Partial Discharge Ultrasound Detection Using the Sagnac Interferometer System

PubMed Central

Li, Xiaomin; Gao, Yan; Zhang, Hongjuan; Wang, Dong; Jin, Baoquan

2018-01-01

Partial discharge detection is crucial for electrical cable safety evaluation. The ultrasonic signals frequently generated in the partial discharge process contains important characteristic information. However, traditional ultrasonic transducers are easily subject to strong electromagnetic interference in environments with high voltages and strong magnetic fields. In order to overcome this problem, an optical fiber Sagnac interferometer system is proposed for partial discharge ultrasound detection. Optical fiber sensing and time-frequency analysis of the ultrasonic signals excited by the piezoelectric ultrasonic transducer is realized for the first time. The effective frequency band of the Sagnac interferometer system was up to 175 kHz with the help of a designed 10 kV partial discharge simulator device. Using the cumulative histogram method, the characteristic ultrasonic frequency band of the partial discharges was between 28.9 kHz and 57.6 kHz for this optical fiber partial discharge detection system. This new ultrasound sensor can be used as an ideal ultrasonic source for the intrinsically safe detection of partial discharges in an explosive environment. PMID:29734682

Testing Ionizers for Nitrogen Discharge of Interferometer Optics

NASA Astrophysics Data System (ADS)

Amen, Timothy; Ugolini, Dennis

2010-10-01

Interferometric gravitational-wave observatories consist of suspended optics in a vacuum chamber. Charge can build up on and then discontinuously jump across an optic, creating a changing electric field, causing the optic to sway, creating a false signal. We studied possible ways to discharge an optic without damaging their reflective coatings. We tried two types of electron guns. The first was built at the University of Washington and uses an ultraviolet LED to free electrons from a magnesium target. We found the current to be three orders of magnitude less than necessary for discharge in a reasonable time. The second gun used was a Bayard-Alpert gauge. To eliminate sputtering caused by the gauge above 10-4 torr, we employed a differential pumping system. We were able to flow nitrogen gas through the main chamber at pressures between 10-2 and 10-3 torr while the gauge chamber was kept two orders of magnitude lower. We successfully discharged the optic. The discharge rate varied exponentially with charge level and operating current and nearly linearly with acceleration voltage, and peaked when the pressure was 8 x 10-3 torr in the main chamber.

Dual-frequency glow discharges in atmospheric helium

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

Huang, Xiaojiang; Guo, Ying; Magnetic Confinement Fusion Research Center, Ministry of Education of the People's Republic of China, Shanghai 201620

2015-10-15

In this paper, the dual-frequency (DF) glow discharges in atmospheric helium were experimented by electrical and optical measurements in terms of current voltage characteristics and optical emission intensity. It is shown that the waveforms of applied voltages or discharge currents are the results of low frequency (LF) waveforms added to high frequency (HF) waveforms. The HF mainly influences discharge currents, and the LF mainly influences applied voltages. The gas temperatures of DF discharges are mainly affected by HF power rather than LF power.

AC Glow Discharge Plasma in N2O

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

Yousif, F. B.; Martinez, H.; Robledo-Martinez, A.

2006-12-04

This paper considers the optical and electrical characterization of AC glow discharge plasma in the abnormal glow mode used for optical emission spectroscopy. The total discharge current and applied voltage are measured using conventional techniques. The electrical characteristics of the planer-cathode glow discharge confirmed that the plasma is operating at abnormal discharge mode characterized by the increases in the operating voltage as the current was raised under given pressure. Optical emission spectroscopy was used to determine the main emission lines of the glow discharge plasma of N2O at pressures between 0.5 and 4.0 Torr. It shows that the discharge emissionmore » range is mainly within 300-400 nm. The emission lines correspond to NO, O2, and O{sub 2}{sup +} are the dominant lines in the glow discharge plasma in the present study. Intensity of the emission lines show linear increase with the discharge current up to 0.4 A followed by saturation at higher currents. No emission lines were observed in this work corresponding to atomic oxygen or nitrogen.« less

System OptimizatIon of the Glow Discharge Optical Spectroscopy Technique Used for Impurity Profiling of ION Implanted Gallium Arsenide.

DTIC Science & Technology

1980-12-01

AFIT/GEO/EE/80D-1 I -’ SYSTEM OPTIMIZATION OF THE GLOW DISCHARGE OPTICAL SPECTROSCOPY TECHNIQUE USED FOR IMPURITY PROFILING OF ION IMPLANTED GALLIUM ...EE/80D-1 (\\) SYSTEM OPTIMIZATION OF THE GLOW DISCHARGE OPTICAL SPECTROSCOPY TECHNIQUE USED FOR IMPURITY PROFILING OF ION IMPLANTED GALLIUM ARSENIDE...semiconductors, specifically annealed and unan- nealed ion implanted gallium arsenide (GaAs). Methods to improve the sensitivity of the GDOS system have

Exploding conducting film laser pumping apparatus

DOEpatents

Ware, Kenneth D.; Jones, Claude R.

1986-01-01

Exploding conducting film laser optical pumping apparatus. The 342-nm molecular iodine and the 1.315-.mu.m atomic iodine lasers have been optically pumped by intense light from exploding-metal-film discharges. Brightness temperatures for the exploding-film discharges were approximately 25,000 K. Although lower output energies were achieved for such discharges when compared to exploding-wire techniques, the larger surface area and smaller inductance inherent in the exploding-film should lead to improved efficiency for optically-pumped gas lasers.

Multichannel Dynamic Fourier-Transform IR Spectrometer

NASA Astrophysics Data System (ADS)

Balashov, A. A.; Vaguine, V. A.; Golyak, Il. S.; Morozov, A. N.; Khorokhorin, A. I.

2017-09-01

A design of a multichannel continuous scan Fourier-transform IR spectrometer for simultaneous recording and analysis of the spectral characteristics of several objects is proposed. For implementing the design, a multi-probe fiber is used, constructed from several optical fibers connected into a single optical connector and attached at the output of the interferometer. The Fourier-transform spectrometer is used as a signal modulator. Each fiber is individually mated with an investigated sample and a dedicated radiation detector. For the developed system, the radiation intensity of the spectrometer is calculated from the condition of the minimum spectral resolution and parameters of the optical fibers. Using the proposed design, emission spectra of a gas-discharge neon lamp have been recorded using a single fiber 1 mm in diameter with a numerical aperture NA = 0.22.

Production of Ar and Xe metastables in rare gas mixtures in a dielectric barrier discharge

NASA Astrophysics Data System (ADS)

Mikheyev, Pavel A.; Han, Jiande; Clark, Amanda; Sanderson, Carl; Heaven, Michael C.

2017-12-01

Optically pumped all-rare-gas lasers (OPRGL) utilize metastable atoms of the heavier rare gases as lasing species. The required number density of metastables for efficient laser operation is 1012-1013 cm-3 in He buffer gas at pressures in the 400-1000 Torr range. Such metastable densities are easily produced in a nanosecond pulsed discharge, even at pressures larger than atmospheric, but problems appear when one is trying to achieve continuous production. The reason for low production efficiency in many types of continuous discharge at atmospheric pressure is the low value of the E/N parameter (<5-6 Td). In the present work, we have examined the possibility of using a dielectric barrier discharge (DBD) to provide near continuous, high densities of Ar and Xe metastables. Experiments were performed using a 20 kHz DBD in binary Ar and Xe mixtures with He, and in ternary Ar:Xe:He mixtures at pressures up to 1 atmosphere. Concentrations were measured by means of tunable diode laser absorption spectroscopy. Time-averaged [Ar(1s5)] and [Xe(1s5)] number densities on the order of 1012 cm-3 were readily achieved. The temporal behavior of [Xe(1s5)] throughout the DBD cycle was observed. The results demonstrate the feasibility of using DBDs for OPRGL development. Spectral scans over the absorption lines were also used to examine the pressure broadening coefficients for the 912.3 nm Ar line in He and the Xe 904.5 nm line in Ne and He.

Discharge Characteristics of Series Surface/Packed-Bed Discharge Reactor Diven by Bipolar Pulsed Power

NASA Astrophysics Data System (ADS)

Hu, Jian; Jiang, Nan; Li, Jie; Shang, Kefeng; Lu, Na; Wu, Yan; Mizuno, Akira

2016-03-01

The discharge characteristics of the series surface/packed-bed discharge (SSPBD) reactor driven by bipolar pulse power were systemically investigated in this study. In order to evaluate the advantages of the SSPBD reactor, it was compared with traditional surface discharge (SD) reactor and packed-bed discharge (PBD) reactor in terms of the discharge voltage, discharge current, and ozone formation. The SSPBD reactor exhibited a faster rising time and lower tail voltage than the SD and PBD reactors. The distribution of the active species generated in different discharge regions of the SSPBD reactor was analyzed by optical emission spectra and ozone analysis. It was found that the packed-bed discharge region (3.5 mg/L), rather than the surface discharge region (1.3 mg/L) in the SSPBD reactor played a more important role in ozone generation. The optical emission spectroscopy analysis indicated that more intense peaks of the active species (e.g. N2 and OI) in the optical emission spectra were observed in the packed-bed region. supported by National Natural Science Foundation of China (No. 51177007), the Joint Funds of National Natural Science Foundation of China (No. U1462105), and Dalian University of Technology Fundamental Research Fund of China (No. DUT15RC(3)030)

Ion optics for high power 50-cm-diam ion thrusters

NASA Technical Reports Server (NTRS)

Rawlin, Vincent K.; Millis, Marc G.

1989-01-01

The process used at the NASA-Lewis to fabricate 30 and 50-cm-diameter ion optics is described. The ion extraction capabilities of the 30 and 50-cm diameter ion optics were evaluated on divergent field and ring-cusp discharge chambers and compared. Perveance was found to be sensitive to the effects of the type and power of the discharge chamber and to the accelerator electrode hole diameter. Levels of up to 0.64 N and 20 kW for thrust and input power, respectively, were demonstrated with the divergent-field discharge chamber. Thruster efficiencies and specific impulse values up to 79 percent and 5000 sec., respectively, were achieved with the ring-cusp discharge chamber.

Multicolor Photometric Observation of Lightning from Space: Comparison with Radio Measurements

NASA Technical Reports Server (NTRS)

Adachi, Toru; Cohen, Morris; Said, Ryan; Blakeslee, Richard J.; Cummer, Steven A.; Li, Jingbo; Lu, Geopeng; Hsu, Rue-Ron; Su, Han-Tzong; Chen, Alfred Bing-Chih;

Prediction of TARANIS Observations of TGF's and Optical Emissions from Red Sprites

NASA Astrophysics Data System (ADS)

Nelson, M. A.

2006-12-01

TARANIS (Tool for the Analysis of Radiation from Lightning and Sprites) is a French (CNES, Centre National D'Etudes Spatiales) micro-satellite that is scheduled for launch in 2009. This will be the first satellite that will measure coincident gamma-rays and optical emissions from atmospheric discharges. These measurements will provide important clues concerning the physics of discharges that produce gamma-rays and will provide more definitive evidence of the role of conventional breakdown versus runaway breakdown than is currently available. While a variety of discharges may be associated with Transient Gamma Ray Flashes (TGF's), this study will focus on emissions expected from red sprites. Future studies will focus on other types of discharges (for example, gigantic jets or blue jets) to see whether they should produce detectable signal levels at both gamma-ray and optical frequencies. The source of terrestrial TGF's is a matter of debate at this time. Many experts in the field have interpreted the data associated with the RHESSI (Reuven Ramaty High Energy Solar Spectroscopic Imager) satellite to be indicative that the discharges associated with terrestrial gamma-rays are not associated with sprites. However, RHESSI was not designed for the purpose of collecting gamma-ray measurements from terrestrial discharges; does not possess a coincident optical measurement capability; and must average data over many events to predict a spectrum. We will present a statistical analysis of the relative efficiencies of the RHESSI and TARANIS satellite designs for the detection of TGF's associated with sprites. We will show results from a fully 2-D electromagnetic model (UNIMAX, the Unified Maxwell code) and an optical model (POEM, the Physics Based Optical Emission Model) to demonstrate the level of agreement between the simulations and the gamma-ray spectrum measurements and optical measurements (camera, photometer, and spectral measurements) for several different classes of discharges (halos, streamers, and runaway breakdown.) We will distinguish which measurements and model results are indicative of conventional breakdown and which are indicative of runaway breakdown.

Electron density and temperature in an atmospheric-pressure helium diffuse dielectric barrier discharge from kHz to MHz

NASA Astrophysics Data System (ADS)

Boisvert, J.-S.; Stafford, L.; Naudé, N.; Margot, J.; Massines, F.

2018-03-01

Diffuse dielectric barrier discharges are generated over a very wide range of frequencies. According to the targeted frequency, the glow, Townsend-like, hybrid, Ω and RF-α modes are sustained. In this paper, the electrical characterization of the discharge cell together with an electrical model are used to estimate the electron density from current and voltage measurements for excitation frequencies ranging from 50 kHz to 15 MHz. The electron density is found to vary from 1014 to 1017 m-3 over this frequency range. In addition, a collisional-radiative model coupled with optical emission spectroscopy is used to evaluate the electron temperature (assuming Maxwellian electron energy distribution function) in the same conditions. The time and space-averaged electron temperature is found to be about 0.3 eV in both the low-frequency and high-frequency ranges. However, in the medium-frequency range, it reaches almost twice this value as the discharge is in the hybrid mode. The hybrid mode is similar to the atmospheric-pressure glow discharge usually observed in helium DBDs at low frequency with the major difference being that the plasma is continuously sustained and is characterized by a higher power density.

Mathematical model of optical signals emitted by electrical discharges occuring in electroinsulating oil

NASA Astrophysics Data System (ADS)

Kozioł, Michał

2017-10-01

The article presents a parametric model describing the registered distributions spectrum of optical radiation emitted by electrical discharges generated in the systems: the needle- needle, the needleplate and in the system for surface discharges. Generation of electrical discharges and registration of the emitted radiation was carried out in three different electrical insulating oils: fabric new, operated (used) and operated with air bubbles. For registration of optical spectra in the range of ultraviolet, visible and near infrared a high resolution spectrophotometer was. The proposed mathematical model was developed in a regression procedure using gauss-sigmoid type function. The dependent variable was the intensity of the recorded optical signals. In order to estimate the optimal parameters of the model an evolutionary algorithm was used. The optimization procedure was performed in Matlab environment. For determination of the matching quality of theoretical parameters of the regression function to the empirical data determination coefficient R2 was applied.

Ultrasonic Coating and Holographic Exposure Technology. Phase 1

DTIC Science & Technology

2015-09-01

introducing plaques to cure, which allowed the UV lamps to warm up. Temperature inside the UV oven could reach 35 °C if left on continuously. Curing time for...the deposition of thin films using an ultrasonic spray coater and patterning of the films using an ultraviolet ( UV ) laser. The main objectives for...required, and include such items as a corona discharge device, a UV curing oven, hot plate, and jigging for optics that were fabricated at Revision. Test

Multi-dimensional optical and laser-based diagnostics of low-temperature ionized plasma discharges

DOE PAGES

Barnat, Edward V.

2011-09-15

In this paper, a review of work centered on the utilization of multi-dimensional optical diagnostics to study phenomena arising in radiofrequency plasma discharges is given. The diagnostics range from passive techniques such as optical emission to more active techniques utilizing nanosecond lasers capable of both high temporal and spatial resolution. In this review, emphasis is placed on observations that would have been more difficult, if not impossible, to make without the use of such diagnostic techniques. Examples include the sheath structure around an electrode consisting of two different metals, double layers that arise in magnetized hydrogen discharges, or a largemore » region of depleted argon 1s 4 levels around a biased probe in an rf discharge.« less

The aquatic real-time monitoring network; in-situ optical sensors for monitoring the nation's water quality

USGS Publications Warehouse

Pellerin, Brian A.; Bergamaschi, Brian A.; Murdoch, Peter S.; Downing, Bryan D.; Saraceno, John Franco; Aiken, George R.; Striegl, Robert G.

2011-01-01

Floods, hurricanes, and longer-term changes in climate and land use can have profound effects on water quality due to shifts in hydrologic flow paths, water residence time, precipitation patterns, connectivity between rivers and uplands, and many other factors. In order to understand and respond to changes in hydrology and water quality, resource managers and policy makers have a need for accurate and early indicators, as well as the ability to assess possible mechanisms and likely outcomes. In-situ optical sensors-those making continuous measurements of constituents by absorbance or fluorescence properties in the environment at timescales of minutes to years-have a long history in oceanography for developing highly resolved concentrations and fluxes, but are not commonly used in freshwater systems. The United States Geological Survey (USGS) has developed the Aquatic Real-Time Monitoring Network, with high-resolution optical data collection for organic carbon, nutrients, and sediment in large coastal rivers, along with continuous measurements of discharge, water temperature, and dissolved inorganic carbon. The collecting of continuous water-quality data in the Nation?s waterways has revealed temporal trends and spatial patterns in constituents that traditional sampling approaches fail to capture, and will serve a critical role in monitoring, assessment and decision-making in a rapidly changing landscape.

Self-stabilized discharge filament in plane-parallel barrier discharge configuration: formation, breakdown mechanism, and memory effects

NASA Astrophysics Data System (ADS)

Tschiersch, R.; Nemschokmichal, S.; Bogaczyk, M.; Meichsner, J.

2017-10-01

Single self-stabilized discharge filaments were investigated in the plane-parallel electrode configuration. The barrier discharge was operated inside a gap of 3 mm shielded by glass plates to both electrodes, using helium-nitrogen mixtures and a square-wave feeding voltage at a frequency of 2 kHz. The combined application of electrical measurements, ICCD camera imaging, optical emission spectroscopy and surface charge diagnostics via the electro-optic Pockels effect allowed the correlation of the discharge development in the volume and on the dielectric surfaces. The formation criteria and existence regimes were found by systematic variation of the nitrogen admixture to helium, the total pressure and the feeding voltage amplitude. Single self-stabilized discharge filaments can be operated over a wide parameter range, foremost, by significant reduction of the voltage amplitude after the operation in the microdischarge regime. Here, the outstanding importance of the surface charge memory effect on the long-term stability was pointed out by the recalculated spatio-temporally resolved gap voltage. The optical emission revealed discharge characteristics that are partially reminiscent of both the glow-like barrier discharge and the microdischarge regime, such as a Townsend pre-phase, a fast cathode-directed ionization front during the breakdown and radially propagating surface discharges during the afterglow.

Corona discharge radical emission spectroscopy: a multi-channel detector with nose-type function for discrimination analysis.

PubMed

Tian, Yunfei; Wu, Peng; Wu, Xi; Jiang, Xiaoming; Xu, Kailai; Hou, Xiandeng

2013-04-21

A simple and economical multi-channel optical sensor using corona discharge radical emission spectroscopy is developed and explored as an optical nose for discrimination analysis of volatile organic compounds, wines, and even isomers.

Characteristics of the optical radiation from Kaufman thrusters

NASA Technical Reports Server (NTRS)

Milder, N. L.; Sovey, J. S.

1971-01-01

The optical radiation from plasma discharges of electron-bombardment mercury-ion thrusters was investigated. Spectrographic measurements indicated that the discharge was composed primarily of mercury atoms and singly charged ions. Excitation spectra of doubly charged mercury ions was measured to obtain the fraction of such ions in the discharge. Accomplishments of spectroscopic measurements of a hollow cathode thruster included the identification of two diagnostic lines in the mercury spectrum and the interpretation of the spectral amplitudes in terms of a superposition of primary and Maxwellian electron distributions. Potential application of optical techniques to thruster control applications was also suggested by the measurements.

Surface flow observations from a gauge-cam station on the Tiber river

NASA Astrophysics Data System (ADS)

Tauro, Flavia; Porfiri, Maurizio; Petroselli, Andrea; Grimaldi, Salvatore

2016-04-01

Understanding the kinematic organization of natural water bodies is central to hydrology and environmental engineering practice. Reliable and continuous flow observations are essential to comprehend flood generation and propagation mechanisms, erosion dynamics, sediment transport, and drainage network evolution. In engineering practice, flood warning systems largely rely on real-time discharge measurements, and flow velocity monitoring is important for the design and management of hydraulic structures, such as reservoirs and hydropower plants. Traditionally, gauging stations have been equipped with water level meters, and stage-discharge relationships (rating curves) have been established through few direct discharge measurements. Only in rare instances, monitoring stations have integrated radar technology for local measurement of surface flow velocity. Establishing accurate rating curves depends on the availability of a comprehensive range of discharge values, including measurements recorded during extreme events. However, discharge values during high-flow events are often difficult or even impossible to obtain, thereby hampering the reliability of discharge predictions. Fully remote observations have been enabled in the past ten years through optics-based velocimetry techniques. Such methodologies enable the estimation of the surface flow velocity field over extended regions from the motion of naturally occurring debris or floaters dragged by the current. Resting on the potential demonstrated by such approaches, here, we present a novel permanent gauge-cam station for the observation of the flow velocity field in the Tiber river. This new station captures one-minute videos every 10 minutes over an area of up to 20.6 × 15.5m2. In a feasibility study, we demonstrate that experimental images analyzed via particle tracking velocimetry and particle image velocimetry can be used to obtain accurate surface flow velocity estimations in close agreement with radar records. Future efforts will be devoted to the development of a comprehensive testbed infrastructure for investigating the potential of multiple optics-based approaches for surface hydrology.

LASER APPLICATIONS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Gas-dynamic effects in the interaction of a motionless optical pulsating discharge with gas

NASA Astrophysics Data System (ADS)

Tishchenko, V. N.; Grachev, G. N.; Pavlov, A. A.; Smirnov, A. L.; Pavlov, A. A.; Golubev, M. P.

2008-01-01

The effect of energy removal from the combustion zone of a motionless optical pulsating discharge in the horizontal direction along the axis of a repetitively pulsed laser beam producing the discharge is discovered. The directivity diagram of a hot gas flow is formed during the action of hundreds of pulses. The effect is observed for short pulse durations, when the discharge efficiently generates shock waves. For long pulse durations, the heated gas propagates upward, as in a thermal source.

LASER APPLICATIONS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Stationary force produced by an optical pulsating discharge in a laser engine model

NASA Astrophysics Data System (ADS)

Grachev, Gennadii N.; Tishchenko, V. N.; Apollonov, V. V.; Gulidov, A. I.; Smirnov, A. L.; Sobolev, A. V.; Zimin, M. I.

2007-07-01

An optical pulsating discharge produced by repetitively pulses laser radiation (with a pulse repetition rate of up to 100 kHz) is studied in a cylindrical tube simulating the reflector of a laser engine. The pressure of shock waves and the propulsion produced by them are measured. The discharge produced the stationary propulsion ~1 N kW-1.

Optical Diagnostic Characterization of High-Power Hall Thruster Wear and Operation

NASA Technical Reports Server (NTRS)

Williams, George J., Jr.; Soulas, George C.; Kamhawi, Hani

2012-01-01

Optical emission spectroscopy is employed to correlate BN insulator erosion with high-power Hall thruster operation. Specifically, actinometry leveraging excited xenon states is used to normalize the emission spectra of ground state boron as a function of thruster operating condition. Trends in the strength of the boron signal are correlated with thruster power, discharge voltage, and discharge current. In addition, the technique is demonstrated on metallic coupons embedded in the walls of the HiVHAc EM thruster. The OES technique captured the overall trend in the erosion of the coupons which boosts credibility in the method since there are no data to which to calibrate the erosion rates of high-power Hall thrusters. The boron signals are shown to trend linearly with discharge voltage for a fixed discharge current as expected. However, the boron signals of the higher-power NASA 300M and NASA 457Mv2 trend with discharge current and show an unexpectedly weak to inverse dependence on discharge voltage. Electron temperatures measured optically in the near-field plume of the thruster agree well with Langmuir probe data. However, the optical technique used to determine Te showed unacceptable sensitivity to the emission intensities. Near-field, single-frequency imaging of the xenon neutrals is also presented as a function of operating condition for the NASA 457 Mv2.

Titan's organic chemistry: Results of simulation experiments

NASA Technical Reports Server (NTRS)

Sagan, Carl; Thompson, W. Reid; Khare, Bishun N.

1992-01-01

Recent low pressure continuous low plasma discharge simulations of the auroral electron driven organic chemistry in Titan's mesosphere are reviewed. These simulations yielded results in good accord with Voyager observations of gas phase organic species. Optical constants of the brownish solid tholins produced in similar experiments are in good accord with Voyager observations of the Titan haze. Titan tholins are rich in prebiotic organic constituents; the Huygens entry probe may shed light on some of the processes that led to the origin of life on Earth.

Effect of pulsed discharge on the ignition of pulse modulated radio frequency glow discharge at atmospheric pressure

NASA Astrophysics Data System (ADS)

Qiu, Shenjie; Guo, Ying; Han, Qianhan; Bao, Yun; Zhang, Jing; Shi, J. J.

2018-01-01

A pulsed discharge is introduced between two sequential pulse-modulated radio frequency glow discharges in atmospheric helium. The dependence of radio frequency discharge ignition on pulsed discharge intensity is investigated experimentally with the pulse voltage amplitudes of 650, 850, and 1250 V. The discharge characteristics and dynamics are studied in terms of voltage and current waveforms, and spatial-temporal evolution of optical emission. With the elevated pulsed discharge intensity of two orders of magnitude, the ignition of radio frequency discharge is enhanced by reducing the ignition time and achieving the stable operation with a double-hump spatial profile. The ignition time of radio frequency discharge is estimated to be 2.0 μs, 1.5 μs, and 1.0 μs with the pulse voltage amplitudes of 650, 850, and 1250 V, respectively, which is also demonstrated by the spatial-temporal evolution of optical emission at 706 and 777 nm.

Exploding conducting film laser pumping apparatus

DOEpatents

Ware, K.D.; Jones, C.R.

1984-04-27

The 342-nm molecular iodine and the 1.315-..mu..m atomic iodine lasers have been optically pumped by intense light from exploding-metal-film discharges. Brightness temperatures for the exploding-film discharges were approximately 25,000 K. Although lower output energies were achieved for such discharges when compared to exploding-wire techniques, the larger surface area and smaller inductance inherent in the exploding-film should lead to improved efficiency for optically-pumped gas lasers.

Fifteen cm mercury ion thruster research, 1976. [performance as effected by the use of shag optics at 33 v discharge voltage

NASA Technical Reports Server (NTRS)

Wilbur, P. J.

1976-01-01

Improvements in 15 cm diameter, SERT II, mercury ion thruster performance effected by the use of SHAG optics at 33 V discharge voltage were discussed. At a 200 eV/ion discharge power, 90 percent propellant utilization and 660 mA beam current condition a doubly-to-singly charged ion current ratio of about 4 percent was measured. Performance of the 15 cm multipole mercury thruster (optimized for length and the point of electron injection) was compared to that of divergent (SERT II) and cusped field designs and found to be comparable. The need for a magnetic baffle in the multipole thruster was identified and the preferred point of electron injection was at the upstream end of the discharge chamber. Results of preliminary tests on the effects of discharge voltage and total accelerating voltage on perveance and beam divergence characteristics of two grid ion optics were examined. Experimental data showing the effect of target temperature on sputtering rates in a mercury discharge environment were presented and a deficiency in the tests procedure was identified.

Fluorescence excited in a thunderstorm atmosphere by relativistic runaway electron avalanches

NASA Astrophysics Data System (ADS)

Babich, L. P.; Bochkov, E. I.

2017-05-01

The spectrum and spatiotemporal evolution of the fluorescence of an atmospheric discharge developing in the regime of relativistic runaway electron avalanche (RREA) generation have been calculated without involving the relativistic feedback. The discharges generating narrow bipolar pulses, along with the discharges responsible for terrestrial gamma-ray flashes, are shown to be relatively dark. Nevertheless, the fluorescence excited by a discharge involving RREAs can be recorded with cameras used to record high-altitude optical phenomena. A possible connection between a certain class of optical phenomena observed at the tops of thunderclouds and RREA emission is pointed out.

Diamondoid synthesis in atmospheric pressure adamantane-argon-methane-hydrogen mixtures using a continuous flow plasma microreactor

NASA Astrophysics Data System (ADS)

Stauss, Sven; Ishii, Chikako; Pai, David Z.; Urabe, Keiichiro; Terashima, Kazuo

2014-06-01

Due to their small size, low-power consumption and potential for integration with other devices, microplasmas have been used increasingly for the synthesis of nanomaterials. Here, we have investigated the possibility of using dielectric barrier discharges generated in continuous flow glass microreactors for the synthesis of diamondoids, at temperatures of 300 and 320 K, and applied voltages of 3.2-4.3 kVp-p, at a frequency of 10 kHz. The microplasmas were generated in gas mixtures containing argon, methane, hydrogen and adamantane, which was used as a precursor and seed. The plasmas were monitored by optical emission spectroscopy measurements and the synthesized products were characterized by gas chromatography—mass spectrometry (GC-MS). Depending on the gas composition, the optical emission spectra contained CH and C2 bands of varying intensities. The GC-MS measurements revealed that diamantane can be synthesized by microplasmas generated at atmospheric pressure, and that the yields highly depend on the gas composition and the presence of carbon sources.

Studies of Low-Current Back-Discharge in Point-Plane Geometry with Dielectric Layer

NASA Astrophysics Data System (ADS)

Jaworek, Anatol; Rajch, Eryk; Krupa, Andrzej; Czech, Tadeusz; Lackowski, Marcin

2006-01-01

The paper presents results of spectroscopic investigations of back-discharges generated in the point-plane electrode geometry in ambient air at atmospheric pressure, with the plane electrode covered with a dielectric layer. Fly ash from an electrostatic precipitator of a coal-fired power plant was used as the dielectric layer in these investigations. The discharges for positive and negative polarities of the needle electrode were studied by measuring optical emission spectra at two regions of the discharge: near the needle electrode and dielectric layer surface. The visual forms of the discharge were recorded and correlated with the current-voltage characteristics and optical emission spectra. The back-arc discharge was of particular interest in these studies due to its detrimental effects it causes in electrostatic precipitators.

Eight electrode optical readout gap

DOEpatents

Boettcher, G.E.; Crain, R.W.

1984-01-01

A protective device for a plurality of electrical circuits includes a plurality of isolated electrodes forming a gap with a common electrode. An output signal, electrically isolated from the circuits being monitored, is obtained by a photosensor viewing the discharge gap through an optical window. Radioactive stabilization of discharge characteristics is provided for slowly changing voltages and carbon tipped dynamic starters provide desirable discharge characteristics for rapidly varying voltages. A hydrogen permeation barrier is provided on external surfaces of the device.

46 CFR 14.305 - Entries in continuous discharge book.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 1 2014-10-01 2014-10-01 false Entries in continuous discharge book. 14.305 Section 14.305 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT... discharge book. If the merchant mariner holds a continuous discharge book, the master or individual in...

46 CFR 14.305 - Entries in continuous discharge book.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 1 2012-10-01 2012-10-01 false Entries in continuous discharge book. 14.305 Section 14.305 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT... discharge book. If the merchant mariner holds a continuous discharge book, the master or individual in...

46 CFR 14.305 - Entries in continuous discharge book.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 1 2013-10-01 2013-10-01 false Entries in continuous discharge book. 14.305 Section 14.305 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT... discharge book. If the merchant mariner holds a continuous discharge book, the master or individual in...

46 CFR 14.305 - Entries in continuous discharge book.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 1 2011-10-01 2011-10-01 false Entries in continuous discharge book. 14.305 Section 14.305 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT... discharge book. If the merchant mariner holds a continuous discharge book, the master or individual in...

46 CFR 14.305 - Entries in continuous discharge book.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Entries in continuous discharge book. 14.305 Section 14.305 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT... discharge book. If the merchant mariner holds a continuous discharge book, the master or individual in...

Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

DTIC Science & Technology

2015-12-01

Wang, W. Zheng, and Y. N. Wang, "Optical study of radicals (OH, O, H, N) in a needle-plate negative pulsed streamer corona discharge ," Plasma...needle- plate bi-directional pulsed corona discharge ," European Physical Journal D, vol. 38, pp. 515-522, Jun 2006. 155 [35] W. Wang, S. Wang...F. Liu, W. Zheng, and D. Wang, "Optical study of OH radical in a wire-plate pulsed corona discharge ," Spectrochimica Acta Part A: Molecular and

Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

DTIC Science & Technology

2014-10-01

34Optical study of radicals (OH, O, H, N) in a needle- plate negative pulsed streamer corona discharge ," Plasma Chemistry and Plasma Processing, vol. 26...pulsed corona discharge ," European Physical Journal D, vol. 38, pp. 515-522, Jun 2006. [35] W. Wang, S. Wang, F. Liu, W. Zheng, and D. Wang, "Optical...study of OH radical in a wire-plate pulsed corona discharge ," Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, vol. 63, pp. 477

Discharge source with gas curtain for protecting optics from particles

DOEpatents

Fornaciari, Neal R.; Kanouff, Michael P.

2004-03-30

A gas curtain device is employed to deflect debris that is generated by an extreme ultraviolet and soft x-ray radiation discharge source such as an electric discharge plasma source. The gas curtain device projects a stream of gas over the path of the radiation to deflect debris particles into a direction that is different from that of the path of the radiation. The gas curtain can be employed to prevent debris accumulation on the optics used in photolithography.

Optical Emission Characterization of High-Power Hall Thruster Wear

NASA Technical Reports Server (NTRS)

WIlliams, George J.; Kamhawi, Hani

2013-01-01

Optical emission spectroscopy is employed to correlate BN insulator erosion with high-power operation of the NASA 300M Hall-effect thruster. Actinometry leveraging excited xenon states is used to normalize the emission spectra of ground state boron as a function of thruster operating condition. Trends in the strength of the boron signal are correlated with thruster power, discharge voltage, discharge current and magnetic field strength. The boron signals are shown to trend with discharge current and show weak dependence on discharge voltage. The trends are consistent with data previously collected on the NASA 300M and NASA 457M thrusters but are different from conventional wisdom.

In Situ Observation of Modulated Light Emission of Fiber Fuse Synchronized with Void Train over Hetero-Core Splice Point

PubMed Central

Todoroki, Shin-ichi

2008-01-01

Background Fiber fuse is a process of optical fiber destruction under the action of laser radiation, found 20 years ago. Once initiated, opical discharge runs along the fiber core region to the light source and leaves periodic voids whose shape looks like a bullet pointing the direction of laser beam. The relation between damage pattern and propagation mode of optical discharge is still unclear even after the first in situ observation three years ago. Methodology/Principal Findings Fiber fuse propagation over hetero-core splice point (Corning SMF-28e and HI 1060) was observed in situ. Sequential photographs obtained at intervals of 2.78 µs recorded a periodic emission at the tail of an optical discharge pumped by 1070 nm and 9 W light. The signal stopped when the discharge ran over the splice point. The corresponding damage pattern left in the fiber core region included a segment free of periodicity. Conclusions The spatial modulation pattern of the light emission agreed with the void train formed over the hetero-core splice point. Some segments included a bullet-shaped void pointing in the opposite direction to the laser beam propagation although the sequential photographs did not reveal any directional change in the optical discharge propagation. PMID:18815621

Studies of EUV contamination mitigation

NASA Astrophysics Data System (ADS)

Graham, Samual, Jr.; Malinowski, Michael E.; Steinhaus, Chip; Grunow, Philip A.; Klebanoff, Leonard E.

2002-07-01

Carbon contamination removal was investigated using remote RF-O2, RF-H2, and atomic hydrogen experiments. Samples consisted of silicon wafers coated with 100 Angstrom sputtered carbon, as well as bare Si-capped Mo/Si optics. Samples were exposed to atomic hydrogen or RF plasma discharges at 100 W, 200 W, and 300 W. Carbon removal rate, optic oxidation rate, at-wavelength (13.4 nm) peak reflectance, and optic surface roughness were characterized. Data show that RF- O2 removes carbon at a rate approximately 6 times faster RF- H2 for a given discharge power. However, both cleaning techniques induce Mo/Si optic degradation through the loss of reflectivity associated with surface oxide growth for RF-O2 and an unknown mechanism with hydrogen cleaning. Atomic hydrogen cleaning shows carbon removal rates sufficient for use as an in-situ cleaning strategy for EUVoptics with less risk of optic degradation from overexposures than RF-discharge cleaning. While hydrogen cleaning (RF and atomic) of EUV optics has proven effective in carbon removal, attempts to dissociate hydrogen in co-exposures with EUV radiation have resulted in no detectable removal of carbon contamination.

A Fiber Optic PD Sensor Using a Balanced Sagnac Interferometer and an EDFA-Based DOP Tunable Fiber Ring Laser

PubMed Central

Wang, Lutang; Fang, Nian; Wu, Chunxu; Qin, Haijuan; Huang, Zhaoming

2014-01-01

A novel fiber-optic acoustic sensor using an erbium-doped fiber amplifier (EDFA)-based fiber ring laser and a balanced Sagnac interferometer for acoustic sensing of the partial discharge (PD) in power transformers is proposed and demonstrated. As a technical background, an experimental investigation on how the variations of the fiber birefringence affect the sensor performances was carried out, and the results are discussed. The operation principles are described, and the relevant formulas are derived. The analytical results show that an EDFA-based fiber ring laser operating in chaotic mode can provide a degree of polarization (DOP) tunable light beam for effectively suppressing polarization fading noises. The balanced Sagnac interferometer can eliminate command intensity noises and enhance the signal-to-noise ratio (SNR). Furthermore, it inherently operates at the quadrature point of the response curve without any active stabilizations. Several experiments are conducted for evaluating the performances of the sensor system, as well as for investigating the ability of the detection of high-frequency acoustic emission signals. The experimental results demonstrate that the DOP of the laser beam can be continuously tuned from 0.2% to 100%, and the power fluctuation in the whole DOP tuning range is less than 0.05 dBm. A high-frequency response up to 300 kHz is reached, and the high sensing sensitivity for detections of weak corona discharges, as well as partial discharges also is verified. PMID:24824371

A comparison between initial continuous currents of different types of upward lightning

NASA Astrophysics Data System (ADS)

Wang, D.; Sawada, N.; Takagi, N.

2009-12-01

We have observed the lightning to a wind turbine and its lightning-protection tower for four consecutive winter seasons from 2005 to 2009. Our observation items include (1) thunderstorm electrical fields and lightning-caused electric field changes at multi sites around the wind turbine, (2) electrical currents at the bottom of the wind turbine and its lightning protection tower, (3) normal video and high speed image of lightning optical channels. Totally, we have obtained the data for 42 lightning that hit either on wind turbine or its lightning protection tower or both. Among these 42 lightning, 38 are upward lightning and 2 are downward lightning. We found the upward lightning can be sub-classified into two types. Type 1 upward lightning are self-triggered from a high structure, while type 2 lightning are triggered by a discharge occurred in other places which could be either a cloud discharge or a cloud-to-ground discharge (other-triggered). In this study, we have compared the two types of upward lightning in terms of initial continuous current rise time, peak current and charge transferred to the ground. We found that the initial current of self-triggered lightning tends to rise significantly faster and to a bigger peak value than the other-triggered lightning, although both types of lightning transferred similar amount of charge to the ground.

Extending helium partial pressure measurement technology to JET DTE2 and ITER.

PubMed

Klepper, C C; Biewer, T M; Kruezi, U; Vartanian, S; Douai, D; Hillis, D L; Marcus, C

2016-11-01

The detection limit for helium (He) partial pressure monitoring via the Penning discharge optical emission diagnostic, mainly used for tokamak divertor effluent gas analysis, is shown here to be possible for He concentrations down to 0.1% in predominantly deuterium effluents. This result from a dedicated laboratory study means that the technique can now be extended to intrinsically (non-injected) He produced as fusion reaction ash in deuterium-tritium experiments. The paper also examines threshold ionization mass spectroscopy as a potential backup to the optical technique, but finds that further development is needed to attain with plasma pulse-relevant response times. Both these studies are presented in the context of continuing development of plasma pulse-resolving, residual gas analysis for the upcoming JET deuterium-tritium campaign (DTE2) and for ITER.

Electrodeless-discharge-vapor-lamp-based Faraday anomalous-dispersion optical filter.

PubMed

Sun, Qinqing; Zhuang, Wei; Liu, Zhiwen; Chen, Jingbiao

2011-12-01

We report an excited-state Faraday anomalous-dispersion optical filter operating on the rubidium 5P(3/2)-5D(5/2) transition (775.9 nm in vacuum) without the use of a pump laser. An electrodeless discharge vapor lamp is employed to replace the Rb vapor cell in a traditional Faraday anomalous-dispersion optical filter system. Atoms can be excited by power rather than a complex frequency-locked pump laser. A proof-of-concept experimental demonstration with a maximum transmission of 1.9% and a filter bandwidth of 650 MHz is presented. © 2011 Optical Society of America

Electrical and optical properties of Ar/NH{sub 3} atmospheric pressure plasma jet

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

Chang, Zheng-Shi, E-mail: changzhsh1984@163.com, E-mail: gjzhang@xjtu.edu.cn; Yao, Cong-Wei; Chen, Si-Le

Inspired by the Penning effect, we obtain a glow-like plasma jet by mixing ammonia (NH{sub 3}) into argon (Ar) gas under atmospheric pressure. The basic electrical and optical properties of an atmospheric pressure plasma jet (APPJ) are investigated. It can be seen that the discharge mode transforms from filamentary to glow-like when a little ammonia is added into the pure argon. The electrical and optical analyses contribute to the explanation of this phenomenon. The discharge mode, power, and current density are analyzed to understand the electrical behavior of the APPJ. Meanwhile, the discharge images, APPJ's length, and the components ofmore » plasma are also obtained to express its optical characteristics. Finally, we diagnose several parameters, such as gas temperature, electron temperature, and density, as well as the density number of metastable argon atoms of Ar/NH{sub 3} APPJ to help judge the usability in its applications.« less

Absolute Spatially- and Temporally-Resolved Optical Emission Measurements of rf Glow Discharges in Argon

PubMed Central

Djurović, S.; Roberts, J. R.; Sobolewski, M. A.; Olthoff, J. K.

1993-01-01

Spatially- and temporally-resolved measurements of optical emission intensities are presented from rf discharges in argon over a wide range of pressures (6.7 to 133 Pa) and applied rf voltages (75 to 200 V). Results of measurements of emission intensities are presented for both an atomic transition (Ar I, 750.4 nm) and an ionic transition (Ar II, 434.8 nm). The absolute scale of these optical emissions has been determined by comparison with the optical emission from a calibrated standard lamp. All measurements were made in a well-defined rf reactor. They provide detailed characterization of local time-resolved plasma conditions suitable for the comparison with results from other experiments and theoretical models. These measurements represent a new level of detail in diagnostic measurements of rf plasmas, and provide insight into the electron transport properties of rf discharges. PMID:28053464

Fiber Optic Sensor for Acoustic Detection of Partial Discharges in Oil-Paper Insulated Electrical Systems

PubMed Central

Posada-Roman, Julio; Garcia-Souto, Jose A.; Rubio-Serrano, Jesus

2012-01-01

A fiber optic interferometric sensor with an intrinsic transducer along a length of the fiber is presented for ultrasound measurements of the acoustic emission from partial discharges inside oil-filled power apparatus. The sensor is designed for high sensitivity measurements in a harsh electromagnetic field environment, with wide temperature changes and immersion in oil. It allows enough sensitivity for the application, for which the acoustic pressure is in the range of units of Pa at a frequency of 150 kHz. In addition, the accessibility to the sensing region is guaranteed by immune fiber-optic cables and the optical phase sensor output. The sensor design is a compact and rugged coil of fiber. In addition to a complete calibration, the in-situ results show that two types of partial discharges are measured through their acoustic emissions with the sensor immersed in oil. PMID:22666058

Observations of a mode transition in a hydrogen hollow cathode discharge using phase resolved optical emission spectroscopy

NASA Astrophysics Data System (ADS)

Dixon, Sam; Charles, Christine; Dedrick, James; Gans, Timo; O'Connell, Deborah; Boswell, Rod

2014-07-01

Two distinct operational modes are observed in a radio frequency (rf) low pressure hydrogen hollow cathode discharge. The mode transition is characterised by a change in total light emission and differing expansion structures. An intensified CCD camera is used to make phase resolved images of Balmer α emission from the discharge. The low emission mode is consistent with a typical γ discharge, and appears to be driven by secondary electrons ejected from the cathode surface. The bright mode displays characteristics common to an inductive discharge, including increased optical emission, power factor, and temperature of the H2 gas. The bright mode precipitates the formation of a stationary shock in the expansion, observed as a dark region adjacent to the source-chamber interface.

Sound spectrum of a pulsating optical discharge

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

Grachev, G N; Smirnov, A L; Tishchenko, V N

A spectrum of sound of an optical discharge generated by a repetitively pulsed (RP) laser radiation has been investigated. The parameters of laser radiation are determined at which the spectrum of sound may contains either many lines, or the main line at the pulse repetition rate and several weaker overtones, or a single line. The spectrum of sound produced by trains of RP radiation comprises the line (and overtones) at the repetition rate of train sequences and the line at the repetition rate of pulses in trains. A CO{sub 2} laser with the pulse repetition rate of f ≈ 3more » – 180 kHz and the average power of up to 2 W was used in the experiments. (optical discharges)« less

Initial Results Derived from JEM-GLIMS Observations

NASA Astrophysics Data System (ADS)

Sato, M.; Ushio, T.; Morimoto, T.; Kobayashi, N.; Takahashi, Y.; Suzuki, M.; Yamazaki, A.; Inan, U.; Linscott, I.; Hobara, Y.

2012-12-01

In order to identify the spatial distributions and occurrence conditions of TLEs, JEM-GLIMS (Global Lightning and sprIte MeasurementS on JEM-EF) observations from Japanese Experiment Module - Exposed Facility (JEM-EF) at International Space Station (ISS) will start this year. Science instruments of JEM-GLIMS consist of two kinds of optical detectors and two kinds of radio receivers. The optical instruments are two wide FOV CMOS cameras (LSI) and six-channel spectrophotometers (PH). LSI uses a CMOS device with 512x512 pixels as an imaging sensor and uses a CCTV lens with =25 mm/F=1.4 which becomes 28.3x28.3 deg. FOV. LSI-1 equips a wide band optical filter (766-832 nm) and mainly measures lightning emission, while LSI-2 equips a narrowband optical filter (762+/-7 nm) and mainly measures TLE emission. Five of six PH channels employ the optics with 42.7 deg. conical FOV and use photomultiplier tubes (PMTs) as photon detectors. Each channel of these photometers equips an optical band-pass filter to measure N2 1P, 2P, and LBH emissions. One of six photometers employs a wide-FOV optics (86.8 deg.) and wide-band filter to measure N2 1P lightning emission. All these optical instruments are pointed to the nadir direction. In order to detect whistler wave excited by lightning discharges, one VLF receiver (VLFR) is installed. VLFR consists of a 15 cm nadir-directing monopole antenna and an electronics unit recording waveform data with a sampling frequency of 100 kHz with 14-bit resolution. In addition to this, two sets of VHF receivers (VITF) are also installed to measure VHF pulses emitted by lightning discharges. VITF consists of two patch-type antennas separated by 1.5 m and an electronics unit which records pulse data with a sampling frequency of 200 MHz with 8-bit resolution. Thus, the spatial and temporal evolution of lightning and TLEs can be measured by the two optical instruments, while the electrical characteristics of sprite-inducing lightning discharges can be measured by two radio receivers. JEM-GIMS was successfully launched by H-IIB rocket at 02:06:18 UT on July 21, 2012 and transported to ISS by the HTV-3 cargo transfer spaceship. HTV-3 successfully arrived at ISS on July 27 and our JEM-GLIMS instruments will be installed at JEM-EF on August 9. For the period from September 15 to 21 we will carry out the initial checkout operation, and finally we will start continuous TLE observations from the middle of October. At the presentation we will show the test results obtained during the checkout operations and will present the initial results derived from JEM-GLIMS lightning/TLE observations.

