantee the momentum dumping, however, the wheel inner loop control is needed for the "wheel speed" dumping, The control laws are simulated on the KOrea Multi-Purpose SATellite (KOMPSAT) model.

  18. A back-pack shocker for collecting lamprey ammocoetes

    USGS Publications Warehouse

    Braem, Robert A.; Ebel, Wesley J.

    1961-01-01

    IN 1958, THE BUREAU OF COMMERCIAL FISHERIES began to use specific larvicides for sea lamprey control in streams tributary to the Great Lakes. The successful application of larvicides required treatment of all areas of the streams infested by sea lamprey ammocoetes. Intensive surveys were needed to determine distribution of the larvae. The use of electrical methods to determinelarval distribution has been described (Stauffer and Hansen 1958). A light portable shocker was needed for these surveys because of the difficulty of access to some of the watersheds tributary to Lake Superior.

  19. Geophysical exploration of historical mine dumps for the estimation of valuable residuals

    NASA Astrophysics Data System (ADS)

    Martin, Tina; Knieß, Rudolf; Noell, Ursula; Hupfer, Sarah; Kuhn, Kerstin; Günther, Thomas

    2015-04-01

    Within the project ROBEHA, funded by the German Federal Ministry of Education and Research (033R105) the economic potential of different abandoned dump sites for mine waste in the Harz Mountains was investigated. Two different mining dumps were geophysically and mineralogically analysed in order to characterize the mine dump structure and to estimate the volume of the potential recycling material. The geophysical methods comprised geoelectrics, radar, and spectral induced polarization (SIP). One about 100-year old mining dump containing residues from density separated Ag- and Sb-rich Pb (Zn)-gangue ores was investigated in detail. Like most small-scale mining waste disposal sites this investigated dump is very heterogeneously structured. Therefore, 27 geoelectrical profiles, more than 50 radar profiles, and several SIP profiles were measured and analysed. The results from the radar measurements, registered with the GSSI system and a shielded 200 MHz antenna, show the near surface boundary layer (down to 3-4 m beneath surface) of the waste residuals. These results can be used as pre-information for the inversion process of the geoelectrical data. The geoelectrical results reveal the mineral residues as layers with higher resistivities (> 300 Ohm*m) than the surrounding material. The SIP method found low phase signals (< 0.5°) for the residues. To estimate the volume of the potentially reusable material we analysed each geoelectrical profile and interpolated between the single profiles using the BERT algorithm. Taking into account the wooded areas of the mine dump and other parameters we get a first estimate for the volume of the residues but the economical viability and the environmental impact of the reworking of the dump still needs to be evaluated in detail. The results of the second mine dump, an abandoned Cu and Zn-rich slag heap, show that the slag residues are characterized by higher resistivities and higher phases. A localization of the slag residues which are covered by organic material could be realized applying these geophysical methods.

  20. Fast superconducting magnetic field switch

    DOEpatents

    Goren, Yehuda; Mahale, Narayan K.

    1996-01-01

    The superconducting magnetic switch or fast kicker magnet is employed with electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater that the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles.

  1. Fast superconducting magnetic field switch

    DOEpatents

    Goren, Y.; Mahale, N.K.

    1996-08-06

    The superconducting magnetic switch or fast kicker magnet is employed with electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater that the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles. 6 figs.

  2. System dynamic modeling on construction waste management in Shenzhen, China.

    PubMed

    Tam, Vivian W Y; Li, Jingru; Cai, Hong

    2014-05-01

    This article examines the complexity of construction waste management in Shenzhen, Mainland China. In-depth analysis of waste generation, transportation, recycling, landfill and illegal dumping of various inherent management phases is explored. A system dynamics modeling using Stella model is developed. Effects of landfill charges and also penalties from illegal dumping are also simulated. The results show that the implementation of comprehensive policy on both landfill charges and illegal dumping can effectively control the illegal dumping behavior, and achieve comprehensive construction waste minimization. This article provides important recommendations for effective policy implementation and explores new perspectives for Shenzhen policy makers.

  3. Challenges and Plans for Injection and Beam Dump

    NASA Astrophysics Data System (ADS)

    Barnes, M.; Goddard, B.; Mertens, V.; Uythoven, J.

    The injection and beam dumping systems of the LHC will need to be upgraded to comply with the requirements of operation with the HL-LHC beams. The elements of the injection system concerned are the fixed and movable absorbers which protect the LHC in case of an injection kicker error and the injection kickers themselves. The beam dumping system elements under study are the absorbers which protect the aperture in case of an asynchronous beam dump and the beam absorber block. The operational limits of these elements and the new developments in the context of the HL-LHC project are described.

  4. Audio Watermark Embedding Technique Applying Auditory Stream Segregation: "G-encoder Mark" Able to Be Extracted by Mobile Phone

    NASA Astrophysics Data System (ADS)

    Modegi, Toshio

    We are developing audio watermarking techniques which enable extraction of embedded data by cell phones. For that we have to embed data onto frequency ranges, where our auditory response is prominent, therefore data embedding will cause much auditory noises. Previously we have proposed applying a two-channel stereo play-back feature, where noises generated by a data embedded left-channel signal will be reduced by the other right-channel signal. However, this proposal has practical problems of restricting extracting terminal location. In this paper, we propose synthesizing the noise reducing right-channel signal with the left-signal and reduces noises completely by generating an auditory stream segregation phenomenon to users. This newly proposed makes the noise reducing right-channel signal unnecessary and supports monaural play-back operations. Moreover, we propose a wide-band embedding method causing dual auditory stream segregation phenomena, which enables data embedding on whole public phone frequency ranges and stable extractions with 3-G mobile phones. From these proposals, extraction precisions become higher than those by the previously proposed method whereas the quality damages of embedded signals become smaller. In this paper we present an abstract of our newly proposed method and experimental results comparing with those by the previously proposed method.

  5. PATHOPHYSIOLOGY, DIAGNOSIS AND TREATMENTOF DUMPING SYNDROME AND ITS RELATION TO BARIATRIC SURGERY.

    PubMed

    Chaves, Yasmin da Silva; Destefani, Afrânio Côgo

    The dumping syndrome is frequent in bariatric surgery. It is probably the most common syndrome following partial or complete gastrectomy. Its prevalence in partial gastrectomy can reach up to 50%, thus it can be a significant complication arising from some types of bariatric surgeries. Critical analysis on dumping syndrome, its pathophysiology, diagnosis and treatment. A literature review was performed using the key words: 'dumping syndrome', 'bariatric surgery' and 'rapid dumping syndrome'. Inclusion criteria were: books, original works, case reports and meta-analyzes, and the exclusion criterion was literature review. Concerning the publication time, articles were screened between 1960 and May 2015. The dumping syndrome is complication arising from obesity surgeries, but also can be a result of vagus nerve damage. Diagnosis is done primarily through the use of questionnaires based on scores. The Sigstad score and Arts survey are valid means for assessing the dumping syndrome. Initial therapy consists in the adoption of dietary measures, short acting drugs administration. A síndrome de dumping é frequente após operações bariátricas. É, provavelmente, a mais comum das síndromes que sucedem gastrectomias parciais ou completas. Sua prevalência, em gastrectomias parciais pode chegar a até 50%, tornando-se assim complicação significante em alguns tipos de operações bariátricas. Realizar análise crítica sobre a síndrome de dumping em sua fisiopatologia, diagnóstico e tratamento. Foi realizada revisão bibliográfica utilizando os descritores: 'síndrome de dumping', 'cirurgia bariátrica' e 'síndrome do esvaziamento rápido'. Os critérios de inclusão foram: livros, trabalhos originais, relatos de caso e metanálises; excluíram-se as revisões bibliográficas. Quanto ao tempo de publicação, foram selecionados artigos entre 1960 e maio de 2015. A síndrome de dumping é complicação gastrointestinal oriunda de operações para obesidade, mas também pode ocasionar-se como consequência de danos no nervo vago. Seu diagnóstico é realizado primordialmente através da aplicação de questionários baseados em pontuações. O escore de Sigstad e questionário de Arts são meios válidos para avaliação da síndrome de dumping. A terapia inicial consiste na adoção de medidas dietéticas, ou fármacos administráveis de ação curta.

  6. Design of a Paraxial Inverse Compton Scattering Diagnostic for an Intense Relativistic Electron Beam

    DTIC Science & Technology

    2013-06-01

    with a 50 cm focal length plano-convex lens (Fig. 4). Prior to entering the vacuum the laser light passes through a Brewster angled window, which...1/γ ~ 25 mrad. Brewster angled windows Beam dump Spectra Physics 5J Nd:YAG Focusing lens Insertable power meter z x y 37.8 cm Figure 4...visible green light is upscattered into the soft X-ray range and diverges from the interception point downstream at an angle θs = 1/γ ~ 25 mrad

  7. Radiological Protection Studies for NGLS XTOD

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xiao, Shanjie; Santana-Leitner, Mario; Rokni, Sayed

    The X-ray transport, optics and diagnostic system (XTOD) starts from the end of bending magnets sending electrons to the main dump and ends at the end wall separating the accelerator tunnel from the user experimental hall (hereafter referred as EH wall), as shown in Figure 1. Figure 1.a shows the general schematic and Figure 1.b shows the initial layout with possible shielding components. This document summarizes the extensive studies on the shielding and collimator system design necessary to meet the radiation protection requirements.

  8. Influence of two-stream relativistic electron beam parameters on the space-charge wave with broad frequency spectrum formation

    NASA Astrophysics Data System (ADS)

    Alexander, LYSENKO; Iurii, VOLK

    2018-03-01

    We developed a cubic non-linear theory describing the dynamics of the multiharmonic space-charge wave (SCW), with harmonics frequencies smaller than the two-stream instability critical frequency, with different relativistic electron beam (REB) parameters. The self-consistent differential equation system for multiharmonic SCW harmonic amplitudes was elaborated in a cubic non-linear approximation. This system considers plural three-wave parametric resonant interactions between wave harmonics and the two-stream instability effect. Different REB parameters such as the input angle with respect to focusing magnetic field, the average relativistic factor value, difference of partial relativistic factors, and plasma frequency of partial beams were investigated regarding their influence on the frequency spectrum width and multiharmonic SCW saturation levels. We suggested ways in which the multiharmonic SCW frequency spectrum widths could be increased in order to use them in multiharmonic two-stream superheterodyne free-electron lasers, with the main purpose of forming a powerful multiharmonic electromagnetic wave.

  9. Assessing the fate of explosives derived nitrate in mine waste rock dumps using the stable isotopes of oxygen and nitrogen.

    PubMed

    Hendry, M Jim; Wassenaar, Leonard I; Barbour, S Lee; Schabert, Marcie S; Birkham, Tyler K; Fedec, Tony; Schmeling, Erin E

    2018-05-29

    Ammonium nitrate (NH 4 NO 3 ) mixed with fuel oil is a common blasting agent used to fragment rock into workable size fractions at mines throughout the world. The decomposition and oxidation of undetonated explosives can result in high NO 3 - concentrations in waters emanating from waste rock dumps. We used the stable isotopic composition of NO 3 - (δ 15 N- and δ 18 O-NO 3 - ) to define and quantify the controls on NO 3 - composition in waste rock dumps by studying water-unsaturated and saturated conditions at nine coal waste rock dumps located in the Elk Valley, British Columbia, Canada. Estimates of the extent of nitrification of NH 4 NO 3 in oxic zones in the dumps, initial NO 3 - concentrations prior to denitrification, and the extent of NO 3 - removal by denitrification in sub-oxic to anoxic zones are provided. δ 15 N data from unsaturated waste rock dumps confirm NO 3 - is derived from blasting. δ 15 N- and δ 18 O-NO 3 - data show extensive denitrification can occur in saturated waste rock and in localized zones of elevated water saturation and low oxygen concentrations in unsaturated waste rock. At the mine dump scale, the extent of denitrification in the unsaturated waste rock was inferred from water samples collected from underlying rock drains. Copyright © 2018. Published by Elsevier B.V.

  10. Chevron beam dump for ITER edge Thomson scattering system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yatsuka, E.; Hatae, T.; Bassan, M.

    This paper contains the design of the beam dump for the ITER edge Thomson scattering system and mainly concerns its lifetime under the harsh thermal and electromagnetic loads as well as tight space allocation. The lifetime was estimated from the multi-pulse laser-induced damage threshold. In order to extend its lifetime, the structure of the beam dump was optimized. A number of bent sheets aligned parallel in the beam dump form a shape called a chevron which enables it to avoid the concentration of the incident laser pulse energy. The chevron beam dump is expected to withstand thermal loads due tomore » nuclear heating, radiation from the plasma, and numerous incident laser pulses throughout the entire ITER project with a reasonable margin for the peak factor of the beam profile. Structural analysis was also carried out in case of electromagnetic loads during a disruption. Moreover, detailed issues for more accurate assessments of the beam dump's lifetime are clarified. Variation of the bi-directional reflection distribution function (BRDF) due to erosion by or contamination of neutral particles derived from the plasma is one of the most critical issues that needs to be resolved. In this paper, the BRDF was assumed, and the total amount of stray light and the absorbed laser energy profile on the beam dump were evaluated.« less

  11. Photoelectron spectroscopy of aqueous solutions: Streaming potentials of NaX (X = Cl, Br, and I) solutions and electron binding energies of liquid water and X{sup −}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kurahashi, Naoya; Horio, Takuya; Suzuki, Toshinori, E-mail: suzuki@kuchem.kyoto-u.ac.jp

    2014-05-07

    The streaming potentials of liquid beams of aqueous NaCl, NaBr, and NaI solutions are measured using soft X-ray, He(I), and laser multiphoton ionization photoelectron spectroscopy. Gaseous molecules are ionized in the vicinity of liquid beams and the photoelectron energy shifts are measured as a function of the distance between the ionization point and the liquid beam. The streaming potentials change their polarity with concentration of electrolytes, from which the singular points of concentration eliminating the streaming potentials are determined. The streaming currents measured in air also vanish at these concentrations. The electron binding energies of liquid water and I{sup −},more » Br{sup −}, and Cl{sup −} anions are revisited and determined more accurately than in previous studies.« less

  12. Architecture of portable electronic medical records system integrated with streaming media.

    PubMed

    Chen, Wei; Shih, Chien-Chou

    2012-02-01

    Due to increasing occurrence of accidents and illness during business trips, travel, or overseas studies, the requirement for portable EMR (Electronic Medical Records) has increased. This study proposes integrating streaming media technology into the EMR system to facilitate referrals, contracted laboratories, and disease notification among hospitals. The current study encoded static and dynamic medical images of patients into a streaming video format and stored them in a Flash Media Server (FMS). Based on the Taiwan Electronic Medical Record Template (TMT) standard, EMR records can be converted into XML documents and used to integrate description fields with embedded streaming videos. This investigation implemented a web-based portable EMR interchanging system using streaming media techniques to expedite exchanging medical image information among hospitals. The proposed architecture of the portable EMR retrieval system not only provides local hospital users the ability to acquire EMR text files from a previous hospital, but also helps access static and dynamic medical images as reference for clinical diagnosis and treatment. The proposed method protects property rights of medical images through information security mechanisms of the Medical Record Interchange Service Center and Health Certificate Authorization to facilitate proper, efficient, and continuous treatment of patients.

  13. 75 FR 26131 - National Oil and Hazardous Substance Pollution Contingency Plan; National Priorities List

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-11

    ... publishing a direct final Notice of Deletion of the Asbestos Dump Superfund Site (Site), located in Long Hill... Deletion of the Asbestos Dump Superfund site (Site), from the National Priorities List (NPL). The NPL... discusses the Asbestos Dump Superfund Site and demonstrates how it meets the deletion criteria. Section V...

  14. 75 FR 44250 - Proposed Administrative Settlement Agreement Under Section 122 of the Comprehensive Environmental...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-28

    ... Dump No. 5 Site located in Jersey City, Hudson County, NJ AGENCY: Environmental Protection Agency... certain response costs incurred by EPA at the Turnpike Dump No. 5 Site (``Site'') located in Jersey City.... ADDRESSES: Comments should reference the Turnpike Dump No. 5 Site, EPA Index No. II-CERCLA-02-2010-2015 and...

  15. 76 FR 13208 - Notice of Lodging of Settlement Agreement Under the Clean Air Act, Comprehensive Environmental...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-10

    ... Disposal Superfund Site in Kansas; 8. The 68th Street Dump Superfund Site in Maryland; 9. The Maryland Sand.... The Reclamation Oil Company Site in Michigan; 16. The Rose Township Dump Superfund Site in Michigan; 17. The Springfield Township Dump Superfund Site in Michigan; 18. The Ventron/Velsicol Superfund Site...

