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Sample records for high water discharge

  1. High Conductivity Water Treatment Using Water Surface Discharge with Nonmetallic Electrodes

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoping; Zhang, Xingwang; Lei, Lecheng

    2013-06-01

    Although electrohydraulic discharge is effective for wastewater treatment, its application is restricted by water conductivity and limited to the treatment of low conductivity water. For high conductivity water treatment, water-surface discharge is the preferred choice. However, the metallic electrodes are easily corroded because of the high temperature and strong oxidative environment caused by gas phase discharge and the electrochemical reaction in water. As a result, the efficiency of the water treatment might be affected and the service life of the reactor might be shortened. In order to avoid the corrosion problem, nonmetallic electrode water-surface discharge is introduced into high conductivity water treatment in the present study. Carbon-felt and water were used as the high voltage electrode and ground electrode, respectively. A comparison of the electrical and chemical characteristics showed that nonmetallic electrode discharge maintained the discharge characteristics and enhanced the energy efficiency, and furthermore, the corrosion of metal electrodes was avoided.

  2. Flooding in Myanmar: joint occurrence of high discharges and high sea water levels?

    NASA Astrophysics Data System (ADS)

    Bouaziz, Laurène; Sperna Weiland, Frederiek; Vatvani, Deepak; Diermanse, Ferdinand

    2016-04-01

    In the summer of 2015 serious flooding occurred in Myanmar when cyclone Komen made landfall in Bangladesh, bringing strong winds and heavy rains to Myanmar. The cyclone struck the country during the monsoon season and resulted in widespread flooding, temporarily displacing over 1.6 million people. It was hypothesized that there could be a relation between occurrences of storm surges and extreme discharges in Myanmar. Comparable studies have shown that dependence between storm surge at Hoek van Holland in the Netherlands and high river discharges of the Rhine at Lobith exist with a lag of 6 days (Klerk et. al, 2015). The processes generating high discharges in the Ayeyarwady river and storm surges along the Myanmar coast were analyzed using global precipitation data (EU FP7 eartH2Observe), a distributed wflow-sbm hydrological model of the Ayeyarwady and a global storm surge model. About 15 historical tropical storms and hurricanes affecting Myanmar since 1992 were analyzed in terms of rainfall distribution over the country, discharged river flow volumes and storm surge extent and magnitude. All storms except for Komen in 2015 occurred between October and May, which does not coincide with the monsoon season (mainly June, July and August). The intensities and the paths of the 15 studied cyclones varied considerably and largely affected the spatial extent and the magnitude of storm surges. The study showed that high Ayeyarwady river flows and high surges generally do not coincide for the following reasons: the large scale of the river basin, the estimated one week travel time of water from the upstream catchment to the mouth, the occurrence of the majority of historical storms outside the monsoon season and the (relatively) limited spatial extent of a storm surge (at the scale of Myanmar). While the applied method is deemed successful for the identification of joint probabilities of surges and river discharges, this study indicates that such analyses are more relevant

  3. High resolution synoptic salinity mapping to identify groundwater--surface water discharges in lowland rivers.

    PubMed

    Pai, Henry; Villamizar, Sandra R; Harmon, Thomas C

    2015-04-21

    Quantifying distributed lateral groundwater contributions to surface water (GW-SW discharges) is a key aspect of tracking nonpoint-source pollution (NPSP) within a watershed. In this study, we characterized distributed GW-SW discharges and associated salt loading using elevated GW specific conductance (SC) as a tracer along a 38 km reach of the Lower Merced River in Central California. High resolution longitudinal surveys for multiple flows (1.3-150 m(3) s(-1)) revealed river SC gradients that mainly decreased with increasing flow, suggesting a dilution effect and/or reduced GW-SW discharges due to hydraulic gradient reductions. However, exceptions occurred (gradients increasing with increasing flow), pointing to complex spatiotemporal influences on GW-SW dynamics. The surveys revealed detailed variability in salinity gradients, from which we estimated distributed GW-SW discharge and salt loading using a simple mixing model. Modeled cumulative GW discharges for two surveys unaffected by ungauged SW discharges were comparable in magnitude to differential gauging-based discharge estimates and prior GW-SW studies along the same river reach. Ungauged lateral inlets and sparse GW data limited the study, and argue for enhancing monitoring efforts. Our approach provides a rapid and economical method for characterizing NPSP for gaining rivers in the context of integrated watershed modeling and management. PMID:25837571

  4. Environmental and biotechnological applications of high-voltage pulsed discharges in water

    NASA Astrophysics Data System (ADS)

    Sato, Masayuki

    2008-05-01

    A high-voltage pulse has wide application in fields such as chemistry, physics and biology and their combinations. The high-voltage pulse forms two kinds of physical processes in water, namely (a) a pulsed electric field (PEF) in the parallel electrode configuration and (b) plasma generation by a pulsed discharge in the water phase with a concentrated electric field. The PEF can be used for inactivation of bacteria in liquid foods as a non-thermal process, and the underwater plasma is applicable not only for the decomposition of organic materials in water but also for biological treatment of wastewater. These discharge states are controlled mainly by the applied pulse voltage and the electrode shape. Some examples of environmental and biotechnological applications of a high-voltage pulse are reviewed.

  5. High-Resolution Glacial Discharge Records From Deep-Water Tidal Rhythmites in an Alaskan Fjord

    NASA Astrophysics Data System (ADS)

    Jackolski, C. L.; Cowan, E. A.; Jaeger, J. M.; Powell, R. D.

    2006-12-01

    In this study we have compiled and analyzed two high-resolution records of deep-water tidal rhythmites derived from glacial discharges. The rhythmites contain an average of 1 cm of sediment thickness per week during the melt-season. Two sediment cores over 17-m-long were collected from Muir Inlet, Glacier Bay National Park, Southeast Alaska, aboard the R/V Maurice Ewing in 2004 (EW0408). One core (core 60JC) was collected just north of the mouth of Wachusett Inlet. The other (core 62JC) was collected 3.8 km due north of 60JC in a separate basin more proximal to Muir and McBride Glaciers. In Glacier Bay, glacial retreat since the Little Ice Age Maximum is well constrained by historical mapping of glacial temini, and local climate records exist as well. The next step after establishing glacial discharge records is to test hypotheses relating glacial discharge to temperature and rainfall. The cores were subsampled with ODP-style u-channels and scanned for magnetic susceptibility and bulk density. X-radiographs of u-channels were collected to observe small-scale (42 microns/pixel) density differences between silt and mud laminae. Spring-neap tidal packages, representing 2-week periods during summer, are visible because of closely-spaced bounding silt laminae. Seasonality is marked by winter gravelly mud (diamicton) beds and/or spring plankton blooms. Spring-neap packages and seasonal markers were considered jointly in order to construct two mostly continuous records of spring-neap packages and melt- season deposits in each core. Secondarily, melt-season duration, which we define as the number of spring- neap packages occurring in a melt-season, was determined. We found that core 60JC extends back 83 years. 75 of those years were identified as having complete, contiguous melt-season deposits that are, on average, 17 cm thick and contain 8.3 spring-neap packages. Core 62JC extends back 62 years. 57 of those years were identified as having complete, contiguous melt

  6. Impacts of a high-discharge submarine sewage outfall on water quality in the coastal zone of Salvador (Bahia, Brazil).

    PubMed

    Roth, F; Lessa, G C; Wild, C; Kikuchi, R K P; Naumann, M S

    2016-05-15

    Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine sewage outfall close to Salvador, Brazil. Impacts of untreated sewage discharge were evident at the outfall site by depleted δ(13)Corg and δ(15)N signatures and 4-fold increased BOD rates. Pollution effects of a sewage plume were detectable for more than 6km downstream from the outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality. PMID:27038882

  7. Single-step process for the deposition of high water contact angle and high water sliding angle surfaces by atmospheric pressure dielectric barrier discharge.

    PubMed

    Boscher, Nicolas D; Duday, David; Verdier, Stéphane; Choquet, Patrick

    2013-02-01

    Fluorine-free surfaces with high water contact angle (WCA) and high adhesion force to water are prepared by the atmospheric pressure dielectric barrier discharge (AP-DBD) of hexamethyldisiloxane on cold rolled aluminum foil. Water droplets, which remained on the plasma-polymerized hexamethyldisiloxane (ppHMDSO) surface with contact angle of 155°, do not slide even when the surface is tilted vertically or turned upside down. Scanning electron microscopy, atomic force microscopy and confocal microscopy highlight the importance of the dual-scale roughness of the ppHMDSO surface. The "sticky" high WCA property is achieved only when the nanometer scale particles generated during the AP-DBD process are present at the surface of the film and combine to the micrometer scale rolling lines of the aluminum substrate. PMID:23339545

  8. Water purification by electrical discharges

    NASA Astrophysics Data System (ADS)

    Arif Malik, Muhammad; Ghaffar, Abdul; Akbar Malik, Salman

    2001-02-01

    There is a continuing need for the development of effective, cheap and environmentally friendly processes for the disinfection and degradation of organic pollutants from water. Ozonation processes are now replacing conventional chlorination processes because ozone is a stronger oxidizing agent and a more effective disinfectant without any side effects. However, the fact that the cost of ozonation processes is higher than chlorination processes is their main disadvantage. In this paper recent developments targeted to make ozonation processes cheaper by improving the efficiency of ozone generation, for example, by incorporation of catalytic packing in the ozone generator, better dispersion of ozone in water and faster conversion of dissolved ozone to free radicals are described. The synthesis of ozone in electrical discharges is discussed. Furthermore, the generation and plasma chemical reactions of several chemically active species, such as H2O2, Obullet, OHbullet, HO2bullet, O3*, N2*, e-, O2-, O-, O2+, etc, which are produced in the electrical discharges are described. Most of these species are stronger oxidizers than ozone. Therefore, water treatment by direct electrical discharges may provide a means to utilize these species in addition to ozone. Much research and development activity has been devoted to achieve these targets in the recent past. An overview of these techniques and important developments that have taken place in this area are discussed. In particular, pulsed corona discharge, dielectric barrier discharge and contact glow discharge electrolysis techniques are being studied for the purpose of cleaning water. The units based on electrical discharges in water or close to the water level are being tested at industrial-scale water treatment plants.}

  9. START High Performance Discharges

    NASA Astrophysics Data System (ADS)

    Gates, D. A.

    1997-11-01

    Improvements to START (Small Tight Aspect Ratio Tokamak), the first spherical tokamak in the world to achieve high plasma temperature with both a significant pulse length and confinement time, have been ongoing since 1991. Recent modifications include: expansion of the existing capacitor banks allowing plasma currents as high as 300kA, an increase in the available neutral beam heating power ( ~ 500kW), and improvements to the vacuum system. These improvements have led to the achievement of the world record plasma β (≡ 2μ_0 /B^2) of ~ 30% in a tokamak. The normalised β ( βN ≡ β aB/I_p) reached 4.5 with q_95 = 2.3. Properties of the reconstructed equilibrium will be discussed in detail. The theoretical limit to β is higher in a spherical tokamak than in a conventional machine, due to the higher values of normalised current (IN ≡ I_p/aB) achievable at low aspect ratio. The record β was achieved with IN ~ 8 while conventional tokamaks are limited to IN ~ 3, or less. Calculations of the ideal MHD stability of the record discharge indicate high β low-n kink modes are stable, but that the entire profile is at or near marginal stability for high-n ballooning modes. The phenomenology of the events leading up to the plasma termination is discussed. An important aspect of the START program is to explore the physics of neutral beam absorption at low aspect ratio. A passive neutral particle analyser has been used to study the temporal and spatial dependence of the fast hydrogen beam ions. These measurements have been used in conjunction with a single particle orbit code to estimate the fast ion losses due to collisions with slow neutrals from the plasma edge. Numerical analysis of neutral beam power deposition profiles are compared with the data from an instrumented beam stop. The global energy confinement time τE in beam heated discharges on START is similar to that obtained in Ohmic discharges, even though the input power has roughly doubled over the Ohmic case

  10. Discharge and water chemistry of High Arctic rivers in NW Greenland (76° N, 68° W)

    NASA Astrophysics Data System (ADS)

    Hagedorn, B.; Sletten, R. S.; Vigna, A. C.; Hallet, B.

    2004-12-01

    The volume, temperature, and quality of freshwater runoff from high latitude areas ultimately affect sensitive components of polar oceans, including water stratification, nutrient cycling, and formation of deepwater currents. Freshwater is conveyed from Greenland to the ocean from a multitude of medium-sized rivers for which little is known about discharge and water characteristics. River runoff together with microclimate and soil processes were recorded in a typical high Arctic area in NW Greenland where complete climate records from pre-1978 to the present indicate increases in mean annual air temperature from -12.0° C to -10.7° C and precipitation from 65 mm to 120 mm water equivalent between 1993 and 2002. The study will improve understanding of the interaction between climate, landscape processes, and river runoff. The study site extends from the western edge of the Greenland Ice Sheet to Baffin Bay; it covers an area ranging between 10-20 km E-W and 10-15 km N-S, and the elevations reach 700 m. It is a typical high Arctic environment with sparse vegetation and pervasive active patterned ground. Most of the area is covered by glacial drift that resembles the underlying sedimentary and igneous Archean and Proterozoic bedrock. To address how seasonal weather patterns and landscape processes affect runoff and water quality, as well as to examine weathering and carbon budgets in the drainage, we monitor water discharge and suspended load, water temperature, water chemistry (pH, dissolved ions, dissolved organic and inorganic carbon) of three rivers. Two of these rivers originate as melt water runoff from the Greenland Ice Sheet. The third stream is fed by local snowmelt and summer rain events. In addition, climate data along with soil moisture and temperature are recorded with automated stations at two locations. The potential sources of river water are thawing permafrost, local snowmelt, rain, and melting of glacial ice that all have distinct isotopic

  11. Discharges in Water and Applications to Wasted Water Treatment

    NASA Astrophysics Data System (ADS)

    Yamabe, Chobei; Yamashita, Takanori; Ihara, Satoshi

    Recently the electrical discharge in water has been used for the water treatment. In this study, various shape of electrodes were examined to observe and measure the electrical discharge phenomena in water. Both the Marx generator and the pulsed power generator were used to generate the discharge in water. The oscillation on the waveforms of both applied voltage and discharge current was observed using the pulsed power generator whose peak applied voltage was about 80-120 kV and its discharge repetition rate was about one pulse per thirty seconds although it wasn't observed on the waveforms in the practical use of the high voltage generator (peak applied voltage was about 30-40 kV) with high repetition rate of discharge (20-300 pulses per second). Bubbles were introduced into the discharge region of main electrode using the ejector and the generation of hydroxyl radicals (OH) was confirmed by the measurement of emission spectrum of discharge in water and the intensity of OH radicals increased with the ratio of G/L (where, G is gas flow rate and L is water flow rate). The hydrogen peroxide (H2O2) was also measured and this reactor system was applied for the de-color of water.

  12. Estimating ground water discharge by hydrograph separation.

    PubMed

    Hannula, Steven R; Esposito, Kenneth J; Chermak, John A; Runnells, Donald D; Keith, David C; Hall, Larry E

    2003-01-01

    Iron Mountain is located in the West Shasta Mining District in California. An investigation of the generation of acid rock drainage and metals loading to Boulder Creek at Iron Mountain was conducted. As part of that investigation, a hydrograph separation technique was used to determine the contribution of ground water to total flow in Boulder Creek. During high-flow storm events in the winter months, peak flow in Boulder Creek can exceed 22.7 m3/sec, and comprises surface runoff, interflow, and ground water discharge. A hydrograph separation technique was used to estimate ground water discharge into Boulder Creek during high-flow conditions. Total ground water discharge to the creek approaches 0.31 m3/sec during the high-flow season. The hydrograph separation technique combined with an extensive field data set provided reasonable estimates of ground water discharge. These estimates are useful for other investigations, such as determining a corresponding metals load from the metal-rich ground water found at Iron Mountain and thus contributing to remedial alternatives. PMID:12772830

  13. Stretched arc discharge in produced water.

    PubMed

    Cho, Y I; Wright, K C; Kim, H S; Cho, D J; Rabinovich, A; Fridman, A

    2015-01-01

    The objective of the present study was to investigate the feasibility of stretching an arc discharge in produced water to increase the volume of produced water treated by plasma. Produced water is the wastewater generated by hydraulic fracturing of shale during the production phase in shale-oil or shale-gas exploration. The electric conductivity of produced water is in the range of 50-200 mS/cm, which provides both a challenge and opportunity for the application of plasmas. Stretching of an arc discharge in produced water was accomplished using a ground electrode and two high-voltage electrodes: one positioned close to the ground electrode and the other positioned farther away from the ground. The benefit of stretching the arc is that the contact between the arc and water is significantly increased, resulting in more efficient plasma treatment in both performance and energy cost. PMID:25638080

  14. Stretched arc discharge in produced water

    NASA Astrophysics Data System (ADS)

    Cho, Y. I.; Wright, K. C.; Kim, H. S.; Cho, D. J.; Rabinovich, A.; Fridman, A.

    2015-01-01

    The objective of the present study was to investigate the feasibility of stretching an arc discharge in produced water to increase the volume of produced water treated by plasma. Produced water is the wastewater generated by hydraulic fracturing of shale during the production phase in shale-oil or shale-gas exploration. The electric conductivity of produced water is in the range of 50-200 mS/cm, which provides both a challenge and opportunity for the application of plasmas. Stretching of an arc discharge in produced water was accomplished using a ground electrode and two high-voltage electrodes: one positioned close to the ground electrode and the other positioned farther away from the ground. The benefit of stretching the arc is that the contact between the arc and water is significantly increased, resulting in more efficient plasma treatment in both performance and energy cost.

  15. High-resolution water column survey to identify active sublacustrine hydrothermal discharge zones within Lake Rotomahana, North Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Walker, Sharon L.; de Ronde, Cornel E. J.; Fornari, Daniel; Tivey, Maurice A.; Stucker, Valerie K.

    2016-03-01

    Autonomous underwater vehicles were used to conduct a high-resolution water column survey of Lake Rotomahana using temperature, pH, turbidity, and oxidation-reduction potential (ORP) to identify active hydrothermal discharge zones within the lake. Five areas with active sublacustrine venting were identified: (1) the area of the historic Pink Terraces; (2) adjacent to the western shoreline subaerial "Steaming Cliffs," boiling springs and geyser; (3) along the northern shoreline to the east of the Pink Terrace site; (4) the newly discovered Patiti hydrothermal system along the south margin of the 1886 Tarawera eruption rift zone; and (5) a location in the east basin (northeast of Patiti Island). The Pink Terrace hydrothermal system was active prior to the 1886 eruption of Mount Tarawera, but venting along the western shoreline, in the east basin, and the Patiti hydrothermal system appear to have been initiated in the aftermath of the eruption, similar to Waimangu Valley to the southwest. Different combinations of turbidity, pH anomalies (both positive and negative), and ORP responses suggest vent fluid compositions vary over short distances within the lake. The seasonal period of stratification limits vertical transport of heat to the surface layer and the hypolimnion temperature of Lake Rotomahana consequently increases with an average warming rate of ~ 0.010 °C/day due to both convective hydrothermal discharge and conductive geothermal heating. A sudden temperature increase occurred during our 2011 survey and was likely the response to an earthquake swarm just 11 days prior.

  16. Surface water discharges from onshore stripper wells.

    SciTech Connect

    Veil, J. A.

    1998-01-16

    Under current US Environmental Protection Agency (EPA) rules, small onshore oil producers are allowed to discharge produced water to surface waters with approval from state agencies; but small onshore gas producers, however, are prohibited from discharging produced water to surface waters. The purpose of this report is to identify those states that allow surface water discharges from small onshore oil operations and to summarize the types of permitting controls they use. It is intended that the findings of this report will serve as a rationale to encourage the EPA to revise its rules and to remove the prohibition on surface water discharges from small gas operations.

  17. Non-storm water discharges technical report

    SciTech Connect

    Mathews, S.

    1994-07-01

    Lawrence Livermore National Laboratory (LLNL) submitted a Notice of Intent to the California State Water Resources Control Board (hereafter State Board) to discharge storm water associated with industrial activities under the California General Industrial Activity Storm Water National Pollutant Elimination System Discharge Permit (hereafter General Permit). As required by the General Permit, LLNL provided initial notification of non-storm water discharges to the Central Valley Regional Water Quality Control Board (hereafter Regional Board) on October 2, 1992. Additional findings and progress towards corrective actions were reported in subsequent annual monitoring reports. LLNL was granted until March 27, 1995, three years from the Notice of Intent submission date, to eliminate or permit the non-storm water discharges. On May 20, 1994, the Regional Board issued Waste Discharge Requirements (WDR Board Order No. 94-131, NPDES No. CA0081396) to LLNL for discharges of non-contact cooling tower wastewater and storm water related to industrial activities. As a result of the issuance of WDR 94-131, LLNL rescinded its coverage under the General Permit. WDR 94-131 allowed continued non-storm water discharges and requested a technical report describing the discharges LLNL seeks to permit. For the described discharges, LLNL anticipates the Regional Board will either waive Waste Discharge Requirements as allowed for in The Water Quality Control Plan for the California Regional Water Quality Control Board, Central Valley Region (hereafter Basin Plan) or amend Board Order 94-131 as appropriate.

  18. Effect of fine bubbles on electric discharge in water

    NASA Astrophysics Data System (ADS)

    Hayashi, Yui; Takada, Noriharu; Kanda, Hideki; Goto, Motonobu

    2015-10-01

    Ar or O2 fine bubbles of diameter  <80 μm were introduced in water and a pulsed discharge plasma was generated between cylinder electrodes in water. Fine bubbles in water affected discharge ignition and caused low inception voltage and suppression of rising temperature. The contamination from electrodes was suppressed in the case of fine bubbles addition because fine bubbles assisted plasma generation. In addition, discharge with fine bubbles enhanced plasma emission with high electron density compared to the no-bubbling case. Discharge with fine bubbles at low-pH conditions generated intense plasma emission compared to neutral and high-pH conditions owing to the electric charge of the fine bubbles.

  19. Properties of water surface discharge at different pulse repetition rates

    NASA Astrophysics Data System (ADS)

    Ruma, Hosseini, S. H. R.; Yoshihara, K.; Akiyama, M.; Sakugawa, T.; Lukeš, P.; Akiyama, H.

    2014-09-01

    The properties of water surface discharge plasma for variety of pulse repetition rates are investigated. A magnetic pulse compression (MPC) pulsed power modulator able to deliver pulse repetition rates up to 1000 Hz, with 0.5 J per pulse energy output at 25 kV, was used as the pulsed power source. Positive pulse with a point-to-plane electrode configuration was used for the experiments. The concentration and production yield of hydrogen peroxide (H2O2) were quantitatively measured and orange II organic dye was treated, to evaluate the chemical properties of the discharge reactor. Experimental results show that the physical and chemical properties of water surface discharge are not influenced by pulse repetition rate, very different from those observed for under water discharge. The production yield of H2O2 and degradation rate per pulse of the dye did not significantly vary at different pulse repetition rates under a constant discharge mode on water surface. In addition, the solution temperature, pH, and conductivity for both water surface and underwater discharge reactors were measured to compare their plasma properties for different pulse repetition rates. The results confirm that surface discharge can be employed at high pulse repetition rates as a reliable and advantageous method for industrial and environmental decontamination applications.

  20. Properties of water surface discharge at different pulse repetition rates

    SciTech Connect

    Ruma,; Yoshihara, K.; Hosseini, S. H. R. Sakugawa, T.; Akiyama, H.; Akiyama, M.; Lukeš, P.

    2014-09-28

    The properties of water surface discharge plasma for variety of pulse repetition rates are investigated. A magnetic pulse compression (MPC) pulsed power modulator able to deliver pulse repetition rates up to 1000 Hz, with 0.5 J per pulse energy output at 25 kV, was used as the pulsed power source. Positive pulse with a point-to-plane electrode configuration was used for the experiments. The concentration and production yield of hydrogen peroxide (H₂O₂) were quantitatively measured and orange II organic dye was treated, to evaluate the chemical properties of the discharge reactor. Experimental results show that the physical and chemical properties of water surface discharge are not influenced by pulse repetition rate, very different from those observed for under water discharge. The production yield of H₂O₂ and degradation rate per pulse of the dye did not significantly vary at different pulse repetition rates under a constant discharge mode on water surface. In addition, the solution temperature, pH, and conductivity for both water surface and underwater discharge reactors were measured to compare their plasma properties for different pulse repetition rates. The results confirm that surface discharge can be employed at high pulse repetition rates as a reliable and advantageous method for industrial and environmental decontamination applications.

  1. Breakdown and dc discharge in low-pressure water vapour

    NASA Astrophysics Data System (ADS)

    Sivoš, J.; Škoro, N.; Marić, D.; Malović, G.; Petrović, Z. Lj

    2015-10-01

    In this paper we report studies of basic properties of breakdown, low-current Townsend discharge and high-current discharge regimes in water vapour. Paschen curves and the corresponding distributions of emission intensities at low current were recorded in the range of pd (pressure x electrode gap) from 0.1 to 10 Torrcm covering the region of Paschen minimum. From the experimental profiles we obtained effective ionization coefficient of water vapour for the E/N range 650 Td-7 kTd and fitted the results by using the extended Townsend analytical formula. Using the obtained ionization coefficient, we calculated the effective yield of secondary electrons from the copper cathode. Results of the measurements of Volt-Ampere characteristics in water vapour were presented together with the images of the axial structure of the discharge in a wide range of discharge currents for two pd values. Recorded profiles showed development of the spatial structure of the discharge in different operating regimes. We were able to identify conditions where processes induced by heavy particles, probably fast hydrogen atoms, are dominant in inducing emission from the discharge. Finally, standard scaling laws were tested for low current and glow discharges in water vapour.

  2. State waste discharge permit application for cooling water and condensate discharges

    SciTech Connect

    Haggard, R.D.

    1996-08-12

    The following presents the Categorical State Waste Discharge Permit (SWDP) Application for the Cooling Water and Condensate Discharges on the Hanford Site. This application is intended to cover existing cooling water and condensate discharges as well as similar future discharges meeting the criteria set forth in this document.

  3. Optical Emission Spectroscopy of Microplasma Discharge in Sea Water

    NASA Astrophysics Data System (ADS)

    Gamaleev, Vladislav; Hatta, Akimitsu; Furuta, Hiroshi; Oh, Jun-Seok; Okamura, Yo; Kitamura, Kensuke; Hashimoto, Yusuke

    2015-09-01

    We have been investigating microplasma discharge in sea water for optical emission spectroscopy. Microplasma discharge in artificial sea water (10ASW) was carried using needle-to-plane platinum electrode system. The gap, between electrodes, was ranged from 10 to 60 microns. The electricity source was impulse generatorwith MOSFET switch and variable capacitance and inductance. The maximum voltage and current for this scheme were respectively 1 kV and 10 A, pulse width 10 μs. It has been confirmed that, using the micro-gap configuration, spark discharges were ignited at the conventional breakdown voltages below 1kV, even in the conductive sea water. Was noted formation of small bubbles before of the plasma ignition process. The mechanism of formation of these bubbles is mostly Joule heating because of high currents. It has been speculated that plasma discharge initiates in bubbles. Optical emission spectroscopy of microplasma in sea water was carried. In the spectra, emission peaks for H, O, Na, Mg, Ca, Cl and Pt were clearly detected. Besides the main components of 10ASW, contaminants from the electrodes appeared in the spectra. The characteristics of microplasma discharge in sea water and analysis of the optical emission spectra will be presented. This work was supported by JSPS KAKENHI Grant Number 26600129. The ASW was provided from Prof. Kei Okamura of Kochi University.

  4. Diagnostics of High-Intensity-Discharges

    NASA Astrophysics Data System (ADS)

    Adler, Helmar G.

    1996-05-01

    High intensity light sources have come a long way since the introduction of high pressure discharges in mercury and later in sodium. The introduction of other species (e.g. metal halides) into the discharge chemistry led to marked improvements in light intensity (lumens per watt or LPW) and the appearance of the light output (color rendering index or CRI). Many of these improvements have been achieved through qualitative understanding of the discharge and good engineering. The accurate predictions of discharge behavior and spectral power distribution through HID-models remains a difficult and challenging goal for lighting scientists. Modelling of a real lamp is complicated due to the high pressures in the discharge, the geometric influences of the discharge vessel, and the interactions between fills, wall materials and electrodes. The simultaneous use of solid-, liquid-, gaseous- and plasma-state descriptions, including for example effects of radiation transport, becomes necessary. Spectroscopic measurements have been and are still of highest value, not only to determine practical parameters like LPW and CRI, but also to determine species distributions and temperatures, eventually as a function of location in the discharge and time. These measurements are necessary not only for the quantitative understanding of the discharge mechanisms, but also to serve as a testbed for all simulation efforts. This paper will focus on diagnostic possibilities and opportunities using imaging data acquisition systems.

  5. High power impulse magnetron sputtering discharge

    SciTech Connect

    Gudmundsson, J. T.; Brenning, N.; Lundin, D.; Helmersson, U.

    2012-05-15

    The high power impulse magnetron sputtering (HiPIMS) discharge is a recent addition to plasma based sputtering technology. In HiPIMS, high power is applied to the magnetron target in unipolar pulses at low duty cycle and low repetition frequency while keeping the average power about 2 orders of magnitude lower than the peak power. This results in a high plasma density, and high ionization fraction of the sputtered vapor, which allows better control of the film growth by controlling the energy and direction of the deposition species. This is a significant advantage over conventional dc magnetron sputtering where the sputtered vapor consists mainly of neutral species. The HiPIMS discharge is now an established ionized physical vapor deposition technique, which is easily scalable and has been successfully introduced into various industrial applications. The authors give an overview of the development of the HiPIMS discharge, and the underlying mechanisms that dictate the discharge properties. First, an introduction to the magnetron sputtering discharge and its various configurations and modifications is given. Then the development and properties of the high power pulsed power supply are discussed, followed by an overview of the measured plasma parameters in the HiPIMS discharge, the electron energy and density, the ion energy, ion flux and plasma composition, and a discussion on the deposition rate. Finally, some of the models that have been developed to gain understanding of the discharge processes are reviewed, including the phenomenological material pathway model, and the ionization region model.

  6. Problems associated with estimating ground water discharge and recharge from stream-discharge records

    USGS Publications Warehouse

    Halford, K.J.; Mayer, G.C.

    2000-01-01

    Ground water discharge and recharge frequently have been estimated with hydrograph-separation techniques, but the critical assumptions of the techniques have not been investigated. The critical assumptions are that the hydraulic characteristics of the contributing aquifer (recession index) can be estimated from stream-discharge records; that periods of exclusively ground water discharge can be reliably identified; and that stream-discharge peaks approximate the magnitude and tinting of recharge events. The first assumption was tested by estimating the recession index from st earn-discharge hydrographs, ground water hydrographs, and hydraulic diffusivity estimates from aquifer tests in basins throughout the eastern United States and Montana. The recession index frequently could not be estimated reliably from stream-discharge records alone because many of the estimates of the recession index were greater than 1000 days. The ratio of stream discharge during baseflow periods was two to 36 times greater than the maximum expected range of ground water discharge at 12 of the 13 field sites. The identification of the ground water component of stream-discharge records was ambiguous because drainage from bank-storage, wetlands, surface water bodies, soils, and snowpacks frequently exceeded ground water discharge and also decreased exponentially during recession periods. The timing and magnitude of recharge events could not be ascertained from stream-discharge records at any of the sites investigated because recharge events were not directly correlated with stream peaks. When used alone, the recession-curve-displacement method and other hydrograph-separation techniques are poor tools for estimating ground water discharge or recharge because the major assumptions of the methods are commonly and grossly violated. Multiple, alternative methods of estimating ground water discharge and recharge should be used because of the uncertainty associated with any one technique.

  7. Water quality impacts of stormwater discharges to Santa Monica Bay.

    PubMed

    Bay, Steven; Jones, Burton H; Schiff, Kenneth; Washburn, Libe

    2003-01-01

    Urban stormwater runoff is a major source of contaminants to southern California's coastal waters, yet little is known about the fate and effects of these discharges. A 3-year multidisciplinary project was conducted to investigate the dispersion of stormwater plumes in Santa Monica Bay and the resultant impacts on the water column and benthos. This paper describes the toxicity component of the study. Sea urchin fertilization toxicity tests were conducted on stormwater from the two largest discharges into the bay: Ballona Creek, which drains a highly urbanized watershed, and Malibu Creek, which receives runoff from a largely undeveloped watershed. Every sample of Ballona Creek stormwater tested was toxic (usually >5 toxic units), while Malibu Creek stormwater had a lower frequency and magnitude of toxicity (usually <4 toxic units). Surface water samples collected within the Ballona Creek stormwater discharge plume were always toxic whenever the concentration of stormwater in the plume exceeded 10%. The toxic portion of the Ballona Creek stormwater plume extended more than 4 km offshore on one occasion. Toxicity identification studies indicated that zinc was the primary cause of toxicity in both Ballona Creek stormwater and the discharge plume. No acute sediment toxicity (10-day amphipod survival) was present in the study area, although interstitial water toxicity was present at some stations located near the mouth of Ballona Creek. Differences in watershed characteristics likely were responsible for the greater toxicity of the Ballona Creek stormwater discharge plume. The Ballona Creek watershed contained a greater degree of urbanization (83% versus 12% for Malibu Creek) and the presence of a network of concrete flood control channels resulted in a stormwater plume containing elevated concentrations of toxins that received less initial dilution (compared to Malibu Creek) in the nearshore environment. PMID:12648956

  8. High Power ECR Ion Thruster Discharge Characterization

    NASA Technical Reports Server (NTRS)

    Foster, John E.; Kamhawi, Hani; Haag, Thomas; Carpenter, Christian; Williams, George W.