Controlling the net charge on a nanoparticle optically levitated in vacuum

NASA Astrophysics Data System (ADS)

Frimmer, Martin; Luszcz, Karol; Ferreiro, Sandra; Jain, Vijay; Hebestreit, Erik; Novotny, Lukas

2017-06-01

Optically levitated nanoparticles in vacuum are a promising model system to test physics beyond our current understanding of quantum mechanics. Such experimental tests require extreme control over the dephasing of the levitated particle's motion. If the nanoparticle carries a finite net charge, it experiences a random Coulomb force due to fluctuating electric fields. This dephasing mechanism can be fully excluded by discharging the levitated particle. Here, we present a simple and reliable technique to control the charge on an optically levitated nanoparticle in vacuum. Our method is based on the generation of charges in an electric discharge and does not require additional optics or mechanics close to the optical trap.

Detrecting and Locating Partial Discharges in Transformers

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

Shourbaji, A.; Richards, R.; Kisner, R. A.

A collaborative research between the Oak Ridge National Laboratory (ORNL), the American Electric Power (AEP), the Tennessee Valley Authority (TVA), and the State of Ohio Energy Office (OEO) has been formed to conduct a feasibility study to detect and locate partial discharges (PDs) inside large transformers. The success of early detection of the PDs is necessary to avoid costly catastrophic failures that can occur if the process of PD is ignored. The detection method under this research is based on an innovative technology developed by ORNL researchers using optical methods to sense the acoustical energy produced by the PDs. ORNLmore » researchers conducted experimental studies to detect PD using an optical fiber as an acoustic sensor capable of detecting acoustical disturbances at any point along its length. This technical approach also has the potential to locate the point at which the PD was sensed within the transformer. Several optical approaches were experimentally investigated, including interferometric detection of acoustical disturbances along the sensing fiber, light detection and ranging (LIDAR) techniques using frequency modulation continuous wave (FMCW), frequency modulated (FM) laser with a multimode fiber, FM laser with a single mode fiber, and amplitude modulated (AM) laser with a multimode fiber. The implementation of the optical fiber-based acoustic measurement technique would include installing a fiber inside a transformer allowing real-time detection of PDs and determining their locations. The fibers are nonconductive and very small (core plus cladding are diameters of 125 μm for single-mode fibers and 230 μm for multimode fibers). The research identified the capabilities and limitations of using optical technology to detect and locate sources of acoustical disturbances such as in PDs in large transformers. Amplitude modulation techniques showed the most promising results and deserve further research to better quantify the technique’s sensitivity and its ability to characterize a PD event. Other sensing techniques have been also identified, such as the wavelength shifting fiber optics and custom fabricated fibers with special coatings.« less

Water Resources Data, Florida, Water Year 2003, Volume 1A: Northeast Florida Surface Water

USGS Publications Warehouse

,

2004-01-01

Water resources data for the 2003 water year in Florida consist of continuous or daily discharge for 385 streams, periodic discharge for 13 streams, continuous or daily stage for 255 streams, periodic stage for 13 streams, peak stage and discharge for 36 streams; continuous or daily elevations for 13 lakes, periodic elevations for 46 lakes; continuous ground-water levels for 441 wells, periodic ground-water levels for 1,227 wells; quality-of-water data for 133 surface-water sites and 308 wells. The data for northeast Florida include continuous or daily discharge for 138 streams, periodic discharge for 3 streams, continuous or daily stage for 61 streams, periodic stage for 0 streams; peak stage and discharge for 0 streams; continuous or daily elevations for 9 lakes, periodic elevations for 20 lakes; continuous ground water levels for 73 wells, periodic groundwater levels for 543 wells; quality-of-water data for 43 surface-water sites and 115 wells. These data represent the National Water Data System records collected by the U.S. Geological Survey and cooperating local, State and Federal agencies in Florida.

Water Resources Data, Florida, Water Year 2003, Volume 1B: Northeast Florida Ground Water

USGS Publications Warehouse

George, H.G.; Nazarian, A.P.; Dickerson, S.M.

2004-01-01

Water resources data for the 2003 water year in Florida consist of continuous or daily discharge for 385 streams, periodic discharge for 13 streams, continuous or daily stage for 255 streams, periodic stage for 13 streams, peak stage and discharge for 36 streams; continuous or daily elevations for 13 lakes, periodic elevations for 46 lakes; continuous ground-water levels for 441 wells, periodic ground-water levels for 1,227 wells; quality-of-water data for 133 surface-water sites and 308 wells. The data for northeast Florida include continuous or daily discharge for 138 streams, periodic discharge for 3 streams, continuous or daily stage for 61 streams, periodic stage for 0 streams; peak stage and discharge for 0 streams; continuous or daily elevations for 9 lakes, periodic elevations for 20 lakes; continuous ground water levels for 73 wells, periodic groundwater levels for 543 wells; quality-of-water data for 43 surface-water sites and 115 wells. These data represent the National Water Data System records collected by the U.S. Geological Survey and cooperating local, State and Federal agencies in Florida.

High effective heterogeneous plasma vortex reactor for production of heat energy and hydrogen

NASA Astrophysics Data System (ADS)

Belov, N. K.; Zavershinskii, I. P.; Klimov, A. I.; Molevich, N. E.; Porfiriev, D. P.; Tolkunov, B. N.

2018-03-01

This work is a continuation of our previous studies [1-10] of physical parameters and properties of a long-lived heterogeneous plasmoid (plasma formation with erosive nanoclusters) created by combined discharge in a high-speed swirl flow. Here interaction of metal nanoclusters with hydrogen atoms is studied in a plasma vortex reactor (PVR) with argon-water steam mixture. Metal nanoclusters were created by nickel cathode’s erosion at combined discharge on. Dissociated hydrogen atoms and ions were obtained in water steam by electric discharge. These hydrogen atoms and ions interacted with metal nanoclusters, which resulted in the creation of a stable plasmoid in a swirl gas flow. This plasmoid has been found to create intensive soft X-ray radiation. Plasma parameters of this plasmoid were measured by optical spectroscopy method. It has been obtained that there is a high non-equilibrium plasmoid: Te > TV >> TR. The measured coefficient of energy performance of this plasmoid is about COP = 2÷10. This extra power release in plasmoid is supposed to be connected with internal excited electrons. The obtained experimental results have proved our suggestion.

40 CFR 263.31 - Discharge clean up.

Code of Federal Regulations, 2010 CFR

2010-07-01

... hazardous waste discharge no longer presents a hazard to human health or the environment. ....31 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS APPLICABLE TO TRANSPORTERS OF HAZARDOUS WASTE Hazardous Waste Discharges § 263.31 Discharge clean...

40 CFR 263.31 - Discharge clean up.

Code of Federal Regulations, 2014 CFR

2014-07-01

... hazardous waste discharge no longer presents a hazard to human health or the environment. ....31 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS APPLICABLE TO TRANSPORTERS OF HAZARDOUS WASTE Hazardous Waste Discharges § 263.31 Discharge clean...

40 CFR 263.31 - Discharge clean up.

Code of Federal Regulations, 2013 CFR

2013-07-01

... hazardous waste discharge no longer presents a hazard to human health or the environment. ....31 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS APPLICABLE TO TRANSPORTERS OF HAZARDOUS WASTE Hazardous Waste Discharges § 263.31 Discharge clean...

40 CFR 263.31 - Discharge clean up.

Code of Federal Regulations, 2011 CFR

2011-07-01

... hazardous waste discharge no longer presents a hazard to human health or the environment. ....31 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS APPLICABLE TO TRANSPORTERS OF HAZARDOUS WASTE Hazardous Waste Discharges § 263.31 Discharge clean...

40 CFR 263.31 - Discharge clean up.

Code of Federal Regulations, 2012 CFR

2012-07-01

... hazardous waste discharge no longer presents a hazard to human health or the environment. ....31 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS APPLICABLE TO TRANSPORTERS OF HAZARDOUS WASTE Hazardous Waste Discharges § 263.31 Discharge clean...

Diagnostics of reactive oxygen species produced by microplasmas

NASA Astrophysics Data System (ADS)

Sousa, J. S.; Puech, V.

2013-11-01

Atmospheric pressure generation of reactive oxygen species (ROS) by microplasmas was experimentally studied. The remarkable stability of the microcathode sustained discharge (MCSD) allowed the operation of dc glow discharges, free from the glow-to-arc transition, in He/O2/NO mixtures at atmospheric pressure. Absolute densities of the main ROS were measured by different optical diagnostics: singlet delta oxygen (O2(a 1Δg)) by infrared emission and vacuum ultraviolet absorption in the effluent, ozone (O3) by ultraviolet absorption in the effluent, and atomic oxygen inside the discharge by two-photon absorption laser induced fluorescence. The effect of different parameters, such as gas flow and mixture, and discharge current, on the production of these ROS was studied. High ROS densities up to 1016 cm-3 were achieved. It is shown that the density ratio of O2(a 1Δg) to O3 can be finely tuned in the range [10-3-10+4], through the values of discharge current and NO concentration, and that high O2(a 1Δg) and O3 densities can be transported over distances longer than 50 cm. The MCSD is, thus, a very suitable tool for the continuous production at atmospheric pressure of large fluxes of O2(a 1Δg) and O3, useful to a wide range of applications, notably in plasma medicine.

Water Resources Data, Florida, Water Year 2003, Volume 3A: Southwest Florida Surface Water

USGS Publications Warehouse

Kane, R.L.; Fletcher, W.L.

2004-01-01

Water resources data for the 2003 water year in Florida consist of continuous or daily discharges for 385 streams, periodic discharge for 13 streams, continuous daily stage for 255 streams, periodic stage for 13 streams, peak stage for 36 streams and peak discharge for 36 streams, continuous or daily elevations for 13 lakes, periodic elevations for 46 lakes; continuous ground-water levels for 441 wells, periodic ground-water levels for 1,227 wells, and quality-of-water data for 133 surface-water sites and 308 wells. The data for Southwest Florida include records of stage, discharge, and water quality of streams; stage, contents, water quality of lakes and reservoirs, and water levels and water quality of ground-water wells. Volume 3A contains continuous or daily discharge for 103 streams, periodic discharge for 7 streams, continuous or daily stage for 67 streams, periodic stage for 13 streams, peak stage and discharge for 8 streams, continuous or daily elevations for 2 lakes, periodic elevations for 26 lakes, and quality-of-water data for 62 surface-water sites. These data represent the national Water Data System records collected by the U.S. Geological Survey and cooperating local, state, and federal agencies in Florida.

Experimental study on detection of electrostatic discharges generated by polymer granules inside a metal silo

NASA Astrophysics Data System (ADS)

Choi, Kwangseok; Mogami, Tomofumi; Suzuki, Teruo

2014-04-01

To detect electrostatic discharges generated by polymer granules within a metal silo, we developed a novel and simple electrostatic discharge detector that utilizes a photosensor. The novel detector consists of a photosensor module in a metal cylinder, an optical band-pass filter, a quartz glass, a power supply, an amplifier for the photosensor module, and a digital oscilloscope. In this study, we conducted experiments at a real pneumatic powder transport facility that includes a metal silo to evaluate the novel detector using polypropylene granules. To determine the performance of the novel detector, we observed the electrostatic discharge within the metal silo using a conventional image intensifier system. The results obtained from the experiments show that the novel detector worked well in this study. The signals obtained with the novel detector were identical to the electrostatic discharges obtained with the conventional image intensifier system. The greatest advantage of this novel detector is that it is effective even when placed under external lights. In addition, the influence of various optical band-pass filters on the performance of the novel detector was discussed. Our study confirmed that an optical band-pass filter with a center wavelength of λ 330 nm (λ1/2: 315-345 nm) was the best performer among the optical band-pass filters used in this study.

Experimental study on detection of electrostatic discharges generated by polymer granules inside a metal silo.

PubMed

Choi, Kwangseok; Mogami, Tomofumi; Suzuki, Teruo

2014-04-01

To detect electrostatic discharges generated by polymer granules within a metal silo, we developed a novel and simple electrostatic discharge detector that utilizes a photosensor. The novel detector consists of a photosensor module in a metal cylinder, an optical band-pass filter, a quartz glass, a power supply, an amplifier for the photosensor module, and a digital oscilloscope. In this study, we conducted experiments at a real pneumatic powder transport facility that includes a metal silo to evaluate the novel detector using polypropylene granules. To determine the performance of the novel detector, we observed the electrostatic discharge within the metal silo using a conventional image intensifier system. The results obtained from the experiments show that the novel detector worked well in this study. The signals obtained with the novel detector were identical to the electrostatic discharges obtained with the conventional image intensifier system. The greatest advantage of this novel detector is that it is effective even when placed under external lights. In addition, the influence of various optical band-pass filters on the performance of the novel detector was discussed. Our study confirmed that an optical band-pass filter with a center wavelength of λ 330 nm (λ1/2: 315-345 nm) was the best performer among the optical band-pass filters used in this study.

Charge Management in LISA Pathfinder: The Continuous Discharging Experiment

NASA Astrophysics Data System (ADS)

Ewing, Becca Elizabeth

2018-01-01

Test mass charging is a significant source of excess force and force noise in LISA Pathfinder (LPF). The planned design scheme for mitigation of charge induced force noise in LISA is a continuous discharge by UV light illumination. We report on analysis of a charge management experiment on-board LPF conducted during December 2016. We discuss the measurement of test mass charging noise with and without continuous UV illumination, in addition to the dynamic response in the continuous discharge scheme. Results of the continuous discharge system will be discussed for their application to operating LISA with lower test mass charge.

In situ dc oxygen‐discharge cleaning system for optical elements

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

Koide, Tsuneharu; Shidara, Tetsuo; Tanaka, Kenichiro

1989-07-15

In situ dc oxygen‐discharge cleaning arrangements have been developed at the Photon Factory for the removal of carbon contamination from optical surfaces. A high cleaning rate could be achieved by producing an oxygen plasma close to the optical elements with special care taken to avoid any harmful effects from the discharge; contaminant carbon was completely removed within a few hours, at most. This short exposure time and the use of dry oxygen gas resulted in a restoration of the original ultrahigh vacuum without a bakeout. Results with a Seya‐Namioka beamline for gas‐phase experiments showed a flux enhancement amounting to amore » factor of 50, and results with a grasshopper beamline showed a nearly complete recovery of the light intensity, even at the carbon K edge.« less

A sealed optical cell for the study of lithium-electrode|electrolyte interfaces

NASA Astrophysics Data System (ADS)

Howlett, P. C.; MacFarlane, D. R.; Hollenkamp, A. F.

A sealed, symmetrical, lithium optical cell, which enables optical images of lithium surface deposits and in situ Raman spectra to be obtained simply and conveniently during charge-discharge cycling of lithium metal electrodes, has been designed and tested. A conventional aprotic liquid, 1 M lithium hexafluorophosphate in propylene carbonate, and an experimental ionic liquid, 20 mol% lithium bis(trifluoromethanesulfonyl)amide in 1-ethyl 3-methyl imidazolium bis(trifluoromethanesulfonyl)amide, are investigated as electrolyte solutions. Images obtained from the cell with the former electrolyte solution demonstrate the problems associated with cycling lithium metal electrodes. Images obtained with the latter electrolyte solution provide clear evidence that continued investigation of ionic liquids for use with lithium metal electrodes is warranted. Operation of the cell with the conventional electrolyte yields Raman spectra of good quality. The spectra display vibrational modes which arise from the electrolyte, as well as several additional modes which are associated with the deposits formed during cycling.

Water Resources Data, Florida, Water Year 2003 Volume 2A: South Florida Surface Water

USGS Publications Warehouse

Price, C.; Woolverton, J.; Overton, K.

2004-01-01

Water resources data for 2003 water year in Florida consists of continuous or daily discharge for 385 streams, periodic discharge for 13 streams, continuous or daily stage for 255 streams, periodic stage for 13 stream, peak discharge for 36 streams, and peak stage for 36 streams, continuous or daily elevations for 13 lakes, periodic elevations for 46 lakes, continuous ground-water levels for 441 wells, periodic ground-water levels for 1227 wells, quality of water data for 133 surface-water sites, and 308 wells. The data for South Florida included continuous or daily discharge for 72 streams, continuous or daily stage for 50 streams, no peak stage discharge for streams, 1 continuous elevation for lake, continuous ground-water levels for 237 wells, periodic ground-water levels for 248 wells, water quality for 25 surface-water sites, and 161 wells. These data represent the National Water Data System records collected by the U.S. Geological Survey and cooperation with local, state, and federal agencies in Florida.

Water Resources Data, Florida, Water Year 2003 Volume 2B: South Florida Ground Water

USGS Publications Warehouse

Prinos, S.; Irvin, R.; Byrne, M.

2004-01-01

Water resources data for 2003 water year in Florida consists of continuous or daily discharge for 385 streams, periodic discharge for 13 streams, continuous or daily stage for 255 streams, periodic stage for 13 stream, peak discharge for 36 streams, and peak stage for 36 streams, continuous or daily elevations for 13 lakes, periodic elevations for 46 lakes, continuous ground-water levels for 441 wells, periodic ground-water levels for 1227 wells, quality of water data for 133 surface-water sites, and 308 wells. The data for South Florida included continuous or daily discharge for 72 streams, continuous or daily stage for 50 streams, no peak stage discharge for streams, 1 continuous elevation for lake, continuous ground-water levels for 237 wells, periodic ground-water levels for 248 wells, water quality for 25 surface-water sites, and 161 wells. These data represent the National Water Data System records collected by the U.S. Geological Survey and cooperation with local, state, and federal agencies in Florida.

Localized Electron Trap Modification as a Result of Space Weather Exposure in Highly Disordered Insulating Materials

DTIC Science & Technology

2017-03-06

4 Pre-transit discharge region (phase II) ........................................................................... 5 Post...transit Discharge Region (phase III) ...................................................................... 5 2.2. Optical Signature...3 Figure 2 Schematic of a charge/ discharge curve of an electron irradiated insulating material. .. 4

Ion source design for industrial applications

NASA Technical Reports Server (NTRS)

Kaufman, H. R.; Robinson, R. S.

1981-01-01

The more frequently used design techniques for the components of broad-beam electron bombardment ion sources are discussed. The approach used emphasizes refractory metal cathodes and permanent-magnet multipole discharge chambers. Design procedures and sample calculations are given for the discharge chamber, ion optics, the cathodes, and the magnetic circuit. Hardware designs are included for the isolator, cathode supports, anode supports, pole-piece assembly, and ion-optics supports. A comparison is made between two-grid and three-grid optics. The designs presented are representative of current technology and are adaptable to a wide range of configurations.

Production of nitrogen oxides in air pulse-periodic discharge with apokamp

NASA Astrophysics Data System (ADS)

Panarin, Victor A.; Skakun, Victor S.; Sosnin, Eduard A.; Tarasenko, Victor F.

2018-05-01

The decomposition products of pulse-periodic discharge atmospheric pressure plasma in apokamp, diffuse and corona modes were determined by optical and chemical methods. It is shown that apokamp discharge formation starts at a critical value of dissipation power in a discharge channel. Simultaneously, due to the thermochemical reactions, plasma starts to efficiently produce nitrogen oxides.

Development of a novel fiber-optic sensor to measure radon in the deep ocean

NASA Astrophysics Data System (ADS)

Monteiro, Catarina; Guimarães, Diana; Jorge, Pedro; Barbosa, Susana

2017-04-01

The radon concentration in the deep ocean has gained increasing interest in the last decades. The underwater monitoring of this natural radioactive gas can give important information about submarine groundwater discharges, groundwater migration and contamination. Radon concentration has also been studied as a possible indicator of earthquake events which can have devastating consequences when the epicenter is located at the sea. In contrast with radon monitoring studies in caves, mines, and underground soil, there is an utter lack of information about radon in deep-sea. These measurements are particularly difficult to attain due to the challenges that marine-like environments post to electronic sensing devices and their maintenance over time. Gamma rays emitted by radon's progeny can be easily detected when interacting with a scintillator material. Recently, optical fiber doped with scintillating material has emerged has an alternative for gamma ray detection. The lightweight, low transmission loss, immunity to electromagnetic interference and the cost effectiveness makes optical fiber a compelling solution for radiation detection when compared to conventional sensors. In this work a compact all-fiber optical sensor is developed for continuous gamma ray detection in the deep sea. This sensor is composed by a scintillating optical fiber coupled to a polymeric optical fiber that allows the detection of low levels of radiation.

Radio frequency observations of lightning discharges by the forte satellite.

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

Shao, X.; Jacobson, A. R.; Light, T.

2002-01-01

FORTE-observed VHF signatures for different lightning discharges are presented. For in-cloud discharges, a pulse pair is typically recorded and is named a 'transionospheric pulse pair' (TIPP). Many intense TIPPs are coherent and polarized, whereas initial and dart leaders do not show a recognizable degree of polarization. TIPPs are optically weaker than cloud-to-ground (CG) strokes, and stronger VHF TIPPs are optically darker. About 10% of CG strokes, mostly over seawater, produce extremely narrow, powerful VHF pulses at the very beginning of the return strokes. These narrow pulses are found to form an upward beam pattern.

Implications of water supply for indigenous Americans during Holocene ardity phases on the Southern High Plains, USA

USGS Publications Warehouse

Wood, W.W.; Stokes, S.; Rich, J.

2002-01-01

Springs in the 40 to 50 large lake basins (>15 km2) on the southern portion of the Southern High Plains (SHP) were active during periods of aridity in the Holocene when there may have been human habitation of the area. Eolian erosion of the lake floors and lunette accretion occurred as groundwater levels declined in response to decreased groundwater recharge. The declining lake floor associated with eolian erosion allowed groundwater evaporative discharge to continue, thus maintaining a groundwater gradient toward the lake. This hydrologic condition was favorable for a relatively continuous spring discharge to the lake, independent of the elevation of the lake floor. To evaluate the postulated dynamic equilibrium critical to this conclusion, 17 optically stimulated ages were determined from a 17.7-m deep core of a lunette adjacent to Double Lakes, Texas (33??13???15???N, 101??54???08???W). The core yielded sediment accumulation dates of 11,500 ?? 1100, 6500 ?? 700, and 4900 ?? 500 yr B.P., corresponding broadly with periods of aridity known from other evidence. Based on analysis of this lunette, it is concluded that springs in Double Lakes basin probably existed throughout the Holocene with discharges similar to those observed historically. We assumed that similar dynamic equilibrium existed in the other large lake basins in the SHP and that these springs could have provided a continuous source of water for indigenous peoples during periods of prolonged aridity. The dynamic equilibrium that is proposed in this study is applicable not only to other arid and semiarid geographic areas with wind-erodible material but also over different geologic times. ?? 2002 University of Washington.

/ital In/ /ital situ/ dc oxygen-discharge cleaning system for optical elements

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

Koide, T.; Shidara, T.; Tanaka, K.

1989-07-01

/ital In/ /ital situ/ dc oxygen-discharge cleaning arrangements have been developed at the Photon Factory for the removal of carbon contamination from optical surfaces. A high cleaning rate could be achieved by producing an oxygen plasma close to the optical elements with special care taken to avoid any harmful effects from the discharge; contaminant carbon was completely removed within a few hours, at most. This short exposure time and the use of dry oxygen gas resulted in a restoration of the original ultrahigh vacuum without a bakeout. Results with a Seya-Namioka beamline for gas-phase experiments showed a flux enhancement amountingmore » to a factor of 50, and results with a grasshopper beamline showed a nearly complete recovery of the light intensity, even at the carbon /ital K/ edge.« less

Development of a real time monitor and multivariate method for long term diagnostics of atmospheric pressure dielectric barrier discharges: application to He, He/N2, and He/O2 discharges.

PubMed

O'Connor, N; Milosavljević, V; Daniels, S

2011-08-01

In this paper we present the development and application of a real time atmospheric pressure discharge monitoring diagnostic. The software based diagnostic is designed to extract latent electrical and optical information associated with the operation of an atmospheric pressure dielectric barrier discharge (APDBD) over long time scales. Given that little is known about long term temporal effects in such discharges, the diagnostic methodology is applied to the monitoring of an APDBD in helium and helium with both 0.1% nitrogen and 0.1% oxygen gas admixtures over periods of tens of minutes. Given the large datasets associated with the experiments, it is shown that this process is much expedited through the novel application of multivariate correlations between the electrical and optical parameters of the corresponding chemistries which, in turn, facilitates comparisons between each individual chemistry also. The results of these studies show that the electrical and optical parameters of the discharge in helium and upon the addition of gas admixtures evolve over time scales far longer than the gas residence time and have been compared to current modelling works. It is envisaged that the diagnostic together with the application of multivariate correlations will be applied to rapid system identification and prototyping in both experimental and industrial APDBD systems in the future.

Electrical and optical characteristics of atmospheric pressure plasma needle jet driven by neon trasformer

NASA Astrophysics Data System (ADS)

Elfa, Rizan Rizon; Ahmad, Mohd Khairul; Soon, Chin Fhong; Sahdan, Mohd Zainizan; Lias, Jais; Mamat, Mohamad Hafiz; Rusop, Mohamad; Nayan, Nafarizal

2017-09-01

The atmospheric pressure plasma needle jet driven by double sinusoidal waveform of neon transformer is reported in this paper. The commercial neon transformer produces about 5 kV of peak sinusoidal voltages and 35 kHz of frequency. Argon gas has been used as discharge gas for this system since the discharge was easily developed rather than using helium gas. In addition, argon gas is three times cheaper than helium gas. The electrical property of the argon discharge has been analyzed in details by measuring its voltage, current and power during the discharge process. Interestingly, it has been found that the total power on the inner needle electrode was slightly lower than that of outer electrode. This may be due to the polarization charges that occurred at inner needle electrode. Then, further investigation to understand the discharge properties was carried out using optical emission spectroscopy (OES) analysis. During OES measurements, two positions of plasma discharge are measured by aligning the quartz optical lens and spectrometer fiber. The OH emission intensity was found higher than that of N2 at the plasma orifice. However, OH emission intensity was lower at 1.5 cm distance from orifice which may be due to penning ionization effect. These results and understanding are essential for surface modification and biomedical applications of atmospheric pressure plasma needle jet.

Dielectric Barrier Discharges: Pulsed Breakdown, Electrical Characterization and Chemistry

DTIC Science & Technology

2013-06-01

DIELECTRIC BARRIER DISCHARGES : PULSED BREAKDOWN, ELECTRICAL CHARACTERIZATION AND CHEMISTRY  R. Brandenburg, H. Höft, T. Hoder, A. Pipa, R...for pulsed driven Dielectric Barrier Discharges (DBDs) in particular. Fast electrical, optical and spectroscopic methods enable the study of...2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Dielectric Barrier Discharges : Pulsed Breakdown, Electrical Characterization

Optically triggered fire set/detonator system

DOEpatents

Chase, Jay B.; Pincosy, Philip A.; Chato, Donna M.; Kirbie, Hugh; James, Glen F.

2007-03-20

The present invention is directed to a system having a plurality of capacitor discharge units (CDUs) that includes electrical bridge type detonators operatively coupled to respective explosives. A pulse charging circuit is adapted to provide a voltage for each respective capacitor in each CDU. Such capacitors are discharged through the electrical bridge type detonators upon receiving an optical signal to detonate respective operatively coupled explosives at substantially the same time.

Summary of Optical-Backscatter and Suspended-Sediment Data, Tomales Bay Watershed, California, Water Years 2004, 2005, and 2006

USGS Publications Warehouse

Curtis, Jennifer A.

2007-01-01

The U.S. Geological Survey, in cooperation with Point Reyes National Seashore, is studying suspended-sediment transport dynamics in the two primary tributaries to Tomales Bay, Lagunitas Creek and Walker Creek. Suspended-sediment samples and continuous optical backscatter (turbidity) data were collected at three locations during water years 2004?06 (October 1, 2003?September 30, 2006): at two sites in the Lagunitas Creek watershed and at one site in the Walker Creek watershed. Sediment samples were analyzed for suspended-sediment concentration, grain size, and turbidity. Data were used to estimate mean daily and annual seasonal suspended-sediment discharge, which were published in U.S. Geological Survey Annual Water-Data Reports. Data were utilized further in this report to develop field-based optical-backscatter calibration equations, which then were used to derive a continuous time series (15-minute interval) of suspended-sediment concentrations. Sensor fouling and aggradation of the channel bed occurred periodically throughout the project period, resulting in data loss. Although periods of data loss occurred, collection of optical sensor data improved our understanding of suspended-sediment dynamics in the Lagunitas Creek and Walker Creek watersheds by providing continuous time-series storm event data that were analyzed to determine durations of elevated sediment concentrations (periods of time when suspended-sediment concentration was greater than 100 mg/L). Data derived from this project contributed baseline suspended-sediment transport information that will be used to develop and implement sediment total maximum daily loads for Tomales Bay and its tributary watersheds, and provides supporting information for additional total maximum daily loads (pathogens, nutrients, and mercury) and restoration efforts for four federally listed aquatic species that are affected directly by sediment loading in the Tomales Bay watershed. In addition, this project provided an opportunity to evaluate the suitability of using optical data as a surrogate for more traditional labor-intensive methods of measuring suspended-sediment transport in steep coastal watersheds.

On the exploitation of optical and thermal band for river discharge estimation: synergy with radar altimetry

NASA Astrophysics Data System (ADS)

Tarpanelli, Angelica; Filippucci, Paolo; Brocca, Luca

2017-04-01

River discharge is recognized as a fundamental physical variable and it is included among the Essential Climate Variables by GCOS (Global Climate Observing System). Notwithstanding river discharge is one of the most measured components of the hydrological cycle, its monitoring is still an open issue. Collection, archiving and distribution of river discharge data globally is limited, and the currently operating network is inadequate in many parts of the Earth and is still declining. Remote sensing, especially satellite sensors, have great potential in offering new ways to monitor river discharge. Remote sensing guarantees regular, uniform and global measurements for long period thanks to the large number of satellites launched during the last twenty years. Because of its nature, river discharge cannot be measured directly and both satellite and traditional monitoring are referred to measurements of other hydraulic variables, e.g. water level, flow velocity, water extent and slope. In this study, we illustrate the potential of different satellite sensors for river discharge estimation. The recent advances in radar altimetry technology offered important information for water levels monitoring of rivers even if the spatio-temporal sampling is still a limitation. The multi-mission approach, i.e. interpolating different altimetry tracks, has potential to cope with the spatial and temporal resolution, but so far few studies were dedicated to deal with this issue. Alternatively, optical sensors, thanks to their frequent revisit time and large spatial coverage, could give a better support for the evaluation of river discharge variations. In this study, we focus on the optical (Near InfraRed) and thermal bands of different satellite sensors (MODIS, MERIS, AATSR, Landsat, Sentinel-2) and particularly, on the derived products such as reflectance, emissivity and land surface temperature. The performances are compared with respect to the well-known altimetry (Envisat/Ra-2, Jason-2/Poseidon-3 and Saral/Altika) for estimating the river discharge variation in Nigeria and Italy. For optical and thermal bands, results are more affected by the temporal resolution than the spatial resolution. Indeed, even if affected by cloud cover that limits the number of available images, thermal bands from MODIS (spatial resolution of 1 km) can be conveniently used for the estimation of the variation in the river discharge, whereas optical sensors as Landsat or Sentinel-2, characterized by 10 - 30 m of spatial resolution, fail in the estimation of extreme events, missing most of the peak values, because of the long revisit time ( 14-16 days). The best performances are obtained with the Near InfraRed bands from MODIS and MERIS that give similar results in river discharge estimation, even though with some underestimation of the flood peak values. Moreover, the multi-mission approach applied to radar altimetry data is found to be the most reliable tool to estimate river discharge in large rivers but its success is constrained both spatially (number of satellite tracks) and temporally (revisit time of the satellites). Therefore, it is expected that the multi-mission approach, merging also sensors of different characteristics (radar altimetry, and optical/thermal sensors), could improve the performances, if a consistent and comparable methodology is used for reducing the inter-satellite biases.

Exploration of Gas Discharges with GaAs, GaP and ZnSe Electrodes Under Atmospheric Pressure

NASA Astrophysics Data System (ADS)

Kurt, H. Hilal

2018-03-01

This work reports on the electrical and optical characterization of the atmospheric pressure glow discharge regimes for different semiconductor electrodes made of GaAs, GaP and ZnSe. The discharge cell is driven by DC feeding voltages at a wide pressure range of 0.66-120 kPa in argon and air media for different interelectrode gaps. The discharge phenomena including different stages of discharges such as glow and Townsend breakdown have been examined. In addition, the infrared sensitivities of the semiconducting materials are evaluated in the micro-discharge cell and discharge light emission measurements have been performed. The qualities of the semiconducting electrode samples can be determined by seeking the homogeneity of the discharge light emission for the optoelectronic device applications. Operation of optical devices under atmospheric pressures gives certain advantages for manufacturing of the devices including the material processing and surface treatment procedures. Besides, finite element analyses of the overall experimental system have been performed for the abovementioned semiconductors. The electron densities and potential patterns have been determined on the discharge cell plane between the electrodes. The findings have proven that the electron densities along the plasma cell depend on both the semiconductor type and plasma parameters.

An Optical Fiber Viscometer Based on Long-Period Fiber Grating Technology and Capillary Tube Mechanism

PubMed Central

Wang, Jian-Neng; Tang, Jaw-Luen

2010-01-01

This work addresses the development and assessment of a fiber optical viscometer using a simple and low-cost long-period fiber grating (LPFG) level sensor and a capillary tube mechanism. Previous studies of optical viscosity sensors were conducted by using different optical sensing methods. The proposed optical viscometer consists of an LPFG sensor, a temperature-controlled chamber, and a cone-shaped reservoir where gravitational force could cause fluid to flow through the capillary tube. We focused on the use of LPFGs as level sensors and the wavelength shifts were not used to quantify the viscosity values of asphalt binders. When the LPFG sensor was immersed in the constant volume (100 mL) AC-20 asphalt binder, a wavelength shift was observed and acquired using LabVIEW software and GPIB controller. The time spent between empty and 100 mL was calculated to determine the discharge time. We simultaneously measured the LPFG-induced discharge time and the transmission spectra both in hot air and AC-20 asphalt binder at five different temperatures, 60, 80, 100, 135, and 170 Celsius. An electromechanical rotational viscometer was also used to measure the viscosities, 0.15–213.80 Pa·s, of the same asphalt binder at the above five temperatures. A non-linear regression analysis was performed to convert LPFG-induced discharge time into viscosities. Comparative analysis shows that the LPFG-induced discharge time agreed well with the viscosities obtained from the rotational viscometer. PMID:22163519

Nighttime observations of thunderstorm electrical activity from a high altitude airplane

NASA Technical Reports Server (NTRS)

Brook, M.; Vonnegut, B.; Orville, R. E.; Vaughan, O. H., Jr.

1984-01-01

Nocturnal thunderstorms were observed from above and features of cloud structure and lightning which are not generally visible from the ground are discussed. Most, lightning activity seems to be associated with clouds with strong convective cauliflower tops. In both of the storms lightning channels were visible in the clear air above the cloud. It is shown that substances produced by thunderstorm electrical discharges can be introduced directly into the stratosphere. The cause and nature of the discharges above the cloud are not clear. They may be produced by accumulations of space charge in the clear air above the cloud. The discharges may arise solely because of the intense electric fields produced by charges within the cloud. In the latter case the ions introduced by these discharges will increase the electrical conductivity of the air above the cloud and increase the conduction current that flows from the cloud to the electrosphere. More quantitative data at higher resolution may show significant spectral differences between cloud to ground and intracloud strokes. It is shown that electric field change data taken with an electric field change meter mounted in an airplane provide data on lightning discharges from above that are quite similar to those obtained from the ground in the past. The optical signals from dart leaders, from return strokes, and from continuing currents are recognizable, can be used to provide information on the fine structure of lightning, and can be used to distinguish between cloud to ground and intracloud flashes.

Development Status of the NSTAR Ion Propulsion System Power Processor

NASA Technical Reports Server (NTRS)

Hamley, John A.; Pinero, Luis R.; Rawlin, Vincent K.; Miller, John R.; Cartier, Kevin C.; Bowers, Glen E.

1995-01-01

A 0.5-2.3 kW xenon ion propulsion system is presently being developed under the NASA Solar Electric Propulsion Technology Application Readiness (NSTAR) program. This propulsion system includes a 30 cm diameter xenon ion thruster, a Digital Control Interface Unit, a xenon feed system, and a power processing unit (PPU). The PPU consists of the power supply assemblies which operate the thruster neutralizer, main discharge chamber, and ion optics. Also included are recycle logic and a digital microcontroller. The neutralizer and discharge power supplies employ a dual use configuration which combines the functions of two power supplies into one, significantly simplifying the PPU. Further simplification was realized by implementing a single thruster control loop which regulates the beam current via the discharge current. Continuous throttling is possible over a 0.5-2.3 kW output power range. All three power supplies have been fabricated and tested with resistive loads, and have been combined into a single breadboard unit with the recycle logic and microcontroller. All line and load regulation test results show the power supplies to be within the NSTAR flight PPU specified power output of 1.98 kW. The overall efficiency of the PPU, calculated as the combined efficiencies of the power supplies and controller, at 2.3 kW delivered to resistive loads was 0.90. The component was 6.16 kg. Integration testing of the neutralizer and discharge power supplies with a functional model thruster revealed no issues with discharge ignition or steady state operation.

Diagnostics of pre-breakdown light emission in a helium coplanar barrier discharge: the presence of neutral bremsstrahlung

NASA Astrophysics Data System (ADS)

Navrátil, Zdeněk; Morávek, Tomáš; Ráheľ, Jozef; Čech, Jan; Lalinský, Ondřej; Trunec, David

2017-05-01

Weak light emission (˜10-3 of active discharge signal; average count rate ˜ 1 photon s-1 nm-1) associated with surface charge relaxation during the dark phase of a helium diffuse coplanar barrier discharge was studied by optical emission spectroscopy, using a technique of phase-resolved single photon counting. The optical emission spectra of the dark phase contained luminescent bands of the dielectrics used (Al2O3, AlN) and spectral lines from the gas constituents (OH*, {{{N}}}2* , {{{N}}}2+* , He*, He{}2* , O*). During the charge relaxation event, a broad continuum appeared in the optical emission spectra, consisting of bremsstrahlung radiation and amplified luminescence of the dielectric barrier. The analysis presented suggests that the bremsstrahlung radiation originated from slow electrons colliding with neutral helium atoms. The fitting procedure we developed reproduced well the observed shape of the continuum. Moreover, it provided a method for the determination of electric field strength in the discharge during this particular phase. The electric field reached 1 kV cm-1 during the charge relaxation event.

Sensitivity of 30-cm mercury bombardment ion thruster characteristics to accelerator grid design

NASA Technical Reports Server (NTRS)

Rawlin, V. K.

1978-01-01

The design of ion optics for bombardment thrusters strongly influences overall performance and lifetime. The operation of a 30 cm thruster with accelerator grid open area fractions ranging from 43 to 24 percent, was evaluated and compared with experimental and theoretical results. Ion optics properties measured included the beam current extraction capability, the minimum accelerator grid voltage to prevent backstreaming, ion beamlet diameter as a function of radial position on the grid and accelerator grid hole diameter, and the high energy, high angle ion beam edge location. Discharge chamber properties evaluated were propellant utilization efficiency, minimum discharge power per beam amp, and minimum discharge voltage.

Characterization of pulsed metallic hydride vacuum arc discharge plasmas by optical emission spectroscopy

NASA Astrophysics Data System (ADS)

Tang, Jian; Deng, Chunfeng; Wu, Chunlei; Lu, Biao; Hu, Yonghong

2017-12-01

The characteristics of plasmas in a titanium hydride vacuum arc ion source were experimentally investigated by a temporally- and spatially-integrated optical emission spectroscopy method. A plasma emission spectral fitting model was developed to calculate the plasmas temperature and relative density of each particle component, assuming plasmas were in local thermodynamic equilibrium state and optical thin in this study. The good agreement was founded between the predicted and measured spectra in the interesting regions of 330-340 nm and 498-503 nm for Ti+ ion and Ti atom respectively, while varying the plasma temperature and density. Compared with conventional Boltzmann plot method, this method, therefore, made a significant improvement on the plasma diagnosis in dealing with the spectral profile with many lines overlapped. At the same time, to understand the mechanism of the occluded-gas vacuum arc discharge plasmas, the plasmas emission spectra, ion relative density, and temperature with different discharge conditions were studied. The results indicated that the rate of Ti metal evaporation and H desorption from the electrode would be enhanced with arc current, and the ionization temperature increased with the feed-in power of arc discharge, leading more H+ and Ti+ ions, but reducing the H+ proportion in arc discharged plasmas.

Comparison of electrical and optical characteristics in gas-phase and gas-liquid phase discharges

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

Qazi, H. I. A.; Li, He-Ping, E-mail: liheping@tsinghua.edu.cn; Zhang, Xiao-Fei

This paper presents an AC-excited argon discharge generated using a gas-liquid (two-phase) hybrid plasma reactor, which mainly consists of a powered needle electrode enclosed in a conical quartz tube and grounded deionized water electrode. The discharges in the gas-phase, as well as in the two-phase, exhibit two discharge modes, i.e., the low current glow-like diffuse mode and the high current streamer-like constrict mode, with a mode transition, which exhibits a negative resistance of the discharges. The optical emission spectral analysis shows that the stronger diffusion of the water vapor into the discharge region in the two-phase discharges boosts up themore » generation of OH (A–X) radicals, and consequently, leads to a higher rotational temperature in the water-phase plasma plume than that of the gas-phase discharges. Both the increase of the power input and the decrease of the argon flow rate result in the increase of the rotational temperature in the plasma plume of the water-phase discharge. The stable two-phase discharges with a long plasma plume in the water-phase under a low power input and gas flow rate may show a promising prospect for the degradation of organic pollutants, e.g., printing and dyeing wastewater, in the field of environmental protection.« less

Relation Between Sprite Distribution and Source Locations of VHF Pulses Derived From JEM- GLIMS Measurements

NASA Astrophysics Data System (ADS)

Sato, Mitsuteru; Mihara, Masahiro; Ushio, Tomoo; Morimoto, Takeshi; Kikuchi, Hiroshi; Adachi, Toru; Suzuki, Makoto; Yamazaki, Atsushi; Takahashi, Yukihiro

2015-04-01

JEM-GLIMS is continuing the comprehensive nadir observations of lightning and TLEs using optical instruments and electromagnetic wave receivers since November 2012. For the period between November 20, 2012 and November 30, 2014, JEM-GLIMS succeeded in detecting 5,048 lightning events. A total of 567 events in 5,048 lightning events were TLEs, which were mostly elves events. To identify the sprite occurrences from the transient optical flash data, it is necessary to perform the following data analysis: (1) a subtraction of the appropriately scaled wideband camera data from the narrowband camera data; (2) a calculation of intensity ratio between different spectrophotometer channels; and (3) an estimation of the polarization and CMC for the parent CG discharges using ground-based ELF measurement data. From a synthetic comparison of these results, it is confirmed that JEM-GLISM succeeded in detecting sprite events. The VHF receiver (VITF) onboard JEM-GLIMS uses two patch-type antennas separated by a 1.6-m interval and can detect VHF pulses emitted by lightning discharges in the 70-100 MHz frequency range. Using both an interferometric technique and a group delay technique, we can estimate the source locations of VHF pulses excited by lightning discharges. In the event detected at 06:41:15.68565 UT on June 12, 2014 over central North America, sprite was distributed with a horizontal displacement of 20 km from the peak location of the parent lightning emission. In this event, a total of 180 VHF pulses were simultaneously detected by VITF. From the detailed data analysis of these VHF pulse data, it is found that the majority of the source locations were placed near the area of the dim lightning emission, which may imply that the VHF pulses were associated with the in-cloud lightning current. At the presentation, we will show detailed comparison between the spatiotemporal characteristics of sprite emission and source locations of VHF pulses excited by the parent lightning discharges of sprites.

In vitro assessments on bacterial adhesion and corrosion performance of TiN coating on Ti6Al4V titanium alloy synthesized by multi-arc ion plating

NASA Astrophysics Data System (ADS)

Lin, Naiming; Huang, Xiaobo; Zhang, Xiangyu; Fan, Ailan; Qin, Lin; Tang, Bin

2012-07-01

TiN coating was synthesized on Ti6Al4V titanium alloy surface by multi-arc ion plating (MIP) technique. Surface morphology, cross sectional microstructure, elemental distributions and phase compositions of the obtained coating were analyzed by means of scanning electron microscope (SEM), optical microscope (OM), glow discharge optical emission spectroscope (GDOES) and X-ray diffraction (XRD). Bacterial adhesion and corrosion performance of Ti6Al4V and the TiN coating were assessed via in vitro bacterial adhesion tests and corrosion experiments, respectively. The results indicated that continuous and compact coating which was built up by pure TiN with a typical columnar crystal structure has reached a thickness of 1.5 μm. This TiN coating could significantly reduce the bacterial adhesion and enhance the corrosion resistance of Ti6Al4V substrate.

Illumination system having a plurality of movable sources

DOEpatents

Sweatt, William C.; Kubiak, Glenn D.

2002-01-01

An illumination system includes several discharge sources that are multiplexed together to reduce the amount of debris generated. The system includes: (a) a first electromagnetic radiation source array that includes a plurality of first activatable radiation source elements that are positioned on a first movable carriage; (b) a second electromagnetic radiation source array that includes a plurality of second activatable radiation source elements that are positioned on a second movable carriage; (c) means for directing electromagnetic radiation from the first electromagnetic radiation source array and electromagnetic radiation from the second electromagnetic radiation source array toward a common optical path; (d) means for synchronizing (i) the movements of the first movable carriage and of the second movable carriage and (ii) the activation of the first electromagnetic radiation source array and of the second electromagnetic radiation source array to provide an essentially continuous illumination of electromagnetic radiation along the common optical path.

Interactions between surface discharges induced by volume discharges in a dielectric barrier discharge system

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

Gao, Yenan; Dong, Lifang, E-mail: donglfhbu@163.com; Zhao, Longhu

2014-10-15

The interaction between micro-discharges involved in surface discharges (SDs) is studied in dielectric barrier discharge system. Instantaneous images taken by high speed cameras show that the SDs are induced by volume discharges (VDs). They cannot cross the midperpendicular of two neighbouring volume charges at low voltage while they stretch along it at high voltage, indicating that there is interaction between SDs. The differences of plasma parameters between SD and VD are studied by optical emission spectroscopy. The simulation of the electric fields of the wall charges accumulated by VD further confirms the existence of the interaction.

Radial-firing optical fiber tip containing conical-shaped air-pocket for biomedical applications.

PubMed

Lee, Seung Ho; Ryu, Yong-Tak; Son, Dong Hoon; Jeong, Seongmook; Kim, Youngwoong; Ju, Seongmin; Kim, Bok Hyeon; Han, Won-Taek

2015-08-10

We report a novel radial-firing optical fiber tip containing a conical-shaped air-pocket fabricated by deforming a hollow optical fiber using electric arc-discharge process. The hollow optical fiber was fusion spliced with a conventional optical fiber, simultaneously deforming into the intagliated conical-shaped region along the longitudinal fiber-axis of the fiber due to the gradual collapse of the cavity of the hollow optical fiber. Then the distal-end of the hollow optical fiber was sealed by the additional arc-discharge in order to obstruct the inflow of an external bio-substance or liquid to the inner air surface during the surgical operations, resulting in the formation of encased air-pocket in the silica glass fiber. Due to the total internal reflection of the laser beam at the conical-shaped air surface, the laser beam (λ = 632.8 nm) was deflected to the circumferential direction up to 87 degree with respect to the fiber-axis.

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.

A large-area diffuse air discharge plasma excited by nanosecond pulse under a double hexagon needle-array electrode.