  16. Search for vector mediator of dark matter production in invisible decay mode

    NASA Astrophysics Data System (ADS)

    Banerjee, D.; Burtsev, V. E.; Chumakov, A. G.; Cooke, D.; Crivelli, P.; Depero, E.; Dermenev, A. V.; Donskov, S. V.; Dubinin, F.; Dusaev, R. R.; Emmenegger, S.; Fabich, A.; Frolov, V. N.; Gardikiotis, A.; Gerassimov, S. G.; Gninenko, S. N.; Hösgen, M.; Karneyeu, A. E.; Ketzer, B.; Kirpichnikov, D. V.; Kirsanov, M. M.; Konorov, I. V.; Kovalenko, S. G.; Kramarenko, V. A.; Kravchuk, L. V.; Krasnikov, N. V.; Kuleshov, S. V.; Lyubovitskij, V. E.; Lysan, V.; Matveev, V. A.; Mikhailov, Yu. V.; Peshekhonov, D. V.; Polyakov, V. A.; Radics, B.; Rojas, R.; Rubbia, A.; Samoylenko, V. D.; Tikhomirov, V. O.; Tlisov, D. A.; Toropin, A. N.; Trifonov, A. Yu.; Vasilishin, B. I.; Vasquez Arenas, G.; Ulloa, P.; NA64 Collaboration

    2018-04-01

    A search is performed for a new sub-GeV vector boson (A') mediated production of dark matter (χ ) in the fixed-target experiment, NA64, at the CERN SPS. The A', called dark photon, can be generated in the reaction e-Z →e-Z A' of 100 GeV electrons dumped against an active target followed by its prompt invisible decay A'→χ χ ¯. The experimental signature of this process would be an event with an isolated electron and large missing energy in the detector. From the analysis of the data sample collected in 2016 corresponding to 4.3 ×1010 electrons on target no evidence of such a process has been found. New stringent constraints on the A' mixing strength with photons, 10-5≲ɛ ≲10-2, for the A' mass range mA'≲1 GeV are derived. For models considering scalar and fermionic thermal dark matter interacting with the visible sector through the vector portal the 90% C.L. limits 10-11≲y ≲10-6 on the dark-matter parameter y =ɛ2αD(m/χmA')4 are obtained for the dark coupling constant αD=0.5 and dark-matter masses 0.001 ≲mχ≲0.5 GeV . The lower limits αD≳10-3 for pseudo-Dirac dark matter in the mass region mχ≲0.05 GeV are more stringent than the corresponding bounds from beam dump experiments. The results are obtained by using exact tree level calculations of the A' production cross sections, which turn out to be significantly smaller compared to the one obtained in the Weizsäcker-Williams approximation for the mass region mA'≳0.1 GeV .

  17. Magneto-transport study of top- and back-gated LaAlO{sub 3}/SrTiO{sub 3} heterostructures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, W., E-mail: W.Liu@unige.ch; Gariglio, S.; Fête, A.

    2015-06-01

    We report a detailed analysis of magneto-transport properties of top- and back-gated LaAlO{sub 3}/SrTiO{sub 3} heterostructures. Efficient modulation in magneto-resistance, carrier density, and mobility of the two-dimensional electron liquid present at the interface is achieved by sweeping top and back gate voltages. Analyzing those changes with respect to the carrier density tuning, we observe that the back gate strongly modifies the electron mobility while the top gate mainly varies the carrier density. The evolution of the spin-orbit interaction is also followed as a function of top and back gating.

  18. Natural self-reclamation of soils and landscapes affected by agriculture and mining

    NASA Astrophysics Data System (ADS)

    Alekseenko, Vladimir; Bech, Jaume; Alekseenko, Alexey; Shvydkaya, Natalya; Puzanov, Alexander; Roca, Núria

    2017-04-01

    Processes of possible self-restoration of technogenically disturbed soils are studied in Central and Southern European Russia. Reclamation procedures are mainly not implemented in this vast region, and the natural soil restoration is supposed. Heaps overlaying the former steppe and cropland landscapes are created in the course of rock waste stacking after preparative and cleaning mining works during the underground coal extraction. Approximately 1 500 heaps occupying over 8 000 ha were formed in the area of the Donets Coal Basin. Soils are destroyed under heaps, land subsidence occurs in coal mining areas and acid lakes are usually formed in these ground depressions. Spontaneous combustions happen often and can continue for decades. In order to prevent them, heap surfaces are in some cases levelled and filled with water, forming peculiar ponds. After 70 years of heaps existence and ca. 50 years after their ignition, soil formation is just in the early stages. Heap surface differs a lot in geochemical and mineralogical characteristics from those of surrounding steppe soils that suffered substantial changes at distances up to 1 km. Development of plant communities in areas near coal dumps and heaps is one of the indicators of landscape-geochemical changes. Formation of ruderal phytocenoses with 10-15 % of local flora, as well as invasive and introduced plants occurred under the complex impact of ecological conditions. Communities formed by them are distinguished by the structure simplicity, low species diversity, and plant growth anomalies. Quarries and dumps are formed during underground and open-cast mining of ore deposits. During the last 50 years after abandoning mines in forest areas, the 30 m deep quarries have filled with the creep material less for 0.5 m, and sediments from water streams have added 1-3 cm. Thickness of argillaceous layers does not exceed 1-2 cm at small rock chips of the dumps that measures up to 70 km in length. The dumps are partially covered with woody vegetation. As compared to the zonal vegetation, communities of abandoned mines are characterised by 4-5 times lower biomass, structure simplicity, medium or low species diversity, slow growth and reduced vitality of forest-forming species. With a large volume of stripping works, dump areas amount to the first hectares, and they are almost bare even 50 years later. Soils of vineyards abandoned 25 years ago are different from soils of previously existed forest landscapes by heightened average concentrations of Ba, Cr, Cu, and Mo and decreased levels of Li and Ga. Accumulation is up to 42 t/km2 and takeout is up to 6 t/km 2. Soils of tea plantations are characterised by enriched contents of Mn and Ti (hundreds of t/km 2) and decreased levels of Ba, Li, Pb, Be, Yb, and Ge (up to 54 t/km 2), as compared to soils of forest landscapes. Thus, without implementation of special reclamation measures after deposit mining and agronomic activities, self-restoration does not take place even in 50 years. Estimates allow us to assume that natural reclamation will occur in hundreds of years. Keywords: Technosols, self-restoration, self-combustion, flooding.

  19. Endoluminal Revision (OverStitch (TM) , Apollo Endosurgery) of the Dilated Gastroenterostomy in Patients with Late Dumping Syndrome After Proximal Roux-en-Y Gastric Bypass.

    PubMed

    Stier, Christine; Chiappetta, Sonja

    2016-08-01

    Dumping syndrome is a long-term postoperative complication of Roux-en-Y gastric bypass procedures. Morphologically, dumping syndrome usually correlates with a dilatation of the gastroenterostomy with accelerated pouch emptying. Conservative therapy includes diet changes, complementary pharmacotherapy and, if symptoms persist, surgical revision. Surgical options include endoscopic, endoluminal surgery to constrict the gastrojejunostomy using a novel endoscopic suturing device (OverStitch(TM), Apollo). In our study, we aimed to assess the viability, safety and efficacy of this procedure in patients with late dumping; 14 patients who had developed late dumping syndrome underwent surgery using an endoscopic suturing technique (OverStitch(TM), Apollo). Late dumping was confirmed by Sigstad score and an oral glucose tolerance test (OGTT). Prior to surgery, objective analysis of pouch emptying speed was assessed by gastric scintigraphy. Surgery was performed under general anaesthesia. None of the 14 patients suffered intra- or postoperative complications. No postsurgical increase in inflammation parameters was observed. The postinterventional pain scale (visual analogue scale) showed a mean score of 0.5 (range 0-10). In 13 of the 14 patients, no dumping was observed 1-month postsurgery. The postoperative Sigstad score (3.07 ± 2.06; range 1-9) showed an impressive reduction compared with the preoperative score (12.71 ± 4.18; range 7-24) (p < 0.001). Postoperative upper gastrointestinal gastrografin swallow revealed regular emptying in all the patients. The endoluminal endoscopic suturing technique-applied here for surgical revision of gastroenterostomy following Roux-en-Y gastric bypass-represents a promising, novel therapeutic option in late dumping syndrome involving minimal trauma and offering rapid reconvalescence.

  20. Dump system concepts for the Future Circular Collider

    NASA Astrophysics Data System (ADS)

    Bartmann, W.; Atanasov, M.; Barnes, M. J.; Borburgh, J.; Burkart, F.; Goddard, B.; Kramer, T.; Lechner, A.; Ull, A. Sanz; Schmidt, R.; Stoel, L. S.; Ostojic, R.; Rodziewicz, J.; van Trappen, P.; Barna, D.

    2017-03-01

    The Future Circular Collider (FCC-hh) beam dump system must provide a safe and reliable extraction and dilution of the stored beam onto a dump absorber. Energy deposition studies show that damage limits of presently used absorber materials will already be reached for single bunches at 50 TeV. A fast field rise of the extraction kicker is required in order to sufficiently separate swept single bunches on the extraction protection absorbers in case of an asynchronous beam dump. In line with this demand is the proposal of a highly segmented extraction kicker system which allows for accepting a single kicker switch erratic and thus, significantly reduces the probability of an asynchronous beam dump. Superconducting septa are foreseen to limit the overall system length and power consumption. Two extraction system concepts are presented and evaluated regarding overall system length, energy deposition on absorbers, hardware requirements, radiation issues, and layout flexibility.

  1. Remote sensing and laboratory techniques for monitoring ocean dumping

    NASA Technical Reports Server (NTRS)

    Ohlhorst, C. W.; Johnson, R. W.; Meyer, E. R.

    1977-01-01

    Results of field experiments conducted in the Atlantic Coastal Zone indicate that plumes resulting from ocean dumping of acid waste and sewage sludge have distinguishable spectral characteristics when the radiance of the pollutant is normalized (ratioed to) background ocean water. Acid waste spectra peak between 550-650 nm while sewage sludge spectra have peak values at wavelengths of about 700 nm or greater. Results indicate that identification of acid waste and sewage sludge plumes may be independent of geographical location in the Atlantic Coastal Zone. Radiance ratio curves obtained in the laboratory qualitatively agree with those obtained from field experiments. Results from the July 25, 1977, Galveston Deep Ocean Dump Site experiment show the radiance ratio curve of the biodigested industrial waste to be fairly flat and similar to the radiance ratio curves of sewage sludge line dumps and sewage sludge spot dumps that have been in the water for several hours.

  2. Application of remote sensing to monitoring and studying dispersion in ocean dumping

    NASA Technical Reports Server (NTRS)

    Johnson, R. W.; Ohlhorst, C. W.

    1981-01-01

    Remotely sensed wide area synoptic data provides information on ocean dumping that is not readily available by other means. A qualitative approach has been used to map features, such as river plumes. Results of quantitative analyses have been used to develop maps showing quantitative distributions of one or more water quality parameters, such as suspended solids or chlorophyll a. Joint NASA/NOAA experiments have been conducted at designated dump areas in the U.S. coastal zones to determine the applicability of aircraft remote sensing systems to map plumes resulting from ocean dumping of sewage sludge and industrial wastes. A second objective is related to the evaluation of previously developed quantitative analysis techniques for studying dispersion of materials in these plumes. It was found that plumes resulting from dumping of four waste materials have distinctive spectral characteristics. The development of a technology for use in a routine monitoring system, based on remote sensing techniques, is discussed.

  3. Selected Black-Coal Mine Waste Dumps in the Ostrava-Karviná Region: An Analysis of Their Potential Use

    NASA Astrophysics Data System (ADS)

    Niemiec, Dominik; Duraj, Miloš; Cheng, Xianfeng; Marschalko, Marian; Kubáč, Jan

    2017-12-01

    The paper aims to analyse the options for the use of selected black-coal mine waste dump bodies in the Ostrava-Karviná Region. In the Czech Republic there are approximately 70 mine waste dumps, out of which 50 are located in the Ostrava-Karviná Coal District. The issue is highly topical, particularly in the region, because the dump bodies significantly affect the landscape character of the Ostrava-Karviná Region and pose ecological risks. In such cases, their redevelopment and land reclamation are not easy either from the environmental or economic points of view. It is clear that the redevelopment of such geological environment is difficult, and it is vital to make the right decisions as for what purposes the mine waste dumps should be used. Next, it is important to take into account all the economic and environmental aspects of the locality in question.

  4. 40 CFR 63.495 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... current process operating conditions. (iii) Design analysis based on accepted chemical engineering... quantity are production records, measurement of stream characteristics, and engineering calculations. (5...-end process operations using engineering assessment. Engineering assessment includes, but is not...

  5. 40 CFR 63.495 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... current process operating conditions. (iii) Design analysis based on accepted chemical engineering... quantity are production records, measurement of stream characteristics, and engineering calculations. (5...-end process operations using engineering assessment. Engineering assessment includes, but is not...

  6. 40 CFR 63.495 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... current process operating conditions. (iii) Design analysis based on accepted chemical engineering... quantity are production records, measurement of stream characteristics, and engineering calculations. (5...-end process operations using engineering assessment. Engineering assessment includes, but is not...

  7. 40 CFR 63.495 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... current process operating conditions. (iii) Design analysis based on accepted chemical engineering... quantity are production records, measurement of stream characteristics, and engineering calculations. (5...-end process operations using engineering assessment. Engineering assessment includes, but is not...

  8. An analysis of preferences for hazardous substances free products: manufacturing, use and end of life of mobile phones.

    PubMed

    Kaushal, Rajendra Kumar; Nema, Arvind K

    2012-11-01

    Electronic communication devices such as mobile phones pose significant environmental risks when disposed of after the end of their useful life. Mobile communication devices are one of the fastest growing contributors to the electronic waste (e-waste) stream. Recent legislative pressure and increasing awareness about the environmental risk associated with the hazardous components of the electronic products warrants the manufacturers to reduce or replace the hazardous materials with alternatives. The present study analyses the economic consequences of reducing or replacing these hazardous materials and the possible response of the consumers. A strategic game theory model has been applied in this paper for manufacturer and consumers considering the cost difference between hazardous substances free (HSF) and hazardous substance (HS) mobile. Results suggest that the HSF mobiles can be a preferred choice of the manufacturers as well as consumers if the cost of disposal of HS mobiles can be internalized and a marginal incentive (e.g. 0.9% for a cost difference to 5%, and 5.3% for a cost difference to 10%) is given. The study further highlights the need for realizing the fact that passing on the incentives to the consumers in order to promote schemes for return back to manufacturer at its end of life for effective reuse and recycling gives higher returns.

  9. The SHiP experiment at CERN

    NASA Astrophysics Data System (ADS)

    Bonivento, Walter M.

    2017-07-01

    The discovery of the Higgs boson has fully confirmed the Standard Model of particles and fields. Nevertheless, there are still fundamental phenomena, like the existence of dark matter and the baryon asymmetry of the Universe, deserving an explanation that could come from the discovery of new particles. Searches for new physics with accelerators are performed at the LHC, looking for high massive particles coupled to matter with ordinary strength. A new experiment at CERN meant to search for very weakly coupled particles in the few GeV mass domain has been recently proposed. The existence of such particles, foreseen in different theoretical models beyond the Standard Model, is largely unexplored. A beam dump facility using high intensity 400 GeV protons is a copious source of such unknown particles in the GeV mass range. The beam dump is also a copious source of neutrinos and in particular it is an ideal source of tau neutrinos, the less known particle in the Standard Model. The neutrino detector can also search for dark matter through its scattering off the electrons. We report the physics potential of the SHiP experiment.

  10. Micro-Bunched Beam Production at FAST for Narrow Band THz Generation Using a Slit-Mask

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hyun, J.; Crawford, D.; Edstrom Jr, D.