    2006-01-01

    Electron cyclotron resonance (ECR) based ion thrusters with carbon based ion optics can potentially satisfy lifetime requirements for long duration missions (approximately 10 years) because grid erosion and cathode insert depletion issues are virtually eliminated. Though the ECR plasma discharge has been found to typically operate at slightly higher discharge losses than conventional DC ion thrusters (for high total thruster power applications), the discharge power fraction is small (less than 1 percent at 25 kW). In this regard, the benefits of increased life, low discharge plasma potentials, and reduced complexity are welcome tradeoffs for the associated discharge efficiency decrease. Presented here are results from discharge characterization of a large area ECR plasma source for gridded ion thruster applications. These measurements included load matching efficacy, bulk plasma properties via Langmuir probe, and plasma uniformity as measured using current probes distributed at the exit plane. A high degree of plasma uniformity was observed (flatness greater than 0.9). Additionally, charge state composition was qualitatively evaluated using emission spectroscopy. Plasma induced emission was dominated by xenon ion lines. No doubly charged xenon ions were detected.

  9. Fine-Water-Mist Multiple-Orientation-Discharge Fire Extinguisher

    NASA Technical Reports Server (NTRS)

    Butz, James R.; Turchi, Craig S.; Kimball, Amanda; McKinnon, Thomas; Riedel, Edward

    2010-01-01

    A fine-water-mist fire-suppression device has been designed so that it can be discharged uniformly in any orientation via a high-pressure gas propellant. Standard fire extinguishers used while slightly tilted or on their side will not discharge all of their contents. Thanks to the new design, this extinguisher can be used in multiple environments such as aboard low-gravity spacecraft, airplanes, and aboard vehicles that may become overturned prior to or during a fire emergency. Research in recent years has shown that fine water mist can be an effective alternative to Halons now banned from manufacture. Currently, NASA uses carbon dioxide for fire suppression on the International Space Station (ISS) and Halon chemical extinguishers on the space shuttle. While each of these agents is effective, they have drawbacks. The toxicity of carbon dioxide requires that the crew don breathing apparatus when the extinguishers are deployed on the ISS, and Halon use in future spacecraft has been eliminated because of international protocols on substances that destroy atmospheric ozone. A major advantage to the new system on occupied spacecraft is that the discharged system is locally rechargeable. Since the only fluids used are water and nitrogen, the system can be recharged from stores of both carried aboard the ISS or spacecraft. The only support requirement would be a pump to fill the water and a compressor to pressurize the nitrogen propellant gas. This system uses a gaseous agent to pressurize the storage container as well as to assist in the generation of the fine water mist. The portable fire extinguisher hardware works like a standard fire extinguisher with a single storage container for the agents (water and nitrogen), a control valve assembly for manual actuation, and a discharge nozzle. The design implemented in the proof-of-concept experiment successfully extinguished both open fires and fires in baffled enclosures.

  10. Biotoxicity characterization of a produced-water discharge in Wyoming

    SciTech Connect

    Mancini, E.R.; Stilwell, C.T. )

    1992-06-01

    The objectives of this paper are to document the physicochemical and aquatic toxicological quality of a beneficial-use produced-water discharge and its effect on a receiving stream in Wyoming. Fish and water-flea survival, growth, and reproduction tests indicated that the discharge and all other sampling stations passed the state effluent biomonitoring acute toxicity testing endpoints. while benthic macroinvertebrates were absent at the discharge point designated by the Natl. Pollutant Discharge Elimination System (NPDES), productive and reproducing populations were present at all other downstream and mixing-zone stations. This investigation confirmed the validity of the beneficial-use subcategory for this oilfield discharge.

  11. Approaches to setting organism-based ballast water discharge standards

    EPA Science Inventory

    As a major vector by which foreign species invade coastal and freshwater waterbodies, ballast water discharge from ships is recognized as a major environmental threat. The International Maritime Organization (IMO) drafted an international ballast water treaty establishing ballast...

  12. Statistical considerations in estimating organism concentrations in ballast water discharges

    EPA Science Inventory

    Sampling probabilities may affect the practical use of different ballast water performance standards which establish the acceptable concentration of organisms in ballast discharges. The International Maritime Organization (IMO) has initiated a ballast water standard of <10 viabl...

  13. Advanced high frequency partial discharge measuring system

    NASA Technical Reports Server (NTRS)

    Karady, George G.

    1994-01-01

    This report explains the Advanced Partial Discharge Measuring System in ASU's High Voltage Laboratory and presents some of the results obtained using the setup. While in operation an insulation is subjected to wide ranging temperature and voltage stresses. Hence, it is necessary to study the effect of temperature on the behavior of partial discharges in an insulation. The setup described in this report can be used to test samples at temperatures ranging from -50 C to 200 C. The aim of conducting the tests described herein is to be able to predict the behavior of an insulation under different operating conditions in addition to being able to predict the possibility of failure.

  14. Discharge indices for water quality loads

    USGS Publications Warehouse

    Vogel, R.M.; Stedinger, J.R.; Hooper, R.P.

    2003-01-01

    Effective discharge has been used to describe the streamflow level that is responsible for transporting the most sediment over the long term. Careful inspection reveals that this concept may not have been well defined, and different interpretations have led to conflicting representations. Because total load is ultimately the quantity of interest, we define a new index, the half-load discharge, which is that discharge above and below which half the total long-term load is transported. The value of the half-load discharge is derived for a reasonable model of flows and constituent concentration. The effective discharge has generally been thought to be a relatively common or frequent flood. The half-load discharge is generally a much greater and less frequent flow than commonly used estimators of the effective discharge. Relations provided here for the frequency and magnitude of the half-load discharge provide evidence that it is relatively rare floods that transport most of the sediment over the long term. These ideas apply to other constituents as well.

  15. Warm Atlantic water drives Greenland Ice Sheet discharge dynamics

    NASA Astrophysics Data System (ADS)

    Christoffersen, P.; Heywood, K. J.; Dowdeswell, J. A.; Syvitski, J. P.; Benham, T. J.; Mugford, R. I.; Joughin, I.; Luckman, A.

    2008-12-01

    Greenland outlet glaciers terminating in fjords experience seasonal fluctuations as well as abrupt episodes of rapid retreat and speed-up. The cause of abrupt speed-up events is not firmly established, but synchronous occurrences suggest that it is related to Arctic warming. Here, we report major warming of water masses in Kangerdlugssuaq Fjord, East Greenland, immediately prior to the fast retreat and speed-up of Kangerdlugssuaq Glacier in 2004-05. Our hydrographic data show that this event occurred when Atlantic water entered the fjord and increased temperature of surface water by 4°C and deep water by 1°C. On the basis of meteorological records and satellite-derived sea surface temperatures, which fluctuate by up to 4°C in periods of 2-3 years, we infer that inflow of Atlantic water is controlled by the direction and intensity of prevailing winds that force coastal and offshore currents. Our results demonstrate that Greenland Ice Sheet discharge dynamics are modulated by North Atlantic climate variability, which is identified by shifts in the position of atmospheric low pressure over the Labrador and Irminger seas. A persisting westerly position of the Icelandic Low since 1999 may explain why winters in Greenland have been particularly mild during the last decade and it is feasible that widespread and synchronous discharge fluctuations from outlet glaciers, which resulted in high rates of ice loss in southeast Greenland, are a consequence of this synoptic condition.

  16. High intensity discharge device containing oxytrihalides

    DOEpatents

    Lapatovich, W.P.; Keeffe, W.M.; Liebermann, R.W.; Maya, J.

    1987-06-09

    A fill composition for a high intensity discharge device including mercury, niobium oxytrihalide, and a molecular stabilization agent is provided. The molar ratio of niobium oxytrihalide to the molecular stabilization agent in the fill is in the range of from about 5:1 to about 7.5:1. Niobium oxytrihalide is present in the fill in sufficient amount to produce, by dissociation in the discharge, atomic niobium, niobium oxide, NbO, and niobium dioxide, NbO[sub 2], with the molar ratio of niobium-containing vapor species to mercury in the fill being in the range of from about 0.01:1 to about 0.50:1; and mercury pressure of about 1 to about 50 atmospheres at lamp operating temperature. There is also provided a high intensity discharge device comprising a sealed light-transmissive arc tube; the arc tube including the above-described fill; and an energizing means for producing an electric discharge within the arc tube. 7 figs.

  17. High intensity discharge device containing oxytrihalides

    DOEpatents

    Lapatovich, Walter P.; Keeffe, William M.; Liebermann, Richard W.; Maya, Jakob

    1987-01-01

    A fill composition for a high intensity discharge device including mercury, niobium oxytrihalide, and a molecular stabilization agent is provided. The molar ratio of niobium oxytrihalide to the molecular stabilization agent in the fill is in the range of from about 5:1 to about 7.5:1. Niobium oxytrihalide is present in the fill in sufficient amount to produce, by dissociation in the discharge, atomic niobium, niobium oxide, NbO, and niobium dioxide, NbO.sub.2, with the molar ratio of niobium-containing vapor species to mercury in the fill being in the range of from about 0.01:1 to about 0.50:1; and mercury pressure of about 1 to about 50 atmospheres at lamp operating temperature. There is also provided a high intensity discharge device comprising a sealed light-transmissive arc tube; the arc tube including the above-described fill; and an energizing means for producing an electric discharge within the arc tube.

  18. DC diaphragm discharge in water solutions of selected organic acids

    NASA Astrophysics Data System (ADS)

    Vyhnankova, Edita J.; Hammer, Malte U.; Reuter, Stephan; Krcma, Frantisek

    2015-07-01

    Effect of four simple organic acids water solution on a DC diaphragm discharge was studied. Efficiency of the discharge was quantified by the hydrogen peroxide production determined by UV-VIS spectrometry of a H2O2 complex formed with specific titanium reagent. Automatic titration was used to study the pH behaviour after the plasma treatment. Optical emission spectroscopy overview spectra were recorded and detailed spectra of OH band and Hβ line were used to calculate the rotational temperature and comparison of the line profile (reflecting electron concentration) in the acid solutions. Contribution to the topical issue "The 14th International Symposium on High Pressure Low Temperature Plasma Chemistry (HAKONE XIV)", edited by Nicolas Gherardi, Ronny Brandenburg and Lars Stollenwark

  19. Enhanced submarine ground water discharge form mixing of pore water and estuarine water

    USGS Publications Warehouse

    Martin, Jonathan B.; Cable, Jaye E.; Swarzenski, Peter W.; Lindenberg, Mary K.

    2004-01-01

    Submarine ground water discharge is suggested to be an important pathway for contaminants from continents to coastal zones, but its significance depends on the volume of water and concentrations of contaminants that originate in continental aquifers. Ground water discharge to the Banana River Lagoon, Florida, was estimated by analyzing the temporal and spatial variations of Cl− concentration profiles in the upper 230 cm of pore waters and was measured directly by seepage meters. Total submarine ground water discharge consists of slow discharge at depths > ∼70 cm below seafloor (cmbsf) of largely marine water combined with rapid discharge of mixed pore water and estuarine water above ∼70 cmbsf. Cl− profiles indicate average linear velocities of ∼0.014 cm/d at depths > ∼70 cmbsf. In contrast, seepage meters indicate water discharges across the sediment-water interface at rates between 3.6 and 6.9 cm/d. The discrepancy appears to be caused by mixing in the shallow sediment, which may result from a combination of bioirrigation, wave and tidal pumping, and convection. Wave and tidal pumping and convection would be minor because the tidal range is small, the short fetch of the lagoon limits wave heights, and large density contacts are lacking between lagoon and pore water. Mixing occurs to ∼70 cmbsf, which represents depths greater than previously reported. Mixing of oxygenated water to these depths could be important for remineralization of organic matter.

  20. 33 CFR 151.1511 - Ballast water discharge standard (BWDS).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Ballast water discharge standard... SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Ballast Water Management for Control of Nonindigenous Species in...

  1. 33 CFR 151.2030 - Ballast water discharge standard (BWDS).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Ballast water discharge standard... SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Ballast Water Management for Control of Nonindigenous Species in...

  2. 33 CFR 151.2030 - Ballast water discharge standard (BWDS).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Ballast water discharge standard... SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Ballast Water Management for Control of Nonindigenous Species in...

  3. 33 CFR 151.2030 - Ballast water discharge standard (BWDS).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Ballast water discharge standard... SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Ballast Water Management for Control of Nonindigenous Species in...

  4. 33 CFR 151.1511 - Ballast water discharge standard (BWDS).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Ballast water discharge standard... SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Ballast Water Management for Control of Nonindigenous Species in...

  5. 33 CFR 151.1511 - Ballast water discharge standard (BWDS).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Ballast water discharge standard... SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Ballast Water Management for Control of Nonindigenous Species in...

  6. Grafted cellulose for PAHs removal present in industrial discharge waters

    NASA Astrophysics Data System (ADS)

    Euvrard, Elise; Druart, Coline; Poupeney, Amandine; Crini, Nadia; Vismara, Elena; Lanza, Tommaso; Torri, Giangiacomo; Gavoille, Sophie; Crini, Gregorio

    2014-05-01

    , the grafted cellulose showed lower adsorption capacities of PAHs (about 40% for the total PAH content) when they were in real effluents than they were in synthetic solutions. However, it was observed that PAH composition in discharge waters was different than in synthetic solutions, qualitatively and quantitatively. Despite the presence of numerous other substances in industrial effluents at high concentrations (for instance metals equal to mg/L and salts to g/L), the grafted cellulose was demonstrated as suitable to remove organic substances at trace levels like PAHs (equal to ng/L). Reference: [1] Vismara E., Melone L., Gastaldi G., Cosentino C., Torri G. J. Hazardous Mat. 170 (2009) 798-808. Acknowledgements: The authors thank Agence de l'Eau, FEDER and the Conseil regional de Franche-Comté for financial support (NIRHOFEX Program).

  7. Degradation of Verapamil hydrochloride in water by gliding arc discharge.

    PubMed

    Krishna, Syam; Maslani, Alan; Izdebski, Tomasz; Horakova, Marta; Klementova, Sarka; Spatenka, Petr

    2016-06-01

    This study investigated the influence of gliding arc plasma discharge on the degradation of Verapamil hydrochloride in water. The plasma discharge was characterized by means of optical emission spectroscopy. Spectra of various atomic and molecular species were observed. Aqueous solution of Verapamil hydrochloride was exposed to gliding arc discharge operated in continuous discharge at atmospheric pressure and room temperature. The identification of Verapamil, the degradation mechanisms of Verapamil and its transformation products were performed using liquid chromatography - mass spectrometry (HPLC-MS). Experimental results indicate that the atmospheric pressure gliding arc plasma treatment has noticeable effects on Verapamil with satisfactory degradation efficiency. Plausible mechanisms of the degradation were discussed. PMID:26953731

  8. Ignition modes of nanosecond discharge with bubbles in distilled water

    NASA Astrophysics Data System (ADS)

    Hamdan, Ahmad; Cha, Min Suk

    2015-10-01

    Here, we present the microscopic physical characteristics of nanosecond discharges with an array of bubbles in distilled water. In particular, applying a single high-voltage pulse, four delayed intensified charge-coupled device cameras successfully visualized four successive images during a single discharge event. We identified three distinctive modes of ignition inside a bubble, depending on the relative location of the bubble with respect to pin-to-hollow needle electrodes when a single bubble was located in an inter-electrode gap of 1 mm: anode-driven ignition, cathode-driven ignition, and co-ignition near both electrodes. Anode- and cathode-driven ignitions evolved into either a complete propagation of the streamer or an incomplete propagation, which were limited in location by proximity to an ignition location, while co-ignitions consistently showed complete propagation. When we increased the gap to 2 mm to accommodate multiple bubbles in the gap, an ignited bubble near the cathode was able to cause the ignition of an upper adjacent bubble. Bubble-bubble interface zones can also be spots of ignition, such that we observed simultaneous co-ignitions in the zones of bubble-bubble interfaces and near electrodes with triple bubbles. We compared the experimental results of discharge propagation with different ignition modes between Ar, He, and N2 bubbles. In addition, numerical simulations for static electric fields reasonably supported observed ignition behavior such that field intensity was locally enhanced.

  9. 61. VIEW OF SALT RIVER PROJECT WELL DISCHARGING WATER INTO ...

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

    61. VIEW OF SALT RIVER PROJECT WELL DISCHARGING WATER INTO THE ARIZONA CANAL NEAR 47TH AVENUE, LOOKING SOUTH Photographer: James Eastwood, July 1990 - Arizona Canal, North of Salt River, Phoenix, Maricopa County, AZ

  10. Detail of downstream face of dam showing water being discharged ...

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

    Detail of downstream face of dam showing water being discharged through diversion tube. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  11. Testing and analysis of PSV discharge force with water seal

    SciTech Connect

    Gu Fangyu; Li Pengzhou; Peng Yunkang

    1996-12-01

    Pilot-operated safety valve (PSV) of pressurizer is an important equipment in a NPP. It is an advanced type of safety valve and its discharge force is a key parameter to the design of overpressure protection systems. The discharge process can be affected by many complicated factors like volume and temperature distribution of water seal, discharge flow rate, and so on. One set of tests on discharge force have been completed under three water seal volumes and different temperature distributions by using a particular target to measure the transient dynamic response and modal analytical method to obtain the force function on the target. Meanwhile, the code Relap5/MOD2C is applied to calculate the force function. The results of tests and code analysis show that the application of Relap5/MOD2C in the calculation of PSV discharge force is successful and it has been used in the Qinshan NPP.

  12. Investigation of microplasma discharge in sea water for optical emission spectroscopy

    NASA Astrophysics Data System (ADS)

    Gamaleev, Vladislav; Okamura, Yo; Kitamura, Kensuke; Hashimoto, Yusuke; Oh, Jun-Seok; Furuta, Hiroshi; Hatta, Akimitsu

    2016-07-01

    Microplasma discharge in sea water for optical emission spectroscopy was investigated using a needle-to-plane electrode system. The electrodes of a Pd needle and a Pt plate were placed with a gap of 25 µm in typical artificial sea water or locally sampled natural deep sea water. A pulse current source, consisting of a MOSFET switch, a capacitor, an inductor and the resistance of the sea water between the electrodes, was used. The circuit parameters were optimized to decrease the breakdown voltage and the spark duration to suppress erosion of the electrodes. Using a microgap configuration, spark discharges were reproducibly ignited in the highly conductive sea water at low breakdown voltages. The ignition of spark discharges required not only a critical voltage sufficient for breakdown, but also a critical energy for preheating of the sea water, sufficient for bubble formation. The possibility of using optical emission spectroscopy of microplasma in water is shown for identifying elemental composition of sea water.

  13. Health risk assessment for radium discharged in produced waters

    SciTech Connect

    Hamilton, L.D.; Meinhold, A.F.; Nagy, J.

    1991-12-31

    Produced water generated during the production of oil and gas can contain enhanced levels of radium. This naturally occurring radioactive material (NORM) is discharged into freshwater streams, estuarine, coastal and outer continental shelf waters. Large volumes of produced waters are discharged to coastal waters along the Gulf Coast of Louisiana. The Gulf of Mexico is an important producer of fish and shellfish, and there is concern that radium discharged to coastal Louisiana could contaminate fish and shellfish used by people for food, and present a significant increase in cancer risk. This paper describes a screening-level assessment of the potential cancer risks posed by radium discharged to coastal Louisiana in oil-field produced waters. This screening analysis was performed to determine if a more comprehensive and realistic assessment is necessary, and because of the conservative assumptions embedded in the analysis overestimates the risk associated with the discharge of radium in produced waters. Two isotopes of radium (Ra-226 and Ra-228) are the radionuclides of most concern in produced water in terms of potential human health effects.

  14. Health risk assessment for radium discharged in produced waters

    SciTech Connect

    Hamilton, L.D.; Meinhold, A.F.; Nagy, J.

    1991-01-01

    Produced water generated during the production of oil and gas can contain enhanced levels of radium. This naturally occurring radioactive material (NORM) is discharged into freshwater streams, estuarine, coastal and outer continental shelf waters. Large volumes of produced waters are discharged to coastal waters along the Gulf Coast of Louisiana. The Gulf of Mexico is an important producer of fish and shellfish, and there is concern that radium discharged to coastal Louisiana could contaminate fish and shellfish used by people for food, and present a significant increase in cancer risk. This paper describes a screening-level assessment of the potential cancer risks posed by radium discharged to coastal Louisiana in oil-field produced waters. This screening analysis was performed to determine if a more comprehensive and realistic assessment is necessary, and because of the conservative assumptions embedded in the analysis overestimates the risk associated with the discharge of radium in produced waters. Two isotopes of radium (Ra-226 and Ra-228) are the radionuclides of most concern in produced water in terms of potential human health effects.

  15. Evaluating the generation efficiency of hydrogen peroxide in water by pulsed discharge over water surface and underwater bubbling pulsed discharge

    NASA Astrophysics Data System (ADS)

    Shang, Kefeng; Li, Jie; Wang, Xiaojing; Yao, Dan; Lu, Na; Jiang, Nan; Wu, Yan

    2016-01-01

    Pulsed electric discharge over water surface/in water has been used to generate reactive species for decomposing the organic compounds in water, and hydrogen peroxide (H2O2) is one of the strong reactive species which can be decomposed into another stronger oxidative species, hydroxyl radical. The production efficacy of H2O2 by a gas phase pulsed discharge over water surface and an underwater bubbling pulsed discharge was evaluated through diagnosis of H2O2 by a chemical probe method. The experimental results show that the yield and the production rate of H2O2 increased with the input energy regardless of the electric discharge patterns, and the underwater bubbling pulsed discharge was more advantageous for H2O2 production considering both the yield and the production rate of H2O2. Results also indicate that the electric discharge patterns also influenced the water solution properties including the conductivity, the pH value and the water temperature.

  16. Characterization of highly transient EUV emitting discharges

    NASA Astrophysics Data System (ADS)

    van der Mullen, Joost; Kieft, Erik; Broks, Bart

    2006-07-01

    The method of disturbed Bilateral Relations (dBR) is used to characterize highly transient plasmas that are used for the generation of Extreme Ultra Violet (EUV), i.e. radiation with a wavelength around 13.5 nm. This dBR method relates equilibrium disturbing to equilibrium restoring processes and follows the degree of equilibrium departure from the global down to the elementary plasma-level. The study gives global values of the electron density and electron temperature. Moreover, it gives a method to construct the atomic state distribution function (ASDF). This ASDF, which is responsible for the spectrum generated by the discharge, is found to be far from equilibrium. There are two reasons for this: first, systems with high charge numbers radiate strongly, second the highly transient behaviour makes that the distribution over the various ionization stages lags behind the temperature evolution.

  17. Sounding experiments of high pressure gas discharge

    SciTech Connect

    Biele, Joachim K.

    1998-07-10

    A high pressure discharge experiment (200 MPa, 5{center_dot}10{sup 21} molecules/cm{sup 3}, 3000 K) has been set up to study electrically induced shock waves. The apparatus consists of the combustion chamber (4.2 cm{sup 3}) to produce high pressure gas by burning solid propellant grains to fill the electrical pump chamber (2.5 cm{sup 3}) containing an insulated coaxial electrode. Electrical pump energy up to 7.8 kJ at 10 kV, which is roughly three times of the gas energy in the pump chamber, was delivered by a capacitor bank. From the current-voltage relationship the discharge develops at rapidly decreasing voltage. Pressure at the combustion chamber indicating significant underpressure as well as overpressure peaks is followed by an increase of static pressure level. These data are not yet completely understood. However, Lorentz forces are believed to generate pinching with subsequent pinch heating, resulting in fast pressure variations to be propagated as rarefaction and shock waves, respectively. Utilizing pure axisymmetric electrode initiation rather than often used exploding wire technology in the pump chamber, repeatable experiments were achieved.

  18. Risk assessment for produced water discharges to Louisiana open bays

    SciTech Connect

    Meinhold, A.F.; Holtzman, S.; DePhillips, M.P.

    1995-11-01

    Potential human health and environmental impacts from discharge of produced water to the Gulf of Mexico concern regulators at the State and Federal levels, environmental interest groups, industry and the public. Current regulations in the United States require or propose azero discharge limit for coastal facilities based primarily on studies performed in low energy,poorly flushed environments. Produced water discharges in coastal Louisiana, however,include a number located in open bays, where potential and impacts are likely to be larger than the minimal impacts associated with offshore discharges, but smaller than those demonstrated in low-energy canal environments. This paper summarizes results of a conservative screening-level health and ecological assessment for contaminants discharged in produced water to open bays in Louisiana, and reports results of a probabilistic human health risk assessment for radium and lead. The initial human health and ecological risk assessments consisted of conservative screening analyses that identified potentially important contaminants and excluded others from further consideration. A more quantitative probabilistic risk assessment was completed for the human health effects of the two contaminants identified in this screen: radium and lead. This work is part of a series of studies on the health and ecological risks from discharges of produced water to the Gulf of Mexico, supported by the United States Department of Energy (USDOE).

  19. Pulsed electrical discharge in gas bubbles in water

    NASA Astrophysics Data System (ADS)

    Gershman, Sophia

    A phenomenological picture of pulsed electrical discharge in gas bubbles in water is produced by combining electrical, spectroscopic, and imaging methods. The discharge is generated by applying one microsecond long 5 to 20 kilovolt pulses between the needle and disk electrodes submerged in water. A gas bubble is generated at the tip of the needle electrode. The study includes detailed experimental investigation of the discharge in argon bubbles and a brief look at the discharge in oxygen bubbles. Imaging, electrical characteristics, and time-resolved optical emission data point to a fast streamer propagation mechanism and formation of a plasma channel in the bubble. Spectroscopic methods based on line intensity ratios and Boltzmann plots of line intensities of argon, atomic hydrogen, and argon ions and the examination of molecular emission bands from molecular nitrogen and hydroxyl radicals provide evidence of both fast beam-like electrons and slow thermalized ones with temperatures of 0.6 -- 0.8 electron-volts. The collisional nature of plasma at atmospheric pressure affects the decay rates of optical emission. Spectroscopic study of rotational-vibrational bands of hydroxyl radical and molecular nitrogen gives vibrational and rotational excitation temperatures of the discharge of about 0.9 and 0.1 electron-volt, respectively. Imaging and electrical evidence show that discharge charge is deposited on the bubble wall and water serves as a dielectric barrier for the field strength and time scales of this experiment. Comparing the electrical and imaging information for consecutive pulses applied at a frequency of 1 Hz indicates that each discharge proceeds as an entirely new process with no memory of the previous discharge aside from long-lived chemical species, such as ozone and oxygen. Intermediate values for the discharge gap and pulse duration, low repetition rate, and unidirectional character of the applied voltage pulses make the discharge process here unique

  20. Electric discharge in the water: physics of formation and radiative characteristics.

    NASA Astrophysics Data System (ADS)

    Anpilov, Andrei; Barkhudarov, Eduard; Kozlov, Yurii; Kossyi, Igor; Silakov, Valerii; Temchin, Savelii

    2004-09-01

    ELECTRIC DISCHARGE IN THE WATER: PHYSICS OF FORMATION AND RADIATIVE CHARACTERISTICS 2.10. Lighting plasmas. 2.26. Other plasma topics. A.M.Anpilov, E.M.Barkhudarov, Yu.N.Kozlov, I.A.Kossyi, V.P.Silakov and S.M.Temchin Two types of electric discharge in the water have been investigated: discharge between two electrodes and multielectrode gliding surface discharge. Results are presented from experimental studies of the prebreakdown phase of an electric discharge between the point (anode) and plane (cathode) electrodes immersed in the water with different initial conductivity. When a high-voltage pulse is applied, the induced conductivity is detected in the discharge gap. Its value is one order of magnitude higher than the initial one. It is shown that the induced conductivity increases almost linearly with initial conductivity. The induced conductivity correlates with the UV emission from the cathode surface. A qualitative analysis of the experimental results is performed. Investigations of a spectrum of radiation of discharge in water have been carried out. On the base of broadening and shifting of atomic hydrogen and oxygen lines electron density in a prebreakdown as well as breakdown stages has been determined. Results are presented from investigations of multispark electric discharge in water excited along multielectrode metal-dielectric systems with gas supply into the interelectrode gaps. The intensity distribution of discharge radiation in the region covering the biologically active soft UV (190 £l£430 nm) has been determined and the absolute number of quanta in this wavelength interval has been measured. The potentiality of the gliding surface discharge in water for its disinfection is analysed.

  1. ESTIMATING FLOW AND FLUX OF GROUND-WATER DISCHARGE USING WATER TEMPERATURE AND VELOCITY. (R827961)

    EPA Science Inventory

    The nature of ground water discharge to a stream has important implications for nearby ground water flow, especially with respect to contaminant transport and well-head protection. Measurements of ground water discharge were accomplished in this study using (1) differences bet...

  2. Discharge current modes of high power impulse magnetron sputtering

    SciTech Connect

    Wu, Zhongzhen Xiao, Shu; Ma, Zhengyong; Cui, Suihan; Ji, Shunping; Pan, Feng; Tian, Xiubo; Fu, Ricky K. Y.; Chu, Paul K.

    2015-09-15

    Based on the production and disappearance of ions and electrons in the high power impulse magnetron sputtering plasma near the target, the expression of the discharge current is derived. Depending on the slope, six possible modes are deduced for the discharge current and the feasibility of each mode is discussed. The discharge parameters and target properties are simplified into the discharge voltage, sputtering yield, and ionization energy which mainly affect the discharge plasma. The relationship between these factors and the discharge current modes is also investigated.

  3. Fast imaging of intermittent electrospraying of water with positive corona discharge

    NASA Astrophysics Data System (ADS)

    Pongrác, B.; Kim, H. H.; Janda, M.; Martišovitš, V.; Machala, Z.

    2014-08-01

    The effect of the electrospraying of water in combination with a positive direct current (dc) streamer corona discharge generated in air was investigated in this paper. We employed high-speed camera visualizations and oscilloscopic discharge current measurements in combination with an intensified charge-coupled device camera for fast time-resolved imaging. The repetitive process of Taylor cone formation and droplet formation from the mass fragments of water during the electrospray was visualized. Depending on the applied voltage, the following intermittent modes of electrospraying typical for water were observed: dripping mode, spindle mode, and oscillating-spindle mode. The observed electrospraying modes were repetitive with a frequency of a few hundreds of Hz, as measured from the fast image sequences. This frequency agreed well with the frequency of the measured streamer current pulses. The presence of filamentary streamer discharges at relatively low voltages probably prevented the establishment of a continuous electrospray in the cone-jet mode. After each streamer, a positive glow corona discharge was established on the water filament tip, and it propagated from the stressed electrode along with the water filament elongation. The results show a reciprocal character of intermittent electrospraying of water, and the presence of corona discharge, where both the electrospray and the discharge affect each other. The generation of a corona discharge from the water cone depended on the repetitive process of the cone formation. Also, the propagation and curvature of the water filament were influenced by the discharge and its resultant space charge. Furthermore, these phenomena were partially influenced by the water conductivity.

  4. Spatial organization of stream water discharge and chemistry in forested headwaters

    NASA Astrophysics Data System (ADS)

    Egusa, T.; Ohte, N.; Oda, T.; Suzuki, M.

    2013-12-01

    It has long been known that, in small catchments, stream water discharge and chemistry are highly variable but the variability decreases gradually with an increase in the catchment area. Wood et al. (1988) showed that model calculations of infiltration and the runoff rate became constant above a certain threshold area. They defined the threshold area as the representative elementary area (REA) and stated that above the REA only minimum knowledge of the underlying parameters is needed to explain the stream water discharge and chemistry. Subsequently, empirical studies were conducted in several catchments. These studies all verified the existence of an REA in real catchments and indicated that the REA values differed among catchments. The results also suggested that the confluence processes of stream water discharge and chemistry differed among catchments. However, it has not been clarified how the confluence processes behave and why processes differ among catchments. One of the unclear things to resolve is whether the variability of discharge and chemistry among small catchments can be regarded as randomness or if it is organized. Two previous studies examined it and reported the opposite results. Woods et al. (1995) reported that organization was apparent from their observations of specific discharge. However, Asano and Uchida (2010) stated that their results for SiO2 could be regarded as randomness. These studies targeted different observed items and different catchments. Therefore, general knowledge about organization of stream water discharge and chemistry has not been obtained. We observed spatial variability of stream water discharge and chemistry and examined the existence of spatial organization by using the statistical method. Our objective was to elucidate whether the spatial organization exists about stream water discharge and chemistry. Observations were conducted in three forested catchments in Japan. Snapshot samplings of stream water discharge and

  5. Publ 420, management of water discharge

    SciTech Connect

    Not Available

    1990-01-01

    This book describes coagulation and flocculation theory and methods used by petroleum refiners to optimize end-of-pipe treatment of process water and the dewatering of sludges. Some of the topics covered are systems optimization; the theory and mechanisms of coagulation and flocculation; properties of suspended solids; chemicals used for coagulation and flocculation, including synthetic polyelectrolytes; destabilization models; and recommendations for use of granular-media filtration, dissolved- and induced-air flotation, activated-sludge treatment, and sludge dewater.