PubMed

Liu, Zhi-Jie; Wang, Wen-Chun; Yang, De-Zheng; Wang, Sen; Zhang, Shuai; Tang, Kai; Jiang, Peng-Chao

2014-01-01

A large-area diffuse air discharge plasma excited by bipolar nanosecond pulse is generated under a double hexagon needle-array electrode at atmospheric pressure. The images of the diffuse discharge, electric characteristics, and the optical emission spectra emitted from the diffuse air discharge plasma are obtained. Based on the waveforms of pulse voltage and current, the power consumption, and the power density of the diffuse air discharge plasma are investigated under different pulse peak voltages. The electron density and the electron temperature of the diffuse plasma are estimated to be approximately 1.42×10(11) cm(-3) and 4.4 eV, respectively. The optical emission spectra are arranged to determine the rotational and vibrational temperatures by comparing experimental with simulated spectra. Meanwhile, the rotational and vibrational temperatures of the diffuse discharge plasma are also discussed under different pulse peak voltages and pulse repetition rates, respectively. In addition, the diffuse air discharge plasma can form an area of about 70×50 mm(2) on the surface of dielectric layer and can be scaled up to the required size. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Merging Satellite Optical Sensors and Radar Altimetry for Daily River Discharge Estimation

NASA Astrophysics Data System (ADS)

Tarpanelli, A.; Santi, E. S.; Tourian, M. J.; Filippucci, P.; Amarnath, G.; Brocca, L.; Benveniste, J.

2017-12-01

River discharge is a fundamental physical variable of the hydrological cycle and notwithstanding its importance the monitoring of the flow in many parts of the Earth is still an open issue. Satellite sensors have great potential in offering new ways to monitor river discharge, because they guarantees regular, uniform and global measurements for long period thanks to the large number of satellites launched during the last twenty-five years. The multi-mission approach has been becoming a useful tool to integrate measurements and intensify the number of samples in space and time. In this study, we investigated the possibility to merge data from optical, i.e. Near InfraRed bands (from MODIS, MERIS, Landsat, and OLCI) and altimetry data (from Topex-Poseidon, Envisat/RA-2, Jason-2, SARAL/AltiKa and CryoSat-2) for estimating daily river discharge in Nigeria and Italy. The merging procedure is carried out by using artificial neural networks. Regarding the optical sensors, results are more affected by the temporal resolution than the spatial resolution. Landsat fails in the estimation of extreme events missing most of the peak values because of the long revisit time (14-16 days). Better performances are obtained with the Near InfraRed bands from MODIS and MERIS that give similar results in river discharge estimation. Finally, the multi-mission approach involving also radar altimetry data is found to be the most reliable tool to estimate river discharge in medium to large rivers.

Characteristics of a novel nanosecond DBD microplasma reactor for flow applications

NASA Astrophysics Data System (ADS)

Elkholy, A.; Nijdam, S.; van Veldhuizen, E.; Dam, N.; van Oijen, J.; Ebert, U.; de Goey, L. Philip H.

2018-05-01

We present a novel microplasma flow reactor using a dielectric barrier discharge (DBD) driven by repetitive nanosecond high-voltage pulses. Our DBD-based geometry can generate a non-thermal plasma discharge at atmospheric pressure and below in a regular pattern of micro-channels. This reactor can work continuously up to about 100 min in air, depending on the pulse repetition rate and operating pressure. We here present the geometry and main characteristics of the reactor. Pulse energies of 1.46 and 1.3 μJ per channel at atmospheric pressure and 50 mbar, respectively, have been determined by time-resolved measurements of current and voltage. Time-resolved optical emission spectroscopy measurements have been performed to calculate the relative species concentrations and temperatures (vibrational and rotational) of the discharge. The effects of the operating pressure and flow velocity on the discharge intensity have been investigated. In addition, the effective reduced electric field strength {(E/N)}eff} has been obtained from the intensity ratio of vibronic emission bands of molecular nitrogen at different operating pressures and different locations. The derived {(E/N)}eff} increases gradually from about 550 to 4600 Td when decreasing the pressure from 1 bar to 100 mbar. Below 100 mbar, further pressure reduction results in a significant increase in {(E/N)}eff} up to about 10000 Td at 50 mbar.

Light sensitive memristor with bi-directional and wavelength-dependent conductance control

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

Maier, P.; Hartmann, F., E-mail: fabian.hartmann@physik.uni-wuerzburg.de; Emmerling, M.

2016-07-11

We report the optical control of localized charge on positioned quantum dots in an electro-photo-sensitive memristor. Interband absorption processes in the quantum dot barrier matrix lead to photo-generated electron-hole-pairs that, depending on the applied bias voltage, charge or discharge the quantum dots and hence decrease or increase the conductance. Wavelength-dependent conductance control is observed by illumination with red and infrared light, which leads to charging via interband and discharging via intraband absorption. The presented memristor enables optical conductance control and may thus be considered for sensory applications in artificial neural networks as light-sensitive synapses or optically tunable memories.

Kinetic analysis of rare gas metastable production and optically pumped Xe lasers

NASA Astrophysics Data System (ADS)

Demyanov, A. V.; Kochetov, I. V.; Mikheyev, P. A.; Azyazov, V. N.; Heaven, M. C.

2018-01-01

Optically pumped all-rare-gas lasers use metastable rare gas atoms as the lasing species in mixtures with He or Ar buffer gas. The metastables are generated in a glow discharge, and we report model calculations for the optimal production of Ne*, Ar*, Kr* and Xe*. Discharge efficiency was estimated by solving the Boltzmann equation. Laser efficiency, gain and output power of the CW optically pumped Xe laser were assessed as functions of heavier rare gas content, pressure, optical pump intensity and the optical path length. It was found that, for efficient operation the heavier rare gas content has to be of the order of one percent or less, and the total pressure—in the range 0.3-1.5 atm. Output power and specific discharge power increase approximately linearly with pump intensity over the output range from 300-500 W cm-2. Ternary mixtures Xe:Ar:He were found to be the most promising. Total laser efficiency was found to be nearly the same for pumping the 2p8 or 2p9 state, reaching 61%-70% for a pump intensity of ~720 W cm-2 when the Xe fraction was in the range 0.001 ÷ 0.01 and Ar fraction—0.1 ÷ 0.5. However, when the 2p8 state was pumped, the maximum total efficiency occurred at larger pressures than for pumping of the 2p9 state. The discharge power density required to sustain a sufficient Xe* number density was in the range of tens of watts per cubic centimeter for 50% Ar in the mixture.

Optical and structural properties of colloidal zirconia nanoparticles prepared by arc discharge in liquid

NASA Astrophysics Data System (ADS)

Peymani forooshani, Reza; Poursalehi, Reza; Yourdkhani, Amin

2018-01-01

Zirconia is one of the important ceramic materials with unique properties such as high melting point, high ionic conductivity, high mechanical properties and low thermal conductivity. Therefore, zirconia is one of the useful materials in refractories, thermal barriers, cutting tools, oxygen sensors electrolytes, catalysis, catalyst supports and solid oxide fuel cells. Recently, direct current (DC) arc discharge is extensively employed to synthesis of metal oxide nanostructures in liquid environments. The aim of this work is the synthesis of colloidal zirconia nanoparticles by DC arc discharge method in water as a medium. Arc discharge was ignited between two pure zirconium electrodes in water. Optical and structural properties of prepared colloidal nanoparticles were investigated. Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and UV-visible spectroscopy, were employed for characterization of particle size, morphology, crystal structure and optical properties, respectively. SEM images demonstrate that the nanoparticles are spherical in shape with an average size lower than 38 nm. The XRD patterns of the nanoparticles were consistent with tetragonal and monoclinic zirconia crystal structures. The optical transmission spectra of the colloidal solution show optical characteristic of zirconia nanoparticles as a wide band gap semiconductor with no absorption peak in visible wavelength with the considerable amount of oxygen deficiency. Oxidation of colloidal nanoparticles in water could be explained via reaction with either dissociated oxygen from water in hot plasma region or with dissolved oxygen in water. The results provide a simple and flexible method for preparation of zirconia nanoparticles with a capability of mass production without environmental footprints.

Atmospheric pressure helium afterglow discharge detector for gas chromatography

DOEpatents

Rice, G.; D'Silva, A.P.; Fassel, V.A.

1985-04-05

An apparatus for providing a simple, low-frequency, electrodeless discharge system for atmospheric pressure afterglow generation. A single quartz tube through which a gas mixture is passed is extended beyond a concentric electrode positioned thereabout. A grounding rod is placed directly above the tube outlet to permit optical viewing of the discharge between the electrodes.

Atmospheric pressure helium afterglow discharge detector for gas chromatography

DOEpatents

Rice, Gary; D'Silva, Arthur P.; Fassel, Velmer A.

1986-05-06

An apparatus for providing a simple, low-frequency electrodeless discharge system for atmospheric pressure afterglow generation. A single quartz tube through which a gas mixture is passed is extended beyond a concentric electrode positioned thereabout. A grounding rod is placed directly above the tube outlet to permit optical viewing of the discharge between the electrodes.

40 CFR 52.1988 - Air contaminant discharge permits.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Air contaminant discharge permits. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Oregon § 52.1988 Air contaminant... other provisions contained in Air Contaminant Discharge Permits issued by the State in accordance with...

Observation and interpretation of energy efficient, diffuse direct current glow discharge at atmospheric pressure

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

Tang, Jie, E-mail: tangjie1979@opt.ac.cn; Jiang, Weiman; Wang, Yishan

2015-08-24

A diffuse direct-current glow discharge was realized with low energy consumption and high energy utilization efficiency at atmospheric pressure. The formation of diffuse discharge was demonstrated by examining and comparing the electrical properties and optical emissions of plasmas. In combination with theoretical derivation and calculation, we draw guidelines that appearance of nitrogen ions at low electron density is crucial to enhance the ambipolar diffusion for the expansion of discharge channel and the increasing ambipolar diffusion near the cathode plays a key role in the onset of diffuse discharge. An individual-discharge-channel expansion model is proposed to explain the diffuse discharge formation.

Transparent electrode for optical switch

DOEpatents

Goldhar, Julius; Henesian, Mark A.

1986-01-01

A low pressure gas electrode utilizing ionized gas in a glow discharge regime forms a transparent electrode for electro-optical switches. The transparent electrode comprises a low pressure gas region on both sides of the crystal. When the gas is ionized, e.g., by a glow discharge in the low pressure gas, the plasma formed is a good conductor. The gas electrode acts as a highly uniform conducting electrode. Since the plasma is transparent to a high energy laser beam passing through the crystal, the electrode is a transparent electrode. A crystal exposed from two sides to such a plasma can be charged up uniformly to any desired voltage. The plasma can be created either by the main high voltage pulser used to charge up the crystal or by auxiliary discharges or external sources of ionization. A typical configuration utilizes 10 torr argon in the discharge region adjacent to each crystal face.

Demonstration of a CW diode-pumped Ar metastable laser operating at 4  W.

PubMed

Han, J; Heaven, M C; Moran, P J; Pitz, G A; Guild, E M; Sanderson, C R; Hokr, B

2017-11-15

Optically pumped rare gas lasers are being investigated as potential high-energy, high beam quality systems. The lasing medium consists of rare gas atoms (Rg=Ne, Ar, Kr, or Xe) that have been electric discharge excited to the metastable np 5 (n+1)s P3 2 state. Following optical excitation, helium (He) at pressures of 200-1000 Torr is used as the energy transfer agent to create a population inversion. The primary technical difficulty for this scheme is the discharge production of sufficient Rg* metastables in the presence of >200  Torr of He. In this Letter, we describe a pulsed discharge that yields >10 13   cm -3 Ar* in the presence of He at total pressures up to 750 Torr. Using this discharge, a diode-pumped Ar* laser providing 4.1 W has been demonstrated.

Optical and application study of gas-liquid discharge excited by bipolar nanosecond pulse in atmospheric air.

PubMed

Wang, Sen; Wang, Wen-chun; Yang, De-zheng; Liu, Zhi-jie; Zhang, Shuai

2014-10-15

In this study, a bipolar nanosecond pulse with 20ns rising time is employed to generate air gas-liquid diffuse discharge plasma with room gas temperature in quartz tube at atmospheric pressure. The image of the discharge and optical emission spectra of active species in the plasma are recorded. The plasma gas temperature is determined to be approximately 390K by compared the experimental spectra with the simulated spectra, which is slightly higher than the room temperature. The result indicated that the gas temperature rises gradually with pulse peak voltage increasing, while decreases slightly with the electrode gap distance increasing. As an important application, bipolar nanosecond pulse discharge is used to sterilize the common microorganisms (Actinomycetes, Candida albicans and Escherichia coli) existing in drinking water, which performs high sterilization efficiency. Copyright © 2014 Elsevier B.V. All rights reserved.

Schlieren optical visualization for transient EHD induced flow in a stratified dielectric liquid under gas-phase ac corona discharges

NASA Astrophysics Data System (ADS)

Ohyama, R.; Inoue, K.; Chang, J. S.

2007-01-01

A flow pattern characterization of electrohydrodynamically (EHD) induced flow phenomena of a stratified dielectric fluid situated in an ac corona discharge field is conducted by a Schlieren optical system. A high voltage application to a needle-plate electrode arrangement in gas-phase normally initiates a conductive type EHD gas flow. Although the EHD gas flow motion initiated from the corona discharge electrode has been well known as corona wind, no comprehensive study has been conducted for an EHD fluid flow motion of the stratified dielectric liquid that is exposed to the gas-phase ac corona discharge. The experimentally observed result clearly presents the liquid-phase EHD flow phenomenon induced from the gas-phase EHD flow via an interfacial momentum transfer. The flow phenomenon is also discussed in terms of the gas-phase EHD number under the reduced gas pressure (reduced interfacial momentum transfer) conditions.

Measurements of Temperature and Hydroxyl Radical Generation/Decay in Lean Fuel-Air Mixtures Excited by a Repetitively Pulsed Nanosecond Discharge

DTIC Science & Technology

2013-04-10

discharge, a region approximately 15-mm- long, via a right angle prism and fused silica lenses , and directed to a photomultiplier tube (PMT) (Hamamatsu...A 60-mm-long, right- angle fused silica prism is placed along the channel to provide optical ac- cess from the side (see Fig. 1). The entire assembly...and exit windows set at Brewster’s angle . Note that using Rayleigh scattering calibration requires no change in optical alignment, therefore mitigating

Ion source design for industrial applications

NASA Technical Reports Server (NTRS)

Kaufman, H. R.; Robinson, R. S.

1981-01-01

The design of broad-beam industrial ion sources is described. The approach used emphasizes refractory metal cathodes and permanent-magnet multipole discharge chambers. Design procedures and sample calculations are given for the discharge chamber, ion optics, cathodes, and magnetic circuit. Hardware designs are included for the isolator, cathode supports, anode supports, pole-piece assembly, and ion-optics supports. There are other ways of designing most ion source components, but the designs presented are representative of current technology and adaptable to a wide range of configurations.

Towards Optical Partial Discharge Detection with Micro Silicon Photomultipliers

PubMed Central

Ren, Ming; Song, Bo; Dong, Ming

2017-01-01

Optical detection is reliable in intrinsically characterizing partial discharges (PDs). Because of the great volume and high-level power supply of the optical devices that can satisfy the requirements in photosensitivity, optical PD detection can merely be used in laboratory studies. To promote the practical application of the optical approach in an actual power apparatus, a silicon photomultiplier (SiPM)-based PD sensor is introduced in this paper, and its basic properties, which include the sensitivity, pulse resolution, correlation with PD severity, and electromagnetic (EM) interference immunity, are experimentally evaluated. The stochastic phase-resolved PD pattern (PRPD) for three typical insulation defects are obtained by SiPM PD detector and are compared with those obtained using a high-frequency current transformer (HFCT) and a vacuum photomultiplier tube (PMT). Because of its good performances in the above aspects and its additional advantages, such as the small size, low power supply, and low cost, SiPM offers great potential in practical optical PD monitoring. PMID:29125544

Towards Optical Partial Discharge Detection with Micro Silicon Photomultipliers.

PubMed

Ren, Ming; Zhou, Jierui; Song, Bo; Zhang, Chongxing; Dong, Ming; Albarracín, Ricardo

2017-11-10

Optical detection is reliable in intrinsically characterizing partial discharges (PDs). Because of the great volume and high-level power supply of the optical devices that can satisfy the requirements in photosensitivity, optical PD detection can merely be used in laboratory studies. To promote the practical application of the optical approach in an actual power apparatus, a silicon photomultiplier (SiPM)-based PD sensor is introduced in this paper, and its basic properties, which include the sensitivity, pulse resolution, correlation with PD severity, and electromagnetic (EM) interference immunity, are experimentally evaluated. The stochastic phase-resolved PD pattern (PRPD) for three typical insulation defects are obtained by SiPM PD detector and are compared with those obtained using a high-frequency current transformer (HFCT) and a vacuum photomultiplier tube (PMT). Because of its good performances in the above aspects and its additional advantages, such as the small size, low power supply, and low cost, SiPM offers great potential in practical optical PD monitoring.

Study on optical emission analysis of AC air water discharges under He, Ar and N2 environments

NASA Astrophysics Data System (ADS)

Park, J. Y.; Kostyuk, P. V.; Han, S. B.; Kim, J. S.; Vu, C. N.; Lee, H. W.

2006-09-01

In this paper, hybrid air-water discharges were used to develop an optimal condition for providing a high level of water decomposition for hydrogen evolution. Electrical and optical phenomena accompanying the discharges were investigated along with feeding gases, flow rates and point-to-plane electrode gap distance. The experiments were primarily focused on the optical emission of the near UV range, providing a sufficient energy threshold for water dissociation and excitation. The OH(A 2Σ+ → X 2Π, Δν = 0) band optical emission intensity indicated the presence of plasma chemical reactions involving hydrogen formation. Despite the fact that energy input was high, the OH(A-X) optical emission was found to be negligible at the zero gap distance between the tip of the metal rod and water surface. In the gas atmosphere saturated with water vapour the OH(A-X) intensity was relatively high compared with the liquid and transient phases although the optical emission strongly depended on the flow rate and type of feeding gas. The gas phase was found to be more favourable because of less energy consumption in the cases of He and Ar carrier gases, and quenching mechanisms of oxygen in the N2 carrier gas atmosphere, preventing hydrogen from recombining with oxygen. In the gas phase the discharge was at a steady state, in contrast to the other phases, in which bubbles interrupted propagation of the plasma channel. Optical emission intensity of OH(A-X) band increased according to the flow rate or residence time of the He feeding gas. Nevertheless, a reciprocal tendency was acquired for N2 and Ar carrier gases. The peak value of OH(A-X) band optical emission intensity was observed near the water surface; however in the cases of Ar and N2 with a 0.5 SLM flow rate, it was shifted below the water surface. Rotational temperature was estimated to be in the range of 900-3600 K, according to the carrier gas and flow rate, which is sufficient for hydrogen production.

An experimental study of atmospheric pressure dielectric barrier discharge (DBD) in argon

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

Subedi, D. P.; Tyata, R. B.; Shrestha, R.

2014-03-05

In this paper, experimental results on atmospheric pressure argon dielectric barrier discharge (DBD) have been presented. The discharge was generated using a high voltage (0 to 20 kV) power supply operating at frequency of 10 to 30 kHz and was studied by means of electrical and optical measurements. A homogeneous and steady discharge was observed between the electrodes with gap spacing from 1 mm to 3 mm and with a dielectric barrier of thickness 1.5 mm while argon gas is fed at a controlled flow rate of 2liter per min. The electron temperature (T{sub e}) and electron density (n{sub e})more » of the plasma have been determined by means of optical emission spectroscopy. Our results show that the electron density is of the order of 10{sup 16} cm{sup −3} while the electron temperature is estimated to be ∼ 1 eV. The homogeneity and non-thermal nature of the discharge were utilized in the investigation of the change in wettabilty of a polymer sample subjected to the treatment by the discharge. Contact angle analysis showed that the discharge was effective in improving the wettability of low density Polyethylene (LDPE) polymer sample after the treatment.« less

The measurement of argon metastable atoms in the barrier discharge plasma

NASA Astrophysics Data System (ADS)

Ghildina, Anna R.; Mikheyev, Pavel Anatolyevich; Chernyshov, Aleksandr Konstantinovich; Lunev, Nikolai Nikolaevich; Azyazov, Valeriy Nikolaevich

2018-04-01

The mandatory condition for efficient operation of an optically-pumped all-rare-gas laser (OPRGL) is the presence of rare gas metastable atoms in the discharge plasma with number density of the order of 1012-1013 cm-3. This requirement mainly depends on the choice of a discharge system. In this study the number density values of argon metastable atoms were obtained in the condition of the dielectric-barrier discharge (DBD) at an atmospheric pressure.

Longitudinal discharge laser baffles

DOEpatents

Warner, Bruce E.; Ault, Earl R.

1994-01-01

The IR baffles placed between the window and the electrode of a longitudinal discharge laser improve laser performance by intercepting off-axis IR radiation from the laser and in doing so reduce window heating and subsequent optical distortion of the laser beam.

Ocean outfall plume characterization using an Autonomous Underwater Vehicle.

PubMed

Rogowski, Peter; Terrill, Eric; Otero, Mark; Hazard, Lisa; Middleton, William

2013-01-01

A monitoring mission to map and characterize the Point Loma Ocean Outfall (PLOO) wastewater plume using an Autonomous Underwater Vehicle (AUV) was performed on 3 March 2011. The mobility of an AUV provides a significant advantage in surveying discharge plumes over traditional cast-based methods, and when combined with optical and oceanographic sensors, provides a capability for both detecting plumes and assessing their mixing in the near and far-fields. Unique to this study is the measurement of Colored Dissolved Organic Matter (CDOM) in the discharge plume and its application for quantitative estimates of the plume's dilution. AUV mission planning methodologies for discharge plume sampling, plume characterization using onboard optical sensors, and comparison of observational data to model results are presented. The results suggest that even under variable oceanic conditions, properly planned missions for AUVs equipped with an optical CDOM sensor in addition to traditional oceanographic sensors, can accurately characterize and track ocean outfall plumes at higher resolutions than cast-based techniques.

Dynamics of spiral patterns in gas discharge detected by optical method

NASA Astrophysics Data System (ADS)

Yang, Fan; Wang, Mingyi; Liu, Shuhua

2016-09-01

The dynamics behavior of spiral patterns is investigated in gas discharge using optical method. Rich kinks of spiral patterns are obtained and the formation and evolution process is investigated. The process of pattern formation is breakdown -> hexagon -> bee comb-like -> strip -> spiral -> chaos. Spiral pattern always formed after the strip pattern. It is found that the temperature of the water electrodes plays an important role in the spiral patterns formation. When it exceeds 20°C no spiral has been obtained. The discharge current waveform and the emission spectrum of the discharge have been measured when the filaments self-organized in spiral pattern. Electron excited temperature of forming spiral pattern is calculated using intensity ratio method. It is found that the electron excited temperature of spiral pattern increase as the power supply frequency increased. Relation between wavelength and discharge parameter has been measured. It shows that the wavelength of spiral pattern increases as the discharge gap increases, and decreases as the air ratio mixed in argon increases. Accompanying measurements proved that the wavelength is approximately linear to the square root of the spiral rotating period .This work has useful reference value for studying pattern dynamics.

Influence of an optical pulsed discharge on the structure of a supersonic air flow

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

Malov, A N; Orishich, A M

We present the results of investigation of the parameters of an optical pulsed discharge (OPD) and their relation with gasdynamic parameters of a supersonic flow and with characteristics of laser radiation. For the first time the discrete objects are detected in the OPD by an optical method, namely, low-density caverns moving along with the flow. The propagation velocity of the thermal track arising in a supersonic flow under the action of the OPD is measured. It is found that at a pulse repetition rate of 90 – 120 kHz the caverns unite into a single plasma jet. (laser applications andmore » other topics in quantum electronics)« less

Minding the gap: Interprofessional communication during inpatient and post discharge chasm care.

PubMed

Scotten, Mitzi; Manos, Eva LaVerne; Malicoat, Allison; Paolo, Anthony M

2015-07-01

Poor communication is cited as a main cause of poor patient outcomes and errors in healthcare, and clear communication can be especially critical during transitions such as discharge. In this project, communication was standardized for clarity, and techniques were implemented to continue care from inpatient, to discharge, across the post-discharge chasm, to hand-off with the primary care provider (PCP). The interprofessional (IP) quality improvement initiative included: (1) evidence-based teamwork system; (2) in situ simulation; (3) creation of an IP model of care; and (4) innovations in use of telehealth technology to continue care post-discharge. Measures inpatient/parent satisfaction and the attitudes of the care team have improved. Traditional methods of communication and transition do not meet patient or healthcare provider needs. Communication must be standardized to be understandable and be used by the IP team. Care must continue post-discharge by utilizing technology to increase quality and continuity of care. Improving and practicing communication skills may lead to reductions in healthcare errors and readmissions, and may decrease the length of stay and improve satisfaction of care teams. Published by Elsevier Ireland Ltd.

Water Resources Data, Florida, Water Year 2003, Volume 4. Northwest Florida

USGS Publications Warehouse

prepared by Blum, Darlene A.; Alvarez, A. Ernie

2004-01-01

The U.S. Geological Survey (USGS), in cooperation with Federal, State, and local agencies, obtains a large amount of data on the water resources of the State of Florida each water year. These data, accumulated during many water years, constitute a valuable database that is used by water-resources managers, emergency-management officials, and many others to develop an improved understanding of water resources within the State. This report series for the 2003 water year for the state of Florida consists of records for continuous or daily discharge for 385 streams, periodic discharge for 13 streams, continuous or daily stage for 255 streams, periodic stage for 13 streams, peak stage and discharge for 36 streams, continuous or daily elevations for 13 lakes, periodic elevations for 46 lakes, continuous ground-water levels for 441 wells, periodic ground-water levels for 1,227 wells, and quality-of-water for 133 surface-water sites and 308 wells. This volume (Volume 4, Northwest Florida)contains records of continuous or daily discharge for 72 streams, periodic discharge for 3 stream, continuous or daily stage for 13 streams, periodic stage for 0 stream, peak stage and discharge for 28 streams, continuous or daily elevations for 1 lake, periodic elevations for 0 lakes, continuous ground-water levels for 3 wells, periodic ground-water levels for 0 wells, and quality-of-water for 3 surface-water sites and 0 wells. These data represent the National Water Data System records collected by the U.S. Geological Survey and cooperating local, State, and Federal agencies in Florida.

High-frequency in situ optical measurements during a storm event: Assessing relationships between dissolved organic matter, sediment concentrations, and hydrologic processes

USGS Publications Warehouse

Saraceno, John F.; Pellerin, Brian A.; Downing, Bryan D.; Boss, Emmanuel; Bachand, Philip A. M.; Bergamaschi, Brian A.

2009-01-01

Dissolved organic matter (DOM) dynamics during storm events has received considerable attention in forested watersheds, but the extent to which storms impart rapid changes in DOM concentration and composition in highly disturbed agricultural watersheds remains poorly understood. In this study, we used identical in situ optical sensors for DOM fluorescence (FDOM) with and without filtration to continuously evaluate surface water DOM dynamics in a 415 km2agricultural watershed over a 4 week period containing a short-duration rainfall event. Peak turbidity preceded peak discharge by 4 h and increased by over 2 orders of magnitude, while the peak filtered FDOM lagged behind peak turbidity by 15 h. FDOM values reported using the filtered in situ fluorometer increased nearly fourfold and were highly correlated with dissolved organic carbon (DOC) concentrations (r2 = 0.97), providing a highly resolved proxy for DOC throughout the study period. Discrete optical properties including specific UV absorbance (SUVA254), spectral slope (S290–350), and fluorescence index (FI) were also strongly correlated with in situ FDOM and indicate a shift toward aromatic, high molecular weight DOM from terrestrially derived sources during the storm. The lag of the peak in FDOM behind peak discharge presumably reflects the draining of watershed soils from natural and agricultural landscapes. Field and experimental evidence showed that unfiltered FDOM measurements underestimated filtered FDOM concentrations by up to ∼60% at particle concentrations typical of many riverine systems during hydrologic events. Together, laboratory and in situ data provide insights into the timing and magnitude of changes in DOM quantity and quality during storm events in an agricultural watershed, and indicate the need for sample filtration in systems with moderate to high suspended sediment loads.

Continuous Supersonic Expansion Discharge Source for High-Precision Mid-Infrared Spectroscopy of Cold Molecular Ions

NASA Astrophysics Data System (ADS)

Talicska, Courtney; Porambo, Michael; McCall, Benjamin J.

2015-06-01

The low temperatures and pressures of the interstellar medium provide an ideal environment for gas phase ion-neutral reactions that play an essential role in the chemistry of the universe. High-precision laboratory spectra of molecular ions are necessary to facilitate new astronomical discoveries and provide a deeper understanding of interstellar chemistry, but forming ions in measurable quantities in the laboratory has proved challenging. Even when cryogenically cooled, the high temperatures and pressures of typical discharge cells lead to diluted and congested spectra from which extracting chemical information is difficult. Here we overcome this challenge by coupling an electric discharge to a continuous supersonic expansion source to form ions cooled to low temperatures. The ion production abilities of the source have been demonstrated previously as ion densities on the order of 1010-1012 cm-3 have been observed for H3+.a With a smaller rotational constant and the expectation that it will be formed with comparable densities, HN2+ is used as a reliable measure of the cooling abilities of the source. Ions are probed through the use of a widely tunable mid-infrared (3-5 μm) spectrometer based on light formed by difference frequency generation and noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS).b To improve the sensitivity of the instrument the discharge is electrically modulated and the signal is fed into a lock-in amplifier before being recorded by a custom data acquisition program. Rovibrational transitions of H3+ and HN2+ have been recorded, giving rotational temperatures of 80-120 K and 35-40 K, respectively. With verification that the source is producing rotationally cold ions, we move toward the study of primary ions of more astronomical significance, including H2CO+. aK. N. Crabtree, C. A. Kaufman, and B. J. McCall, Rev. Sci. Instrum. 81, 086103 (2010). bM. W. Porambo, B. M. Siller, J. M. Pearson, and B. J. McCall, Opt. Lett. 37, 4422 (2012)

Optical and electrical characteristics of hollow-needle to plate atmospheric-pressure discharge in nitrogen

NASA Astrophysics Data System (ADS)

Simek, Milan; Schmidt, Jiri; Pekarek, Stanislav; Khun, Josef

2006-10-01

We have studied basic optical and electrical characteristics of the DC hollow needle to plate electrical discharge enhanced by the gas flow through the needle. Substantial advantage of this arrangement is that all gas supplied to the discharge passes through the discharge zone and therefore it is affected by plasma chemical processes. Depending on the energy dissipated between electrodes, we previously observed two basic discharge regimes: a) DC corona and b) DC corona superimposed with pulsed filamentary streamers [1]. In this work, we have analyzed radiation induced by filamentary streamers. In addition to nitrogen emissions driven by electron impact processes we have detected emission induced by specific energy transfer processes [2]. We have also determined mean repetition frequency of filamentary streamers (0.1-15 kHz) for the needle-to-plane gap and for the nitrogen flow through the needle ranging between 2-6 mm and 1-10 slm, respectively. [1] M. Simek and S.Pekarek, GEC 2005, Bul. Am. Phys. Soc. 50, 29, (2005) ; [2] M. Simek at al, Pure Appl. Chem. 78, 1213, (2006).

Nighttime observations of thunderstorm electrical activity from a high altitude airplane

NASA Technical Reports Server (NTRS)

Brook, M.; Rhodes, C.; Vaughan, O. H., Jr.; Orville, R. E.; Vonnegut, B.

1984-01-01

Photographs from a NASA U-2 airplane flying over nocturnal thunderstorms show frequent lightning activity in the upper part of the cloud. In some cases, unobscured segments of lightning channels 1 km or longer are visible in clear air around and above the cloud. Multiple images of lightning channels indicate multiple discharges in the same channel. Photographs taken through a diffraction grating show that the lightning has a spectrum similar to that observed in the lower troposphere. Lightning spectra obtained with a slitless line-scan spectrometer show strong singly ionized nitrogen emissions at 463.0 and 500.5 nm. Field changes measured with an electric field-change meter correlate with pulses measured with a photocell optical system. Optical signals corresponding to dart leader, return stroke, and continuing current events are readily distinguished in the scattered light emerging from the cloud surface. The variation of light intensity with time in lightning events is consistent with predicted modification of optical lightning signals by clouds. It appears that satellite based optical sensor measurements cannot provide reliable information on current rise times in return strokes. On the other hand, discrimination between cloud-to-ground and intracloud flashes and the counting of ground strokes is possible using the optical pulse pairs which have been identified with leader, return-stroke events in the cloud-to-ground flashes studied.

Characteristics of radio-frequency atmospheric pressure dielectric-barrier discharge with dielectric electrodes

NASA Astrophysics Data System (ADS)

Hussain, S.; Qazi, H. I. A.; Badar, M. A.

2014-03-01

An experimental investigation to characterize the properties and highlight the benefits of atmospheric pressure radio-frequency dielectric-barrier discharge (rf DBD) with dielectric electrodes fabricated by anodizing aluminium substrate is presented. The current-voltage characteristics and millisecond images are used to distinguish the α and γ modes. This atmospheric rf DBD is observed to retain the discharge volume without constriction in γ mode. Optical emission spectroscopy demonstrates that the large discharge current leads to more abundant reactive species in this plasma source.

40 CFR 52.1988 - Air contaminant discharge permits.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Air contaminant discharge permits. 52.1988 Section 52.1988 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Oregon § 52.1988 Air contaminant...

Experimentally Determined Plasma Parameters in a 30 cm Ion Engine

NASA Technical Reports Server (NTRS)

Sengupta, Anita; Goebel, Dan; Fitzgerald, Dennis; Owens, Al; Tynan, George; Dorner, Russ

2004-01-01

Single planar Langmuir probes and fiber optic probes are used to concurrently measure the plasma properties and neutral density variation in a 30cm diameter ion engine discharge chamber, from the immediate vicinity of the keeper to the near grid plasma region. The fiber optic probe consists of a collimated optical fiber recessed into a double bore ceramic tube fitted with a stainless steel light-limiting window. The optical fiber probe is used to measure the emission intensity of excited neutral xenon for a small volume of plasma, at various radial and axial locations. The single Langmuir probes, are used to generate current-voltage characteristics at a total of 140 spatial locations inside the discharge chamber. Assuming a maxwellian distribution for the electron population, the Langmuir probe traces provide spatially resolved measurements of plasma potential, electron temperature, and plasma density. Data reduction for the NSTAR TH8 and TH15 throttle points indicates an electron temperature range of 1 to 7.9 eV and an electron density range of 4e10 to le13 cm(sup -3), throughout the discharge chamber, consistent with the results in the literature. Plasma potential estimates, computed from the first derivative of the probe characteristic, indicate potential from 0.5V to 11V above the discharge voltage along the thruster centerline. These values are believed to be excessively high due to the sampling of the primary electron population along the thruster centerline. Relative neutral density profiles are also obtained with a fiber optic probe sampling photon flux from the 823.1 nm excited to ground state transition. Plasma parameter measurements and neutral density profiles will be presented as a function of probe location and engine discharge conditions. A discussion of the measured electron energy distribution function will also be presented, with regards to variation from pure maxwellian. It has been found that there is a distinct primary population found along the thruster centerline, which causes estimates of electron temperature, electron density, and plasma potential, to err on the high side, due this energetic population. Computation of the energy distribution fimction of the plasma clearly indicates the presence of primaries, whose presence become less obvious with radial distance from the main discharge plume.

Improved high-intensity microwave discharge lamp for atomic resonance absorption and fluorescence spectrometry.

PubMed

Lifshitz, A; Skinner, G B; Wood, D R

1978-09-01

An unusually good combination of high intensity and narrow line has been achieved in a microwave discharge lamp by placing the optical window in the center of the microwave cavity. Construction details and performance characteristics are described.

Study of wire electrical discharge machined folded-up corner cube retroreflector with a tunable cantilever beam

NASA Astrophysics Data System (ADS)

Chen, Yu-Fan; Wang, Yen-Hung; Tsai, Jui-che

2018-03-01

This work has developed an approach to construct a corner cube retroreflector (CCR). A two-dimensional cutout pattern is first fabricated with wire electrical discharge machining process. It is then folded up into a three-dimensional CCR suspended on a cantilever beam. The folded-up CCR may be driven through external actuators for optical modulation; it can also mechanically respond to perturbation, acceleration, etc., to function as a sensor. Mechanical (static and dynamic modeling) and optical (ray tracing) analyses are also performed.

Wavelength Scanning with a Tilting Interference Filter for Glow-Discharge Elemental Imaging.

PubMed

Storey, Andrew P; Ray, Steven J; Hoffmann, Volker; Voronov, Maxim; Engelhard, Carsten; Buscher, Wolfgang; Hieftje, Gary M

2017-06-01

Glow discharges have long been used for depth profiling and bulk analysis of solid samples. In addition, over the past decade, several methods of obtaining lateral surface elemental distributions have been introduced, each with its own strengths and weaknesses. Challenges for each of these techniques are acceptable optical throughput and added instrumental complexity. Here, these problems are addressed with a tilting-filter instrument. A pulsed glow discharge is coupled to an optical system comprising an adjustable-angle tilting filter, collimating and imaging lenses, and a gated, intensified charge-coupled device (CCD) camera, which together provide surface elemental mapping of solid samples. The tilting-filter spectrometer is instrumentally simpler, produces less image distortion, and achieves higher optical throughput than a monochromator-based instrument, but has a much more limited tunable spectral range and poorer spectral resolution. As a result, the tilting-filter spectrometer is limited to single-element or two-element determinations, and only when the target spectral lines fall within an appropriate spectral range and can be spectrally discerned. Spectral interferences that result from heterogeneous impurities can be flagged and overcome by observing the spatially resolved signal response across the available tunable spectral range. The instrument has been characterized and evaluated for the spatially resolved analysis of glow-discharge emission from selected but representative samples.

High-irradiance reactor design with practical unfolded optics

NASA Astrophysics Data System (ADS)

Feuermann, Daniel; Gordon, Jeffrey M.

2008-08-01

In the design of high-temperature chemical reactors and furnaces, as well as high-radiance light projection applications, reconstituting the ultra-high radiance of short-arc discharge lamps at maximum radiative efficiency constitutes a significant challenge. The difficulty is exacerbated by the high numerical aperture necessary at both the source and the target. Separating the optic from both the light source and the target allows practical operation, control, monitoring, diagnostics and maintenance. We present near-field unfolded aplanatic optics as a feasible solution. The concept is illustrated with a design customized to a high-temperature chemical reactor for nano-material synthesis, driven by an ultra-bright xenon short-arc discharge lamp, with near-unity numerical aperture for both light input and light output. We report preliminary optical measurements for the first prototype, which constitutes a double-ellipsoid solution. We also propose compound unfolded aplanats that collect the full angular extent of lamp emission (in lieu of light recycling optics) and additionally permit nearly full-circumference irradiation of the reactor.

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 is created either through flowing gas around the high voltage electrode in the discharge tube or self-generated by the plasma as in the steam discharge. This second method allows for large scale processing of contaminated water and for bulk chemical and optical analysis. Breakdown mechanisms of attached and unattached gas bubbles in liquid water were investigated using the first device. The breakdown scaling relation between breakdown voltage, pressure and dimensions of the discharge was studied. A Paschen-like voltage dependence for air bubbles in liquid water was discovered. The results of high-speed photography suggest the physical charging of the bubble due to a high voltage pulse; this charging can be significant enough to produce rapid kinetic motion of the bubble about the electrode region as the applied electric field changes over a voltage pulse. Physical deformation of the bubble is observed. This charging can also prevent breakdown from occurring, necessitating higher applied voltages to overcome the phenomenon. This dissertation also examines the resulting chemistry from plasma interacting with the bubble-liquid system. Through the use of optical emission spectroscopy, plasma parameters such as electron density, gas temperature, and molecular species production and intensity are found to have a time-dependence over the ac voltage cycle. This dependence is also source gas type dependent. These dependencies afford effective control over plasma-driven decomposition. The effect of plasma-produced radicals on various wastewater simulants is studied. Various organic dyes, halogenated compounds, and algae water are decomposed and assessed. Toxicology studies with melanoma cells exposed to plasma-treated dye solutions are completed, demonstrating the non-cytotoxic quality of the decomposition process. Thirdly, this dissertation examines the steam plasma system, developed through this research to circumvent the acidification associated with gas-feed discharges. This steam plasma creates its own gas pocket via field emission. This steam plasma is shown to have strong decontamination properties, with residual effects lasting beyond two weeks that continue to decompose contaminants. Finally, a "two-dimensional bubble" was developed and demonstrated as a novel diagnostic device to study the gas-water interface, the reaction zone. This device is shown to provide convenient access to the reaction zone and decomposition of various wastewater simulants is investigated.

Optical Characteristics of a Gas Discharge Plasma Based on a Mixture of Mercury Diiodide Vapor, Nitrogen, and Helium

NASA Astrophysics Data System (ADS)

Malinina, A. A.; Malinin, A. N.

2016-09-01

The results of studies of spectral, temporal, and energy characteristics of radiation in a gas discharge plasma based on a mixture of mercury diiodide vapor with helium and nitrogen in the spectral range of 350-800 nm are presented. Plasma was produced by a barrier discharge in a device with a cylindrical aperture. The electrodes 0.2 m in length were placed at a distance of 0.015 m. The amplitude of the pump pulses, their duration, and frequency were equal to 20-30 kV, 150 ns, and 1-20 kHz, respectively. Radiation of mercury monoiodide exciplex molecules was revealed in the visible spectra region. Dependences of the plasma optical characteristics on the partial pressures of the mixture components were established.

A survey of ELF and VLF research on lightning-ionosphere interactions and causative discharges

NASA Astrophysics Data System (ADS)

Inan, U. S.; Cummer, S. A.; Marshall, R. A.

2010-06-01

Extremely low frequency (ELF) and very low frequency (VLF) observations have formed the cornerstone of measurement and interpretation of effects of lightning discharges on the overlying upper atmospheric regions, as well as near-Earth space. ELF (0.3-3 kHz) and VLF (3-30 kHz) wave energy released by lightning discharges is often the agent of modification of the lower ionospheric medium that results in the conductivity changes and the excitation of optical emissions that constitute transient luminous events (TLEs). In addition, the resultant ionospheric changes are best (and often uniquely) observable as perturbations of subionospherically propagating VLF signals. In fact, some of the earliest evidence for direct disturbances of the lower ionosphere in association with lightning discharges was obtained in the course of the study of such VLF perturbations. Measurements of the detailed ELF and VLF waveforms of parent lightning discharges that produce TLEs and terrestrial gamma ray flashes (TGFs) have also been very fruitful, often revealing properties of such discharges that maximize ionospheric effects, such as generation of intense electromagnetic pulses (EMPs) or removal of large quantities of charge. In this paper, we provide a review of the development of ELF and VLF measurements, both from a historical point of view and from the point of view of their relationship to optical and other observations of ionospheric effects of lightning discharges.

Current Density Measurements of an Annular-Geometry Ion Engine

NASA Technical Reports Server (NTRS)

Shastry, Rohit; Patterson, Michael J.; Herman, Daniel A.; Foster, John E.

2012-01-01

The concept of the annular-geometry ion engine, or AGI-Engine, has been shown to have many potential benefits when scaling electric propulsion technologies to higher power. However, the necessary asymmetric location of the discharge cathode away from thruster centerline could potentially lead to non-uniformities in the discharge not present in conventional geometry ion thrusters. In an effort to characterize the degree of this potential nonuniformity, a number of current density measurements were taken on a breadboard AGI-Engine. Fourteen button probes were used to measure the ion current density of the discharge along a perforated electrode that replaced the ion optics during conditions of simulated beam extraction. Three Faraday probes spaced apart in the vertical direction were also used in a separate test to interrogate the plume of the AGI-Engine during true beam extraction. It was determined that both the discharge and the plume of the AGI-Engine are highly uniform, with variations under most conditions limited to 10% of the average current density in the discharge and 5% of the average current density in the plume. Beam flatness parameter measured 30 mm from the ion optics ranged from 0.85 0.95, and overall uniformity was shown to generally increase with increasing discharge and beam currents. These measurements indicate that the plasma is highly uniform despite the asymmetric location of the discharge cathode.

Current Density Measurements of an Annular-Geometry Ion Engine

NASA Technical Reports Server (NTRS)

Shastry, Rohit; Patterson, Michael J.; Herman, Daniel A.; Foster, John E.

2012-01-01

The concept of the annular-geometry ion engine, or AGI-Engine, has been shown to have many potential benefits when scaling electric propulsion technologies to higher power. However, the necessary asymmetric location of the discharge cathode away from thruster centerline could potentially lead to non-uniformities in the discharge not present in conventional geometry ion thrusters. In an effort to characterize the degree of this potential non-uniformity, a number of current density measurements were taken on a breadboard AGI-Engine. Fourteen button probes were used to measure the ion current density of the discharge along a perforated electrode that replaced the ion optics during conditions of simulated beam extraction. Three Faraday probes spaced apart in the vertical direction were also used in a separate test to interrogate the plume of the AGI-Engine during true beam extraction. It was determined that both the discharge and the plume of the AGI-Engine are highly uniform, with variations under most conditions limited to +/-10% of the average current density in the discharge and +/-5% of the average current density in the plume. Beam flatness parameter measured 30 mm from the ion optics ranged from 0.85 - 0.95, and overall uniformity was shown to generally increase with increasing discharge and beam currents. These measurements indicate that the plasma is highly uniform despite the asymmetric location of the discharge cathode.

Discharge prescribing of enteral opioids after initiation as a weaning strategy from continuous opioid infusions in the Intensive Care Unit.

PubMed

Kram, Bridgette; Weigel, Kylie M; Kuhrt, Michelle; Gilstrap, Daniel L

To evaluate the proportion of patients receiving a hospital discharge prescription for a scheduled enteral opioid following initiation as a weaning strategy from a continuous opioid infusion in the Intensive Care Unit (ICU). Retrospective, observational study. Five adult ICUs at a large, quaternary care academic medical center. Endotracheally intubated, opioid-naive adults receiving a continuous opioid infusion with a concomitant scheduled enteral opioid initiated. Exclusion criteria were receipt of fewer than two enteral opioid doses, documentation of a long-acting opioid as a home medication, the indication for the enteral opioid was not a weaning strategy, death during hospital admission or discharge to hospice. None. The proportion of ICU and hospital survivors who received a discharge prescription for a scheduled enteral opioid, total duration of continuous opioid infusion, duration of continuous opioid infusion after initiation of an enteral opioid therapy, total duration of enteral therapy, ICU and hospital length of stay. Of 62 included patients, 19 patients (30.6 percent) received a new prescription for a scheduled enteral opioid at hospital discharge. The median duration of enteral opioid therapy was longer for patients who received a discharge prescription compared to those who did not (20.09 vs 8.89 days, p = 0.02), though the remaining endpoints were not different. Utilizing scheduled enteral opioids as a weaning strategy from continuous opioid infusions may place patients at risk of ICU-acquired physical dependence on opioids.

Plasma channel optical pumping device and method

DOEpatents

Judd, O.P.

1983-06-28

A device and method are disclosed for optically pumping a gaseous laser using blackbody radiation produced by a plasma channel which is formed from an electrical discharge between two electrodes spaced at opposite longitudinal ends of the laser. A preionization device which can comprise a laser or electron beam accelerator produces a preionization beam which is sufficient to cause an electrical discharge between the electrodes to initiate the plasma channel along the preionization path. The optical pumping energy is supplied by a high voltage power supply rather than by the preionization beam. High output optical intensities are produced by the laser due to the high temperature blackbody radiation produced by the plasma channel, in the same manner as an exploding wire type laser. However, unlike the exploding wire type laser, the disclosed invention can be operated in a repetitive manner by utilizing a repetitive pulsed preionization device. 5 figs.

Two-wavelength quadrature multipoint detection of partial discharge in power transformers using fiber Fabry-Perot acoustic sensors

NASA Astrophysics Data System (ADS)

Dong, Bo; Han, Ming; Wang, Anbo

2012-06-01

A reliable and low-cost two-wavelength quadrature interrogating method has been developed to demodulate optical signals from diaphragm-based Fabry-Perot interferometric fiber optic sensors for multipoint partial discharge detection in power transformers. Commercial available fused-silica parts (a wafer, a fiber ferrule, and a mating sleeve) and a cleaved optical single mode fiber were bonded together to form an extrinsic Fabry-Perot acoustic sensor. Two lasers with center wavelengths separated by a quarter of the period of sensor interference fringes were used to probe acousticwave- induced diaphragm vibration. A coarse wavelength-division multiplexing (CWDM) add/drop multiplexer was used to separate the reflected two wavelengths before two photo detectors. Optical couplers were used to distribute mixed laser light to each sensor-detector module for multiplexing purpose. Sensor structure, detection system design and experiment results are presented.