    We discuss simulations and experiments on creating micro-bunch beams for generating narrow band THz radiation at the Fermilab Accelerator Science and Technology (FAST) facility. The low-energy electron beamline at FAST consists of a photoinjector-based RF gun, two Lband superconducting accelerating cavities, a chicane, and a beam dump. The electron bunches are lengthened with cavity phases set off-crest for better longitudinal separation and then micro-bunched with a slit-mask installed in the chicane. We carried out the experiments with 30 MeV electron beams and detected signals of the micro-bunching using a skew quadrupole magnet in the chicane. In this paper, the detailsmore » of micro-bunch beam production, the detection of micro-bunching and comparison with simulations are described.« less

  11. Analog Delta-Back-Propagation Neural-Network Circuitry

    NASA Technical Reports Server (NTRS)

    Eberhart, Silvio

    1990-01-01

    Changes in synapse weights due to circuit drifts suppressed. Proposed fully parallel analog version of electronic neural-network processor based on delta-back-propagation algorithm. Processor able to "learn" when provided with suitable combinations of inputs and enforced outputs. Includes programmable resistive memory elements (corresponding to synapses), conductances (synapse weights) adjusted during learning. Buffer amplifiers, summing circuits, and sample-and-hold circuits arranged in layers of electronic neurons in accordance with delta-back-propagation algorithm.

  12. Environmental impact of coal ash on tributary streams and nearshore water of Lake Erie. Progress report, June 1, 1975--December 31, 1975. [Cd, Zn, Cu, Cr, Fe, Mn

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wood, K.

    The principal study site is the landfill of the Niagara Mohawk Power Corp., Dunkirk, N.Y. Concentrations of dissolved metals are determined in the waters from the site and aquatic invertebrates from ponds and streams at the site are being identified and analyzed for trace metals. Elevated levels of Fe and Mn occur in the runoff from the site and in the aquatic invertebrates. The metals Cd, Zn, Cu, and Cr are found at low levels (ppB range) in the waters and in variable, generally low concentrations in the biota. Taxonomic study is focused primarily on the Chironomidae (10 general) andmore » Ephemeroptera (6 genera) with detailed studies in progress. The rate of leaching of metals from coal ash is also being studied in the laboratory by two methods. Sediments from Lake Erie at Dunkirk, N.Y., are being assessed for textural classification and composition. Attempts are being made to distinguish between coal wastes and other sediment in the silt and finer size range. The dump site is being evaluated for groundwater, surface water, and geological structure, so that trace element cycling can be evaluated.« less

  13. The market of electrical and electronic equipment waste in Portugal: Analysis of take-back consumers' decisions.

    PubMed

    Botelho, Anabela; Ferreira Dias, Marta; Ferreira, Carla; Pinto, Lígia M Costa

    2016-10-01

    This paper aims to ascertain the efficacy and acceptability of five incentive schemes for the take-back of waste electrical and electronic equipment in Portugal, focusing in consumers' perspectives. It assesses users' perception of these items, evaluating the motivations and interests they have concerning the market of waste electrical and electronic equipment. Results indicate, on one hand, a lack of awareness by consumers about the process of take-back of their equipment. On the other hand, results show that information conditions and socio-demographic factors affect consumers' motivations for returning the electrical and electronic equipment at the end of life. In this context, it can be concluded that, in Portugal, the market for the recovery of waste electrical and electronic equipment is still in its infancy. © The Author(s) 2016.

  14. Geochemistry of arsenic in low sulfide-high carbonate coal waste rock, Elk Valley, British Columbia, Canada.

    PubMed

    Biswas, Ashis; Hendry, M Jim; Essilfie-Dughan, Joseph

    2017-02-01

    This study investigated the geochemistry of arsenic (As) in low sulfide-high carbonate coal waste rock of the Elk Valley, British Columbia, Canada. Its abundance and mineralogical associations in waste rock of different placement periods were determined in addition to its mobilization into porewater and rock-drain effluent. The mean (5.34mg/kg; 95% confidence interval: 4.95-5.73mg/kg) As concentration in the waste rock was typical of sedimentary rock. Electron microprobe and As K-edge X-ray absorption near-edge spectroscopic analyses showed the As is predominantly associated with primary pyrites in both source and freshly blasted waste rock. However, in aged waste rock the As is associated with both primary pyrites and secondary Fe oxyhydroxides. Oxidation of pyrite in waste rock dumps was reflected by the presence of high concentrations of SO 4 2- in porewater and oxidation rims of Fe oxyhydroxides around pyrite grains. Acid released from pyrite oxidation to Fe oxyhydroxides is neutralized by carbonate mineral dissolution that buffers the pH in the waste rock to circumneutral values. Adsorption of As onto secondary Fe oxyhydroxides provides an internal geochemical control on As release during pyrite oxidation and porewater flushing from the dump, resulting in the low As concentrations observed in porewater (median: 9.91μg/L) and rock-drain effluent (median: 0.31μg/L). Secondary Fe oxyhydroxides act as a long-term sink for As under present day hydrologic settings in waste rock dumps in the Elk Valley. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Environmental Impacts Of Zirab Coal Washing Plant, Mazandaran, Iran

    NASA Astrophysics Data System (ADS)

    Moore, F.; Esmaeili, A.

    2009-04-01

    Extraction and beneficiation operations associated with coal mining increase the rate of chemical reaction of waste material to air and water media. Zirab coal washing plant is located on the bank of the Cherat stream in Mazandaran province, Iran. coal Mined from central Alborz coalfield mines is not suitable for use in Iranian Steel Corporation. Hence, coal ash content is reduced by physical and chemical processes in this plant. These processes leave a large quantity of liquid and solid wastes that accumulate in waste dump and tailing dam. sediment and water samples taken from Sheshrudbar and Cherat streams and also from Talar river show high concentration of Cd, Mo and As in water samples of coal washing plant and the associated drainage. Eh-pH diagrams revealed the chemical species of elements in water. The enrichment factor and geoaccumulation index show that Cd, Hg, Mo and V are enriched in bottom sediments of the coal washing plant and decrease with increasing distance from the plant. Sequential extraction analysis Results of three sediment samples of Cherat stream show that silicate bound is the major phase in samples taken before and after the plant, but adjacent to the plant, organic bound is dominant. The high concentration of Cd and Mo in the water soluble phase, is noticeable and may result in high mobility and bioavailability of these elements. Mann-Whitney and Wilcoxon tests on six samples, before and after the coal washing plant support the obtained results. Keywords: Zirab; coal washing plant; Sequential extraction analysis; Mann-whitney; Wilcoxon; Enrichment factor; Geoaccumulation index.

  16. The determination of interplanetary magnetic field polarities around sector boundaries using E greater than 2 keV electrons

    NASA Technical Reports Server (NTRS)

    Kahler, S.; Lin, R. P.

    1994-01-01

    The determination of the polarities of interplanetary magnetic fields (whether the field direction is outward from or inward toward the sun) has been based on a comparison of observed field directions with the nominal Parker spiral angle. These polarities can be mapped back to the solar source field polarities. This technique fails when field directions deviate substantially from the Parker angle or when fields are substantially kinked. We introduce a simple new technique to determine the polarities of interplanetary fields using E greater than 2 keV interplanetary electrons which stream along field lines away from the sun. Those electrons usually show distinct unidirectional pitch-angle anisotropies either parallel or anti-parallel to the field. Since the electron flow direction is known to be outward from the sun, the anisotropies parallel to the field indicate outward-pointing, positive-polarity fields, and those anti-parallel indicate inward-pointing, negative-polarity fields. We use data from the UC Berkeley electron experiment on the International Sun Earth Explorer 3 (ISSE-3) spacecraft to compare the field polarities deduced from the electron data, Pe (outward or inward), with the polarities inferred from field directions, Pd, around two sector boundaries in 1979. We show examples of large (greater than 100 deg) changes in azimuthal field direction Phi over short (less than 1 hr) time scales, some with and some without reversals in Pe. The latter cases indicate that such large directional changes can occur in unipolar structures. On the other hand, we found an example of a change in Pe during which the rotation in Phi was less than 30 deg, indicating polarity changes in nearly unidirectional structures. The field directions are poor guides to the polarities in these cases.

  17. Monte Carlo simulation of the back-diffusion of electrons in nitrogen

    NASA Astrophysics Data System (ADS)

    Radmilović-Radjenović, M.; Nina, A.; Nikitović, Ž.

    2009-01-01

    In this paper, the process of back-diffusion in nitrogen is studied by means of Monte Carlo simulations. In particular we analyze the influence of different aspects of back-diffusion in order to simplify the models of plasma displays, low pressure gas breakdown and detectors of high energy particles. The obtained simulation results show that the escape coefficient depends strongly on the reflection coefficient and the initial energy of electrons. It was also found that the back-diffusion range and number of collisions before returning to the cathode in nitrogen are smaller than those in argon for similar conditions.

  18. 75 FR 44251 - Proposed Administrative Settlement Agreement Under Section 122 of the Comprehensive Environmental...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-28

    ... Dump No. 5 Site Located in Jersey City, Hudson County, NJ AGENCY: Environmental Protection Agency... response costs incurred by EPA at the Turnpike Dump No. 5 Site (``Site'') located in Jersey City, Hudson... reference the Turnpike Dump No. 5 Site, EPA Index No. II-CERCLA-02-2010-2015 and should be sent to the U.S...

  19. Orbiter Water Dump Nozzles Redesign Lessons Learned

    NASA Technical Reports Server (NTRS)

    Rotter, Hank

    2017-01-01

    Hank Rotter, NASA Technical Fellow for Environmental Control and Life Support System, will provide the causes and lessons learned for the two Space Shuttle Orbiter water dump icicles that formed on the side of the Orbiter. He will present the root causes and the criticality of these icicles, along with the redesign of the water dump nozzles and lessons learned during the redesign phase.

  20. Environmental Improvement Of Opencast Mining

    NASA Astrophysics Data System (ADS)

    Prokopenko, S.; Sushko, A.; Filatov, Yu; Kislyakov, M.; Kislyakov, I.

    2017-01-01

    Existing classifications of waste dumps in the quarries are given and their phenomenological nature is clarified. The need to identify the essence of the term "dump" is shown as well as the idea of "dump" as an artificial formation with everted and mixed rocks distanced from the quarry. Essential classification of man-made rock formations in quarries is developed. Characteristic of variations of man-made waste formations in quarries is developed. To reduce harmful effects of open-pit mining, dumps should be substituted with strat-lays - man-made structures relevant to natural stratification of litho-substances. Construction of strat-lays would improve ecological and technological culture of open cast mining.

  1. SPIDER beam dump as diagnostic of the particle beam

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zaupa, M., E-mail: matteo.zaupa@igi.cnr.it; Sartori, E.; Consorzio RFX, Corso Stati Uniti 4, Padova 35127

    The beam power produced by the negative ion source for the production of ion of deuterium extracted from RF plasma is mainly absorbed by the beam dump component which has been designed also for measuring the temperatures on the dumping panels for beam diagnostics. A finite element code has been developed to characterize, by thermo-hydraulic analysis, the sensitivity of the beam dump to the different beam parameters. The results prove the capability of diagnosing the beam divergence and the horizontal misalignment, while the entity of the halo fraction appears hardly detectable without considering the other foreseen diagnostics like tomography andmore » beam emission spectroscopy.« less

  2. Slope Stability Analysis of Waste Dump in Sandstone Open Pit Osielec

    NASA Astrophysics Data System (ADS)

    Adamczyk, Justyna; Cała, Marek; Flisiak, Jerzy; Kolano, Malwina; Kowalski, Michał

    2013-03-01

    This paper presents the slope stability analysis for the current as well as projected (final) geometry of waste dump Sandstone Open Pit "Osielec". For the stability analysis six sections were selected. Then, the final geometry of the waste dump was designed and the stability analysis was conducted. On the basis of the analysis results the opportunities to improve the stability of the object were identified. The next issue addressed in the paper was to determine the proportion of the mixture containing mining and processing wastes, for which the waste dump remains stable. Stability calculations were carried out using Janbu method, which belongs to the limit equilibrium methods.

  3. SPIDER beam dump as diagnostic of the particle beam

    NASA Astrophysics Data System (ADS)

    Zaupa, M.; Dalla Palma, M.; Sartori, E.; Brombin, M.; Pasqualotto, R.

    2016-11-01

    The beam power produced by the negative ion source for the production of ion of deuterium extracted from RF plasma is mainly absorbed by the beam dump component which has been designed also for measuring the temperatures on the dumping panels for beam diagnostics. A finite element code has been developed to characterize, by thermo-hydraulic analysis, the sensitivity of the beam dump to the different beam parameters. The results prove the capability of diagnosing the beam divergence and the horizontal misalignment, while the entity of the halo fraction appears hardly detectable without considering the other foreseen diagnostics like tomography and beam emission spectroscopy.

  4. Shuttle Wastewater Solution Characterization

    NASA Technical Reports Server (NTRS)

    Adam, Niklas; Pham, Chau

    2011-01-01

    During the 31st shuttle mission to the International Space Station, STS-129, there was a clogging event in the shuttle wastewater tank. A routine wastewater dump was performed during the mission and before the dump was completed, degraded flow was observed. In order to complete the wastewater dump, flow had to be rerouted around the dump filter. As a result, a basic chemical and microbial investigation was performed to understand the shuttle wastewater system and perform mitigation tasks to prevent another blockage. Testing continued on the remaining shuttle flights wastewater and wastewater tank cleaning solutions. The results of the analyses and the effect of the mitigation steps are detailed in this paper.

  5. Dark matter search in a Beam-Dump eXperiment (BDX) at Jefferson Lab: an update on PR12-16-001

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Battaglieri, M.

    This document is an update to the proposal PR12-16-001 Dark matter search in a Beam-Dump eXperiment (BDX) at Jefferson Lab submitted to JLab-PAC44 in 2016 reporting progress in addressing questions raised regarding the beam-on backgrounds. The concerns are addressed by adopting a new simulation tool, FLUKA, and planning measurements of muon fluxes from the dump with its existing shielding around the dump. First, we have implemented the detailed BDX experimental geometry into a FLUKA simulation, in consultation with experts from the JLab Radiation Control Group. The FLUKA simulation has been compared directly to our GEANT4 simulations and shown to agreemore » in regions of validity. The FLUKA interaction package, with a tuned set of biasing weights, is naturally able to generate reliable particle distributions with very small probabilities and therefore predict rates at the detector location beyond the planned shielding around the beam dump. Second, we have developed a plan to conduct measurements of the muon ux from the Hall-A dump in its current configuration to validate our simulations.« less

  6. Monitoring and sustainable management of oil polluting wrecks and chemical munitions dump sites in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Hassellöv, Ida-Maja; Tengberg, Anders

    2017-04-01

    The Baltic Sea region contains a dark legacy of about 100 000 tons of dumped chemical warfare agents. As time passes the gun shells corrode and the risks of release of contaminants increase. A major goal of the EU-flagship project Daimon is to support governmental organisations with case-to-case adapted methods for sustainable management of dumped toxic munitions. At the Chalmers University of Technology, a partner of Daimon, a unique ISO 31000 adapted method was developed to provide decision support regarding potentially oilpolluting shipwrecks. The method is called VRAKA and is based on probability calculations. It includes site-specific information as well as expert knowledge. VRAKA is now being adapted to dumped chemical munitions. To estimate corrosion potential of gun shells and ship wrecks along with sediment re-suspension and transport multiparameter instruments are deployed at dump sites. Parameters measured include Currents, Salinity, Temperature, Oxygen, Depth, Waves and Suspended particles. These measurements have revealed how trawling at dump sites seems to have large implications in spreading toxic substances (Arsenic) over larger areas. This presentation will shortly describe the decision support model, the used instrumentation and discuss some of the obtain results.

  7. Mobilization and transport of pollutants in an abandoned dump in tropical conditions

    NASA Astrophysics Data System (ADS)

    Pelinson, Natalia; Shinzato, Marjolly; Wendland, Edson

    2017-04-01

    The valuation and treatment techniques of municipal solid waste (MSW) in developing countries are not sufficiently developed, and therefore, the volume of waste destined for disposal still presents significant amounts. In Brazil, the more common practice of final destination is the deposition on the soil, due to its simple operation and low cost compared to other techniques. One of the most serious negative environmental impacts in the irregular disposal of solid waste is the contamination of soil and groundwater by waste leachates. The final disposal in dumps is forbidden by Brazilian law since 2010, nevertheless, the public administration is not prepared to monitor waste disposal areas and the risk of contamination of water. In this sense, a research has been developed in an abandoned dump installed over an outcrop of the Botucatu Formation, which is part of the Guarani Aquifer System (SAG) and therefore, is an area of high water vulnerability. In this dump, an old gully was used as a final waste disposal area for urban, construction and demolition, medical and industrial waste from 1980 to 1996. Since the end of the deposition, the waste body is kept with inefficient hydraulic control. The water infiltration due to rainfall promotes the mobility of contaminant in the deposit. The present water quality in the dump has been monitored through physical and chemical analysis of samples collected in the unsaturated zone (inside the waste mass using vacuum lysimeters) and in the saturated zone (monitoring wells). The rainfall variation observed in the years 2014 (dry year) and 2015 (wet year) contributed significantly to evaluate the mobilization of pollutants within the dump. The reduction of the water volume that infiltrates the waste mass affected the quality of the leachate collected in the lysimeters. The groundwater collected in monitoring wells outside the dump area presents low turbidity values (<1.50 NTU) in relation to wells located downstream of the dump showed values greater than 10, a similar behavior was observed for the conductivity (>1000 µS.cma-1 in leachate) and chlorides values (>800 mg.L-1). Contaminated water flows through the bottom of the dump. In addition, this research also indicates amendments of surface water downstream of the dump area.