  6. How can we get a better estimation for vegetation water uptake in groundwater discharge areas using high frequency soil moisture data

    NASA Astrophysics Data System (ADS)

    Gribovszki, Zoltán; Kalicz, Péter

    2014-05-01

    Evapotranspiration induces diurnal signal of soil moisture, and also of water table in shallow water table environments. Shallow water table diurnal signal was widespreadly used for estimation of groundwater uptake by plants. The limitation of all groundwater signal based methods lies in the difficulty of specific yield estimation. In this paper a new technique is demonstrated by which more exact evapotranspiration values can be calculated from aggregated soil moisture profile dataset taking into account diurnally changing replenishment rate. The technique is of great benefit to provide sufficient accuracy without soil specific calibration. New technique was successfully tested on the soil moisture profile dataset of a riparian alder forest in Hidegvíz Valley experimental catchment in the summer of 2013. Comparing traditional evapotranspiration estimation from soil moisture data the new technique gives much higher water uptake taking into account soil moisture continuous replenishment from shallow groundwater. The water uptake seems to be acceptable if oasis effect is taken into account in a well watered valley situation in a period when hot and dry environment can add significant amount of heat enhancing transpiration. Soil moisture replenishment rates from groundwater can provide high portion (60-80This publication has been supported by funds from: OTKA (NN 79835) and TÁMOP-4.2.2.A-11/1/KONV-2012-0013 project. The research of Zoltán Gribovszki was supported by the European Union and the State of Hungary, co-financed by the European Social Fund in the framework of TÁMOP 4.2.4. A/2-11-1-2012-0001 'National Excellence Program'. Keywords: groundwater evapotranspiration, diurnal fluctuation, forest vegetation

  7. Pulse volume discharges in high pressure gases

    NASA Astrophysics Data System (ADS)

    Yamshchikov, V. A.

    2015-11-01

    New approach for suppression of plasma inhomogeneities and instabilities in the volume self-sustained discharge is offered. The physical model is offered and conditions of obtaining extremely homogeneous self-sustained discharge are defined (with full suppression of plasma inhomogeneity and instability). Results of calculations agree with experiments.

  8. Effects of a nearshore wastewater discharge: Water column and sediment pore water toxicity

    SciTech Connect

    Krause, P.R.; Carr, R.S.

    1995-12-31

    The relationship between water column and sediment pore water toxicity was investigated near a municipal-industrial wastewater discharge in southern Texas. Toxicity associated with effluent distributions in the water column are known to vary in both time and space. Toxicity of sediment, however, is often more stable over time. Sediment can serve as a long-term integrator of toxicity in areas subject to chronic exposure of effluents. This study addressed the relationship between water column toxicity and that found in the sediments on both spatial and temporal scales. Four 2 Km transacts were established around a nearshore wastewater outfall. Eight stations along each transact were sampled for both surface waters and sediment pore water toxicity. Toxicity was determined using a modified sea urchin fertilization test. Surface waters were sampled and tested for eight consecutive months, while sediment pore waters were sampled on three occasions over the length of this study. Results have shown that toxicity in receiving waters was a good indicator to trace movements of the highly variable effluent plume. The distribution of effluent in the water column, and hence water column toxicity, was primarily driven by local wind conditions. Toxicity in sediment porewater was, much less variable and more evenly distributed over the study site. Sediment pore water toxicity was also a good predictor of the distribution of benthic infaunal invertebrates over much of the study site.

  9. Water discharge from Lone Star Geyser, Yellowstone NP, WY

    NASA Astrophysics Data System (ADS)

    Murphy, F.; Randolph-Flagg, N. G.; Hurwitz, S.

    2014-12-01

    During four days in April, 2014 we made a series of measurements at Lone Star Geyser in Yellowstone National Park, WY. This work included the continuous measurement of liquid water discharge from the geyser and some nearby not springs, and concurrent meteorological measurements. The discharge of the geyser and the hot springs was measured in channels that carry the water to the Firehole River. We found that average measured discharge varies from day to night, likely due to melting of geyser-generated and meteoric snow during warmer daylight hours and freezing of erupted liquid and vapor during the night. The nearby hot springs contribute a nearly constant flow of about 3 l/s to the Firehole River, while during eruptions the total discharge increases to a maximum of about 25 l/s. Two small geysers within 5 meters of the Lone Star Geyser cone were observed to erupt during a time when Lone Star Geyser was not erupting. The water discharged from these small geysers is a very small fraction of that from Lone Star Geyser.

  10. [High-quality hospital discharge summaries - general practitioners expectations].

    PubMed

    Bally, Klaus; Lingenhel, Sabine; Tschudi, Peter

    2012-01-01

    Hospital discharge summaries ensure treatment continuity after hospital discharge. In Switzerland discharge letters are a celebrated custom and a tool for training young colleagues. The primary purpose is to guarantee high-quality care of patients treated by hospital staff and general practitioners. From the perspective of the patient's general practitioner discharge summaries should convey current and accurate medically important patient data to the physician responsible for follow-up care. In the era of highly developed electronic data transfer and introduction of diagnose related groups (DRGs), it will be necessary to transmit hospital discharge information selectively to different target groups. Nevertheless data protection and medical secret must be complied with. PMID:22198930

  11. Residence time of water discharging from the Hanging Gardens of Zion Park

    USGS Publications Warehouse

    Kimball, B.A.; Christensen, P.K.

    1996-01-01

    The Hanging Gardens are a unique feature of Zion National Park. Knowledge of the source and residence time of water discharging from the Hanging Gardens is necessary to help preserve these features. Ground-water chemical and isotopic data distinguish the discharge from seeps and springs into two groups, one of low and one of high conductivity. Water with low conductivity likely originates as recharge near the steps and springs, and it only interacts with the Navajo Sandstone. High conductivity water, on the other hand, originates as recharge on the tops of plateaus to the east, where it interacts with marine rocks of the Carmel Formation. Carbon dating of these ground waters indicates that the low conductivity water is essentially modern recharge, while the high conductivity water was recharged 1,000 to 4,000 years ago.The Hanging Gardens are a unique feature of Zion National Park. Knowledge of the source and residence time of water discharging from the Hanging Gardens is necessary to help preserve these features. Ground-water chemical and isotopic data distinguish the discharge from seeps and springs into two groups, one of low and one of high conductivity. Water with low conductivity likely originates as recharge near the seeps and springs, and it only interacts with the Navajo Sandstone. High conductivity water, on the other hand, originates as recharge on the tops of plateaus to the cast, where it interacts with marine rocks of the Carmel Formation. Carbon dating of these ground waters indicates that the low conductivity water is essentially modern recharge, while the high conductivity water was recharged 1,000 to 4,000 years ago.

  12. PURIFICATION OF WATERS DISCHARGED FROM POLISH LIGNITE MINES

    EPA Science Inventory

    The exploitation of lignite deposits is linked with the necessity of lowering the groundwater table and dewatering the mine of precipitation. A large percentage of the discharge waters requires purification prior to delivery of receiving streams. The chief pollutants of these wat...

  13. 1. Credit TCL. South elevation. Note water discharging from all ...

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

    1. Credit TCL. South elevation. Note water discharging from all five tailraces. The portion of the powerhouse erected in 1900-01 is on the right. The 1906 and 1908 additions are on the left. - Battle Creek Hydroelectric System, Battle Creek & Tributaries, Red Bluff, Tehama County, CA

  14. FTIR Analysis of Flowing Afterglow from a High-Frequency Spark Discharge

    NASA Astrophysics Data System (ADS)

    White, Allen; Hieftje, Gary M.; Ray, Steve; Pfeuffer, Kevin

    2014-06-01

    Plasmas are often used as ionization sources for ambient mass spectrometry (AMS). Here, the flowing afterglow of a novel high-energy spark discharge system, operated in nitrogen at high repetition rates, is investigated as a source for AMS. The spark discharge here is the same as that of an automobile ignition circuit.Combustion in automobile engines is initiated by a spark ignition system that is designed to deliver short-duration,high-voltage sparks to multiple engine cylinders. The arrangement utilized in this study is a modified discharge configuration designed to produce similarly short-duration, high-voltage discharges. It consists of an automotive ignition coil that is activated by a spark initiation circuit that discharges in turn into a cell with neutral gas input flow and ultimately into the collection orifice of a mass spectrometer. The discharge voltage is approximately 40kV at 800 Hz. High-frequency spark discharges in a nitrogen flow produce reagent ions such as NO+. In order to better evaluate the effectiveness of the discharge in producing reagent ions, an FTIR is utilized to measure IR active species such as nitric oxide, hydroxide, ozone, and water in the afterglow of the spark discharge during variation of discharge parameters. Time-resolved IR emission spectra provide additional insight into the reagent ion production mechanisms.

  15. Long-living plasmoids from an atmospheric water discharge

    NASA Astrophysics Data System (ADS)

    Versteegh, A.; Behringer, K.; Fantz, U.; Fussmann, G.; Jüttner, B.; Noack, S.

    2008-05-01

    Ball-like plasmoids were generated from discharging a capacitor bank via a water surface. In the autonomous stage after current zero they have diameters up to 0.2 m and lifetimes of some hundreds of milliseconds, thus resembling ball lightning in some way. They were studied by applying high speed cameras, electric probes, calorimetric measurements, and spectroscopy. The plasmoids are found to consist of a true plasma surrounded by a cold envelope. Decreasing electron densities in the order of 1020-1022 m-3 were measured from Stark broadening in the initial (formation) phase. The electron temperature is estimated to be 2000-5000 K during most of the plasmoid's lifetime. The temperature of the neutral particles can exceed 1300 K. Calcium hydroxide molecular band emission is the major source of visible radiation in the autonomous phase. Chemiluminescence reactions between dissociation products of water and dissolved calcium are proposed as a source for this emission. The plasmoid's colder boundary layer consists of electric double layers that may be attributed to the characteristic shape of the balls.

  16. High-repetition-rate short-pulse gas discharge.

    PubMed

    Tulip, J; Seguin, H; Mace, P N

    1979-09-01

    A high-average-power short-pulse gas discharge is described. This consists of a volume-preionized transverse discharge of the type used in gas lasers driven by a Blumlein energy storage circuit. The Blumlein circuit is fabricated from coaxial cable, is pulse-charged from a high-repetition-rate Marx-bank generator, and is switched by a high-repetition-rate segmented rail gap. The operation of this discharge under conditions typical of rare-gas halide lasers is described. A maximum of 900 pps was obtained, giving a power flow into the discharge of 30 kW. PMID:18699678

  17. Bio-Decontamination of Water and Surfaces by DC Discharges in Atmospheric Air

    NASA Astrophysics Data System (ADS)

    Machala, Zdenko; Tarabová, Barbora; Pelach, Michal; Šipoldová, Zuzana; Hensel, Karol; Janda, Mário; Šikurová, Libuša

    Two types of DC-driven atmospheric air discharges, including a streamer corona and a transient spark with short high current pulses of limited energy, were employed for bio-decontamination of water and various surfaces (agar plates, plastic foils, human teeth) contaminated by bacteria or spores (Salmonella typhimurium, Bacillus cereus). Both discharges generate cold non-equilibrium plasma. The discharges combined with the electro-spraying of the treated water through the needle electrode lead to fast and efficient bio-decontamination. Experiments comparing direct and indirect plasma effects, oxidation stress measurements in the cell membranes, and chemical changes induced in the treated water enable assessment of the plasma agents being responsible for microbial inactivation. Radicals and reactive oxygen species seem to be dominant biocidal agents, although deeper understanding of the plasma-induced water chemistry and of the temporal evolution of the bio-inactivation processes is needed.

  18. Characterizing hydrology and the importance of ground-water discharge in natural and constructed wetlands

    USGS Publications Warehouse

    Hunt, Randall J.; Walker, John F.; Krabbenhoft, David P.

    1999-01-01

    Although considered the most important component for the establishment and persistence of wetlands, hydrology has been hard to characterize and linkages between hydrology and other environmental conditions are often poorly understood. In this work, methods for characterizing a wetland’s hydrology from hydrographs were developed, and the importance of ground water to the physical and geochemical conditions in the root zone was investigated. Detailed sampling of nearly continuous hydrographs showed that sites with greater ground-water discharge had higher water tables and more stable hydrographs. Subsampling of the continuous hydrograph failed to characterize the sites correctly, even though the wetland complex is located in a strong regional ground-water-discharge area. By comparing soil-moisture-potential measurements to the water-table hydrograph at one site, we noted that the amount of root-zone saturation was not necessarily driven by the water-table hydrograph but can be a result of other soil parameters (i.e., soil texture and associated capillary fringe). Ground-water discharge was not a significant determinant of maximum or average temperatures in the root zone. High ground-water discharge was associated with earliest date of thaw and shortest period of time that the root zone was frozen, however. Finally, the direction and magnitude of shallow ground-water flow was found to affect the migration and importance of a geochemical species. Areas of higher ground-water discharge had less downward penetration of CO2 generated in the root zone. In contrast, biotically derived CO2 was able to penetrate the deeper ground-water system in areas of ground-water recharge. Although ground-water flows are difficult to characterize, understanding these components is critical to the success of wetland restoration and creation efforts.

  19. Can humic water discharge counteract eutrophication in coastal waters?

    PubMed

    Andersson, Agneta; Jurgensone, Iveta; Rowe, Owen F; Simonelli, Paolo; Bignert, Anders; Lundberg, Erik; Karlsson, Jan

    2013-01-01

    A common and established view is that increased inputs of nutrients to the sea, for example via river flooding, will cause eutrophication and phytoplankton blooms in coastal areas. We here show that this concept may be questioned in certain scenarios. Climate change has been predicted to cause increased inflow of freshwater to coastal areas in northern Europe. River waters in these areas are often brown from the presence of high concentrations of allochthonous dissolved organic carbon (humic carbon), in addition to nitrogen and phosphorus. In this study we investigated whether increased inputs of humic carbon can change the structure and production of the pelagic food web in the recipient seawater. In a mesocosm experiment unfiltered seawater from the northern Baltic Sea was fertilized with inorganic nutrients and humic carbon (CNP), and only with inorganic nutrients (NP). The system responded differently to the humic carbon addition. In NP treatments bacterial, phytoplankton and zooplankton production increased and the systems turned net autotrophic, whereas the CNP-treatment only bacterial and zooplankton production increased driving the system to net heterotrophy. The size-structure of the food web showed large variations in the different treatments. In the enriched NP treatments the phytoplankton community was dominated by filamentous >20 µm algae, while in the CNP treatments the phytoplankton was dominated by picocyanobacteria <5 µm. Our results suggest that climate change scenarios, resulting in increased humic-rich river inflow, may counteract eutrophication in coastal waters, leading to a promotion of the microbial food web and other heterotrophic organisms, driving the recipient coastal waters to net-heterotrophy. PMID:23637807

  20. Water withdrawals, use, discharge, and trends in Florida, 2000

    USGS Publications Warehouse

    Marella, Richard L.

    2004-01-01

    River, Lake Okeechobee and associated canals, and the canals associated with the headwaters of the Upper St. Johns River. Freshwater withdrawals increased 46 percent and saline water withdrawals increased 25 percent in Florida between 1970 and 2000. Ground-water withdrawals increased 82 percent, and surface-water withdrawals increased 10 percent during this period. Between 1970 and 2000, total freshwater withdrawals increased for public supply by 176 percent and for agricultural self-supplied by 87 percent; withdrawals for commercial-industrial self-supplied decreased by 37 percent, and power generation (thermoelectric) decreased by 57 percent. Recreational irrigation withdrawals increased 127 percent between 1985 and 2000. Between 1995 and 2000, freshwater withdrawals increased 13 percent, and saline withdrawals increased 9 percent. An estimated 52 percent of the freshwater withdrawn in Florida was consumed; the remaining 48 percent was returned for further use. Domestic wastewater discharged in 2000 totaled 1,495 Mgal/d, of which 44 percent was discharged to surface waters, 34 percent to the ground through land application systems, and 22 percent to deep injection wells. Domestic wastewater discharge increased by 33 percent between 1985 and 2000, but decreased by 3 percent between 1995 and 2000. An estimated 11.21 million people were served by domestic wastewater systems in 2000, whereas the remaining 4.77 million people discharged wastewater to more than 1.95 million septic tanks. Discharge from the septic tanks was estimated to be 263 Mgal/d in 2000.

  1. ROS/RNS Production in Water Using Various Discharge Plasma

    NASA Astrophysics Data System (ADS)

    Takahashi, Kazuhiro; Satoh, Kohki; Itoh, Hidenori; Kawaguchi, Hideki; Timoshkin, Igor; Given, Martin; MacGregor, Scott

    2015-09-01

    A pulsed discharge, a DC corona discharge and an atmospheric pressure plasma jet are generated above water, the off-gas of a packed-bed dielectric barrier discharge (PB-DBD) is sparged into water, and then reactive oxygen species and reactive nitrogen species in the water are investigated. H2O2, NO3- and a trace of NO2- are produced in the water after the plasma exposure. H2O2 concentration decreases when NO3- concentration increases, so that this is likely that OH radical to produce H2O2 by OH + OH -->H2O2 is consumed in the NO3- production by NO2 + OH --> HNO3 --> NO3-+ H+ (in water). Since no species is detected in water by the sparging of the PB-DBD off-gas containing more than 1000 ppm of O3, O3 does not contribute to produce H2O2 in water. Further, only NO3- is produced by the sparging of the off-gas containing N2O5 and HNO3. This leads that H2O2 and NO2- can be produced by short-lifetime species in plasma. In this work, the highest generation efficiency of H2O2 and NO2- are respectively 3,820 μg/Wh and 830 μg/Wh by the pulsed-plasma exposure, and that of NO3- is 2,530 μg/Wh by the off-gas sparging of the PB-DBD.

  2. A Particular River-Whiting Phenomenon Caused by Discharge of Hypolimnetic Water from a Stratified Reservoir

    PubMed Central

    Chen, Jingan; Yang, Haiquan; Zhang, David Dian; Xu, Dan; Luo, Jing; Wang, Jingfu

    2015-01-01

    A particular river-whiting phenomenon occurred in the early 2000s in the Xiaoche River and since then it has been reoccurring from June to November each year. Residents were surprised by this phenomenon and worried about it. This study was designed to reveal the forming mechanism of the river-whiting phenomenon. A comparison of T, EC, ORP, DO, TDS and δ34S in the culvert water and discharge pipe water with that in the water column of Aha Reservoir strongly indicated that the culvert water and discharge pipe water derived primarily from the hypolimnetic reservoir water. When the hypolimnetic water enriched in SO42- and H2S, through seepage from the penstock, flows into the Xiaoche River, the water's supersaturation degree with respect to CaSO4 is increased as a result of increased temperature and DO, thus colloid CaSO4 can be formed. This is the essential cause of the river-whiting phenomenon. The sources of high concentrations of SO42- and H2S in hypolimnetic water include not only direct SO42- and H2S input of acid mine drainage as a result of irrational coal mining in the watershed, but also the sulfur-enriched surface sediments which may release H2S through the sulfate reduction processes. The contaminated sediment has acted as an important contamination source for sulfur to the overlying water in Aha Reservoir. There are more than 50,000 large dams in the world until now. With the increase of reservoir age and the persistent accumulation of pollutants within the reservoir system, discharged hypolimnetic water may contain high levels of pollutants and lead to unpredicted disasters. More investigations are needed to illuminate the water quality condition of discharge water from reservoirs and estimate its impacts on the downstream eco-environment. PMID:26361219

  3. A Particular River-Whiting Phenomenon Caused by Discharge of Hypolimnetic Water from a Stratified Reservoir.

    PubMed

    Chen, Jingan; Yang, Haiquan; Zhang, David Dian; Xu, Dan; Luo, Jing; Wang, Jingfu

    2015-01-01

    A particular river-whiting phenomenon occurred in the early 2000s in the Xiaoche River and since then it has been reoccurring from June to November each year. Residents were surprised by this phenomenon and worried about it. This study was designed to reveal the forming mechanism of the river-whiting phenomenon. A comparison of T, EC, ORP, DO, TDS and δ34S in the culvert water and discharge pipe water with that in the water column of Aha Reservoir strongly indicated that the culvert water and discharge pipe water derived primarily from the hypolimnetic reservoir water. When the hypolimnetic water enriched in SO42- and H2S, through seepage from the penstock, flows into the Xiaoche River, the water's supersaturation degree with respect to CaSO4 is increased as a result of increased temperature and DO, thus colloid CaSO4 can be formed. This is the essential cause of the river-whiting phenomenon. The sources of high concentrations of SO42- and H2S in hypolimnetic water include not only direct SO42- and H2S input of acid mine drainage as a result of irrational coal mining in the watershed, but also the sulfur-enriched surface sediments which may release H2S through the sulfate reduction processes. The contaminated sediment has acted as an important contamination source for sulfur to the overlying water in Aha Reservoir. There are more than 50,000 large dams in the world until now. With the increase of reservoir age and the persistent accumulation of pollutants within the reservoir system, discharged hypolimnetic water may contain high levels of pollutants and lead to unpredicted disasters. More investigations are needed to illuminate the water quality condition of discharge water from reservoirs and estimate its impacts on the downstream eco-environment. PMID:26361219

  4. Risk assessment for produced water discharges to Louisiana Open Bays

    SciTech Connect

    Meinhold, A.F.; DePhillips, M.P.; Holtzman, S.

    1995-06-23

    Data were collected prior to termination of discharge at three sites (including two open bay sites at Delacroix Island and Bay De Chene) for the risk assessments. The Delacroix Island Oil and Gas Field has been in production since the first well drilling in 1940; the Bay De Chene Field, since 1942. Concentrations of 226Ra, 228Ra, 210Po, and 228Th were measured in discharges. Radium conc. were measured in fish and shellfish tissues. Sediment PAH and metal conc. were also available. Benthos sampling was conducted. A survey of fishermen was conducted. The tiered risk assessment showed that human health risks from radium in produced water appear to be small; ecological risk from radium and other radionuclides in produced water also appear small. Many of the chemical contaminants discharged to open Louisiana bays appear to present little human health or ecological risk. A conservative screening analysis suggested potential risks to human health from Hg and Pb and a potential risk to ecological receptors from total effluent, Sb, Cd, Cu, Pb, Ni, Ag, Zn, and phenol in the water column and PAHs in sediment; quantitiative risk assessments are being done for these contaminants.

  5. Fuzzy Neural Networks for water level and discharge forecasting

    NASA Astrophysics Data System (ADS)

    Alvisi, Stefano; Franchini, Marco

    2010-05-01

    A new procedure for water level (or discharge) forecasting under uncertainty using artificial neural networks is proposed: uncertainty is expressed in the form of a fuzzy number. For this purpose, the parameters of the neural network, namely, the weights and biases, are represented by fuzzy numbers rather than crisp numbers. Through the application of the extension principle, the fuzzy number representative of the output variable (water level or discharge) is then calculated at each time step on the basis of a set of crisp inputs and fuzzy parameters of the neural network. The proposed neural network thus allows uncertainty to be taken into account at the forecasting stage not providing only deterministic or crisp predictions, but rather predictions in terms of 'the discharge (or level) will fall between two values, indicated according to the level of credibility considered, whereas it will take on a certain value when the level of credibility is maximum'. The fuzzy parameters of the neural network are estimated using a calibration procedure that imposes a constraint whereby for an assigned h-level the envelope of the corresponding intervals representing the outputs (forecasted levels or discharges, calculated at different points in time) must include a prefixed percentage of observed values. The proposed model is applied to two different case studies. Specifically, the data related to the first case study are used to develop and test a flood event-based water level forecasting model, whereas the data related to the latter are used for continuous discharge forecasting. The results obtained are compared with those provided by other data-driven models - Bayesian neural networks (Neal, R.M. 1992, Bayesian training of backpropagation networks by the hybrid Monte Carlo method. Tech. Rep. CRG-TR-92-1, Dep. of Comput. Sci., Univ. of Toronto, Toronto, Ont., Canada.) and the Local Uncertainty Estimation Model (Shrestha D.L. and Solomatine D.P. 2006, Machine learning

  6. Investigation of properties of coal-water slurries produced by electric discharge methods

    NASA Astrophysics Data System (ADS)

    Buyantuev, S.; Khmelev, A.; Kondratenko, A.; Baldynova, F.

    2015-11-01

    The purpose of research is to obtain high quality coal-water slurry with minimum energy consumption. The paper presents the characteristics of coal-water slurries produced by electric discharge methods. The raw material is coal from different mines (Tugnuisky, Aduun- Chulunsky, etc.). Micrographs of the surface of the coal particles in the slurry and its chemical composition are obtained by scanning electron microscopy. Micrographs showed that the electric discharge treatment resulted in a significant dispersion of the coal particles. Elemental analysis showed a significant reduction of oxides of sulfur and nitrogen. Viscosity of slurries was determined by Brookfield rotational viscometer and corresponds to the standard of GB / T18856.4.

  7. Disintegration of rocks based on magnetically isolated high voltage discharge

    NASA Astrophysics Data System (ADS)

    He, Mengbing; Jiang, Jinbo; Huang, Guoliang; Liu, Jun; Li, Chengzu

    2013-02-01

    Recently, a method utilizing pulsed power technology for disintegration of rocks arouses great interest of many researchers. In this paper, an improved method based on magnetic switch and the results shown that the uniform dielectrics like plastic can be broken down in water is presented, and the feasible mechanism explaining the breakdown of solid is proposed and proved experimentally. A high voltage pulse of 120 kV, rise time 0.2 μs was used to ignite the discharging channel in solids. When the plasma channel is formed in the solid, the resistance of the channel is quiet small; even if a relatively low voltage is applied on the channel on this occasion, it will produce high current to heat the plasma channel rapidly, and eventually disintegrate the solids. The feasibility of promising industrial application in the drilling and demolition of natural and artificial solid materials by the method we presented is verified by the experiment result in the paper.

  8. [Desulphurization with multi-needle-water film electrodes by corona discharge].

    PubMed

    Huang, Xu-ran; Li, Guo-feng; Li, Jie; Wu, Yan

    2008-09-01

    The study of this paper adopted stainless steel multi-needle as a high voltage electrode system, and water film as low voltage electrode. The electrodes were supplied with negative DC high voltage. Polluted gas containing sulfur dioxide (SO2) flowed into the corona discharge field from the center of the high voltage electrode system in an axis direction, then get across the water surface. Under the effect of corona discharge plasma and water absorption, SO2 was removed by converting it into sulfuric acid. The effect of the three factors which were the applied voltage, SO2 inlet concentration and duration of the exposure to the corona discharge on desulphurization efficiency has been studied mostly. Moreover, the concentrations of SO3(2-) and SO4(2-) ions in the water were measured and the mechanism of desulphurization was analyzed. The results showed that there was a synergistic effect on the removal of SO2 when combining corona discharge and water absorption, and both the desulphurization efficiency and the amount of sulfuric acid increased evidently. As the applied voltage and the duration increased, the desulphurization efficiency increased. Also, the SO2 inlet concentration had effect on desulphurization efficiency. When the SO2 inlet concentration was 430 x 10(-6), the voltage was 14.5 kV and the duration was 7.5 s, a desulphurization efficiency of more than 90% could be attained. PMID:19068659

  9. High-speed imaging system for observation of discharge phenomena

    NASA Astrophysics Data System (ADS)

    Tanabe, R.; Kusano, H.; Ito, Y.

    2008-11-01

    A thin metal electrode tip instantly changes its shape into a sphere or a needlelike shape in a single electrical discharge of high current. These changes occur within several hundred microseconds. To observe these high-speed phenomena in a single discharge, an imaging system using a high-speed video camera and a high repetition rate pulse laser was constructed. A nanosecond laser, the wavelength of which was 532 nm, was used as the illuminating source of a newly developed high-speed video camera, HPV-1. The time resolution of our system was determined by the laser pulse width and was about 80 nanoseconds. The system can take one hundred pictures at 16- or 64-microsecond intervals in a single discharge event. A band-pass filter at 532 nm was placed in front of the camera to block the emission of the discharge arc at other wavelengths. Therefore, clear images of the electrode were recorded even during the discharge. If the laser was not used, only images of plasma during discharge and thermal radiation from the electrode after discharge were observed. These results demonstrate that the combination of a high repetition rate and a short pulse laser with a high speed video camera provides a unique and powerful method for high speed imaging.

  10. State waste discharge permit application: 400 Area secondary cooling water

    SciTech Connect

    Not Available

    1992-12-01

    This document constitutes the Washington Administrative Code 173-216 State Waste Discharge Permit Application that serves as interim compliance as required by the Consent Order DE 91NM-177, for the 400 Area Secondary Cooling Water stream. As part of the Hanford Federal Facility Agreement and Consent Order negotiations, the US Department of Energy, Richland Operations Office, the US Environmental Protection Agency, and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground on the Hanford Site which affect groundwater or have the potential to affect groundwater would be subject to permitting under the structure of Chapter 173-216 (or 173-218 where applicable) of the Washington Administrative Code, the State Waste Discharge Permitting Program. As a result of this decision, the Washington State Department of Ecology and the US Department of Energy, Richland Operations Office entered in to Consent Order DE 91NM-177. The Consent Order DE 91NM-177 requires a series of permitting activities for liquid effluent discharges.

  11. Electrodeless discharge lamp is easily started, has high stability

    NASA Technical Reports Server (NTRS)

    Bell, W. E.; Bloom, A. L.

    1966-01-01

    Electrodeless discharge borosilicate glass lamp is used in various high-resolution optical systems. It is partially charged with krypton, contains small amounts of rubidium, and is enclosed in a hermetically sealed envelope that maintains the lamp at an optimum temperature during discharge. The lamp is quickly started by its excitation coil.

  12. Approaches to setting organism-based ballast water discharge standards.

    PubMed

    Henry, Lee; Reusser, Deborah A; Frazier, Melanie

    2013-03-01

    As a vector by which foreign species invade coastal and freshwater waterbodies, ballast water discharge from ships is recognized as a major environmental threat. The International Maritime Organization (IMO) drafted an international treaty establishing ballast water discharge standards based on the number of viable organisms per volume of ballast discharge for different organism size classes. Concerns that the IMO standards are not sufficiently protective have initiated several state and national efforts in the United States to develop more stringent standards. We evaluated seven approaches to establishing discharge standards for the > 50-microm size class: (1) expert opinion/management consensus, (2) zero detectable living organisms, (3) natural invasion rates, (4) reaction-diffusion models, (5) population viability analysis (PVA) models, (6) per capita invasion probabilities (PCIP), and (7) experimental studies. Because of the difficulty in synthesizing scientific knowledge in an unbiased and transparent fashion, we recommend the use of quantitative models instead of expert opinion. The actual organism concentration associated with a "zero detectable organisms" standard is defined by the statistical rigor of its monitoring program; thus it is not clear whether such a standard is as stringent as other standards. For several reasons, the natural invasion rate, reaction-diffusion, and experimental approaches are not considered suitable for generating discharge standards. PVA models can be used to predict the likelihood of establishment of introduced species but are limited by a lack of population vital rates for species characteristic of ballast water discharges. Until such rates become available, PVA models are better suited to evaluate relative efficiency of proposed standards rather than predicting probabilities of invasion. The PCIP approach, which is based on historical invasion rates at a regional scale, appears to circumvent many of the indicated problems

  13. Approaches to setting organism-based ballast water discharge standards

    USGS Publications Warehouse

    Lee, Henry, II; Reusser, Deborah A.; Frazier, Melanie

    2013-01-01

    As a vector by which foreign species invade coastal and freshwater waterbodies, ballast water discharge from ships is recognized as a major environmental threat. The International Maritime Organization (IMO) drafted an international treaty establishing ballast water discharge standards based on the number of viable organisms per volume of ballast discharge for different organism size classes. Concerns that the IMO standards are not sufficiently protective have initiated several state and national efforts in the United States to develop more stringent standards. We evaluated seven approaches to establishing discharge standards for the >50-μm size class: (1) expert opinion/management consensus, (2) zero detectable living organisms, (3) natural invasion rates, (4) reaction–diffusion models, (5) population viability analysis (PVA) models, (6) per capita invasion probabilities (PCIP), and (7) experimental studies. Because of the difficulty in synthesizing scientific knowledge in an unbiased and transparent fashion, we recommend the use of quantitative models instead of expert opinion. The actual organism concentration associated with a “zero detectable organisms” standard is defined by the statistical rigor of its monitoring program; thus it is not clear whether such a standard is as stringent as other standards. For several reasons, the natural invasion rate, reaction–diffusion, and experimental approaches are not considered suitable for generating discharge standards. PVA models can be used to predict the likelihood of establishment of introduced species but are limited by a lack of population vital rates for species characteristic of ballast water discharges. Until such rates become available, PVA models are better suited to evaluate relative efficiency of proposed standards rather than predicting probabilities of invasion. The PCIP approach, which is based on historical invasion rates at a regional scale, appears to circumvent many of the indicated problems

  14. Ground water discharge and the related nutrient and trace metal fluxes into Quincy bay, Massachusetts.

    PubMed

    Poppe, L J; Moffett, A M

    1993-03-01

    Measurement of the rate and direction of ground water flow beneath Wollaston Beach, Quincy, Massachusetts by use of a heat-pulsing flowmeter shows a mean velocity in the bulk sediment of 40 cm d(-1). The estimated total discharge of ground water into Quincy Bay during October 1990 was 1324-2177 m(3) d(-1), a relatively low ground water discharge rate. The tides have only a moderate effect on the rate and direction of this flow. Other important controls on the rate and volume of ground water flow are the limited thickness, geographic extent, and permeability of the aquifer. Comparisons of published streamflow data and estimates of ground water discharge indicate that ground water makes up between 7.4-12.1% of the gaged freshwater input into Quincy Bay. The data from this study suggest the ground water discharge is a less important recharge component to Quincy Bay than predicted by National Urban Runoff Program (NURP) models.The high nitrate and low nitrite and ammonia concentrations in the ground water at the backshore well sites and low nitrate and high nitrite and ammonia concentrations in the water flowing from the foreshore suggests that denitrification is active in the sediments. The low ground water flow rates and low nitrate concentrations in the foreshore samples suggest that little or no nitrate is surviving the denitrification process to affect the planktonic community. Similarly, oxidizing conditions in the aquifer and low trace metal concentrations in the ground water samples suggest that the metals may be precipitating and binding to sedimentary phases before impacting the bay. PMID:24227453

  15. Discharging Through an Orifice Determines Steam-Water Enthalpy

    SciTech Connect

    James, Russell

    1987-01-20

    A wide range of steam-water mixtures was discharged to the atmosphere through a 10.7 mm diameter orifice which was sharp-edged with a minuscule throat pressure tapping. The ratio of throat pressure to up-stream pressure was found sensitive to dryness fraction over the whole range studied from 0.03 to 1.0. The technique (employing large orifices) has the potential of identifying the unknown enthalpy of geothermal wells discharging large flows. Contrariwise, a nozzle (rounded entry orifice) was found remarkably _insensitive_ over most of the dryness range and hence is useless for such determinations; however, it can be used to measure the flow-rate when enthalpy is known. 2 figs., 7 refs.