Continuous tonic spike activity in spider warm cells in the absence of sensory input.

PubMed

Gingl, E; Tichy, H

2006-09-01

The warm cells of the spider tarsal organ respond very sensitively to low-amplitude changes in temperature and discharge continuously as the rate of change in temperature reaches zero. To test whether the continuous tonic discharge remains without sensory input, we blocked the warm cell's receptive region by Epoxy glue. The activity continued in this situation, but its dependence on temperature changes was strongly reduced. We interpret this to mean that the warm cells exhibit specific intrinsic properties that underlie the generation of the tonic discharge. Experiments with electrical stimulation confirmed the observation that the warm cells persist in activity without an external drive. In warm cells with blocked receptive region, the response curves describing the relationship between the tonic discharge and the level of depolarization is the same for different temperatures. In warm cells with intact receptive region, the curves are shifted upward with rising temperature, as if the injected current is simply added to the receptor current. This indicates a modulating effect of the receptor current on the tonic discharge. Stimulation causes a change in the tonic discharge rate and thereby enables individual warm cells to signal the direction in addition to the magnitude of temperature changes.

Spectroscopic diagnosis of plasma in atmospheric pressure negative pulsed gas-liquid discharge with nozzle-cylinder electrode

NASA Astrophysics Data System (ADS)

Ming, SUN; Zhan, TAO; Zhipeng, ZHU; Dong, WANG; Wenjun, PAN

2018-05-01

The plasma characteristics of a gas-liquid phase discharge reactor were investigated by optical and electrical methods. The nozzle-cylinder electrode in the discharge reactor was supplied with a negative nanosecond pulsed generator. The optical emission spectrum diagnosis revealed that OH (A2∑+ → X2Π, 306–309 nm), N2 (C3Π→B3Πg, 337 nm), O (3p5p→3s5s0, 777.2 nm) and O (3p3p→3s3s0, 844.6 nm) were produced in the discharge plasma channels. The electron temperature (T e) was calculated from the emission relative intensity ratio between the atomic O 777.2 nm and 844.6 nm, and it increased with the applied voltage and the pulsed frequency and fell within the range of 0.5–0.8 eV. The gas temperature (T g) that was measured by Lifbase was in a range from 400 K to 600 K.

Excimer lasers

NASA Technical Reports Server (NTRS)

Palmer, A. J.; Hess, L. D.; Stephens, R. R.; Pepper, D. M.

1977-01-01

The results of a two-year investigation into the possibility of developing continuous wave excimer lasers are reported. The program included the evaluation and selection of candidate molecular systems and discharge pumping techniques. The K Ar/K2 excimer dimer molecules and the xenon fluoride excimer molecule were selected for study; each used a transverse and capillary discharges pumping technique. Experimental and theoretical studies of each of the two discharge techniques applied to each of the two molecular systems are reported. Discharge stability and fluorine consumption were found to be the principle impediments to extending the XeF excimer laser into the continuous wave regime. Potassium vapor handling problems were the principal difficulty in achieving laser action on the K Ar/K2 system. Of the four molecular systems and pumping techniques explored, the capillary discharge pumped K Ar/K2 system appears to be the most likely candidate for demonstrating continuous wave excimer laser action primarily because of its predicted lower pumping threshold and a demonstrated discharge stability advantage.

A broadband LED source in visible to short-wave-infrared wavelengths for spectral tumor diagnostics

NASA Astrophysics Data System (ADS)

Hayashi, Daiyu; van Dongen, Anne Marie; Boerekamp, Jack; Spoor, Sandra; Lucassen, Gerald; Schleipen, Jean

2017-06-01

Various tumor types exhibit the spectral fingerprints in the absorption and reflection spectra in visible and especially in near- to short-wave-infrared wavelength ranges. For the purpose of spectral tumor diagnostics by means of diffuse reflectance spectroscopy, we developed a broadband light emitting diode (LED) source consisting of a blue LED for optical excitation, Lu3Al5O12:Ce3+,Cr3+ luminescent garnet for visible to near infrared emissions, and Bismuth doped GeO2 luminescent glass for near-infrared to short-wave infrared emissions. It emits broad-band light emissions continuously in 470-1600 nm with a spectral gap at 900-1000 nm. In comparison to the currently available broadband light sources like halogen lamps, high-pressure discharge lamps and super continuum lasers, the light sources of this paper has significant advantages for spectral tissue diagnostics in high-spectral stability, improved light coupling to optical fibers, potential in low light source cost and enabling battery-drive.

Diagnostic of capacitively coupled radio frequency plasma from electrical discharge characteristics: comparison with optical emission spectroscopy and fluid model simulation

NASA Astrophysics Data System (ADS)

Xiang, HE; Chong, LIU; Yachun, ZHANG; Jianping, CHEN; Yudong, CHEN; Xiaojun, ZENG; Bingyan, CHEN; Jiaxin, PANG; Yibing, WANG

2018-02-01

The capacitively coupled radio frequency (CCRF) plasma has been widely used in various fields. In some cases, it requires us to estimate the range of key plasma parameters simpler and quicker in order to understand the behavior in plasma. In this paper, a glass vacuum chamber and a pair of plate electrodes were designed and fabricated, using 13.56 MHz radio frequency (RF) discharge technology to ionize the working gas of Ar. This discharge was mathematically described with equivalent circuit model. The discharge voltage and current of the plasma were measured at different pressures and different powers. Based on the capacitively coupled homogeneous discharge model, the equivalent circuit and the analytical formula were established. The plasma density and temperature were calculated by using the equivalent impedance principle and energy balance equation. The experimental results show that when RF discharge power is 50-300 W and pressure is 25-250 Pa, the average electron temperature is about 1.7-2.1 eV and the average electron density is about 0.5 × 1017-3.6 × 1017 m-3. Agreement was found when the results were compared to those given by optical emission spectroscopy and COMSOL simulation.

Identifying Stream/Aquifer Exchange by Temperature Gradient in a Guarani Aquifer System Outcrop Zone

NASA Astrophysics Data System (ADS)

Wendland, E.; Rosa, D. M. S.; Anache, J. A. A.; Lowry, C.; Lin, Y. F. F.

2017-12-01

Recharge of the Guarani Aquifer System (GAS) in South America is supposed to occur mainly in the outcrop zones, where the GAS appears as an unconfined aquifer (10% of the 1.2 Million km2 aquifer extension). Previous evaluations of recharge are based essentially on water balance estimates for the whole aquifer area or water table fluctuations in monitoring wells. To gain a more detailed understanding of the recharge mechanisms the present work aimed to study the stream aquifer interaction in a watershed (Ribeirão da Onça) at an outcrop zone. Two Parshall flumes were installed 1.3 km apart for discharge measurement in the stream. Along this distance an optic fiber cable was deployed to identify stretches with gaining and losing behavior. In order to estimate groundwater discharge in specific locations, 8 temperature sticks were set up along the stream reach to measure continuously the vertical temperature gradient. A temperature probe with 4 thermistors was also used to map the shallow streambed temperature gradient manually along the whole distance. The obtained results show a discharge difference of 250 m3/h between both flumes. Since the last significant rainfall (15 mm) in the watershed occurred 3 months ago, this value can be interpreted as the base flow contribution to the stream during the dry season. Given the temperature difference between groundwater ( 24oC) and surface water ( 17oC) the fiber-optic distributed temperature sensing (FO-DTS) allowed the identification of stretches with gaining behavior. Temperature gradients observed at the streambed varied between 0.67 and 14.33 oC/m. The study demonstrated that heat may be used as natural tracer even in tropical conditions, where the groundwater temperature is higher than the surface water temperature during the winter. The obtained results show that the discharge difference between both flumes can not be extrapolated without detailed analysis. Gaining and loosing stretches have to be identified on order to estimate total base flow contribution of the watershed. This result is important to correct the water balance of the system.

Developing a diagnostic tool for measuring maximum effective temperature within high pressure electrodeless discharges

NASA Astrophysics Data System (ADS)

Whiting, Michael; Preston, Barry; Mucklejohn, Stuart; Santos, Monica; Lister, Graeme

2016-09-01

Here we present an investigation into the feasibility of creating a diagnostic tool for obtaining maximum arc temperature measurements within a high pressure electrodeless discharge; utilizing integrating sphere measurements of optically thin lines emitted from mercury atoms within commercially available high pressure mercury lamp arc tubes. The optically thin lines chosen were 577 nm and 1014 nm from a 250 W high pressure mercury lamp operated at various powers. The effective temperature could be calculated by considering the relative intensities of the two optically thin lines and comparison with the theoretical ratio of the temperature dependent power emitted from the lines derived from the atomic spectral data provided by NIST. The calculations gave effective arc temperatures of 5755, 5804 and 5820 K at 200, 225, 250 W respectively. This method was subsequently used as a basis for determining maximum effective arc temperature within microwave-driven electrodeless discharge capsules, with varying mercury content of 6.07, 9.4 and 12.95 mg within 1 × 10-6 m3 giving maximum effective temperatures of 5163, 4768 and 4715 K respectively at 240 W.

Halting the fuse discharge propagation using optical fiber microwires.

PubMed

Rocha, A M; Fernandes, G; Domingues, F; Niehus, M; Pinto, A N; Facão, M; André, P S

2012-09-10

We report and analyze the halting of the fuse effect propagation in optical fiber microwires. The increase of the mode field diameter in the tapered region decreases the optical intensity resulting in the extinction of the fuse effect. This fiber element presents a low insertion loss and can be introduced in the optical network in order to protect the active equipment from the damage caused by the fuse effect.

Electron-impact ionization and electron attachment cross sections of radicals important in transient gaseous discharges

NASA Technical Reports Server (NTRS)

Lee, Long C.; Srivastava, Santosh K.

1990-01-01

Electron-impact ionization and electron attachment cross sections of radicals and excited molecules were measured using an apparatus that consists of an electron beam, a molecular beam and a laser beam. The information obtained is needed for the pulse power applications in the areas of high power gaseous discharge switches, high energy lasers, particle beam experiments, and electromagnetic pulse systems. The basic data needed for the development of optically-controlled discharge switches were also investigated. Transient current pulses induced by laser irradiation of discharge media were observed and applied for the study of electron-molecule reaction kinetics in gaseous discharges.

Optical magnetic resonances induced by the interference of reactive components in the near radiation-field zone of atoms in a glow discharge of a mixture of even neon isotopes

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

Saprykin, E. G., E-mail: Saprykin@gorodok.net

2016-02-15

Four types of anomalous optical magnetic resonances shifted with respect to the zero magnetic field and with different shapes are found in radiation of a glow discharge in a mixture of even neon isotopes placed in a swept longitudinal magnetic field. This testifies to the manifestation of collective processes of synchronous light emission by oscillators belonging to isotopically different spatially separated atoms in discharge plasma. The origin of resonances is associated with nonstationary interference of reactive fields in the near radiation-field zones of emission of atoms, averaged over the lifetime of the fields (interference), while different types of resonances aremore » associated with different methods of synchronization of the phases of the fields.« less

Fabrication of optical fiber sensor based on double-layer SU-8 diaphragm and the partial discharge detection

NASA Astrophysics Data System (ADS)

Shang, Ya-na; Ni, Qing-yan; Ding, Ding; Chen, Na; Wang, Ting-yun

2015-01-01

In this paper, a partial discharge detection system is proposed using an optical fiber Fabry-Perot (FP) interferometric sensor, which is fabricated by photolithography. SU-8 photoresist is employed due to its low Young's modulus and potentially high sensitivity for ultrasound detection. The FP cavity is formed by coating the fiber end face with two layers of SU-8 so that the cavity can be controlled by the thickness of the middle layer of SU-8. Static pressure measurement experiments are done to estimate the sensing performance. The results show that the SU-8 based sensor has a sensitivity of 154.8 nm/kPa, which is much higher than that of silica based sensor under the same condition. Moreover, the sensor is demonstrated successfully to detect ultrasound from electrode discharge.

Fiber Fabry-Perot sensors for detection of partial discharges in power transformers.

PubMed

Yu, Bing; Kim, Dae Woong; Deng, Jiangdong; Xiao, Hai; Wang, Anbo

2003-06-01

A diaphragm-based interferometric fiberoptic sensor that uses a low-coherence light source was designed and tested for on-line detection of the acoustic waves generated by partial discharges inside high-voltage power transformers. The sensor uses a fused-silica diaphragm and a single-mode optical fiber encapsulated in a fused-silica glass tube to form an extrinsic Fabry-Perot interferometer, which is interrogated by low-coherence light. Test results indicate that these fiber optic acoustic sensors are capable of faithfully detecting acoustic signals propagating inside transformer oil with high sensitivity and wide bandwidth.

Optical properties of hydrogenated amorphous carbon films grown from methane plasma

NASA Technical Reports Server (NTRS)

Pouch, J. J.; Alterovitz, S. A.; Warner, J. D.; Liu, D. C.; Lanford, W. A.

1985-01-01

A 30 kHz ac glow discharge formed from methane gas was used to grow carbon films on InP substrates. Both the growth rate, and the realitive Ar ion sputtering rate at 3 keV varied monotonically with deposition power. Results from the N-15 nuclear reaction profile experiments indicated a slight drop in the hydrogen concentration as more energy was dissipated in the ac discharge. Values for the index of refraction and extinction coefficient ranged from 1.721 to 1.910 and 0 to -0.188, respectively. Optical bandgaps as high as 2.34 eV were determined.

Optical fiber sensor of partial discharges in High Voltage DC experiments

NASA Astrophysics Data System (ADS)

Búa-Núñez, I.; Azcárraga-Ramos, C. G.; Posada-Román, J. E.; Garcia-Souto, J. A.

2014-05-01

A setup simulating High Voltage DC (HVDC) transformers barriers was developed to demonstrate the effectiveness of an optical fiber (OF) sensor in detecting partial discharges (PD) under these peculiar conditions. Different PD detection techniques were compared: electrical methods, and acoustic methods. Standard piezoelectric sensors (R15i-AST) and the above mentioned OF sensors were used for acoustic detection. The OF sensor was able to detect PD acoustically with a sensitivity better than the other detection methods. The multichannel instrumentation system was tested in real HVDC conditions with the aim of analyzing the behavior of the insulation (mineral oil/pressboard).

Modeling of Optical Waveguide Poling and Thermally Stimulated Discharge (TSD) Charge and Current Densities for Guest/Host Electro Optic Polymers

NASA Technical Reports Server (NTRS)

Watson, Michael D.; Ashley, Paul R.; Abushagur, Mustafa

2004-01-01

A charge density and current density model of a waveguide system has been developed to explore the effects of electric field electrode poling. An optical waveguide may be modeled during poling by considering the dielectric charge distribution, polarization charge distribution, and conduction charge generated by the poling field. These charge distributions are the source of poling current densities. The model shows that boundary charge current density and polarization current density are the major source of currents measured during poling and thermally stimulated discharge These charge distributions provide insight into the poling mechanisms and are directly related to E(sub A), and, alpha(sub r). Initial comparisons with experimental data show excellent correlation to the model results.

Application of ICP-OES for Evaluating Energy Extraction and Production Wastewater Discharge Impacts on Surface Waters in Western Pennsylvania

EPA Science Inventory

Oil and gas extraction and coal-fired electrical power generating stations produce wastewaters that are treated and discharged to rivers in Western Pennsylvania with public drinking water system (PDWS) intakes. Inductively coupled plasma optical emission spectroscopy (ICP-OES) w...

Optical alignment of electrodes on electrical discharge machines

NASA Technical Reports Server (NTRS)

Boissevain, A. G.; Nelson, B. W.

1972-01-01

Shadowgraph system projects magnified image on screen so that alignment of small electrodes mounted on electrical discharge machines can be corrected and verified. Technique may be adapted to other machine tool equipment where physical contact cannot be made during inspection and access to tool limits conventional runout checking procedures.

Photometric Characteristics of Sprites and Elves Derived from JEM-GLIMS Nadir Observations (Invited)

NASA Astrophysics Data System (ADS)

Sato, M.; Takahashi, Y.; Adachi, T.; Kobayashi, N.; Mihara, M.; Ushio, T.; Morimoto, T.; Suzuki, M.; Yamazaki, A.; Inan, U.; Linscott, I.

2013-12-01

The main goal of the JEM-GLIMS mission is to identify the horizontal structures of Transient Luminous Events (TLEs) and spatiotemporal relationship between TLEs and their parent lightning discharges based on the nadir observations from the International Space Station (ISS). For this purpose JEM-GLIMS equips two sets of optical instruments (LSI: CMOS camera, and PH: spectrophotometers) and two sets of radio wave receivers (VLFR: VLF receiver, and VITF: VHF interferometer). As all these instruments are installed at the bottom plane of the bus module facing to the Earth, JEM-GLIMS can carry out the nadir observations continuously. JEM-GLIMS was launched by HTV3 and was successfully installed at the exposed facility of the Japanese Experiment Module (JEM) on August 9, 2012. After the initial checkout operations, JEM-GLIMS finally started continuous observations on November 20, 2012. In the period from November 20, 2012 to June 30, 2013, totally 1597 transient optical events related to lightning flashes and/or TLE emissions were detected by the optical instruments. In 578 of these events, both LSI and PH detected clear transient optical signals well above the noise level. In order to derive sprite events from the detected transient optical events, we analyzed PH light-curve data first and estimated the peak irradiance related to the transient optical flashes. Then, we compared these intensities with the atmospheric transmittance. Finally, LSI image data are examined to clarify the morphological properties of the optical emission. We analyzed a transient optical event detected at 00:56:29.198 UT on December 15, 2012. The peak intensities of PH channels are estimated to be 1.4E-2 W/m2 (150-280 nm), 2.3E-4 W/m2 (316 nm), 5.9E-4 W/m2 (337 nm), 4.0E-4 W/m2 (392 nm), 4.2E-4 W/m2 (762 nm), and 6.3E-2 W/m2 (600-900 nm), respectively. It is found that all these intensities are significantly stronger than the lightning emission affected by the atmospheric transmittance. This fact implies that the light sources exist not only in the troposphere but also in the mesosphere. At the image data obtained by the narrow-band filter camera (LSI-2), a pancake structure with bright spots was confirmed. Thus, we attributed the pancake structure and bright spots to a sprite halo and sprite streamers, respectively. We further analyzed a transient optical event obtained at 01:41:00.466 UT on March 30, 2013. In this event very strong pulse signals are detected only by PH1 (150-280 nm) and PH4 (600-900 nm). Since the field-of-view (FOV) of PH4 is 86.8 deg., which is larger than that of other PH channels (FOV=42.7 deg.), a lightning discharge seems to be occurred within PH4 FOV but without FOV of the other PH channels. Nevertheless, the existence of the strong FUV emission detected by PH1 means the occurrence of elves. At the presentation, we will show the results derived from LSI and PH data analysis and will discuss the photometric characteristics more in detail.

The impact of discharge plan upon re-admission, satisfaction with nursing care and the ability to self-care for coronary artery bypass graft surgery patients.

PubMed

Negarandeh, Reza; Nayeri, Nahid Dehghan; Shirani, Farimah; Janani, Leila

2012-12-01

Grafting coronary arteries and post operative recovery has many challenges, which can be ameliorated through continues care and an appropriate discharge plan. Therefore, the current study was undertaken aiming to evaluate the impact of discharge plan on satisfaction with nursing care, ability to self-care, and incidence of re-admission. This is a quasi experimental study involving patients who were due to undergo coronary artery bypass graft in Chamran Hospital in 2010. In the intervention group, the discharge plan was initiated at the time of admission and continued for 2 weeks after discharge by home visit and telephone follow ups. Satisfaction with nursing care was assessed 2 days after discharge, whilst patients' ability for self-care was measured 6 weeks and 3 months post discharge and the incidence of re-admission was determined at the 3 months point. Satisfaction levels with nursing care and the ability to take self-care were higher in intervention group comparing with control group (p < 0.001). There was a significant difference for self-care ability between pre test and post test in both groups but the improvement was more pronounced for the intervention group (p = 0.04). There was no significant difference between the two groups in terms of re-admission incidence after 3 months (p = 0.15). The results indicate that the discharge plan, as a method of continual care plan, can lead to higher satisfaction levels and enhanced self-care abilities of patients. Such discharge plan can therefore be utilised as an effective method of continuous care for patients who are going to undergo coronary artery bypass graft.

Intense laser pulse propagation in capillary discharge plasma channels

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

Hubbard, R. F.; Moore, C. I.; Sprangle, P.

Optical guiding of intense laser pulses is required for plasma-based accelerator concepts such as the laser wakefield accelerator. Reported experiments have successfully transported intense laser pulses in the hollow plasma column produced by a capillary discharge. The hollow plasma has an index of refraction which peaks on-axis, thus providing optical guiding which overcomes beam expansion due to diffraction. In more recent experiments at Hebrew University, 800 nm wavelength, 0.1 mJ, 100 fs pulses have been guided in {approx}300 micron radius capillaries over distances as long as 6.6 cm. Simulations of these experiments using a 2-D nonlinear laser propagation model producemore » the expected optical guiding, with the laser pulse radius r{sub L} exhibiting oscillations about the equilibrium value predicted by an analytical envelope equation model. The oscillations are damped at the front of the pulse and grow in amplitude in the back of the pulse. This growth and damping is attributed to finite pulse length effects. Simulations also show that further ionization of the discharge plasma by the laser pulse may hollow the laser pulse and introduce modulations in the spot size. This ionization-defocusing effect is expected to be significant at the high intensities required for accelerator application. Capillary discharge experiments at much higher intensities are in progress on the Naval Research Laboratory T{sup 3} laser, and preliminary results are reported.« less

Systematic investigation of the barrier discharge operation in helium, nitrogen, and mixtures: discharge development, formation and decay of surface charges

NASA Astrophysics Data System (ADS)

Tschiersch, R.; Bogaczyk, M.; Wagner, H.-E.

2014-09-01

As a logical extension to previous investigations of the barrier discharge (BD) in helium and nitrogen, the present work reports on the operation in any mixtures of both pure gases. Using a well-established plane-parallel discharge cell configuration allows to study the influence of the He/N2 mixing ratio on the formation of different discharge modes. Their characterization was made by measuring the discharge emission development together with the formation and decay of surface charges on a bismuth silicon oxide (Bi12SiO20, BSO) crystal. This was realized by the simultaneous application of the spatio-temporally resolved optical emission spectroscopy, and the electro-optic Pockels effect in combination with a CCD high speed camera. The existence diagram for diffuse and filamentary BDs was determined by varying the amplitude and shape of the applied voltage. Over the entire range of the He/N2 ratio, the diffuse mode can be operated at moderate voltage amplitudes whereas filamentation occurs at significant overvoltage and is favoured by a high voltage slew rate. Irrespective of the discharge mode, the overall charge transfer during a discharge breakdown is found to be in excellent agreement with the amount of accumulated surface charges. An exponential decay of the surface charge deposited on the BSO crystal is induced by LED illumination beyond a typical discharge cycle. During the decay process, a broadening of the radial profiles of positive as well as negative surface charge spots originating from previous microdischarges is observed. The investigations contribute to a better understanding of the charge accumulation at a dielectric.

Optical state-of-charge monitor for batteries

DOEpatents

Weiss, Jonathan D.

1999-01-01

A method and apparatus for determining the instantaneous state-of-charge of a battery in which change in composition with discharge manifests itself as a change in optical absorption. In a lead-acid battery, the sensor comprises a fiber optic system with an absorption cell or, alternatively, an optical fiber woven into an absorbed-glass-mat battery. In a lithium-ion battery, the sensor comprises fiber optics for introducing light into the anode to monitor absorption when lithium ions are introduced.

32 CFR 724.810 - Availability of Naval Discharge Review Board documents for public inspection and copying.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Availability of Naval Discharge Review Board... (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Procedures of Naval Discharge Review Board § 724.810 Availability of Naval Discharge Review Board documents for public inspection and...

32 CFR 724.810 - Availability of Naval Discharge Review Board documents for public inspection and copying.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Availability of Naval Discharge Review Board... (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Procedures of Naval Discharge Review Board § 724.810 Availability of Naval Discharge Review Board documents for public inspection and...

In Situ Stoichiometry in a Large River: Continuous Measurement of Doc, NO3 and PO4 in the Sacramento River

NASA Astrophysics Data System (ADS)

Downing, B. D.; Pellerin, B. A.; Bergamaschi, B. A.; Saraceno, J.

2011-12-01

Studying controls on geochemical processes in rivers and streams is difficult because concentration and composition often changes rapidly in response to physical and biological forcings. Understanding biogeochemical dynamics in rivers will improve current understanding of the role of watershed sources to carbon cycling, river and stream ecology, and loads to estuaries and oceans. Continuous measurements of dissolved organic carbon (DOC), nitrate (NO3-) and soluble reactive phosphate (SRP) concentrations are now possible, along with some information about DOC composition. In situ sensors designed to measure these constituents provide high frequency, real-time data that can elucidate hydrologic and biogeochemical controls which are difficult to detect using more traditional sampling approaches. Here we present a coupled approach, using in situ optical instrumentation with discharge measurements to provide quantitative estimates of constituent loads to investigate C, NO3- and SRP sources and processing in the Sacramento River, CA, USA. Continuous measurement of DOC concentration was conducted by use of a miniature in situ fluorometer (Turner Designs Cyclops) designed to measure chromophoric dissolved organic matter fluorescence (FDOM) over the course of an entire year. Nitrate was measured concurrently using a Satlantic SUNA and phosphate was measured using a WETLabs model Cycle-P instrument for a two week period in July 2011. Continuous measurement from these instruments paired with continuous measurement of physical water quality variables such as temperature, pH, specific conductance, dissolved oxygen, and turbidity, were used to investigate physical and chemical dynamics of DOC, NO3-, SRP over varying time scales. Deploying these instruments at pre-existing USGS discharge gages allowed for calculation of instantaneous and integrated constituent fluxes, as well as filling in gaps in our understanding biogeochemical processes and transport. Results from the study show that diurnal, event driven and seasonal changes are key to calculating accurate watershed fluxes and detecting transient sources of DOC, NO3- and SRP.

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

Mendoza-Lopez, M.L.; Centro de Fisica Aplicada y Tecnologia Avanzada, Departamento de Nanotecnologia, Universidad Nacional Autonoma de Mexico, Campus Juriquilla, Apdo. Postal 1-1010, Queretaro Qro. C.P. 76230; Perez-Bueno, J.J.

This paper presents a complete methodology for the characterization of silver alloys used in modern coin production. Mexican coins with a nominal silver concentration from 10% to 99.99% were used in this study. Calibrated Glow Discharge Optical Emission Spectrometers were used to determine the chemical composition of the alloys as a function of the depth, while inductively coupled plasma was used to determine the total element composition in bulk. Scanning Electron Microscope was used to study the phase distributions in the different silver coins. According to Glow Discharge Optical Emission Spectrometers and inductively coupled plasma, the silver content found inmore » the studied samples was consistently greater than that of the nominal silver content reported by the Mexican mint. This may lead to a review of the new methods of analysis used nowadays in contemporary coin minting. This result is very important because silver is increasing in value as metal and, considering the volume of production of silver coins, this may increase further as a consequence of a growing popular confidence in silver currency. In the case of silver studies, an advantage of the absence of silver detector in the Glow Discharge Optical Emission Spectrometers system is that it allows for the recalibration to have a better range of detection of other metals present in the alloys. A calibration curve using the copper content obtained by inductively coupled plasma (bulk) and Glow Discharge Optical Emission Spectrometers (depth profile) was performed. The relevance of control in modern silver coin minting was clarified, especially in minimizing the discrepancy between the nominal and the core fineness. The physical and chemical properties of the alloys studied are defined, revealing important variations in silver and copper contents. A new methodology and metrology for the control of coinage are suggested.« less

[A photo-optical observation of gallbladder motility in dogs (author's transl)].

PubMed

Kudo, N

1976-03-01

A photo-optical observation on gallbladder motility was made with the 16 mm cine-cholangiography. The subjects studied were thirty two mongrel dogs. The gallbladder was exposed by a short upper midline abdominal incision under pentothal anesthesia. Gallbladder bile was aspirated and contrast medium was given into the bladder, through a transhepatic route. The cine-cholangiography was done by an image intensifier at a speed of one frame every 2 to 4 seconds. The cinefilms taken were observed repeatedly by the screen projection at various speeds. The drawings were made by tracing the outline of the image of the gallbladder on each frame and were overlapped. Moreover, a contraction curve was made by the cholecystometry using of film motion analyzer in every case. At the same time bile flow into the duodenum was recorded to study a relationship between the gallbladder contraction and motility of the terminal common bile duct. The results obtained are as follows: 1. In a resting state any contraction of the gallbladder was not seen during 30 minutes, and a peristalsis-like movements of the neck portion was observed. However, there was not a relationship between the contraction curve of the gallbladder and the bile flow into the duodenum. 2. Immediately after giving Caerulein, the contrast medium injected into the gallbladder was rapidly discharged into the common bile duct by a peristalsis-like movement of the neck. The size of the gallbladder was markedly decreased into three fifths of the initial state three minutes after administration. At the same time contrast medium was continuously discharged into the duodenum. 3. After giving pilocarpine a marked contraction with forceful movement of the neck and body was observed, and the size of the gallbladder was decreased into three quarters ot the initial state. Bile discharge into the duodenum was markedly increased with an active open- and closing movement of the terminal common bile duct.

Full spatial-field visualization of gas temperature in an air micro-glow discharge by calibrated Schlieren photography

NASA Astrophysics Data System (ADS)

Xiong, Qing; Xu, Le; Wang, Xia; Xiong, Lin; Huang, Qinghua; Chen, Qiang; Wang, Jingang; Peng, Wenxiong; Li, Jiarui

2018-03-01

Gas temperature is an important basic parameter for both fundamental research and applications of plasmas. In this work, efforts were made to visualize the full spatial field of gas temperature (T g) in a microdischarge with sharp T g gradients by a method of calibrated Schlieren (CS) photography. Compared to other two typical diagnostic approaches, optical emission spectroscopy (OES) and Rayleigh scattering, the proposed CS method exhibits the ability to capture the whole field of gas temperature using a single Schlieren image, even the discharge is of non-luminous zones like Faraday dark space (FDS). The image shows that the T g field in the studied micro-glow air discharge expands quickly with the increase of discharge currents, especially in the cathode region. The two-dimensional maps of gas temperature display a ‘W-shape’ with sharp gradients in both areas of negative and positive glows, slightly arched distributions in the positive column, and cooling zones in the FDS. The obtained T g fields show similar patterns to that of the discharge luminance. With an increase in discharge currents, more electric energy is dissipated by heating air gas and inducing constriction of the low-temperature FDS. Except in the vicinities of electrode boundaries, due to the interference from optical diffraction, the estimated gas temperature distributions are of acceptable accuracy, confirmed by the approaches of OES and UV Rayleigh scattering.

Characteristics of Capacity Coupled Discharge in Atmospheric Pressure Air

NASA Astrophysics Data System (ADS)

Sasaki, Tadahiro; Omukai, Reina; Mukaigawa, Seiji; Takaki, Koichi; Fujiwara, Tamiya; Mase, Hiroshi; Sato, Noriyoshi

This paper describes characteristics of capacity coupled discharge in atmospheric pressure air with focusing influence of gap length of point-to-plane electrode configuration on input power into the discharge. The discharge can be quenched in short time duration by inserting a small capacitance capacitor between the electrode and the ground. We employed a needle electrode and a coaxial cable as the quenching capacitor. The discharge was successfully quenched within 25 ns in duration according to 9.4 pF in a capacitance of the quenching capacitor. The discharge was classified as two modes; a spark mode and a corona mode. At the spark mode, the power consumed in the discharge plasma was almost 10 times as large as that of a conventional dielectric barrier discharge. At the corona mode, the consumed energy was almost same value with that of the dielectric barrier discharge. A velocity of the discharge development was obtained to be 3×105 m/s by an optical measurement.

32 CFR 724.117 - Discharge review.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Discharge review. 724.117 Section 724.117 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.117 Discharge review. A nonadversary administrative reappraisal at the level of...

NOx formation in apokamp-type atmospheric pressure plasma jets in air initiated by a pulse-repetitive discharge

NASA Astrophysics Data System (ADS)

Sosnin, Eduard A.; Didenko, Maria V.; Panarin, Victor A.; Skakun, Victor S.; Tarasenko, Victor F.; Liu, Dongping P.; Song, Ying

2018-04-01

The decomposition products of atmospheric pressure plasma of repetitive pulsed discharge in apokamp and corona modes were determined by optical and chemical methods. It is shown, that the decomposition products contain mainly nitrogen oxides NOx. A brief review of the plasma- and thermochemical reactions in the pulsed discharges was made. The review and experimental data allow us to explain the reactive oxygen species formation mechanisms in a potential discharge channel with apokamp. The possible applications of this plasma source for treatment of seeds of agricultural crops are discussed.

Dynamics of the plasma current sheath in plasma focus discharges in different gases

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

Vinogradov, V. P.; Krauz, V. I., E-mail: krauz-vi@nrcki.ru; Mokeev, A. N.

2016-12-15

The shape of the plasma current sheath (PCS) in the final stage of its radial compression, the dynamics of pinching, and the subsequent pinch decay in plasma focus (PF) discharges in different gases are studied using an improved multichannel system of electron-optical plasma photography and a newly elaborated synchronization system. The PCS structure in discharges in heavy gases (Ne, Ar) is found to differ significantly from that in discharges in hydrogen and deuterium. The influence of a heavy gas (Xe) additive to hydrogen and deuterium on the structure and compression dynamics of the PCS is investigated.

Water Resources Data, Florida, Water Year 2003, Volume 3B: Southwest Florida Ground Water

USGS Publications Warehouse

Kane, Richard L.; Fletcher, William L.; Lane, Susan L.

2004-01-01

Water resources data for the 2003 water year in Florida consist of continuous or daily discharges for 385 streams, periodic discharge for 13 streams, continuous daily stage for 255 streams, periodic stage for 13 streams, peak stage for 36 streams and peak discharge for 36 streams, continuous or daily elevations for 13 lakes, periodic elevations for 46 lakes; continuous ground-water levels for 441 wells, periodic ground-water levels for 1,227 wells, and quality-of-water data for 133 surface-water sites and 308 wells. The data for Southwest Florida include records of stage, discharge, and water quality of streams; stage, contents, water quality of lakes and reservoirs, and water levels and water quality of ground-water wells. Volume 3B contains records for continuous ground-water elevations for 128 wells; periodic ground-water elevations at 31 wells; miscellaneous ground-water elevations at 405 wells; and water quality at 32 ground-water sites. These data represent the national Water Data System records collected by the U.S. Geological Survey and cooperating local, state, and federal agencies in Florida.

Chromophore Poling in Thin Films of Organic Glasses. 2. Two-Electrode Corona Discharge Setup

NASA Astrophysics Data System (ADS)

Vilitis, O.; Muzikante, I.; Rutkis, M.; Vembris, A.

2012-01-01

In Part 1 of the article we provided description of the corona discharge physics and overview of the methods used for corona poling in thin organic films. Subsequent sections describe comparatively simple technical methods for poling the organic nonlinear optical polymers using a two-electrode (point-to-plate or wire-to-plate) technique. The polarization build-up was studied by the DC positive corona method for poling the nonlinear optical (NLO) polymers. The experimental setup provides the corona discharge current from 0.5 μA up to 3 μA by applying 3 kV - 12 kV voltage to the corona electrode and makes possible selection among the types of corona electrodes (needle, multi-needle, wire, etc.). The results of experimental testing of the poling setup show that at fixed optimal operational parameters of poling - the sample orientation temperature and the discharge current - the corona charging of polymeric materials can successfully be performed applying the two-electrode technique. To study the dynamics of both poling and charge transport processes the three-electrode charging system - a corona triode - should be applied.

Potential efficiencies of open- and closed-cycle CO, supersonic, electric-discharge lasers

NASA Technical Reports Server (NTRS)

Monson, D. J.

1976-01-01

Computed open- and closed-cycle system efficiencies (laser power output divided by electrical power input) are presented for a CW carbon monoxide, supersonic, electric-discharge laser. Closed-system results include the compressor power required to overcome stagnation pressure losses due to supersonic heat addition and a supersonic diffuser. The paper shows the effect on the system efficiencies of varying several important parameters. These parameters include: gas mixture, gas temperature, gas total temperature, gas density, total discharge energy loading, discharge efficiency, saturated gain coefficient, optical cavity size and location with respect to the discharge, and supersonic diffuser efficiency. Maximum open-cycle efficiency of 80-90% is predicted; the best closed-cycle result is 60-70%.

Characterization of electrical discharges on Teflon dielectrics used as spacecraft thermal control

NASA Technical Reports Server (NTRS)

Yadlowsky, E. J.; Hazelton, R. C.; Churchill, R. J.

1979-01-01

The dual effects of system degradation and reduced life of synchronous-orbit satellites as a result of differential spacecraft charging underscore the need for a clearer understanding of the prevailing electrical discharge phenomena. In a laboratory simulation, the electrical discharge current, surface voltage, emitted particle fluxes, and photo-emission associated with discharge events on electron beam irradiated silver-backed Teflon samples were measured. Sample surface damage was examined with optical and electron beam microscopes. The results are suggestive of a model in which the entire sample surface is discharged by lateral sub-surface currents flowing from a charge deposition layer through a localized discharge channel to the back surface of the sample. The associated return current pulse appears to have a duration which may be a signature by which different discharge processes may be characterized.

Plans of lightning and airglow measurements with LAC/Akatsuki

NASA Astrophysics Data System (ADS)

Takahashi, Yukihiro; Hoshino, Naoya; Sato, Mitsuteru; Yair, Yoav; Galand, Marina; Fukuhara, Tetsuya

Though there are extensive researches on the existence of lightning discharge in Venus over few decades, this issue is still under controversial. Recently it is reported that the magnetometer on board Venus Express detected whistler mode waves whose source could be lightning discharge occurring well below the spacecraft. However, it is too early to determine the origin of these waves. On the other hand, night airglow is expected to provide essential information on the atmospheric circulation in the upper atmosphere of Venus. But the number of consecutive images of airglow obtained by spacecraft is limited and even the variations of most enhanced location is still unknown. In order to identify the discharge phenomena in the atmosphere of Venus separating from noises and to know the daily variation of airglow distribution in night-side disk, we plan to observe the lightning and airglow optical emissions with high-speed and high-sensitivity optical detector with narrow-band filters on board Akatsuki. We are ready to launch the flight model of lightning and airglow detector, LAC (Lightning and Airglow Camera). Main difference from other previous equipments which have provided evidences of lightning existence in Venus is the high-speed sampling rate at 32 us interval for each pixel, enabling us to distinguish the optical lightning flash from other pulsing noises. In this presentation the observation strategies, including ground-based support with optical telescopes, are shown and discussed.

Optical characteristics and parameters of gas-discharge plasma in a mixture of mercury dibromide vapor with neon

NASA Astrophysics Data System (ADS)

Malinina, A. A.; Malinin, A. N.

2013-12-01

Results are presented from studies of the optical characteristics and parameters of plasma of a dielectric barrier discharge in a mixture of mercury dibromide vapor with neon—the working medium of a non-coaxial exciplex gas-discharge emitter. The electron energy distribution function, the transport characteristics, the specific power losses for electron processes, the electron density and temperature, and the rate constants for the processes of elastic and inelastic electron scattering by the working mixture components are determined as functions of the reduced electric field. The rate constant of the process leading to the formation of exciplex mercury monobromide molecules is found to be 1.6 × 10-14 m3/s for a reduced electric field of E/ N = 15 Td, at which the maximum emission intensity in the blue-green spectral region (λmax = 502 nm) was observed in this experiment.

Thermal profiles for reaches of Snee-Oosh and Fornsby Creeks, Swinomish Indian Reservation, northwestern Washington, July 2013

USGS Publications Warehouse

Gendaszek, Andrew S.; Opatz, Chad C.

2013-01-01

Longitudinal profiles of streambed temperatures were measured in approximately 225-m-long reaches of the Snee-Oosh and Fornsby Creeks in the Swinomish Indian Reservation, northwestern Washington, during July 2013, to provide information about areas of groundwater discharge to streams. During summer, groundwater discharge is a source of cold water to streams and typically cools the surface water into which it discharges and buffers diurnal temperature fluctuations. Near-streambed temperatures were averaged over 1-m-long sections of cable during 1-minute periods every 30 minutes for 1-week periods using a fiber-optic distributed temperature sensor positioned on top of the streambed. The position of the fiber-optic cable was surveyed with a Global Positioning System. Stream temperatures and survey data are presented as Microsoft Excel® files consisting of date and time, water temperature, and geographical coordinates.

Electron density measurement in gas discharge plasmas by optical and acoustic methods

NASA Astrophysics Data System (ADS)

Biagioni, A.; Anania, M. P.; Bellaveglia, M.; Chiadroni, E.; Cianchi, A.; Di Giovenale, D.; Di Pirro, G.; Ferrario, M.; Filippi, F.; Mostacci, A.; Pompili, R.; Shpakov, V.; Vaccarezza, C.; Villa, F.; Zigler, A.

2016-08-01

Plasma density represents a very important parameter for both laser wakefield and plasma wakefield acceleration, which use a gas-filled capillary plasma source. Several techniques can be used to measure the plasma density within a capillary discharge, which are mainly based on optical diagnostic methods, as for example the well-known spectroscopic method using the Stark broadening effect. In this work, we introduce a preliminary study on an alternative way to detect the plasma density, based on the shock waves produced by gas discharge in a capillary. Firstly, the measurements of the acoustic spectral content relative to the laser-induced plasmas by a solid target allowed us to understand the main properties of the acoustic waves produced during this kind of plasma generation; afterwards, we have extended such acoustic technique to the capillary plasma source in order to calibrate it by comparison with the stark broadening method.

Factors controlling stream water nitrate and phosphor loads during precipitation events

NASA Astrophysics Data System (ADS)

Rozemeijer, J. C.; van der Velde, Y.; van Geer, F. G.; de Rooij, G. H.; Broers, H. P.; Bierkens, M. F. P.

2009-04-01

Pollution of surface waters in densely populated areas with intensive land use is a serious threat to their ecological, industrial and recreational utilization. European and national manure policies and several regional and local pilot projects aim at reducing pollution loads to surface waters. For the evaluation of measures, water authorities and environmental research institutes are putting a lot of effort into monitoring surface water quality. Fro regional surface water quality monitoring, the measurement locations are usually situated in the downstream part of the catchment to represent a larger area. The monitoring frequency is usually low (e.g. monthly), due to the high costs for sampling and analysis. As a consequence, human induced trends in nutrient loads and concentrations in these monitoring data are often concealed by the large variability of surface water quality caused by meteorological variations. Because natural surface water quality variability is poorly understood, large uncertainties occur in the estimates of (trends in) nutrient loads or average concentrations. This study aims at uncertainty reduction in the estimates of mean concentrations and loads of N and P from regional monitoring data. For this purpose, we related continuous N and P records of stream water to variations in precipitation, discharge, groundwater level and tube drain discharge. A specially designed multi scale experimental setup was installed in an agricultural lowland catchment in The Netherlands. At the catchment outlet, continuous measurements of water quality and discharge were performed from July 2007-January 2009. At an experimental field within the catchment continuous measurements of precipitation, groundwater levels and tube drain discharges were collected. 20 significant rainfall events with a variety of antecedent conditions, durations and intensities were selected for analysis. Singular and multiple regression analysis was used to identify relations between the continuous N and P records and characteristics of the dynamics of discharge, precipitation, groundwater level and tube drain discharge. From this study, we conclude that generally available and easy to measure explanatory data (such as continuous records of discharge, precipitation and groundwater level) can reduce uncertainty in estimations of N and P loads and mean concentrations. However, for capturing the observed short load pulses of P, continuous or discharge proportional sampling is needed.

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 compared to the traditional corona or dielectric barrier discharges. These conditions make the experimental evidence presented in this work valuable for the advancement of modeling and the theoretical understanding of the discharge in bubbles in water.

46 CFR 95.15-25 - Discharge outlets.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Discharge outlets. 95.15-25 Section 95.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-25 Discharge outlets. (a) Discharge outlets...

46 CFR 193.15-25 - Discharge outlets.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Discharge outlets. 193.15-25 Section 193.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 193.15-25 Discharge outlets. (a) Discharge outlets...

46 CFR 76.15-25 - Discharge outlets.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 3 2010-10-01 2010-10-01 false Discharge outlets. 76.15-25 Section 76.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-25 Discharge outlets. (a) Discharge outlets shall...

46 CFR 76.15-25 - Discharge outlets.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 3 2013-10-01 2013-10-01 false Discharge outlets. 76.15-25 Section 76.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-25 Discharge outlets. (a) Discharge outlets shall...

46 CFR 76.15-25 - Discharge outlets.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 3 2011-10-01 2011-10-01 false Discharge outlets. 76.15-25 Section 76.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-25 Discharge outlets. (a) Discharge outlets shall...

46 CFR 76.15-25 - Discharge outlets.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 3 2012-10-01 2012-10-01 false Discharge outlets. 76.15-25 Section 76.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-25 Discharge outlets. (a) Discharge outlets shall...

46 CFR 76.15-25 - Discharge outlets.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 3 2014-10-01 2014-10-01 false Discharge outlets. 76.15-25 Section 76.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 76.15-25 Discharge outlets. (a) Discharge outlets shall...

46 CFR 95.15-25 - Discharge outlets.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Discharge outlets. 95.15-25 Section 95.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-25 Discharge outlets. (a) Discharge outlets...

46 CFR 95.15-25 - Discharge outlets.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Discharge outlets. 95.15-25 Section 95.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-25 Discharge outlets. (a) Discharge outlets...

46 CFR 193.15-25 - Discharge outlets.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Discharge outlets. 193.15-25 Section 193.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 193.15-25 Discharge outlets. (a) Discharge outlets...

32 CFR 724.403 - President, Naval Discharge Review Board.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false President, Naval Discharge Review Board. 724.403 Section 724.403 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL..., Naval Discharge Review Board. Supervises the Naval Discharge Review Board. (See subpart C). ...

32 CFR 724.102 - Naval Discharge Review Board.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Naval Discharge Review Board. 724.102 Section 724.102 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.102 Naval Discharge Review Board. An administrative board, referred...

32 CFR 724.102 - Naval Discharge Review Board.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Naval Discharge Review Board. 724.102 Section 724.102 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.102 Naval Discharge Review Board. An administrative board, referred...

32 CFR 724.403 - President, Naval Discharge Review Board.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false President, Naval Discharge Review Board. 724.403 Section 724.403 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL..., Naval Discharge Review Board. Supervises the Naval Discharge Review Board. (See subpart C). ...

Stage-discharge relations and annual nitrogen and phosphorus load estimates for stream sites in the Elk River Basin, 2006–2008

USGS Publications Warehouse

Hoos, Anne B.; Williams, Shannon D.; Wolfe, William J.

2016-11-22

The U.S. Geological Survey, in cooperation with the Tennessee Department of Environment and Conservation (TDEC), measured continuous discharge at 4 water-quality monitoring sites and developed stage-discharge ratings for 10 additional water-quality monitoring sites in the Elk River Basin during 2006 through 2008. The discharge data were collected to support stream load assessments by TDEC. Annual nitrogen and phosphorus loads were estimated for the four sites where continuous daily discharge records were collected. Reported loads for the period 2006 through 2008 are not representative of long-term mean annual conditions at the sites in this study, however, because of severe drought conditions in the Elk River Basin during this period.

Clearance of short circuited ion optics electrodes by capacitive discharge. [in ion thrusters

NASA Technical Reports Server (NTRS)

Poeschel, R. L.