  8. Assessment of nonpoint source chemical loading potential to watersheds containing uranium waste dumps associated with uranium exploration and mining, San Rafael Swell, Utah

    USGS Publications Warehouse

    Freeman, Michael L.; Naftz, David L.; Snyder, Terry; Johnson, Greg

    2008-01-01

    During July and August of 2006, 117 solid-phase samples were collected from abandoned uranium waste dumps, geologic background sites, and adjacent streambeds in the San Rafael Swell, in southeastern Utah. The objective of this sampling program was to assess the nonpoint source chemical loading potential to ephemeral and perennial watersheds from uranium waste dumps on Bureau of Land Management property. Uranium waste dump samples were collected using solid-phase sampling protocols. After collection, solid-phase samples were homogenized and extracted in the laboratory using a field leaching procedure. Filtered (0.45 micron) water samples were obtained from the field leaching procedure and were analyzed for Ag, As, Ba, Be, Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Se, U, V, and Zn at the Inductively Coupled Plasma-Mass Spectrometry Metals Analysis Laboratory at the University of Utah, Salt Lake City, Utah and for Hg at the U.S. Geological Survey National Water Quality Laboratory, Denver, Colorado. For the initial ranking of chemical loading potential of suspect uranium waste dumps, leachate analyses were compared with existing aquatic life and drinking-water-quality standards and the ratio of samples that exceeded standards to the total number of samples was determined for each element having a water-quality standard for aquatic life and drinking-water. Approximately 56 percent (48/85) of the leachate samples extracted from uranium waste dumps had one or more chemical constituents that exceeded aquatic life and drinking-water-quality standards. Most of the uranium waste dump sites with elevated trace-element concentrations in leachates were along Reds Canyon Road between Tomsich Butte and Family Butte. Twelve of the uranium waste dump sites with elevated trace-element concentrations in leachates contained three or more constituents that exceeded drinking-water-quality standards. Eighteen of the uranium waste dump sites had three or more constituents that exceeded trace-element concentrations for aquatic life water-quality standards. The proximity of the uranium waste dumps in the Tomsich Butte area near Muddy Creek, coupled with the elevated concentration of trace elements, increases the offsite impact potential to water resources. Future assessment and remediation priority of these areas may be done by using GIS-based risk-mapping techniques, such as Sensitive Catchment Integrated Mapping and Analysis Project.

  9. Monitoring tectonic uplift and paleoenvironmental reconstruction for marine terraces near Maǧaracik and Samandaǧ, Hatay Province, Turkey.

    PubMed

    Florentin, Jonathan A; Blackwell, Bonnie A B; Tüysüz, Okan; Tarı, Ufuk; Can Genç, Ş; İmren, Caner; Mo, Shirley; Huang, Yiwen E W; Blickstein, Joel I B; Skinner, Anne R; Kim, Maria

    2014-06-01

    Near Hatay, the Antakya-Samandağ-Cyprus Fault (ASCF), East Anatolian and Dead Sea Fault Zones, the large faults that form the edges of the African, Anatolian, Cyprus and Arabian Plates, all produce large earthquakes, which have decimated Hatay repeatedly. Near Samandağ, Hatay, differential vertical displacement on the ASCF has uplifted the southeastern side relative to northwestern side, producing large fault scarps that parallel the Asi (Orontes) River. Tectonic uplift coupled with Quaternary sealevel fluctuations has produced several stacked marine terraces stranded above current sealevel. This study dated 24 mollusc samples from 10 outcrops on six marine terraces near Samandağ electron spin resonance (ESR). Ages were calculated using time-averaged and volumetrically averaged external dose rates, modelled by assuming typical water depths for the individual species and sediment thicknesses estimated from geological criteria. Uplift rates were then calculated for each fault block. At all the Mağaracık terraces, the dates suggest that many shells were likely reworked. On the 30 m terrace at Mağaracık IV (UTM 766588-3999880), Lithophagus burrows with in situ shells cross the unconformity. One such shell dated to 62 ± 6 ka, setting the minimum possible age for the terrace. For all the Mağaracık terraces at ∼30 m above mean sealevel (amsl), the youngest ages for the reworked shells, which averaged 60 ± 3 ka for six separate analyses, sets the maximum possible age for this unit. Thus, the terrace must date to 60-62 ± 3 ka, at the MIS 3/4 boundary when temperatures and sealevels were fluctuating rapidly. Older units dating to MIS 7, 6, and 5 likely were being eroded to supply some fossils found in this terrace. At Mağaracık Dump (UTM 765391-4001048), ∼103 m amsl, Ostrea and other shells were found cemented in growth position to the limestone boulders outcropping there <2.0 m above a wave-eroded notch. If the oysters grew at the same time as the wave-cut notch and the related terrace, the date, 91 ± 13 ka, for the oysters, this fault block has been uplifted at 1.19 ± 0.15 m ky(-1), since MIS 5c. At Samandağ Kurt Stream at 38 m amsl, molluscs were deposited fine sandy gravel, which was likely formed in a large tidal channel. Four molluscs averaged 116 ± 5 ka. If these molluscs have not been reworked, this fault block has uplifted at 0.34 ± 0.05 m ky(-1) since the MIS 5d/5e boundary. The differences in these uplift rates suggests that at least one, and possibly two, hitherto undiscovered faults may separate the Mağaracık Dump site from the other Mağaracık sites and from the Samandağ Kurt Stream site. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Collective effects in the Thomson back-scattering between a laser pulse and a relativistic electron beam

    NASA Astrophysics Data System (ADS)

    Bacci, A.; Maroli, C.; Petrillo, V.; Serafini, L.

    2006-08-01

    Collective effects in the radiation emission via Thomson back-scattering of an intense optical laser pulse by high brightness electron beams are analyzed. The micro-bunching of the electron beam on the scale of the wavelength of the emitted radiation and the consequent free-electron-laser instability may significantly enhance the number of photons emitted. Scaling-laws of the radiation properties, both in the collective and incoherent spontaneous regimes versus laser and electron beam parameters are discussed in the framework of the one-dimensional model.

  11. Effects of the Huguenot Diaspora on the American Revolution

    DTIC Science & Technology

    2016-06-10

    99 Scots from Scotland and other warmer Locales...106 viii The Scots -Irish or Ulster Scots : Huguenots through the Back Door .......................... 111 The Minor Streams...immigrated to the Shenandoah Valley by way of Baltimore, Maryland. Over a couple of generations the family assimilated into the Scots

  12. Electron-beam induced current characterization of back-surface field solar cells using a chopped scanning electron microscope beam

    NASA Technical Reports Server (NTRS)

    Luke, K. L.; Cheng, L.-J.

    1984-01-01

    A chopped electron beam induced current (EBIC) technique for the chacterization of back-surface field (BSF) solar cells is presented. It is shown that the effective recombination velocity of the low-high junction forming the back-surface field of BSF cells, in addition to the diffusion length and the surface recombination velocity of the surface perpendicular to both the p-n and low-high junctions, can be determined from the data provided by a single EBIC scan. The method for doing so is described and illustrated. Certain experimental considerations taken to enhance the quality of the EBIC data are also discussed.

  13. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mazarakis, Michael G.; Kiefer, Mark L.; Leckbee, Joshua J.

    This paper describes our effort to measure the back-streaming ions emitted from the target x-ray convertor and thus estimate the ion contribution to the A-K gap bipolar current flow. Knowing the ion contribution is quite important in order to calculate the expected x-ray dose and compare it with the actual measurements. Our plans were first to measure the total ion current using B-dot monitors, Rogowski coils, and Faraday cups and then to utilize filtered Faraday cups and time of flight techniques to identify and measure the various ionic species. The kinetic energy (velocities) of the ions should help evaluate themore » actual voltage applied at the anode-cathode (A-K) gap. LSP simulations found that the most prominent ions are protons and carbon single plus (C+). For an 8-MV A-K voltage, the estimated proton current back-streaming through an 1 cm in diameter hollow cathode tip was on the average 3 kA and the carbon current 0.7 kA. Since only a small fraction of the ions will make it through the cylindrical aperture, the corresponding total currents were calculated to be respectively 25kA for proton and 7 kA for carbon ions, a quite substantial contribution to the total bipolar beam current. Hence, approximately only 10% of the total back-streaming ionic currents could make it through the hollow cathode tip aperture. Unfortunately the diagnostic cables connecting the Faraday cup and the B-dot monitors to the screen room scopes experienced a large amount of charge pick-up that obliterated our effort to directly measure those relatively small currents. However, we succeeded in measuring those currents indirectly with activation techniques [Contribution of the back-streaming ions to the self-magnetic pinch (SMP) diode Current., M. G. Mazarakis, M. G. Mazarakis, M. E. Cuneo, S. D. Fournier, M. D. Johnston, M. L. Kiefer, J. J. Leckbee, D. S. Nielsen, B.V.Oliver, M. E. Sceiford, S. C. Simpson, T. J. Renk, C. L. Ruiz, T. J. Webb, and D. Ziska. Subitted for publication.]. In the following sections we present some typical cable pick-up results and also our efforts to verify that the observed “current” scope traces were indeed not ion currents but instead cable charge pic-up. Interestingly enough we also discovered that the appearance of those “currents” are in synchronism with the A-K gap impedance variation (decrease) and the MITL sheath current re-trapping. Hence those B-dots or Faraday cups could be utilized as diode behavior diagnostics.« less

  14. Design analysis and simulation study of an efficiency enhanced L-band MILO

    NASA Astrophysics Data System (ADS)

    Dixit, Gargi; Kumar, Arjun; Jain, P. K.

    2017-01-01

    In this article, an experimental L-band compact magnetically insulated transmission line oscillator (MILO) has been simulated using the 3D PIC simulation code "Particle Studio," and an improvement in the device efficiency has been obtained. The detailed interaction and operating mechanism describing the role of sub-assemblies have been explained. The performance of the device was found to be the function of the distance between the end-surface of the cathode and the beam-dump disk. During simulation, a high power microwave of the TM01 mode is generated with the peak RF-power of 6 GW and the power conversion efficiency of 19.2%, at the operating voltage of ˜600 kV and at the current of 52 kA. For better impedance matching or maximum power transfer, four stubs have been placed at the λg/4 distance from the extractor cavity, which results in the stable RF power output. In this work, an improved L-band MILO along with a new type beam-dump disk is selected for performance improvement with typical design parameters and beam parameters. The total peak power of improved MILO is 7 GW, and the maximum power conversion efficiency is 22.4%. This improvement is achieved due to the formation of the virtual cathode at the load side, which helps in modulating the energy of electrons owing to maximum reflection of electrons from the mesh or foil.

  15. Hyporheic exchange and fulvic acid redox reactions in an alpine stream/wetland ecosystem, Colorado front range

    USGS Publications Warehouse

    Miller, Matthew P.; McKnight, Diane M.; Cory, R.M.; Williams, Mark W.; Runkel, Robert L.

    2006-01-01

    The influence of hyporheic zone interactions on the redox state of fulvic acids and other redox active species was investigated in an alpine stream and adjacent wetland, which is a more reducing environment. A tracer injection experiment using bromide (Br-) was conducted in the stream system. Simulations with a transport model showed that rates of exchange between the stream and hyporheic zone were rapid (?? ??? 10-3 s -1). Parallel factor analysis of fluorescence spectra was used to quantify the redox state of dissolved fulvic acids. The rate coefficient for oxidation of reduced fulvic acids (?? = 6.5 ?? 10-3 s -1) in the stream indicates that electron-transfer reactions occur over short time scales. The rate coefficients for decay of ammonium (?? = 1.2 ?? 10-3 s-1) and production of nitrate (?? = -1.0 ?? 10-3 s-1) were opposite in sign but almost equal in magnitude. Our results suggest that fulvic acids are involved in rapid electron-transfer processes in and near the stream channel and may be important in determining ecological energy flow at the catchment scale. ?? 2006 American Chemical Society.

  16. 78 FR 72639 - Non-Malleable Cast Iron Pipe Fittings From the People's Republic of China: Final Results of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-03

    ... dumping margins likely to prevail is indicated in the ``Final Results of Sunset Review'' section of this... likelihood of continuation or recurrence of dumping and the magnitude of the margins likely to prevail if the... dumping margin likely to prevail [FR Doc. 2013-28952 Filed 12-2-13; 8:45 am] BILLING CODE 3510-DS-P ...

  17. 76 FR 34014 - Airworthiness Directives; Bombardier, Inc. Model CL-215-1A10, CL-215-6B11 (CL-215T Variant), and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-10

    ... unsafe condition as: The emergency water dump pulley support bracket assembly, Part Number (P/N) 215-94711-2, has been found cracked or broken on a number of aeroplanes. Failure of the emergency water dump... specified products. The MCAI states: The emergency water dump pulley support bracket assembly, Part Number...

  18. Crew Field Notes: A New Tool for Planetary Surface Exploration

    NASA Technical Reports Server (NTRS)

    Horz, Friedrich; Evans, Cynthia; Eppler, Dean; Gernhardt, Michael; Bluethmann, William; Graf, Jodi; Bleisath, Scott

    2011-01-01

    The Desert Research and Technology Studies (DRATS) field tests of 2010 focused on the simultaneous operation of two rovers, a historical first. The complexity and data volume of two rovers operating simultaneously presented significant operational challenges for the on-site Mission Control Center, including the real time science support function. The latter was split into two "tactical" back rooms, one for each rover, that supported the real time traverse activities; in addition, a "strategic" science team convened overnight to synthesize the day's findings, and to conduct the strategic forward planning of the next day or days as detailed in [1, 2]. Current DRATS simulations and operations differ dramatically from those of Apollo, including the most evolved Apollo 15-17 missions, due to the advent of digital technologies. Modern digital still and video cameras, combined with the capability for real time transmission of large volumes of data, including multiple video streams, offer the prospect for the ground based science support room(s) in Mission Control to witness all crew activities in unprecedented detail and in real time. It was not uncommon during DRATS 2010 that each tactical science back room simultaneously received some 4-6 video streams from cameras mounted on the rover or the crews' backpacks. Some of the rover cameras are controllable PZT (pan, zoom, tilt) devices that can be operated by the crews (during extensive drives) or remotely by the back room (during EVAs). Typically, a dedicated "expert" and professional geologist in the tactical back room(s) controls, monitors and analyses a single video stream and provides the findings to the team, commonly supported by screen-saved images. It seems obvious, that the real time comprehension and synthesis of the verbal descriptions, extensive imagery, and other information (e.g. navigation data; time lines etc) flowing into the science support room(s) constitute a fundamental challenge to future mission operations: how can one analyze, comprehend and synthesize -in real time- the enormous data volume coming to the ground? Real time understanding of all data is needed for constructive interaction with the surface crews, and it becomes critical for the strategic forward planning process.

  19. Assessment of nonpoint source chemical loading potential to watersheds containing uranium waste dumps and human health hazards associated with uranium exploration and mining, Red, White, and Fry Canyons, southeastern Utah, 2007

    USGS Publications Warehouse

    Beisner, Kimberly R.; Marston, Thomas M.; Naftz, David L.; Snyder, Terry; Freeman, Michael L.

    2010-01-01

    During May, June, and July 2007, 58 solid-phase samples were collected from abandoned uranium mine waste dumps, background sites, and adjacent streambeds in Red, White, and Fry Canyons in southeastern Utah. The objectives of this sampling program were to (1) assess the nonpoint-source chemical loading potential to ephemeral and perennial drainage basins from uranium waste dumps and (2) assess potential effects on human health due to recreational activities on and around uranium waste dumps on Bureau of Land Management property. Uranium waste-dump samples were collected using solid-phase sampling protocols. After collection, solid-phase samples were homogenized and extracted in the laboratory using a leaching procedure. Filtered (0.45 micron) water samples were obtained from the field leaching procedure and were analyzed for major and trace elements at the Inductively Coupled Plasma-Mass Spectrometry Metals Analysis Laboratory at the University of Utah. A subset of the solid-phase samples also were digested with strong acids and analyzed for major ions and trace elements at the U.S. Geological Survey Geologic Division Laboratory in Denver, Colorado. For the initial ranking of chemical loading potential for uranium waste dumps, results of leachate analyses were compared with existing aquatic-life and drinking-water-quality standards. To assess potential effects on human health, solid-phase digestion values for uranium were compared to soil screening levels (SSL) computed using the computer model RESRAD 6.5 for a probable concentration of radium. One or more chemical constituents exceeded aquatic life and drinking-water-quality standards in approximately 64 percent (29/45) of the leachate samples extracted from uranium waste dumps. Most of the uranium waste dump sites with elevated trace-element concentrations in leachates were located in Red Canyon. Approximately 69 percent (31/45) of the strong acid digestible soil concentration values were greater than a calculated SSL. Uranium waste dump sites with elevated leachate and total digestible concentrations may need to be further investigated to determine the most appropriate remediation method.