  16. Groundwater and surface water discharge from an abandoned tailings impoundment: Implications for watershed water quality

    NASA Astrophysics Data System (ADS)

    Moncur, M. C.; Ptacek, C. J.; Blowes, D. W.; Birks, S. J.

    2006-12-01

    Release of acid drainage from mine-waste disposal areas is a problem of international scale. Drainage from sulfide-rich waste can result in contaminated surface waters, directly through surface runoff and indirectly, from discharge of contaminated groundwater flow. Camp Lake, located in Northern Manitoba, receives both direct and indirect drainage from an abandoned tailings impoundment, which has severely affected the quality of the downstream watershed. Nearly a century of sulfide oxidation at this mine site has resulted in extremely high concentrations of oxidation products in the surface water and groundwater discharging from the two tailings impoundments, both of which flow into an adjacent semi-isolated shallow bay in Camp Lake. The incorporation of these aqueous effluents has altered the composition of the lake water, which in turn has modified the physical limnology of the lake. The various sources of water and solutes to the lake (surface inflows, perched water table, primary water table) contribute varying concentrations of metals to the overall contaminant loadings to the lake, and can be characterized by distinct 3H, δ18O, and δ2H compositions. Geochemical profiles of the water column indicate that, despite its shallow depth (6 m), the bay is stratified throughout the year. The greatest accumulation of dissolved metals and SO4 is in the lower portion of the water column, with concentrations up to 8500 mg/L Fe, 20,000 mg/L SO4, 30 mg/L Zn, and 100 mg/L Al, including elevated concentrations of Cu, Cd, Pb, and Ni. This stratification is mirrored in the δ18O, δ2H and d-excess profiles within the lake water column, with an evaporatively enriched surface layer overlying the isotopically lighter, higher d-excess hypolimnion. Despite meromictic conditions and very high solute concentrations being limited to the semi-isolated bay, the annual loadings of acid, sulfate, and metals from Camp Lake to the adjacent lake are extremely large, and fluctuate seasonally

  17. Complex utilization of snf processing wastes in air plasma of high-frequency torch discharge

    NASA Astrophysics Data System (ADS)

    Karengin, A. G.; Karengin, A. A.; Podgornaya, O. D.; Shlotgauer, E. E.

    2014-10-01

    We present results of complex spent nuclear fuel wastes utilization process in air plasma of high-frequency torch discharge in form of dispersed water-organic compositions. We demonstrate the possibility to apply magnetic separation for effective extraction of obtained dispersed solid products including magnetic iron oxide from water suspension.

  18. Monitoring Environmental Recovery at Terminated Produced Water Discharge Sites in Coastal Louisiana Waters

    SciTech Connect

    Continental Shelf Associates, Inc.

    1999-08-16

    This report presents the results of a study of terminated produced water discharge sites in the coastal waters of Louisiana. Environmental recovery at the sites is documented by comparing pre-termination and post-termination (six months and one year) data. Produced water, sediments, and sediment interstitial water samples were analyzed for radionuclides, metals, and hydrocarbons. Benthic infauna were identified from samples collected in the vicinity of the discharge and reference sites. Radium isotope activities were determined in fish and crustacean samples. In addition, an environmental risk assessment is made on the basis of the concentrations of metals and hydrocarbons determined in the samples.

  19. Drainage water management effects on tile discharge and water quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nitrogen (N) fluxes from tile drained watersheds have been implicated in water quality studies of the Mississippi River Basin, but the contribution of tile drains to N export in headwater watersheds is not well understood. The objective of this study was to ascertain seasonal and annual contribution...

  20. Plasma Discharges in Gas Bubbles in Liquid Water: Breakdown Mechanisms and Resultant Chemistry

    NASA Astrophysics Data System (ADS)

    Gucker, Sarah M. N.

    The use of atmospheric pressure plasmas in gases and liquids for purification of liquids has been investigated by numerous researchers, and is highly attractive due to their strong potential as a disinfectant and sterilizer. However, the fundamental understanding of plasma production in liquid water is still limited. Despite the decades of study dedicated to electrical discharges in liquids, many physical aspects of liquids, such as the high inhomogeneity of liquids, complicate analyses. For example, the complex nonlinearities of the fluid have intricate effects on the electric field of the propagating streamer. Additionally, the liquid material itself can vaporize, leading to discontinuous liquid-vapor boundaries. Both can and do often lead to notable hydrodynamic effects. The chemistry of these high voltage discharges on liquid media can have circular effects, with the produced species having influence on future discharges. Two notable examples include an increase in liquid conductivity via charged species production, which affects the discharge. A second, more complicated scenario seen in some liquids (such as water) is the doubling or tripling of molecular density for a few molecule layers around a high voltage electrode. These complexities require technological advancements in optical diagnostics that have only recently come into being. This dissertation investigates several aspects of electrical discharges in gas bubbles in liquids. Two primary experimental configurations are investigated: the first allows for single bubble analysis through the use of an acoustic trap. Electrodes may be brought in around the bubble to allow for plasma formation without physically touching the bubble. The second experiment investigates the resulting liquid phase chemistry that is driven by the discharge. This is done through a dielectric barrier discharge with a central high voltage surrounded by a quartz discharge tube with a coil ground electrode on the outside. The plasma

  1. Insulator damage in high current discharges

    NASA Astrophysics Data System (ADS)

    Ranon, P. M.; Kristiansen, M.; Lehr, F. M.; Hatfield, L. L.

    1986-11-01

    The degradation of the hold-off voltage capability of several composite candidates for railgun insulators was studied experimentally. The materials examined were BN, alumina (Coor's ceramic), and two types of laminated fiberglass/epoxy (FGE I and FGE II). Sample 1 cm thick plates of the insulators were inserted into a surface discharge switch (SDS) with a gap of 1.6 in., i.e., an initial hold-off voltage of 40 kV. FGE I retained the hold-off voltage for more than 10,000 shots at a current of 1 kA maximum, but degraded significantly after 50 shots at currents over 200 kA. BN shattered when the repetition rate exceeded 1 pulse/sec.

  2. Partial discharge in a high voltage experimental test assembly

    SciTech Connect

    Koss, R.J.; Brainard, J.P.

    1998-07-01

    This study was initiated when a new type of breakdown occurred in a high voltage experimental test assembly. An anomalous current pulse was observed, which indicated partial discharges, some leading to total breakdowns. High voltage insulator defects are shown along with their effect on the electrostatic fields in the breakdown region. OPERA electromagnetic field modeling software is used to calculate the fields and present a cause for the discharge. Several design modifications are investigated and one of the simplest resulted in a 25% decrease in the field at the discharge surface.

  3. Analytical approach for predicting fresh water discharge in an estuary based on tidal water level observations

    NASA Astrophysics Data System (ADS)

    Cai, H.; Savenije, H. H. G.; Jiang, C.

    2014-06-01

    As the tidal wave propagates into an estuary, the tidally averaged water level tends to rise in landward direction due to the density difference between saline and fresh water and the asymmetry of the friction. The effect of friction on the residual slope is even more remarkable when accounting for fresh water discharge. In this study, we investigate the influence of river discharge on tidal wave propagation in the Yangtze estuary with specific attention to residual water level slope. This is done by using a one-dimensional analytical model for tidal hydrodynamics accounting for the residual water level. We demonstrate the importance of the residual slope on tidal dynamics and use it to improve the prediction of the tidal propagation in estuaries (i.e., tidal damping, velocity amplitude, wave celerity and phase lag), especially when the influence of river discharge is significant. Finally, we develop a new inverse analytical approach for estimating fresh water discharge on the basis of tidal water level observations along the estuary, which can be used as a tool to obtain information on the river discharge that is otherwise difficult to measure in the tidal region.

  4. Analytical approach for predicting fresh water discharge in an estuary based on tidal water level observations

    NASA Astrophysics Data System (ADS)

    Cai, H.; Savenije, H. H. G.; Jiang, C.

    2014-10-01

    As the tidal wave propagates into an estuary, the tidally averaged water level tends to rise in landward direction due to the density difference between saline and fresh water and the asymmetry of the friction. The effect of friction on the residual slope is even more remarkable when accounting for fresh water discharge. In this study, we investigate the influence of river discharge on tidal wave propagation in the Yangtze estuary with specific attention to residual water level slope. This is done by using a one-dimensional analytical model for tidal hydrodynamics accounting for the residual water level. We demonstrate the importance of the residual slope on tidal dynamics and use it to improve the prediction of the tidal propagation in estuaries (i.e. tidal damping, velocity amplitude, wave celerity and phase lag), especially when the influence of river discharge is significant. Finally, we develop a new inverse analytical approach for estimating fresh water discharge on the basis of tidal water level observations along the estuary, which can be used as a tool to obtain information on the river discharge that is otherwise difficult to measure in the tidal region.

  5. High ozone values near ground caused by silent discharge

    NASA Astrophysics Data System (ADS)

    Duetsch, H. U.; Graber, W.; Wyss, A.

    Continuous ozone monitoring near the top of a 120 m high idle smoke stack had shown a very frequent occurrence of mixing ratios suggesting air of stratospheric origin. In order to investigate whether these events could instead have been due to ozone production by silent discharge in the locally very strong electric field, an experiment was designed which measured point discharge current close to the intake and ozone at the same level using an electrically shielded intake. This second sensor did not show the high ozone values of the first and there was a high correlation between point discharge current above a certain threshold and unusual ozone peaks. Silent discharge was thus in almost all the cases responsible for the high ozone peaks at this site.

  6. Discharge characteristics of a high speed fuel injection system

    NASA Technical Reports Server (NTRS)

    Matthews, Robertson

    1925-01-01

    Discussed here are some discharge characteristics of a fuel injection system intended primarily for high speed service. The system consisted of a cam actuated fuel pump, a spring loaded automatic injection valve, and a connecting tube.

  7. Dynamics of laser-guided alternating current high voltage discharges

    NASA Astrophysics Data System (ADS)

    Daigle, J.-F.; Théberge, F.; Lassonde, P.; Kieffer, J.-C.; Fujii, T.; Fortin, J.; Châteauneuf, M.; Dubois, J.

    2013-10-01

    The dynamics of laser-guided alternating current high voltage discharges are characterized using a streak camera. Laser filaments were used to trigger and guide the discharges produced by a commercial Tesla coil. The streaking images revealed that the dynamics of the guided alternating current high voltage corona are different from that of a direct current source. The measured effective corona velocity and the absence of leader streamers confirmed that it evolves in a pure leader regime.

  8. Subsurface storage of freshwater in south Florida; evaluation of surface-water discharge data at selected sites

    USGS Publications Warehouse

    Sonntag, W.H.

    1984-01-01

    Canal discharge in south Florida may consist of a potential source of freshwater for deep-well injection. Discharge data for the 1970-81 water years at 27 canal and river sites were analyzed. Flow was analyzed for 30-, 60-, 90-, 120-, and 183-consecutive-day low-mean discharges during the periods of highest flow to define minimum high-flow-period fresh surface-water discharges at the 27 sites. Curves show the magnitude and frequency of average minimum flows for consecutive-day periods during high-flow periods, and duration curves and tables show the percentage of time that selected discharges were equaled or exceeded. Canal discharge as high as 660 cubic feet per second occurred 70 percent of the time during the high-flow period at one site (Tamiami Canal Outlets, Levee 67A to 40-Mile Bend). At 11 sites, discharges of 110 to 370 cubic feet per second occurred 70 percent of the high-flow periods, while at 9 sites, discharges of 21 to 100 cubic feet per second occurred 70 percent of the time during the high-flow periods. At other sites (those in the Biscayne, Plantation Road, Middle River, C-111, and Cypress Creek Canals), discharges as low as 0.1 cubic foot per second occurred 70 percent of the time during the high-flow periods. Criteria for amounts of surplus freshwater considered adequate to support injection systems cannot be established, as they would vary greatly with water needs to be satisfied and with the efficiency of a particular injection system. However, based upon this analysis of discharge at 27 canal and river sites throughout south Florida, it appears that substantial amounts of water are available for surface injection and storage. (USGS)

  9. The Time Evolution of Streamer Discharges in Single and Multiple Bubbles in Water

    NASA Astrophysics Data System (ADS)

    Mujovic, Selman; Groele, Joseph; Foster, John

    2015-09-01

    The interaction of plasma with liquid water lies at the heart of a variety of revisited technological applications ranging from water treatment to wound healing. Plasma ignition and propagation in water, however, is poorly understood. It has been theorized that plasma streamer propagation takes place in microbubbles, namely streamer bubble hopping. In this work, discharge development in single and multiple bubble acoustic systems is investigated using high-speed imaging and emission spectroscopy. Optical filters allow for time resolved measurements of specific chemical species as well. Better understanding of these breakdown processes will guide the construction of an effective plasma water purifier. NSF CBET 1336375.

  10. Estimated ground-water discharge by evapotranspiration from Death Valley, California, 1997-2001

    USGS Publications Warehouse

    DeMeo, Guy A.; Laczniak, Randell J.; Boyd, Robert A.; Smith, J. LaRue; Nylund, Walter E.

    2003-01-01

    The U.S. Geological Survey, in cooperation with the National Park Service and Inyo County, Calif., collected field data from 1997 through 2001 to accurately estimate the amount of annual ground-water discharge by evapotranspiration (ET) from the floor of Death Valley, California. Multispectral satellite-imagery and National Wetlands Inventory data are used to delineate evaporative ground-water discharge areas on the Death Valley floor. These areas are divided into five general units where ground-water discharge from ET is considered to be significant. Based upon similarities in soil type, soil moisture, vegetation type, and vegetation density; the ET units are salt-encrusted playa (21,287 acres), bare-soil playa (75,922 acres), low-density vegetation (6,625 acres), moderate-density vegetation (5,019 acres), and high-density vegetation (1,522 acres). Annual ET was computed for ET units with micrometeorological data which were continuously measured at six instrumented sites. Total ET was determined at sites that were chosen for their soil- and vegetated-surface conditions, which include salt-encrusted playa (extensive salt encrustation) 0.17 feet per year, bare-soil playa (silt and salt encrustation) 0.21 feet per year, pickleweed (pickleweed plants, low-density vegetation) 0.60 feet per year, Eagle Borax (arrowweed plants and salt grass, moderate-density vegetation) 1.99 feet per year, Mesquite Flat (mesquite trees, high-density vegetation) 2.86 feet per year, and Mesquite Flat mixed grasses (mixed meadow grasses, high-density vegetation) 3.90 feet per year. Precipitation, flooding, and ground-water discharge satisfy ET demand in Death Valley. Ground-water discharge is estimated by deducting local precipitation and flooding from cumulative ET estimates. Discharge rates from ET units were not estimated directly because the range of vegetation units far exceeded the five specific vegetation units that were measured. The rate of annual ground-water discharge by ET for

  11. Zero-discharge: An application of process water recovery technology in the food processing industry

    SciTech Connect

    Fok, S.; Moore, B.

    1999-07-01

    Water is a valuable natural resource and the food processing industry has been among the leading industrial water users in California. With support from a major northern California utility and the California Institute for Food and Agricultural Research, Tri Valley Growers (TVG) has successfully installed the first US energy-efficient zero-discharge process water reclamation system at its Oberti Olive processing facility in Madera, California. The advanced zero-discharge system is the largest application in the world of membrane filtration for recovering water from a food processing plant. Previously, the plant discharged an average of 1 million gallons of salty wastewater (brine) a day into 160 acres of evaporation ponds. However, new environmental regulations made the ponds obsolete. The cost of process water disposal using alternate biotreatment system was prohibitive and would make continued operation uneconomical with plant closure and job loss the likely outcome. Through comprehensive pilot testing and subsequent system design and operational optimization, the advance membrane filtration system with pre- and post-treatment now recovers about 80% of the process liquid in high priority form of water for subsequent reuse at the plant. The solids produced in olive processing, plus concentrated process liquids are used off-site as an animal feed component, thus achieving the plant zero-discharge scheme. The successful implementation of the zero discharge system at the Oberti Olive processing plant has produced energy saving of 3,500,000 kilowatthours and 244,000 therms of gas a year of power as compared to the alternate biotreatment system. It also prevented plant closure and job loss. In addition, water conservation and the discontinuation of evaporation pond use is beneficial to the environment. The project was applauded by the California Environmental Protection Agency as a positive step forward for environmental technology in the agricultural sector in

  12. Water Treatment using Discharge Generated in Cavitation Field with Micro Bubble Cloud

    NASA Astrophysics Data System (ADS)

    Ihara, Satoshi; Hirohata, Taiki; Kominato, Yuichi; Yamabe, Chobei; Ike, Hideaki; Hakiai, Kazunori; Hirabayashi, Kazuya; Tamagawa, Masaaki

    New method of water treatment for wastewater using discharge in water cavitation field, in which numerous micro bubbles were generated by high-speed water flow, was proposed in this paper. Indigo carmine solution, which is a type of dye, with a concentration of 9mg/Liter was used as a specimen for demonstration of water treatment. The total volume of solution and average speed of solution in the cavitation field was 20 Liter and about 7.4 m/s, respectively. A reduction ratio of absorbance of 96% was obtained in 50 min of treatment time at an electrode distance of 2 mm and a discharge power of 16 W. Also it was found that the efficiency of decolorization was improved by changing the electrode location.

  13. Sterilization of Fungus in Water by Pulsed Power Gas Discharge Reactor Spraying Water Droplets for Water Treatment

    NASA Astrophysics Data System (ADS)

    Saito, Tsukasa; Handa, Taiki; Minamitani, Yasushi

    We study sterilization of bacteria in water using pulsed streamer discharge of gas phase. This method enhances efficiency of water treatment by spraying pretreatment water in a streamer discharge area. In this paper, yeast was sterilized because we assumed a case that fungus like mold existed in wastewater. As a result, colony forming units decreased rapidly for 2 minutes of the processing time, and all yeast sterilized by 45 minutes of the processing time.

  14. OH Radical and a Drizzling Water Jet Production from the Ball-Lightning Discharge in Water

    NASA Astrophysics Data System (ADS)

    Maeyama, Mitsuaki; Tanaka, Yasutomo

    The ball lightning, or fireball discharge using the typical electrode configuration was reported to produce a long-living spherical plasmoid with radius exceed 10 cm at atmospheric pressure. In this study, we investigated the relationship between a optical output emitted from OH radicals and discharge conditions of the ball-lightning electrode configuration, and discussed its possibility to the water treatment process. As a results, in both polarity cases of the charged voltage V0, a ball-lightning discharge and the optical emission from OH radicals as a major radiation can be generated on the condition |V0| > 4 kV in tap water. Furthermore, an intensive upward water jet from the rod electrode is observed in case of positive polarity and in 0.2% NaCl solution, which is composed of drizzling water drops near the rod electrode.

  15. Characteristics of streamer discharge development between the dielectric-coated sphere-plane electrodes in water

    SciTech Connect

    Zhu Taiyun; Yang Lanjun; Jia Zhijie; Zhang Qiaogen

    2008-12-01

    This paper presents the characteristics of the streamer discharge development between the dielectric-coated sphere-plane electrodes in water. In order to study the streamer propagation mechanism, the factors such as polarities, water conductivity, and ambient pressure were taken into consideration. Experimental results demonstrate that the water conductivity and amplitude of applied voltage both have a great influence on mean velocity and brightness of the streamer. When the ambient pressure decreases from 0.1 to 0.0065 MPa, the pressure has little influence on the mean velocities of the streamer in both distilled and tap water for fast streamer. The existence of dielectric coating causes a lower initiation voltage of the streamer for negative polarity than that for positive one. Also, the 10% breakdown voltage (U{sub 10%}) is decreased by 20% under the pressure of 0.0065 MPa than that under the pressure of 0.1 MPa in distilled water, while the U{sub 10%} is almost the same under different pressures in tap water. Based on the analysis of the discharge images and current waveforms as well as the above experimental results, it can be concluded that the streamer propagation is composed of the generation of the microbubbles and the discharge in the bubbles. For subsonic streamer, the generation of the bubbles is more likely a thermal process, whereas for supersonic streamer, the ionization and dissociation of water molecules in high electric field are involved in the bubble generation process.

  16. Estimating water quality using linear mixed models with stream discharge and turbidity

    NASA Astrophysics Data System (ADS)

    Lessels, J. S.; Bishop, T. F. A.

    2013-08-01

    Most water quality monitoring schemes rely on estimation methods as it is often far too expensive to monitor water quality properties continuously. Estimations are used to evaluate management strategies and long term trends. It is critical that the estimation methods provide accurate estimations and an accurate estimate of the associated uncertainty. Currently the most common estimation methods assume observations are sampled using a probabilistic sampling scheme, however this assumption is often not met. This paper evaluated the ability of a linear mixed model to estimate water quality concentration values based on observations collected using non-probabilistic sampling. The linear mixed models were used to predict total phosphorus and total nitrogen observations from two catchments in south east Australia. A comparison between stream discharge and turbidity as predictors is made to investigate the effectiveness of turbidity to estimate water quality. In addition to stream discharge and turbidity, several covariates were derived from stream discharge in an attempt to account for hydrological processes. To compare models and their covariates leave one out event cross validation was performed. Event cross validation evaluated predictions during periods of high stream discharge. The inclusion of temporal auto-correlation component improved the accuracy of all models for total phosphorus and total nitrogen. For both catchments the use of turbidity instead of stream discharge increased the accuracy of predictions by at least 15% for total phosphorus and total nitrogen. However, event based cross validation indicated that a combination of both turbidity and stream discharge based variables provided more accurate predictions, decreasing the event RMSE by 18% for total phosphorus and 24% for total nitrogen. In catchments characterised by long periods of base-flow and short rainfall events the addition of turbidity measurements provide more accurate predictions during base

  17. Micro electrical discharge drilling of tungsten carbide using deionized water

    NASA Astrophysics Data System (ADS)

    Song, Ki Young; Chung, Do Kwan; Park, Min Soo; Chu, Chong Nam

    2009-04-01

    Micro electrical discharge machining (micro EDM) is an effective machining method for cobalt-bonded tungsten carbide (WC-Co); however, this material is susceptible to electrolytic corrosion when deionized water is used as the working fluid with a dc power source for the RC circuit. In this study, a bipolar pulse power source and a triangular electrode were used in order to reduce the electrolytic corrosion phenomenon during micro EDM using an RC discharge circuit. A bipolar pulse power source reduces the positive polarity period of the workpiece by periodically alternating the polarity of the workpiece and electrode and decreases the average gap voltage at the machining gap. Therefore, electrolytic corrosion, which is a type of electrochemical reaction on the positively charged workpiece, is reduced by these electrical conditions. The triangular electrode has a smaller side area as compared with the cylindrical electrode. Since the electrolytic corrosion is an electrochemical reaction between the side of the electrode and the surface of the workpiece, the small side area of the triangular electrode could reduce these reactions. With the aid of the bipolar pulse power source and the triangular electrode, an electrolytic-corrosion-free hole could be machined on the WC-Co workpiece using deionized water.

  18. 77 FR 55417 - Standards for Living Organisms in Ships' Ballast Water Discharged in U.S. Waters

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-10

    ... Organisms in Ships' Ballast Water Discharged in U.S. Waters (BWDS) Final Rule (77 FR 35268). The rulemaking... (77 FR 17254). The Coast Guard is now publishing a document to advise the public that we received four...' Ballast Water Discharged in U.S. Waters AGENCY: Coast Guard, DHS. ACTION: Rule; information...

  19. Glow discharge techniques for conditioning high vacuum systems

    SciTech Connect

    Dylla, H.F.

    1988-03-01

    A review is given of glow discharge techniques which are useful for conditioning vacuum vessels for high vacuum applications. Substantial development of glow discharge techniques has been done for the purpose of in-situ conditioning of the large ultrahigh vacuum systems for particle accelerators and magnetic fusion devices. In these applications the glow discharge treatments remove impurities from vessel surfaces in order to minimize particle-induced desorption coefficients. Cleaning mechanisms involve a mixture of sputtering and ion- (or neutral) induced desorption effects depending on the gas mixture (ArO/sub 2/ vs. H/sub 2/) and excitation method (DC, RF, and ECR). The author will review the methodology of glow discharge conditioning, diagnostic measurements provided by residual gas and surface composition analysis, and applications to vessel conditioning and materials processing. 76 refs., 16 figs.

  20. Removal of NO and SO2 in Corona Discharge Plasma Reactor with Water Film

    NASA Astrophysics Data System (ADS)

    He, Yuanji; Dong, Liming; Yang, Jiaxiang

    2004-04-01

    In this paper, a novel type of a corona discharge plasma reactor was designed, which consists of needle-plate-combined electrodes, in which a series of needle electrodes are placed in a glass container filled with flue gas, and a plate electrode is immersed in the water. Based on this model, the removal of NO and SO2 was tested experimentally. In addition, the effect of streamer polarity on the reduction of SO2 and NO was investigated in detail. The experimental results show that the corona wind formed between the high-voltage needle electrode and the water by corona discharge enhances the cleaning efficiency of the flue gas because of the presence of water, and the cleaning efficiency will increase with the increase of applied dc voltage within a definite range. The removal efficiency of SO2 up to 98%, and about 85% of NOx removal under suitable conditions is obtained in our experiments.

  1. Disintegration of rocks based on magnetically isolated high voltage discharge.

    PubMed

    He, Mengbing; Jiang, Jinbo; Huang, Guoliang; Liu, Jun; Li, Chengzu

    2013-02-01

    Recently, a method utilizing pulsed power technology for disintegration of rocks arouses great interest of many researchers. In this paper, an improved method based on magnetic switch and the results shown that the uniform dielectrics like plastic can be broken down in water is presented, and the feasible mechanism explaining the breakdown of solid is proposed and proved experimentally. A high voltage pulse of 120 kV, rise time 0.2 μs was used to ignite the discharging channel in solids. When the plasma channel is formed in the solid, the resistance of the channel is quiet small; even if a relatively low voltage is applied on the channel on this occasion, it will produce high current to heat the plasma channel rapidly, and eventually disintegrate the solids. The feasibility of promising industrial application in the drilling and demolition of natural and artificial solid materials by the method we presented is verified by the experiment result in the paper. PMID:23464235

  2. Hundreds of automatic drip counters reveal infiltration water discharge characteristics in Australian caves

    NASA Astrophysics Data System (ADS)

    Baker, A.; Treble, P. C.; Coleborn, K.; Mahmud, K.; Markowska, M.; Flemons, I.

    2015-12-01

    Quantifying the timing and character of cave drip water discharge is crucial for our understanding of speleothem climate proxies. Since 2010, we have established a long-term, national monitoring program of drip water infiltration onto cave stalagmites using automated Stalagmate© loggers. Five karst regions, from semi-arid to sub-tropical climates, have been instrumented. Over 200 loggers (between 10 and 40 per cave) have collected data on the timing and amount of drip water infiltration, from sites of contrasting limestone geology. Here, we present results demonstrating the timing and characteristics of drip water discharge from 2010 to present. At the semi-arid Cathedral Cave, with a range of depths from 0-40 m, there is a decreasing frequency of recharge events with depth below ground surface. High-intensity, long-duration rainfall events are confirmed to be the primary driver of infiltration events at semi-arid sites, whereas annual rainfall amount is the primary driver at a Mediterranean climate site with high primary porosity. Inter-annual variability in the frequency and relative amount of drip water infiltration is compared to climate forcing variables such as the ENSO and surface temperature. Our cave observatory system helps improve our understanding of the drip water recharge process, drip-water related speleothem proxy records, and provides a baseline monitoring network for diffuse groundwater recharge during a period of climate change.

  3. Meteorological, stream-discharge, and water-quality data for water year 1992 from two basins in Central Nevada

    SciTech Connect

    McKinley, P.W.; Oliver, T.A.

    1995-05-01

    The US Geological Survey, in cooperation with the US Department of Energy, is studying Yucca Mountain, Nevada, as a potential repository for high level nuclear waste. As part of the Yucca Mountain Site Project, the analog recharge study is providing data for the evaluation of recharge to the Yucca Mountain ground-water system given a cooler and wetter climate than currently exists. The current and climatic conditions are favorable to the isolation of radioactive waste. Because waste isolation from the accessible environment for 10,000 years is necessary, climatic change and the potential for increased ground-water recharge need to be considered as part of the characterization of the potential repository. Therefore, two small basins, measuring less than 2 square miles, were studied to determine the volume of precipitation available for recharge to ground water. The semiarid 3-Springs Basin is located to the east of Kawich Peak in the Kawich Range east of Tonopah, Nevada. Stewart Basin is a subalpine drainage basin north of Arc Dome in the Toiyabe Range north of Tonopah, Nevada. The purpose of this publication is to make available the meteorological, stream-discharge, and water-quality data collected during the study. Meteorological data collected include air temperature, soil temperature, solar radiation, and relative humidity. Stream-discharge data were collected from the surface-water outlet of each basin. Water-quality data are chemical analyses of water samples collected from surface- and ground-water sources. Each basin has a meteorological station located in the lower and upper reaches of the basin. Hydrologic records include stream-discharge and water-quality data from the lower meteorological site and water-quality data from springs within the basins.

  4. Electrochemical cell with high discharge/charge rate capability

    DOEpatents

    Redey, Laszlo

    1988-01-01

    A fully charged positive electrode composition for an electrochemical cell includes FeS.sub.2 and NiS.sub.2 in about equal molar amounts along with about 2-20 mole percent of the reaction product Li.sub.2 S. Through selection of appropriate electrolyte compositions, high power output or low operating temperatures can be obtained. The cell includes a substantially constant electrode impedance through most of its charge and discharge range. Exceptionally high discharge rates and overcharge protection are obtainable through use of the inventive electrode composition.

  5. Influence of pulse width on decolorization efficiency of organic dye by discharge inside bubble in water

    NASA Astrophysics Data System (ADS)

    Kawano, S.; Wada, K.; Kakuta, T.; Takaki, K.; Satta, N.; Takahashi, K.

    2013-06-01

    Decolorization of an organic dye by discharge in high conductive water using a pulsed power generator and a discharge reactor was investigated. The discharge reactor consisted of a glass tube and a tungsten wire inserted into the glass tube, which was immersed in the water. Room air was injected into the glass tube to generate bubbles in the water. High voltage pulses were generated by an inductive-energy storage system using semiconductor opening switch (SOS) and by a magnetic pulse compression circuit. Fast recovery diodes were used as SOS diode in the inductive-energy storage system. The pulse width was changed in range from 10 to 1200 ns. The high voltage was applied to the tungsten wire. Indigo carmine was employed as a specimen to evaluate decolorization efficiency. Potassium nitrate was used to adjust the solution conductivity. The dye solution was successfully decolorized at 7 mS/cm conductivity. Energy efficiency for decolorization increased from 0.680 to 55.6 mg/Wh with decreasing the pulse width from 1200 to 10 ns owing to the reduction of ohmic loss.

  6. Density Matters: Review of Approaches to Setting Organism-Based Ballast Water Discharge Standards

    EPA Science Inventory

    As part of their effort to develop national ballast water discharge standards under NPDES permitting, the Office of Water requested that WED scientists identify and review existing approaches to generating organism-based discharge standards for ballast water. Six potential appro...

  7. Emission spectroscopy of a microhollow cathode discharge plasma in helium-water gas mixtures

    SciTech Connect

    Namba, S.; Yamasaki, T.; Hane, Y.; Fukuhara, D.; Kozue, K.; Takiyama, K.

    2011-10-01

    A dc microhollow cathode discharge (MHCD) plasma was generated inflowing helium gas containing water vapor. The cathode hole diameters were 0.3, 0.7, 1.0, and 2.0 mm, each with a length of 2.0 mm. Emission spectroscopy was carried out to investigate the discharge mode and to determine the plasma parameters. For the 0.3-mm cathode, stable MHCDs in an abnormal glow mode existed at pressures up to 100 kPa, whereas for larger diameters, a plasma was not generated at atmospheric pressure. An analysis of the lineshapes relevant to He at 667.8 nm and to H{alpha} at 656.3 nm implied an electron density and gas temperature of 2 x 10{sup 14} cm{sup -3} and 1100 K, respectively, for a 100-kPa discharge in the negative glow region. The dependence of the OH band, and H{alpha} intensities on the discharge current exhibited different behaviors. Specifically, the OH spectrum had a maximum intensity at a certain current, while the H atom intensity kept increasing with the discharge current. This observation implies that a high concentration of OH radicals results in quenching, leading to the production of H atoms via the reaction OH + e{sup -}{yields} O + H + e{sup -}.