1976-01-01

The ion optics electrodes of low specific impulse (3000 sec) mercury electron bombardment ion thrusters are vulnerable to short circuits by virtue of their relatively small interelectrode spacing (0.5 mm). Metallic flakes from backsputtered deposits are the most probable cause of such 'shorts' and 'typical' flakes have been simulated here using refractory wire that has a representative, but controllable, cross section. Shorting wires can be removed by capacitive discharge without significant damage to the electrodes. This paper describes an evaluation of 'short' removal versus electrode damage for several combinations of capacitor voltage, stored energy, and short circuit conditions.

Direct determination of arsenic in steel by glow discharge optical emission spectrometry with argon-helium mixed gas.

PubMed

Wagatsuma, Kazuaki

2003-02-01

In glow discharge optical emission spectrometry, an argon-helium mixed gas plasma was investigated to improve the detection sensitivity of arsenic in steel samples. The emission line of arsenic was enhanced and the background intensity was simultaneously reduced when an Ar-He plasma was employed instead of an Ar plasma, which is effective for the sensitive determination of arsenic. The detection limits were calculated to be 0.009 mass% for a 700-V Ar plasma, 0.004 mass% for a 700-V Ar-He plasma, and 0.001 mass% for a 900-V Ar-He plasma.

The formation of diffuse discharge by short-front nanosecond voltage pulses and the modification of dielectrics in this discharge

NASA Astrophysics Data System (ADS)

Orlovskii, V. M.; Panarin, V. A.; Shulepov, M. A.

2014-07-01

The dynamics of diffuse discharge formation under the action of nanosecond voltage pulses with short fronts (below 1 ns) in the absence of a source of additional preionization and the influence of a dielectric film on this process have been studied. It is established that the diffuse discharge is induced by the avalanche multiplication of charge initiated by high-energy electrons and then maintained due to secondary breakdowns propagating via ionized gas channels. If a dielectric film (polyethylene, Lavsan, etc.) is placed on the anode, then multiply repeated discharge will lead to surface and bulk modification of the film material. Discharge-treated polyethylene film exhibits a change in the optical absorption spectrum in the near-IR range.

Formation of Nitrogen Oxides in an Apokamp-Type Plasma Source

NASA Astrophysics Data System (ADS)

Sosnin, É. A.; Goltsova, P. A.; Panarin, V. A.; Skakun, V. S.; Tarasenko, V. F.; Didenko, M. V.

2017-08-01

Using optical and chemical processes, the composition of the products of decay of the atmospheric-pressure non-equilibrium plasma is determined in a pulsed, high-voltage discharge in the modes of apokampic and corona discharges. It is shown that the products of decay primarily contain nitrogen oxides NO x, and in the mode of the corona discharge - ozone. Potential applications of this source of plasma are discussed with respect to plasma processing of the seeds of agricultural crops.

Light-Shifts of an Integrated Filter-Cell Rubidium Atomic Clock

DTIC Science & Technology

2015-05-25

the light-shift coefficient for two different rf- discharge lamps (i.e., a pure 87Rb lamp and a lamp filled with the natural Rb isotope abundance...for the Galileo Rb clock under the assumption of a natural (or 85Rb isotopically enriched) rf- discharge lamp for the Galileo clock. I...satellites [14]. 6.8347… GHz 85Rb Filter Cell Cell Resonance Photodiode Microwave Cavity 87Rb Discharge Lamp 87Rb & N2 Rb & Xe, Kr Optical Pumping 87Rb

Optical-Fiber-Welding Machine

NASA Technical Reports Server (NTRS)

Goss, W. C.; Mann, W. A.; Goldstein, R.

1985-01-01

Technique yields joints with average transmissivity of 91.6 percent. Electric arc passed over butted fiber ends to melt them together. Maximum optical transmissivity of joint achieved with optimum choice of discharge current, translation speed, and axial compression of fibers. Practical welding machine enables delicate and tedious joining operation performed routinely.

46 CFR 76.17-20 - Discharge outlets.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 3 2011-10-01 2011-10-01 false Discharge outlets. 76.17-20 Section 76.17-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Foam Extinguishing Systems, Details § 76.17-20 Discharge outlets. (a) Discharge outlets shall be of an...

46 CFR 95.17-20 - Discharge outlets.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Discharge outlets. 95.17-20 Section 95.17-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Foam Extinguishing Systems, Details § 95.17-20 Discharge outlets. (a) Discharge outlets shall be...

46 CFR 95.17-20 - Discharge outlets.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Discharge outlets. 95.17-20 Section 95.17-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Foam Extinguishing Systems, Details § 95.17-20 Discharge outlets. (a) Discharge outlets shall be...

46 CFR 76.17-20 - Discharge outlets.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 3 2010-10-01 2010-10-01 false Discharge outlets. 76.17-20 Section 76.17-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Foam Extinguishing Systems, Details § 76.17-20 Discharge outlets. (a) Discharge outlets shall be of an...

32 CFR 724.402 - Naval Discharge Review Board.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Naval Discharge Review Board. 724.402 Section 724.402 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Principal Elements of the Navy Department Discharge Review System § 724.402 Naval...

32 CFR 724.204 - Eligibility for naval discharge review.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Eligibility for naval discharge review. 724.204 Section 724.204 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Authority/Policy for Departmental Discharge Review § 724.204 Eligibility for naval...

32 CFR 724.402 - Naval Discharge Review Board.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Naval Discharge Review Board. 724.402 Section 724.402 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Principal Elements of the Navy Department Discharge Review System § 724.402 Naval...

32 CFR 724.204 - Eligibility for naval discharge review.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Eligibility for naval discharge review. 724.204 Section 724.204 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Authority/Policy for Departmental Discharge Review § 724.204 Eligibility for naval...

Fiber fuse behavior in kW-level continuous-wave double-clad field laser

NASA Astrophysics Data System (ADS)

Jun-Yi, Sun; Qi-Rong, Xiao; Dan, Li; Xue-Jiao, Wang; Hai-Tao, Zhang; Ma-Li, Gong; Ping, Yan

2016-01-01

In this study, original experimental data for fiber fuse in kW-level continuous-wave (CW) high power double-clad fiber (DCF) laser are reported. The propagating velocity of the fuse is 9.68 m/s in a 3.1-kW Yb-doped DCF laser. Three other cases in Yb-doped DCF are also observed. We think that the ignition of fiber fuse is caused by thermal mechanism, and the formation of bullet-shaped tracks is attributed to the optical discharge and temperature gradient. The inducements of initial fuse and formation of bullet-shaped voids are analyzed. This investigation of fiber fuse helps better understand the fiber fuse behavior, in order to avoid the catastrophic destruction caused by fiber fuse in high power fiber laser. Project supported by the Key Laboratory of Science and Technology on High Energy Laser and China Academy of Engineering Physics (Grant No. 2014HEL02) and the National Natural Science Foundation of China (Grant No. 61307057).

40 CFR 464.44 - New source performance standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 29 2010-07-01 2010-07-01 false New source performance standards. 464...

40 CFR 464.14 - New source performance standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2013-07-01 2013-07-01 false New source performance standards. 464...

40 CFR 464.14 - New source performance standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 29 2010-07-01 2010-07-01 false New source performance standards. 464...

40 CFR 464.44 - New source performance standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2014-07-01 2014-07-01 false New source performance standards. 464...

40 CFR 464.24 - New source performance standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2013-07-01 2013-07-01 false New source performance standards. 464...

40 CFR 464.24 - New source performance standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2011-07-01 2011-07-01 false New source performance standards. 464...

40 CFR 464.24 - New source performance standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 29 2010-07-01 2010-07-01 false New source performance standards. 464...

40 CFR 464.44 - New source performance standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2013-07-01 2013-07-01 false New source performance standards. 464...

40 CFR 464.44 - New source performance standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2012-07-01 2012-07-01 false New source performance standards. 464...

40 CFR 464.24 - New source performance standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2014-07-01 2014-07-01 false New source performance standards. 464...

40 CFR 464.44 - New source performance standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2011-07-01 2011-07-01 false New source performance standards. 464...

40 CFR 464.24 - New source performance standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2012-07-01 2012-07-01 false New source performance standards. 464...

40 CFR 464.14 - New source performance standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2014-07-01 2014-07-01 false New source performance standards. 464...

40 CFR 464.14 - New source performance standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2011-07-01 2011-07-01 false New source performance standards. 464...

40 CFR 464.14 - New source performance standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2012-07-01 2012-07-01 false New source performance standards. 464...

Intense laser pulse propagation in capillary discharge plasma channels

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

Hubbard, R.F.; Moore, C.I.; Sprangle, P.

Optical guiding of intense laser pulses is required for plasma-based accelerator concepts such as the laser wakefield accelerator. Reported experiments have successfully transported intense laser pulses in the hollow plasma column produced by a capillary discharge. The hollow plasma has an index of refraction which peaks on-axis, thus providing optical guiding which overcomes beam expansion due to diffraction. In more recent experiments at Hebrew University, 800 nm wavelength, 0.1 mJ, 100 fs pulses have been guided in {approximately}300 micron radius capillaries over distances as long as 6.6 cm. Simulations of these experiments using a 2-D nonlinear laser propagation model producemore » the expected optical guiding, with the laser pulse radius r{sub L} exhibiting oscillations about the equilibrium value predicted by an analytical envelope equation model. The oscillations are damped at the front of the pulse and grow in amplitude in the back of the pulse. This growth and damping is attributed to finite pulse length effects. Simulations also show that further ionization of the discharge plasma by the laser pulse may hollow the laser pulse and introduce modulations in the spot size. This ionization-defocusing effect is expected to be significant at the high intensities required for accelerator application. Capillary discharge experiments at much higher intensities are in progress on the Naval Research Laboratory T{sup 3} laser, and preliminary results are reported. {copyright} {ital 1999 American Institute of Physics.}« less

Plasma treatment of polyethylene tubes in continuous regime using surface dielectric barrier discharge with water electrodes

NASA Astrophysics Data System (ADS)

Galmiz, Oleksandr; Zemánek, Miroslav; Pavliňák, David; Černák, Mirko

2018-05-01

Combining the surface dielectric barrier discharges generated in contact with water based electrolytes, as the discharge electrodes, we have designed a new type of surface electric discharge, generating thin layers of plasma which propagate along the treated polymer surfaces. The technique was aimed to achieve uniform atmospheric pressure plasma treatment of polymeric tubes and other hollow bodies. The results presented in this work show the possibility of such system to treat outer surface of polymer materials in a continuous mode. The technical details of experimental setup are discussed as well as results of treatment of polyethylene tubes are shown.

Spectroscopic study of bipolar nanosecond pulse gas-liquid discharge in atmospheric argon

NASA Astrophysics Data System (ADS)

Sen, WANG; Dezheng, YANG; Feng, LIU; Wenchun, WANG; Zhi, FANG

2018-07-01

Atmospheric gas-liquid discharge with argon as a working gas is presented by employed nanosecond pulse power. The discharge is presented in a glow-like mode. The discharge powers are determined to be less than 1 W, and remains almost constant when the discharge duration time increases. Bountiful active species are determined by capturing optical emission spectra, and their main generation processes are also discussed. The plasma gas temperature is calculated as 350 K by comparing the experimental spectra and the simulated ones of {{{N}}}2({{C}}{}3{{\\Pi }}{{g}}\\to {{B}}{}3{{\\Pi }}{{g}},{{Δ }}{{ν }}=-2). The time resolved vibrational and rotational temperature is researched to present the stability of discharge when pulse voltage and discharge duration vary. The electron density is determined to be 1016 cm‑3 according to the Stark broadening effect of the H α line.

Removal of NO in NO/N2, NO/N2/O2, NO/CH4/N2, and NO/CH4/O2/N2 systems by flowing microwave discharges.

PubMed

Hueso, José L; Gonzalez-Elipe, Agustín R; Cotrino, José; Caballero, Alfonso

2007-02-15

In this paper, continuing previous work, we report on experiments carried out to investigate the removal of NO from simulated flue gas in nonthermal plasmas. The plasma-induced decomposition of small concentrations of NO in N2 used as the carrier gas and O2 and CH4 as minority components has been studied in a surface wave discharge induced with a surfatron launcher. The reaction products and efficiency have been monitored by mass spectrometry as a function of the composition of the mixture. NO is effectively decomposed into N2 and O2 even in the presence of O2, provided always that enough CH4 is also present in the mixture. Other majority products of the plasma reactions under these conditions are NH3, CO, and H2. In the absence of O2, decomposition of NO also occurs, although in that case HCN accompanies the other reaction products as a majority component. The plasma for the different reaction mixtures has been characterized by optical emission spectroscopy. Intermediate excited species of NO*, C*, CN*, NH*, and CH* have been monitored depending on the gas mixture. The type of species detected and their evolution with the gas composition are in agreement with the reaction products detected in each case. The observations by mass spectrometry and optical emission spectroscopy are in agreement with the kinetic reaction models available in literature for simple plasma reactions in simple reaction mixtures.

Lasers '92; Proceedings of the International Conference on Lasers and Applications, 15th, Houston, TX, Dec. 7-10, 1992

NASA Technical Reports Server (NTRS)

Wang, Charles P. (Editor)

1993-01-01

Papers from the conference are presented, and the topics covered include the following: x-ray lasers, excimer lasers, chemical lasers, high power lasers, blue-green lasers, dye lasers, solid state lasers, semiconductor lasers, gas and discharge lasers, carbon dioxide lasers, ultrafast phenomena, nonlinear optics, quantum optics, dynamic gratings and wave mixing, laser radar, lasers in medicine, optical filters and laser communication, optical techniques and instruments, laser material interaction, and industrial and manufacturing applications.

Frequency of streamflow measurements required to determine forest treatment effects

Treesearch

Kenneth G. Reinhart

1964-01-01

Most of the stream-discharge records for our experimental watersheds are taken by continuous measurements. But the question arises: are continuous measurements necessary to determine effects of forest treatments? Or could treatment effects be determined by measurement of discharge at intervals, say, once a day or once a week?

34 CFR 686.42 - Discharge of agreement to serve.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 34 Education 4 2011-07-01 2011-07-01 false Discharge of agreement to serve. 686.42 Section 686.42 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION (CONTINUED) TEACHER EDUCATION ASSISTANCE FOR COLLEGE AND HIGHER EDUCATION...

Needle-array to Plate DBD Plasma Using Sine AC and Nanosecond Pulse Excitations for Purpose of Improving Indoor Air Quality

PubMed Central

Zhang, Li; Yang, Dezheng; Wang, Wenchun; Wang, Sen; Yuan, Hao; Zhao, Zilu; Sang, Chaofeng; Jia, Li

2016-01-01

In this study, needle-array to plate electrode configuration was employed to generate an atmospheric air diffuse discharge using both nanosecond pulse and sine AC voltage as excitation voltage for the purpose of improving indoor air quality. Different types of voltage sources and electrode configurations are employed to optimize electrical field distribution and improve discharge stability. Discharge images, electrical characteristics, optical emission spectra, and plasma gas temperatures in both sine AC discharge and nanosecond pulse discharge were compared and the discharge stability during long operating time were discussed. Compared with the discharge excited by sine AC voltage, the nanosecond pulsed discharge is more homogenous and stable, besides, the plasma gas temperature of nanosecond pulse discharge is much lower. Using packed-bed structure, where γ- Al2O3 pellets are filled in the electrode gap, has obvious efficacy in the production of homogenous discharge. Furthermore, both sine AC discharge and nanosecond pulse discharge were used for removing formaldehyde from flowing air. It shows that nanosecond pulse discharge has a significant advantage in energy cost. And the main physiochemical processes for the generation of active species and the degradation of formaldehyde were discussed. PMID:27125663

Generation of large-area and glow-like surface discharge in atmospheric pressure air

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

Song, Ying; Bi, Zhenhua; Wang, Xueyang

2016-08-15

A large-area (6 cm × 6 cm) air surface dielectric barrier discharge has been generated at atmospheric pressure by using well-aligned and micron-sized dielectric tubes with tungsten wire electrodes. Intensified CCD images with an exposure time of 5 ns show that the uniform surface air discharge can be generated during the rising and falling time of pulsed DC voltage. Current and voltage and optical measurements confirm the formation of glow-like air discharges on the surface of micron-sized dielectric tubes. Simulation results indicate that the microelectrode configuration contributes to the formation of strong surface electric field and plays an important role in the generation of uniformmore » surface air discharge.« less

Note: Characterization of the plasma parameters of a capillary discharge-produced plasma channel waveguide to guide an intense laser pulse

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

Higashiguchi, Takeshi; Yugami, Noboru; CREST, Japan Science and Technology Agency, 4-1-8 Honcho, Kanagawa, Saitama 332-0012

2010-04-15

We demonstrated the production of an optical waveguide in a capillary discharge-produced plasma using a cylindrical capillary. Plasma parameters of its waveguide were characterized by use of both a Nomarski laser interferometer and a hydrogen plasma line spectrum. A space-averaged maximum temperature of 3.3 eV with electron densities of the order of 10{sup 17} cm{sup -3} was observed at a discharge time of 150 ns and a maximum discharge current of 400 A. An ultrashort, intense laser pulse was guided by use of this plasma channel.

32 CFR 724.118 - Documentary discharge review.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 5 2013-07-01 2013-07-01 false Documentary discharge review. 724.118 Section 724.118 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.118 Documentary discharge review. A formal session of the NDRB convened for the purpose of reviewing, on the...

32 CFR 724.118 - Documentary discharge review.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 32 National Defense 5 2014-07-01 2014-07-01 false Documentary discharge review. 724.118 Section 724.118 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.118 Documentary discharge review. A formal session of the NDRB convened for the purpose of reviewing, on the...

32 CFR 724.118 - Documentary discharge review.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Documentary discharge review. 724.118 Section 724.118 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.118 Documentary discharge review. A formal session of the NDRB convened for the purpose of reviewing, on the...

32 CFR 724.118 - Documentary discharge review.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Documentary discharge review. 724.118 Section 724.118 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.118 Documentary discharge review. A formal session of the NDRB convened for the purpose of reviewing, on the...

32 CFR 724.118 - Documentary discharge review.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 5 2012-07-01 2012-07-01 false Documentary discharge review. 724.118 Section 724.118 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.118 Documentary discharge review. A formal session of the NDRB convened for the purpose of reviewing, on the...

32 CFR 724.304 - Responsibility for Department of the Navy support of the Naval Discharge Review Board.

Code of Federal Regulations, 2011 CFR

2011-07-01

... support of the Naval Discharge Review Board. 724.304 Section 724.304 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Director, Secretary of the Navy Council of Review Boards and President Naval Discharge Review Board; Responsibilities in...

32 CFR 724.304 - Responsibility for Department of the Navy support of the Naval Discharge Review Board.

Code of Federal Regulations, 2010 CFR

2010-07-01

... support of the Naval Discharge Review Board. 724.304 Section 724.304 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Director, Secretary of the Navy Council of Review Boards and President Naval Discharge Review Board; Responsibilities in...

32 CFR 865.122 - Summary of statistics for Discharge Review Board.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 6 2010-07-01 2010-07-01 false Summary of statistics for Discharge Review Board. 865.122 Section 865.122 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE... statistics for Discharge Review Board. The Air Force Discharge Review Board shall prepare and provide to the...

ZnO Nanowire-Based Corona Discharge Devices Operated Under Hundreds of Volts.

PubMed

Yang, Wenming; Zhu, Rong; Zong, Xianli

2016-12-01

Minimizing the voltage of corona discharges, especially when using nanomaterials, has been of great interest in the past decade or so. In this paper, we report a new corona discharge device by using ZnO nanowires operated in atmospheric air to realize continuous corona discharge excited by hundreds of volts. ZnO nanowires were synthesized on microelectrodes using electric-field-assisted wet chemical method, and a thin tungsten film was deposited on the microchip to enhance discharging performance. The testing results showed that the corona inception voltages were minimized greatly by using nanowires compared to conventional dischargers as a result of the local field enhancement of nanowires. The corona could be continuously generated and self-sustaining. It was proved that the law of corona inception voltage obeyed the conventional Peek's breakdown criterion. An optimal thickness of tungsten film coated over ZnO nanowires was figured out to obtain the lowest corona inception voltage. The ion concentration of the nanowire-based discharger attained 10(17)/m(3) orders of magnitude, which is practicable for most discharging applications.

Continuous pressure letdown system

DOEpatents

Sprouse, Kenneth M.; Matthews, David R.; Langowski, Terry

2010-06-08

A continuous pressure letdown system connected to a hopper decreases a pressure of a 2-phase (gas and solid) dusty gas stream flowing through the system. The system includes a discharge line for receiving the dusty gas from the hopper, a valve, a cascade nozzle assembly positioned downstream of the discharge line, a purge ring, an inert gas supply connected to the purge ring, an inert gas throttle, and a filter. The valve connects the hopper to the discharge line and controls introduction of the dusty gas stream into the discharge line. The purge ring is connected between the discharge line and the cascade nozzle assembly. The inert gas throttle controls a flow rate of an inert gas into the cascade nozzle assembly. The filter is connected downstream of the cascade nozzle assembly.

Electrical Versus Optical: Comparing Methods for Detecting Terahertz Radiation Using Neon Lamps

NASA Astrophysics Data System (ADS)

Slocombe, L. L.; Lewis, R. A.

2018-05-01

Terahertz radiation impinging on a lit neon tube causes additional ionization of the encapsulated gas. As a result, the electrical current flowing between the electrodes increases and the glow discharge in the tube brightens. These dual phenomena suggest two distinct modes of terahertz sensing. The electrical mode simply involves measuring the electrical current. The optical mode involves monitoring the brightness of the weakly ionized plasma glow discharge. Here, we directly compare the two detection modes under identical experimental conditions. We measure 0.1-THz radiation modulated at frequencies in the range 0.1-10 kHz, for lamp currents in the range 1-10 mA. We find that electrical detection provides a superior signal-to-noise ratio while optical detection has a faster response. Either method serves as the basis of a compact, robust, and inexpensive room-temperature detector of terahertz radiation.

Study of the dc and 100kHz glow discharges in acetylene-nitrogen mixture by means of optical emission spectroscopy

NASA Astrophysics Data System (ADS)

Jamroz, P.; Zyrnicki, W.

2002-09-01

The dc and 100 kHz low pressure discharges in acetylene-nitrogen mixture have been studied here. Optical emission spectroscopy was used for identification of active plasma components and to determine plasma temperature. Relative concentrations of H, CH and CN were investigated versus experimental conditions by optical actinometry techniques. Emission intensities of N2 and N2^+ normalized to intensity of argon line were also monitored as a function of experimental parameters. The rotational temperatures from the N2^+ B^2Σ_u^+-X^2Σ_g^+ (0-0) and CN B^2Σ^+-X^2Σ^+ (0-0) bands and vibrational temperatures from the CN (B^2Σ^+-X^2Σ^+) and N2 (C^3Pi_u-B^3Pi_g) spectra were determined. Plasma processes and plasma equilibrium state were discussed.

On the effects of thermal wake from the optical pulsating discharge on the body aerodynamic drag

NASA Astrophysics Data System (ADS)

Kiseleva, T. A.; Golyshev, A. A.; Yakovlev, V. I.; Orishich, A. M.

2018-03-01

The effect of an optical pulsed discharge created by CO2-laser with an average power of 1.8 kW on the aerodynamic drag of a model in a supersonic air flow is experimentally investigated. Experiments were carried out in a supersonic wind tunnel MAU-M (diameter of the nozzle outlet dc = 50 mm) on the modes M = 1,36, Re1 = 1.4-3.8*107 1/m. To ensure a stable optical breakdown, a jet of argon gas was introduced into the focusing region of the laser beam. As a result, a decrease in the aerodynamic drag force was obtained. It is shown, that the increasing of the laser pulses repetition frequency leads to the decreasing in the aerodynamic drag force. The maximum decrease was 15% at a maximum frequency f = 90 kHz.

Structural and thermal response of 30 cm diameter ion thruster optics

NASA Technical Reports Server (NTRS)

Macrae, G. S.; Zavesky, R. J.; Gooder, S. T.

1989-01-01

Tabular and graphical data are presented which are intended for use in calibrating and validating structural and thermal models of ion thruster optics. A 30 cm diameter, two electrode, mercury ion thruster was operated using two different electrode assembly designs. With no beam extraction, the transient and steady state temperature profiles and center electrode gaps were measured for three discharge powers. The data showed that the electrode mount design had little effect on the temperatures, but significantly impacted the motion of the electrode center. Equilibrium electrode gaps increased with one design and decreased with the other. Equilibrium displacements in excess of 0.5 mm and gap changes of 0.08 mm were measured at 450 W discharge power. Variations in equilibrium gaps were also found among assemblies of the same design. The presented data illustrate the necessity for high fidelity ion optics models and development of experimental techniques to allow their validation.

Study of a DC gas discharge with a copper cathode in a water flow

NASA Astrophysics Data System (ADS)

Tazmeev, G. Kh.; Timerkaev, B. A.; Tazmeev, Kh. K.

2017-07-01

A dc gas discharge between copper electrodes in the current range of 5-20 A was studied experimentally. The discharge gap length was varied within 45-70 mm. The cathode was a 10-mm-diameter rod placed in the water flowing out from a dielectric tube. Three discharge configurations differing in the position of the cathode upper end with respect to the water surface were considered: (i) above water; (ii) flush with the water surface, and (iii) under water. The electric and optical characteristics of the discharge in the second configuration were studied in more detail. It is established that the discharge properties are similar to those of an electric arc. Considerable cathode erosion was observed in the third configuration. It is revealed that fine-dispersed copper grains form in the course of erosion.

Recent studies on nanosecond-timescale pressurized gas discharges

DOE PAGES

Yatom, S.; Shlapakovski, A.; Beilin, L.; ...

2016-10-05

The results of recent experimental and numerical studies of nanosecond high-voltage discharges in pressurized gases are reviewed. The discharges were ignited in a diode filled by different gases within a wide range of pressures by an applied pulsed voltage or by a laser pulse in the gas-filled charged resonant microwave cavity. Fast-framing imaging of light emission, optical emission spectroscopy, X-ray foil spectrometry and coherent anti-Stokes Raman scattering were used to study temporal and spatial evolution of the discharge plasma density and temperature, energy distribution function of runaway electrons and dynamics of the electric field in the plasma channel. The resultsmore » obtained allow a deeper understanding of discharge dynamical properties in the nanosecond timescale, which is important for various applications of these types of discharges in pressurized gases.« less

FAST TRACK COMMUNICATION: Asymmetric surface barrier discharge plasma driven by pulsed 13.56 MHz power in atmospheric pressure air

NASA Astrophysics Data System (ADS)

Dedrick, J.; Boswell, R. W.; Charles, C.

2010-09-01

Barrier discharges are a proven method of generating plasmas at high pressures, having applications in industrial processing, materials science and aerodynamics. In this paper, we present new measurements of an asymmetric surface barrier discharge plasma driven by pulsed radio frequency (rf 13.56 MHz) power in atmospheric pressure air. The voltage, current and optical emission of the discharge are measured temporally using 2.4 kVp-p (peak to peak) 13.56 MHz rf pulses, 20 µs in duration. The results exhibit different characteristics to plasma actuators, which have similar discharge geometry but are typically driven at frequencies of up to about 10 kHz. However, the electrical measurements are similar to some other atmospheric pressure, rf capacitively coupled discharge systems with symmetric electrode configurations and different feed gases.

Characterization of a Plasmoid in the Afterglow of a Supersonic Flowing Microwave Discharge

NASA Technical Reports Server (NTRS)

Drake, D. J.; Miller, S.; Nikolic, M.; Popovic, S.; Vuskovic, L.

2009-01-01

We performed a detailed characterization a plasmoid in the afterglow region of an Ar supersonic microwave cavity discharge. The supersonic flow was generated using a convergent-divergent nozzle upstream of the discharge region. A cylindrical cavity was used to sustain a discharge in the pressure range of 100-600 Pa. Optical emission spectroscopy was used to observe populations of excited and ionic species in the plasmoid region. Plasmoid formation in the supersonic flowing afterglow located downstream from the primary microwave cavity discharge was characterized by measuring the radial and axial distributions of Argon excited states and Argon ions. More experiments are being carried out on the plasmoid to understand the discharge parameters within the region, i.e. rotational temperature, vibrational temperature, electron density, and how the electrodynamic and aerodynamic effects combine to form this plasmoid.

Process and continuous apparatus for chemical conversion of materials

DOEpatents

Rugg, Barry; Stanton, Robert

1983-01-01

A process and apparatus for the acid hydrolysis of waste cellulose to glucose of the type wherein waste cellulose is continuously fed into an inlet port of a twin screw extruder, water is continuously fed into reaction zone in the extruder, downstream of the inlet port, the cellulose is continuously reacted with water in the presence of an acid catalyst at elevated temperature and pressure in the reaction zone while being continuously conveyed to an outlet port of the extruder having a given diameter and the reacted cellulose is discharged from the extruder while the elevated temperature and pressure in the reaction zone is maintained. The elevated pressure is maintained by forming a dynamic seal zone at the upstream end of the reaction and continuously discharging the reacted material downstream of the outlet port at a predetermined volume rate of flow to maintain the pressure by passing the discharge through an orifice pipe having a smaller diameter than the given diameter of the outlet port.

Water dissociation in a radio-frequency electromagnetic field with ex situ electrodes—modelling of discharge initiation

NASA Astrophysics Data System (ADS)

Schneider, Jens; Holzer, Frank; Rabe, Carsten; Häupl, Tilmann; Kopinke, Frank-Dieter; Roland, Ulf

2013-04-01

Applying a new experimental design with a capillary glass reactor and plate electrodes outside of the reactor allowed the initiation of discharges in aqueous electrolytes under the influence of a radio-frequency (RF) electromagnetic field. This study focused on the mechanism leading to the initiation of such discharges in the restriction of a glass tube. The light emission correlated with discharges was analysed with optical emission spectroscopy. Electrons with energies between 20 and 45 eV were responsible for the dissociation of water molecules into (excited) OH, H and O radicals. Current-voltage characteristics were measured before and under discharge conditions. Modelling of the experimental setup and simulation of electrical field strength distribution support the hypothesis of the origin of discharges in general and experimental findings such as ring-shaped discharges and a minimum solution conductivity of about 1 S m-1 required for discharge initiation with RF voltages of 2 kV.

Contrasting dissolved organic carbon dynamics at two forested catchments interpreted from high-frequency optical sensor measurements

NASA Astrophysics Data System (ADS)

Saraceno, J.; Shanley, J. B.

2015-12-01

Stream dissolved organic carbon (DOC) concentrations can change rapidly during high-flow events. The timing and magnitude of these changes relative to the event hydrograph can yield insights about possible DOC sources its flow paths to the stream. In situ fluorescent dissolved organic matter (FDOM) sensors that generate high-frequency observations enable detailed examination of high-flow DOC- discharge hysteresis. In this presentation, we interpret high-flow DOC dynamics at two of the five U.S. Geological Survey (USGS) Water, Energy, and Biogeochemical Budgets (WEBB) sites - Panola Mountain, Georgia and Sleepers River, Vermont. Based on laboratory analyses of weekly and event grab samples, both USGS WEBB sites had a similar DOC ranges: from ~1 milligrams per liter (mg/L) at base flow to ~11-15 mg/L during the largest events. A curvilinear relationship between DOC and FDOM (corrected for temperature and turbidity interferences) was used to model a continuous time series of DOC. At the Sleepers River site, DOC showed a seasonal pattern of increasing DOC response; from fairly subdued during spring snowmelt, to a maximum during autumn leaf-fall. The DOC response to discharge showed a consistent clockwise hysteresis (DOC peak, lagged discharge peak). At the Panola Mountain site, maximum event DOC response was lower during wet conditions in the winter and spring. Hysteresis was less expressed at Panola Mountain relative to Sleepers River and displayed both clockwise and counterclockwise patterns, which were dependent on antecedent moisture conditions. The greater synchrony of DOC and discharge peaks at Panola Mountain suggests that DOC sources are closer to the stream and (or) move to the stream more quickly, than at Sleepers River.

An Examination of the Likelihood of Home Discharge After General Hospitalizations Among Medicaid Recipients

PubMed Central

Mkanta, William N.; Chumbler, Neale R.; Yang, Kai; Saigal, Romesh; Abdollahi, Mohammad; Mejia de Grubb, Maria C.; Ezekekwu, Emmanuel U.

2017-01-01

Ability to predict discharge destination would be a useful way of optimizing posthospital care. We conducted a cross-sectional, multiple state study of inpatient services to assess the likelihood of home discharges in 2009 among Medicaid enrollees who were discharged following general hospitalizations. Analyses were conducted using hospitalization data from the states of California, Georgia, Michigan, and Mississippi. A total of 33 160 patients were included in the study among which 13 948 (42%) were discharged to their own homes and 19 212 (58%) were discharged to continue with institutional-based treatment. A multiple logistic regression model showed that gender, age, race, and having ambulatory care-sensitive conditions upon admission were significant predictors of home-based discharges. Females were at higher odds of home discharges in the sample (odds ratio [OR] = 1.631; 95% confidence interval [CI], 1.520-1.751), while patients with ambulatory care-sensitive conditions were less likely to get home discharges (OR = 0.739; 95% CI, 0.684-0.798). As the nation engages in the continued effort to improve the effectiveness of the health care system, cost savings are possible if providers and systems of care are able to identify admission factors with greater prospects for in-home services after discharge.

New mechanism for lightning initiation

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

Roussel-Dupre, R.; Buchwald, M.; Gurevich, A.

1996-10-01

This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). To distinguish radio-frequency (rf) signals generated by lightning from the electromagnetic pulse produced by a nuclear explosion, it is necessary to understand the fundamental nature of thunderstorm discharges. The recent debate surrounding the origin of transionospheric pulse pairs (TIPPs) detected by the BLACKBEARD experiment aboard the ALEXIS satellite illustrates this point. We have argued that TIPP events could originate from the upward propagating discharges recently identified by optical images taken from the ground, from airplanes, and from the spacemore » shuttle. In addition, the Gamma Ray Observatory (GRO) measurements of x-ray bursts originating from thunderstorms are almost certainly associated with these upward propagating discharges. When taken together, these three measurements point directly to the runaway electron mechanism as the source of the upward discharges. The primary goal of this research effort was to identify the specific role played by the runaway-air-breakdown mechanism in the general area of thunderstorm electricity and in so doing develop lightning models that predict the optical, rf, and x-ray emissions that are observable from space.« less

Plasma cleaning of beamline optical components: Contamination and gas composition effects

NASA Astrophysics Data System (ADS)

Rosenberg, Richard A.; Smith, James A.; Wallace, Daniel J.

1992-01-01

We have initiated a program to study the impact of gas composition on the carbon removal rate during plasma cleaning of optical components, and of possible contamination due to the plasma processing. The measurements were performed in a test chamber designed to simulate the geometry of the grating/Codling mirror section of a Grasshopper monochromator. Removal rates were determined for a direct-current (dc) (Al electrode) discharge using a quartz crystal microbalance coated with polymethylmethacrylate, located at the position of the grating. Auger electron spectroscopy analysis of strateg- ically located, gold-coated stainless steel samples was employed to determine contamination. The relative removal rates of the gases studied were 3% C2F6/O2≫ O2+H2O≳O2˜N2O≳H2≳N2. Although the C2F6/O2 gas mixture showed a 20 times greater removal rate than its nearest competitor, it also caused significant contamination to occur. Contamination studies were performed for both dc and radio-frequency (rf) discharges. For the dc discharge we found that great care must be taken in order to avoid Al contamination; for the rf discharge, significant Fe contamination was observed.

Application of low temperature plasmas for restoration/conservation of archaeological objects

NASA Astrophysics Data System (ADS)

Krčma, F.; Blahová, L.; Fojtíková, P.; Graham, W. G.; Grossmannová, H.; Hlochová, L.; Horák, J.; Janová, D.; Kelsey, C. P.; Kozáková, Z.; Mazánková, V.; Procházka, M.; Přikryl, R.; Řádková, L.; Sázavská, V.; Vašíček, M.; Veverková, R.; Zmrzlý, M.

2014-12-01

The low-temperature low-pressure hydrogen based plasmas were used to study the influence of processes and discharge conditions on corrosion removal. The capacitive coupled RF discharge in the continuous or pulsed regime was used at operating pressure of 100-200 Pa. Plasma treatment was monitored by optical emission spectroscopy. To be able to study influence of various process parameters, the model corroded samples with and without sandy incrustation were prepared. The SEM-EDX analyzes were carried out to verify corrosion removal efficiency. Experimental conditions were optimized for the selected most frequent materials of original metallic archaeological objects (iron, bronze, copper, and brass). Chlorides removal is based on hydrogen ion reactions while oxides are removed mainly by neutral species interactions. A special focus was kept for the samples temperature because it was necessary to avoid any metallographic changes in the material structure. The application of higher power pulsed regime with low duty cycle seems be the best treatment regime. The low pressure hydrogen plasma is not applicable for objects with a very broken structure or for nonmetallic objects due to the non-uniform heat stress. Due to this fact, the new developed plasmas generated in liquids were applied on selected original archaeological glass materials.

In-SITU, Time-resolved Raman Spectro-micro-topography of an Operating Lithium Ion Battery

NASA Technical Reports Server (NTRS)

Luo, Yu; Cai, Wen-Bin; Xing, Xue-Kun; Scherson, Daniel A.

2003-01-01

A Raman microscope has been coupled to a computer-controlled, two-dimensional linear translator attached to a custom-designed, sealed optical chamber to allow in situ acquisition of space-, and time-resolved spectra of an operating thin graphite/LiCoO2 Li-ion battery. This unique arrangement made it possible to collect continuously series of Raman spectra from a sharply defined edge of the battery exposing the anode (A), separator (S), and cathode (C), during charge and discharge, while the device was moved back and forth under the fixed focused laser beam along an axis normal to the layered A/S/C plane. Clear spectral evidence was obtained for changes in the amount of Li(+) within particles of graphite in the anode, and, to a lesser extent, of LiCoO2 in the cathode, during battery discharge both as a function of position and time. Analysis of time-resolved Raman spectro-micro-topography (SMT) measurements of the type described in this work are expected to open new prospects for assessing the validity of theoretical models aimed at simulating the flow of Li(+) within Li-ion batteries under operating conditions.

46 CFR 53.05-5 - Discharge capacities and valve markings.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 2 2013-10-01 2013-10-01 false Discharge capacities and valve markings. 53.05-5 Section 53.05-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-5 Discharge capacities and valve markings. The discharge capacities and valve markings must...

46 CFR 53.05-5 - Discharge capacities and valve markings.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 2 2011-10-01 2011-10-01 false Discharge capacities and valve markings. 53.05-5 Section 53.05-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-5 Discharge capacities and valve markings. The discharge capacities and valve markings must...

46 CFR 53.05-5 - Discharge capacities and valve markings.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Discharge capacities and valve markings. 53.05-5 Section 53.05-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-5 Discharge capacities and valve markings. The discharge capacities and valve markings must...

46 CFR 53.05-5 - Discharge capacities and valve markings.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 2 2014-10-01 2014-10-01 false Discharge capacities and valve markings. 53.05-5 Section 53.05-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-5 Discharge capacities and valve markings. The discharge capacities and valve markings must...

46 CFR 53.05-5 - Discharge capacities and valve markings.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 2 2012-10-01 2012-10-01 false Discharge capacities and valve markings. 53.05-5 Section 53.05-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-5 Discharge capacities and valve markings. The discharge capacities and valve markings must...

Investigation on the Micro-Discharge Characteristics of Dielectric Barrier Discharge in a Needle-Plate Geometry

NASA Astrophysics Data System (ADS)

Li, Xuechen; Niu, Dongying; Jia, Pengying; Zhao, Na; Yuan, Ning

2011-04-01

In this study, a dielectric barrier discharge device with needle-plate electrodes was used to investigate the characteristics of the micro-discharge in argon at one atmospheric pressure by an optical method. The results show that there are two discharge modes in the dielectric barrier discharge, namely corona mode and filamentary mode. The corona discharge only occurs in the vicinity of the needle tip when the applied voltage is very low. However, the filamentary discharge mode can occur, and micro-discharge bridges the two electrodes when the applied voltage reaches a certain value. The extended area of micro-discharge on the dielectric plate becomes larger with the increase in applied voltage or decrease in gas pressure. The variance of the light emission waveforms is studied as a function of the applied voltage. Results show that very narrow discharge pulse only appears at the negative half cycle of the applied voltage in the corona discharge mode. However, broad hump (about several microseconds) can be discerned at both the negative half cycle and the positive half cycle for a high voltage in the filamentary mode. Furthermore, the inception voltage decreases and the width of the discharge hump increases with the increase in applied voltage. These experimental phenomena can be explained qualitatively by analyzing the discharge mechanism.

Measurements of the frequency stability of ultralow thermal expansion glass ceramic optical cavity lasers

NASA Astrophysics Data System (ADS)

Oram, R. J.; Latimer, I. D.; Spoor, S. P.

1997-05-01

This paper reports on a technique for providing a frequency-stabilized helium - neon gas laser by using inherently stable ultralow thermal expansion optical cavities. Four longitudinal monoblock cavity lasers were constructed and tested. These had their laser mirrors optically contacted to the bulk material. A 1 mm diameter hole along the axis of the block served as the discharge channel with electrodes optically contacted to the sides of the block. One of these lasers had a glass capilliary for the discharge channel. A fifth laser had a gain tube with Brewster angle windows fixed in a Zerodur box with the mirrors contacted to the ends. The warm-up characteristics of the five different lasers have been obtained and a theoretical model using finite element analysis was developed to determine the thermal expansion during warm-up. Using this computer model the thermal expansion coefficient of the material Zerodur was obtained. The results suggest that monoblock lasers can produce a free-running laser frequency stability of better than 10 MHz and show a repeatable warm-up characteristic of 100 MHz frequency drift.

How Lightning Works Inside Thunderstorms: A Half-Century of Lightning Studies

NASA Astrophysics Data System (ADS)

Krehbiel, P. R.

2015-12-01

Lightning is a fascinating and intriguing natural phenomenon, but the most interesting parts of lightning discharges are inside storms where they are obscured from view by the storm cloud. Although clouds are essentially opaque at optical frequencies, they are fully transparent at radio frequencies (RF). This, coupled with the fact that lightning produces prodigious RF emissions, has allowed us to image and study lightning inside storms using various RF and lower-frequency remote sensing techniques. As in all other scientific disciplines, the technology for conducting the studies has evolved to an incredible extent over the past 50 years. During this time, we have gone from having very little or no knowledge of how lightning operates inside storms, to being able to 'see' its detailed structure and development with an increasing degree of spatial and temporal resolution. In addition to studying the discharge processes themselves, lightning mapping observations provide valuable information on the electrical charge structure of storms, and on the mechanisms by which storms become strongly electrified. In this presentation we briefly review highlights of previous observations, focussing primarily on the long string of remote-sensing studies I have been involved in. We begin with the study of lightning charge centers of cloud-to-ground discharges in central New Mexico in the late 1960s and continue up to the present day with interferometric and 3-dimensional time-of-arrival VHF mapping observations of lightning in normally- and anomalously electrified storms. A particularly important aspect of the investigations has been comparative studies of lightning in different climatological regimes. We conclude with observations being obtained by a high-speed broadband VHF interferometer, which show in unprecedented detail how individual lightning discharges develop inside storms. From combined interferometer and 3-D mapping data, we are beginning to unlock nature's secrets concerning mysterious, high-power discharges known as narrow bipolar events (NBEs) and, more importantly, the long-standing question of how lightning is initiated inside storms.

Electric field measurement in microwave discharge ion thruster with electro-optic probe.

PubMed

Ise, Toshiyuki; Tsukizaki, Ryudo; Togo, Hiroyoshi; Koizumi, Hiroyuki; Kuninaka, Hitoshi

2012-12-01

In order to understand the internal phenomena in a microwave discharge ion thruster, it is important to measure the distribution of the microwave electric field inside the discharge chamber, which is directly related to the plasma production. In this study, we proposed a novel method of measuring a microwave electric field with an electro-optic (EO) probe based on the Pockels effect. The probe, including a cooling system, contains no metal and can be accessed in the discharge chamber with less disruption to the microwave distribution. This method enables measurement of the electric field profile under ion beam acceleration. We first verified the measurement with the EO probe by a comparison with a finite-difference time domain numerical simulation of the microwave electric field in atmosphere. Second, we showed that the deviations of the reflected microwave power and the beam current were less than 8% due to inserting the EO probe into the ion thruster under ion beam acceleration. Finally, we successfully demonstrated the measurement of the electric-field profile in the ion thruster under ion beam acceleration. These measurements show that the electric field distribution in the thruster dramatically changes in the ion thruster under ion beam acceleration as the propellant mass flow rate increases. These results indicate that this new method using an EO probe can provide a useful guide for improving the propulsion of microwave discharge ion thrusters.

Investigation on discharge characteristics of a coaxial dielectric barrier discharge reactor driven by AC and ns power sources

NASA Astrophysics Data System (ADS)

Qian, WANG; Feng, LIU; Chuanrun, MIAO; Bing, YAN; Zhi, FANG

2018-03-01

A coaxial dielectric barrier discharge (DBD) reactor with double layer dielectric barriers has been developed for exhaust gas treatment and excited either by AC power or nanosecond (ns) pulse to generate atmospheric pressure plasma. The comparative study on the discharge characteristics of the discharge uniformity, power deposition, energy efficiency, and operation temperature between AC and ns pulsed coaxial DBD is carried out in terms of optical and electrical characteristics and operation temperature for optimizing the coaxial DBD reactor performance. The voltages across the air gap and dielectric layer and the conduction and displacement currents are extracted from the applied voltages and measured currents of AC and ns pulsed coaxial DBDs for the calculation of the power depositions and energy efficiencies through an equivalent electrical model. The discharge uniformity and operating temperature of the coaxial DBD reactor are monitored and analyzed by optical images and infrared camera. A heat conduction model is used to calculate the temperature of the internal quartz tube. It is found that the ns pulsed coaxial DBD has a much higher instantaneous power deposition in plasma, a lower total power consumption, and a higher energy efficiency compared with that excited by AC power and is more homogeneous and stable. The temperature of the outside wall of the AC and ns pulse excited coaxial DBD reaches 158 °C and 64.3 °C after 900 s operation, respectively. The experimental results on the comparison of the discharge characteristics of coaxial DBDs excited by different powers are significant for understanding of the mechanism of DBDs, reducing energy loss, and optimizing the performance of coaxial DBD in industrial applications.

40 CFR 125.120 - Scope and purpose.

Code of Federal Regulations, 2010 CFR

2010-07-01

....120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS CRITERIA AND STANDARDS FOR THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM Ocean Discharge Criteria § 125.120 Scope... Elimination System (NPDES) permits for the discharge of pollutants from a point source into the territorial...

40 CFR 125.120 - Scope and purpose.

Code of Federal Regulations, 2011 CFR

2011-07-01

....120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS CRITERIA AND STANDARDS FOR THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM Ocean Discharge Criteria § 125.120 Scope... Elimination System (NPDES) permits for the discharge of pollutants from a point source into the territorial...

[Spectral investigation of atmospheric pressure plasma column].

PubMed

Li, Xue-Chen; Chang, Yuan-Yuan; Xu, Long-Fei

2012-07-01

Atmospheric pressure plasma column has many important applications in plasma stealth for aircraft. In the present paper, a plasma column with a length of 65 cm was generated in argon at atmospheric pressure by using dielectric barrier discharge device with water electrodes in coaxial configurations. The discharge mechanism of the plasma column was studied by optical method and the result indicates that a moving layer of light emission propagates in the upstream region. The propagation velocity of the plasma bullet is about 0.6 x 10(5) m x s(-1) through optical measurement. Spectral intensity ratios as functions of the applied voltage and driving frequency were also investigated by spectroscopic method. The variation in spectral intensity ratio implies a change in the averaged electron energy. Results show that the averaged electron energy increases with the increase in the applied voltage and the driving frequency. These results have significant values for industrial applications of the atmospheric pressure discharge and have extensive application potentials in stealth for military aircraft.