  20. Mercury Handling for the Target System for a Muon Collider

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Graves, Van B; Mcdonald, K; Kirk, H.

    2012-01-01

    The baseline target concept for a Muon Collider or Neutrino Factory is a free-stream mercury jet being impacted by an 8-GeV proton beam. The target is located within a 20-T magnetic field, which captures the generated pions that are conducted to a downstream decay channel. Both the mercury and the proton beam are introduced at slight downward angles to the magnetic axis. A pool of mercury serves as a receiving reservoir for the mercury and a dump for the unexpended proton beam. The impact energy of the remaining beam and jet are substantial, and it is required that splashes andmore » waves be controlled in order to minimize the potential for interference of pion production at the target. Design issues discussed in this paper include the nozzle, splash mitigation in the mercury pool, the mercury containment vessel, and the mercury recirculation system.« less

  1. Melt damage simulation of W-macrobrush and divertor gaps after multiple transient events in ITER

    NASA Astrophysics Data System (ADS)

    Bazylev, B. N.; Janeschitz, G.; Landman, I. S.; Loarte, A.; Pestchanyi, S. E.

    2007-06-01

    Tungsten in the form of macrobrush structure is foreseen as one of two candidate materials for the ITER divertor and dome. In ITER, even for moderate and weak ELMs when a thin shielding layer does not protect the armour surface from the dumped plasma, the main mechanisms of metallic target damage remain surface melting and melt motion erosion, which determines the lifetime of the plasma facing components. The melt erosion of W-macrobrush targets with different geometry of brush surface under the heat loads caused by weak ELMs is numerically investigated using the modified code MEMOS. The optimal angle of brush surface inclination that provides a minimum of surface roughness is estimated for given inclination angles of impacting plasma stream and given parameters of the macrobrush target. For multiple disruptions the damage of the dome gaps and the gaps between divertor cassettes caused by the radiation impact is estimated.

  2. Dental Office Waste – Public Health and Ecological Risk

    PubMed Central

    Muhamedagic, Belma; Muhamedagic, Lejla; Masic, Izet

    2009-01-01

    CONFLICT OF INTEREST: NONE DECLARED Waste management is one of the key ecological challenges of the modern world. As dental practitioners, we must recognize that some of the materials and procedures we use to provide dental health services may present challenges to the environment. Realizing this, we can begin to take measures to minimize the production of these wastes and their potential environmental effects. Dental office waste typically cause toxic chemicals to enter our streams, sewers, and landfills. This paper identifies some common wastes produced by dental offices (dental amalgam, silver, lead, biomedical and general office waste) and provides practical suggestions for reducing the impact of our profession on the environment. To dispose of dental wastes, if recycling is not an option, proper disposal as hazardous waste is necessary. But, problem is that dental waste is in most cases dumped at uncontrolled disposal sites, and that is public health and ecological risk. PMID:24133379

  3. Analysis the Purposes of Land Use Planning on the Hard Coal Tailing Dumps

    NASA Astrophysics Data System (ADS)

    Zástĕrová, Petra; Niemiec, Dominik; Marschalko, Marian; Durd'ák, Jan; Duraj, Miloš; Yilmaz, Işik; Drusa, Marian

    2016-10-01

    The aim of this publication is to analyse the purposes of land use planning on hard coal tailing dumps. This issue is very topical because there are 46 tailing dumps and 281 reservoirs in the Ostrava-Karvina Mining District. They significantly affect the landscape of this region. A major problem is solving problems of reclamation of these geological environment. This means that it is necessary to think about it and start to solve it. It is clear that such reclamation is not simple both economic as well as environmental point of view. It is necessary to think carefully about what purpose would be tailing dump or reservoirs to utilize in a given location.

  4. Quantum switching of π-electron rotations in a nonplanar chiral molecule by using linearly polarized UV laser pulses.

    PubMed

    Mineo, Hirobumi; Yamaki, Masahiro; Teranishi, Yoshiaki; Hayashi, Michitoshi; Lin, Sheng Hsien; Fujimura, Yuichi

    2012-09-05

    Nonplanar chiral aromatic molecules are candidates for use as building blocks of multidimensional switching devices because the π electrons can generate ring currents with a variety of directions. We employed (P)-2,2'-biphenol because four patterns of π-electron rotations along the two phenol rings are possible and theoretically determine how quantum switching of the π-electron rotations can be realized. We found that each rotational pattern can be driven by a coherent excitation of two electronic states under two conditions: one is the symmetry of the electronic states and the other is their relative phase. On the basis of the results of quantum dynamics simulations, we propose a quantum control method for sequential switching among the four rotational patterns that can be performed by using ultrashort overlapped pump and dump pulses with properly selected relative phases and photon polarization directions. The results serve as a theoretical basis for the design of confined ultrafast switching of ring currents of nonplanar molecules and further current-induced magnetic fluxes of more sophisticated systems.

  5. Linearized compressible-flow theory for sonic flight speeds

    NASA Technical Reports Server (NTRS)

    Heaslet, Max A; Lomax, Harvard; Spreiter, John R

    1950-01-01

    The partial differential equation for the perturbation velocity potential is examined for free-stream Mach numbers close to and equal to one. It is found that, under the assumptions of linearized theory, solutions can be found consistent with the theory for lifting-surface problems both in stationary three-dimensional flow and in unsteady two-dimensional flow. Several examples are solved including a three dimensional swept-back wing and two dimensional harmonically-oscillating wing, both for a free stream Mach number equal to one. Momentum relations for the evaluation of wave and vortex drag are also discussed. (author)

  6. Apraxia and the Parietal Lobes

    ERIC Educational Resources Information Center

    Goldenberg, Georg

    2009-01-01

    The widely held belief in a central role of left parietal lesions for apraxia can be traced back to Liepmann's model of a posterior to anterior stream converting mental images of intended action into motor execution. Although this model has undergone significant changes, its modern descendants still attribute the parietal contribution to the…

  7. Theory and simulation of backbombardment in single-cell thermionic-cathode electron guns

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Edelen, J.  P.; Biedron, S.  G.; Harris, J.  R.

    This paper presents a comparison between simulation results and a first principles analytical model of electron back-bombardment developed at Colorado State University for single-cell, thermionic-cathode rf guns. While most previous work on back-bombardment has been specific to particular accelerator systems, this work is generalized to a wide variety of guns within the applicable parameter space. The merits and limits of the analytic model will be discussed. This paper identifies the three fundamental parameters that drive the back-bombardment process, and demonstrates relative accuracy in calculating the predicted back-bombardment power of a single-cell thermionic gun.

  8. Theory and simulation of backbombardment in single-cell thermionic-cathode electron guns

    DOE PAGES

    Edelen, J.  P.; Biedron, S.  G.; Harris, J.  R.; ...

    2015-04-01

    This paper presents a comparison between simulation results and a first principles analytical model of electron back-bombardment developed at Colorado State University for single-cell, thermionic-cathode rf guns. While most previous work on back-bombardment has been specific to particular accelerator systems, this work is generalized to a wide variety of guns within the applicable parameter space. The merits and limits of the analytic model will be discussed. This paper identifies the three fundamental parameters that drive the back-bombardment process, and demonstrates relative accuracy in calculating the predicted back-bombardment power of a single-cell thermionic gun.

  9. Dynamics of streaming instability with quantum correction

    NASA Astrophysics Data System (ADS)

    Goutam, H. P.; Karmakar, P. K.

    2017-05-01

    A modified quantum hydrodynamic model (m-QHD) is herein proposed on the basis of the Thomas-Fermi (TF) theory of many fermionic quantum systems to investigate the dynamics of electrostatic streaming instability modes in a complex (dusty) quantum plasma system. The newly formulated m-QHD, as an amelioration over the existing usual QHD, employs a dimensionality-dependent Bohmian quantum correction prefactor, γ = [(D-2)/3D], in the electron quantum dynamics, where D symbolizing the problem dimensionality under consideration. The normal mode analysis of the coupled structure equations reveals the excitation of two distinct streaming modes associated with the flowing ions (against electrons and dust) and the flowing dust particulates (against the electrons and ions). It is mainly shown that the γ-factor introduces a new source of stability and dispersive effects to the ion-streaming instability solely; but not to the dust counterparts. A non-trivial application of our investigation in electrostatic beam-plasma (flow-driven) coupled dynamics leading to the development of self-sustained intense electric current, and hence, of strong magnetic field in compact astrophysical objects (in dwarf-family stars) is summarily indicated.

  10. Geo-Chip analysis reveals reduced functional diversity of the bacterial community at a dumping site for dredged Elbe sediment.

    PubMed

    Störmer, Rebecca; Wichels, Antje; Gerdts, Gunnar

    2013-12-15

    The dumping of dredged sediments represents a major stressor for coastal ecosystems. The impact on the ecosystem function is determined by its complexity not easy to assess. In the present study, we evaluated the potential of bacterial community analyses to act as ecological indicators in environmental monitoring programmes. We investigated the functional structure of bacterial communities, applying functional gene arrays (GeoChip4.2). The relationship between functional genes and environmental factors was analysed using distance-based multivariate multiple regression. Apparently, both the function and structure of the bacterial communities are impacted by dumping activities. The bacterial community at the dumping centre displayed a significant reduction of its entire functional diversity compared with that found at a reference site. DDX compounds separated bacterial communities of the dumping site from those of un-impacted sites. Thus, bacterial community analyses show great potential as ecological indicators in environmental monitoring. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. The evidence of toxic wastes dumping in Campania, Italy.

    PubMed

    Marfe, Gabriella; Di Stefano, Carla

    2016-09-01

    The region of Campania (particularly Naples and Caserta) were subjected to extensive illegal dumping operations of toxic and radioactive wastes since the 1980s. The highly toxic wastes (HTW) dumping operations that have taken place both along the coast and the hinterland, have extremely adverse effects on health, livelihoods and the future prospect of sustainable development of the local population. The toxic wastes dumping in Campania is real and it has compromised (irreversibly) the human health, natural environment, food security and the long-term development prospects of the affected population. To reverse this tragic trend, it is necessery the identification, isolation and reclamation of the polluted sites and full assessment of the nature and the scale of the polluting chemicals and other hazardous wastes. The purpose of this review is to contribute significantly to the available evidence of the long-running toxic waste dumping in Campania and its negative impact on the health of population. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Neutral beam dump with cathodic arc titanium gettering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smirnov, A.; Korepanov, S. A.; Putvinski, S.

    An incomplete neutral beam capture can degrade the plasma performance in neutral beam driven plasma machines. The beam dumps mitigating the shine-through beam recycling must entrap and retain large particle loads while maintaining the beam-exposed surfaces clean of the residual impurities. The cathodic arc gettering, which provides high evaporation rate coupled with a fast time response, is a powerful and versatile technique for depositing clean getter films in vacuum. A compact neutral beam dump utilizing the titanium arc gettering was developed for a field-reversed configuration plasma sustained by 1 MW, 20-40 keV neutral hydrogen beams. The titanium evaporator features amore » new improved design. The beam dump is capable of handling large pulsed gas loads, has a high sorption capacity, and is robust and reliable. With the beam particle flux density of 5 x 10{sup 17} H/(cm{sup 2}s) sustained for 3-10 ms, the beam recycling coefficient, defined as twice the ratio of the hydrogen molecular flux leaving the beam dump to the incident flux of high-energy neutral atoms, is {approx}0.7. The use of the beam dump allows us to significantly reduce the recycling of the shine-through neutral beam as well as to improve the vacuum conditions in the machine.« less

  13. Reverse Current in Solar Flares

    NASA Technical Reports Server (NTRS)

    Knight, J. W.; Sturrock, P. A.

    1976-01-01

    The theory that impulsive X ray bursts are produced by high energy electrons streaming from the corona to the chromosphere is investigated. Currents associated with these streams are so high that either the streams do not exist or their current is neutralized by a reverse current. Analysis of a simple model indicates that the primary electron stream leads to the development of an electric field in the ambient corona which decelerates the primary beam and produces a neutralizing reverse current. It appears that, in some circumstances, this electric field could prevent the primary beam from reaching the chromosphere. In any case, the electric field acts as an energy exchange mechanism, extracting kinetic energy from the primary beam and using it to heat the ambient plasma. This heating is typically so rapid that it must be expected to have important dynamical consequences.

  14. Cosmic Ray Streaming in Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Wiener, Joshua; Gould Zweibel, Ellen; Oh, Siang P.

    2017-08-01

    The origin of diffuse radio emission in galaxy clusters remains an open question in astrophysics. This emission indicates the presence of cluster-wide magnetic fields and high energy cosmic ray (CR) electrons. I will discuss how the properties of the observed radio emission in clusters are shaped by different CR transport processes, namely CR streaming. Recent work has shown that fast streaming may turn off radio emission on relatively short time scales - a full treatment of magnetohydrodynamic (MHD) wave damping shows that streaming may be even faster than previously thought in high β environments. I will briefly introduce the physics behind CR transport, and present simple numerical simulations of the Coma cluster that predict radio emission, as well as other observable signatures such as gamma radiation that can differentiate between models for the source of the CR electrons.

  15. Two stream instability in n-type gallium arsenide semiconductor quantum plasma

    NASA Astrophysics Data System (ADS)

    Ghosh, S.; Muley, Apurva

    2018-01-01

    By using quantum hydrodynamic model, we derive a generalized dielectric response function for two stream instability (convective only) in n-type gallium arsenide semiconductor plasma. We investigate the phase and amplification profiles of two stream instability with externally applied electric field ranging from 2600 to 4000 kV m-1 in presence of non-dimensional quantum parameter- H. In this range, a significant number of electrons in satellite valley become comparable to the number of electrons in central valley. The presence of quantum corrections in plasma medium induces two novel modes; one of it has amplifying nature and propagates in forward direction. It also modifies the spectral profile of four pre-existing modes in classical plasma. The existence of two stream instability is also established analytically by deriving the real part of longitudinal electrokinetic power flow density.

  16. Spatial dependency of V. cholera prevalence on open space refuse dumps in Kumasi, Ghana: a spatial statistical modelling

    PubMed Central

    Osei, Frank B; Duker, Alfred A

    2008-01-01

    Background Cholera has persisted in Ghana since its introduction in the early 70's. From 1999 to 2005, the Ghana Ministry of Health officially reported a total of 26,924 cases and 620 deaths to the WHO. Etiological studies suggest that the natural habitat of V. cholera is the aquatic environment. Its ability to survive within and outside the aquatic environment makes cholera a complex health problem to manage. Once the disease is introduced in a population, several environmental factors may lead to prolonged transmission and secondary cases. An important environmental factor that predisposes individuals to cholera infection is sanitation. In this study, we exploit the importance of two main spatial measures of sanitation in cholera transmission in an urban city, Kumasi. These are proximity and density of refuse dumps within a community. Results A spatial statistical modelling carried out to determine the spatial dependency of cholera prevalence on refuse dumps show that, there is a direct spatial relationship between cholera prevalence and density of refuse dumps, and an inverse spatial relationship between cholera prevalence and distance to refuse dumps. A spatial scan statistics also identified four significant spatial clusters of cholera; a primary cluster with greater than expected cholera prevalence, and three secondary clusters with lower than expected cholera prevalence. A GIS based buffer analysis also showed that the minimum distance within which refuse dumps should not be sited within community centres is 500 m. Conclusion The results suggest that proximity and density of open space refuse dumps play a contributory role in cholera infection in Kumasi. PMID:19087235

  17. International Arctic Seas Assessment Project.

    PubMed

    Sjöblom, K L; Salo, A; Bewers, J M; Cooper, J; Dyer, R S; Lynn, N M; Mount, M E; Povinec, P P; Sazykina, T G; Schwarz, J; Scott, E M; Sivintsev, Y V; Tanner, J E; Warden, J M; Woodhead, D

    1999-09-30

    The International Atomic Energy Agency responded to the news that the former Soviet Union had dumped radioactive wastes in the shallow waters of the Arctic Seas, by launching the International Arctic Seas Assessment Project in 1993. The project had two objectives: to assess the risks to human health and to the environment associated with the radioactive wastes dumped in the Kara and Barents Seas; and to examine possible remedial actions related to the dumped wastes and to advise on whether they are necessary and justified. The current radiological situation in the Arctic waters was examined to assess whether there is any evidence for releases from the dumped waste. Potential future releases from the dumped wastes were predicted, concentrating on the high-level waste objects containing the major part of the radionuclide inventory of the wastes. Environmental transport of released radionuclides was modelled and the associated radiological impact on humans and the biota was assessed. The feasibility, costs and benefits of possible remedial measures applied to a selected high-level waste object were examined. Releases from identified dumped objects were found to be small and localised to the immediate vicinity of the dumping sites. Projected future annual doses to members of the public in typical local population groups were very small, less than 1 microSv--corresponding to a trivial risk. Projected future doses to a hypothetical group of military personnel patrolling the foreshore of the fjords in which wastes have been dumped were higher, up to 4 mSv/year, which still is of the same order as the average annual natural background dose. Moreover, since any of the proposed remedial actions were estimated to cost several million US$ to implement, remediation was not considered justified on the basis of potentially removing a collective dose of 10 man Sv. Doses calculated to marine fauna were insignificant, orders of magnitude below those at which detrimental effects on fauna populations might be expected to occur. Remediation was thus concluded not to be warranted on radiological grounds.