  8. Water discharge affects Atlantic salmon Salmo salar smolt production: a 27 year study in the River Orkla, Norway.

    PubMed

    Hvidsten, N A; Diserud, O H; Jensen, A J; Jensås, J G; Johnsen, B O; Ugedal, O

    2015-01-01

    A model that explains 48% of the annual variation in Atlantic salmon Salmo salar smolt production in the River Orkla, Norway, has been established. This variation could be explained by egg deposition, minimum daily discharge during the previous winter and minimum weekly discharge during the summer 3 years before smolt migration. All coefficients in the model were positive, which indicates that more eggs and higher minimum discharge levels during the winter before smolt migration and the summer after hatching benefit smolt production. Hence, when the spawning target of the river is reached, the minimum levels of river discharge, in both winter and summer, are the main bottlenecks for the parr survival, and hence for smolt production. The River Orkla was developed for hydropower production in the early 1980s by the construction of four reservoirs upstream of the river stretch accessible to S. salar. Although no water has been removed from the catchment, the dynamics of water flow has been altered, mainly by increasing discharges during winter and reducing spring floods. In spite of the higher than natural winter discharges, minimum winter discharge is still a determinant of smolt production. Hence, in regulated rivers, the maintenance of discharges to ensure that they are as high as possible during dry periods is an important means of securing high S. salar smolt production. PMID:25418585

  9. ARSENIC CYCLING WITHIN THE WATER COLUMN OF A SMALL LAKE RECEIVING CONTAMINATED GROUND WATER DISCHARGE

    EPA Science Inventory

    The fate of arsenic discharged from contaminated ground water to a small, shallow lake at a hazardous waste site is controlled, in part, by the rate of ferrous iron oxidation-precipitation and arsenic sorption occurring near the lake chemocline. Laboratory experiments were condu...

  10. Fate and effects of produced water discharges in nearshore marine water

    SciTech Connect

    Not Available

    1989-01-01

    The report details the results of studies of chemical and physical properties of the sediments around four platforms in the Gulf of Mexico, with intensive study of two of the areas, and comparison with the produced water discharges from the platforms.

  11. Delineation of biological impact and recovery of selected produced water discharges in inshore Louisiana

    SciTech Connect

    Mulino, M.M.; Rayle, M.F.; Francis, J.C.

    1995-12-01

    The benthos data presented are the results of sampling areas around the Delacroix Island Tank Battery No. 1 produced water discharge prior to and after termination. Data show recovery of the numbers of species and individuals at the discharge site six months after the termination of the discharge.

  12. High-beta discharges in the DIII-D tokamak

    SciTech Connect

    Ferron, J.R.; Chu, M.S.; Helton, F.J.; Howl, W.; Kellman, A.G.; Lao, L.L.; Lazarus, E.A.; Lee, J.K.; Osborne, T.H.; Strait, E.J.; Taylor, T.S.; Turnbull, A.D. )

    1990-06-01

    Low-{ital q} ({ital q}{sub 95}{lt}3) double-null divertor discharges with values of the volume-average toroidal beta as high as 9.3% have been operated in the DIII-D tokamak (Fusion Technol. {bold 8}, 441 (1985)). In discharges with {ital q}{sub 95}{approx}5, values of {beta}{sub {ital T}}/({ital I}/{ital aB}) as high as 5 have been obtained. These discharges are shown to be at or below the stability limit to the value of beta for infinite-{ital n}, ideal ballooning modes. The discharges are significantly below the beta limit for ideal,low toroidal mode number kink modes. The kink mode beta limit is shown to be strongly dependent on the radial profiles of plasma pressure and current. The theoretical beta limit in DIII-D is shown to be in the range {beta}{sub {ital T}}/({ital I}/{ital aB})=4 --5 depending on the value of {ital I}/{ital aB}, and this is consistent with the experiment. High-beta discharges have been operated with ion temperature up to 17 keV. Steady-state, high-beta, low-{ital q} operation is demonstrated by a discharge with {ital I}/{ital aB}=2.6, {ital q}{sub 95}=2.7, in which {beta}{sub {ital T}}{gt}7% is maintained for 1.5 sec.

  13. Obtaining molecular hydrogen in electric discharge of the tornado type in air mixture with ethanol and water vapors

    NASA Astrophysics Data System (ADS)

    Levko, D. S.; Shchedrin, A. I.; Chernyak, V. Ya.; Ol'Shevskiĭ, S. V.; Nedybalyuk, O. A.

    2010-11-01

    A new plasmachemical reactor is proposed that provides a high yield of hydrogen from electric discharge in a mixture of air with ethanol and water vapors. It is shown that intense electron-molecule reactions and high temperature in the discharge region favor an increase in the degree of H2O and C2H5OH conversion into molecular hydrogen. A mechanism of the initiation of chain reactions leading to H2 formation is determined. It is established that H2 concentration reaches saturation in the region of discharge currents above 200 mA.

  14. Cathode degradation and erosion in high pressure arc discharges

    NASA Technical Reports Server (NTRS)

    Hardy, T. L.; Nakanishi, S.

    1983-01-01

    The various processes which control cathode erosion and degradation were identified and evaluated. A direct current arc discharge was established between electrodes in a pressure-controlled gas flow environment. The cathode holder was designed for easy testing of various cathode materials. The anode was a water cooled copper collector electrode. The arc was powered by a dc power supply with current and voltage regulated cross-over control. Nitrogen and argon were used as propellants and the materials used were two percent thoriated tungsten, barium oxide impregnated porous tungsten, pure tungsten and lanthanum hexaboride. The configurations used were cylindrical solid rods, wire bundles supported by hollow molybdenum tubes, cylindrical hollow tubes, and hollow cathodes of the type used in ion thrusters. The results of the mass loss tests in nitrogen indicated that pure tungsten eroded at a rate more than 10 times faster than the rates of the impregnated tungsten materials. It was found that oxygen impurities of less than 0.5 percent in the nitrogen increased the mass loss rate by a factor of 4 over high purity nitrogen. At power levels less than 1 kW, cathode size and current level did not significantly affect the mass loss rate. The hollow cathode was found to be operable in argon and in nitrogen only at pressures below 400 and 200 torr, respectively.

  15. Cathode degradation and erosion in high pressure arc discharges

    NASA Technical Reports Server (NTRS)

    Hardy, T. L.; Nakanishi, S.

    1984-01-01

    The various processes which control cathode erosion and degradation were identified and evaluated. A direct current arc discharge was established between electrodes in a pressure-controlled gas flow environment. The cathode holder was designed for easy testing of various cathode materials. The anode was a water cooled copper collector electrode. The arc was powered by a dc power supply with current and voltage regulated cross-over control. Nitrogen and argon were used as propellants and the materials used were two percent thoriated tungsten, barium oxide impregnated porous tungsten, pure tungsten and lanthanum hexaboride. The configurations used were cylindrical solid rods, wire bundles supported by hollow molybdenum tubes, cylindrical hollow tubes, and hollow cathodes of the type used in ion thrusters. The results of the mass loss tests in nitrogen indicated that pure tungsten eroded at a rate more than 10 times faster than the rates of the impregnated tungsten materials. It was found that oxygen impurities of less than 0.5 percent in the nitrogen increased the mass loss rate by a factor of 4 over high purity nitrogen. At power levels less than 1 kW, cathode size and current level did not significantly affect the mass loss rate. The hollow cathode was found to be operable in argon and in nitrogen only at pressures below 400 and 200 torr, respectively.

  16. Pulsed Discharge Helium Ionization Detector for Highly Sensitive Aquametry.

    PubMed

    Mowry, Curtis D; Pimentel, Adam S; Sparks, Elizabeth S; Moorman, Matthew W; Achyuthan, Komandoor E; Manginell, Ronald P

    2016-01-01

    Trace moisture quantitation is crucial in medical, civilian and military applications. Current aquametry technologies are limited by the sample volume, reactivity, or interferences, and/or instrument size, weight, power, cost, and complexity. We report for the first time on the use of a pulsed discharge helium ionization detector (PDHID-D2) (∼196 cm(3)) for the sensitive (limit of detection, 0.047 ng; 26 ppm), linear (r(2) >0.99), and rapid (< 2 min) quantitation of water using a small (0.2 - 5.0 μL) volume of liquid or gas. The relative humidity sensitivity was 0.22% (61.4 ppmv) with a limit of detection of less than 1 ng moisture with gaseous samples. The sensitivity was 10 to 100 to fold superior to competing technologies without the disadvantages inherent to these technologies. The PDHID-D2, due to its small footprint and low power requirement, has good size, weight, and power-portability (SWAPP) factors. The relatively low cost (∼$5000) and commercial availability of the PDHID-D2 makes our technique applicable to highly sensitive aquametry. PMID:26860562

  17. Submarine Ground-Water Discharge and Its Influence on the Greater Jakarta Bay Ecosystems

    NASA Astrophysics Data System (ADS)

    Lubis, R. F.; Delinom, R.; Bakti, H.; Taniguchi, M.

    2013-12-01

    Jakarta Bay and Kepulauan Seribu (Thousand islands) essentially form a large coastal ecosystem with relatively different characteristics. The whole ecosystem, which is called Greater Jakarta Bay Ecosystem stretches from 106o 20' and 107o 03' east longitude, and from 5o10' to 6o10' south latitude, and is administratively within three provinces. The greater Jakarta bay is mainly influenced by land-based activities. The bay is exposed to high pollution load transported and increase of nutrient loading in from up-land region by 13 rivers and submarine groundwater discharge (SGD). SGD defined as all direct discharge of subsurface fluids in to coastal zone. Components of SGD consist of fresh submarine groundwater discharge and the recirculated saline seawater discharge. SGD is as pathway for the transport of anthropogenic contaminants and nutrients to coastal waters. SGD has recently been recognized as a ubiquitous phenomenon that can strongly influence coastal-water and geochemical budgets and drive ecosystem change. This paper reported that SGD was defined and can be measured. It is likely that the threat from anthropogenic sources is greater than that of natural sources; hence the human activities will continue to dominate the fate of the greater Jakarta Bay ecosystem in the next few decades.Keywords

  18. Arc discharge-mediated disassembly of viral particles in water.

    PubMed

    Lee, Eun-Jung; Lee, Wooseong; Kim, Minwoo; Choi, Eun Ha; Kim, Yun-Ji

    2016-10-01

    In this study, we investigated the inactivation effects on murine norovirus (MNV-1) with/without purification in water using a submerged plasma reactor of arc discharge (underwater arc), which produced a shockwave, UV light, reactive oxygen species and reactive nitrogen species. Underwater arc treatments of 3 and 6 Hz at 12 kV resulted in 2.6- and 4.2-log reductions in the virus titer of non-purified MNV-1 after 1 min of treatment, respectively. The reduction of purified MNV-1 was higher than that of non-purified MNV-1 after underwater arc treatment for all applied conditions (12 or 15 kV and 3 or 6 Hz). One of the viral capsid proteins (VP1) was not detectable after underwater arc treatment, when its integrity was assessed by western blot analysis. Transmission electron microscopy analysis also revealed that MNV-1 particles were completely dissembled by the treatment. This study demonstrates that underwater arc treatment, which was capable of disintegrating the MNV-1 virion structure and the viral capsid protein, can be an effective disinfection process for the inactivation of water-borne noroviruses. PMID:27379726

  19. High-order harmonic generation in a capillary discharge

    DOEpatents

    Rocca, Jorge J.; Kapteyn, Henry C.; Mumane, Margaret M.; Gaudiosi, David; Grisham, Michael E.; Popmintchev, Tenio V.; Reagan, Brendan A.

    2010-06-01

    A pre-ionized medium created by a capillary discharge results in more efficient use of laser energy in high-order harmonic generation (HHG) from ions. It extends the cutoff photon energy, and reduces the distortion of the laser pulse as it propagates down the waveguide. The observed enhancements result from a combination of reduced ionization energy loss and reduced ionization-induced defocusing of the driving laser as well as waveguiding of the driving laser pulse. The discharge plasma also provides a means to spectrally tune the harmonics by tailoring the initial level of ionization of the medium.

  20. High voltage pulse ignition of mercury discharge hollow cathodes

    NASA Technical Reports Server (NTRS)

    Wintucky, E. G.

    1973-01-01

    A high voltage pulse generated by a capacitor discharge into a step-up transformer has been demonstrated capable of consistently igniting hollow cathode mercury discharges at propellant flows and heater power levels much below those required by conventional cathode starting. Results are presented for 3.2-mm diameter enclosed and open keeper cathodes. Starting characteristics are shown to depend on keeper voltage, mercury flow rate, heater power, keeper orifice size, emissive materials, and electrode to which the pulse is applied. This starting technique has been used to start a cathode over 10,000 times without any degradation of starting capability.

  1. High efficiency ionizer using a hollow cathode discharge plasma

    SciTech Connect

    Alessi, J.G.; Prelec, K.

    1984-01-01

    A proposal for an ionizer using a hollow cathode discharge plasma is described. Ionization is via the very high current density electron beam component in the plasma, as well as from charge exchange with plasma ions. Extraction of a He/sup +/ current corresponding to approximately 50% of the incoming atomic beam flux should be possible.

  2. Nonlinear behavior in high-intensity discharge lamps

    NASA Astrophysics Data System (ADS)

    Baumann, Bernd; Schwieger, Joerg; Wolff, Marcus; Manders, Freddy; Suijker, Jos

    2016-06-01

    The light flicker problem of high intensity discharge lamps is studied numerically and experimentally. It is shown that in some respects the systems behave very similar to the forced Duffing oscillator with a softening spring. In particular, the jump phenomenon and hysteresis are observed in the simulations and in the experiments.

  3. Process for increasing the water discharge of water delivering drilled wells, previously used for water delivery, and having decreased water discharge

    SciTech Connect

    Gomory, P.; Hegedus, J.; Kiss, F.; Simon, A.

    1985-09-17

    Process for increasing the water discharge of water delivering drilled wells, which can be characterized in that into the filter section of the well weak acids with a dissociation constant being less than K /SUB d/ =10/sup -3/ are introduced. After a dwelling period of longer duration, expediently 10 to 48 hours, as well as compressing, flushing is performed by means of a scavenging pump. Thereafter the solution of sodium bicarbonate and/or sodium hypochlorite is introduced into the filter section. After a longer dwelling period, expediently one to thirty-six hours, flushing is performed by means of the scavenging pump. As weak acids with a dissociation constant being less than K /SUB d/ =10/sup -3/ acetic acid, tartaric acid, citric acid, metaboric and/or tetraboric acid is used.

  4. Glow discharge deposition at high rates using disilane

    SciTech Connect

    Rajeswaran, G.; Corderman, R.R.; Kampas, F.J.; Vanier, P.E.

    1985-01-01

    The research program reported makes use of the fact that amorphous silicon films can be grown faster from disilane in a glow discharge than from the traditional silane. The goal is to find a method to grow films at a high rate and with sufficiently high quality to be used in an efficient solar cell. It must also be demonstrated that the appropriate device structure can be successfully fabricated under conditions which give high deposition rates. High quality intrinsic films have been deposited at 20 A/s. Efficiency of 5.6% on steel substrates and 5.3% on glass substrates were achieved using disilane i-layers deposited at 15 A/s in a basic structure, without wide-gap doped layers or light trapping. Wide gap p-layers were deposited using disilane. Results were compared with those obtained at Vactronic using high power discharges of silane-hydrogen mixtures. (LEW)

  5. Statistical prediction of seasonal discharge in the Naryn basin for water resources planning in Central Asia

    NASA Astrophysics Data System (ADS)

    Apel, Heiko; Gafurov, Abror; Gerlitz, Lars; Unger-Shayesteh, Katy; Vorogushyn, Sergiy; Merkushkin, Aleksandr; Merz, Bruno

    2016-04-01

    exceptionally high skill reaching explained variances of 86% in the cross validation using ModSnow processed snow cover data and CRU temperature and precipitation data, i.e. freely available data only. Using antecedent discharge information from the Uchterek station over the period January to April the skill can be improved even further. Also the addition of latest EGSIEM GRACE products can improve this skill to > 90% explained variance by replacing the CRU temperature data in the forecast model. From all variables the ModSnow processed MODIS snow cover data proved to be the most important predictor. However, although the prediction models proved to be robust in the cross validation, it has to be mentioned that the models are based on a limited time spanning the period 2000-2012 only. Nevertheless it is believed that the models are reliable, as this time period shows a high variability in seasonal water availability spanning from exceptionally dry to wet years. In summary, the developed forecast model may be a valuable complementary tool for the seasonal discharge prediction in Central Asia for water resources planning, that does not suffer from limited data access required for other forecast methods.

  6. Discharge and water quality of Horse Creek, southeastern Wyoming, May-November, 1985

    USGS Publications Warehouse

    Meyer, J.F.; Lenfest, L.W., Jr.

    1986-01-01

    This report presents stream-discharge and water-quality data collected at five sites in the lower Horse Creek drainage of southeastern Wyoming, May through November, 1985. Data include stream-discharge measurements; field measurements of specific conductance, pH, and water temperature; and computer changes in stream discharge. Measured discharge in Horse Creek ranged from 0.91 to 172 cu ft/sec. Values of pH averaged 8.4. Water temperature ranged from 0 to 27 C. The data are presented in graphs and tables. A map of the study reach shows the location of the data collection sites. (USGS)

  7. Constraints for Using Radon-in-Water Concentrations as an Indicator for Groundwater Discharge into Surface Water Bodies

    NASA Astrophysics Data System (ADS)

    Petermann, Eric; Schubert, Michael

    2015-04-01

    The radon (222-Rn) activity concentration of surface water is a favourable indicator for the detection of groundwater discharge into surface water bodies since radon is highly enriched in groundwater relative to surface waters. Hence, positive radon-in-water anomalies are interpreted as groundwater discharge locations. For this approach, usually, radon time-series are recorded along transects in near-surface waters. Time-series of radon-in-water concentration are commonly measured by permanent radon extraction from a water pump stream and continuous monitoring of the resulting radon-in-air concentration by means of a suitable radon detector. Radon-in-water concentrations are derived from the recorded radon-in-air signal by making allowances for water/air partitioning of radon. However, several constraints arise for this approach since undesirable factors are influencing the radon-in-water concentration. Consequently, corrections are required to remove the effect of these undesirable factors from the radon signal. First, an instrument inherent response delay between actual changes in the radon-in-water concentration and the related radon-in-air signal was observed during laboratory experiments. The response delay is due to (i) the water/air transfer kinetics of radon and (ii) the delayed decay equilibrium between radon and its progeny polonium (218-Po), which is actually being measured by most radon-in-air monitors. We developed a physical model, which considers all parameters that are responsible for the response delay. This model allows the reconstruction of radon-in-water time-series based on radon-in-air records. Second, on a time-scale of several hours the tidal stage is known as a major driver for groundwater discharge fluctuations due to varying hydraulic gradients between groundwater and surface water during a tidal cycle. Consequently, radon-in-water time-series that are detected on tidal coasts are not comparable among each other without normalization

  8. Probability-based classifications for spatially characterizing the water temperatures and discharge rates of hot springs in the Tatun Volcanic Region, Taiwan.

    PubMed

    Jang, Cheng-Shin

    2015-05-01

    Accurately classifying the spatial features of the water temperatures and discharge rates of hot springs is crucial for environmental resources use and management. This study spatially characterized classifications of the water temperatures and discharge rates of hot springs in the Tatun Volcanic Region of Northern Taiwan by using indicator kriging (IK). The water temperatures and discharge rates of the springs were first assigned to high, moderate, and low categories according to the two thresholds of the proposed spring classification criteria. IK was then used to model the occurrence probabilities of the water temperatures and discharge rates of the springs and probabilistically determine their categories. Finally, nine combinations were acquired from the probability-based classifications for the spatial features of the water temperatures and discharge rates of the springs. Moreover, various combinations of spring water features were examined according to seven subzones of spring use in the study region. The research results reveal that probability-based classifications using IK provide practicable insights related to propagating the uncertainty of classifications according to the spatial features of the water temperatures and discharge rates of the springs. The springs in the Beitou (BT), Xingyi Road (XYR), Zhongshanlou (ZSL), and Lengshuikeng (LSK) subzones are suitable for supplying tourism hotels with a sufficient quantity of spring water because they have high or moderate discharge rates. Furthermore, natural hot springs in riverbeds and valleys should be developed in the Dingbeitou (DBT), ZSL, Xiayoukeng (XYK), and Macao (MC) subzones because of low discharge rates and low or moderate water temperatures. PMID:25917185

  9. Specific Conductivity Synoptic Surveys to Map Groundwater-Surface Water Discharges in a Lowland River

    NASA Astrophysics Data System (ADS)

    Pai, H.; Villamizar, S. R.; Harmon, T. C.

    2014-12-01

    Quantifying distributed groundwater-surface water (GW-SW) discharges at the watershed scale is a challenging but important aspect of tracking nonpoint-source pollutants and their potential impacts on riverine water quality. This work analyzes high spatiotemporal longitudinal river sampling along a 38 km reach of the lower Merced River (LMR) in California's San Joaquin River (SJR) watershed and estimates GW-SW discharges using a simple discretized mixing model. The LMR flow is dam-controlled upstream and has several distributed surface discharges from SW diversions, SW canal inputs, and potential GW discharges influenced by the surrounding agricultural and municipal landscapes. We collected longitudinal datasets covering a wide range of flows (1.3 to 150 m3/s), sampling georeferenced water specific conductance (SC) at intervals of less than 1 minute. Whole-reach gradients of SW specific conductance (SC), representing GW-SW salinity loading (mS/cm/river km), decreased in proportion to the flow and stage, indicating either (1) a simple dilution effect or (2) reduced GW-SW discharges due to a reduced GW-SW hydraulic gradient at higher stages. With respect to distributed discharges, local gradients were significant (p < 0.05), with estimated local salinity loads varying from -0.4 to 8.9 mS/cm/river km for the LMR conditions. Using local groundwater salinity estimates, we inverted a discretized mixing model to estimate distributed groundwater fluxes. Summation of the fluxes agreed well with stream gage estimates. However, local flux estimates were nonuniform, with mid-reach values consistently increasing to a maximum value at intermediate stream flows, then decreasing for greater flows. Causes for this behavior remain uncertain but may be due to one or more of the following: (1) uncertainty in the groundwater salinity data, (2) salinity reduction in the hyporheic zone (e.g., denitrification), and (3) access to preferential GW-SW flowpaths at intermediate flows and stages

  10. Improvement of growth rate of plants by bubble discharge in water

    NASA Astrophysics Data System (ADS)

    Takahata, Junichiro; Takaki, Koichi; Satta, Naoya; Takahashi, Katsuyuki; Fujio, Takuya; Sasaki, Yuji

    2015-01-01

    The effect of bubble discharge in water on the growth rate of plants was investigated experimentally for application to plant cultivation systems. Spinach (Spinacia oleracea), radish (Raphanus sativus var. sativus), and strawberry (Fragaria × ananassa) were used as specimens to clarify the effect of the discharge treatment on edible parts of the plants. The specimens were cultivated in pots filled with artificial soil, which included chicken manure charcoal. Distilled water was sprayed on the artificial soil and drained through a hole in the pots to a water storage tank. The water was circulated from the water storage tank to the cultivation pots after 15 or 30 min discharge treatment on alternate days. A magnetic compression-type pulsed power generator was used to produce the bubble discharge with a repetition rate of 250 pps. The plant height in the growth phase and the dry weight of the harvested plants were improved markedly by the discharge treatment in water. The soil and plant analyzer development (SPAD) value of the plants also improved in the growth phase of the plants. The concentration of nitrate nitrogen, which mainly contributed to the improvement of the growth rate, in the water increased with the discharge treatment. The Brix value of edible parts of Fragaria × ananassa increased with the discharge treatment. The inactivation of bacteria in the water was also confirmed with the discharge treatment.

  11. Surface water quality management using an integrated discharge permit and the reclaimed water market.

    PubMed

    Jamshidi, Shervin; Niksokhan, Mohammad Hossein; Ardestani, Mojtaba

    2014-01-01

    Water quality trading is a sustainable framework for surface water quality management. It uses discharge permits to reduce the total treatment costs. For example, the case of Gharesoo River in Iran shows that the nitrogen permit market between point and non-point sources is 37% more economical than the command and control framework. Nevertheless, the cost saving may be reduced to 6% by the end of the study period (2050). This depression may be due to the limited technical support for wastewater treatment plants. Therefore, an integrated market is recommended in which the discharge permits and the reclaimed water are traded simultaneously. In this framework, the allocation of secondary treated domestic wastewater for irrigation can provide capacity for other pollutants to discharge into the surface water. This innovative approach may decrease the total treatment costs by 63% at present, while 65%, may be achieved by the end of the study period. Furthermore, this market is able to determine the environmental penalty, trading permits, and reuse prices. For example, the maximum ratio of the average reuse price to the penalty cost is determined as 1 to 10. It is introduced as an incentive indicator for stakeholders to consider the integrated market. Consequently, the applicability and the efficiency of using this approach are verified long term. PMID:25225941

  12. Relatively high plasma density in low pressure inductive discharges

    SciTech Connect

    Kang, Hyun-Ju; Kim, Yu-Sin; Chung, Chin-Wook

    2015-09-15

    Electron energy probability functions (EEPFs) were measured in a low pressure argon inductive discharge. As radio frequency (RF) power increases, discharge mode is changed from E-mode (capacitively coupled) to H-mode (inductively coupled) and the EEPFs evolve from a bi-Maxwellian distribution to a Maxwellian distribution. It is found that the plasma densities at low RF powers (<30 W) are much higher than the density predicted from the slope of the densities at high powers. Because high portion of high energy electrons of the bi-Maxwellian distribution lowers the collisional energy loss and low electron temperature of low energy electrons reduces particle loss rate at low powers. Therefore, the energy loss of plasma decreases and electron densities become higher at low powers.

  13. Reconnaissance investigations of the discharge and water quality of the Amazon River

    USGS Publications Warehouse

    Oltman, Roy Edwin

    1968-01-01

    Selected published estimates of the discharge of Amazon River in the vicinity of Obidos and the mouth are presented to show the great variance of available information. The most reasonable estimates prepared by those who measured some parameters of the flow were studied by Maurice Parde, who concluded that the mean annual discharge is 90,000 to 100,000 cms (cubic meters per second) or 3,200,000 to 3,500,000 cfs (cubic feet per second). A few published estimates of discharge at mouth of 110,000 cms (3,900,000 cfs) based on rainfall-runoff relationships developed for other humid regions of the world are available. Three measurements of discharge made at the Obidos narrows in 1963-64 by a joint Brazil-United States expedition at high, low, and medium river stage are referred to the datum used at the Obidos gage during the period of operation, 1928-46, and a relationship between stage and discharge prepared on the basis of the measurements and supplementary data and computations. Recovery of the original Obidos gage datum is verified by referring the 1963-64 concurrent river stages at Manaus, Obidos, and Taperinha to gage relation curves developed for Manaus-Obidos and Obidos-Taperinha for periods of concurrent operation, 1928-46 and 1931-46, respectively. The average discharge, based on the stage-discharge relation and record of river stage for the period 1928-46, is computed to be 5,500,000 cfs (157,000 cms) for the Obidos site. The greatest known flood at Obidos, that of June 1953, is computed to have been a flow of 12,500,000 cfs (350,000 cms) at stage of 7.6 meters (24.9 feet) in the main channel and an indeterminate amount of overflow which, under the best assumed overflow conditions, may have amounted to about 10 percent of the main channel flow. Overflow discharge at stage equivalent to mean annual discharge is judged to be an insignificant percentage of flow down the main channel. Miscellaneous data collected during the flow measurements show that the tidal

  14. Characterization of high power impulse magnetron sputtering discharges

    NASA Astrophysics Data System (ADS)

    Hala, Matej

    Paper I: In the first paper, we present a new approach in the characterization of the high power pulsed magnetron sputtering (HiPIMS) discharge evolution—time- and species-resolved plasma imaging—employing a set of band-pass optical interference filters suitable for the isolation of the emission originating from different species populating the plasma. We demonstrate that the introduction of such filters can be used to distinguish different phases of the discharge, and to visualize numerous plasma effects including background gas excitations during the discharge ignition, gas shock waves, and expansion of metal-rich plasmas. In particular, the application of this technique is shown on the diagnostics of the 200 µs long non-reactive HiPIMS discharges using a Cr target. Paper II: In order to gain further information about the dynamics of reactive HiPIMS discharges, both fast plasma imaging and time- and space-resolved optical emission spectroscopy (OES) are used for a systematic investigation of the 200 µs long HiPIMS pulses operated in Ar, N2 and N 2/Ar mixtures and at various pressures. It is observed that the dense metal plasma created next to the target propagates in the reactor at a speed ranging from 0.7 to 3.5 km s-1, depending on the working gas composition and the pressure. In fact, it increases with higher N 2 concentration and with lower pressure. The visible form of the propagating plasma wave changes from a hemispherical shape in Ar to a drop-like shape extending far from the target with increasing N2 concentration, owing to the significant emission from molecular N2. Interestingly, the evidence of the target self-sputtering is found for all investigated conditions, including pure N2 atmosphere. Paper III: Here, we report on the time- and species-resolved plasma imaging analysis of the dynamics of the 200 µs long HiPIMS discharges above a Cr target ignited in pure O2. It is shown that the discharge emission is dominated solely by neutral and

  15. Experimental characterization of plasma formation and shockwave propagation induced by high power pulsed underwater electrical discharge.

    PubMed

    Claverie, A; Deroy, J; Boustie, M; Avrillaud, G; Chuvatin, A; Mazanchenko, E; Demol, G; Dramane, B

    2014-06-01

    High power pulsed electrical discharges into liquids are investigated for new industrial applications based on the efficiency of controlled shock waves. We present here new experimental data obtained by combination of detailed high speed imaging equipments. It allows the visualization of the very first instants of plasma discharge formation, and then the pulsations of the gaseous bubble with an accurate timing of events. The time history of the expansion/compression of this bubble leads to an estimation of the energy effectively transferred to water during the discharge. Finally, the consecutive shock generation driven by this pulsating bubble is optically monitored by shadowgraphs and schlieren setup. These data provide essential information about the geometrical pattern and chronometry associated with the shock wave generation and propagation. PMID:24985821

  16. Experimental study of the water jet induced by underwater electrical discharge in a narrow rectangular tube

    NASA Astrophysics Data System (ADS)

    Koita, T.; Zhu, Y.; Sun, M.

    2016-05-01

    This paper reports an experimental investigation on the effects of explosion depth and tube width on the water jet induced by an underwater electrical discharge in a narrow rectangular tube. The water jet formation and bubble structure were evaluated from the images recorded by a high-speed video camera. Two typical patterns of jet formation and four general patterns of bubble implosion were observed, depending on the explosion depth and tube width. The velocity of the water jet was calculated from the recorded images. The jet velocity was observed to depend on not only the explosion depth and energy, but also on the tube width. We proposed an empirical formula defining the water jet velocity in the tube as a function of the tube width and explosion depth and energy.

  17. Plasma Discharges in Gas Bubbles in Liquid Water: Breakdown Mechanisms and Resultant Chemistry

    NASA Astrophysics Data System (ADS)

    Gucker, Sarah M. N.

    The use of atmospheric pressure plasmas in gases and liquids for purification of liquids has been investigated by numerous researchers, and is highly attractive due to their strong potential as a disinfectant and sterilizer. However, the fundamental understanding of plasma production in liquid water is still limited. Despite the decades of study dedicated to electrical discharges in liquids, many physical aspects of liquids, such as the high inhomogeneity of liquids, complicate analyses. For example, the complex nonlinearities of the fluid have intricate effects on the electric field of the propagating streamer. Additionally, the liquid material itself can vaporize, leading to discontinuous liquid-vapor boundaries. Both can and do often lead to notable hydrodynamic effects. The chemistry of these high voltage discharges on liquid media can have circular effects, with the produced species having influence on future discharges. Two notable examples include an increase in liquid conductivity via charged species production, which affects the discharge. A second, more complicated scenario seen in some liquids (such as water) is the doubling or tripling of molecular density for a few molecule layers around a high voltage electrode. These complexities require technological advancements in optical diagnostics that have only recently come into being. This dissertation investigates several aspects of electrical discharges in gas bubbles in liquids. Two primary experimental configurations are investigated: the first allows for single bubble analysis through the use of an acoustic trap. Electrodes may be brought in around the bubble to allow for plasma formation without physically touching the bubble. The second experiment investigates the resulting liquid phase chemistry that is driven by the discharge. This is done through a dielectric barrier discharge with a central high voltage surrounded by a quartz discharge tube with a coil ground electrode on the outside. The plasma

  18. Influence of water conductivity on particular electrospray modes with dc corona discharge — optical visualization approach

    NASA Astrophysics Data System (ADS)

    Pongrác, Branislav; Kim, Hyun-Ha; Negishi, Nobuaki; Machala, Zdenko

    2014-08-01

    The effect of water conductivity on electrospraying of water was studied in combination with positive DC corona discharge generated in air. We used a point-to-plane geometry of electrodes with a hollow syringe needle anode opposite to the metal mesh cathode. We employed total average current measurements and high-speed camera fast time-resolved imaging. We visualized the formation of a water jet (filament) and investigated corona discharge behavior for various water conductivities. Depending on the conductivity, various jet properties were observed: pointy, prolonged, and fast spreading water filaments for lower conductivity; in contrast to rounder, broader, and shorter quickly disintegrating filaments for higher conductivity. The large acceleration values (4060 m/s2 and 520 m/s2 for 2 μS/cm and 400 μS/cm, respectively) indicate that the process is mainly governed by the electrostatic force. In addition, with increasing conductivity, the breakdown voltage for corona-to-spark transition was decreasing.

  19. Investigation of free discharge through the hydro units of high head Francis turbine

    NASA Astrophysics Data System (ADS)

    Kuznetsov, I.; Zakharov, A.; Orekhov, G.; Minakov, A.; Dekterev, A.; Platonov, D.