Highly porous micro-roughened structures developed on aluminum surface using the jet of rotating arc discharges at atmospheric pressure

NASA Astrophysics Data System (ADS)

Asadollahi, Siavash; Farzaneh, Masoud; Stafford, Luc

2018-02-01

Aluminum 6061 samples were exposed to the jet of an atmospheric pressure rotating arc discharge operated in either nitrogen or air. After multiple passes of treatment with an air-based plasma jet at very short source-to-substrate distances, scanning electron microscopy combined with x-ray photoelectron spectroscopy revealed a highly porous micro-roughened alumina-based structure on the surface of aluminum. Based on optical emission spectroscopy and high-speed optical imaging of the jet interacting with aluminum samples, it was found that the process is mainly driven by the energy transfer from the plasma source to the surface through transient plasma-transferred arcs. The occurrence of multiple arc discharges over very short time scales can induce rapid phase transformations of aluminum with characteristics similar to the ones usually observed during laser ablation of materials with femto- to nanosecond laser pulses or during the formation of cathode spots on the surface of metals.

Effect of electric discharge machining on the fatigue life of Inconel 718

NASA Technical Reports Server (NTRS)

Jeelani, S.; Collins, M. R.

1988-01-01

The effect of electric discharge machining on the fatigue life of Inconel 718 alloy at room temperature was investigated. Data were generated in the uniaxial tension fatigue mode at ambient temperature using flat 3.175 mm thick specimens. The specimens were machined on a wire-cut electric discharge machine at cutting speeds ranging from 0.5 to 2 mm per minute. The specimens were fatigued at a selected stress, and the resulting fatigue lives compared with that of the virgin material. The surfaces of the fatigued specimens were examined under optical and scanning electron microscopes, and the roughness of the surfaces was measured using a standard profilometer. From the results of the investigation, it was concluded that the fatigue life of the specimens machined using EDM decreased slightly as compared with that of the virgin material, but remained unchanged as the cutting speed was changed. The results are explained using data produced employing microhardness measurements, profilometry, and optical and scanning microscopy.

Fiber optic and laser sensors IX; Proceedings of the Meeting, Boston, MA, Sept. 3-5, 1991

NASA Technical Reports Server (NTRS)

Depaula, Ramon P. (Editor); Udd, Eric (Editor)

1991-01-01

The present volume on fiber-optic and laser sensors discusses industrial applications of fiber-optic sensors, fiber-optic temperature sensors, fiber-optic current sensors, fiber-optic pressure/displacement/vibration sensors, and generic fiber-optic systems. Attention is given to a fiber-sensor design for turbine engines, fiber-optic remote Fourier transform IR spectroscopy, near-IR fiber-optic temperature sensors, and an intensity-type fiber-optic electric current sensor. Topics addressed include fiber-optic magnetic field sensors based on the Faraday effect in new materials, diaphragm size and sensitivity for fiber-optic pressure sensors, a microbend pressure sensor for high-temperature environments, and linear position sensing by light exchange between two lossy waveguides. Also discussed are two-mode elliptical-core fiber sensors for measurement of strain and temperature, a fiber-optic interferometric X-ray dosimeter, fiber-optic interferometric sensors using multimode fibers, and optical fiber sensing of corona discharges.

Fundamental Study on Self-healing Insulation Performance of Silicone Rubber Affected by Local Breakdown

NASA Astrophysics Data System (ADS)

Hozumi, Naohiro; Nishioka, Koji; Suematsu, Takeshi; Murakami, Yoshinobu; Nagao, Masayuki; Sakata, Hiroshi

Feasibility of self-healing insulation system was studied. A silicone rubber without filler was mounted on a glass substrate with a needle electrode. An ac voltage with 4 kV in rms was applied. The voltage was cut off when the tree had propagated into 150 micrometers in length. After the cut-off, the partial discharge inception voltage was periodically observed. The partial discharge inception voltage had once reduced into as low as 2 kV. However, it gradually increased with time, and finally exceeded the tree inception voltage (4 kV) when 30 - 60 hours had passed. It was also observed by optical microscope that the tree gradually disappeared in parallel with the recovery of the partial discharge inception voltage. The same phenomenon was observed even if 1 kV ac voltage had been continuously applied during the process of the recovery. A simulation using a needle-shaped void was performed in order to clarify the mechanism of the self-healing effect. It was observed that the tip of the needle-shaped void gradually got wet with a liquid material. It would be the result of "bleed-out" of the low molecular component included in the rubber. The tip of the void was finally filled with the liquid, however, the rest of the needle-shaped void stayed without being filled. In this type of tree, it was suggested that the self-healing effect is expected if the diameter of the tree did not exceed ca. 5 micrometers.

Use of sol-gels as solid matrixes for simultaneous multielement determination by radio frequency glow discharge optical emission spectrometry: determinations of suspended particulate matter.

PubMed

Davis, W Clay; Knippel, Brad C; Cooper, Julia E; Spraul, Bryan K; Rice, Jeanette K; Smith, Dennis W; Marcus, R Kenneth

2003-05-15

A new approach for the analysis of particulate matter by radio frequency glow discharge optical emission spectrometry (rf-GD-OES) is described. Dispersion of the particles in a sol-gel sample matrix provides a convenient means of generating a thin film suitable for sputter-sampling into the discharge. Acid-catalyzed sol-gel glasses synthesized from tetramethyl orthosilicate were prepared and spun-cast on glass substrates. The resultant thin films on glass substrates were analyzed to determine the discharge operating conditions and resultant sputtering characteristics while a number of optical emission lines of the film components were monitored. Slurries of powdered standard reference materials NIST SRM 1884a (Portland Cement) and NIST SRM 2690 (Coal Fly Ash) dispersed in the sols were cast into films in the same manner. Use of the sol-gels as sample matrixes allows for background subtraction through the use of analytical blanks and may facilitate the generation of calibration curves via readily synthesized, matrix-matched analytical standards in solids analysis. Detection limits were determined for minor elements via the RSDB method to be in the range of 1-10 microg/g in Portland Cement and Coal Fly Ash samples for the elements Al, Fe, Mg, S, and Si. Values for Ca were in the range of 15-35 microg/g. This preliminary study demonstrates the possibility of incorporating various insoluble species, including ceramics and geological specimens in powder form, into a solid matrix for further analysis by either rf-GD-OES or MS.

Improving detection sensitivity for partial discharge monitoring of high voltage equipment

NASA Astrophysics Data System (ADS)

Hao, L.; Lewin, P. L.; Swingler, S. G.

2008-05-01

Partial discharge (PD) measurements are an important technique for assessing the health of power apparatus. Previous published research by the authors has shown that an electro-optic system can be used for PD measurement of oil-filled power transformers. A PD signal generated within an oil-filled power transformer may reach a winding and then travel along the winding to the bushing core bar. The bushing, acting like a capacitor, can transfer the high frequency components of the partial discharge signal to its earthed tap point. Therefore, an effective PD current measurement can be implemented at the bushing tap by using a radio frequency current transducer around the bushing-tap earth connection. In addition, the use of an optical transmission technique not only improves the electrical noise immunity and provides the possibility of remote measurement but also realizes electrical isolation and enhances safety for operators. However, the bushing core bar can act as an aerial and in addition noise induced by the electro-optic modulation system may influence overall measurement sensitivity. This paper reports on a machine learning technique, namely the use of a support vector machine (SVM), to improve the detection sensitivity of the system. Comparison between the signal extraction performances of a passive hardware filter and the SVM technique has been assessed. The results obtained from the laboratory-based experiment have been analysed and indicate that the SVM approach provides better performance than the passive hardware filter and it can reliably detect discharge signals with apparent charge greater than 30 pC.

Design and Preliminary Performance Testing of Electronegative Gas Plasma Thruster

NASA Technical Reports Server (NTRS)

Liu, Thomas M.; Schloeder, Natalie R.; Walker, Mitchell L. R.; Polzin, Kurt A.; Dankanich, John W.; Aanesland, Ane

2014-01-01

In classical gridded electrostatic ion thrusters, positively charged ions are generated from a plasma discharge of noble gas propellant and accelerated to provide thrust. To maintain overall charge balance on the propulsion system, a separate electron source is required to neutralize the ion beam as it exits the thruster. However, if high-electronegativity propellant gases (e.g., sulfur hexafluoride) are instead used, a plasma discharge can result consisting of both positively and negatively charged ions. Extracting such electronegative plasma species for thrust generation (e.g., with time-varying, bipolar ion optics) would eliminate the need for a separate neutralizer cathode subsystem. In addition for thrusters utilizing a RF plasma discharge, further simplification of the ion thruster power system may be possible by also using the RF power supply to bias the ion optics. Recently, the PEGASES (Plasma propulsion with Electronegative gases) thruster prototype successfully demonstrated proof-of-concept operations in alternatively accelerating positively and negatively charged ions from a RF discharge of a mixture of argon and sulfur hexafluoride.i In collaboration with NASA Marshall Space Flight Center (MSFC), the Georgia Institute of Technology High-Power Electric Propulsion Laboratory (HPEPL) is applying the lessons learned from PEGASES design and testing to develop a new thruster prototype. This prototype will incorporate design improvements and undergo gridless operational testing and diagnostics checkout at HPEPL in April 2014. Performance mapping with ion optics will be conducted at NASA MSFC starting in May 2014. The proposed paper discusses the design and preliminary performance testing of this electronegative gas plasma thruster prototype.

Formation of an optical pulsed discharge in a supersonic air flow by radiation of a repetitively pulsed CO{sub 2} laser

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

Malov, Aleksei N; Orishich, Anatolii M

Results of optimisation of repetitively pulsed CO{sub 2}-laser generation are presented for finding physical conditions of forming stable burning of an optical pulsed discharge (OPD) in a supersonic air flow and for studying the influence of pulse parameters on the energy absorption efficiency of laser radiation in plasma. The optical discharge in a supersonic air flow was formed by radiation of a repetitively pulsed CO{sub 2} laser with mechanical Q-switching excited by a discharge with a convective cooling of the working gas. For the first time the influence of radiation pulse parameters on the ignition conditions and stable burning ofmore » the OPD in a supersonic air flow was investigated and the efficiency of laser radiation absorption in plasma was studied. The influence of the air flow velocity on stability of plasma production was investigated. It was shown that stable burning of the OPD in a supersonic flow is realised at a high pulse repetition rate where the interval between radiation pulses is shorter than the time of plasma blowing-off. Study of the instantaneous value of the absorption coefficient shows that after a breakdown in a time lapse of 100 - 150 ns, a quasi-stationary 'absorption phase' is formed with the duration of {approx}1.5 ms, which exists independently of air flow and radiation pulse repetition rate. This phase of strong absorption is, seemingly, related to evolution of the ionisation wave. (laser applications and other topics in quantum electronics)« less

Water table management reduces tile nitrate loss in continuous corn and in a soybean-corn rotation.

PubMed

Drury, C F; Tan, C S; Gaynor, J D; Reynolds, W D; Welacky, T W; Oloya, T O

2001-10-25

Water table management systems can be designed to alleviate soil water excesses and deficits, as well as reduce nitrate leaching losses in tile discharge. With this in mind, a standard tile drainage (DR) system was compared over 8 years (1991 to 1999) to a controlled tile drainage/subirrigation (CDS) system on a low-slope (0.05 to 0.1%) Brookston clay loam soil (Typic Argiaquoll) in southwestern Ontario, Canada. In the CDS system, tile discharge was controlled to prevent excessive drainage, and water was pumped back up the tile lines (subirrigation) to replenish the crop root zone during water deficit periods. In the first phase of the study (1991 to 1994), continuous corn (Zea mays, L.) was grown with annual nitrogen (N) fertilizer inputs as per local soil test recommendations. In the second phase (1995 to 1999), a soybean (Glycine max L., Merr.)-corn rotation was used with N fertilizer added only during the two corn years. In Phase 1 when continuous corn was grown, CDS reduced total tile discharge by 26% and total nitrate loss in tile discharge by 55%, compared to DR. In addition, the 4-year flow weighted mean (FWM) nitrate concentration in tile discharge exceeded the Canadian drinking water guideline (10 mg N l(-1)) under DR (11.4 mg N l(-1)), but not under CDS (7.0 mg N l(-1)). In Phase 2 during the soybean-corn rotation, CDS reduced total tile discharge by 38% and total nitrate loss in tile discharge by 66%, relative to DR. The 4-year FWM nitrate concentration during Phase 2 in tile discharge was below the drinking water guideline for both DR (7.3 mg N l(-1)) and CDS (4.0 mg N l(-1)). During both phases of the experiment, the CDS treatment caused only minor increases in nitrate loss in surface runoff relative to DR. Hence CDS decreased FWM nitrate concentrations, total drainage water loss, and total nitrate loss in tile discharge relative to DR. In addition, soybean-corn rotation reduced FWM nitrate concentrations and total nitrate loss in tile discharge relative to continuous corn. CDS and crop rotations with reduced N fertilizer inputs can thus improve the quality of tile discharge water substantially.

Plasma mixing glow discharge device for analytical applications

DOEpatents

Pinnaduwage, Lal A.

1999-01-01

An instrument for analyzing a sample has an enclosure that forms a chamber containing an anode which divides the chamber into a discharge region and an analysis region. A gas inlet and outlet are provided to introduce and exhaust a rare gas into the discharge region. A cathode within the discharge region has a plurality of pins projecting in a geometric pattern toward the anode for exciting the gas and producing a plasma discharge between the cathode and the anode. Low energy electrons (e.g. <0.5 eV) pass into the analysis region through an aperture. The sample to be analyzed is placed into the analysis region and bombarded by the metastable rare gas atoms and the low energy electrons extracted into from the discharge region. A mass or optical spectrometer can be coupled to a port of the analysis region to analyze the resulting ions and light emission.

Plasma mixing glow discharge device for analytical applications

DOEpatents

Pinnaduwage, L.A.

1999-04-20

An instrument for analyzing a sample has an enclosure that forms a chamber containing an anode which divides the chamber into a discharge region and an analysis region. A gas inlet and outlet are provided to introduce and exhaust a rare gas into the discharge region. A cathode within the discharge region has a plurality of pins projecting in a geometric pattern toward the anode for exciting the gas and producing a plasma discharge between the cathode and the anode. Low energy electrons (e.g. <0.5 eV) pass into the analysis region through an aperture. The sample to be analyzed is placed into the analysis region and bombarded by the metastable rare gas atoms and the low energy electrons extracted into from the discharge region. A mass or optical spectrometer can be coupled to a port of the analysis region to analyze the resulting ions and light emission. 3 figs.

Time-resolved study of the electron temperature and number density of argon metastable atoms in argon-based dielectric barrier discharges

NASA Astrophysics Data System (ADS)

Desjardins, E.; Laurent, M.; Durocher-Jean, A.; Laroche, G.; Gherardi, N.; Naudé, N.; Stafford, L.

2018-01-01

A combination of optical emission spectroscopy and collisional-radiative modelling is used to determine the time-resolved electron temperature (assuming Maxwellian electron energy distribution function) and number density of Ar 1s states in atmospheric pressure Ar-based dielectric barrier discharges in presence of either NH3 or ethyl lactate. In both cases, T e values were higher early in the discharge cycle (around 0.8 eV), decreased down to about 0.35 eV with the rise of the discharge current, and then remained fairly constant during discharge extinction. The opposite behaviour was observed for Ar 1s states, with cycle-averaged values in the 1017 m-3 range. Based on these findings, a link was established between the discharge ionization kinetics (and thus the electron temperature) and the number density of Ar 1s state.

The cold and atmospheric-pressure air surface barrier discharge plasma for large-area sterilization applications

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

Wang Dacheng; Department of Aeronautics, Fujian Key Laboratory for Plasma and Magnetic Resonance, School of Physics and Mechanical and Electrical Engineering, Xiamen University, Xiamen, Fujian 361005; Zhao Di

2011-04-18

This letter reports a stable air surface barrier discharge device for large-area sterilization applications at room temperature. This design may result in visually uniform plasmas with the electrode area scaled up (or down) to the required size. A comparison for the survival rates of Escherichia coli from air, N{sub 2} and O{sub 2} surface barrier discharge plasmas is presented, and the air surface plasma consisting of strong filamentary discharges can efficiently kill Escherichia coli. Optical emission measurements indicate that reactive species such as O and OH generated in the room temperature air plasmas play a significant role in the sterilizationmore » process.« less

Spatiotemporal interpolation of discharge across a river network by using synthetic SWOT satellite data

NASA Astrophysics Data System (ADS)

Paiva, Rodrigo C. D.; Durand, Michael T.; Hossain, Faisal

2015-01-01

Recent efforts have sought to estimate river discharge and other surface water-related quantities using spaceborne sensors, with better spatial coverage but worse temporal sampling as compared with in situ measurements. The Surface Water and Ocean Topography (SWOT) mission will provide river discharge estimates globally from space. However, questions on how to optimally use the spatially distributed but asynchronous satellite observations to generate continuous fields still exist. This paper presents a statistical model (River Kriging-RK), for estimating discharge time series in a river network in the context of the SWOT mission. RK uses discharge estimates at different locations and times to produce a continuous field using spatiotemporal kriging. A key component of RK is the space-time river discharge covariance, which was derived analytically from the diffusive wave approximation of Saint Venant's equations. The RK covariance also accounts for the loss of correlation at confluences. The model performed well in a case study on Ganges-Brahmaputra-Meghna (GBM) River system in Bangladesh using synthetic SWOT observations. The correlation model reproduced empirically derived values. RK (R2=0.83) outperformed other kriging-based methods (R2=0.80), as well as a simple time series linear interpolation (R2=0.72). RK was used to combine discharge from SWOT and in situ observations, improving estimates when the latter is included (R2=0.91). The proposed statistical concepts may eventually provide a feasible framework to estimate continuous discharge time series across a river network based on SWOT data, other altimetry missions, and/or in situ data.

46 CFR 108.453 - Discharge outlets.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Discharge outlets. 108.453 Section 108.453 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.453 Discharge...

46 CFR 108.453 - Discharge outlets.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Discharge outlets. 108.453 Section 108.453 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.453 Discharge...

32 CFR 724.201 - Authority.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Authority. 724.201 Section 724.201 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Authority/Policy for Departmental Discharge Review § 724.201 Authority. The Naval Discharge Review Board...

Micro hollow cathode discharge jets utilizing solid fuel

NASA Astrophysics Data System (ADS)

Nikic, Dejan

2017-10-01

Micro hollow cathode discharge devices with a solid fuel layer embedded between the electrodes have demonstrated an enhanced jetting process. Outlined are series of experiments in various pressure and gas conditions as well as vacuum. Examples of use of these devices in series and parallel configurations are presented. Evidence of utilization of solid fuel is obtained through optical spectroscopy and analysis of remaining fuel layer.

Photonic surgery with noncoherent light

NASA Astrophysics Data System (ADS)

Feuermann, Daniel; Gordon, Jeffrey M.; Ng, Tuck Wah

2006-03-01

Extensive photothermal surgical effects have been generated with artificial noncoherent light. Our ex vivo experiments produced the same type and extent of tissue damage ordinarily achieved with laser fiber-optic surgery, at comparable surgical efficacy, the motivation being the possibility of supplanting surgical lasers with a potentially far less expensive device. Maximum-flux optics reconstitute the immense power density at the core of an ultrabright discharge lamp inside an optical fiber the distal tip of which couples light into the organ.

46 CFR 193.15-25 - Discharge outlets.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Discharge outlets. 193.15-25 Section 193.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-25 Discharge outlets. (a...

46 CFR 193.15-25 - Discharge outlets.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Discharge outlets. 193.15-25 Section 193.15-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-25 Discharge outlets. (a...

Optical and structural properties of carbon dots/TiO2 nanostructures prepared via DC arc discharge in liquid

NASA Astrophysics Data System (ADS)

Biazar, Nooshin; Poursalehi, Reza; Delavari, Hamid

2018-01-01

Synthesis and development of visible active catalysts is an important issue in photocatalytic applications of nanomaterials. TiO2 nanostructures coupled with carbon dots demonstrate a considerable photocatalytic activity in visible wavelengths. Extending optical absorption of a wide band gap semiconductor such as TiO2 with carbon dots is the origin of the visible activity of carbon dots modified semiconductor nanostructures. In addition, carbon dots exhibit high photostability, appropriate electron transport and chemical stability without considerable toxicity or environmental footprints. In this study, optical and structural properties of carbon dots/TiO2 nanostructures prepared via (direct current) DC arc discharge in liquid were investigated. Crystal structure, morphology and optical properties of the samples were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-visible spectroscopy respectively. SEM images show formation of spherical nanoparticles with an average size of 27 nm. In comparison with pristine TiO2, optical transmission spectrum of carbon dots/TiO2 nanostructures demonstrates an absorption edge at longer wavelengths as well a high optical absorption in visible wavelengths which is significant for visible activity of nanostructures as a photocatalyst. Finally, these results can provide a flexible and versatile pathway for synthesis of carbon dots/oxide semiconductor nanostructures with an appropriate activity under visible light.

Preliminary design study of astronomical detector cooling system

NASA Technical Reports Server (NTRS)

Norman, R. H.

1976-01-01

The preliminary design of an astronomical detector cooling system for possible use in the NASA C-141 Airborne Infrared Observatory is presented. The system consists of the following elements: supercritical helium tank, Joule-Thomson supply gas conditioner, Joule-Thomson expander (JTX), optical cavity dewar, optical cavity temperature controller, adjustable J-T discharge gas pressure controller, and vacuum pump.

The research on a novel type of the solar-blind UV head-mounted displays

NASA Astrophysics Data System (ADS)

Zhao, Shun-long

2011-08-01

Ultraviolet technology of detecting is playing a more and more important role in the field of civil application, especially in the corona discharge detection, in modern society. Now the UV imaging detector is one of the most important equipments in power equipment flaws detection. And the modern head-mounted displays (HMDs) have shown the applications in the fields of military, industry production, medical treatment, entertainment, 3D visualization, education and training. We applied the system of head-mounted displays to the UV image detection, and a novel type of head-mounted displays is presented: the solar-blind UV head-mounted displays. And the structure is given. By the solar-blind UV head-mounted displays, a real-time, isometric and visible image of the corona discharge is correctly displayed upon the background scene where it exists. The user will see the visible image of the corona discharge on the real scene rather than on a small screen. Then the user can easily find out the power equipment flaws and repair them. Compared with the traditional UV imaging detector, the introducing of the HMDs simplifies the structure of the whole system. The original visible spectrum optical system is replaced by the eye in the solar-blind UV head-mounted displays. And the optical image fusion technology would be used rather than the digital image fusion system which is necessary in traditional UV imaging detector. That means the visible spectrum optical system and digital image fusion system are not necessary. This makes the whole system cheaper than the traditional UV imaging detector. Another advantage of the solar-blind UV head-mounted displays is that the two hands of user will be free. So while observing the corona discharge the user can do some things about it. Therefore the solar-blind UV head-mounted displays can make the corona discharge expose itself to the user in a better way, and it will play an important role in corona detection in the future.

Depth elemental characterization of 1D self-aligned TiO2 nanotubes using calibrated radio frequency glow discharge optical emission spectroscopy (GDOES)

NASA Astrophysics Data System (ADS)

Mohajernia, Shiva; Mazare, Anca; Hwang, Imgon; Gaiaschi, Sofia; Chapon, Patrick; Hildebrand, Helga; Schmuki, Patrik

2018-06-01

In this work we study the depth composition of anodic TiO2 nanotube layers. We use elemental depth profiling with Glow Discharge Optical Emission Spectroscopy and calibrate the results of this technique with X-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS). We establish optimized sputtering conditions for nanotubular structures using the pulsed RF mode, which causes minimized structural damage during the depth profiling of the nanotubular structures. This allows to obtain calibrated sputter rates that account for the nanotubular "porous" morphology. Most importantly, sputter-artifact free compositional profiles of these high aspect ratio 3D structures are obtained, as well as, in combination with SEM, elegant depth sectional imaging.

Calculating mercury loading to the tidal Hudson River, New York, using rating curve and surrogate methodologies

USGS Publications Warehouse

Wall, G.R.; Ingleston, H.H.; Litten, S.

2005-01-01

Total mercury (THg) load in rivers is often calculated from a site-specific "rating-curve" based on the relation between THg concentration and river discharge along with a continuous record of river discharge. However, there is no physical explanation as to why river discharge should consistently predict THg or any other suspended analyte. THg loads calculated by the rating-curve method were compared with those calculated by a "continuous surrogate concentration" (CSC) method in which a relation between THg concentration and suspended-sediment concentration (SSC) is constructed; THg loads then can be calculated from the continuous record of SSC and river discharge. The rating-curve and CSC methods, respectively, indicated annual THg loads of 46.4 and 75.1 kg for the Mohawk River, and 52.9 and 33.1 kg for the upper Hudson River. Differences between the results of the two methods are attributed to the inability of the rating-curve method to adequately characterize atypical high flows such as an ice-dam release, or to account for hysteresis, which typically degrades the strength of the relation between stream discharge and concentration of material in suspension. ?? Springer 2005.

Temporal Dynamics in the Concentration, Flux, and Optical Properties of Tree-Derived Dissolved Organic Matter in an Epiphyte-Laden Oak-Cedar Forest

NASA Astrophysics Data System (ADS)

Van Stan, John T.; Wagner, Sasha; Guillemette, François; Whitetree, Ansley; Lewis, Julius; Silva, Leticia; Stubbins, Aron

2017-11-01

Studies on the fate and transport of dissolved organic matter (DOM) along the rainfall-to-discharge flow pathway typically begin in streams or soils, neglecting the initial enrichment of rainfall with DOM during contact with plant canopies. However, rain water can gather significant amounts of tree-derived DOM (tree-DOM) when it drains from the canopy, as throughfall, and down the stem, as stemflow. We examined the temporal variability of event-scale tree-DOM concentrations, yield, and optical (light absorbance and fluorescence) characteristics from an epiphyte-laden Quercus virginiana-Juniperus virginiana forest on Skidaway Island, Savannah, Georgia (USA). All tree-DOM fluxes were highly enriched in dissolved organic carbon (DOC) compared to rainfall, and epiphytes further increased concentrations. Stemflow DOC concentrations were greater than throughfall across study species, yet larger throughfall water yields produced greater DOC yields versus stemflow. Tree-DOM optical characteristics indicate it is aromatic-rich with fluorescent DOM dominated by humic-like fluorescence, containing 10-20% protein-like (tryptophan-like) fluorescence. Storm size was the only storm condition that strongly correlated with tree-DOM concentration and flux; however, throughfall and stemflow optical characteristics varied little across a wide range of storm conditions (from low magnitude events to intense tropical storms). Annual tree-DOM yields from the study forest (0.8-46 g C m-2 yr-1) were similar to other yields from discrete down-gradient fluxes (litter leachates, soil leachates, and stream discharge) along the rainfall-to-discharge flow path.

40 CFR 110.3 - Discharge of oil in such quantities as “may be harmful” pursuant to section 311(b)(4) of the Act.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 22 2011-07-01 2011-07-01 false Discharge of oil in such quantities as... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS DISCHARGE OF OIL § 110.3 Discharge of... may be harmful to the public health or welfare or the environment of the United States include...

40 CFR 110.3 - Discharge of oil in such quantities as “may be harmful” pursuant to section 311(b)(4) of the Act.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 23 2012-07-01 2012-07-01 false Discharge of oil in such quantities as... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS DISCHARGE OF OIL § 110.3 Discharge of... may be harmful to the public health or welfare or the environment of the United States include...

40 CFR 110.3 - Discharge of oil in such quantities as “may be harmful” pursuant to section 311(b)(4) of the Act.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Discharge of oil in such quantities as... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS DISCHARGE OF OIL § 110.3 Discharge of... may be harmful to the public health or welfare or the environment of the United States include...

VizieR Online Data Catalog: Gas-phase detection of c-C3H3

NASA Astrophysics Data System (ADS)

Zhao, D.; Doney, K. D.; Linnartz, H.

2017-03-01

The experimental setup has been described in detail by Zhao et al. (2013CPL...565..132Z, 2014JMoSp.296....1Z). In brief, the c-C3H3+ cations are generated by discharging a propyne (C3H4):He ~ 1:200 gas mixture in a multi-layer slit discharge nozzle (Motylewski & Linnartz 1999RScI...70.1305M) in combination with a pulsed valve (General Valve, Series 9,2 mm orifice). The gas mixture is expanded with a backing pressure of ~7 bar through a 300umx3cm slit into a vacuum chamber. A pulsed negative high voltage (-600 V/300 mA) with a ~600 us duration is found to be optimum for c-C3H3+ production, is applied to the expanding gas mixture, and is set to coincide with the expanding gas pulse (~800 us). Continuous-wave cavity ring-down spectroscopy (cw-CRDS) is used to record spectra in direct absorption. The axis of the optical cavity is aligned parallel to and ~2 mm downstream of the slit nozzle throat. A single-mode cw optical parametric oscillator (Aculight), operating at ~3.15 um with a bandwidth <5x10-5cm-1, is employed as tunable IR light source. A hardware-based (boxcar integrator) multi-trigger and timing scheme recently reported by Zhao et al. (2013CPL...565..132Z) is used to apply cw-CRDS to the pulsed plasma. In the present experiment, typical ring-down time values are ~8-10 us, corresponding to a detection sensitivity, i.e., noise equivalent absorption, of up to ~2x10-7 per centimeter for the 3 cm long plasma jet. (1 data file).

Characterizing submarine ground‐water discharge using fiber‐optic distributed temperature sensing and marine electrical resistivity

USGS Publications Warehouse

Henderson, Rory; Day-Lewis, Frederick D.; Lane, John W.; Harvey, Charles F.; Liu, Lanbo

2008-01-01

Submarine ground‐water discharge (SGD) contributes important solute fluxes to coastal waters. Pollutants are transported to coastal ecosystems by SGD at spatially and temporally variable rates. New approaches are needed to characterize the effects of storm‐event, tidal, and seasonal forcing on SGD. Here, we evaluate the utility of two geophysical methods‐fiber‐optic distributed temperature sensing (FO‐DTS) and marine electrical resistivity (MER)—for observing the spatial and temporal variations in SGD and the configuration of the freshwater/saltwater interface within submarine sediments. FO‐DTS and MER cables were permanently installed into the estuary floor on a transect extending 50 meters offshore under Waquoit Bay, Massachusetts, at the Waquoit Bay National Estuarine Research Reserve, and nearly continuous data were collected for 4 weeks in summer 2007. Initial results indicate that the methods are extremely useful for monitoring changes in the complex estuarine environment. The FO‐DTS produced time‐series data at approximately 1‐meter increments along the length of the fiber at approximately 29‐second intervals. The temperature time‐series data show that the temperature at near‐shore locations appears to be dominated by a semi‐diurnal (tidal) signal, whereas the temperature at off‐shore locations is dominated by a diurnal signal (day/night heating and cooling). Dipole‐dipole MER surveys were completed about every 50 minutes, allowing for production of high‐resolution time‐lapse tomograms, which provide insight into the variations of the subsurface freshwater/saltwater interface. Preliminary results from the MER data show a high‐resistivity zone near the shore at low tide, indicative of SGD, and consistent with the FO‐DTS results.

32 CFR 724.903 - Equity of the discharge.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Equity of the discharge. 724.903 Section 724.903 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW... factors such as: (i) Service history, including date of enlistment, period of enlistment, highest rank...

32 CFR 724.903 - Equity of the discharge.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Equity of the discharge. 724.903 Section 724.903 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW... factors such as: (i) Service history, including date of enlistment, period of enlistment, highest rank...

32 CFR 724.903 - Equity of the discharge.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 5 2012-07-01 2012-07-01 false Equity of the discharge. 724.903 Section 724.903 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW... factors such as: (i) Service history, including date of enlistment, period of enlistment, highest rank...

32 CFR 724.903 - Equity of the discharge.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 5 2013-07-01 2013-07-01 false Equity of the discharge. 724.903 Section 724.903 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW... factors such as: (i) Service history, including date of enlistment, period of enlistment, highest rank...

38 CFR 52.80 - Enrollment, transfer and discharge rights.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) PER DIEM FOR ADULT DAY HEALTH CARE OF VETERANS IN STATE HOMES Standards § 52.80 Enrollment, transfer and discharge rights. (a) Participants in the adult day health care program must meet the...) Diagnosis of clinical depression. (vi) Recent discharge from nursing home or hospital. (vii) Significant...

21 CFR 1250.93 - Discharge of wastes.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Discharge of wastes. 1250.93 Section 1250.93 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.93 Discharge of wastes. Vessels operating...

40 CFR 125.67 - Increase in effluent volume or amount of pollutants discharged.

Code of Federal Regulations, 2011 CFR

2011-07-01

... AGENCY (CONTINUED) WATER PROGRAMS CRITERIA AND STANDARDS FOR THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM Criteria for Modifying the Secondary Treatment Requirements Under Section 301(h) of the Clean Water Act § 125.67 Increase in effluent volume or amount of pollutants discharged. (a) No modified...

40 CFR 125.67 - Increase in effluent volume or amount of pollutants discharged.

Code of Federal Regulations, 2010 CFR

2010-07-01

... AGENCY (CONTINUED) WATER PROGRAMS CRITERIA AND STANDARDS FOR THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM Criteria for Modifying the Secondary Treatment Requirements Under Section 301(h) of the Clean Water Act § 125.67 Increase in effluent volume or amount of pollutants discharged. (a) No modified...

21 CFR 1250.93 - Discharge of wastes.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Discharge of wastes. 1250.93 Section 1250.93 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.93 Discharge of wastes. Vessels operating...

The Influence of Gas Composition in Dielectric Barrier Discharges on the Broadening of the Hydrogen H{alpha} Transition

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

Janus, H. W.

The distribution of hydrogen atoms responsible for emission of the Balmer H{alpha} line in the region of the dielectric barrier discharges in the helium and hydrogen as well as in the argon and hydrogen mixtures, in the direction perpendicular to the electrode surfaces, has bee determined by the optical emission spectroscopy accounting for the polarization of the emitted light. The procedure of fitting the measured line profiles accounting for the Stark effect has been used for determination of the distribution of the electric field in the discharge region.

Elves and associated electron density changes due to cloud-to-ground and in-cloud lightning discharges

NASA Astrophysics Data System (ADS)

Marshall, R. A.; Inan, U. S.; Glukhov, V. S.

2010-04-01

A 3-D finite difference time domain model is used to simulate the lightning electromagnetic pulse (EMP) and its interaction with the lower ionosphere. Results agree with the frequently observed, doughnut-shaped optical signature of elves but show that the structure exhibits asymmetry due to the presence of Earth's ambient magnetic field. Furthermore, in-cloud (horizontal) lightning channels produce observable optical emissions without the doughnut shape and, in fact, produce a much stronger optical output for the same channel current. Electron density perturbations associated with elves are also calculated, with contributions from attachment and ionization. Results presented as a function of parameters such as magnetic field direction, dipole current orientation, altitude and amplitude, and ambient ionospheric density profile demonstrate the highly nonlinear nature of the EMP-ionosphere interaction. Ionospheric effects of a sequence of in-cloud discharges are calculated, simulating a burst of in-cloud lightning activity and resulting in large density changes in the overlying ionosphere.

All-optical temporal fractional order differentiator using an in-fiber ellipsoidal air-microcavity

NASA Astrophysics Data System (ADS)

Zhang, Lihong; Sun, Shuqian; Li, Ming; Zhu, Ninghua

2017-12-01

An all-optical temporal fractional order differentiator with ultrabroad bandwidth (~1.6 THz) and extremely simple fabrication is proposed and experimentally demonstrated based on an in-fiber ellipsoidal air-microcavity. The ellipsoidal air-microcavity is fabricated by splicing a single mode fiber (SMF) and a photonic crystal fiber (PCF) together using a simple arc-discharging technology. By changing the arc-discharging times, the propagation loss can be adjusted and then the differentiation order is tuned. A nearly Gaussian-like optical pulse with 3 dB bandwidth of 8 nm is launched into the differentiator and a 0.65 order differentiation of the input pulse is achieved with a processing error of 2.55%. Project supported by the the National Natural Science Foundation of China (Nos. 61522509, 61377002, 61535012), the National High-Tech Research & Development Program of China (No. SS2015AA011002), and the Beijing Natural Science Foundation (No. 4152052). Ming Li was supported in part by the Thousand Young Talent Program.

Advanced MRI in Acute Military TBI

DTIC Science & Technology

2014-09-01

symptoms onmental health and service discharge outcomes. J Neurotrauma. 2013; 30(16):1391-1397. 16. GalarneauMR,Woodruff SI, Dye JL, Mohrle CR, Wade...related mild traumatic brain injury acute symptoms on mental health and service discharge outcomes. J. Neurotrauma 30, 1391–1397. 22. Casscells, S. (2007...radiation (include optic radiation) left 37 Anterior corona radiata right 102 Anterior corona radiata left 38 Superior corona radiata right 103 Superior

Characteristics of molecular hydrogen and CH* radicals in a methane plasma in a magnetically enhanced capacitive RF discharge

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

Avtaeva, S. V.; Lapochkina, T. M.

2007-09-15

The parameters of a methane-containing plasma in an asymmetric RF capacitive discharge in an external magnetic field were studied using optical emission spectroscopy. The power deposited in the discharge was 90 W and the gas pressure and magnetic field were varied in the ranges 1-5 Pa and 50-200 G, respectively. The vibrational and rotational temperatures of hydrogen molecules and CH* radicals were measured as functions of the magnetic field and methane pressure. The ratio between the densities of atomic and molecular hydrogen was estimated. The processes responsible for the excitation of molecular hydrogen and CH* radicals in a methane-containing plasmamore » in an RF capacitive discharge are analyzed.« less

Study of a rare-gas transverse fast discharge

NASA Technical Reports Server (NTRS)

Chubb, D. L.; Michels, C. J.

1979-01-01

An experimental and analytical study of a Blumlein-type transverse fast discharge operating with He and Xe are presented. An electro-optical voltage probe was used to measure the discharge voltage, and the measured voltages were in agreement with the computed voltages. The analytical model was used to predict the dependence of the discharge efficiency for producing metastables and ions on the important plasma and external circuit parameters. In He the ion efficiency is greater than the metastable efficiency, while in Xe it is the opposite; the He ion efficiencies are much larger than in Xe, while Xe metastable efficiencies are much larger than in He. These differences between Xe and He are accounted by the large dissociative recombination rate of Xe compared with He.

Investigation Of The High-Voltage Discharge On The Surface Of Gas-Liquid System

NASA Astrophysics Data System (ADS)

Nguyen-Kuok, Shi; Morgunov, Aleksandr; Malakhov, Yury; Korotkikh, Ivan

2016-09-01

This paper describes an experimental setup for study of physical processes in the high-voltage discharge on the surface of gas-liquid system at atmospheric pressure. Measurements of electrical and optical characteristics of the high-voltage discharge in gas, at the surface of the gas-liquid system and in the electrolyte are obtained. The parameters of the high-voltage discharge and the conditions for its stable operation are presented. Investigations with various electrolytes and cathode assemblies of various materials and sizes were carried out. The installation can be used for the processing and recycling of industrial and chemical liquid waste. Professor of Laboratory of Plasma Physics, National Research University MPEI, Krasnokazarmennya Str.14, 111250, Moscow, Russia.

Spectral Characteristics of Deuterium-, Helium- and Gas-Mixture-Discharges within PF-1000 Facility

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

Tsarenko, A.; Malinowski, K.; Skladnik-Sadowska, E.

2006-01-15

The paper reports on spectroscopic studies of high-current plasma discharges performed at different gas fillings within the large PF-1000 facility. To study visible radiation (VR) the use was made of a MECHELLE registered 900-spectrometer equipped with the CCD readout. The observations of a PF pinch column were performed at an angle of about 65 deg. to the z-axis, and the viewing field was at a distance of 40-50 mm from the electrode ends. Optical measurements were carried out at 0.5-{mu}s exposition synchronized with a chosen period of the investigated discharge. Differences in the optical spectra, recorded at various deuterium-helium mixtures,more » were analyzed. Intensities of HeI lines were computed for an assumed electron temperature and compared with the experiment. Estimated plasma concentration in pure-deuterium discharges amounted to 8x1018 cm-3, while that in pure helium shots was (4-7)x1017 cm-3 only. Estimates of the electron temperature, from the ratio of intensities of the chosen spectral lines and the continuum, gave values ranging from 5 eV to 50 eV. The paper presents also some spectra from 'weak shots', which show distinct impurity lines caused by different reasons.« less

Cambridge community Optometry Glaucoma Scheme.

PubMed

Keenan, Jonathan; Shahid, Humma; Bourne, Rupert R; White, Andrew J; Martin, Keith R

2015-04-01

With a higher life expectancy, there is an increased demand for hospital glaucoma services in the United Kingdom. The Cambridge community Optometry Glaucoma Scheme (COGS) was initiated in 2010, where new referrals for suspected glaucoma are evaluated by community optometrists with a special interest in glaucoma, with virtual electronic review and validation by a consultant ophthalmologist with special interest in glaucoma. 1733 patients were evaluated by this scheme between 2010 and 2013. Clinical assessment is performed by the optometrist at a remote site. Goldmann applanation tonometry, pachymetry, monoscopic colour optic disc photographs and automated Humphrey visual field testing are performed. A clinical decision is made as to whether a patient has glaucoma or is a suspect, and referred on or discharged as a false positive referral. The clinical findings, optic disc photographs and visual field test results are transmitted electronically for virtual review by a consultant ophthalmologist. The number of false positive referrals from initial referral into the scheme. Of the patients, 46.6% were discharged at assessment and a further 5.7% were discharged following virtual review. Of the patients initially discharged, 2.8% were recalled following virtual review. Following assessment at the hospital, a further 10.5% were discharged after a single visit. The COGS community-based glaucoma screening programme is a safe and effective way of evaluating glaucoma referrals in the community and reducing false-positive referrals for glaucoma into the hospital system. © 2014 Royal Australian and New Zealand College of Ophthalmologists.

[Study on the discharge properties of xeon flash lamp and experimental measurement].

PubMed

Zhao, You-Quan; Miao, Pei-Liang; He, Feng; Gu, Jian; Zhai, Rui-Wei

2014-07-01

The Xenon flash lamp is a new type of light source for analytical instrument. The present paper analyzed the discharge process of xenon flash lamp, presented the discharge test system, and conducted experimental measurement of the voltage, current and optical pulse signal in the process of discharge. The results show that in the preliminary discharge, the free electron concentration was at a low level, so the energy was at a low level, then following the gas discharge, numerous free electrons formed in the lamp, resultin in the increase in the concentration of free electrons, therefore discharge current rised rapidly and voltage reduced. The lamp released photons to generate light pulse in the moment of ionic recombination, The pulse xenon lamp light energy output and spectral characteristic is related to electron energy in recombination and combination level of xenon, if the input energy and the energy consumption of the xenon lamp is inconsistent, it will lead to repeated capacitor charging and discharging and produce oscillation waveform. This paper is very useful for understanding the process of xenon lamp discharge, optimizing the driver circuit and the production of xenon flash lamp.

40 CFR 110.5 - Discharges of oil not determined “as may be harmful” pursuant to Section 311(b)(3) of the Act.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Discharges of oil not determined âas may be harmfulâ pursuant to Section 311(b)(3) of the Act. 110.5 Section 110.5 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS DISCHARGE OF OIL § 110.5 Discharges of...

40 CFR 110.3 - Discharge of oil in such quantities as “may be harmful” pursuant to section 311(b)(4) of the Act.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 23 2013-07-01 2013-07-01 false Discharge of oil in such quantities as... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS DISCHARGE OF OIL § 110.3 Discharge of oil in such quantities as “may be harmful” pursuant to section 311(b)(4) of the Act. For purposes of...

40 CFR 110.3 - Discharge of oil in such quantities as “may be harmful” pursuant to section 311(b)(4) of the Act.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 22 2014-07-01 2013-07-01 true Discharge of oil in such quantities as... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS DISCHARGE OF OIL § 110.3 Discharge of oil in such quantities as “may be harmful” pursuant to section 311(b)(4) of the Act. For purposes of...

Continuous estimation of baseflow in snowmelt-dominated streams and rivers in the Upper Colorado River Basin: A chemical hydrograph separation approach

USGS Publications Warehouse

Miller, Matthew P.; Susong, David D.; Shope, Christopher L.; Heilweil, Victor M.; Stolp, Bernard J.

2014-01-01

Effective science-based management of water resources in large basins requires a qualitative understanding of hydrologic conditions and quantitative measures of the various components of the water budget, including difficult to measure components such as baseflow discharge to streams. Using widely available discharge and continuously collected specific conductance (SC) data, we adapted and applied a long established chemical hydrograph separation approach to quantify daily and representative annual baseflow discharge at fourteen streams and rivers at large spatial (> 1,000 km2 watersheds) and temporal (up to 37 years) scales in the Upper Colorado River Basin. On average, annual baseflow was 21-58% of annual stream discharge, 13-45% of discharge during snowmelt, and 40-86% of discharge during low-flow conditions. Results suggest that reservoirs may act to store baseflow discharged to the stream during snowmelt and release that baseflow during low-flow conditions, and that irrigation return flows may contribute to increases in fall baseflow in heavily irrigated watersheds. The chemical hydrograph separation approach, and associated conceptual model defined here provide a basis for the identification of land use, management, and climate effects on baseflow.

Effect of Fe{sub 3}O{sub 4} nanoparticles on space charge distribution in propylene carbonate under impulse voltage

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

Sima, Wenxia, E-mail: cqsmwx@cqu.edu.cn; Song, He; Yang, Qing

2015-12-15

Addition of nanoparticles of the ferromagnetic material Fe{sub 3}O{sub 4} can increase the positive impulse breakdown voltage of propylene carbonate by 11.65%. To further investigate the effect of ferromagnetic nanoparticles on the space charge distribution in the discharge process, the present work set up a Kerr electro-optic field mapping measurement system using an array photodetector to carry out time-continuous measurement of the electric field and space charge distribution in propylene carbonate before and after modification. Test results show that fast electrons can be captured by Fe{sub 3}O{sub 4} nanoparticles and converted into relatively slow, negatively charged particles, inhibiting the generationmore » and transportation of the space charge, especially the negative space charge.« less

Miniaturized photoacoustic spectrometer

DOEpatents

Okandan, Murat; Robinson, Alex; Nielson, Gregory N.; Resnick, Paul J.

2016-08-09

A low-power miniaturized photoacoustic sensor uses an optical microphone made by semiconductor fabrication techniques, and optionally allows for all-optical communication to and from the sensor. This allows integration of the photoacoustic sensor into systems with special requirements, such as those that would be reactive in an electrical discharge condition. The photoacoustic sensor can also be operated in various other modes with wide application flexibility.

40 CFR Table 5 to Part 455 - BAT and NSPS Effluent Limitations for Priority Pollutants for Direct Discharge Point Sources That...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 30 2014-07-01 2014-07-01 false BAT and NSPS Effluent Limitations for Priority Pollutants for Direct Discharge Point Sources That Do Not Use End-of-Pipe Biological Treatment 5 Table 5 to Part 455 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED)...

40 CFR Table 5 to Part 455 - BAT and NSPS Effluent Limitations for Priority Pollutants for Direct Discharge Point Sources That...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 31 2012-07-01 2012-07-01 false BAT and NSPS Effluent Limitations for Priority Pollutants for Direct Discharge Point Sources That Do Not Use End-of-Pipe Biological Treatment 5 Table 5 to Part 455 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED)...

40 CFR Table 5 to Part 455 - BAT and NSPS Effluent Limitations for Priority Pollutants for Direct Discharge Point Sources That...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 31 2013-07-01 2013-07-01 false BAT and NSPS Effluent Limitations for Priority Pollutants for Direct Discharge Point Sources That Do Not Use End-of-Pipe Biological Treatment 5 Table 5 to Part 455 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED)...

40 CFR 430.25 - New source performance standards (NSPS).

Code of Federal Regulations, 2014 CFR

2014-07-01

... the discharger certifies to the permitting authority that it is not using these compounds as biocides. Also, for non-continuous dischargers, concentration limitations (mg/l) shall apply. Concentration...