  18. Modelling reactive transport in a phosphogypsum dump, Venezia, Italia

    NASA Astrophysics Data System (ADS)

    Calcara, Massimo; Borgia, Andrea; Cattaneo, Laura; Bartolo, Sergio; Clemente, Gianni; Glauco Amoroso, Carlo; Lo Re, Fabio; Tozzato, Elena

    2013-04-01

    We develop a reactive-transport porous media flow model for a phosphogypsum dump located on the intertidal deposits of the Venetian Lagoon: 1. we construct a complex conceptual and geologic model from field data using the GMS™ graphical user interface; 2. the geological model is mapped onto a rectangular MODFLOW grid; 3. using the TMT2 FORTRAN90 code we translate this grid into the MESH, INCON and GENER input files for the TOUGH2 series of codes; 4. we run TOUGH-REACT to model flow and reactive transport in the dump and the sediments below it. The model includes 3 different dump materials (phosphogypsum, bituminous and hazardous wastes) with the pores saturated by specific fluids. The sediments below the dump are formed by an intertidal sequence of calcareous sands and silts, in addition to clays and organic deposits, all of which are initially saturated with lagoon salty waters. The recharge rain-water dilutes the dump fluids. In turn, the percolates from the dump react with the underlying sediments and the sea water that saturates them. Simulation results have been compared with chemical sampled analyses. In fact, in spite of the simplicity of our model we are able to show how the pH becomes neutral at a short distance below the dump, a fact observed during aquifer monitoring. The spatial and temporal evolution of dissolution and precipitation reactions occur in our model much alike reality. Mobility of some elements, such as divalent iron, are reduced by specific and concurrent conditions of pH from near-neutrality to moderately high values and positive redox potential; opposite conditions favour mobility of potentially toxic metals such as Cr, As Cd and Pb. Vertical movement are predominant. Trend should be therefore heavily influenced by pH and Eh values. If conditions are favourable to mobility, concentration of these substances in the bottom strata could be high. However, simulation suggest that the sediments tend to reduce the transport potential of contaminants.

  19. Preparation of X-ray astronomy satellite experiment Development of computer programs for the Salyut-HEXE X-ray experiment ground station

    NASA Astrophysics Data System (ADS)

    Petrik, J.

    The engineering model of the Salyut-HEXE experiment is described. The detector system, electronics box, and ground station are addressed. The microprocessor system is considered, discussing the cards and presenting block diagrams of their functions. The telemetry is examined, including the various modes and the direct and indirect transmission modes. The ground station programs are discussed, including the tasks, program development, input and output programs, status, power supply, count rates, telemetry dump, hard copy, and checksum.

  20. Multi-frequency klystron designed for high efficiency

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jensen, Aaron

    A multi-frequency klystron has an electron gun which generates a beam, a circuit of bunch-align-collect (BAC) tuned cavities that bunch the beam and amplify an RF signal, a collector where the beam is collected and dumped, and a standard output cavity and waveguide coupled to a window to output RF power at a fundamental mode to an external load. In addition, the klystron has additional bunch-align-collect (BAC) cavities tuned to a higher harmonic frequency, and a harmonic output cavity and waveguide coupled via a window to an additional external load.

  1. 2C-R4WM Spectroscopy of Jet Cooled NO_3

    NASA Astrophysics Data System (ADS)

    Fukushima, Masaru; Ishiwata, Takashi; Hirota, Eizi

    2016-06-01

    We have generated NO_3 from pyrolysis of N_2O_5 following supersonic free jet expansion, and carried out two color resonant four wave mixing ( 2C-R4WM ) spectroscopy of the tilde{B} ^2E' - tilde{X} ^2A_2' electronic transition. One laser was fixed to pump NO_3 to a ro-vibronic level of the tilde{B} state, and the other laser ( probe ) was scanned across two levels of the tilde{X} ^2A_2' state lying at 1051 and 1492 cm-1, the ν_1 (a_1') and ν_3 (e') fundamentals, respectively. The 2C-R4WM spectra have unexpected back-ground signal of NO_3 ( stray signal due to experimental set-up is also detected ) similar to laser induced fluorescence ( LIF ) excitation spectrum of the 0-0 band, although the back-ground signal was not expected in considering the 2C-R4WM scheme. Despite the back-ground interference, we have observed two peaks at 1051.61 and 1055.29 cm-1 in the ν_1 region of the spectrum, and the frequencies agree with the two bands, 1051.2 and 1055.3 cm-1, of our relatively higher resolution dispersed fluorescence spectrum, the former of which has been assigned to the ν_1 fundamental. Band width of both peaks, ˜ 0.2 cm-1, is broader than twice the experimental spectral-resolution, 0.04 cm-1 ( because this experiment is double resonance spectroscopy ), and the 1051.61 cm-1 peak is attributed to a Q branch band head ( a line-like Q branch ) of the ν_1 fundamental. The other branches are suspected to be hidden in noise of the back-ground signal. The 1055.29 cm-1 peak is also attributed to a Q band head. The tilde{B} ^2E'1/2 ( J' = 3/2, K' = 1 ) - tilde{X} ^2A_2' ( N'' = 1, K'' = 0 ) ro-vibronic transition was used as the pump transition. The dump ( probe ) transition to both a_1' and e' vibronic levels are then allowed as perpendicular transition. Accordingly, it cannot be determined from present results whether the 1055.29 cm-1 band is attributed to a_1' or e' (ν_3), unfortunately. The 2C-R4WM spectrum of the 1492 cm-1 band region shows one Q head at 1499.79 cm-1, which is consistent with our dispersed fluorescence spectrum. By considering with the ν_3 + ν_4 - ν_4 hot band, the present results suggest that both 1055.29 and 1499.79 cm-1 levels are a_1' level. K. Kawaguchi et al., J. Phys. Chem. A 117, 13732 (2013) and E. Hirota, J. Mol. Spectrosco. 310, 99 (2015).

  2. Development of organic fertilizers from food market waste and urban gardening by composting in Ecuador

    PubMed Central

    Jara-Samaniego, J.; Pérez-Murcia, M. D.; Bustamante, M. A.; Paredes, C.; Pérez-Espinosa, A.; Gavilanes-Terán, I.; López, M.; Marhuenda-Egea, F. C.; Brito, H.; Moral, R.

    2017-01-01

    Currently, the management of urban waste streams in developing countries is not optimized yet, and in many cases these wastes are disposed untreated in open dumps. This fact causes serious environmental and health problems due to the presence of contaminants and pathogens. Frequently, the use of specific low-cost strategies reduces the total amount of wastes. These strategies are mainly associated to the identification, separate collection and composting of specific organic waste streams, such as vegetable and fruit refuses from food markets and urban gardening activities. Concretely, in the Chimborazo Region (Ecuador), more than 80% of municipal solid waste is dumped into environment due to the lack of an efficient waste management strategy. Therefore, the aim of this study was to develop a demonstration project at field scale in this region to evaluate the feasibility of implanting the composting technology not only for the management of the organic waste fluxes from food market and gardening activities to be scaled-up in other developing regions, but also to obtain an end-product with a commercial value as organic fertilizer. Three co-composting mixtures were prepared using market wastes mixed with pruning of trees and ornamental palms as bulking agents. Two piles were created using different proportions of market waste and prunings of trees and ornamental palms: pile 1 (50:33:17) with a C/N ratio 25; pile 2: (60:30:10) with C/N ratio 24 and pile 3 (75:0:25) with C/N ratio 33), prepared with market waste and prunings of ornamental palm. Throughout the process, the temperature of the mixtures was monitored and organic matter evolution was determined using thermogravimetric and chemical techniques. Additionally, physico-chemical, chemical and agronomic parameters were determined to evaluate compost quality. The results obtained indicated that all the piles showed a suitable development of the composting process, with a significant organic matter decomposition, reached in a shorter period of time in pile 3. At the end of the process, all the composts showed absence of phytotoxicity and suitable agronomic properties for their use as organic fertilizers. This reflects the viability of the proposed alternative to be scaled-up in developing areas, not only to manage and recycle urban waste fluxes, but also to obtain organic fertilizers, including added value in economic terms related to nutrient contents. PMID:28727757

  3. Development of organic fertilizers from food market waste and urban gardening by composting in Ecuador.

    PubMed

    Jara-Samaniego, J; Pérez-Murcia, M D; Bustamante, M A; Paredes, C; Pérez-Espinosa, A; Gavilanes-Terán, I; López, M; Marhuenda-Egea, F C; Brito, H; Moral, R

    2017-01-01

    Currently, the management of urban waste streams in developing countries is not optimized yet, and in many cases these wastes are disposed untreated in open dumps. This fact causes serious environmental and health problems due to the presence of contaminants and pathogens. Frequently, the use of specific low-cost strategies reduces the total amount of wastes. These strategies are mainly associated to the identification, separate collection and composting of specific organic waste streams, such as vegetable and fruit refuses from food markets and urban gardening activities. Concretely, in the Chimborazo Region (Ecuador), more than 80% of municipal solid waste is dumped into environment due to the lack of an efficient waste management strategy. Therefore, the aim of this study was to develop a demonstration project at field scale in this region to evaluate the feasibility of implanting the composting technology not only for the management of the organic waste fluxes from food market and gardening activities to be scaled-up in other developing regions, but also to obtain an end-product with a commercial value as organic fertilizer. Three co-composting mixtures were prepared using market wastes mixed with pruning of trees and ornamental palms as bulking agents. Two piles were created using different proportions of market waste and prunings of trees and ornamental palms: pile 1 (50:33:17) with a C/N ratio 25; pile 2: (60:30:10) with C/N ratio 24 and pile 3 (75:0:25) with C/N ratio 33), prepared with market waste and prunings of ornamental palm. Throughout the process, the temperature of the mixtures was monitored and organic matter evolution was determined using thermogravimetric and chemical techniques. Additionally, physico-chemical, chemical and agronomic parameters were determined to evaluate compost quality. The results obtained indicated that all the piles showed a suitable development of the composting process, with a significant organic matter decomposition, reached in a shorter period of time in pile 3. At the end of the process, all the composts showed absence of phytotoxicity and suitable agronomic properties for their use as organic fertilizers. This reflects the viability of the proposed alternative to be scaled-up in developing areas, not only to manage and recycle urban waste fluxes, but also to obtain organic fertilizers, including added value in economic terms related to nutrient contents.

  4. Alternative backing up pump for turbomolecular pumps

    DOEpatents

    Myneni, Ganapati Rao

    2003-04-22

    As an alternative to the use of a mechanical backing pump in the application of wide range turbomolecular pumps in ultra-high and extra high vacuum applications, palladium oxide is used to convert hydrogen present in the evacuation stream and related volumes to water with the water then being cryo-pumped to a low pressure of below about 1.e.sup.-3 Torr at 150.degree. K. Cryo-pumping is achieved using a low cost Kleemenco cycle cryocooler, a somewhat more expensive thermoelectric cooler, a Venturi cooler or a similar device to achieve the required minimization of hydrogen partial pressure.

  5. Control apparatus and method for efficiently heating a fuel processor in a fuel cell system

    DOEpatents

    Doan, Tien M.; Clingerman, Bruce J.

    2003-08-05

    A control apparatus and method for efficiently controlling the amount of heat generated by a fuel cell processor in a fuel cell system by determining a temperature error between actual and desired fuel processor temperatures. The temperature error is converted to a combustor fuel injector command signal or a heat dump valve position command signal depending upon the type of temperature error. Logic controls are responsive to the combustor fuel injector command signals and the heat dump valve position command signal to prevent the combustor fuel injector command signal from being generated if the heat dump valve is opened or, alternately, from preventing the heat dump valve position command signal from being generated if the combustor fuel injector is opened.

  6. PLASMA EMISSION BY COUNTER-STREAMING ELECTRON BEAMS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ziebell, L. F.; Petruzzellis, L. T.; Gaelzer, R.

    2016-02-10

    The radiation emission mechanism responsible for both type-II and type-III solar radio bursts is commonly accepted as plasma emission. Recently Ganse et al. suggested that type-II radio bursts may be enhanced when the electron foreshock geometry of a coronal mass ejection contains a double hump structure. They reasoned that the counter-streaming electron beams that exist between the double shocks may enhance the nonlinear coalescence interaction, thereby giving rise to more efficient generation of radiation. Ganse et al. employed a particle-in-cell simulation to study such a scenario. The present paper revisits the same problem with EM weak turbulence theory, and showmore » that the fundamental (F) emission is not greatly affected by the presence of counter-streaming beams, but the harmonic (H) emission becomes somewhat more effective when the two beams are present. The present finding is thus complementary to the work by Ganse et al.« less

  7. Oscillating two-stream instability in a magnetized electron-positron-ion plasma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tinakiche, Nouara; Faculty of Physics, U.S.T.H.B, Algiers 16111; Annou, R.

    2015-04-15

    Oscillating two-stream instability (OTSI) in a magnetized electron-ion plasma has been thoroughly studied, e.g., in ionospheric heating experiments [C. S. Liu and V. K. Tripathi, Interaction of Electromagnetic Waves With Electron Beams and Plasmas (World Scientific, 1994); V. K. Tripathi and P. V. Siva Rama Prasad, J. Plasma Phys. 41, 13 (1989); K. Ramachandran and V. K. Tripathi, IEEE Trans. Plasma Sci. 25, 423 (1997)]. In this paper, OTSI is investigated in a magnetized electron-positron-ion plasma. The dispersion relation of the process is established. The pump field threshold, along with the maximum growth rate of the instability is assessed usingmore » the Arecibo and HAARP parameters.« less

  8. Oscillating two-stream instability in a magnetized electron-positron-ion plasma

    NASA Astrophysics Data System (ADS)

    Tinakiche, Nouara; Annou, R.

    2015-04-01

    Oscillating two-stream instability (OTSI) in a magnetized electron-ion plasma has been thoroughly studied, e.g., in ionospheric heating experiments [C. S. Liu and V. K. Tripathi, Interaction of Electromagnetic Waves With Electron Beams and Plasmas (World Scientific, 1994); V. K. Tripathi and P. V. Siva Rama Prasad, J. Plasma Phys. 41, 13 (1989); K. Ramachandran and V. K. Tripathi, IEEE Trans. Plasma Sci. 25, 423 (1997)]. In this paper, OTSI is investigated in a magnetized electron-positron-ion plasma. The dispersion relation of the process is established. The pump field threshold, along with the maximum growth rate of the instability is assessed using the Arecibo and HAARP parameters.

  9. Dissection of Rovibronic Structure by Polarization-Resolved Two-Color Resonant Four-Wave Mixing Spectroscopy

    NASA Astrophysics Data System (ADS)

    Murdock, Daniel; Burns, Lori A.; Vaccaro, Patrick H.