    2012-11-01

    Free discharge through the units is applied in the course of construction of hydro power plant or in case of excessive water inflow during floods or emergency situation. Free discharges throw the hydro units at 80 m head and more are unknown. Possibility of high velocity swirling flow discharged through the whole hydro unit consisting of penstock, turbine (with Francis runner and distributor or without them) and draft tube is being analyzed in the present paper. Investigation method is based on mathematical simulation of unsteady flow through the hydro unit under the following conditions: with the free running or locked runner and with removed runner. Physical researches of the swirling flow behavior in the model bent penstocks and model turbine water passages have been performed. Based on the results of calculations and model tests the following extensive data have been obtained: pressure fluctuation in the whole hydro unit, fluctuation of hydrodynamic forces acting on guide vanes, torque fluctuation on the runner and discharge fluctuation. Thus, based on this data preferable designs of free discharge are proposed.

  20. Zero Discharge Water Management for Horizontal Shale Gas Well Development

    SciTech Connect

    Paul Ziemkiewicz; Jennifer Hause; Raymond Lovett; David Locke Harry Johnson; Doug Patchen

    2012-03-31

    Hydraulic fracturing technology (fracking), coupled with horizontal drilling, has facilitated exploitation of huge natural gas (gas) reserves in the Devonian-age Marcellus Shale Formation (Marcellus) of the Appalachian Basin. The most-efficient technique for stimulating Marcellus gas production involves hydraulic fracturing (injection of a water-based fluid and sand mixture) along a horizontal well bore to create a series of hydraulic fractures in the Marcellus. The hydraulic fractures free the shale-trapped gas, allowing it to flow to the well bore where it is conveyed to pipelines for transport and distribution. The hydraulic fracturing process has two significant effects on the local environment. First, water withdrawals from local sources compete with the water requirements of ecosystems, domestic and recreational users, and/or agricultural and industrial uses. Second, when the injection phase is over, 10 to 30% of the injected water returns to the surface. This water consists of flowback, which occurs between the completion of fracturing and gas production, and produced water, which occurs during gas production. Collectively referred to as returned frac water (RFW), it is highly saline with varying amounts of organic contamination. It can be disposed of, either by injection into an approved underground injection well, or treated to remove contaminants so that the water meets the requirements of either surface release or recycle use. Depending on the characteristics of the RFW and the availability of satisfactory disposal alternatives, disposal can impose serious costs to the operator. In any case, large quantities of water must be transported to and from well locations, contributing to wear and tear on local roadways that were not designed to handle the heavy loads and increased traffic. The search for a way to mitigate the situation and improve the overall efficiency of shale gas production suggested a treatment method that would allow RFW to be used as make

  1. High energy XeBr electric discharge laser

    DOEpatents

    Sze, Robert C.; Scott, Peter B.

    1981-01-01

    A high energy XeBr laser for producing coherent radiation at 282 nm. The XeBr laser utilizes an electric discharge as the excitation source to minimize formation of molecular ions thereby minimizing absorption of laser radiation by the active medium. Additionally, HBr is used as the halogen donor which undergoes harpooning reactions with Xe.sub.M * to form XeBr*.

  2. Properties of UN Sintered by High Voltage Electric Discharge Consolidation

    NASA Astrophysics Data System (ADS)

    Yurlova, M.; Tarasov, B.; Shornikov, D.; Grigoryev, E.; Olevsky, E.

    In the present work, the opportunity of the consolidation of uranium nitride tablets by high voltage electric discharge consolidation (HVEDC) is considered. It is shown that the consolidation by HVEDC allows the prevention of the expansion of uranium nitride powders and renders pellets with relative density of up to 97%. The thermal stability of the obtained samples has been investigated. The analysis of the microstructure of the processed samples indicates the retention of the initial powder structure

  3. High energy XeBr electric discharge laser

    DOEpatents

    Sze, R.C.; Scott, P.B.

    A high energy XeBr laser for producing coherent radiation at 282 nm is disclosed. The XeBr laser utilizes an electric discharge as the excitation source to minimize formation of molecular ions thereby minimizing absorption of laser radiation by the active medium. Additionally, HBr, is used as the halogen donor which undergoes harpooning reactions with Xe/sub M/ to form XeBr.

  4. High energy KrCl electric discharge laser

    DOEpatents

    Sze, R.C.; Scott, P.B.

    A high energy KrCl laser is presented for producing coherent radiation at 222 nm. Output energies on the order of 100 mJ per pulse are produced utilizing a discharge excitation source to minimize formation of molecular ions, thereby minimizing absorption of laser radiation by the active medium. Additionally, HCl is used as a halogen donor which undergoes a harpooning reaction with metastable Kr/sub M/ to form KrCl.

  5. High energy KrCl electric discharge laser

    DOEpatents

    Sze, Robert C.; Scott, Peter B.

    1981-01-01

    A high energy KrCl laser for producing coherent radiation at 222 nm. Output energies on the order of 100 mJ per pulse are produced utilizing a discharge excitation source to minimize formation of molecular ions, thereby minimizing absorption of laser radiation by the active medium. Additionally, HCl is used as a halogen donor which undergoes a harpooning reaction with metastable Kr.sub.M * to form KrCl.

  6. Electric discharges produced by clouds of charged water droplets in the presence of moving conducting object

    NASA Astrophysics Data System (ADS)

    Kostinskiy, Alexander Y.; Syssoev, Vladimir S.; Mareev, Eugene A.; Rakov, Vladimir A.; Andreev, Mikhail G.; Bogatov, Nikolai A.; Makal'sky, Leonid M.; Sukharevsky, Dmitry I.; Aleshchenko, Alexander S.; Kuznetsov, Vladimir E.; Shatalina, Maria V.

    2015-12-01

    The possibility of initiation of electric discharges by a crossbow bolt (projectile) moving in the electric field of a cloud of negatively charged water droplets has been demonstrated for the first time. Over one hundred of discharges have been produced. For each event, a high-speed video camera recorded the images of upward positive leaders developing from both the nearby grounded sphere and the projectile, followed by the return-stroke-like process. Corresponding currents were measured and integrated photos of the events were obtained. The results can help to improve our understanding of lightning initiation by airborne vehicles and by a vertical conductor rapidly extended below the thundercloud in order to trigger lightning with the rocket-and-wire technique.

  7. Analyzing Conductivity Profiles in Stream Waters Influenced by Mine Water Discharges

    NASA Astrophysics Data System (ADS)

    Räsänen, Teemu; Hämäläinen, Emmy; Hämäläinen, Matias; Turunen, Kaisa; Pajula, Pasi; Backnäs, Soile

    2015-04-01

    Conductivity is useful as a general measure of stream water quality. Each stream inclines to have a quite constant range of conductivity that can be used as a baseline for comparing and detecting influence of contaminant sources. Conductivity in natural streams and rivers is affected primarily by the geology of the watershed. Thus discharges from ditches and streams affect not only the flow rate in the river but also the water quality and conductivity. In natural stream waters, the depth and the shape of the river channel change constantly, which changes also the water flow. Thus, an accurate measuring of conductivity or other water quality indicators is difficult. Reliable measurements are needed in order to have holistic view about amount of contaminants, sources of discharges and seasonal variation in mixing and dilution processes controlling the conductivity changes in river system. We tested the utility of CastAway-CTD measuring device (SonTek Inc) to indicate the influence of mine waters as well as mixing and dilution occurring in the recipient river affected by treated dewatering and process effluent water discharges from a Finnish gold mine. The CastAway-CTD measuring device is a small, rugged and designed for profiling of depths of up to 100m. Device measures temperature, salinity, conductivity and sound of speed using 5 Hz response time. It has also built-in GPS which produces location information. CTD casts are normally used to produce vertical conductivity profile for rather deep waters like seas or lakes. We did seasonal multiple Castaway-CTD measurements during 2013 and 2014 and produced scaled vertical and horizontal profiles of conductivity and water temperature at the river. CastAway-CTD measurement pinpoints how possible contaminants behave and locate in stream waters. The conductivity profiles measured by CastAway-CTD device show the variation in maximum conductivity values vertically in measuring locations and horizontally in measured cross

  8. Volume Diffuse Dielectric Barrier Discharge Plasma Produced by Nanosecond High Voltage Pulse in Airflow

    NASA Astrophysics Data System (ADS)

    Qi, Haicheng; Gao, Wei; Fan, Zhihui; Liu, Yidi; Ren, Chunsheng

    2016-05-01

    Volume diffuse dielectric barrier discharge (DBD) plasma is produced in subsonic airflow by nanosecond high-voltage pulse power supply with a plate-to-plate discharge cell at 6 mm air gap length. The discharge images, optical emission spectra (OES), the applied voltage and current waveforms of the discharge at the changed airflow rates are obtained. When airflow rate is increased, the transition of the discharge mode and the variations of discharge intensity, breakdown characteristics and the temperature of the discharge plasma are investigated. The results show that the discharge becomes more diffuse, discharge intensity is decreased accompanied by the increased breakdown voltage and time lag, and the temperature of the discharge plasma reduces when airflow of small velocity is introduced into the discharge gap. These phenomena are because that the airflow changes the spatial distribution of the heat and the space charge in the discharge gap. supported by National Natural Science Foundation of China (No. 51437002)

  9. [Removal of SO2 from flue gas by water vapor DC corona discharge].

    PubMed

    Sun, Ming; Wu, Yan

    2006-07-01

    The influence of several factors on removal rate of SO2 from flue gas in unsaturated water vapor DC corona discharge was researched. Furthermore, the experiments of the removal rate of SO2 in pulsed discharge increased by water vapor DC corona discharge plasma were conducted. The experiment system is supplied with multi-nozzle-plate electrodes and the flow of simulated flue gas is under 70 m3/h. The results show that removal rate of SO2 can be improved by increasing the concentration of water vapor, intensity of electric field or decreasing flow of simulated flue gas. In unsaturated water vapor DC corona discharge, removal rate of SO2 can be improved by 10%, when NH3 is added as NH3 and SO2 is in a mole ratio of two to one, it can reach 60%. The removal rate of SO2 can be increased by 5% in pulsed corona discharge and reach above 90%. PMID:16881295

  10. The electro-acoustic transition process of pulsed corona discharge in conductive water

    NASA Astrophysics Data System (ADS)

    Huang, Yifan; Yan, Hui; Wang, Bingzhe; Zhang, Xuming; Liu, Zhen; Yan, Keping

    2014-06-01

    A pulsed corona discharge in conductive water is studied theoretically and experimentally via pre-discharge analysis, thermodynamic and dynamic processes of a plasma-containing bubble, an acoustic signature and energy partitioning. The total particle density and electron density inside the bubble, internal temperature and pressure, bubble radius and bubble wall Mach number are simulated by solving a set of equations including the ideal gas equation, Rayleigh equation and energy balance equation. The bubble radius is also measured by a high-speed charge-coupled device camera on a homemade experimental device. The acoustic waveforms and their power spectral density are calculated indirectly. By using several diagnostic tools, the electrical parameters of the load, light emission from the plasma and acoustic waveforms are recorded simultaneously. Simulation and experimental results of the bubble radius and acoustic signature agree reasonably well over the range of energy inputs from 5 to 30 J per pulse. Different kinds of terminations or intermediates of the energy transition process are analysed through simulation and experimental data. The electro-acoustic efficiency varies from 0.8% to 1.9%, while most of the discharge energy is consumed by circuit loss, Joule heating and thermal radiation, or is transformed into kinetic energy in the water.

  11. Multi-Model Assessment of Global Hydropower and Cooling Water Discharge Potential Under Climate Change

    NASA Technical Reports Server (NTRS)

    van Vliet, M. T. H.; van Beek, L. P. H.; Eisener, S.; Wada, Y.; Bierkens, M. F. P.

    2016-01-01

    Worldwide, 98% of total electricity is currently produced by thermoelectric power and hydropower. Climate change is expected to directly impact electricity supply, in terms of both water availability for hydropower generation and cooling water usage for thermoelectric power. Improved understanding of how climate change may impact the availability and temperature of water resources is therefore of major importance. Here we use a multi-model ensemble to show the potential impacts of climate change on global hydropower and cooling water discharge potential. For the first time, combined projections of streamflow and water temperature were produced with three global hydrological models (GHMs) to account for uncertainties in the structure and parametrization of these GHMs in both water availability and water temperature. The GHMs were forced with bias-corrected output of five general circulation models (GCMs) for both the lowest and highest representative concentration pathways (RCP2.6 and RCP8.5). The ensemble projections of streamflow and water temperature were then used to quantify impacts on gross hydropower potential and cooling water discharge capacity of rivers worldwide. We show that global gross hydropower potential is expected to increase between +2.4% (GCM-GHM ensemble mean for RCP 2.6) and +6.3% (RCP 8.5) for the 2080s compared to 1971-2000. The strongest increases in hydropower potential are expected for Central Africa, India, central Asia and the northern high-latitudes, with 18-33% of the world population living in these areas by the 2080s. Global mean cooling water discharge capacity is projected to decrease by 4.5-15% (2080s). The largest reductions are found for the United States, Europe, eastern Asia, and southern parts of South America, Africa and Australia, where strong water temperature increases are projected combined with reductions in mean annual streamflow. These regions are expected to affect 11-14% (for RCP2.6 and the shared socioeconomic

  12. Computer programs for describing the recession of ground-water discharge and for estimating mean ground-water recharge and discharge from streamflow records-update

    USGS Publications Warehouse

    Rutledge, A.T.

    1998-01-01

    The computer programs included in this report can be used to develop a mathematical expression for recession of ground-water discharge and estimate mean ground-water recharge and discharge. The programs are intended for analysis of the daily streamflow record of a basin where one can reasonably assume that all, or nearly all, ground water discharges to the stream except for that which is lost to riparian evapotranspiration, and where regulation and diversion of flow can be considered to be negligible. The program RECESS determines the master reces-sion curve of streamflow recession during times when all flow can be considered to be ground-water discharge and when the profile of the ground-water-head distribution is nearly stable. The method uses a repetitive interactive procedure for selecting several periods of continuous recession, and it allows for nonlinearity in the relation between time and the logarithm of flow. The program RORA uses the recession-curve displacement method to estimate the recharge for each peak in the streamflow record. The method is based on the change in the total potential ground-water discharge that is caused by an event. Program RORA is applied to a long period of record to obtain an estimate of the mean rate of ground-water recharge. The program PART uses streamflow partitioning to estimate a daily record of base flow under the streamflow record. The method designates base flow to be equal to streamflow on days that fit a requirement of antecedent recession, linearly interpolates base flow for other days, and is applied to a long period of record to obtain an estimate of the mean rate of ground-water discharge. The results of programs RORA and PART correlate well with each other and compare reasonably with results of the corresponding manual method.

  13. A comparative summary on streamers of positive corona discharges in water and atmospheric pressure gases

    NASA Astrophysics Data System (ADS)

    Tachibana, Kunihide; Motomura, Hideki

    2015-07-01

    From an intention of summarizing present understandings of positive corona discharges in water and atmospheric pressure gases, we tried to observe streamers in those media by reproducing and complementing previously reported results under a common experimental setup. We used a point-to-plane electrode configuration with different combinations of electrode gap (7 and 19 mm length) and pulsed power sources (0.25 and 2.5 ɛs duration). The general features of streamers were similar and the streamer-to-spark transition was also observed in both the media. However, in the details large differences were observed due to inherent nature of the media. The measured propagation speed of streamers in water of 0.035 × 106 ms-1 was much smaller than the speed in gases (air, N2 and Ar) from 0.4 to 1.1 × 106 ms-1 depending on species. In He the discharge looked glow-like and no streamer was observed. The other characteristics of streamers in gases, such as inception voltage, number of branches and thickness did also depend on the species. The thickness and the length of streamers in water were smaller than those in gases. From the volumetric expansion of a streamer in water after the discharge, the molecular density within the streamer medium was estimated to be rarefied from the density of water by about an order of magnitude in the active discharge phase. We derived also the electron density from the analysis of Stark broadened spectral lines of H and O atoms on the order of 1025 m-3 at the earlier time of the streamer propagation. The analyzed background blackbody radiation, rotational temperature of OH band emission and population density of Cu atomic lines yielded a consistent temperature of the streamer medium between 7000 and 10 000 K. Using the present data with a combination of the analysis of static electric field and previously reported results, we discuss the reason for the relatively low streamer inception voltage in water as compared to the large difference in the

  14. Water-Quality Assessment of Southern Florida - Wastewater Discharges and Runoff

    USGS Publications Warehouse

    Marella, Richard L.

    1998-01-01

    Nearly 800 million gallons per day of treated wastewater was discharged in the Southern Florida National Water-Quality Assessment (NAWQA) study unit in 1990, most to the Atlantic Ocean (44 percent) and to deep, saline aquifers (25 percent). About 9 percent was discharged to fresh surface waters and about 22 percent to shallow ground water, of which septic tanks accounted for 9 percent. Runoff from agricultural and urban lands, though not directly measured, is a large source of wastewater in southern Florida.

  15. Ground-water discharge determined from estimates of evapotranspiration, Death Valley regional flow system, Nevada and California

    USGS Publications Warehouse

    Laczniak, Randell J.; Smith, J. LaRue; Elliott, Peggy E.; DeMeo, Guy A.; Chatigny, Melissa A.; Roemer, Gaius J.

    2001-01-01

    The Death Valley regional flow system (DVRFS) is one of the larger ground-water flow systems in the southwestern United States and includes much of southern Nevada and the Death Valley region of eastern California. Centrally located within the ground-water flow system is the Nevada Test Site (NTS). The NTS, a large tract covering about 1,375 square miles, historically has been used for testing nuclear devices and currently is being studied as a potential repository for the long-term storage of high-level nuclear waste generated in the United States. The U.S. Department of Energy, as mandated by Federal and State regulators, is evaluating the risk associated with contaminants that have been or may be introduced into the subsurface as a consequence of any past or future activities at the NTS. Because subsurface contaminants can be transported away from the NTS by ground water, components of the ground-water budget are of great interest. One such component is regional ground-water discharge. Most of the ground water leaving the DVRFS is limited to local areas where geologic and hydrologic conditions force ground water upward toward the surface to discharge at springs and seeps. Available estimates of ground-water discharge are based primarily on early work done as part of regional reconnaissance studies. These early efforts covered large, geologically complex areas and often applied substantially different techniques to estimate ground-water discharge. This report describes the results of a study that provides more consistent, accurate, and scientifically defensible measures of regional ground-water losses from each of the major discharge areas of the DVRFS. Estimates of ground-water discharge presented in this report are based on a rigorous quantification of local evapotranspiration (ET). The study identifies areas of ongoing ground-water ET, delineates different ET areas based on similarities in vegetation and soil-moisture conditions, and determines an ET rate for

  16. Yield of Ozone, Nitrite Nitrogen and Hydrogen Peroxide Versus Discharge Parameter Using APPJ Under Water

    NASA Astrophysics Data System (ADS)

    Chen, Bingyan; Zhu, Changping; Fei, Juntao; He, Xiang; Yin, Cheng; Wang, Yuan; Gao, Ying; Jiang, Yongfeng; Wen, Wen; Chen, Longwei

    2016-03-01

    Discharge plasma in and in contact with water can be accompanied with ultraviolet radiation and electron impact, thus can generate hydroxyl radicals, ozone, nitrite nitrogen and hydrogen peroxide. In this paper, a non-equilibrium plasma processing system was established by means of an atmospheric pressure plasma jet immersed in water. The hydroxyl intensities and discharge energy waveforms were tested. The results show that the positive and negative discharge energy peaks were asymmetric, where the positive discharge energy peak was greater than the negative one. Meanwhile, the yield of ozone and nitrite nitrogen was enhanced with the increase of both the treatment time and the discharge energy. Moreover, the pH value of treated water was reduced rapidly and maintained at a lower level. The residual concentration of hydrogen peroxide in APPJ treated water was kept at a low level. Additionally, both the efficiency energy ratio of the yield of ozone and nitrite nitrogen and that of the removal of p-nitrophenol increased as a function of discharge energy and discharge voltage. The experimental results were fully analyzed and the chemical reaction equations and the physical processes of discharges in water were given. supported by National Natural Science Foundation of China (Nos. 11274092, 11404092, 61401146), the Nantong Science and Technology Project, Nantong, China (No. BK2014024), the Open Project of Jiangsu Province Key Laboratory of Environmental Engineering, Nanjing, China (No. KF2014001), and the Fundamental Research Funds for the Central Universities of China (No. 2014B11414)

  17. Pulsed Discharge Plasma over a Water Surface Induces Decoloration of Dyes

    NASA Astrophysics Data System (ADS)

    Wahyudiono; Machmudah, Siti; Goto, Motonobu

    2013-06-01

    It was well known that plasma can be defined as a partially ionized gas composed of ions, electrons and neutral species. Recently, plasma-water interaction has attracted growing interest as it may provide experimental chemists with a quite unique reaction medium. In this work, decoloration of dyes in water as a reaction media and the effects of various parameters with pulsed high-voltage discharge plasma are studied. Such as plasma applied under hydrothermal conditions generates high-energy electrons, ions, and radicals, which in turn may generate new reaction fields, leading to effective organic compounds oxidation for both homogeneous and heterogeneous reactions. Here, we utilize pulse discharge plasma over water surface to study the decoloration of Orange G, Orange II, Congo Red, and Naphthol Blue Black. They were directly fed as starting materials without additives. The experiments were conducted under argon atmospheric at 313 K using a batch type reactor. The products were directly analyzed by UV-Vis (ultra violet-visible) spectrophotometer V-550. The decoloration rate increased with increasing peak pulse voltage and pulse numbers, presumably due to the increased electric field energy. Based on these results, the present system may be promising.

  18. Global land-ocean linkage: direct inputs of nitrogen to coastal waters via submarine groundwater discharge

    NASA Astrophysics Data System (ADS)

    Beusen, A. H. W.; Slomp, C. P.; Bouwman, A. F.

    2013-09-01

    The role of submarine groundwater discharge (SGD), the leakage of groundwater from aquifers into coastal waters, in coastal eutrophication has been demonstrated mostly for the North American and European coastlines, but poorly quantified in other regions. Here, we present the first spatially explicit global estimates of N inputs via SGD to coastal waters and show that it has increased from about 1.0 to 1.4 Tg of nitrate (NO3-N) per year over the second half of the 20th century. Since this increase is not accompanied by an equivalent increase of groundwater phosphorus (P) and silicon (Si), SGD transport of nitrate is an important factor for the development of harmful algal blooms in coastal waters. Groundwater fluxes of N are linked to areas with high runoff and intensive anthropogenic activity on land, with Southeast Asia, parts of North and Central America, and Europe being hot spots.

  19. HIGH PERFORMANCE STATIONARY DISCHARGES IN THE DIII-D TOKAMAK

    SciTech Connect

    45th ANNUAL MEETING OF DIVISION OF PLASMA PHYSICS, ALBUQUERQUE, NEW MEXICO, OCTOBER 27-31,2003 AND TO BE PUBLISHED IN PHYS. PLASMAS.

    2003-10-01

    Recent experiments in the DIII-D tokamak [J.L. Luxon, Nucl. Fusion 42,614 (2002)] have demonstrated high {beta} with good confinement quality under stationary conditions. Two classes of stationary discharges are observed--low q{sub 95} discharges with sawteeth and higher q{sub 95} without sawteeth. The discharges are deemed stationary when the plasma conditions are maintained for times greater than the current profile relaxation time. In both cases the normalized fusion performance ({beta}{sub N}H{sub 89P}/q{sub 95}{sup 2}) reaches or exceeds the value of this parameter projected for Q{sub fus} = 10 in the International Thermonuclear Experimental Reactor (ITER) design [R. Aymar, et al., Plasma Phys. Control. Fusion 44, 519 (2002)]. The presence of sawteeth reduces the maximum achievable normalized {beta}, while confinement quality (confinement time relative to scalings) is largely independent of q{sub 95}. Even with the reduced {beta} limit, the normalized fusion performance maximizes at the lowest q{sub 95}. Projections to burning plasma conditions are discussed, including the methodology of the projection and the key physics issues which still require investigation.

  20. CASE STUDY OF A MARINE DISCHARGE: COMPARISON OF EFFLUENT AND RECEIVING WATER TOXICITY

    EPA Science Inventory

    An on-site investigation was conducted in northeast Florida to evaluate the toxicity of a pulp and paper mill discharge and to determine whether there was any receiving water toxicity associated with that discharge. The species tested included the macroalga Champia parvula, the m...

  1. Anthropogenic effects on global riverine sediment and water discharge - a spatially explicit analysis

    NASA Astrophysics Data System (ADS)

    Cohen, S.; Kettner, A. J.; Syvitski, J. P.

    2013-12-01

    Changes in global riverine water discharge and suspended sediment flux over a 50-year period, 1960-2010 are studied, applying a new version of the WBMsed (WBMsed v.2.0) global hydrological water balance model. A new floodplain component is introduced to better represent water and sediment dynamics during periods of overbank discharge. Validated against data from 16 globally distributed stations, WBMsed v.2.0 simulation results show considerable improvement over the original model. Anthropogenic impact on sediment and water discharge is evaluated by comparing global scale simulations with and without human drivers and parameters (agricultural land use, water intake form aquifers and rivers, sediment trapping in reservoirs, and human-induced soil erosion). The results show that, on average, global riverine sediment flux is reduced by approximately 25% by anthropogenic activities (almost exclusively due to trapping in reservoirs) while water discharge is reduced by about 2%. These results correspond to previous analysis by other research groups. Substantial global and intra-basin variability is observed (see Figure 1) for the first time. In some regions an opposite anthropogenic effect on sediment and water discharge was predicted (e.g. west Mississippi Basin, Rio Grande River, Indian subcontinent). We discuss the western part of the Mississippi Basin as an example of this intriguing anthropogenic impact. Figure 1. Percent change between disturbed and pristine simulations (with and without human footprint respectively) for sediment flux (top) and water discharge (bottom).

  2. Influence of Sodium Carbonate on Decomposition of Formic Acid by Discharge inside Bubble in Water

    NASA Astrophysics Data System (ADS)

    Iwabuchi, Masashi; Takahashi, Katsuyuki; Takaki, Koichi; Satta, Naoya

    2015-09-01

    An influence of sodium carbonate on decomposition of formic acid by discharge inside bubble in water was investigated. Oxygen or argon gases were injected into the water through a vertically positioned glass tube, in which the high-voltage wire electrode was placed to generate plasmas at low applied voltage. The concentration of formic acid was determined by ion chromatography. In the case of addition of sodium carbonate, the pH value increased with decomposition of the formic acid. In the case of oxygen injection, the increase of pH value contributed to improve an efficiency of the formic acid decomposition because the reaction rate of ozone and formic acid increased with increasing pH value. In the case of argon injection, the decomposition rate was not affected by the pH value owing to the high rate constants for loss of hydroxyl radicals.

  3. Habitat use by a Midwestern U.S.A. riverine fish assemblage: effects of season, water temperature and river discharge

    USGS Publications Warehouse

    Gillette, D.P.; Tiemann, J.S.; Edds, D.R.; Wildhaber, M.L.

    2006-01-01

    The hypothesis that temperate stream fishes alter habitat use in response to changing water temperature and stream discharge was evaluated over a 1 year period in the Neosho River, Kansas, U.S.A. at two spatial scales. Winter patterns differed from those of all other seasons, with shallower water used less frequently, and low-flow habitat more frequently, than at other times. Non-random habitat use was more frequent at the point scale (4.5 m2) than at the larger reach scale (20-40 m), although patterns at both scales were similar. Relative to available habitats, assemblages used shallower, swifter-flowing water as temperature increased, and shallower, slower-flowing water as river discharge increased. River discharge had a stronger effect on assemblage habitat use than water temperature. Proportion of juveniles in the assemblage did not have a significant effect. This study suggests that many riverine fishes shift habitats in response to changing environmental conditions, and supports, at the assemblage level, the paradigm of lotic fishes switching from shallower, high-velocity habitats in summer to deeper, low-velocity habitats in winter, and of using shallower, low-velocity habitats during periods of high discharge. Results also indicate that different species within temperate river fish assemblages show similar habitat use patterns at multiple scales in response to environmental gradients, but that non-random use of available habitats is more frequent at small scales. ?? 2006 The Fisheries Society of the British Isles.

  4. Produced water discharges to the Gulf of Mexico: Background information for ecological risk assessments

    SciTech Connect

    Meinhold, A.F.; Holtzman, S.; DePhillips, M.P.

    1996-06-01

    This report reviews ecological risk assessment concepts and methods; describes important biological resources in the Gulf of Mexico of potential concern for produced water impacts; and summarizes data available to estimate exposure and effects of produced water discharges. The emphasis is on data relating to produced water discharges in the central and western Gulf of Mexico, especially in Louisiana. Much of the summarized data and cited literature are relevant to assessments of impacts in other regions. Data describing effects on marine and estuarine fishes, mollusks, crustaceans and benthic invertebrates are emphasized. This review is part of a series of studies of the health and ecological risks from discharges of produced water to the Gulf of Mexico. These assessments will provide input to regulators in the development of guidelines and permits, and to industry in the use of appropriate discharge practices.

  5. Requiring pollutant discharge permits for pesticide applications that deposit residues in surface waters.

    PubMed

    Centner, Terence; Eberhart, Nicholas

    2014-05-01

    Agricultural producers and public health authorities apply pesticides to control pests that damage crops and carry diseases. Due to the toxic nature of most pesticides, they are regulated by governments. Regulatory provisions require pesticides to be registered and restrictions operate to safeguard human health and the environment. Yet pesticides used near surface waters pose dangers to non-target species and drinking water supplies leading some governments to regulate discharges of pesticides under pollution discharge permits. The dual registration and discharge permitting provisions are burdensome. In the United States, agricultural interest groups are advancing new legislation that would exempt pesticide residues from water permitting requirements. An analysis of the dangers posed by pesticide residues in drinking water leads to a conclusion that both pesticide registration and pollutant discharge permitting provisions are needed to protect human health and aquatic species. PMID:24814945

  6. Requiring Pollutant Discharge Permits for Pesticide Applications that Deposit Residues in Surface Waters

    PubMed Central

    Centner, Terence; Eberhart, Nicholas

    2014-01-01

    Agricultural producers and public health authorities apply pesticides to control pests that damage crops and carry diseases. Due to the toxic nature of most pesticides, they are regulated by governments. Regulatory provisions require pesticides to be registered and restrictions operate to safeguard human health and the environment. Yet pesticides used near surface waters pose dangers to non-target species and drinking water supplies leading some governments to regulate discharges of pesticides under pollution discharge permits. The dual registration and discharge permitting provisions are burdensome. In the United States, agricultural interest groups are advancing new legislation that would exempt pesticide residues from water permitting requirements. An analysis of the dangers posed by pesticide residues in drinking water leads to a conclusion that both pesticide registration and pollutant discharge permitting provisions are needed to protect human health and aquatic species. PMID:24814945

  7. Model-estimated ground-water recharge and hydrograph of ground-water discharge to a stream

    USGS Publications Warehouse

    Rutledge, A.T.

    1997-01-01

    The computer model PULSE, described in this report, can be used to construct a hydrograph of ground-water discharge to a stream. The model is applicable to a ground-water flow system that is driven by areally uniform recharge to the water table, and in which ground water discharges to a gaining stream. One of the two formulations used by the model allows for an instantaneous recharge pulse and subsequent ground-water discharge to the stream. The other formulation, which allows for a gradual hydrologic gain or loss term in addition to the instantaneous pulse, can be used to simulate the effects of gradual recharge to the water table, ground-water evapotranspiration, or downward leakage to a deeper aquifer.

  8. Potential water-quality effects of coal-bed methane production water discharged along the upper Tongue River, Wyoming and Montana

    USGS Publications Warehouse

    Kinsey, Stacy M.; Nimick, David A.

    2011-01-01

    Water quality in the upper Tongue River from Monarch, Wyoming, downstream to just upstream from the Tongue River Reservoir in Montana potentially could be affected by discharge of coal-bed methane (CBM) production water (hereinafter referred to as CBM discharge). CBM discharge typically contains high concentrations of sodium and other ions that could increase dissolved-solids (salt) concentrations, specific conductance (SC), and sodium-adsorption ratio (SAR) in the river. Increased inputs of sodium and other ions have the potential to alter the river's suitability for agricultural irrigation and aquatic ecosystems. Data from two large tributaries, Goose Creek and Prairie Dog Creek, indicate that these tributaries were large contributors to the increase in SC and SAR in the Tongue River. However, water-quality data were not available for most of the smaller inflows, such as small tributaries, irrigation-return flows, and CBM discharges. Thus, effects of these inflows on the water quality of the Tongue River were not well documented. Effects of these small inflows might be subtle and difficult to determine without more extensive data collection to describe spatial patterns. Therefore, synoptic water-quality sampling trips were conducted in September 2005 and April 2006 to provide a spatially detailed profile of the downstream changes in water quality in this reach of the Tongue River. The purpose of this report is to describe these downstream changes in water quality and to estimate the potential water-quality effects of CBM discharge in the upper Tongue River. Specific conductance of the Tongue River through the study reach increased from 420 to 625 microsiemens per centimeter (.μS/cm; or 49 percent) in the downstream direction in September 2005 and from 373 to 543 .μS/cm (46 percent) in April 2006. Large increases (12 to 24 percent) were measured immediately downstream from Goose Creek and Prairie Dog Creek during both sampling trips. Increases attributed to

  9. Experimental measurement of spatially resolved electron density in a filament of a pulsed positive streamer discharge in water

    SciTech Connect

    Wen, Xiao Qiong; Niu, Zhi Wen; Ren, Chun-Sheng; Hou, Bo

    2015-06-29

    By combining a high-speed frame camera with a monochromator, the spatially resolved optical emission spectrum of hydrogen α line in a single filament of a pulsed positive streamer discharge in water has been experimentally measured. The spatially resolved electron densities in a single filament of a pulsed positive streamer discharge in water with a conductivity of 200 μS/cm were investigated. During the experiment, the average energy per pulse of discharge was 90.6 ± 13.6 mJ. The results show that the electron density in the streamer filament is 10{sup 17–18}/cm{sup 3}, and present a decreasing tendency along the axial direction of the streamer filament with increasing distance from the tip of the anode.