40 CFR 430.25 - New source performance standards (NSPS).

Code of Federal Regulations, 2011 CFR

2011-07-01

... the discharger certifies to the permitting authority that it is not using these compounds as biocides. Also, for non-continuous dischargers, concentration limitations (mg/l) shall apply. Concentration...

40 CFR 430.25 - New source performance standards (NSPS).

Code of Federal Regulations, 2010 CFR

2010-07-01

... the discharger certifies to the permitting authority that it is not using these compounds as biocides. Also, for non-continuous dischargers, concentration limitations (mg/l) shall apply. Concentration...

40 CFR 430.25 - New source performance standards (NSPS).

Code of Federal Regulations, 2013 CFR

2013-07-01

... the discharger certifies to the permitting authority that it is not using these compounds as biocides. Also, for non-continuous dischargers, concentration limitations (mg/l) shall apply. Concentration...

40 CFR 430.25 - New source performance standards (NSPS).

Code of Federal Regulations, 2012 CFR

2012-07-01

... the discharger certifies to the permitting authority that it is not using these compounds as biocides. Also, for non-continuous dischargers, concentration limitations (mg/l) shall apply. Concentration...

CFD analysis on gas distribution for different scrubber redirection configurations in sump cut.

PubMed

Zheng, Y; Organiscak, J A; Zhou, L; Beck, T W; Rider, J P

2015-01-01

The National Institute for Occupational Safety and Health's Office of Mine Safety and Health Research recently developed a series of models using computational fluid dynamics (CFD) to study the gas distribution around a continuous mining machine with various fan-powered flooded bed scrubber discharge configurations. CFD models using Species Transport Model without reactions in FLUENT were constructed to evaluate the redirection of scrubber discharge toward the mining face rather than behind the return curtain. The following scenarios are considered in this study: 100 percent of the discharge redirected back toward the face on the off-curtain side of the continuous miner; 100 percent of the discharge redirected back toward the face, but divided equally to both sides of the machine; and 15 percent of the discharge redirected toward the face on the off-curtain side of the machine, with 85 percent directed into the return. These models were compared against a model with a conventional scrubber discharge, where air is directed away from the face into the return. The CFD models were calibrated and validated based on experimental data and accurately predicted sulfur hexafluoride (SF 6 ) gas levels at four gas monitoring locations. One additional prediction model was simulated to consider a different scrubber discharge angle for the 100 percent redirected, equally divided case. These models identified relatively high gassy areas around the continuous miner, which may not warrant their use in coal mines with medium to high methane liberation rates. This paper describes the methodology used to develop the CFD models, and the validation of the models based on experimental data.

Statistical models for sediment/detritus and dissolved absorption coefficients in coastal waters of the northern Gulf of Mexico

NASA Astrophysics Data System (ADS)

Green, Rebecca E.; Gould, Richard W., Jr.; Ko, Dong S.

2008-06-01

We developed statistically-based, optical models to estimate tripton (sediment/detrital) and colored dissolved organic matter (CDOM) absorption coefficients ( a sd, a g) from physical hydrographic and atmospheric properties. The models were developed for northern Gulf of Mexico shelf waters using multi-year satellite and physical data. First, empirical algorithms for satellite-derived a sd and a g were developed, based on comparison with a large data set of cruise measurements from northern Gulf shelf waters; these algorithms were then applied to a time series of ocean color (SeaWiFS) satellite imagery for 2002-2005. Unique seasonal timing was observed in satellite-derived optical properties, with a sd peaking most often in fall/winter on the shelf, in contrast to summertime peaks observed in a g. Next, the satellite-derived values were coupled with the physical data to form multiple regression models. A suite of physical forcing variables were tested for inclusion in the models: discharge from the Mississippi River and Mobile Bay, Alabama; gridded fields for winds, precipitation, solar radiation, sea surface temperature and height (SST, SSH); and modeled surface salinity and currents (Navy Coastal Ocean Model, NCOM). For satellite-derived a sd and a g time series (2002-2004), correlation and stepwise regression analyses revealed the most important physical forcing variables. Over our region of interest, the best predictors of tripton absorption were wind speed, river discharge, and SST, whereas dissolved absorption was best predicted by east-west wind speed, river discharge, and river discharge lagged by 1 month. These results suggest the importance of vertical mixing (as a function of winds and thermal stratification) in controlling a sd distribution patterns over large regions of the shelf, in comparison to advection as the most important control on a g. The multiple linear regression models for estimating a sd and a g were applied on a pixel-by-pixel basis and results were compared to monthly SeaWiFS composite imagery. The models performed well in resolving seasonal and interannual optical variability in model development years (2002-2004) (mean error of 32% for a sd and 29% for a g) and in predicting shelfwide optical patterns in a year independent of model development (2005; mean error of 41% for a sd and 46% for a g). The models provide insight into the dominant processes controlling optical distributions in this region, and they can be used to predict the optical fields from the physical properties at monthly timescales.

40 CFR 122.28 - General permits (applicable to State NPDES programs, see § 123.25).

Code of Federal Regulations, 2010 CFR

2010-07-01

... operations; (B) Discharge the same types of wastes or engage in the same types of sludge use or disposal... AGENCY (CONTINUED) WATER PROGRAMS EPA ADMINISTERED PERMIT PROGRAMS: THE NATIONAL POLLUTANT DISCHARGE... or subcategories of discharges or sludge use or disposal practices or facilities described in the...

40 CFR 125.64 - Effect of the discharge on other point and nonpoint sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 23 2012-07-01 2012-07-01 false Effect of the discharge on other point... (CONTINUED) WATER PROGRAMS CRITERIA AND STANDARDS FOR THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM Criteria for Modifying the Secondary Treatment Requirements Under Section 301(h) of the Clean Water Act...

40 CFR 125.64 - Effect of the discharge on other point and nonpoint sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Effect of the discharge on other point... (CONTINUED) WATER PROGRAMS CRITERIA AND STANDARDS FOR THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM Criteria for Modifying the Secondary Treatment Requirements Under Section 301(h) of the Clean Water Act...

40 CFR 125.64 - Effect of the discharge on other point and nonpoint sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 22 2014-07-01 2013-07-01 true Effect of the discharge on other point... (CONTINUED) WATER PROGRAMS CRITERIA AND STANDARDS FOR THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM Criteria for Modifying the Secondary Treatment Requirements Under Section 301(h) of the Clean Water Act...

40 CFR 125.64 - Effect of the discharge on other point and nonpoint sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 22 2011-07-01 2011-07-01 false Effect of the discharge on other point... (CONTINUED) WATER PROGRAMS CRITERIA AND STANDARDS FOR THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM Criteria for Modifying the Secondary Treatment Requirements Under Section 301(h) of the Clean Water Act...

40 CFR 125.64 - Effect of the discharge on other point and nonpoint sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 23 2013-07-01 2013-07-01 false Effect of the discharge on other point... (CONTINUED) WATER PROGRAMS CRITERIA AND STANDARDS FOR THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM Criteria for Modifying the Secondary Treatment Requirements Under Section 301(h) of the Clean Water Act...

Upward electrical discharges observed above Tropical Depression Dorian

PubMed Central

Liu, Ningyu; Spiva, Nicholas; Dwyer, Joseph R.; Rassoul, Hamid K.; Free, Dwayne; Cummer, Steven A.

2015-01-01

Observation of upward electrical discharges from thunderstorms has been sporadically reported in the scientific literature. According to their terminal altitudes, they are classified as starters (20–30 km), jets (40–50 km) and gigantic jets (70–90 km). They not only have a significant impact on the occupied atmospheric volumes but also electrically couple different atmospheric regions. However, as they are rare and unpredictable, our knowledge of them has been built on observations that typically record only one type of such discharges. Here we report a close-distance observation of seven upward discharges including one starter, two jets and four gigantic jets above Tropical Depression Dorian. Our optical and electromagnetic data indicate that all events are of negative polarity, suggesting they are initiated in the same thundercloud charge region. The data also indicate that the lightning-like discharge channel can extend above thunderclouds by about 30 km, but the discharge does not emit low-frequency electromagnetic radiation as normal lightning. PMID:25607345

The Planck's character and temperature of visible radiation of a pulse-periodic discharge in cesium vapor

NASA Astrophysics Data System (ADS)

Baksht, F. G.; Lapshin, V. F.

2016-02-01

The radiation spectrum of pulse-periodic discharge in cesium vapor has been simulated in the framework of a two-temperature multifluid radiative gasdynamic model. It is established that, at a broad range of vapor pressures, the discharge spectrum exhibits a Planck character in a significant part of the visible spectral interval, which accounts for the high quality of color rendering in the discharge radiation. The relation between color temperature T c and electron temperature T 0 on the discharge axis is determined by radial optical thickness τ R of the plasma column: T c ≈ T 0 at τ R ≈ 1, T c < T 0 at τ R < 1, and T c > T 0 at τ R > 1. As the vapor pressure increases from 83 to 1087 Torr, color rendering index Ra of the discharge radiation changes from 95 to 98 and the color temperature grows from 3600 to 5200 K.

Spectroscopic investigation of a dielectric barrier discharge in modified atmosphere packaging

NASA Astrophysics Data System (ADS)

Milosavljević, Vladimir; Cullen, Patrick J.

2017-11-01

Diagnostics of a dielectric barrier discharge (DBD), in a sealed package (with and without meat) filled with gas mixtures of oxygen and carbon-dioxide (O2-CO2), is reported. The generation and evaluation of the plasma chemistry induced within the confines of the sealed package is studied. The plasma discharges were analyzed by optical emission spectroscopy (OES) and optical absorption spectroscopy (OAS) over a range of plasma process parameters. The study includes a detailed experimental investigation of the spatial and temporal spectroscopic data and links them with plasma kinetics. The results from the spectral radiation from package provide information about the electron energy distribution function. The experimental data indicates that the humidity level in the package with and without meat is unchanged, and that the gas temperature was not significantly modified. Oxygen and nitrogen radicals (trapped gas atmosphere and modified atmosphere) are increased in the package containing meat; at the same time there is no evidence of the presence of carbon monoxide molecules. The role of the nitrogen molecule in the quenching of O2 and CO2 molecules is also evaluated.

Exploration of the Infrared Sensitivity for a ZnSe Electrode of an IR Image Converter

NASA Astrophysics Data System (ADS)

Kurt, H. Hilal

2018-05-01

Significant improvement has been carried out in the field of the II-VI group semiconductor device technology. Semiconductors based on the II-VI group are attractive due to their alternative uses for thermal imaging systems and photonic applications. This study focuses on experimental work on the optical, electrical and structural characterization of an infrared (IR) photodetector zinc selenide (ZnSe). In addition, the IR sensitivity of the ZnSe has primarily been investigated by exploiting the IR responses of the material for various gas pressures, p, and interelectrode distances, d, in the IR converter. The experimental findings include the results of plasma current and plasma discharge emission under various illumination conditions in the IR region. The electron density distributions inside the gas discharge gap have also been simulated in two-dimensional media. Experimentally, the current-voltage, current-time, and discharge light emission plots are produced for a wide experimental parameter range. Consequently, the structural and optical properties have been studied through atomic force microscopy and Fourier-transform infrared spectroscopy techniques to obtain a comprehensive knowledge of the material.

Conceptual Design of the Nuclear Electronic Xenon Ion System (NEXIS)

NASA Technical Reports Server (NTRS)

Monheiser, Jeff; Polk, Jay; Randolph, Tom

2004-01-01

In support of the NEXIS program, Aerojet-Redmond Operations, with review and input from the JPL and Boeing, has completed the design for a development model (DM) discharge chamber assembly and main discharge cathode assembly. These efforts along with the work by JPL to develop the carbon-carbon-composite ion optics assembly have resulted in a complete ion engine design. The goal of the NEXIS program is to significantly advance the current state of the art by developing an ion engine capable of operating at an input power of 20kW, an Isp of 7500 sec and have a total xenon through put capability of 2000 kg. In this paper we will describe the methodology used to design the discharge chamber and cathode assemblies and describe the resulting final design. Specifics will include the concepts used for the mounting of the ion optics along with the concepts used for the gimbal mounts. In addition, we will present results of a vibrational analysis showing how the engine will respond to a typical Delta IV heavy vibration spectrum.

Discharge Characteristics of DC Arc Water Plasma for Environmental Applications

NASA Astrophysics Data System (ADS)

Li, Tianming; Sooseok, Choi; Takayuki, Watanabe

2012-12-01

A water plasma was generated by DC arc discharge with a hafnium embedded rod-type cathode and a nozzle-type anode. The discharge characteristics were examined by changing the operation parameter of the arc current. The dynamic behavior of the arc discharge led to significant fluctuations in the arc voltage and its frequency. Analyses of the high speed image and the arc voltage waveform showed that the arc discharge was in the restrike mode and its frequency varied within several tens of kilohertz according to the operating conditions. The larger thermal plasma volume was generated by the higher flow from the forming steam with a higher restrike frequency in the higher arc current conditions. In addition, the characteristics of the water plasma jet were investigated by means of optical emission spectroscopy to identify the abundant radicals required in an efficient waste treatment process.

Optical fiber extrinsic Fabry-Perot interferometer sensors for ultrasound detection

NASA Astrophysics Data System (ADS)

Sun, Qingguo; Chen, Na; Ding, Yuetong; Chen, Zhenyi; Wang, Tingyun

2009-11-01

In this paper, a new method is proposed to fabricate an optical fiber extrinsic Fabry-Perot interferometer (EFPI) as an ultrasonic sensor. An acoustic emission detecting system is constructed based on multiple EFPI sensors and demodulation circuit. Ultrasound detection experiments were done from both traditional piezoelectric transducer (PZT) and high voltage discharge. In the experiments, strong ultrasound signals were detected in both cases. The signal attenuation related to the distance and the angle between the acoustic emission source and the FP sensor are obtained. The results indicate that the receiving angle of the FP sensor is nearly 90° and the maximum detection distance in the air is more than 200cm. Furthermore, four sensors are used to locate the position of the ultrasound source produced by high voltage discharge.

[Morphology determination of multi-needle-to-plate positive corona discharge].

PubMed

Su, Peng-hao; Zhu, Yi-min; Chen, Hai-feng

2008-09-01

Using the method of OES (optical emission spectrum) for measuring N2 emission spectrum, the distribution of the energetic electrons in multi-needle-to-plate positive corona discharge at atmospheric pressure was investigated, and compared with that in negative corona discharge. According to the distribution of N2 second positive band's intensity I(SPB), the outline of the ionization region in glow discharge and the streamer channel were drawn rather accurately. The relationship between I(SPB) and the discharge current I in glow discharge can be obtained through the volume integral of the I(SPB). In glow discharge, both the ionization region scale and I(SPB) are smaller than in negative corona discharge, the electron avalanche develops farther along the radius direction of needle than along axis direction, and only the arrange along axis direction is enhanced slightly with the rise of the applied voltage U. The integral of I(SPB) is second order linear to I. In streamer discharge, the discharge channels develop from needlepoint to the plate, while the shape of the region in which I(SPB) is higher looks like a bullet. The density of energetic electron in the channel farther away from the needlepoint is relatively uniform along the axis direction, but first increases then decreases along the radius direction.

Inactivation of bacteria by a mixed argon and oxygen micro-plasma as a function of exposure time.

PubMed

Weng, Chih-Chiang; Wu, Yi-Te; Liao, Juinn-Der; Kao, Chi-Yuan; Chao, Chih-Cheng; Chang, Juu-En; Hsu, Bo-Wen

2009-04-01

A radio-frequency dielectric barrier discharge (DBD) was applied as a micro-plasma device for the inactivation of bacteria, e.g., Escherichia coli. The cultured bacteria were placed on a polydimethyl siloxane (PDMS) film and placed inside the DBD cavity. The bacteria were exposed to micro-plasmas of varying oxygen/argon ratios for different exposure times. The survival of the bacteria was measured by determining bacterial growth using optical methods. The excited oxygen species increased with the increase in the oxygen to argon ratio as measured by optical emission spectroscopy (OES), but the increase of excited oxygen species in argon micro-plasma did not enhance the inactivation of bacteria. In contrast, increases in the time the bacteria were exposed to the micro-plasma were of importance. The results show that a continuous plasma flow containing energetic and reactive species may result in electro-physical interactions with bacteria exposed to the plasma leading to their inactivation. For currently-employed DBD device, addition of 0.5% oxygen to the argon micro-plasma for an exposure time of 30 sec was optimum for the inactivation of E. coli.

Ischemic Optic Neuropathy in Cardiac Surgery: Incidence and Risk Factors in the United States from the National Inpatient Sample 1998 to 2013.

PubMed

Rubin, Daniel S; Matsumoto, Monica M; Moss, Heather E; Joslin, Charlotte E; Tung, Avery; Roth, Steven

2017-05-01

Ischemic optic neuropathy is the most common form of perioperative visual loss, with highest incidence in cardiac and spinal fusion surgery. To date, potential risk factors have been identified in cardiac surgery by only small, single-institution studies. To determine the preoperative risk factors for ischemic optic neuropathy, the authors used the National Inpatient Sample, a database of inpatient discharges for nonfederal hospitals in the United States. Adults aged 18 yr or older admitted for coronary artery bypass grafting, heart valve repair or replacement surgery, or left ventricular assist device insertion in National Inpatient Sample from 1998 to 2013 were included. Risk of ischemic optic neuropathy was evaluated by multivariable logistic regression. A total of 5,559,395 discharges met inclusion criteria with 794 (0.014%) cases of ischemic optic neuropathy. The average yearly incidence was 1.43 of 10,000 cardiac procedures, with no change during the study period (P = 0.57). Conditions increasing risk were carotid artery stenosis (odds ratio, 2.70), stroke (odds ratio, 3.43), diabetic retinopathy (odds ratio, 3.83), hypertensive retinopathy (odds ratio, 30.09), macular degeneration (odds ratio, 4.50), glaucoma (odds ratio, 2.68), and cataract (odds ratio, 5.62). Female sex (odds ratio, 0.59) and uncomplicated diabetes mellitus type 2 (odds ratio, 0.51) decreased risk. The incidence of ischemic optic neuropathy in cardiac surgery did not change during the study period. Development of ischemic optic neuropathy after cardiac surgery is associated with carotid artery stenosis, stroke, and degenerative eye conditions.

Electron density measurements for plasma adaptive optics

NASA Astrophysics Data System (ADS)

Neiswander, Brian W.

Over the past 40 years, there has been growing interest in both laser communications and directed energy weapons that operate from moving aircraft. As a laser beam propagates from an aircraft in flight, it passes through boundary layers, turbulence, and shear layers in the near-region of the aircraft. These fluid instabilities cause strong density gradients which adversely affect the transmission of laser energy to a target. Adaptive optics provides corrective measures for this problem but current technology cannot respond quickly enough to be useful for high speed flight conditions. This research investigated the use of plasma as a medium for adaptive optics for aero-optics applications. When a laser beam passes through plasma, its phase is shifted proportionally to the electron density and gas heating within the plasma. As a result, plasma can be utilized as a dynamically controllable optical medium. Experiments were carried out using a cylindrical dielectric barrier discharge plasma chamber which generated a sub-atmospheric pressure, low-temperature plasma. An electrostatic model of this design was developed and revealed an important design constraint relating to the geometry of the chamber. Optical diagnostic techniques were used to characterize the plasma discharge. Single-wavelength interferometric experiments were performed and demonstrated up to 1.5 microns of optical path difference (OPD) in a 633 nm laser beam. Dual-wavelength interferometry was used to obtain time-resolved profiles of the plasma electron density and gas heating inside the plasma chamber. Furthermore, a new multi-wavelength infrared diagnostic technique was developed and proof-of-concept simulations were conducted to demonstrate the system's capabilities.

Treatment Characteristics of Polysaccharides and Endotoxin Using Oxygen Plasma Produced by RF Discharge

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

Kitazaki, Satoshi; Hayashi, Nobuya; Goto, Masaaki

Treatment of polysaccharides and endotoxin were attempted using oxygen plasma produced by RF discharge. Oxygen radicals observed by optical light emission spectra are factors of decomposition of polysaccharides and endotoxin. Fourier transform infrared spectra indicate that most of chemical bonds in the polysaccharides are dissociated after irradiation of the oxygen plasma. Also, the decomposition rate of endotoxin was approximately 90% after irradiation of the oxygen plasma for 180 min.

Treatment Characteristics of Polysaccharides and Endotoxin Using Oxygen Plasma Produced by RF Discharge

NASA Astrophysics Data System (ADS)

Kitazaki, Satoshi; Hayashi, Nobuya; Goto, Masaaki

2010-10-01

Treatment of polysaccharides and endotoxin were attempted using oxygen plasma produced by RF discharge. Oxygen radicals observed by optical light emission spectra are factors of decomposition of polysaccharides and endotoxin. Fourier transform infrared spectra indicate that most of chemical bonds in the polysaccharides are dissociated after irradiation of the oxygen plasma. Also, the decomposition rate of endotoxin was approximately 90% after irradiation of the oxygen plasma for 180 min.

Laser-Based Optical System for Reactive Radical Concentration Measurements in Plasmas and Flames

DTIC Science & Technology

2006-08-01

role of different plasma components in chain propagation support: (1) and (2) - corona plasma generators with high-voltage multiple needle electrodes ; (3...H20 2) and HCN. Measurements in Gliding Arc, Dielectric Barrier Discharge and Pulsed Corona Plasma systems and in flame and flow reactor systems are...discharges operating in air with iron electrodes - 260V.35 Using visual quantification from high speed camera arc images, the approximate thickness of

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.

Suspended-sediment loads in the lower Stillaguamish River, Snohomish County, Washington, 2014–15

USGS Publications Warehouse

Anderson, Scott A.; Curran, Christopher A.; Grossman, Eric E.

2017-08-03

Continuous records of discharge and turbidity at a U.S. Geological Survey (USGS) streamgage in the lower Stillaguamish River were paired with discrete measurements of suspended-sediment concentration (SSC) in order to estimate suspended-sediment loads over the water years 2014 and 2015. First, relations between turbidity and SSC were developed and used to translate the continuous turbidity record into a continuous estimate of SSC. Those concentrations were then used to predict suspended-sediment loads based on the current discharge record, reported at daily intervals. Alternative methods were used to in-fill a small number of days with either missing periods of turbidity or discharge records. Uncertainties in our predictions at daily and annual time scales were estimated based on the parameter uncertainties in our turbidity-SSC regressions. Daily loads ranged from as high as 121,000 tons during a large autumn storm to as low as –56 tons, when tidal return flow moved more sediment upstream than river discharge did downstream. Annual suspended-sediment loads for both water years were close to 1.4 ± 0.2 million tons.

Comparison of costs and discharge outcomes for patients hospitalized for ischemic or hemorrhagic stroke with or without atrial fibrillation in the United States.

PubMed

Pan, Xianying; Simon, Teresa A; Hamilton, Melissa; Kuznik, Andreas

2015-05-01

This retrospective analysis investigated the impact of baseline clinical characteristics, including atrial fibrillation (AF), on hospital discharge status (to home or continuing care), mortality, length of hospital stay, and treatment costs in patients hospitalized for stroke. The analysis included adult patients hospitalized with a primary diagnosis of ischemic or hemorrhagic stroke between January 2006 and June 2011 from the premier alliance database, a large nationally representative database of inpatient health records. Patients included in the analysis were categorized as with or without AF, based on the presence or absence of a secondary listed diagnosis of AF. Irrespective of stroke type (ischemic or hemorrhagic), AF was associated with an increased risk of mortality during the index hospitalization event, as well as a higher probability of discharge to a continuing care facility, longer duration of stay, and higher treatment costs. In patients hospitalized for a stroke event, AF appears to be an independent risk factor of in-hospital mortality, discharge to continuing care, length of hospital stay, and increased treatment costs.

Chopper-controlled discharge life cycling studies on lead-acid batteries

NASA Technical Reports Server (NTRS)

Kraml, J. J.; Ames, E. P.

1982-01-01

State-of-the-art 6 volt lead-acid golf car batteries were tested. A daily charge/discharge cycling to failure points under various chopper controlled pulsed dc and continuous current load conditions was undertaken. The cycle life and failure modes were investigated for depth of discharge, average current chopper frequency, and chopper duty cycle. It is shown that battery life is primarily and inversely related to depth of discharge and discharge current. Failure mode is characterized by a gradual capacity loss with consistent evidence of cell element aging.

Can We Improve the Tolerance of an Ocular Prosthesis by Enhancing Its Surface Finish?

PubMed

Litwin, Andre S; Worrell, Emma; Roos, Jonathan C P; Edwards, Barry; Malhotra, Raman

Patients who wear an ocular prosthesis frequently suffer with dry eye symptoms and socket discharge, often on a daily basis. The aim of the study was to determine whether a smoother, optical quality polish of the prosthesis' surface could improve symptoms and wear tolerance. The study was designed as single-center, single-masked, prospective randomized controlled trial. Eighty-eight consecutive patients undergoing annual ocular prosthesis maintenance review were approached from the prosthesis clinic. Forty-one out of 49 eligible patients were recruited. Participants were randomized to either a standard or a higher "optical quality" polish of their prosthesis. At entry to the trial, at 1 month, and 12 months they completed a questionnaire covering cleaning, lubricant use, inflammation, discomfort, and discharge. Lower scores indicated better tolerance of the prosthesis. At each visit, the prosthesis was stained and photographed against a standard background to assess deposit build up. Primary outcome measures were 1) a subjective questionnaire score and 2) an objective assessment of surface deposit build-up on prosthetic eyes by standardized photographic grading. Forty-one patients participated in the study. The median age of their prosthesis was 36 months (range 9 months-40 years). There was no statistically significant difference in questionnaire scores or deposit build up between the 2 groups at baseline. By 12-months, the higher optical quality polish showed a statistically significant reduction in symptoms and frequency of discharge (2.19 vs. 3.85; p = 0.05-lower scores better). Scoring of the prosthesis' deposit build-up showed a significant difference at 1 month, but this was not sustained at 12 months. Creating an optical quality finish to an ocular prosthesis reduces deposit build up on artificial eyes. The authors found this modification improved patient tolerance at 12 months.

Secondary preventive medication persistence and adherence 1 year after stroke.

PubMed

Bushnell, C D; Olson, D M; Zhao, X; Pan, W; Zimmer, L O; Goldstein, L B; Alberts, M J; Fagan, S C; Fonarow, G C; Johnston, S C; Kidwell, C; Labresh, K A; Ovbiagele, B; Schwamm, L; Peterson, E D

2011-09-20

Data on long-term use of secondary prevention medications following stroke are limited. The Adherence eValuation After Ischemic stroke-Longitudinal (AVAIL) Registry assessed patient, provider, and system-level factors influencing continuation of prevention medications for 1 year following stroke hospitalization discharge. Patients with ischemic stroke or TIA discharged from 106 hospitals participating in the American Heart Association Get With The Guidelines-Stroke program were surveyed to determine their use of warfarin, antiplatelet, antihypertensive, lipid-lowering, and diabetes medications from discharge to 12 months. Reasons for stopping medications were ascertained. Persistence was defined as continuation of all secondary preventive medications prescribed at hospital discharge, and adherence as continuation of prescribed medications except those stopped according to health care provider instructions. Of the 2,880 patients enrolled in AVAIL, 88.4% (2,457 patients) completed 1-year interviews. Of these, 65.9% were regimen persistent and 86.6% were regimen adherent. Independent predictors of 1-year medication persistence included fewer medications prescribed at discharge, having an adequate income, having an appointment with a primary care provider, and greater understanding of why medications were prescribed and their side effects. Independent predictors of adherence were similar to those for persistence. Although up to one-third of stroke patients discontinued one or more secondary prevention medications within 1 year of hospital discharge, self-discontinuation of these medications is uncommon. Several potentially modifiable patient, provider, and system-level factors associated with persistence and adherence may be targets for future interventions.

The Meteorology of Storms that Produce Narrow Bipolar Events

NASA Technical Reports Server (NTRS)

Lang, Timothy; McCaul, Bill; Fuchs, Brody; Cummer, Steve

2013-01-01

Narrow Bipolar Event's (NBE) are compact (< 2 km), powerful (> 10 kW in VHF), and impulsive (approx 10 micro s) electrical discharges in thunderstorms, also known as compact intracloud discharges (CIDs). Can be either positive or negative polarity and have distinctive broadband waveform signatures sometimes confused for +CGs in the past by NLDN and other networks. NBEs are related to lightning but are likely optically "dark". As revealed by VHF sensors (both satellite and ground): (1) The most powerful lightning-­-related VHF sources observed (2) Tend to occur at the beginning of intracloud discharges (3) Difficult to estimate altitude properly due to receiver saturation.

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.

42 CFR § 512.600 - Waiver of direct supervision requirement for certain post-discharge home visits.

Code of Federal Regulations, 2010 CFR

2017-10-01

... & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) HEALTH CARE INFRASTRUCTURE AND MODEL PROGRAMS EPISODE PAYMENT MODEL Waivers § 512.600 Waiver of direct supervision requirement for certain post...-discharge home visits. (c) Payment. Up to the maximum post-discharge home visits for a specific EPM episode...

46 CFR 153.351 - Location of 4m vent discharges.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 5 2014-10-01 2014-10-01 false Location of 4m vent discharges. 153.351 Section 153.351 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS... Venting Systems § 153.351 Location of 4m vent discharges. Except as prescribed in § 153.353, a 4m venting...

46 CFR 153.350 - Location of B/3 vent discharges.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 5 2014-10-01 2014-10-01 false Location of B/3 vent discharges. 153.350 Section 153.350 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS... Venting Systems § 153.350 Location of B/3 vent discharges. Except as prescribed in § 153.353, a B/3...

Laser-guided, intersecting discharge channels for the final beam transport in heavy-ion fusion

NASA Astrophysics Data System (ADS)

Niemann, C.; Neff, S.; Tauschwitz, A.; Penache, D.; Birkner, R.; Constantin, C.; Knobloch, R.; Presura, R.; Rosmej, F. B.; Hoffmann, D. H. H.; Yu, S. S.

2003-06-01

Ion-beam transport in space charge neutralizing discharge channels has been proposed for the final focus and chamber transport in a heavy-ion fusion reactor. A driver scenario with two-sided target illumination requires a system of two intersecting discharges to transport beams of the same charge from opposite sides towards the fusion target. In this article we report on experiments on the creation of free-standing, intersecting high-current discharge channels. The discharges are initiated in ammonia gas (NH3) in a metallic chamber by two perpendicular CO2-laser beams, which resonantly heat and subsequently rarefy the gas along the laser paths before the breakdown. These low density channels guide the discharges along the predefined paths and also around the 90° angles without any mechanical guiding structures. In this way stable X-, T-, and L-shaped discharges with currents in excess of 40 kA, at pressures of a few mbar were created with a total length of 110 cm. An 11.4 A MeV 58Ni+12 beam from the UNILAC (Universal Linear Accelerator) linear accelerator was used to probe the line-integrated ion-optical properties of the central channel in a T-shaped discharge.

Effect of energetic electrons on combustion of premixed burner flame

NASA Astrophysics Data System (ADS)

Sasaki, Koichi

2011-10-01

In many studies of plasma-assisted combustion, authors superpose discharges onto flames to control combustion reactions. This work is motivated by more fundamental point of view. The standpoint of this work is that flames themselves are already plasmas. We irradiated microwave power onto premixed burner flame with the intention of heating electrons in it. The microwave power was limited below the threshold for a discharge. We obtained the enhancement of burning velocity by the irradiation of the microwave power, which was understood by the shortening of the flame length. At the same time, we observed the increases in the optical emission intensities of OH and CH radicals. Despite the increases in the optical emission intensities, the optical emission spectra of OH and CH were not affected by the microwave irradiation, indicating that the enhancement of the burning velocity was not attributed to the increase in the gas temperature. On the other hand, we observed significant increase in the optical emission intensity of the second positive system of molecular nitrogen, which is a clear evidence for electron heating in the premixed burner flame. Therefore, it is considered that the enhancement of the burning velocity is obtained by nonequilibrium combustion chemistry which is driven by energetic electrons. By irradiating pulsed microwave power, we examined the time constants for the increases and decreases in the optical emission intensities of N2, OH, CH, and continuum radiation.

Very low frequency radio signatures of transient luminous events above thunderstorms

NASA Astrophysics Data System (ADS)

Marshall, Robert Andrew

Lightning discharges emit intense optical and acoustic energy, in the form of lightning and thunder, respectively, but a large amount of energy is emitted as radio-frequency electromagnetic pulses (EMP). These pulses can be detected thousands of kilometers away, thanks to efficient propagation in the waveguide formed by the conducting Earth and the overlying ionosphere. In addition, intense discharges interact with the overlying ionosphere at 80-100 km altitude. The EMP-ionosphere interaction is directly observed in one manifestation as the bright transient optical emissions known as "elves", but in addition, the interaction can directly modify the free electron density in the nighttime lower ionosphere. Modifications of the ionospheric electron density can be detected via subionospheric Very Low Frequency (VLF) remote sensing. In this method, coherent signals from powerful VLF transmitters, built for submarine communication and operated by the Navy, are monitored and their amplitude and phase are tracked in time. The variations of these signais are used to sense ionospheric modifications through rapid changes in the received amplitude and/or phase when the transmitted signal propagates through an ionospheric perturbation. When these perturbations are caused by lightning, they are known as "Early VLF" perturbations, due to the negligible delay between the lightning discharge and the appearance of the VLF signal change, whereas lightning-induced electron precipitation (LEP) events have a delay of 1--2 seconds. In this work, correlations between VLF signatures and optical events are used to show that these Early VLF events may be the signature of ionospheric modification by in-cloud (IC) lightning discharges. While the more impressive cloud-to-ground (CG) lightning discharges are more commonly observed and better understood, they are outnumbered in occurrence 3:1 by IC discharges, whose effects may be relatively stronger in the overlying ionosphere. We use a 3D time-domain model of the lightning EMP-ionosphere interaction to calculate expected ionospheric density changes from IC discharges. We find that bursts of IC-EMPs can significantly modify the lower ionosphere, with both increases and decreases in electron density. We then use a frequency-domain model of the VLF transmitter signal propagation in the Earth-ionosphere waveguide to a receiver to show that these density changes are consistent with measurements. Our results demonstrate that these Early VLF events, which are ubiquitous in VLF data, are signatures of the effects of in-cloud lightning, and that they can be used to quantify the effects of IC lightning on the ionosphere during an intense thunderstorm.

48 CFR 252.225-7039 - Contractors performing private security functions.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., Tagging, Labeling, and Marking of Government-Furnished Property, and physically marked in accordance with... countermeasures (other than the discharge of a weapon, including laser optical distracters, acoustic hailing...

48 CFR 252.225-7039 - Contractors performing private security functions.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., Tagging, Labeling, and Marking of Government-Furnished Property, and physically marked in accordance with... countermeasures (other than the discharge of a weapon, including laser optical distracters, acoustic hailing...

Spatially continuous distributed fiber optic sensing using optical carrier based microwave interferometry.

PubMed

Huang, Jie; Lan, Xinwei; Luo, Ming; Xiao, Hai

2014-07-28

This paper reports a spatially continuous distributed fiber optic sensing technique using optical carrier based microwave interferometry (OCMI), in which many optical interferometers with the same or different optical path differences are interrogated in the microwave domain and their locations can be unambiguously determined. The concept is demonstrated using cascaded weak optical reflectors along a single optical fiber, where any two arbitrary reflectors are paired to define a low-finesse Fabry-Perot interferometer. While spatially continuous (i.e., no dark zone), fully distributed strain measurement was used as an example to demonstrate the capability, the proposed concept may also be implemented on other types of waveguide or free-space interferometers and used for distributed measurement of various physical, chemical and biological quantities.

33 CFR 155.430 - Standard discharge connections for oceangoing ships of 400 gross tons and above.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION OIL OR HAZARDOUS MATERIAL POLLUTION PREVENTION REGULATIONS FOR VESSELS Vessel Equipment § 155.430 Standard discharge connections for...

40 CFR 125.67 - Increase in effluent volume or amount of pollutants discharged.

Code of Federal Regulations, 2014 CFR

2014-07-01

... AGENCY (CONTINUED) WATER PROGRAMS CRITERIA AND STANDARDS FOR THE NATIONAL POLLUTANT DISCHARGE ELIMINATION... projections of effluent volume and mass loadings for any pollutants to which the modification applies in 5...

Attachment process in rocket-triggered lightning strokes

NASA Astrophysics Data System (ADS)

Wang, D.; Rakov, V. A.; Uman, M. A.; Takagi, N.; Watanabe, T.; Crawford, D. E.; Rambo, K. J.; Schnetzer, G. H.; Fisher, R. J.; Kawasaki, Z.-I.

1999-01-01

In order to study the lightning attachment process, we have obtained highly resolved (about 100 ns time resolution and about 3.6 m spatial resolution) optical images, electric field measurements, and channel-base current recordings for two dart leader/return-stroke sequences in two lightning flashes triggered using the rocket-and-wire technique at Camp Blanding, Florida. One of these two sequences exhibited an optically discernible upward-propagating discharge that occurred in response to the approaching downward-moving dart leader and connected to this descending leader. This observation provides the first direct evidence of the occurrence of upward connecting discharges in triggered lightning strokes, these strokes being similar to subsequent strokes in natural lightning. The observed upward connecting discharge had a light intensity one order of magnitude lower than its associated downward dart leader, a length of 7-11 m, and a duration of several hundred nanoseconds. The speed of the upward connecting discharge was estimated to be about 2 × 107 m/s, which is comparable to that of the downward dart leader. In both dart leader/return-stroke sequences studied, the return stroke was inferred to start at the point of junction between the downward dart leader and the upward connecting discharge and to propagate in both upward and downward directions. This latter inference provides indirect evidence of the occurrence of upward connecting discharges in both dart leader/return-stroke sequences even though one of these sequences did not have a discernible optical image of such a discharge. The length of the upward connecting discharges (observed in one case and inferred from the height of the return-stroke starting point in the other case) is greater for the event that is characterized by the larger leader electric field change and the higher return-stroke peak current. For the two dart leader/return-stroke sequences studied, the upward connecting discharge lengths are estimated to be 7-11 m and 4-7 m, with the corresponding return-stroke peak currents being 21 kA and 12 kA, and the corresponding leader electric field changes 30 m from the rocket launcher being 56 kV/m and 43 kV/m. Additionally, we note that the downward dart leader light pulse generally exhibits little variation in its 10-90% risetime and peak value over some tens of meters above the return-stroke starting point, while the following return-stroke light pulse shows an appreciable increase in risetime and a decrease in peak value while traversing the same section of the lightning channel. Our findings regarding (1) the initially bidirectional development of return-stroke process and (2) the relatively strong attenuation of the upward moving return-stroke light (and by inference current) pulse over the first some tens of meters of the channel may have important implications for return-stroke modeling.

Vacuum suppression of acousto-optic self-modulation in a broad-area Nd-doped yttrium-aluminum-garnet single-shot laser

NASA Astrophysics Data System (ADS)

Rus, M. Odín Soler; Cabrera-Granado, E.; Guerra Pérez, J. M.

2013-07-01

We report on the origin of an acousto-optic Raman-Nath self-modulation found in a broad-area Nd:YAG single-shot laser. Operating the laser device under vacuum conditions suppresses the spectral splitting associated with acousto-optic modulation by the shock waves produced by the discharge of the pumping flash lamps. This splitting is reproduced by a general class B laser model that takes into account the dynamical density grating generated by a stationary acoustic radial wave.

Prospects for the Thomson scattering system on NSTX-Upgrade.

PubMed

Diallo, A; LeBlanc, B P; Labik, G; Stevens, D

2012-10-01

The paper discusses the projected configuration of the Thomson system on the National Spherical Torus Experiment (NSTX-U). In this paper, we discuss the projected configuration of the Thomson system on NSTX-U. More specifically, we determine, through both optical modeling of the collection optics and in-vessel measurements, that the collecting fibers are to be displaced by at most 1 cm toward the imaging plane along the optical axis. Finally, we estimate the performance of the Thomson system in measuring the electron temperature for NSTX-U discharges.

Thiol surface functionalization via continuous phase plasma polymerization of allyl mercaptan, with subsequent maleimide-linked conjugation of collagen.

PubMed

Stynes, Gil D; Gengenbach, Thomas R; Kiroff, George K; Morrison, Wayne A; Kirkland, Mark A

2017-07-01

Thiol groups can undergo a large variety of chemical reactions and are used in solution phase to conjugate many bioactive molecules. Previous research on solid substrates with continuous phase glow discharge polymerization of thiol-containing monomers may have been compromised by oxidation. Thiol surface functionalization via glow discharge polymerization has been reported as requiring pulsing. Herein, continuous phase glow discharge polymerization of allyl mercaptan (2-propene-1-thiol) was used to generate significant densities of thiol groups on a mixed macrodiol polyurethane and tantalum. Three general classes of chemistry are used to conjugate proteins to thiol groups, with maleimide linkers being used most commonly. Here the pH specificity of maleimide reactions was used effectively to conjugate surface-bound thiol groups to amine groups in collagen. XPS demonstrated surface-bound thiol groups without evidence of oxidation, along with the subsequent presence of maleimide and collagen. Glow discharge reactor parameters were optimized by testing the resistance of bound collagen to degradation by 8 M urea. The nature of the chemical bonding of collagen to surface thiol groups was effectively assessed by colorimetric assay (ELISA) of residual collagen after incubation in 8 M urea over 8 days and after incubation with keratinocytes over 15 days. The facile creation of useable solid-supported thiol groups via continuous phase glow discharge polymerization of allyl mercaptan opens a route for attaching a vast array of bioactive molecules. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1940-1948, 2017. © 2017 Wiley Periodicals, Inc.

Plasma cleaning of beamline optical components: Contamination and gas composition effects

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

Rosenberg, R.A.; Smith, J.A.; Wallace, D.J.

1992-01-01

We have initiated a program to study the impact of gas composition on the carbon removal rate during plasma cleaning of optical components, and of possible contamination due to the plasma processing. The measurements were performed in a test chamber designed to simulate the geometry of the grating/Codling mirror section of a Grasshopper monochromator. Removal rates were determined for a direct-current (dc) (Al electrode) discharge using a quartz crystal microbalance coated with polymethylmethacrylate, located at the position of the grating. Auger electron spectroscopy analysis of strateg- ically located, gold-coated stainless steel samples was employed to determine contamination. The relative removalmore » rates of the gases studied were 3% C{sub 2}F{sub 6}/O{sub 2}{much gt} O{sub 2}+H{sub 2}O{gt}O{sub 2}{similar to}N{sub 2}O{gt}H{sub 2}{gt}N{sub 2}. Although the C{sub 2}F{sub 6}/O{sub 2} gas mixture showed a 20 times greater removal rate than its nearest competitor, it also caused significant contamination to occur. Contamination studies were performed for both dc and radio-frequency (rf) discharges. For the dc discharge we found that great care must be taken in order to avoid Al contamination; for the rf discharge, significant Fe contamination was observed.« less

Hydraulic Geometry Characteristics of Continuous-Record Streamflow-Gaging Stations on Four Urban Watersheds Along the Main Stem of Gwynns Falls, Baltimore County and Baltimore City, Maryland

USGS Publications Warehouse

Doheny, Edward J.; Fisher, Gary T.

2007-01-01

Four continuous-record streamflow-gaging stations are currently being operated by the U.S. Geological Survey on the main stem of Gwynns Falls in western Baltimore County and Baltimore City, Maryland. The four streamflow-gaging stations drain urban or suburban watersheds with significantly different drainage areas. In addition to providing continuous- record discharge data at these four locations, operation of these stations also provides a long-term record of channel geometry variables such as cross-sectional area, channel width, mean channel depth, and mean velocity that are obtained from physical measurement of the discharge at a variety of flow conditions. Hydraulic geometry analyses were performed using discharge-measurement data from four continuous-record streamflow-gaging stations on the main stem of Gwynns Falls. Simple linear regression was used to develop relations that (1) quantify changes in cross-sectional area, channel width, mean channel depth, and mean velocity with changes in discharge at each station, and (2) quantify changes in these variables in the Gwynns Falls watershed with changes in drainage area and annual mean discharge. Results of the hydraulic geometry analyses indicated that mean velocity is more responsive to changes in discharge than channel width and mean channel depth for all four streamflow-gaging stations on the main stem of Gwynns Falls. For the two largest and most developed watersheds, on Gwynns Falls at Villa Nova, and Gwynns Falls at Washington Boulevard at Baltimore, the slope of the regression lines, or hydraulic exponents, indicated that mean velocity was more responsive to changes in discharge than any of the other hydraulic variables that were analyzed. This was true even when considering changes in cross-sectional area with discharge, which incorporates the combined effects of channel width and mean channel depth. A comparison of hydraulic exponents for Gwynns Falls to average values from previous work indicated that the velocity exponents for all four stations on the Gwynns Falls are larger than the average value of 0.34. For stations 01589300 and 01589352, the exponents for mean velocity are about twice as large as the average value. Analyses of cross-sectional area, channel width, mean channel depth, and mean velocity in conjunction with changes in drainage area and annual mean discharge indicated that channel width is much more responsive to changes in drainage area and annual mean discharge than are mean channel depth or mean velocity. Cross-sectional area, which combines the effects of channel width and mean channel depth, was also found to be highly responsive to changes in drainage area and annual mean discharge.

46 CFR 153.470 - System for discharge of NLS residue to the sea: Categories A, B, C, and D.

Code of Federal Regulations, 2012 CFR

2012-10-01

... (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS... discharge of NLS residue to the sea: Categories A, B, C, and D. Unless waived under § 153.491, each ship... cubic meters per hour at which the ship operator wishes to discharge slops (note: Qd affects the...

46 CFR 153.470 - System for discharge of NLS residue to the sea: Categories A, B, C, and D.

Code of Federal Regulations, 2014 CFR

2014-10-01

... (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS... discharge of NLS residue to the sea: Categories A, B, C, and D. Unless waived under § 153.491, each ship... cubic meters per hour at which the ship operator wishes to discharge slops (note: Qd affects the...

46 CFR 153.470 - System for discharge of NLS residue to the sea: Categories A, B, C, and D.

Code of Federal Regulations, 2011 CFR

2011-10-01

... (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS... discharge of NLS residue to the sea: Categories A, B, C, and D. Unless waived under § 153.491, each ship... cubic meters per hour at which the ship operator wishes to discharge slops (note: Qd affects the...

46 CFR 153.470 - System for discharge of NLS residue to the sea: Categories A, B, C, and D.

Code of Federal Regulations, 2010 CFR

2010-10-01

... (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS... discharge of NLS residue to the sea: Categories A, B, C, and D. Unless waived under § 153.491, each ship... cubic meters per hour at which the ship operator wishes to discharge slops (note: Qd affects the...

46 CFR 153.470 - System for discharge of NLS residue to the sea: Categories A, B, C, and D.

Code of Federal Regulations, 2013 CFR

2013-10-01

... (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS... discharge of NLS residue to the sea: Categories A, B, C, and D. Unless waived under § 153.491, each ship... cubic meters per hour at which the ship operator wishes to discharge slops (note: Qd affects the...

32 CFR Appendix C to Part 724 - Samples of Formats Employed by the Naval Discharge Review Board

Code of Federal Regulations, 2011 CFR

2011-07-01

... Discharge Review Board C Appendix C to Part 724 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Pt. 724, App. C Appendix C to Part 724—Samples... to Commandant, Marine Corps (Change). Note: The Forms appearing in appendix C are not carried in the...

32 CFR Appendix C to Part 724 - Samples of Formats Employed by the Naval Discharge Review Board

Code of Federal Regulations, 2012 CFR

2012-07-01

... Discharge Review Board C Appendix C to Part 724 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Pt. 724, App. C Appendix C to Part 724—Samples... to Commandant, Marine Corps (Change). Note: The Forms appearing in appendix C are not carried in the...

32 CFR Appendix C to Part 724 - Samples of Formats Employed by the Naval Discharge Review Board

Code of Federal Regulations, 2010 CFR

2010-07-01

... Discharge Review Board C Appendix C to Part 724 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Pt. 724, App. C Appendix C to Part 724—Samples... to Commandant, Marine Corps (Change). Note: The Forms appearing in appendix C are not carried in the...