    2009-08-01

    A synergistic theoretical and experimental investigation of stimulated emission pumping (SEP) as implemented in the coherent framework of two-color resonant four-wave mixing (TC-RFWM) spectroscopy is presented, with special emphasis directed toward the identification of polarization geometries that can distinguish spectral features according to their attendant changes in rotational quantum numbers. A vector-recoupling formalism built upon a perturbative treatment of matter-field interactions and a state-multipole expansion of the density operator allowed the weak-field signal intensity to be cast in terms of a TC-RFWM response tensor, RQ(K)(ɛ4*ɛ3ɛ2*ɛ1;Jg,Je,Jh,Jf), which separates the transverse characteristics of the incident and generated electromagnetic waves (ɛ4*ɛ3ɛ2*ɛ1) from the angular momentum properties of the PUMP and DUMP resonances (Jg,Je,Jh,Jf). For an isolated SEP process induced in an isotropic medium, the criteria needed to discriminate against subsets of rovibronic structure were encoded in the roots of a single tensor element, R0(0)(ɛ4*ɛ3ɛ2*ɛ1;Jg,Je,Jh,Je). By assuming all optical fields to be polarized linearly and invoking the limit of high quantum numbers, specific angles of polarization for the detected signal field were found to suppress DUMP resonances selectively according to the nature of their rotational branch and the rotational branch of the meshing PUMP line. These predictions were corroborated by performing SEP measurements on the ground electronic potential energy surface of tropolone in two distinct regimes of vibrational excitation, with the near-ultraviolet Ã1B2-X˜1A1 (π* ← π) absorption system affording the requisite PUMP and DUMP transitions.

  10. Dissection of rovibronic structure by polarization-resolved two-color resonant four-wave mixing spectroscopy.

    PubMed

    Murdock, Daniel; Burns, Lori A; Vaccaro, Patrick H

    2009-11-26

    A synergistic theoretical and experimental investigation of stimulated emission pumping (SEP) as implemented in the coherent framework of two-color resonant four-wave mixing (TC-RFWM) spectroscopy is presented, with special emphasis directed toward the identification of polarization geometries that can distinguish spectral features according to their attendant changes in rotational quantum numbers. A vector-recoupling formalism built upon a perturbative treatment of matter-field interactions and a state-multipole expansion of the density operator allowed the weak-field signal intensity to be cast in terms of a TC-RFWM response tensor, RQ(K)(epsilon4*epsilon3epsilon2*epsilon1;Jg,Je,Jh,Jf), which separates the transverse characteristics of the incident and generated electromagnetic waves (epsilon4*epsilon3epsilon2*epsilon1) from the angular momentum properties of the PUMP and DUMP resonances (Jg,Je,Jh,Jf). For an isolated SEP process induced in an isotropic medium, the criteria needed to discriminate against subsets of rovibronic structure were encoded in the roots of a single tensor element, R0(0)(epsilon4*epsilon3epsilon2*epsilon1;Jg,Je,Jh,Je). By assuming all optical fields to be polarized linearly and invoking the limit of high quantum numbers, specific angles of polarization for the detected signal field were found to suppress DUMP resonances selectively according to the nature of their rotational branch and the rotational branch of the meshing PUMP line. These predictions were corroborated by performing SEP measurements on the ground electronic potential energy surface of tropolone in two distinct regimes of vibrational excitation, with the near-ultraviolet 1B2-1A1 (pi*<--pi) absorption system affording the requisite PUMP and DUMP transitions.

  11. Influence of the backreaction of streaming cosmic rays on magnetic field generation and thermal instability

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nekrasov, Anatoly K.; Shadmehri, Mohsen, E-mail: anekrasov@ifz.ru, E-mail: nekrasov.anatoly@gmail.com, E-mail: m.shadmehri@gu.ac.ir

    2014-06-10

    Using a multifluid approach, we investigate streaming and thermal instabilities of the electron-ion plasma with homogeneous cold cosmic rays propagating perpendicular to the background magnetic field. Perturbations are also considered to be across the magnetic field. The backreaction of cosmic rays resulting in strong streaming instabilities is taken into account. It is shown that, for sufficiently short wavelength perturbations, the growth rates can exceed the growth rate of cosmic-ray streaming instability along the magnetic field, found by Nekrasov and Shadmehri, which is in turn considerably larger than the growth rate of the Bell instability. The thermal instability is shown notmore » to be subject to the action of cosmic rays in the model under consideration. The dispersion relation for the thermal instability has been derived, which includes sound velocities of plasma and cosmic rays and Alfvén and cosmic-ray streaming velocities. The relation between these parameters determines the kind of thermal instability ranging from the Parker to the Field instabilities. The results obtained can be useful for a more detailed investigation of electron-ion astrophysical objects, such as supernova remnant shocks, galaxy clusters, and others, including the dynamics of streaming cosmic rays.« less

  12. AMS measurements of 14C and 129I in seawater around radioactive waste dump sites

    NASA Astrophysics Data System (ADS)

    Povinec, P. P.; Oregioni, B.; Jull, A. J. T.; Kieser, W. E.; Zhao, X.-L.

    2000-10-01

    According to a recent IAEA compilation of inventories of radioactive wastes dumped in the world ocean, a total of 85 PBq of radioactive wastes were dumped, in the Atlantic (45 PBq), the Pacific (1.4 PBq) and the Arctic (38 PBq) Oceans and their marginal seas between 1946 and 1993, mostly in the form of low-level wastes. 3H, and 14C formed an important part of the beta-activity of these dumped wastes. Because of its long half-life, 14C will be the main constituent in possible leakages from the wastes in the future. On the other hand, 14C and 129I are important radioactive tracers which have been artificially introduced into the oceans. Small amounts of 14C and 129I can be easily measured by accelerator mass spectrometry (AMS) on mg-size samples of carbon and iodine extracted from 500 ml seawater samples. The high analytical sensitivity enables one therefore to find even trace amounts of 14C and 129I which could be released from radioactive wastes, and to compare the measured levels with the global distribution of these radionuclides. The IAEAs Marine Environment Laboratory (IAEA-MEL) has been engaged in an assessment program related to radioactive waste dumping in the oceans since 1992 and has participated in several expeditions to the Atlantic, Arctic, Indian and Pacific Oceans to sample seawater, biota and sediment for radiological assessment studies. In the present paper, we report on methods of 14C and 129I measurements in seawater by AMS and present data on the NE Atlantic, the Arctic and the NW Pacific Ocean dumping sites. A small increase of 14C was observed at the NE Atlantic dumping site.

  13. Avoidance of plants unsuitable for the symbiotic fungus in leaf-cutting ants: Learning can take place entirely at the colony dump.

    PubMed

    Arenas, Andrés; Roces, Flavio

    2017-01-01

    Plants initially accepted by foraging leaf-cutting ants are later avoided if they prove unsuitable for their symbiotic fungus. Plant avoidance is mediated by the waste produced in the fungus garden soon after the incorporation of the unsuitable leaves, as foragers can learn plant odors and cues from the damaged fungus that are both present in the recently produced waste particles. We asked whether avoidance learning of plants unsuitable for the symbiotic fungus can take place entirely at the colony dump. In order to investigate whether cues available in the waste chamber induce plant avoidance in naïve subcolonies, we exchanged the waste produced by subcolonies fed either fungicide-treated privet leaves or untreated leaves and measured the acceptance of untreated privet leaves before and after the exchange of waste. Second, we evaluated whether foragers could perceive the avoidance cues directly at the dump by quantifying the visits of labeled foragers to the waste chamber. Finally, we asked whether foragers learn to specifically avoid untreated leaves of a plant after a confinement over 3 hours in the dump of subcolonies that were previously fed fungicide-treated leaves of that species. After the exchange of the waste chambers, workers from subcolonies that had access to waste from fungicide-treated privet leaves learned to avoid that plant. One-third of the labeled foragers visited the dump. Furthermore, naïve foragers learned to avoid a specific, previously unsuitable plant if exposed solely to cues of the dump during confinement. We suggest that cues at the dump enable foragers to predict the unsuitable effects of plants even if they had never been experienced in the fungus garden.

  14. Avoidance of plants unsuitable for the symbiotic fungus in leaf-cutting ants: Learning can take place entirely at the colony dump

    PubMed Central

    Roces, Flavio

    2017-01-01

    Plants initially accepted by foraging leaf-cutting ants are later avoided if they prove unsuitable for their symbiotic fungus. Plant avoidance is mediated by the waste produced in the fungus garden soon after the incorporation of the unsuitable leaves, as foragers can learn plant odors and cues from the damaged fungus that are both present in the recently produced waste particles. We asked whether avoidance learning of plants unsuitable for the symbiotic fungus can take place entirely at the colony dump. In order to investigate whether cues available in the waste chamber induce plant avoidance in naïve subcolonies, we exchanged the waste produced by subcolonies fed either fungicide-treated privet leaves or untreated leaves and measured the acceptance of untreated privet leaves before and after the exchange of waste. Second, we evaluated whether foragers could perceive the avoidance cues directly at the dump by quantifying the visits of labeled foragers to the waste chamber. Finally, we asked whether foragers learn to specifically avoid untreated leaves of a plant after a confinement over 3 hours in the dump of subcolonies that were previously fed fungicide-treated leaves of that species. After the exchange of the waste chambers, workers from subcolonies that had access to waste from fungicide-treated privet leaves learned to avoid that plant. One-third of the labeled foragers visited the dump. Furthermore, naïve foragers learned to avoid a specific, previously unsuitable plant if exposed solely to cues of the dump during confinement. We suggest that cues at the dump enable foragers to predict the unsuitable effects of plants even if they had never been experienced in the fungus garden. PMID:28273083

  15. Reverse current in solar flares

    NASA Technical Reports Server (NTRS)

    Knight, J. W.; Sturrock, P. A.

    1977-01-01

    We examine the proposal that impulsive X-ray bursts are produced by high-energy electrons streaming from the corona to the chromosphere. It is known that the currents associated with these streams are so high that either the streams do not exist or their current is neutralized by a reverse current. Analysis of a simple model in which the reverse current is stable indicates that the primary electron stream leads to the development of an electric field in the ambient corona which (a) decelerates the primary beam and (b) produces a neutralizing reverse current. It appears that, in some circumstances, this electric field could prevent the primary beam from reaching the chromosphere. In any case, the electric field acts as an energy exchange mechanism, extracting kinetic energy from the primary beam and using it to heat the ambient plasma. This heating is typically so rapid that it must be expected to have important dynamical consequences.

  16. Bi-directional streaming of solar wind electrons greater than 80 eV - ISEE evidence for a closed-field structure within the driver gas of an interplanetary shock

    NASA Technical Reports Server (NTRS)

    Bame, S. J.; Asbridge, J. R.; Feldman, W. C.; Gosling, J. T.; Zwickl, R. D.

    1981-01-01

    In near time coincidence with the arrival of helium enriched plasma driving the shock wave disturbance of November 12-13, 1978, strong bi-directional streaming of solar wind electrons greater than about 80 eV was observed with Los Alamos instrumentation on ISEE 3. The streaming persisted for many hours simultaneously parallel and anti-parallel to the interplanetary magnetic field which was directed roughly perpendicular to the sun-satellite line. This example of bidirectional streaming cannot be explained by field line connection to the earth's bow shock or the outward propagating interplanetary shock which passed ISEE 3 approximately 16 hours earlier. The event is explained if the local interplanetary field was a part of a magnetic bottle rooted at the sun or a disconnected loop propagating outward.

  17. "Powerful Knowledge" Curriculum Theories and the Case of Physics

    ERIC Educational Resources Information Center

    Yates, Lyn; Millar, Victoria

    2016-01-01

    A stream of debate (including a previous special issue of this journal [25(1) 2014)] has made claims not just for "bringing knowledge back in" as the framing underpinning of the school curriculum, but that subjects associated with disciplinary and disciplined knowledge forms have a particular power and that these characteristics are…

  18. 30 CFR 57.9308 - Switch throws.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Loading, Hauling, and Dumping Safety Devices, Provisions, and Procedures for Roadways, Railroads, and Loading and Dumping Sites § 57...

  19. 30 CFR 57.9313 - Roadway maintenance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Loading, Hauling, and Dumping Safety Devices, Provisions, and Procedures for Roadways, Railroads, and Loading and Dumping Sites...

  20. 30 CFR 57.9317 - Suspended loads.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Loading, Hauling, and Dumping Safety Devices, Provisions, and Procedures for Roadways, Railroads, and Loading and Dumping Sites...

  1. 30 CFR 57.9305 - Truck spotters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Loading, Hauling, and Dumping Safety Devices, Provisions, and Procedures for Roadways, Railroads, and Loading and Dumping Sites § 57...

  2. Arsenic transport between surface and groundwater in a moderately reducing zone: Geochemical approach

    NASA Astrophysics Data System (ADS)

    Khaska, Mahmoud; Le Gal La Salle, Corinne; Verdoux, Patrick

    2015-04-01

    Arsenic contamination represents a major risk to human health as one of the most prominent environmental causes of cancer mortality. Mining activities, particularly those involving arsenic rich ores have an impact on the environment and on human health that may persist for many decades after mine closure. The relationships between As released from alluvial aquifer in the vicinity of the sulfide-rich mine dumps was demonstrated with geochemical and isotopic tracers (major and traces elements, 87Sr/86Sr, 18O, 2H). Strontium isotopes were used to trace the transport of As downstream from a As rich tailing dam. Increasing As and Fe concentrations in surface water are explained by As release associated with alluvial groundwater discharge to the stream. This process occurs in a moderately reduced section of the stream downgradient from the sulfide-rich tailing dam. High As, total Fe and low Eh in groundwater confirm the discharge of alluvial groundwater and explain its impact on surface water. Transport of As between surface and groundwater can be described as follows: 1- Subsurface moderately reducing conditions prevail in groundwater downgradient from the tailing dams. This suggests a flux of reduced water from sulfide-rich tailing dams which is characterized by its high As and Fe content resulting from the reduction of Fe-sulfides. 2- Upon mixing with surface water, oxidizing conditions prevails and precipitate as Fe hydroxide on the stream bed. As and Sr subsequently adsorbed on the Fe -oxyhydroxide surface. This process contributes to the immobilization of As in surface water. Remaining dissolved As in surface water can be re-introduced in alluvial groundwater downstream of the reducing zone.

  3. HIGH POWER BEAM DUMP AND TARGET / ACCELERATOR INTERFACE PROCEDURES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Blokland, Willem; Plum, Michael A; Peters, Charles C

    Satisfying operational procedures and limits for the beam target interface is a critical concern for high power operation at spallation neutron sources. At the Oak Ridge Spallation Neutron Source (SNS) a number of protective measures are instituted to ensure that the beam position, beam size and peak intensity are within acceptable limits at the target and high power Ring Injection Dump (RID). The high power beam dump typically handles up to 50 100 kW of beam power and its setup is complicated by the fact that there are two separate beam components simultaneously directed to the dump. The beam onmore » target is typically in the 800-1000 kW average power level, delivered in sub- s 60 Hz pulses. Setup techniques using beam measurements to quantify the beam parameters at the target and dump will be described. However, not all the instrumentation used for the setup and initial qualification is available during high power operation. Additional techniques are used to monitor the beam during high power operation to ensure the setup conditions are maintained, and these are also described.« less

  4. Influence of coal ash and slag dumping on dump waste waters of the Kostolac power plants (Serbia)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Popovic, A.; Djinovic, J.

    2006-10-01

    The content of selected trace and major elements in the river water used for transport, as well as in the subcategories of the waste waters (overflow and drainage) were analyzed in order to establish the influence of transport and dumping of coal ash and slag from the 'Kostolac A' and 'Kostolac B' power plants located 100 km from Belgrade (Serbia). It was found that during transport of coal ash and slag to the dump, the water used for transport becomes enriched with manganese, nickel, zinc, chromium, vanadium, titanium, cobalt, arsenic, aluminum, and silicon, while more calcium, iron, cadmium, and leadmore » are adsorbed by the ash and slag than is released from them. There is also an equilibrium between the release and adsorption processes of copper and magnesium during transport. The vertical penetration of the water used for transport results in a release of calcium, magnesium, manganese, and cadmium to the environment, while iron, nickel, zinc, chromium, copper, lead, vanadium, titanium, cobalt, and arsenic are adsorbed by the fractions of coal ash and slag in the dump.« less

  5. Feathered Detectives: Real-Time GPS Tracking of Scavenging Gulls Pinpoints Illegal Waste Dumping.

    PubMed

    Navarro, Joan; Grémillet, David; Afán, Isabel; Ramírez, Francisco; Bouten, Willem; Forero, Manuela G

    2016-01-01

    Urban waste impacts human and environmental health, and waste management has become one of the major challenges of humanity. Concurrently with new directives due to manage this human by-product, illegal dumping has become one of the most lucrative activities of organized crime. Beyond economic fraud, illegal waste disposal strongly enhances uncontrolled dissemination of human pathogens, pollutants and invasive species. Here, we demonstrate the potential of novel real-time GPS tracking of scavenging species to detect environmental crime. Specifically, we were able to detect illegal activities at an officially closed dump, which was visited recurrently by 5 of 19 GPS-tracked yellow-legged gulls (Larus michahellis). In comparison with conventional land-based surveys, GPS tracking allows a much wider and cost-efficient spatiotemporal coverage, even of the most hazardous sites, while GPS data accessibility through the internet enables rapid intervention. Our results suggest that multi-species guilds of feathered detectives equipped with GPS and cameras could help fight illegal dumping at continental scales. We encourage further experimental studies, to infer waste detection thresholds in gulls and other scavenging species exploiting human waste dumps.