  10. Heated Discharge Control and Management Alternatives: Small Water Bodies and Rivers.

    ERIC Educational Resources Information Center

    MacLaren, James F.

    Basic concepts of waste heat management on shallow and deep small water bodies and rivers are reviewed and examples are given. This study defines a small water body as a body in which the far field hydrothermal effects of a heated discharge can be detected in a major portion or practically all of the water body. Environmental effects due to…

  11. Ground-water discharge and nitrate loadings to the coastal bays of Maryland

    USGS Publications Warehouse

    Dillow, Jonathan J.A.; Greene, Earl A.

    1999-01-01

    Nitrate in ground water discharged to the Atlantic coastal bays of Maryland enhances the growth of phytoplankton and algae in the bays, which in turn contributes to the process of eutrophication (changes in a body of water as nutrients and sediments accumulate), which is one of the principal environmental problems in the bays. Information on nitrate loading to the bays has been identified as a major data gap by State and Federal resource managers. This report presents results of a study to estimate ground-water discharge and potential nitrate loads to the coastal bays of Maryland, which include Chincoteague, Newport, Sinepuxent, Isle of Wight, and Assawoman Bays. The nitrate load from the discharge of ground water to the coastal bays is dependent on the concentration of nitrate in the water and the volume of ground water being discharged. Data from 388 wells completed in the surficial aquifer that discharges to the bays were used to construct a map of the distribution of nitrate concentration in the ground water. On the basis of those data, and on several simplifying assumptions, the potential nitrate load to the coastal bays from direct discharge of ground water was estimated to be 272,000 pounds of nitrate per year, distributed throughout the 108-square-mile surface area of the bays. Nitrate from ground water can also enter the coastal bays by way of base flow to streams that discharge to the bays. The potential nitrate load to the bays from the base flow of streams was estimated to be 862,000 pounds per year, assuming that the concentration of nitrate in stream base flow is 3.2 milligrams per liter, which is the median concentration of nitrate in ground water in the study area.

  12. Electrodeless HID lamp study. Final report. [High intensity discharge

    SciTech Connect

    Anderson, J.M.; Johnson, P.D.; Jones, C.E.; Rautenberg, T.H.

    1985-01-01

    High intensity discharge lamps excited by solenoidal electric fields (SEF/HID) were examined for their ability to give high brightness, high efficacy and good color. Frequency of operation was 13.56 MHz (ISM Band) and power to the lamp plasma ranged from about 400 to 1000 W. Radio frequency transformers with air cores and with air core complemented by ferrite material in the magnetic path were used to provide the voltage for excitation. Electrical properties of the matching network and the lamp plasma were measured or calculated and total light from the lamp was measured by an integrating sphere. Efficacies calculated from measurement were found to agree well with the positive column efficacies of conventional HID lamps containing only mercury, and with additives of sodium, thallium, and scandium iodide. Recommendations for future work are given.

  13. Estimates of Nutrient Loading by Ground-Water Discharge into the Lynch Cove Area of Hood Canal, Washington

    USGS Publications Warehouse

    Simonds, F. William; Swarzenski, Peter W.; Rosenberry, Donald O.; Reich, Christopher D.; Paulson, Anthony J.

    2008-01-01

    field investigations show that ground-water discharge into the Lynch Cove area of Hood Canal is highly dynamic and strongly affected by the large tidal range. In areas with a steep shoreline and steep hydraulic gradient, ground-water discharge is spatially concentrated in or near the intertidal zone, with increased discharge during low tide. Topographically flat areas with weak hydraulic gradients had more spatial variability, including larger areas of seawater recirculation and more widely dispersed discharge. Measured total-dissolved-nitrogen concentrations in ground water ranged from below detection limits to 2.29 milligrams per liter and the total load entering Lynch Cove was estimated to be approximately 98 ? 10.3 metric tons per year (MT/yr). This estimate is based on net freshwater seepage rates from Lee-type seepage meter measurements and can be compared to estimates derived from geochemical tracer mass balance estimates (radon and radium) of 231 to 749 MT/yr, and previous water-mass-balance estimates (14 to 47 MT/ yr). Uncertainty in these loading estimates is introduced by complex biogeochemical cycles of relevant nutrient species, the representativeness of measurement sites, and by energetic dynamics at the coastal aquifer-seawater interface caused by tidal forcing.

  14. Suspended sediment and stream discharge in Bloody Run and Sny Magill watershed, water year 1992

    USGS Publications Warehouse

    Kalkhoff, Stephen J.; Eash, David A.

    1994-01-01

    Hydrologic data were collected in the Bloody Run and Sny Magill watersheds in Clayton County, Iowa during the 1992 Water Year (October 1, 1991 to September 30, 1992) to provide data on suspended sediment and stream discharge from these watersheds.  Suspended-sediment samples were collected daily during normal flow and several times during rainstorms.  Stream stage was recorded continuously and stream-discharge measurements were made monthly to develop a stage-discharge relation.  Data on drainage-basin morphology and precipitation were quantified to help understand the variability in sediment and stream discharge.  The total suspended-sediment discharge for Water Year 1992 was 2,720 tons at site BR1 on Bloody Run and 1,940 tons at site SN1 on Sny Magill Creek  The daily median suspended-sediment discharge was 1.1 tons at both sites BR1 and SN1.  The maximum daily mean stream discharge (205 cubic feet per second) at site BR1 on Bloody Run occurred on November 1, 1991.  The median daily discharge at BR1 for the 1992 Water year was 24 cubic feet per second or 0.70 cubic feet per second per square mile (ft3/s/mi2).  The maximum daily mean stream discharge at site SN1 on Sny Magill Creek was 90 cubic feet per second which occurred on April 20, 1992.  The median daily discharge at site SN1 for the 1992 Water Year was 15 cubic feet per second or 0.54 ft3/s/mi2.

  15. Pathogenic and nonpathogenic Acanthamoeba spp. in thermally polluted discharges and surface waters

    SciTech Connect

    de Jonckheere, J.F.

    1981-02-01

    During spring and autumn, the total number of amoebae and the number of acanthamoeba species able to grow at 37 degrees C were determined in six thermally polluted factory discharges and the surrounding surface waters. The isolated Acanthamoeba strains were studied for growth in axenic medium, cytopathic effect in Vito cell cultures, and virulence in mice. Although more amoebae were isolated in autumn, the number of Acanthamoeba species was lower than in spring, when the percent of pathogenic strains among the isolates was highest. Higher concentrations of amoebae were found in warm discharges, and more virulent strains occurred in thermal discharges than in surface waters.

  16. Estimates of ground-water discharge as determined from measurements of evapotranspiration, Ash Meadows area, Nye County, Nevada

    USGS Publications Warehouse

    Laczniak, R.J.; DeMeo, G.A.; Reiner, S.R.; Smith, Jody L.; Nylund, W.E.

    1999-01-01

    of the seven identified ET units. Micrometeorological data were collected for a minimum of 1 year at each site during 1994 through 1997. Evapotranspiration ranged from 0.6 foot per year in a sparse, dry saltgrass environment to 8.6 feet per year over open water. Ancillary data, including water levels, were collected during this same period to gain additional insight into the evapotranspiration process. Water levels measured in shallow wells showed annual declines of more than 10 feet and daily declines as high as 0.3 foot attributed to water losses associated with evapotranspiration. Mean annual ET from the Ash Meadows area is estimated at 21,000 acre-feet. An estimate of ground-water discharge, based on this ET estimate, is presented as a range to account for uncertainties in the contribution of local precipitation. The estimates given for mean annual ground-water discharge range from 18,000 to 21,000 acre-feet. The low estimate assumes a large contribution from local precipitation in computed ET rates; whereas, the high estimate assumes no contribution from local precipitation. The range presented is only slightly higher than previous estimates of ground-water discharge from the Ash Meadows area based primarily on springflow measurements.

  17. An investigation of an underwater steam plasma discharge as alternative to air plasmas for water purification

    NASA Astrophysics Data System (ADS)

    Gucker, Sarah N.; Foster, John E.; Garcia, Maria C.

    2015-10-01

    An underwater steam plasma discharge, in which water itself is the ionizing media, is investigated as a means to introduce advanced oxidation species into contaminated water for the purpose of water purification. The steam discharge avoids the acidification observed with air discharges and also avoids the need for a feed gas, simplifying the system. Steam discharge operation did not result in a pH changes in the processing of water or simulated wastewater, with the actual pH remaining roughly constant during processing. Simulated wastewater has been shown to continue to decompose significantly after steam treatment, suggesting the presence of long-lived plasma produced radicals. During steam discharge operation, nitrate production is limited, and nitrite production was found to be below the detection threshold of (roughly 0.2 mg L-1). The discharge was operated over a broad range of deposited power levels, ranging from approximately 30 W to 300 W. Hydrogen peroxide production was found to scale with increasing power. Additionally, the hydrogen peroxide production efficiency of the discharge was found to be higher than many of the rates reported in the literature to date.

  18. Magnetic shielding of Hall thrusters at high discharge voltages

    SciTech Connect

    Mikellides, Ioannis G. Hofer, Richard R.; Katz, Ira; Goebel, Dan M.

    2014-08-07

    A series of numerical simulations and experiments have been performed to assess the effectiveness of magnetic shielding in a Hall thruster operating in the discharge voltage range of 300–700 V (I{sub sp} ≈ 2000–2700 s) at 6 kW, and 800 V (I{sub sp} ≈ 3000) at 9 kW. At 6 kW, the magnetic field topology with which highly effective magnetic shielding was previously demonstrated at 300 V has been retained for all other discharge voltages; only the magnitude of the field has been changed to achieve optimum thruster performance. It is found that magnetic shielding remains highly effective for all discharge voltages studied. This is because the channel is long enough to allow hot electrons near the channel exit to cool significantly upon reaching the anode. Thus, despite the rise of the maximum electron temperature in the channel with discharge voltage, the electrons along the grazing lines of force remain cold enough to eliminate or reduce significantly parallel gradients of the plasma potential near the walls. Computed maximum erosion rates in the range of 300–700 V are found not to exceed 10{sup −2} mm/kh. Such rates are ∼3 orders of magnitude less than those observed in the unshielded version of the same thruster at 300 V. At 9 kW and 800 V, saturation of the magnetic circuit did not allow for precisely the same magnetic shielding topology as that employed during the 6-kW operation since this thruster was not designed to operate at this condition. Consequently, the maximum erosion rate at the inner wall is found to be ∼1 order of magnitude higher (∼10{sup −1} mm/kh) than that at 6 kW. At the outer wall, the ion energy is found to be below the sputtering yield threshold so no measurable erosion is expected.

  19. 77 FR 35268 - Standards for Living Organisms in Ships' Ballast Water Discharged in U.S. Waters

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-13

    ... concentration of living organisms in ships' ballast water discharged in waters of the United States (77 FR 17254). The Coast Guard also established an approval process for ballast water management systems (77 FR 17254... SECURITY Coast Guard 33 CFR Part 151 46 CFR Part 162 RIN 1625-AA32 Standards for Living Organisms in...

  20. High Rate Discharge Studies of LI/SO2 Batteries

    NASA Technical Reports Server (NTRS)

    Barnes, J. A.; Buchholz, S.; Bis, R. F.; Debold, F. C.; Kowalchik, L. A.

    1984-01-01

    A battery composed of twelve lithium/sulfur dioxide D size cells in series is forced discharged at 21 amperes. This current is established by the proposed use of the battery and represented a discharge condition which might produce venting. Discharge of the battery into voltage reversal results not only in cells venting but also in the violent rupture of at least one cell.

  1. Global model for high pressure electronegative radio-frequency discharges

    SciTech Connect

    Lee, Y.T.; Lieberman, M.A.; Lichtenberg, A.J.; Bose, F.; Baltes, H.; Patrick, R.

    1997-01-01

    We develop a global model for high pressure (0.1{endash}1 Torr) electronegative rf discharges and apply it to model a capacitively driven plasma etcher. The molecular gases considered consist of either pure chlorine species or a mixture of chlorine and helium species. The charged and neutral heavy particle densities together with the electron density and electron temperature are calculated by using the equations of particle balance and power balance for the input discharge parameters rf power or rf current, inlet pressure, gas flow rates, reactor diameter, and gap spacing. The power is deposited in the electrons via ohmic heating and in those ions accelerated across the dc sheath potential. The voltage across the sheath is calculated self-consistently with the densities and the electron temperature by using a collisional Child law sheath model. Analytic scaling laws for the dependence of charged and neutral particle densities, electron temperature, rf voltage and current, sheath width, and plasma impedance on pressure and absorbed rf power are presented and used to explain the numerical results obtained from the global model. The model results are compared to recent experimental measurements in a chlorine discharge over a range of absorbed power P{sub abs}=20{endash}180W at an inlet pressure p{sub in}=0.4 Torr and a range of pressure 0.1{endash}1.6 Torr with a fixed input power of 100 W. We obtain reasonable agreement for P{sub abs}{lt}200W and for 0.2 Torr{lt}p{sub in}{lt}1Torr. {copyright} {ital 1997 American Vacuum Society.}

  2. RF physics of ICWC discharge at high cyclotron harmonics

    NASA Astrophysics Data System (ADS)

    Lyssoivan, A.; van Eester, D.; Wauters, T.; Bobkov, V.; Vervier, M.; Douai, D.; Kogut, D.; Kreter, A.; Moiseenko, V.; Möller, S.; Noterdaeme, J.-M.; Philipps, V.; Rohde, V.; Schneider, P.; Sergienko, G.; van Schoor, M.; Textor Team, ASDEX Upgrade Team

    2014-02-01

    Recent experiments on Ion Cyclotron Wall Conditioning (ICWC) performed in tokamaks TEXTOR and ASDEX Upgrade with standard ICRF antennas operated at fixed frequencies but variable toroidal magnetic field demonstrated rather contrasting parameters of ICWC discharge in scenarios with on-axis fundamental ion cyclotron resonance (ICR) for protons,ω=ωH+, and with its high cyclotron harmonics (HCH), ω=10ωcH+ṡ HCH scenario: very high antenna coupling to low density RF plasmas (Ppl≈0.9PRF-G) and low energy Maxwellian distribution of CX hydrogen atoms with temperature TH≈350 eV. Fundamental ICR: lower antenna-plasma coupling efficiency (by factor of about 1.5 times) and generation of high energy non-Maxwellian CX hydrogen atoms (with local energy E⊥H ≥1.0 keV). In the present paper, we analyze the obtained experimental results numerically using (i) newly developed 0-D transport code describing the process of plasma production with electron and ion collisional ionization in helium-hydrogen gas mixture and (ii) earlier developed 1-D Dispersion Relation Solver accounting for finite temperature effects and collision absorption mechanisms for all plasma species in addition to conventionally examined Landau/TTPM damping for electrons and cyclotron absorption for ions. The numerical study of plasma production in helium with minor hydrogen content in low and high toroidal magnetic fields is presented. The investigation of the excitation, conversion and absorption of plasma waves as function of BT-field suggests that only fast waves (FW) may give a crucial impact on antenna coupling and characteristics of the ICWC discharge using standard poloidally polarized ICRF antennas designed to couple RF power mainly to FW. The collisional (non-resonant) absorption by electrons and ions and IC absorption by resonant ions of minor concentration in low Te plasmas is studied at fundamental ICR and its high harmonics.

  3. Characterization of fish hold effluent discharged from commercial fishing vessels into harbor waters.

    PubMed

    Albert, Ryan J; McLaughlin, Christine; Falatko, Debra

    2014-10-15

    Fish hold effluent and the effluent produced from the cleaning of fish holds may contain organic material resulting from the degradation of seafood and cleaning products (e.g., soaps and detergents). This effluent is often discharged by vessels into near shore waters and, therefore, could have the potential to contribute to water pollution in bays and estuaries. We characterized effluent from commercial fishing vessels with holds containing refrigerated seawater, ice slurry, or chipped ice. Concentrations of trace heavy metals, wet chemistry parameters, and nutrients in effluent were compared to screening benchmarks to determine if there is a reasonable potential for effluent discharge to contribute to nonattainment of water quality standards. Most analytes (67%) exceeded their benchmark concentration and, therefore, may have the potential to pose risk to human health or the environment if discharges are in significant quantities or there are many vessels discharging in the same areas. PMID:25176279

  4. Effects of high salinity wastewater discharges on unionid mussels in the Allegheny River, Pennsylvania

    USGS Publications Warehouse

    Kathleen Patnode; Hittle, Elizabeth A.; Robert Anderson; Lora Zimmerman; Fulton, John W.

    2015-01-01

    We examined the effect of high salinity wastewater (brine) from oil and natural gas drilling on freshwater mussels in the Allegheny River, Pennsylvania, during 2012. Mussel cages (N = 5 per site) were deployed at two sites upstream and four sites downstream of a brine treatment facility on the Allegheny River. Each cage contained 20 juvenile northern riffleshell mussels Epioblasma torulosa rangiana). Continuous specific conductance and temperature data were recorded by water quality probes deployed at each site. To measure the amount of mixing throughout the entire study area, specific conductance surveys were completed two times during low-flow conditions along transects from bank to bank that targeted upstream (reference) reaches, a municipal wastewater treatment plant discharge upstream of the brine-facility discharge, the brine facility, and downstream reaches. Specific conductance data indicated that high specific conductance water from the brine facility (4,000–12,000 µS/cm; mean 7,846) compared to the reference reach (103–188 µS/cm; mean 151) is carried along the left descending bank of the river and that dilution of the discharge via mixing does not occur until 0.5 mi (805 m) downstream. Juvenile northern riffleshell mussel survival was severely impaired within the high specific conductance zone (2 and 34% at and downstream of the brine facility, respectively) and at the municipal wastewater treatment plant (21%) compared to background (84%). We surveyed native mussels (family Unionidae) at 10 transects: 3 upstream, 3 within, and 4 downstream of the high specific conductance zone. Unionid mussel abundance and diversity were lower for all transects within and downstream of the high conductivity zone compared to upstream. The results of this study clearly demonstrate in situ toxicity to juvenile northern riffleshell mussels, a federally endangered species, and to the native unionid mussel assemblage located downstream of a brine discharge to the

  5. Role of water and discharge mode on modulating properties in an atmospheric air MHCD jet

    NASA Astrophysics Data System (ADS)

    Liu, Kun; Wang, Chenying; Lei, Juzhang; Hu, Huimin; Zheng, Peichao; He, Wei

    2016-04-01

    A portable micro hollow cathode discharge (MHCD) device was designed in this paper to generate water-air plasma jet. The results showed that MHCD jet pattern was changed from self-pulsing discharge mode to DC mode with the increasing of voltage, and the critical voltage value of discharge mode increased with the rise of gas flow. In order to study the influences of discharge mode and water content on MHCD jet, the electrical characteristics and radicals were all measured in different conditions. We found that the length of jet decreased and temperature increased with raising water-air ratio, and during self-pulsing discharge mode, •OH content was extremely low because of the low energy of electron, but level of NO was raised with gradually increasing applied voltage. In DC mode, the results showed there was least NO content, on the other hand •OH content increased with rise of voltage and water-air ratio. O existed in both discharge modes and the effect of water content on the O production was complex. Contribution to the Topical Issue "Recent Breakthroughs in Microplasma Science and Technology", edited by Kurt Becker, Jose Lopez, David Staack, Klaus-Dieter Weltmann and Wei Dong Zhu.

  6. Evaluation of the potentials of humic acid removal in water by gas phase surface discharge plasma.

    PubMed

    Wang, Tiecheng; Qu, Guangzhou; Ren, Jingyu; Yan, Qiuhe; Sun, Qiuhong; Liang, Dongli; Hu, Shibin

    2016-02-01

    Degradation of humic acid (HA), a predominant type of natural organic matter in ground water and surface waters, was conducted using a gas phase surface discharge plasma system. HA standard and two surface waters (Wetland, and Weihe River) were selected as the targets. The experimental results showed that about 90.9% of standard HA was smoothly removed within 40 min's discharge plasma treatment at discharge voltage 23.0 kV, and the removal process fitted the first-order kinetic model. Roles of some active species in HA removal were studied by evaluating the effects of solution pH and OH radical scavenger; and the results presented that O3 and OH radical played significant roles in HA removal. Scanning electron microscope (SEM) and FTIR analysis showed that HA surface topography and molecular structure were changed during discharge plasma process. The mineralization of HA was analyzed by UV-Vis spectrum, dissolved organic carbon (DOC), specific UV absorbance (SUVA), UV absorption ratios, and excitation-emission matrix (EEM) fluorescence. The formation of disinfection by-products during HA sample chlorination was also identified, and CHCl3 was detected as the main disinfection by-product, but discharge plasma treatment could suppress its formation to a certain extent. In addition, approximately 82.3% and 67.9% of UV254 were removed for the Weihe River water and the Wetland water after 40 min of discharge plasma treatment. PMID:26624519

  7. 21 CFR 1040.30 - High-intensity mercury vapor discharge lamps.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false High-intensity mercury vapor discharge lamps. 1040...-intensity mercury vapor discharge lamps. (a) Applicability. The provisions of this section apply to any high-intensity mercury vapor discharge lamp that is designed, intended, or promoted for illumination purposes...

  8. 21 CFR 1040.30 - High-intensity mercury vapor discharge lamps.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false High-intensity mercury vapor discharge lamps. 1040...-intensity mercury vapor discharge lamps. (a) Applicability. The provisions of this section apply to any high-intensity mercury vapor discharge lamp that is designed, intended, or promoted for illumination purposes...

  9. 21 CFR 1040.30 - High-intensity mercury vapor discharge lamps.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false High-intensity mercury vapor discharge lamps. 1040...-intensity mercury vapor discharge lamps. (a) Applicability. The provisions of this section apply to any high-intensity mercury vapor discharge lamp that is designed, intended, or promoted for illumination purposes...

  10. Ionization front in a high-current gas discharge

    NASA Astrophysics Data System (ADS)

    Choueiri, Edgar Y.; Randolph, Thomas M.

    2007-02-01

    Spectroscopic measurements of ion/neutral density ratio profiles are made inside the high-current, low-pressure discharge of a coaxial magnetoplasmadynamic thruster and show the existence of a thin ionization front, upstream in the discharge, that effectively ionizes the incoming gas to ionization levels above 50%. The measurements allow an estimate of the width of this ionization front to be on the order of a few millimeters. Due to the known existence of microturbulence in the plasma, which can produce suprathermal electrons, an explanation of the measurements based on the existence of a suprathermal tail in the electron energy distribution function is sought. A theoretical model for the width of the ionization front is combined with a multilevel excitation model for argon and shows that a Maxwellian electron distribution function cannot account for the small length scale of the ionization front, and that the latter is more consistent with an electron distribution function having a suprathermal population, the magnitude of which is estimated by comparing the model to the experiments.

  11. Ionization front in a high-current gas discharge

    SciTech Connect

    Choueiri, Edgar Y.; Randolph, Thomas M.

    2007-03-15

    Spectroscopic measurements of ion/neutral density ratio profiles are made inside the high-current, low-pressure discharge of a coaxial magnetoplasmadynamic thruster and show the existence of a thin ionization front, upstream in the discharge, that effectively ionizes the incoming gas to ionization levels above 50%. The measurements allow an estimate of the width of this ionization front to be on the order of a few millimeters. Due to the known existence of microturbulence in the plasma, which can produce suprathermal electrons, an explanation of the measurements based on the existence of a suprathermal tail in the electron energy distribution function is sought. A theoretical model for the width of the ionization front is combined with a multilevel excitation model for argon and shows that a Maxwellian electron distribution function cannot account for the small length scale of the ionization front, and that the latter is more consistent with an electron distribution function having a suprathermal population, the magnitude of which is estimated by comparing the model to the experiments.

  12. Pulsed positive streamer discharges in air at high temperatures

    NASA Astrophysics Data System (ADS)

    Ono, Ryo; Kamakura, Taku

    2016-08-01

    Atmospheric-pressure air pulsed positive streamer discharges are generated in a 13 mm point-plane gap in the temperature range of 293 K–1136 K, and the effect of temperature on the streamer discharges is studied. When the temperature is increased, the product of applied voltage and temperature VT proportional to the reduced electric field can be used as a primary parameter that determines some discharge parameters regardless of temperature. For a given VT, the transferred charge per pulse, streamer diameter, product of discharge energy and temperature, and length of secondary streamer are almost constant regardless of T, whereas the streamer velocity decreases with increasing T and the decay rate of the discharge current is proportional to 1/T. The N2(C) emission intensity is approximately determined by the discharge energy independent of T. These results are useful to predict the streamer discharge and its reactive species production when the ambient temperature is increased.

  13. USDOE study: Human health and ecological risk assessment for produced water discharges

    SciTech Connect

    Meinhold, A.F.; Holtzman, S.; DePhillips, M.; Hamilton, L.D.

    1994-12-31

    Produced water generated during the production of oil and gas can contain high concentrations of radionuclides, organics and heavy metals. There are concerns about potential human health and ecological impacts from the discharge of these contaminants to the Gulf of Mexico. Data collected in the United States Department of Energy (USDOE) field study are being used in a series of human health and ecological risk assessments. These assessments will support scientifically-based regulation and risk management. This presentation: summarizes risk assessments performed for produced water discharges; describes how uncertainties in these assessments are guiding data collection efforts in the USDOE field study; and outlines ongoing risk assessment studies. In these studies, risk assessment is treated as an iterative process. An initial screening-level assessment is performed to identify important contaminants, transport and exposure pathways, and parameters. These intermediate results are used to guide data collection efforts and refinements to the analysis. At this stage in the analysis, risk is described in terms of probabilities; the uncertainties in each measured or modeled parameter are considered explicitly.

  14. Spatial and temporal distributions of toxicity in receiving waters around an oil effluent discharge site

    SciTech Connect

    Krause, P.R.

    1994-12-31

    Distributions of pollutants from a point source discharge within the water column may vary in both time and space. In this study, they examined the spatial and temporal patterns of toxicity from an oil production effluent (produced water) discharge plume using sea urchin fertilization and development bioassays. Specifically, they tested the sensitivity and response patterns of sea urchin gametes and early life stages exposed to receiving waters sampled along a 1 km transact near an active produced water outfall. Fertilization success and development of larvae to the pluteus stage varied significantly with proximity to the outfall, with reduced fertilization and larval development found closer to the outfall. Although estimated toxicity in receiving water samples, based on fertilization success, was variable in time -- perhaps responding to variation in the quantity or make-up of produced water discharges -- the general spatial pattern of toxicity along the sampling transact remained relatively constant. Strong evidence that field toxicity was directly attributable to produced water effluents was provided by sampling the receiving waters while the produced water discharge was not operating. At such a time, no toxicity was found at any of the field sites. Receiving water toxicity data, along with toxicity data from the effluent itself, were used to prepare a ``map`` of effective effluent concentrations along the sampling transect.

  15. Best Management Practices (BMP) plan for potable water discharges Y-12 Plant

    SciTech Connect

    Wiest, M.C. Jr.

    1995-07-01

    This plan provides guidance to minimize the environmental effects from discharges of chlorinated waters, including: Flushing of potable water lines; Releases from fire hydrants during testing and maintenance of fire protection systems; Releases from sprinkler systems for maintenance or testing purposes; and Other significant releases of chlorinated water. This BMP plan is intended to meet the Y-12 Plant National Pollutant Discharge Elimination System (NPDES) permit condition, requiring that BWs be used for flushing potable water lines and similar activities. Close adherence to the steps provided in this plan will help prevent the discharge of chlorinated waters ``in concentrations sufficient to be hazardous or otherwise detrimental to humans, livestock, wildlife, plant life, or fish and aquatic life in the receiving stream``.

  16. Temporal variability of the non-steady contribution from glaciers to water discharge in western Austria

    NASA Astrophysics Data System (ADS)

    Lambrecht, Astrid; Mayer, Christoph

    2009-10-01

    SummaryA long series of negative glacier mass balance years during the last decades influenced the run-off characteristics of glacierized catchments in the Austrian Alps. For balanced conditions, run-off from catchments containing glaciers shows increased values for warm and dry periods, but the annual sum generally equals the total basin precipitation. In contrast, the recent series of negative glacier mass balances reduced the storage volume of the glaciers, providing additional water in the rivers for many years. The existing Austrian Glacier Inventories allowed the determination of very accurate glacier volume changes between 1969 and 1998. These data were used to calculate the excess discharge for two catchment basins in western Austria (one unaffected by hydro power management, one with hydropower management) for the time period between the inventories which then was compared to the accumulated river run-off from the individual basins. The inter-annual distribution of the total excess could be determined by using existing mass balance series from several glaciers in the different basins as scaling functions. In addition, a degree-day approach was used to provide information about the role of above-average glacial melt water on a monthly basis. Considering different gauging stations along the rivers, it was found that the amount of excess discharge during the entire period was in the range of 1.5-9% of the total discharge, depending on the relative degree of glacier coverage (4-40%). For summer months only, this fraction increases to 3-12%. In individual months, however, the relative importance of excess melt can reach more than 25% in a highly glacier covered catchment (40%), but it can also contribute up to 20% for catchments with a glacier coverage of 8-15%.

  17. Ground water discharge by evapotranspiration in wetlands of an arid intermountain basin

    NASA Astrophysics Data System (ADS)

    Sanderson, John S.; Cooper, David J.

    2008-04-01

    SummaryTo improve basin-scale modeling of ground water discharge by evapotranspiration (ET) in relation to water table depth, daily ET was measured using the Bowen ratio energy balance method during 1999-2005 in five herbaceous plant dominated wetlands in an arid intermountain basin in Colorado, USA. Three wetlands were wet meadows supplied primarily by regional ground water flow and two were playas supplied primarily by local stream flow. In wet meadows, mean daily water table depth (WTD) ranged from 0.00 m (ground surface) to 1.2 m, with low inter-annual variability. In wet meadows, annual actual ET (ET a) was 751-994 mm, and ground water discharge from the shallow aquifer (ET g) was 75-88% of ET a. In playas, mean daily WTD ranged from -0.65 to 1.89 m, with high inter-annual variability. In playas, annual ET a was 352-892 mm, and ET g was 0-77% of ET a. The relationship of annual ET g to WTD was compared to existing ET g-WTD models. For wet meadows, ET g decreased exponentially as WTD increased from 0.13 to 0.95 m ( r2 = 0.83, CV = 5%, p < 0.001). In comparison with our findings, existing models under- and over-estimate ET g by -30% to 47% at WTD of 0.13 m, and they under-estimate ET g by -12% to -42% at WTD of 0.95 m. This study found that as the water table declined from near the soil surface to 0.95 m, ET g decreased only ˜26% versus 39-55% estimated by existing models. The magnitude of ET g decrease was 220 mm, whereas existing models predicted decreases up to 700 mm (218% greater). In playas, there was no clear ET g-WTD relationship. Instead, ET g was strongly dependent on the surface water supply. When sufficient surface water inputs occurred to meet ET demand, ET g was ≈0 mm/yr and independent of WTD. When inputs did not meet ET demand, ET g was positive though highly variable at WTD up to 1.68 m.

  18. Mineral water discharges at the Azores archipelago (Portugal): hydrogeological setting, chemical composition and mapping

    NASA Astrophysics Data System (ADS)

    Freire, P.; Cruz, J.; Coutinho, R.; Costa, A.; Antunes, P.

    2009-04-01

    The geological setting of the Azores archipelago, located in the North Atlantic ocean, about 1500 km form Portugal mainland and made of 9 islands of volcanic origin, enhances the multiplicity of surface hydrothermal manifestations. Therefore, a field survey made possible to identify 101 mineral water discharges in the Azores, mainly of CO2-rich cold waters and thermal waters, spread along São Miguel (75%), Terceira (6%), Graciosa (7%), Pico (2%), Faial (3%), São Jorge (5%) and Flores ( 2%) islands, as well as fumarolic grounds. Furnas and Fogo central volcanoes, two of the three composite active volcanoes that dominates the geology of São Miguel, the largest island of the archipelago, represent respectively about 41% and 24% of the discharges from the Azores. Discharges are mainly from fissured aquifers, made of basaltic or trachitic lava flows. Instead, discharges from porous aquifers, made of pyroclastic deposits, mainly of pumice type, are less common, and are more frequent at São Miguel island. The studied discharges correspond mainly to springs (75), and also to boiling pools (10), at fumarolic grounds, 14 drilled wells and 2 large-diameter wells. The boiling pools are only observable at São Miguel island, while drilled wells were made at São Miguel, Terceira and Graciosa. Groundwater at Azores occurs in two major aquifers systems: (1) the basal aquifer system, which corresponds to fresh-water lenses floating on underlying salt water, and (2) in perched-water bodies. The basal aquifer system is in the coastal area, presenting generally a very low hydraulic gradient. From the 14 drilled wells only two are in perched-water bodies. Considering mineral springs, the majority discharge from perched-water bodies (77%), while all the boiling pools also discharge in altitude, also from perched -water bodies. During the field survey an extensive campaign of sample collection was made in all islands, in order to characterize the chemical composition of these waters

  19. Unsaturated zone hydrology and cave drip discharge water response: Implications for speleothem paleoclimate record variability

    NASA Astrophysics Data System (ADS)

    Markowska, Monika; Baker, Andy; Treble, Pauline C.; Andersen, Martin S.; Hankin, Stuart; Jex, Catherine N.; Tadros, Carol V.; Roach, Regina

    2015-10-01

    High-frequency, spatially-dense discharge monitoring was conducted over fifteen months to characterise unsaturated zone flow at Harrie Wood Cave (HWC), in the Snowy Mountains, Yarrangobilly (SE Australia). The cave was formed in the Late Silurian Yarrangobilly Limestone, a fractured rock associated with very low primary porosity due to past diagenesis. Over our monitoring period we simultaneously measured rainfall, soil moisture saturation and drip discharge rate at fourteen sites to characterise infiltration-discharge relationships. All drip discharge sites exhibited non-Gaussian distributions, indicating long periods where low discharge predominates, punctuated by short infrequent periods of high discharge. However, there was significant variability in discharge between sites and consequently no spatial correlation in the cave. We investigated the depth-discharge relationship at HWC and found a moderate relationship between depth and drip discharge lag (response) times to soil moisture content, but only weak relationships between depth and mean and maximum discharge. This highlights that the karst architecture plays an important role in controlling drip discharge dynamics. Principal Component Analysis (PCA) and Agglomerative Hierarchal Clustering (AHC) were used to classify similar drip types, revealing five unique drip regimes. Two-phase flow and non-linear response to recharge behaviour were observed, suggesting secondary porosity is controlling unsaturated zone flow in mature limestone environments with low primary porosity. Using the data presented here, the first coupled conceptual and box hydrological flow model was developed. This study highlights the heterogeneous nature of hydrological flow in karst and the need to understand unsaturated zone hydrology at the individual drip discharge level, to inform speleothem studies for high-resolution paleoclimate reconstruction.

  20. Late quaternary history and uranium isotopic compositions of ground water discharge deposits, Crater Flat, Nevada

    SciTech Connect

    Paces, J.B.; Taylor, E.M.; Bush, C.

    1993-12-31

    Three carbonate-rich spring deposits are present near the southern end of Crater Flat, NV, approximately 18 km southwest of the potential high-level waste repository at Yucca Mountain. We have analyzed five samples of carbonate-rich material from two of the deposits for U and Th isotopic compositions. Resulting U-series disequilibrium ages indicate that springs were active at 18 {+-} 1, 30 {+-} 3, 45 {+-} 4 and >70 ka. These ages are consistent with a crude internal stratigraphy at one site. Identical ages for two samples at two separate sites suggest that springs were contemporaneous, at least in part, and were most likely part of the same hydrodynamic system. In addition, initial U isotopic compositions range from 2.8 to 3.8 and strongly suggest that ground water from the regional Tertiary-volcanic aquifer provided the source for these hydrogenic deposits. This interpretation, along with water level data from near-by wells suggest that the water table rose approximately 80 to 115 m above present levels during the late Quaternary and may have fluctuated repeatedly. Current data are insufficient to allow reconstruction of a detailed depositional history, however geochronological data are in a good agreement with other paleoclimatic proxy records preserved throughout the region. Since these deposits are down gradient from the potential repository site, the possibility of higher ground water levels in the future dramatically shortens both vertical and lateral ground water pathways and reduces travel times of transported radionuclides to potential discharge sites.

  1. Shock wave generated by high-energy electric spark discharge

    NASA Astrophysics Data System (ADS)

    Liu, Qingming; Zhang, Yunming

    2014-10-01

    Shock wave generated by electric spark discharge was studied experimentally and the shock wave energy was evaluated in this paper. A pressure measurement system was established to study the pressure field of the electric spark discharge process. A series of electric spark discharge experiments were carried out and the energy of the electric spark used in present study was in the range of 10 J, 100 J, and 1000 J, respectively. The shock wave energy released from the electric spark discharge process was calculated by using the overpressure values at different measurement points near the electric spark discharge center. The good consistency of shock wave energies calculated by pressure histories at different measuring points in the same electric spark discharge experiment illustrates the applicability of the weak shock wave theory in calculating the energy of shock wave induced by electric spark discharge process. The result showed that shock wave formed at the initial stage of electric spark discharge process, and the shock wave energy is only a little part of electric spark energy. From the analysis of the shock wave energy and electric spark energy, a good linear relationship between shock wave energy and electric spark energy was established, which make it possible to calculate shock wave energy by measuring characteristic parameters of electric spark discharge process instead of shock wave. So, the initiation energy of direct initiation of detonation can be determined easily by measuring the parameters of electric spark discharge process.

  2. Assessing hazards due to contaminant discharge in coastal waters

    NASA Astrophysics Data System (ADS)

    Churchill, J. H.

    1987-02-01

    Models of contaminant dispersion in the marine environment have mostly sought to determine the mean concentration field. At a location not far from a pollution source, concentration is intermittently high, depending on whether the site is immersed in the concentrated contaminant plume which emanates from the source. At such a locale the probability of immersion, denoted by visitation frequency, is a more meaningful measure of nuisance than mean concentration. Two methods of computing visitation frequency from moored current meter data, each having particular advantages and drawbacks, are presented. One technique estimates visitation frequency from probability distributions of the position and velocity of water parcels originating from the effluent source. The second method entails simulating the configuration and movement of a contaminant plume. Required by both schemes is the plume cross-axial width as a function of time since release. A simple procedure of approximating this using the results of dye diffusion studies is described. These methods are applied to the coastal region off Long Island, New York, where current meter and dye diffusion data are available.

  3. Prediction of diffuse sulfate emissions from a former mining district and associated groundwater discharges to surface waters

    NASA Astrophysics Data System (ADS)

    Graupner, Bastian J.; Koch, Christian; Prommer, Henning

    2014-05-01

    Rivers draining mining districts are often affected by the diffuse input of polluted groundwaters. The severity and longevity of the impact depends on a wide range of factors such as the source terms, the hydraulic regime, the distance between pollutant sources and discharge points and the dilution by discharge from upstream river reaches. In this study a deterministic multi-mine life-cycle model was developed. It is used to characterize pollutant sources and to quantify the resulting current and future effects on both groundwater and river water quality. Thereby sulfate acts as proxy for mining-related impacts. The model application to the Lausitz mining district (Germany) shows that the most important factors controlling concentrations and discharge of sulfate are mixing/dilution with ambient groundwater and the rates of biological sulfate reduction during subsurface transport. In contrast, future impacts originating from the unsaturated zones of the mining dumps showed to be of little importance due to the high age of the mining dumps and the associated depletion in reactive iron-sulfides. The simulations indicate that currently the groundwater borne diffuse input of sulfate into the rivers Kleine Spree and Spree is ∼2200 t/years. Our predictions suggest a future increase to ∼11,000 t/years within the next 40 years. Depending on river discharge rates this represents an increase in sulfate concentration of 40-300 mg/L. A trend reversal for the surface water discharge is not expected before 2050.

  4. Estimated ground-water discharge by evapotranspiration, Ash Meadows Area, Nye County, Nevada, 1994

    SciTech Connect

    Nichols, W.D.; Laczniak, R.J.; DeMeo, G.A.; Rapp, T.R.

    1997-05-01

    Ground water discharges from the regional ground-water flow system that underlies the eastern part of the Nevada Test Site through numerous springs and seeps in the Ash Meadows National Wildlife Refuge in southern Nevada. The total spring discharge was estimated to be about 17,000 acre-feet per year by earlier studies. Previous studies estimated that about 10,500 acre-feet of this discharge was lost to evapotranspiration. The present study was undertaken to develop a more rigorous approach to estimating ground-water discharge in the Ash Meadows area. Part of the study involves detailed field investigation of evapotranspiration. Data collection began in early 1994. The results of the first year of study provide a basis for making preliminary estimates of ground-water discharge by evapotranspiration. An estimated 13,100 acre-feet of ground water was evapotranspired from about 6,800 acres of marsh and salt-grass. Additional 3,500 acre-feet may have been transpired from the open water and from about 1,460 acres of other areas of Ash Meadows in which field studies have not yet been made.

  5. High-pressure dc glow discharges in hollow diamond cathodes

    NASA Astrophysics Data System (ADS)

    Truscott, B. S.; Turner, C.; May, P. W.

    2016-04-01

    We report the generation and characterization of dc helium microdischarges at several times atmospheric pressure in monolithic diamond hollow-cathode devices having cavity diameters on the order of 100 μm. I-V characteristics indicated operation in the glow discharge regime even at nearly 10 atm, while spectroscopic measurements of the N2 C3Πu  →  B3Πg emission returned rotational temperatures always around 420 K, with a pressure-dependent vibrational population distribution. The variation of breakdown voltage with pressure closely followed Paschen’s law, but with offsets in both axes that we tentatively ascribe to strong diffusive loss and a partial thermalization of electron energies under the high pressures considered here.

  6. A modified resistance equation for modeling underwater spark discharge with salinity and high pressure conditions

    SciTech Connect

    Zhao, Pengfei; Roy, Subrata

    2014-05-07

    This work investigates the performance of underwater spark discharge relating to bubble growth and decay under high pressure and with salinity conditions by introducing a modified form of the resistance equation. Here, we study salinity influence on circuit parameters by fitting the experimental data for which gap resistance is much larger in conductive water than in dielectric water. Accordingly, the resistance equation is modified by considering the influence of both plasma and its surrounding liquid. Thermal radiation effect of the bubble is also studied by comparing two different radiation models. Numerical results predict a larger bubble pressure for saline water but a reduced size and a smaller bubble cycle at a greater water depth. Such study may be useful in many saltwater applications, including that for deep sea conditions.

  7. Effects of air transient spark discharge and helium plasma jet on water, bacteria, cells, and biomolecules.

    PubMed

    Hensel, Karol; Kučerová, Katarína; Tarabová, Barbora; Janda, Mário; Machala, Zdenko; Sano, Kaori; Mihai, Cosmin Teodor; Ciorpac, Mitică; Gorgan, Lucian Dragos; Jijie, Roxana; Pohoata, Valentin; Topala, Ionut

    2015-01-01

    Atmospheric pressure DC-driven self-pulsing transient spark (TS) discharge operated in air and pulse-driven dielectric barrier discharge plasma jet (PJ) operated in helium in contact with water solutions were used for inducing chemical effects in water solutions, and the treatment of bacteria (Escherichia coli), mammalian cells (Vero line normal cells, HeLa line cancerous cells), deoxyribonucleic acid (dsDNA), and protein (bovine serum albumin). Two different methods of water solution supply were used in the TS: water electrode system and water spray system. The effects of both TS systems and the PJ were compared, as well as a direct exposure of the solution to the discharge with an indirect exposure to the discharge activated gas flow. The chemical analysis of water solutions was performed by using colorimetric methods of UV-VIS absorption spectrophotometry. The bactericidal effects of the discharges on bacteria were evaluated by standard microbiological plate count method. Viability, apoptosis and cell cycle were assessed in normal and cancerous cells. Viability of cells was evaluated by trypan blue exclusion test, apoptosis by Annexin V-FITC/propidium iodide assay, and cell cycle progression by propidium iodide/RNase test. The effect of the discharges on deoxyribonucleic acid and protein were evaluated by fluorescence and UV absorption spectroscopy. The results of bacterial and mammalian cell viability, apoptosis, and cell cycle clearly show that cold plasma can inactivate bacteria and selectively target cancerous cells, which is very important for possible future development of new plasma therapeutic strategies in biomedicine. The authors found that all investigated bio-effects were stronger with the air TS discharge than with the He PJ, even in indirect exposure. PMID:25947389

  8. EFFECTS OF THERMAL DISCHARGES ON PHYSICO-CHEMICAL PROCESSES AND WATER QUALITY, VISTULA RIVER, POLAND

    EPA Science Inventory

    A study on the influence of thermal water discharge from the Koezienice power plant on thermal regimes and water quality of the Vistula River was carried out between January 1973 and December 1975. Results of field survey of the thermal plume indicate that under non-extreme condi...

  9. 33 CFR 151.2040 - Discharge of ballast water in extraordinary circumstances.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... requirements of 33 CFR 151.1515. (b) If the installed BWMS required by this subpart stops operating properly... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Discharge of ballast water in... OF HOMELAND SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES,...

  10. 33 CFR 151.2040 - Discharge of ballast water in extraordinary circumstances.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... requirements of 33 CFR 151.1515. (b) If the installed BWMS required by this subpart stops operating properly... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Discharge of ballast water in... OF HOMELAND SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES,...

  11. 33 CFR 151.2040 - Discharge of ballast water in extraordinary circumstances.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... requirements of 33 CFR 151.1515. (b) If the installed BWMS required by this subpart stops operating properly... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Discharge of ballast water in... OF HOMELAND SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES,...

  12. Application of Microsecond Voltage Pulses for Water Disinfection by Diaphragm Electric Discharge

    NASA Astrophysics Data System (ADS)

    Kakaurov, S. V.; Suvorov, I. F.; Yudin, A. S.; Solovyova, T. L.; Kuznetsova, N. S.

    2015-11-01

    The paper presents the dependence of copper and silver ions formation on the duration of voltage pulses of diaphragm electric discharge and on the pH of treated liquid medium. Knowing it allows one to create an automatic control system to control bactericidal agent's parameters obtained in diaphragm electric discharge reactor. The current-voltage characteristic of the reactor with a horizontal to the diaphragm membrane water flow powered from the author's custom pulse voltage source is also presented. The results of studies of the power consumption of diaphragm electric discharge depending on temperature of the treated liquid medium are given.

  13. Plutonium discharges to the sanitary sewer: Health impacts at the Livermore Water Reclamation Plant

    SciTech Connect

    Balke, B.K.

    1993-04-16

    The Lawrence Livermore National Laboratory (LLNL) is the largest discharger of sewage treated by the Livermore Water Reclamation (LWRP), contributing approximately 7% by volume of the LWRP influent LILNL operations, as potential sources both of industrial pollutants and radioactivity, are therefore of particular concern to the LWRP. For this reason, LLNL has maintained vigorous wastewater discharge control and monitoring programs. In particular, the monitoring program has demonstrated that, except in a few rare instances, the concentration of contaminants in LLNL effluent have always remained below the appropriate regulatory standards. The exceptions have generally been due to inadvertent discharges of metals-bearing solutions produced by metal plating or cleaning operations.

  14. Gas-discharge probe microscopy of water-carrying channels in wood

    NASA Astrophysics Data System (ADS)

    Ivanov-Omskii, V. I.; Ivanova, E. I.

    2012-04-01

    We have used a gas-discharge imaging technique to study the water transport channels (tracheids) in wood samples. Results obtained for the samples of bitch and aspen show features of this variant of the probe microscopy and show its additional possibilities as compared to optical microscopy. It is concluded that gas-discharge probe microscopy can be used for additional diagnostics of the structure of plant and animal tissues.

  15. RF physics of ICWC discharge at high cyclotron harmonics

    SciTech Connect

    Lyssoivan, A.; Van Eester, D.; Wauters, T.; Vervier, M.; Van Schoor, M.; Bobkov, V.; Rohde, V.; Schneider, P.; Douai, D.; Kogut, D.; Kreter, A.; Möller, S.; Philipps, V.; Sergienko, G.; Moiseenko, V.; Noterdaeme, J.-M.; Collaboration: TEXTOR Team; ASDEX Upgrade Team

    2014-02-12

    Recent experiments on Ion Cyclotron Wall Conditioning (ICWC) performed in tokamaks TEXTOR and ASDEX Upgrade with standard ICRF antennas operated at fixed frequencies but variable toroidal magnetic field demonstrated rather contrasting parameters of ICWC discharge in scenarios with on-axis fundamental ion cyclotron resonance (ICR) for protons,ω=ω{sub H+}, and with its high cyclotron harmonics (HCH), ω=10ω{sub cH+}⋅ HCH scenario: very high antenna coupling to low density RF plasmas (P{sub pl}≈0.9P{sub RF-G}) and low energy Maxwellian distribution of CX hydrogen atoms with temperature T{sub H}≈350 eV. Fundamental ICR: lower antenna-plasma coupling efficiency (by factor of about 1.5 times) and generation of high energy non-Maxwellian CX hydrogen atoms (with local energy E{sub ⊥H} ≥1.0 keV). In the present paper, we analyze the obtained experimental results numerically using (i) newly developed 0-D transport code describing the process of plasma production with electron and ion collisional ionization in helium-hydrogen gas mixture and (ii) earlier developed 1-D Dispersion Relation Solver accounting for finite temperature effects and collision absorption mechanisms for all plasma species in addition to conventionally examined Landau/TTPM damping for electrons and cyclotron absorption for ions. The numerical study of plasma production in helium with minor hydrogen content in low and high toroidal magnetic fields is presented. The investigation of the excitation, conversion and absorption of plasma waves as function of B{sub T}-field suggests that only fast waves (FW) may give a crucial impact on antenna coupling and characteristics of the ICWC discharge using standard poloidally polarized ICRF antennas designed to couple RF power mainly to FW. The collisional (non-resonant) absorption by electrons and ions and IC absorption by resonant ions of minor concentration in low T{sub e} plasmas is studied at fundamental ICR and its high harmonics.

  16. 77 FR 33969 - Standards for Living Organisms in Ships' Ballast Water Discharged in U.S. Waters

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-08

    ... FR 17254), entitled ``Standards for Living Organisms in Ships' Ballast Water Discharged in U.S... March 23, 2012 (77 FR 17254), entitled ``Standards for Living Organisms in Ships' Ballast Water... Standards Directorate''. Notification should be provided to U.S. Coast Guard Marine Safety Center. In FR...

  17. 77 FR 17253 - Standards for Living Organisms in Ships' Ballast Water Discharged in U.S. Waters

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-23

    ... Environmental Impact Statement FR final rule GRT gross register tons GSI Great Ships Initiative GT gross tons... Water Discharged in U.S. Waters'' in the Federal Register (74 FR 44632). In response, we received 662... requiring Coast Guard approval. 44 FR 73038 (December 17, 1979). The Coast Guard promulgated 46 CFR part...

  18. The effects of precipitation, river discharge, land use and coastal circulation on water quality in coastal Maine

    PubMed Central

    Tilburg, Charles E.; Jordan, Linda M.; Carlson, Amy E.; Zeeman, Stephan I.; Yund, Philip O.

    2015-01-01

    Faecal pollution in stormwater, wastewater and direct run-off can carry zoonotic pathogens to streams, rivers and the ocean, reduce water quality, and affect both recreational and commercial fishing areas of the coastal ocean. Typically, the closure of beaches and commercial fishing areas is governed by the testing for the presence of faecal bacteria, which requires an 18–24 h period for sample incubation. As water quality can change during this testing period, the need for accurate and timely predictions of coastal water quality has become acute. In this study, we: (i) examine the relationship between water quality, precipitation and river discharge at several locations within the Gulf of Maine, and (ii) use multiple linear regression models based on readily obtainable hydrometeorological measurements to predict water quality events at five coastal locations. Analysis of a 12 year dataset revealed that high river discharge and/or precipitation events can lead to reduced water quality; however, the use of only these two parameters to predict water quality can result in a number of errors. Analysis of a higher frequency, 2 year study using multiple linear regression models revealed that precipitation, salinity, river discharge, winds, seasonality and coastal circulation correlate with variations in water quality. Although there has been extensive development of regression models for freshwater, this is one of the first attempts to create a mechanistic model to predict water quality in coastal marine waters. Model performance is similar to that of efforts in other regions, which have incorporated models into water resource managers' decisions, indicating that the use of a mechanistic model in coastal Maine is feasible. PMID:26587258

  19. The effects of precipitation, river discharge, land use and coastal circulation on water quality in coastal Maine.

    PubMed

    Tilburg, Charles E; Jordan, Linda M; Carlson, Amy E; Zeeman, Stephan I; Yund, Philip O

    2015-07-01

    Faecal pollution in stormwater, wastewater and direct run-off can carry zoonotic pathogens to streams, rivers and the ocean, reduce water quality, and affect both recreational and commercial fishing areas of the coastal ocean. Typically, the closure of beaches and commercial fishing areas is governed by the testing for the presence of faecal bacteria, which requires an 18-24 h period for sample incubation. As water quality can change during this testing period, the need for accurate and timely predictions of coastal water quality has become acute. In this study, we: (i) examine the relationship between water quality, precipitation and river discharge at several locations within the Gulf of Maine, and (ii) use multiple linear regression models based on readily obtainable hydrometeorological measurements to predict water quality events at five coastal locations. Analysis of a 12 year dataset revealed that high river discharge and/or precipitation events can lead to reduced water quality; however, the use of only these two parameters to predict water quality can result in a number of errors. Analysis of a higher frequency, 2 year study using multiple linear regression models revealed that precipitation, salinity, river discharge, winds, seasonality and coastal circulation correlate with variations in water quality. Although there has been extensive development of regression models for freshwater, this is one of the first attempts to create a mechanistic model to predict water quality in coastal marine waters. Model performance is similar to that of efforts in other regions, which have incorporated models into water resource managers' decisions, indicating that the use of a mechanistic model in coastal Maine is feasible. PMID:26587258

  20. Density matters: Approaches to settling ballast water discharge concentrations

    EPA Science Inventory

    A consensus has evolved that invasion risk increases with propagule pressure. However, translating this general principal into ecologically “acceptable” concentrations of organisms in ballast water has proven challenging. The treaty being promulgated by the International Maritime...

  1. Ballast water regulations and the move toward concentration-based numeric discharge limits.

    PubMed

    Albert, Ryan J; Lishman, John M; Saxena, Juhi R

    2013-03-01

    Ballast water from shipping is a principal source for the introduction of nonindigenous species. As a result, numerous government bodies have adopted various ballast water management practices and discharge standards to slow or eliminate the future introduction and dispersal of these nonindigenous species. For researchers studying ballast water issues, understanding the regulatory framework is helpful to define the scope of research needed by policy makers to develop effective regulations. However, for most scientists, this information is difficult to obtain because it is outside the standard scientific literature and often difficult to interpret. This paper provides a brief review of the regulatory framework directed toward scientists studying ballast water and aquatic invasive species issues. We describe different approaches to ballast water management in international, U.S. federal and state, and domestic ballast water regulation. Specifically, we discuss standards established by the International Maritime Organization (IMO), the U.S. Coast Guard and U.S. Environmental Protection Agency, and individual states in the United States including California, New York, and Minnesota. Additionally, outside the United States, countries such as Australia, Canada, and New Zealand have well-established domestic ballast water regulatory regimes. Different approaches to regulation have recently resulted in variations between numeric concentration-based ballast water discharge limits, particularly in the United States, as well as reliance on use of ballast water exchange pending development and adoption of rigorous science-based discharge standards. To date, numeric concentration-based discharge limits have not generally been based upon a thorough application of risk-assessment methodologies. Regulators, making decisions based on the available information and methodologies before them, have consequently established varying standards, or not established standards at all. The

  2. Effect of Oxygen Gas on the Decomposition of Dye by Pulsed Discharge in Water Droplet Spray

    NASA Astrophysics Data System (ADS)

    Nose, Taisuke; Yokoyama, Yuzo; Nakamura, Akira; Minamitani, Yasushi

    Effect of O2 on the decolorization of indigo carmine and on the production of dissolved species such as NO2-, NO3-, O3 and H2O2 in the treatment water by pulsed discharge in water droplet spray was investigated by controlling the O2/N2 ratios as carrier gases in the reactor. The decolorization rate gradually increased with rise in O2 ratio, which reached a constant value in the range of 50% to 90% O2 ratio and decreased in pure O2. The maximum value was about 2 times as high as that of 20% O2 ratio. The decolorization efficiency was not affected by gas flow rate in the range of 4 L/min to 50 L/min. NO2- in the treatment water was only detected in pure N2, but NO3- was produced in O2/N2. NO2- added to the treatment water was not oxidized in pure N2, but was perfectly converted to NO3- in O2/N2. These results implied that hydroxyl radical produced in gas phase does not directly contribute to the oxidation of substances in water. O3 concentration gradually increased with rise in O2 ratio, whereas H2O2 concentration decreased. In the range of 50 to 80% O2 ratio, O3 and H2O2 concentrations were approximately constant value, similar to the trend of decolorization rate. Moreover rate constants on various gas mixing ratio of O2/N2 were determined from the kinetics study. These results suggested that hydroxyl radical produced in the treatment water by the chain reactions of O3 and hydroperoxy radical (HO2·) plays an important role of the decomposition of molecules in water.

  3. Characteristics of produced water discharged to the Gulf of Mexico hypoxiczone.

    SciTech Connect

    Veil, J. A.; Kimmell, T. A.; Rechner, A. C.

    2005-08-24

    Each summer, an area of low dissolved oxygen (the hypoxic zone) forms in the shallow nearshore Gulf of Mexico waters from the Mississippi River Delta westward to near the Texas/Louisiana border. Most scientists believe that the leading contributor to the hypoxic zone is input of nutrients (primarily nitrogen and phosphorus compounds) from the Mississippi and Atchafalaya Rivers. The nutrients stimulate growth of phytoplankton. As the phytoplankton subsequently die, they fall to the bottom waters where they are decomposed by microorganisms. The decomposition process consumes oxygen in the bottom waters to create hypoxic conditions. Sources other than the two rivers mentioned above may also contribute significant quantities of oxygen-demanding pollutants. One very visible potential source is the hundreds of offshore oil and gas platforms located within or near the hypoxic zone. Many of these platforms discharge varying volumes of produced water. However, only limited data characterizing oxygen demand and nutrient concentration and loading from offshore produced water discharges have been collected. No comprehensive and coordinated oxygen demand data exist for produced water discharges in the Gulf of Mexico. This report describes the results of a program to sample 50 offshore oil and gas platforms located within the Gulf of Mexico hypoxic zone. The program was conducted in response to a requirement in the U.S. Environmental Protection Agency (EPA) general National Pollutant Discharge Elimination System (NPDES) permit for offshore oil and gas discharges. EPA requested information on the amount of oxygen-demanding substances contained in the produced water discharges. This information is needed as inputs to several water quality models that EPA intends to run to estimate the relative contributions of the produced water discharges to the occurrence of the hypoxic zone. Sixteen platforms were sampled 3 times each at approximately one-month intervals to give an estimate of

  4. In-stream Physical Heterogeneity, Rainfall Aided Flushing, and Discharge on Stream Water Quality.

    PubMed

    Gomes, Pattiyage I A; Wai, Onyx W H

    2015-08-01

    Implications of instream physical heterogeneity, rainfall-aided flushing, and stream discharge on water quality control have been investigated in a headwater stream of a climatic region that has contrasting dry and wet seasons. Dry (low flow) season's physical heterogeneity showed a positive correlation with good water quality. However, in the wet season, physical heterogeneity showed minor or no significance on water quality variations. Furthermore, physical heterogeneity appeared to be more complementary with good water quality subsequent to rainfall events. In many cases stream discharge was a reason for poor water quality. For the dry season, graywater inputs to the stream could be held responsible. In the wet season, it was probably the result of catchment level disturbances (e.g., regulation of ephemeral freshwater paths). Overall, this study revealed the importance of catchment-based approaches on water quality improvement in tandem with in-stream approaches framed on a temporal scale. PMID:26237692

  5. Hyporheic discharge of river water into fall chinook salmon (Oncorhynchus tshawytscha) spawning areas in the Hanford Reach, Columbia River

    SciTech Connect

    Geist, David R. )

    1999-12-01

    Fall chinook salmon (Oncorhynchus tshawytscha) spawned predominantly in areas of the Hanford Reach of the Columbia River where hyporheic water discharged into the river channel. This upwelling water had a dissolved solids content (i.e., specific conductance) indicative of river water and was presumed to have entered highly permeable riverbed substrate at locations upstream of the spawning areas. Hyporheic discharge zones composed of undiluted ground water or areas with little or no upwelling were not used by spawning salmon. Rates of upwelling into spawning areas averaged 1,200 L?m-2?day-1 (95% C.I.= 784 to 1,665 L?m-2?day-1) as compared to approximately 500 L?m-2?day-1 (95% C.I.= 303 to 1,159 L?m-2?day-1) in non-spawning areas. Dissolved oxygen content of the hyporheic discharge near salmon spawning areas was about 9 mg?L-1 (+ 0.4 mg?L-1) whereas in non-spawning areas dissolved oxygen values were 7 mg?L-1 (+ 0.9 mg?L-1) or lower. In both cases dissolved oxygen of the river water was higher (11.3+ 0.3 mg?L-1). Physical and chemical gradients between the hyporheic zone and the river may provide cues for adult salmon to locate suitable spawning areas. This information will help fisheries managers to describe the suitability of salmon spawning habitat in large rivers.

  6. Ground-penetrating radar methods used in surface-water discharge measurements

    USGS Publications Warehouse

    Haeni, F.P.; Buursink, Marc L.; Costa, John E.; Melcher, Nick B.; Cheng, Ralph T.; Plant, William J.

    2000-01-01

    In 1999, an experiment was conducted to see if a combination of complementary radar methods could be used to calculate the discharge of a river without having any of the measuring equipment in the water. The cross-sectional area of the 183-meter wide Skagit River in Washington State was measured using a ground-penetrating radar (GPR) system with a single 100-MHz antenna. A van-mounted, side-looking pulsed-Doppler radar system was used to collect water-surface velocity data across the same section of the river. The combined radar data sets were used to calculate the river discharge and the results compared closely to the discharge measurement made by using the standard in-water measurement techniques.

  7. Differential Inactivation of Fungal Spores in Water and on Seeds by Ozone and Arc Discharge Plasma.

    PubMed

    Kang, Min Ho; Pengkit, Anchalee; Choi, Kihong; Jeon, Seong Sil; Choi, Hyo Won; Shin, Dong Bum; Choi, Eun Ha; Uhm, Han Sup; Park, Gyungsoon

    2015-01-01

    Seed sterilization is essential for preventing seed borne fungal diseases. Sterilization tools based on physical technologies have recently received much attention. However, available information is very limited in terms of efficiency, safety, and mode of action. In this study, we have examined antifungal activity of ozone and arc discharge plasma, potential tools for seed sterilization. In our results, ozone and arc discharge plasma have shown differential antifungal effects, depending on the environment associated with fungal spores (freely submerged in water or infected seeds). Ozone inactivates Fusarium fujikuroi (fungus causing rice bakanae disease) spores submerged in water more efficiently than arc discharge plasma. However, fungal spores associated with or infecting rice seeds are more effectively deactivated by arc discharge plasma. ROS generated in water by ozone may function as a powerful fungicidal factor. On the other hand, shockwave generated from arc discharge plasma may have greatly contributed to antifungal effects on fungus associated with rice seeds. In support of this notion, addition of ultrasonic wave in ozone generating water has greatly increased the efficiency of seed disinfection. PMID:26406468

  8. Differential Inactivation of Fungal Spores in Water and on Seeds by Ozone and Arc Discharge Plasma

    PubMed Central

    Kang, Min Ho; Pengkit, Anchalee; Choi, Kihong; Jeon, Seong Sil; Choi, Hyo Won; Shin, Dong Bum; Choi, Eun Ha; Uhm, Han Sup; Park, Gyungsoon

    2015-01-01

    Seed sterilization is essential for preventing seed borne fungal diseases. Sterilization tools based on physical technologies have recently received much attention. However, available information is very limited in terms of efficiency, safety, and mode of action. In this study, we have examined antifungal activity of ozone and arc discharge plasma, potential tools for seed sterilization. In our results, ozone and arc discharge plasma have shown differential antifungal effects, depending on the environment associated with fungal spores (freely submerged in water or infected seeds). Ozone inactivates Fusarium fujikuroi (fungus causing rice bakanae disease) spores submerged in water more efficiently than arc discharge plasma. However, fungal spores associated with or infecting rice seeds are more effectively deactivated by arc discharge plasma. ROS generated in water by ozone may function as a powerful fungicidal factor. On the other hand, shockwave generated from arc discharge plasma may have greatly contributed to antifungal effects on fungus associated with rice seeds. In support of this notion, addition of ultrasonic wave in ozone generating water has greatly increased the efficiency of seed disinfection. PMID:26406468

  9. Dielectric surface discharges: Effects of combined low-energy and high-energy incident electrons

    NASA Technical Reports Server (NTRS)

    Balmain, K. G.; Hirt, W.

    1981-01-01

    Dielectric surface discharges affected by the addition of high energy electrons at 5 pA/sq cm to a primary 20 keV, 10 nA/sq cm electron beam with the high energy broad spectrum particles coming from the beta decay of Strontium 90 are studied. Kapton exhibits significantly increased discharge strength, increased waiting time between discharges, and a decreased number of discharges per specimen before discharge cessation. Mylar exhibits similar but less pronounced effects, while Teflon is relatively unaffected. With Kapton and Mylar, the high energy electrons act in some way to delay the instant of discharge ignition so that more charge can be accumulated and hence released during discharge.

  10. Dielectric surface discharges - Effects of combined low-energy and high-energy incident electrons

    NASA Technical Reports Server (NTRS)

    Balmain, K. G.; Hirt, W.

    1983-01-01

    Dielectric surface discharges affected by the addition of high energy electrons at 5 pA/sq cm to a primary 20 keV, 10 nA/sq cm electron beam with the high energy broad spectrum particles coming from the beta decay of Strontium 90 are studied. Kapton exhibits significantly increased discharge strength, increased waiting time between discharges, and a decreased number of discharges per specimen before discharge cessation. Mylar exhibits similar but less pronounced effects, while Teflon is relatively unaffected. With Kapton and Mylar, the high energy electrons act in some way to delay the instant of discharge ignition so that more charge can be accumulated and hence released during discharge. Previously announced in STAR as N82-14222