  6. Feathered Detectives: Real-Time GPS Tracking of Scavenging Gulls Pinpoints Illegal Waste Dumping

    PubMed Central

    Grémillet, David; Afán, Isabel; Ramírez, Francisco; Bouten, Willem; Forero, Manuela G.

    2016-01-01

    Urban waste impacts human and environmental health, and waste management has become one of the major challenges of humanity. Concurrently with new directives due to manage this human by-product, illegal dumping has become one of the most lucrative activities of organized crime. Beyond economic fraud, illegal waste disposal strongly enhances uncontrolled dissemination of human pathogens, pollutants and invasive species. Here, we demonstrate the potential of novel real-time GPS tracking of scavenging species to detect environmental crime. Specifically, we were able to detect illegal activities at an officially closed dump, which was visited recurrently by 5 of 19 GPS-tracked yellow-legged gulls (Larus michahellis). In comparison with conventional land-based surveys, GPS tracking allows a much wider and cost-efficient spatiotemporal coverage, even of the most hazardous sites, while GPS data accessibility through the internet enables rapid intervention. Our results suggest that multi-species guilds of feathered detectives equipped with GPS and cameras could help fight illegal dumping at continental scales. We encourage further experimental studies, to infer waste detection thresholds in gulls and other scavenging species exploiting human waste dumps. PMID:27448048

  7. Emergence of kinetic behavior in streaming ultracold neutral plasmas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McQuillen, P.; Castro, J.; Bradshaw, S. J.

    2015-04-15

    We create streaming ultracold neutral plasmas by tailoring the photoionizing laser beam that creates the plasma. By varying the electron temperature, we control the relative velocity of the streaming populations, and, in conjunction with variation of the plasma density, this controls the ion collisionality of the colliding streams. Laser-induced fluorescence is used to map the spatially resolved density and velocity distribution function for the ions. We identify the lack of local thermal equilibrium and distinct populations of interpenetrating, counter-streaming ions as signatures of kinetic behavior. Experimental data are compared with results from a one-dimensional, two-fluid numerical simulation.

  8. Development and Evaluation of Ergonomic Interventions for Bucket Handling on Farms

    PubMed Central

    Fathallah, Fadi A.; Tang, Steven C.H.; Waters, Thomas R.

    2016-01-01

    Objective The aim of this study was to introduce and evaluate two interventions, Ergo Bucket Carrier (EBC) and Easy Lift (EL), for youths (and adults) to handle water/feed buckets on farms. Background The physical activities of both adult and youth farm workers contribute to the development of low-back disorders (LBDs). Many of the activities youths perform on farms are associated with increased LBD risk, particularly, the handling of water and feed buckets. Methods Seventeen adult and youth participants (10 males and seven females) participated in this study. To assess the risk of LBDs, the participants were instrumented with a three-dimensional spinal electrogoniometer while lifting, carrying, and dumping water buckets using traditional method and the two interventions. Results For both the adult and youth groups, the results showed that the two interventions significantly decrease the magnitudes of LBD risk in many of the tasks evaluated. Overall, the use of the EBC resulted in a 41% reduction in the level of LBD risk for the carrying task, and a reduction of 69% for the dumping task. Using the EL, on the other hand, is especially effective for lifting tasks (55% reduction in LBD risk). Results of the subjective response were consistent with the objective evaluations. Conclusion This study demonstrated the potential for ergonomic interventions in reducing LBD risk during the common farming task of bucket handling. Application Potential application of this study includes the introduction of the EBC and EL in family farms to reduce the LBD risk among youth and adult farmers. PMID:26994024

  9. Case study of a solid-waste-scavenger community with respect to health and environment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kungskulniti, Nipapun.

    1991-01-01

    This study was an investigation of a solid waste scavenger community at the On-Nooch Dump Site in Bangkok, Thailand. The purpose was to identify the dimensions of the public health conditions of solid waste scavengers and their community. Cross-sectional field surveys and measurements were undertaken to characterize the distribution and magnitude of health-related problems and environmental conditions. Scavengers were found to be exposed to hazardous conditions due to the waste materials at the dump site. Cuts and punctures from sharp materials were the most common complaints among scavengers. Health symptoms like headache, diarrhea, respiratory illness, skin diseases and back painmore » were also reported. There was a high prevalence of childhood respiratory illness especially among those children of households where cigarette smoking was present. Children had poor nutritional status and were commonly infected by intestinal protozoa and helminths. An appreciable proportion of adult respondents was below the normal range for lung function performance. Seroprevalence of HBV infection was found to be high among male respondents in addition to six respondents that had possible HIV infections. The quality of the community water supply was low. Air pollution measurements showed acceptable ambient air levels except for particulate levels (TSP and RSP). Levels of indoor, outdoor, and personal exposure NO{sub 2} were found to be similar. Data for an inner-city project apartment community named Din-Dang were also collected for comparison. A priority rating index and recommendations for public health condition improvements were presented.« less

  10. Box model of radionuclide dispersion and radiation risk estimation for population in case of radioactivity release from nuclear submarine {number_sign}601 dumped in the Kara Sea

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yefimov, E.I.; Pankratov, D.V.; Ignatiev, S.V.

    1997-12-31

    When ships with nuclear reactors or nuclear materials aboard suffer shipwreck or in the case of burial or dumping of radioactive wastes, atmospheric fallout, etc., radionuclides may be released and spread in the sea, contaminating the sea water and the sea bottom. When a nuclear submarine (NS) is dumped this spread of activity may occur due to gradual core destruction by corrosion over many years. The objective of this paper is to develop a mathematical model of radionuclide dispersion and to assess the population dose and radiation risk for radionuclide release from the NS No. 601, with Pb-Bi coolant thatmore » was dumped in the Kara Sea.« less

  11. Patient dumping, COBRA, and the public psychiatric hospital.

    PubMed

    Elliott, R L

    1993-02-01

    Serious clinical and risk management problems arise when indigent patients with acute medical conditions are transferred from general medical hospitals or emergency departments to public psychiatric hospitals that are ill equipped to provide medical care. To combat such practices, referred to as dumping, Congress included measures in the Consolidated Omnibus Budget Reconciliation Act of 1985 (COBRA) prohibiting such transfers. Because physicians and administrators in public psychiatric hospitals are generally not aware of the potential usefulness of COBRA in reducing dumping, this paper describes its important provisions. The key to preventing dumping is to educate referral sources to limitations on the medical care available at the receiving hospital and to discourage negligent patient transfers by enforcing COBRA. Public hospital staff and legal counsel who become familiar with COBRA's provisions can develop an antidumping strategy.

  12. Beam-induced back-streaming electron suppression analysis for an accelerator type neutron generator designed for 40Ar/39Ar geochronology.

    PubMed

    Waltz, Cory; Ayllon, Mauricio; Becker, Tim; Bernstein, Lee; Leung, Ka-Ngo; Kirsch, Leo; Renne, Paul; Bibber, Karl Van

    2017-07-01

    A facility based on a next-generation, high-flux D-D neutron generator has been commissioned and it is now operational at the University of California, Berkeley. The current generator designed for 40 Ar/ 39 Ar dating of geological materials produces nearly monoenergetic 2.45MeV neutrons at outputs of 10 8 n/s. The narrow energy range is advantageous relative to the 235 U fission spectrum neutrons due to (i) reduced 39 Ar recoil energy, (ii) minimized production of interfering argon isotopes from K, Ca, and Cl, and (iii) reduced total activity for radiological safety and waste generation. Calculations provided show that future conditioning at higher currents and voltages will allow for a neutron output of over 10 10 n/s, which is a necessary requirement for production of measurable quantities of 39 Ar through the reaction 39 K(n,p) 39 Ar. A significant problem encountered with increasing deuteron current was beam-induced electron backstreaming. Two methods of suppressing secondary electrons resulting from the deuterium beam striking the target were tested: the application of static electric and magnetic fields. Computational simulations of both techniques were done using a finite element analysis in COMSOL Multiphysics ® . Experimental tests verified these simulations. The most reliable suppression was achieved via the implementation of an electrostatic shroud with a voltage offset of -800V relative to the target. Copyright © 2017. Published by Elsevier Ltd.

  13. Ultrafast dynamics of isolated model photoactive yellow protein chromophores: "Chemical perturbation theory" in the laboratory.

    PubMed

    Vengris, Mikas; Larsen, Delmar S; van der Horst, Michael A; Larsen, Olaf F A; Hellingwerf, Klaas J; van Grondelle, Rienk

    2005-03-10

    Pump-probe and pump-dump probe experiments have been performed on several isolated model chromophores of the photoactive yellow protein (PYP). The observed transient absorption spectra are discussed in terms of the spectral signatures ascribed to solvation, excited-state twisting, and vibrational relaxation. It is observed that the protonation state has a profound effect on the excited-state lifetime of p-coumaric acid. Pigments with ester groups on the coumaryl tail end and charged phenolic moieties show dynamics that are significantly different from those of other pigments. Here, an unrelaxed ground-state intermediate could be observed in pump-probe signals. A similar intermediate could be identified in the sinapinic acid and in isomerization-locked chromophores by means of pump-dump probe spectroscopy; however, in these compounds it is less pronounced and could be due to ground-state solvation and/or vibrational relaxation. Because of strong protonation-state dependencies and the effect of electron donor groups, it is argued that charge redistribution upon excitation determines the twisting reaction pathway, possibly through interaction with the environment. It is suggested that the same pathway may be responsible for the initiation of the photocycle in native PYP.

  14. ABOUT the phenomenon produced by the successive jumps of the peripheric electrons, at the absorbtion of the intense photon beam by the metal

    NASA Astrophysics Data System (ADS)

    Isarie, Claudiu I.; Oprean, Constantin; Marginean, Ion; Nemes, Toderita; Isarie, Ilie V.; Bokor, Corina; Itu, Sorin

    2011-03-01

    When a photon beam is in impact with a metal, the peripheric electrons which belong to the bombarded material are made jumps, and in the same time, new photons are absorbed by electrons which had not time to come back to the fundamental levels. At a high level concentration of the radiant energy, a peripheral electron, could sequentially absorb more photons and could realize energetic jumps in succesive phase, equivalent with some photons of high energy which have wave-lenght smaller than the incidental photons. After some succesive photon absorbtion of the same electron, in the interval in which it is not activated by new photons, the electron comes back to the fundamental level and delivers the accumulated energy, in photons of higher energy, which have a lower energy than the incident beam. Comming back to the fundamental level, the electrons disturb the electronic cloud of the atom or ion they belong. After a huge number of such phenomenon the electronic cloud which is succesivelly disturbed, produces an oscillation which risez the temperature of the nucleus. The authors have studied the conditions which generated the rise of temperature and multiple radiations at the place where the photons bombard the metal.

  15. An ultrafast angle-resolved photoemission apparatus for measuring complex materials

    NASA Astrophysics Data System (ADS)

    Smallwood, Christopher L.; Jozwiak, Christopher; Zhang, Wentao; Lanzara, Alessandra

    2012-12-01

    We present technical specifications for a high resolution time- and angle-resolved photoemission spectroscopy setup based on a hemispherical electron analyzer and cavity-dumped solid state Ti:sapphire laser used to generate pump and probe beams, respectively, at 1.48 and 5.93 eV. The pulse repetition rate can be tuned from 209 Hz to 54.3 MHz. Under typical operating settings the system has an overall energy resolution of 23 meV, an overall momentum resolution of 0.003 Å-1, and an overall time resolution of 310 fs. We illustrate the system capabilities with representative data on the cuprate superconductor Bi2Sr2CaCu2O8+δ. The descriptions and analyses presented here will inform new developments in ultrafast electron spectroscopy.

  16. Laser control of electronic transitions of wave packet by using quadratically chirped pulses.

    PubMed

    Zou, Shiyang; Kondorskiy, Alexey; Mil'nikov, Gennady; Nakamura, Hiroki

    2005-02-22

    An effective scheme is proposed for the laser control of wave packet dynamics. It is demonstrated that by using specially designed quadratically chirped pulses, fast and nearly complete excitation of wave packet can be achieved without significant distortion of its shape. The parameters of the laser pulse can be estimated analytically from the Zhu-Nakamura theory of nonadiabatic transition. If the wave packet is not too narrow or not too broad, then the scheme is expected to be utilizable for multidimensional systems. The scheme is applicable to various processes such as simple electronic excitation, pump-dump, and selective bond breaking, and it is actually numerically demonstrated to work well by taking diatomic and triatomic molecules (LiH, NaK, H(2)O) as examples.

  17. Laser control of electronic transitions of wave packet by using quadratically chirped pulses

    NASA Astrophysics Data System (ADS)

    Zou, Shiyang; Kondorskiy, Alexey; Mil'nikov, Gennady; Nakamura, Hiroki

    2005-02-01

    An effective scheme is proposed for the laser control of wave packet dynamics. It is demonstrated that by using specially designed quadratically chirped pulses, fast and nearly complete excitation of wave packet can be achieved without significant distortion of its shape. The parameters of the laser pulse can be estimated analytically from the Zhu-Nakamura theory of nonadiabatic transition. If the wave packet is not too narrow or not too broad, then the scheme is expected to be utilizable for multidimensional systems. The scheme is applicable to various processes such as simple electronic excitation, pump-dump, and selective bond breaking, and it is actually numerically demonstrated to work well by taking diatomic and triatomic molecules (LiH, NaK, H2O) as examples.

  18. Dealing with emerging waste streams: used tyre assessment in Thailand using material flow analysis.

    PubMed

    Jacob, Paul; Kashyap, Prakriti; Suparat, Tasawan; Visvanathan, Chettiyappan

    2014-09-01

    Increasing urbanisation and automobile use have given rise to an increase in global tyre waste generation. A tyre becomes waste once it wears out and is no longer fit for its original purpose, and is thus in its end-of-life state. Unlike in developed countries, where waste tyre management has already become a significant issue, it is rarely a priority waste stream in developing countries. Hence, a large quantity of waste tyres ends up either in the open environment or in landfill. In Thailand, waste tyre management is in its infancy, with increased tyre production and wider use of vehicles, but low levels of recycling, leaving scope for more appropriate policies, plans and strategies to increase waste tyre recycling. This article describes the journey of waste tyres in Thailand in terms of recycling and recovery, and disposal. Material flow analysis was used as a tool to quantify the flows and accumulation of waste tyres in Thailand in 2012. The study revealed that, in Thailand in 2012, waste tyre management was still biased towards destructive technologies (48.9%), rather than material recovery involving rubber reclamation, retreading tyres and whole and shredded tyre applications (6.7%). Despite having both economic and environmental benefits, 44.4% of used tyres in 2012 were dumped in the open environment, and the remaining 0.05% in landfills. © The Author(s) 2014.

  19. Neutronics Assessments for a RIA Fragmentation Line Beam Dump Concept

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Boles, J L; Reyes, S; Ahle, L E

    Heavy ion and radiation transport calculations are in progress for conceptual beam dump designs for the fragmentation line of the proposed Rare Isotope Accelerator (RIA). Using the computer code PHITS, a preliminary design of a motor-driven rotating wheel beam dump and adjacent downstream multipole has been modeled. Selected results of these calculations are given, including neutron and proton flux in the wheel, absorbed dose and displacements per atom in the hub materials, and heating from prompt radiation and from decay heat in the multipole.

  20. Dispute Settlement in the World Trade Organization (WTO): An Overview

    DTIC Science & Technology

    2009-09-08

    this margin. “Zeroing” is a practice under which sales above fair value are disregarded or given a “zero” value, thus allowing the dumping margin to...be determined solely on the basis of less than fair value sales and, as alleged by some, improperly inflating the dumping margin. The Commerce...to determine the applicable dumping margin, i.e. the amount by which the price of an import when sold in the United States falls below the fair

Top