An optical switch

DOEpatents

Christophorou, L.G.; Hunter, S.R.

1987-04-30

The invention is a gas mixture for a diffuse discharge switch having an electron attaching gas wherein electron attachment is brought about by indirect excitation of molecules to long live states by exposure to laser light. 3 figs.

Lifetime testing UV LEDs for use in the LISA charge management system

NASA Astrophysics Data System (ADS)

Hollington, D.; Baird, J. T.; Sumner, T. J.; Wass, P. J.

2017-10-01

As a future charge management light source, UV light-emitting diodes (UV LEDs) offer far superior performance in a range of metrics compared to the mercury lamps used in the past. As part of a qualification program a number of short wavelength UV LEDs have been subjected to a series of lifetime tests for potential use on the laser interferometer space antenna (LISA) mission. These tests were performed at realistic output levels for both fast and continuous discharging in either a DC or pulsed mode of operation and included a DC fast discharge test spanning 50 days, a temperature dependent pulsed fast discharge test spanning 21 days and a pulsed continuous discharge test spanning 507 days. Two types of UV LED have demonstrated lifetimes equivalent to over 25 years of realistic mission usage with one type providing a baseline for LISA and the other offering a backup solution.

Improving Continuity of Care via the Discharge Summary

PubMed Central

Sakaguchi, Farrant H.; Lenert, Leslie A.

2015-01-01

Discharge summaries (DCS) frequently fail to improve the continuity of care. A chart review of 188 DCS was performed to identify specific components that could be improved through health information technology. Medication reconciliations were analyzed for completeness and for medical reasoning. Documentation of pending results and follow-up details were analyzed. Patient preferences, patient goals, and the handover tone were noted. Patients were discharged on an average of 9.8 medications, only 3% of medication reconciliations were complete and medical reasoning was frequently absent. There were 358 pending results in 188 hospital discharges though only 14% were mentioned in the DCS. Documentation of clear, timely follow-up was present for less than 50% of patients. Patient preferences, patient goals, and lessons learned were rarely included. A handover tone was in only 17% of the DCS. Evaluating the DCS as a clinical handover is novel but information for safe handovers is frequently missing. PMID:26958250

Shortened lengths of stay: ensuring continuity of care for mothers and babies.

PubMed

Welsh, C; Ludwig-Beymer, P

1998-01-01

Hospital discharge on the day after an uncomplicated vaginal delivery may be appropriate if clinical criteria are used for the selection of patients and post-discharge follow-up plans are in place. To ensure safety for these patients, Advocate Health Care developed a mother/baby philosophy statement, guidelines for maternal and infant discharge in less than 48 hours, and an algorithm to assure that appropriate follow-up care takes place after discharge. To evaluate the Mother/Baby Home Transition Program, home health follow up, readmission rates, and sentinel events were tracked. Most home health visits occurred within 48 hours. Infant readmission rates ranged from 1.1-2.6%, whereas maternal readmission rates ranged from 0-0.52%. Three sentinel events in 1996 and three in 1997 required readmissions to an ICU. Data continue to be monitored and shared monthly with clinical leaders.

Diffusion cannot govern the discharge of neurotransmitter in fast synapses.

PubMed Central

Khanin, R; Parnas, H; Segel, L

1994-01-01

In the present work we show that diffusion cannot provide the observed fast discharge of neurotransmitter from a synaptic vesicle during neurotransmitter release, mainly because it is not sufficiently rapid nor is it sufficiently temperature-dependent. Modeling the discharge from the vesicle into the cleft as a continuous point source, we have determined that discharge should occur in 50-75 microseconds, to provide the observed high concentrations of transmitter at the critical zone. Images FIGURE 5 PMID:7811953

Process Inference from High Frequency Temporal Variations in Dissolved Organic Carbon (DOC) Dynamics Across Nested Spatial Scales

NASA Astrophysics Data System (ADS)

Tunaley, C.; Tetzlaff, D.; Lessels, J. S.; Soulsby, C.

2014-12-01

In order to understand aquatic ecosystem functioning it is critical to understand the processes that control the spatial and temporal variations in DOC. DOC concentrations are highly dynamic, however, our understanding at short, high frequency timescales is still limited. Optical sensors which act as a proxy for DOC provide the opportunity to investigate near-continuous DOC variations in order to understand the hydrological and biogeochemical processes that control concentrations at short temporal scales. Here we present inferred 15 minute stream water DOC data for a 12 month period at three nested scales (1km2, 3km2 and 31km2) for the Bruntland Burn, a headwater catchment in NE Scotland. High frequency data were measured using FDOM and CDOM probes which work by measuring the fluorescent component and coloured component, respectively, of DOC when exposed to ultraviolet light. Both FDOM and CDOM were strongly correlated (r2 >0.8) with DOC allowing high frequency estimations. Results show the close coupling of DOC with discharge throughout the sampling period at all three spatial scales. However, analysis at the event scale highlights anticlockwise hysteresis relationships between DOC and discharge due to the delay in DOC being flushed from the increasingly large areas of peaty soils as saturation zones expand and increase hydrological connectivity. Lag times vary between events dependent on antecedent conditions. During a 10 year drought period in late summer 2013 it was apparent that very small changes in discharge on a 15 minute timescale result in high increases in DOC. This suggests transport limitation during this period where DOC builds up in the soil and is not flushed regularly, therefore any subsequent increase in discharge results in large DOC peaks. The high frequency sensors also reveal diurnal variability during summer months related to the photo-oxidation, evaporative and biological influences of DOC during the day. This relationship is less significant during the winter months.

Characterization of microwave discharge plasmas for surface processing

NASA Astrophysics Data System (ADS)

Nikolic, Milka

We have developed several diagnostic techniques to characterize two types of microwave (MW) discharge plasmas: a supersonic flowing argon MW discharge maintained in a cylindrical quartz cavity at frequency ƒ = 2.45 GHz and a pulse repetitive MW discharge in air at ƒ = 9.5 GHz. Low temperature MW discharges have been proven to posses attractive properties for plasma cleaning and etching of niobium surfaces of superconductive radio frequency (SRF) cavities. Plasma based surface modification technologies offer a promising alternative for etching and cleaning of SRF cavities. These technologies are low cost, environmentally friendly and easily controllable, and present a possible alternative to currently used acid based wet technologies, such as buffered chemical polishing (BCP), or electrochemical polishing (EP). In fact, weakly ionized. non-equilibrium, and low temperature gas discharges represent a powerful tool for surface processing due to the strong chemical reactivity of plasma radicals. Therefore, characterizing these discharges by applying non-perturbing, in situ measurement techniques is of vital importance. Optical emission spectroscopy has been employed to analyze the molecular structure and evaluate rotational and vibrational temperatures in these discharges. The internal plasma structure was studied by applying a tomographic numerical method based on the two-dimensional Radon formula. An automated optical measurement system has been developed for reconstruction of local plasma parameters. It was found that excited argon states are concentrated near the tube walls, thus confirming the assumption that the post discharge plasma is dominantly sustained by a travelling surface wave. Employing a laser induced fluorescence technique in combination with the time synchronization device allowed us to obtain time-resolved population densities of some excited atomic levels in argon. We have developed a technique for absolute measurements of electron density based on the time-resolved absolute intensity of a Nitrogen spectral band belonging to the Second Positive System, the kinetic model and the detailed particle balance of the N2 (C 3piu) state. Measured electron density waveforms are in fair agreement with electron densities obtained using the Stark broadening technique. In addition, time dependent population densities of Ar I metastable and resonant levels were obtained by employing a kinetic model developed based on analysis of population density rates of excited Ar I p levels. Both the experimental results and numerical models for both types of gas discharges indicate that multispecies chemistry of gases plays an important role in understanding the dynamics and characterizing the properties of these discharges.

Time-resolved processes in a pulsed electrical discharge in argon bubbles in water

NASA Astrophysics Data System (ADS)

Gershman, S.; Belkind, A.

2010-12-01

A phenomenological picture of a pulsed electrical discharge in gas bubbles in water is produced by combining electrical, spectroscopic, and imaging characterization methods. The discharge is generated by applying 1 μ s pulses of 5 to 20 kV between a needle and a disk electrode submerged in water. An Ar gas bubble surrounds the tip of the needle electrode. Imaging, electrical characteristics, and time-resolved optical emission spectroscopic data suggest a fast streamer propagation mechanism and the formation of a plasma channel in the bubble. Comparing the electrical and imaging data for consecutive pulses applied to the bubble 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 the presence of long-lived chemical species, such as ozone and oxygen. Imaging and electrical data show the presence of two discharge events during each applied voltage pulse, a forward discharge near the beginning of the applied pulse depositing charge on the surface of the bubble and a reverse discharge removing the accumulated charge from the water/gas interface when the applied voltage is turned off. The pd value of ~ 300-500 torr cm, the 1 μs long pulse duration, low repetition rate, and unidirectional character of the applied voltage pulses make the discharge process here unique compared to the traditional corona or dielectric barrier discharges.

Photo-triggering and secondary electron produced ionization in electric discharge ArF* excimer lasers

NASA Astrophysics Data System (ADS)

Xiong, Zhongmin; Kushner, Mark J.

2011-10-01

Electric discharge excimer lasers are sustained in multi-atmosphere attaching gas mixtures that are typically preionized to enable a reproducible, uniform glow, which maximizes optical quality and gain. This preionization is often accomplished using UV light produced by a corona discharge within the plasma cavity. To quantify the relationship between corona discharge properties and those of the laser discharge, the triggering of electron avalanche by preionizing UV light in an electric discharge-pumped ArF* excimer laser was numerically investigated using a two-dimensional model. The preionizing UV fluxes were generated by a corona-bar discharge driven by the same voltage pulse as the main discharge sustained in a multi-atmospheric Ne/Ar/Xe/F2 gas mixture. The resulting peak photo-electron density in the inter-electrode spacing is around 108 cm-3, and its distribution is biased toward the UV source. The preionization density increases with increasing dielectric constant and capacitance of the corona bar. The symmetry and uniformity of the discharge are, however, improved significantly once the main avalanche develops. In addition to bulk electron impact ionization, the ionization generated by sheath accelerated secondary electrons was found to be important in sustaining the discharge current at experimentally observed values. At peak current, the magnitude of the ionization by sheath accelerated electrons is comparable to that from bulk electron impact in the vicinity of the cathode.

Initiation of a lightning search using the lightning and airglow camera onboard the Venus orbiter Akatsuki

NASA Astrophysics Data System (ADS)

Takahashi, Yukihiro; Sato, Mitsuteru; Imai, Masataka; Lorenz, Ralph; Yair, Yoav; Aplin, Karen; Fischer, Georg; Nakamura, Masato; Ishii, Nobuaki; Abe, Takumi; Satoh, Takehiko; Imamura, Takeshi; Hirose, Chikako; Suzuki, Makoto; Hashimoto, George L.; Hirata, Naru; Yamazaki, Atsushi; Sato, Takao M.; Yamada, Manabu; Murakami, Shin-ya; Yamamoto, Yukio; Fukuhara, Tetsuya; Ogohara, Kazunori; Ando, Hiroki; Sugiyama, Ko-ichiro; Kashimura, Hiroki; Ohtsuki, Shoko

2018-05-01

The existence of lightning discharges in the Venus atmosphere has been controversial for more than 30 years, with many positive and negative reports published. The lightning and airglow camera (LAC) onboard the Venus orbiter, Akatsuki, was designed to observe the light curve of possible flashes at a sufficiently high sampling rate to discriminate lightning from other sources and can thereby perform a more definitive search for optical emissions. Akatsuki arrived at Venus during December 2016, 5 years following its launch. The initial operations of LAC through November 2016 have included a progressive increase in the high voltage applied to the avalanche photodiode detector. LAC began lightning survey observations in December 2016. It was confirmed that the operational high voltage was achieved and that the triggering system functions correctly. LAC lightning search observations are planned to continue for several years.

A handheld low temperature atmospheric pressure air plasma gun for nanomaterial synthesis in liquid phase

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

Yu, Shuang; Wang, Kaile; Zuo, Shasha

A handheld low temperature atmospheric pressure air plasma gun based on a dielectric barrier structure with hollow electrodes was proposed. The portable plasma gun with an embedded mini air pump was driven by a 12 V direct voltage battery. The air plasma jet generated from the gun could be touched without a common shock hazard. Besides working in air, the plasma gun can also work in water. The diagnostic result of optical emission spectroscopy showed the difference in reactive species of air plasma jet between in air and in water. The plasma gun was excited in 20 ml chloroauric acid aqueous solutionmore » with a concentration of 1.214 mM. A significant amount of gold nanoparticles were synthesized after 2 min continuous discharge. The plasma gun with these unique features is applicable in plasma medicine, etching, and s-nthesis of nanomaterials.« less

Application of Tracer-Injection Techniques to Demonstrate Surface-Water and Ground-Water Interactions Between an Alpine Stream and the North Star Mine, Upper Animas River Watershed, Southwestern Colorado

USGS Publications Warehouse

Wright, Winfield G.; Moore, Bryan

2003-01-01

Tracer-injection studies were done in Belcher Gulch in the upper Animas River watershed, southwestern Colorado, to determine whether the alpine stream infiltrates into underground mine workings of the North Star Mine and other nearby mines in the area. The tracer-injection studies were designed to determine if and where along Belcher Gulch the stream infiltrates into the mine. Four separate tracer-injec-tion tests were done using lithium bromide (LiBr), optical brightener dye, and sodium chloride (NaCl) as tracer solu-tions. Two of the tracers (LiBr and dye) were injected con-tinuously for 24 hours, one of the NaCl tracers was injected continuously for 12 hours, and one of the NaCl tracers was injected over a period of 1 hour. Concentration increases of tracer constituents were detected in water discharging from the North Star Mine, substantiating a surface-water and ground-water connection between Belcher Gulch and the North Star Mine. Different timing and magnitude of tracer breakthroughs indicated multiple flow paths with different residence times from the stream to the mine. The Pittsburgh and Sultan Mines were thought to physically connect to the North Star Mine, but tracer breakthroughs were inconclusive in water from these mines. From the tracer-injection tests and synoptic measure-ments of streamflow discharge, a conceptual model was devel-oped for surface-water and ground-water interactions between Belcher Gulch and the North Star Mine. This information, combined with previous surface geophysical surveys indicat-ing the presence of subsurface voids, may assist with decision-making process for preventing infiltration and for the remedia-tion of mine drainage from these mines.

3D modeling of lightning-induced electromagnetic pulses on Venus, Jupiter and Saturn

NASA Astrophysics Data System (ADS)

Pérez-Invernón, Francisco J.; Luque, Alejandro; Gordillo-Vázquez, Francisco J.

2017-04-01

Atmospheric electricity is a common phenomenon in some planets of The Solar System. We know that atmospheric discharges exist on Earth and gaseous planets; however, some characteristics of lightning on Saturn and Jupiter as well as their relevance on the effects of lightning in the atmospheres of these planets are still unknown. In the case of Venus, there exist some radio evidences of lightning, but the lack of optical observations suggests exploring indirect methods of detection, such as searching for lightning-induced transient optical emissions from the upper atmosphere. The Akatsuki probe, currently orbiting Venus, is equipped with a camera whose temporal resolution is high enough to detect optical emissions from lightning discharges and to measure nightglow enhancements. In this work, we extend previous models [1,2] to investigate the chemical impact and transient optical emissions produced by possible lightning-emitted electromagnetic pulses (EMP) in Venus, Saturn and Jupiter. Using a 3D FDTD ("Finite Differences Time Domain") model we solve the Maxwell equations coupled with the Langevin equation for electrons [3] and with a kinetic scheme, different for each planetary atmosphere. This method is useful to investigate the temporal and spatial impact of lightning-induced electromagnetic fields in the atmosphere of each planet for different lightning characteristics (e.g. energy released, orientation). This 3D FDTD model allows us to include the saturnian and jovian background magnetic field inclination and magnitude at different latitudes, and to determine the effects of different lightning channel inclinations. Results provide useful information to interpret lightning observations on giant gaseous planets and in the search for indirect optical signals from atmospheric discharge on Venus such as fast nightglow transient enhancements related to lightning as seen on Earth. Furthermore, we underline the observation of electrical discharges characteristics as a powerful tool to obtain information about planetary atmospheres, such as density profiles of electrons or other components. Our model may also be useful to extend some studies about the chemical impact of EMP pulses in the terrestrial atmosphere [4]. References [1] Luque, A., D. Dubrovin, F. J. Gordillo-Vázquez, U. Ebert, F. C. Parra-Rojas, Y. Yair, and C. Price (2014), Coupling between atmospheric layers in gaseous giant planets due to lightning-generated electromagnetic pulses, J. Geophys. Res. (Space Phys), 119, 8705, doi: 10.1002/2014JA020457. [2] Pérez-Invernón, F. J., A. Luque, and F. J. Gordillo-Vázquez (2016), Mesospheric optical signatures of possible lightning on Venus, J. Geophys. Res. (Space Phys), 121, 7026, doi: 10.1029/2016JA022886. [3] Lee, J. H., and D. K. Kalluri (1999), Three-dimensional FDTD simulation of electromagnetic wave transformation in a dynamic inhomogeneous magnetized plasma, IEEE Transactions on Antennas and Propagation, 47, 1146, doi:10.1109/8.785745. [4] Marshall, R. A., U. S. Inan, and V. S. Glukhov (2010), Elves and associated electron density changes due to cloud-to-ground and in-cloud lightning discharges, J. Geophys. Res. (Space Phys), 115, A00E17, doi:10.1029/2009JA014469.

[Information transmission to the community pharmacist after a patient's discharge from the hospital: setting up of a written medication discharge form, prospective evaluation of its impact, and survey of the information needs of the pharmacists].

PubMed

Claeys, C; Dufrasne, M; De Vriese, C; Nève, J; Tulkens, P M; Spinewine, A

2015-03-01

Discharge from the hospital is a period at risk for the continuity of patient's medication (seamless pharmaceutical care). The community pharmacist is often the first health care professional seen by the patient after hospital discharge. The clinical pharmacist has potentially a key role in establishing an efficient information transfer from the hospital to the community pharmacy. (1) To develop and, (2) to evaluate the impact of a structured discharge medication form prepared at hospital discharge by the clinical pharmacist and containing information items related to the medication regimen for the community pharmacist, and (3) to survey the information needs of the Belgian community pharmacists to ensure continuity of care after hospitalization. (1) A structured discharge medication form has been developed based on a Literature review and on opinions expressed by community and clinical pharmacists, members of the Belgian Pharmaceutical Union (Association Pharmaceutique Belge) and an ethical committee. (2) A prospective study has been conducted with patients from geriatrics and orthopaedics wards of the University Hospital Dinant-Godinne returning home after hospital discharge with the discharge medication form to be given to their commuiity pharmacist; its use, the reasons for non-use, the perceived impact and the satisfaction of the community pharmacist have been assessed. (3) An on-line survey addressed to all Belgian community pharmacists evaluated their information needs. (1) The final version of the discharge medication form included key information items concerning the hospital, the patient, the discharge treatment (including the type of modifications made as compared to medications taken before admission), and on medication management at home. Some items were excluded because of Lack of perceived utility by pharmacists, confidentiality issues, and respect of patient's freedom of choice. (2) From the 71 medication forms given to patients, 48 were received by the community pharmacist. One quarter of respondents stated that they did not use the form, the main reason being that it was received after dispensing of the discharge treatment (n=6/11). The majority of the community pharmacists considered most of the information items as useful and the discharge medication form as being valuable for continuity of care. Requests for additional information were made (e.g., reason of admission and of treatment modifications, etc.). (3) The utility, benefits, and need for additional information items beyond what was included in the discharge medication form were highlighted by the respondents (n=309) of the national survey. Most of these respondents confirmed the value of the different information items included in the discharge medication form. The transmission of a structured medication form containing information about the medication regimen upon hospital discharge is of real interest and value for the community pharmacist because it goes beyond what is usually provided on a medical prescription. However, this discharge medication form should include more information items for effective pharmaceutical care.

Spectroscopic investigation of plasma electrolytic borocarburizing on q235 low-carbon steel

NASA Astrophysics Data System (ADS)

Liu, Run; Wang, Bin; Wu, Jie; Xue, Wenbin; Jin, Xiaoyue; Du, Jiancheng; Hua, Ming

2014-12-01

A plasma electrolytic borocarburizing process (PEB/C) in borax electrolyte with glycerin additive was employed to fabricate a hardening layer on Q235 low-carbon steel. Optical emission spectroscopy (OES) was utilized to investigate the spectroscopy characteristics of plasma discharge around the steel during PEB/C process. Some plasma parameters were calculated in terms of OES. The electron temperature and electron concentration in plasma discharge zone is about 3000-12,000 K and 2 × 1022 m-3-1.4 × 1023 m-3. The atomic ionization degrees of iron, carbon and boron are 10-16-10-3, and 10-23-10-6, 10-19-10-4, respectively, which depend on discharge time. The surface morphology and cross-sectional microstructure of PEB/C hardening layer were observed, and the electrolyte decomposition and plasma discharge behaviors were discussed.

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

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

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

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 filamentmore » with increasing distance from the tip of the anode.« less

Understanding DOC Mobilization Dynamics Through High Frequency Measurements in a Headwater Catchment

NASA Astrophysics Data System (ADS)

Werner, B.; Musolff, A.; Lechtenfeld, O.; de Rooij, G. H.; Fleckenstein, J. H.

2017-12-01

Increasing dissolved organic carbon (DOC) exports from headwater catchments impact the quality of downstream waters and pose challenges to water supply. The importance of riparian zones for DOC export from catchments in humid, temperate climates has generally been acknowledged, but the hydrological controls and biogeochemical factors that govern mobilization of DOC from riparian zones remain elusive. By analyzing high-frequency time series of UV-VIS based water quality we therefore aim at a better understanding on temporal dynamics of DOC mobilization and exports. In a first step a one year high frequency (15 minutes) data set from a headwater catchment in the Harz Mountains (Germany) was systematically analyzed for event-based patterns in DOC concentrations. Here, a simplistic linear model was generated to explain DOC concentration level and variability in the stream. Furthermore, spectral (e.g. slopes and SUVA254) and molecular (FT-ICR-MS) characterization of DOC was used to fingerprint in-stream DOC during events. Continuous DOC concentrations were best predicted (R², NSE = 0.53) by instantaneous discharge (Q) and antecede wetness conditions of the last 30 days (AWC30 = Precip.30/PET30) as well as mean air temperature (Tmean30) and mean discharge (Qmean30) of the preceding 30 days. Analyses of 36 events revealed seasonal trends for the slope, intercept and R² of linear log(DOC)-log(Q) regressions that can be best explained by the mean air temperature of the preceding 15 days. Continuously available optical DOC quality parameters SUVA254 and spectral slope (275 nm - 295 nm) systematically changed with shifts in discharge and in DOC concentration. This is underlined by selected FT-ICR-MS measurements indicating higher DOC aromaticity and oxygen content at high flow conditions. The change of DOC quality parameters during events indicate a shift in the activated source zones: DOC with a different quality was mobilized during high flow conditions when higher groundwater levels connected formerly disconnected DOC source zones to the stream. We conclude that the high concentration variability of DOC can be explained by a few controlling variables only. These variables can be linked to event-based DOC source activation and more seasonal controls of DOC production.

[Study on Hexagonal Super-Lattice Pattern with Light Spot and Dim Spot in Dielectric Barrier Discharge by Optical Emission Spectra].

PubMed

Liu, Ying; Dong, Li-fang; Niu, Xue-jiao; Zhang, Chao

2016-02-01

The hexagonal super-lattice pattern composed of the light spot and the dim spot is firstly observed and investigated in the discharge of gas mixture of air and argon by using the dielectric barrier discharge device with double water electrodes. It is found that the dim spot is located at the center of its surrounding three light spots by observing the discharge image. Obviously, the brightness of the light spot and the dim spot are different, which indicates that the plasma states of the light spot and the dim spot may be different. The optical emission spectrum method is used to further study the several plasma parameters of the light spot and the dim spot in different argon content. The emission spectra of the N₂ second positive band (C³IIu --> B³IIg) are measured, from which the molecule vibration temperatures of the light spot and the dim spot are calculated. Based on the relative intensity ratio of the line at 391.4 nm and the N₂ line at 394.1 nm, the average electron energies of the light spot and the dim spot are investigated. The broadening of spectral line 696.57 nm (2P₂-1S₅) is used to study the electron densities of the light spot and the dim spot. The experiment shows that the molecule vibration temperature, average electron energy and the electron density of the dim spot are higher than those of the light spot in the same argon content. The molecule vibration temperature and electron density of the light spot and dim spot increase with the argon content increasing from 70% to 95%, while average electron energies of the light spot and dim spot decrease gradually. The short-exposure image recorded by a high speed video camera shows that the dim spot results from the surface discharges (SDs). The surface discharge induced by the volume discharge (VD) has the decisive effect on the formation of the dim spot. The experiment above plays an important role in studying the formation mechanism of the hexagonal super-lattice pattern with light spot and dim spot. In addition, the studies exert influences on the application of surface discharge and volume discharge in different fields.

Impact of different environmental conditions on lithium-ion batteries performance through the thermal monitoring with fiber sensors

NASA Astrophysics Data System (ADS)

Nascimento, Micael; Ferreira, Marta S.; Pinto, João. L.

2017-08-01

In this work, an optical fiber sensing network has been developed to assess the impact of different environmental conditions on lithium batteries performance through the real time thermal monitoring. The battery is submitted to constant current charge and different discharge C-rates, under normal and abusive operating conditions. The results show that for the discharge C-rate of 5.77C, the LiB under cold and dry climates had 32.5% and 27.2% lower temperature variations, when compared with temperate climates, respectively. The higher temperature shift detected in the temperate climate was related to the battery better performance regarding discharge capacity and power capabilities.

A Multicenter, Randomized, Triple-Masked, Placebo-Controlled Trial of The Effect of Ambulatory Continuous Femoral Nerve Blocks on Discharge-Readiness Following Total Knee Arthroplasty In Patients on General Orthopaedic Wards

PubMed Central

Ilfeld, Brian M.; Mariano, Edward R.; Girard, Paul J.; Loland, Vanessa J.; Meyer, R. Scott; Donovan, John F.; Pugh, George A.; Le, Linda T.; Sessler, Daniel I.; Shuster, Jonathan J.; Theriaque, Douglas W.; Ball, Scott T.

2010-01-01

A continuous femoral nerve block (cFNB) involves the percutaneous insertion of a catheter adjacent to the femoral nerve, followed by a local anesthetic infusion, improving analgesia following total knee arthroplasty (TKA). Portable infusion pumps allow infusion continuation following hospital discharge, raising the possibility of decreasing hospitalization duration. We therefore used a multicenter, randomized, triple-masked, placebo-controlled study design to test the primary hypothesis that a four-day ambulatory cFNB decreases the time until each of three predefined readiness-for-discharge criteria (adequate analgesia, independence from intravenous opioids, and ambulation ≥ 30 meters) are met following TKA compared with an overnight inpatient-only cFNB. Preoperatively, all patients received a cFNB with perineural ropivacaine 0.2% from surgery until the following morning, at which time they were randomized to either continue perineural ropivacaine (n=39) or switch to normal saline (n=38). Patients were discharged with their cFNB and portable infusion pump as early as postoperative day three. Patients given four days of perineural ropivacaine attained all three criteria in a median (25th–75th percentiles) of 47 (29–69) hours, compared with 62 (45–79) hours for those of the control group (Estimated ratio=0.80, 95% confidence interval: 0.66–1.00; p=0.028). Compared with controls, patients randomized to ropivacaine met the discharge criterion for analgesia in 20 (0–38) vs. 38 (15–64) hours (p=0.009), and intravenous opioid independence in 21 (0–37) vs. 33 (11–50) hours (p=0.061). We conclude that a four-day ambulatory cFNB decreases the time to reach three important discharge criteria by an estimated 20% following TKA compared with an overnight cFNB, primarily by improving analgesia. PMID:20573448

Hg(+) Frequency Standards

NASA Technical Reports Server (NTRS)

Prestage, John D.; Tjoelker, Robert L.; Maleki, Lute

2000-01-01

In this paper we review the development of Hg(+) microwave frequency standards for use in high reliability and continuous operation applications. In recent work we have demonstrated short-term frequency stability of 3 x 10(exp -14)/nu(sub tau) when a cryogenic oscillator of stability 2-3 x 10(exp 15) was used a the local oscillator. The trapped ion frequency standard employs a Hg-202 discharge lamp to optically pump the trapped Hg(+)-199 clock ions and a helium buffer gas to cool the ions to near room temperature. We describe a small Hg(+) ion trap based frequency standard with an extended linear ion trap (LITE) architecture which separates the optical state selection region from the clock resonance region. This separation allows the use of novel trap configurations in the resonance region since no optical pumping is carried out there. A method for measuring the size of an ion cloud inside a linear trap with a 12-rod trap is currently being investigated. At approx. 10(exp -12), the 2nd order Doppler shift for trapped mercury ion frequency standards is one of the largest frequency offsets and its measurement to the 1% level would represent an advance in insuring the very long-term stability of these standards to the 10(exp -14) or better level. Finally, we describe atomic clock comparison experiments that can probe for a time variation of the fine structure constant, alpha = e(exp 2)/2(pi)hc, at the level of 10(exp -20)/year as predicted in some Grand Unified String Theories.

Investigation of nanosecond pulse dielectric barrier discharges in still air and in transonic flow by optical methods

NASA Astrophysics Data System (ADS)

Peschke, P.; Goekce, S.; Leyland, P.; Ott, P.

2016-01-01

In the present study the interaction of nanosecond pulsed dielectric barrier discharge (ns-DBD) actuators with aerodynamic flow up to transonic velocities was investigated. The primary focus was on the influence of the flow on the discharge and the effects of the discharge itself. In addition, the influence of the ns-DBD on a shock-wave was studied. The aim was to improve the understanding of the plasma-flow interaction, a topic that is not yet fully understood, in particular for ns-DBD. The actuator was integrated in two different models, a NACA 3506 compressor blade profile and a bump geometry at the bottom of the wind tunnel. The effect of the rapid energy deposition close to the discharge was examined with the phase-locked schlieren visualisation technique. Images of the plasma acquired with short exposure times revealed information on the discharge evolution. The results show a significant effect of the flow on the discharge characteristics, in particular due to the drop of static pressure. On the other hand, no significant effect of the ns-DBD on the flow was observed due to unfavourable flow conditions, which underlines the importance of the actuator’s placement.

Implications of electron heating and non-uniformities in a VHF-CCP for sterilization of medical instruments

NASA Astrophysics Data System (ADS)

Stapelmann, Katharina; Fiebrandt, Marcel; Styrnoll, Tim; Baldus, Sabrina; Bibinov, Nikita; Awakowicz, Peter

2015-06-01

A capacitively coupled plasma driven at a frequency of 81.36 MHz from the VHF-band is investigated by means of optical emission spectroscopy (OES) and multipole resonance probe (MRP). The discharge is operated with hydrogen, yielding an electropositive discharge, as well as oxygen, yielding an electronegative discharge, and mixtures of both. Pressure is varied from p=5 Pa to p=25 Pa. Homogeneity of the discharge is investigated by CCD camera recordings as well as spatially resolved multipole resonance probe measurements. The results indicate the presence of electromagnetic edge effects as well as standing wave effects. Furthermore, a largely homogeneous discharge can be achieved with hydrogen as process gas at a pressure of p=5 -10 Pa. With increasing pressure as well as with increasing oxygen content, the discharge appears less homogeneously. The transition from an electropositive to an electronegative discharge leads to a change in electron heating mechanisms, with pronounced local maxima of electron density at the sheath edges. A comparison of OES and MRP results reveal a significant difference in electron density, which can be explained by a non-Maxwellian distribution function of electrons.

Effects of gas temperature in the plasma layer on RONS generation in array-type dielectric barrier discharge at atmospheric pressure

NASA Astrophysics Data System (ADS)

Yoon, Sung-Young; Yi, Changho; Eom, Sangheum; Park, Seungil; Kim, Seong Bong; Ryu, Seungmin; Yoo, Suk Jae

2017-12-01

In this work, we studied the control of plasma-produced species under a fixed gas composition (i.e., ambient air) in a 10 kHz-driven array-type dielectric barrier atmospheric-pressure plasma discharge. Instead of the gas composition, only the gas velocity was controlled. Thus, the plasma-maintenance cost was considerably lower than methods such as external N2 or O2 injection. The plasma-produced species were monitored using Fourier transformed infrared spectroscopy. The discharge properties were measured using a voltage probe, current probe, infrared camera, and optical emission spectroscopy. The results showed that the major plasma products largely depend on the gas temperature in the plasma discharge layer. The gas temperature in the plasma discharge layer was significantly different to the temperature of the ceramic adjacent to the plasma discharge layer, even in the small discharge power density of ˜15 W/cm2 or ˜100 W/cm3. Because the vibrational excitation of N2 was suppressed by the higher gas flow, the major plasma-produced species shifted from NOx in low flow to O3 in high flow.

Characterization of a dielectric barrier discharge in controlled atmosphere

NASA Astrophysics Data System (ADS)

Kogelheide, Friederike; Offerhaus, Björn; Bibinov, Nikita; Bracht, Vera; Smith, Ryan; Lackmann, Jan-Wilm; Awakowicz, Peter; Stapelmann, Katharina; Bimap Team; Aept Team

2016-09-01

Non-thermal atmospheric-pressure plasmas are advantageous for various biomedical applications as they make a contact- and painless therapy possible. Due to the potential medical relevance of such plasma sources further understanding of the chemical and physical impact on biological tissue regarding the efficacy and health-promoting effect is necessary. The knowledge of properties and effects offers the possibility to configure plasmas free of risk for humans. Therefore, tailoring the discharge chemistry in regard to resulting oxidative and nitrosative effects on biological tissue by adjusting different parameters is of growing interest. In order to ensure stable conditions for the characterization of the discharge, the used dielectric barrier discharge was mounted in a vessel. Absolutely calibrated optical emission spectroscopy was carried out to analyze the electron density and the reduced electric field. The rather oxygen-based discharge was tuned towards a more nitrogen-based discharge by adjusting several parameters as reactive nitrogen species are known to promote wound healing. Furthermore, the impact of an ozone-free discharge has to be studied. This work was funded by the German Research Foundation (DFG) with the packet grant PAK 816 `Plasma Cell Interaction in Dermatology'.

Low-flow frequency analyses for streams in west-central Florida

USGS Publications Warehouse

Hammett, K.M.

1985-01-01

The log-Pearson type III distribution was used for defining low-flow frequency at 116 continuous-record streamflow stations in west-central Florida. Frequency distributions were calculated for 1, 3, 7, 14, 30, 60, 90, 120, and 183 consecutive-day periods for recurrence intervals of 2, 5, 10, and 20 years. Discharge measurements at more than 100 low-flow partial-record stations and miscellaneous discharge-measurement stations were correlated with concurrent daily mean discharge at continuous-record stations. Estimates of the 7-day, 2-year; 7-day, 10-year; 30-day, 2-year; and 30-day, 10-year discharges were made for most of the low-flow partial-record and miscellaneous discharge-measurement stations based on those correlations. Multiple linear-regression analysis was used in an attempt to mathematically relate low-flow frequency data to basin characteristics. The resulting equations showed an apparent bias and were considered unsatisfactory for use in estimating low-flow characteristics. Maps of the 7-day, 10-year and 30-day, 10-year low flows are presented. Techniques that can be used to estimate low-flow characteristics at an ungaged site are also provided. (USGS)

32 CFR Appendix B to Part 724 - Oath or Affirmation To Be Administered To Discharge Review Board Members

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 5 2012-07-01 2012-07-01 false Oath or Affirmation To Be Administered To Discharge Review Board Members B Appendix B to Part 724 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Pt. 724, App. B Appendix B to Part 724—Oath or...

Early discontinuation of antiseizure medications in neonates with hypoxic-ischemic encephalopathy.

PubMed

Fitzgerald, Mark P; Kessler, Sudha Kilaru; Abend, Nicholas S

2017-06-01

Neonates with hypoxic-ischemic encephalopathy (HIE) managed with therapeutic hypothermia (TH) often experience acute symptomatic seizures, prompting treatment with antiseizure medications (ASMs). Because the risk of seizure occurrence after hospital discharge is unknown, the optimal ASM treatment duration is unclear. We aimed to determine the risk of seizure occurrence after hospital discharge and the impact of ASM treatment duration on this outcome. We performed a single-center, retrospective study of consecutive neonates with HIE managed with TH who received ASMs for acute symptomatic seizures from June 2010 through December 2014. Neonates were monitored with continuous electroencephalography (EEG) during TH. Follow-up data were available for 59 (82%) of 72 neonates who survived to discharge, with a median follow-up period of 19 months (interquartile range [IQR] 11-25). Acute symptomatic seizures occurred in 35 neonates (59%), including electrographic seizures in 21 neonates (36%). ASMs were continued upon discharge in 17 (49%) of 35 neonates. Seizures occurred in follow-up in four neonates (11%). No patient for whom ASMs were discontinued prior to discharge experienced seizures during the follow-up period. Among neonates with HIE, seizures after hospital discharge were rare in those with acute symptomatic seizures and did not occur in neonates without acute symptomatic seizures. ASM discontinuation prior to discharge did not increase the risk of seizures during the follow-up period, suggesting that ASMs may be discontinued in many neonates prior to discharge. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

32 CFR 724.218 - Limitation-Continuance and Postponements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Limitation-Continuance and Postponements. 724... Limitation—Continuance and Postponements. (a) A continuance of a discharge review hearing may be authorized... continuance is of reasonable duration and is essential to achieving a full and fair hearing. When a proposal...

Optical characteristics and parameters of gas-discharge plasma in a mixture of mercury dibromide vapor with argon

NASA Astrophysics Data System (ADS)

Malinina, A. A.; Malinin, A. N.

2015-03-01

Results are presented from studies of the optical characteristics and parameters of the plasma of a dielectric barrier discharge in a mixture of mercury dibromide vapor with argon—the working medium of an exciplex gas-discharge emitter. It is established that the partial pressures of mercury dibromide vapor and argon at which the average and pulsed emission intensities in the blue—green spectral region (λmax = 502 nm) reach their maximum values are 0.6 and 114.4 kPa, respectively. The electron energy distribution function, the transport characteristics, the specific power spent on the processes involving electrons, the electron density and temperature, and the rate constants for the processes of elastic and inelastic electron scattering from the molecules and atoms of the working mixture are determined by numerical simulation, and their dependences on the reduced electric field strength are analyzed. The rate constant of the process leading to the formation of exciplex mercury monobromide molecules for a reduced electric field of E/ N = 20 Td, at which the maximum emission intensity in the blue—green spectral region was observed in this experiment, is found to be 8.1 × 10-15 m3/s.

Capacitively coupled hydrogen plasmas sustained by tailored voltage waveforms: excitation dynamics and ion flux asymmetry

DOE PAGES

Bruneau, B.; Diomede, P.; Economou, D. J.; ...

2016-06-08

Parallel plate capacitively coupled plasmas in hydrogen at relatively high pressure (~1 Torr) are excited with tailored voltage waveforms containing up to five frequencies. Predictions of a hybrid model combining a particle-in-cell simulation with Monte Carlo collisions and a fluid model are compared to phase resolved optical emission spectroscopy measurements, yielding information on the dynamics of the excitation rate in these discharges. When the discharge is excited with amplitude asymmetric waveforms, the discharge becomes electrically asymmetric, with different ion energies at each of the two electrodes. Unexpectedly, large differences in themore » $$\\text{H}_{2}^{+}$$ fluxes to each of the two electrodes are caused by the different $$\\text{H}_{3}^{+}$$ energies. When the discharge is excited with slope asymmetric waveforms, only weak electrical asymmetry of the discharge is observed. In this case, electron power absorption due to fast sheath expansion at one electrode is balanced by electron power absorption at the opposite electrode due to a strong electric field reversal.« less

Characteristics of Partial Discharge and Ozone Generation for Twisted-pair of Enameled Wires under High-repetitive Impulse Voltage Application

NASA Astrophysics Data System (ADS)

Kanazawa, Seiji; Enokizono, Masato; Shibakita, Toshihide; Umehara, Eiji; Toshimitsu, Jun; Ninomiya, Shinji; Taniguchi, Hideki; Abe, Yukari

In recent years, inverter drive machines such as a hybrid vehicle and an electric vehicle are operated under high voltage pulse with high repetition rate. In this case, inverter surge is generated and affected the machine operation. Especially, the enameled wire of a motor is deteriorated due to the partial discharge (PD) and finally breakdown of the wire will occur. In order to investigate a PD on a resistant enameled wire, characteristics of PD in the twisted pair sample under bipolar repetitive impulse voltages are investigated experimentally. The relationship between the applied voltage and discharge current was measured at PD inception and extinction, and we estimated the repetitive PD inception and extinction voltages experimentally. The corresponding optical emission of the discharge was also observed by using an ICCD camera. Furthermore, ozone concentration due to the discharge was measured during the life-time test of the resistant enameled wires from a working environmental point of view.

Fast optical and electrical diagnostics of pulsed spark discharges in different gap geometries

NASA Astrophysics Data System (ADS)

Höft, Hans; Huiskamp, Tom; Kettlitz, Manfred

2016-09-01

Spark discharges in different electrode configurations and with various electrode materials were ignited in air at atmospheric pressure using a custom build pulse charger with 1 μs voltage rise time (up to 28 kV) in single shot operation. Fast voltage and current measurements were combined with iCCD imaging with high spatial resolution (better than 10 μm) on pin-to-pin, pin-to-half-sphere and symmetrical half-sphere tungsten electrodes and symmetrical half-sphere brass electrodes for electrode gaps of 0.1 to 0.7 mm. Breakdown voltages, consumed electrical energies and the discharge emission structures as well as the discharge diameters were obtained. Because of the synchronization of the electrical measurements and the iCCD imaging (i.e. one complete data set for every shot), it was possible to estimate the current density and the change of the discharge pattern, such as single or multiple channels, for all cases. EU funding under Grant No 316216 (PlasmaShape).

Influence of humidity on the characteristics of positive corona discharge in air

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

Xu, Pengfei, E-mail: xpftsh@126.com; Zhang, Bo, E-mail: shizbcn@mail.tsinghua.edu.cn; Chen, Shuiming, E-mail: chensm@tsinghua.edu.cn

Detailed positive corona discharge characteristics, such as the corona onset voltage, pulse amplitude, repetition frequency, average corona current, rise time, and half-wave time, are systematically studied under different air humidity with a single artificial defect electrode. The experimental results indicate that the pulse amplitude decreases with the increase of air humidity; meanwhile, the repetition frequency increases as the air humidity increases. This phenomenon is different from that of negative corona discharge. Therefore, to have an insight into the mechanism of humidity influence on positive corona discharge, a positive corona discharge model based on the continuity equations is utilized. The simulationsmore » present a dynamic development of positive corona discharge and, meanwhile, reveal the humidity influence on positive corona discharge.« less

Cost efficient environmental survey paths for detecting continuous tracer discharges

NASA Astrophysics Data System (ADS)

Alendal, G.

2017-07-01

Designing monitoring programs for detecting potential tracer discharges from unknown locations is challenging. The high variability of the environment may camouflage the anticipated anisotropic signal from a discharge, and there are a number of discharge scenarios. Monitoring operations may also be costly, constraining the number of measurements taken. By assuming that a discharge is active, and a prior belief on the most likely seep location, a method that uses Bayes' theorem combined with discharge footprint predictions is used to update the probability map. Measurement locations with highest reduction in the overall probability of a discharge to be active can be identified. The relative cost between reallocating and measurements can be taken into account. Three different strategies are suggested to enable cost efficient paths for autonomous vessels.

Performance of a CW double electric discharge for supersonic CO lasers

NASA Technical Reports Server (NTRS)

Stanton, A. C.; Hanson, R. K.; Mitchner, M.

1980-01-01

The results of an experimental investigation of a CW double discharge in supersonic CO mixtures are reported. Stable discharges in CO/N2 and CO/Ar mixtures, with a maximum energy loading of 0.5 eV/CO molecule, were achieved in a small-scale continuous-flow supersonic channel. Detailed measurements of the discharge characteristics were performed, including electrostatic probe measurements of floating potential and electron number density and spectroscopic measurements of the CO vibrational population distributions. The results of these measurements indicate that the vibrational excitation efficiency of the discharge is approximately 60%, for moderate levels of main discharge current. These experiments, on a small scale, demonstrate that the double-discharge scheme provides adequate vibrational energy loading for efficient CO laser operation under CW supersonic flow conditions.

[Influence of WeChat platform on the compliance of continuous treatment of scar in adult burn patients].

PubMed

Wang, F; Zhang, H L

2018-03-20

Objective: To explore influence of the WeChat platform on the compliance of continuous treatment of scar in adult burn patients. Methods: A total of 124 adult burn patients, conforming to the study criteria, admitted in the Department of Burns of our hospital from January 2015 to January 2016 were divided into WeChat group ( n =63) and control group ( n =61) according to the random number table. Patients in control group only received regular discharging rehabilitation guide, while patients in WeChat group received regular discharging rehabilitation guide and joined WeChat platform after being discharged from hospital. Through pushing rehabilitation plan and rehabilitation related knowledge, organizing support discussion of burn patients, answering the patients' questions, members of WeChat platform intervention group conducted continuous treatment for 6 months on patients of WeChat group. The compliance of functional exercise of patients in two groups in one week before discharge and 3 and 6 months after discharge was evaluated by using the self-made functional exercise compliance log sheet. The compliance of using anti-scar drug and appliance of patients in two groups in 3 and 6 months after discharge was evaluated by using self-made anti-scar drug and appliance usage log sheets. Data were processed with chi-square test, independent sample t test, non-parametric rank sum test of independent sample, and Wilcoxon rank sum test. Results: (1) The compliance ratio of functional exercise of patients in WeChat group (95.24%, 60/63) was close to 93.44% (57/61) in control group in one week before discharge ( χ (2)=0.188, P >0.05). The compliance ratios of functional exercise of patients in WeChat group were respectively 93.65% (59/63) and 87.30% (55/63) in 3 and 6 months after discharge, which were higher than 68.85% (42/61) and 65.57% (40/61) in control group ( χ (2)=12.615, 8.166, P <0.01). (2) The compliance of using anti-scar drug of patients in WeChat group was significantly better than that in control group in 3 and 6 months after discharge ( Z =-4.150, -4.563, P <0.01). (3) The compliance of using anti-scar appliance of patients in WeChat group in 3 and 6 months after discharge was obviously better than that in control group ( Z =-4.242, -4.301, P <0.01). Conclusions: By using WeChat platform to provide guide for scar rehabilitation continuous treatment, adult burn patients have better compliance to functional exercise and usage of anti-scar drug and appliance.

Modeling terrestrial gamma ray flashes produced by relativistic feedback discharges

NASA Astrophysics Data System (ADS)

Liu, Ningyu; Dwyer, Joseph R.

2013-05-01

This paper reports a modeling study of terrestrial gamma ray flashes (TGFs) produced by relativistic feedback discharges. Terrestrial gamma ray flashes are intense energetic radiation originating from the Earth's atmosphere that has been observed by spacecraft. They are produced by bremsstrahlung interactions of energetic electrons, known as runaway electrons, with air atoms. An efficient physical mechanism for producing large fluxes of the runaway electrons to make the TGFs is the relativistic feedback discharge, where seed runaway electrons are generated by positrons and X-rays, products of the discharge itself. Once the relativistic feedback discharge becomes self-sustaining, an exponentially increasing number of relativistic electron avalanches propagate through the same high-field region inside the thundercloud until the electric field is partially discharged by the ionization created by the discharge. The modeling results indicate that the durations of the TGF pulses produced by the relativistic feedback discharge vary from tens of microseconds to several milliseconds, encompassing all durations of the TGFs observed so far. In addition, when a sufficiently large potential difference is available in thunderclouds, a self-propagating discharge known as the relativistic feedback streamer can be formed, which propagates like a conventional positive streamer. For the relativistic feedback streamer, the positive feedback mechanism of runaway electron production by the positrons and X-rays plays a similar role as the photoionization for the conventional positive streamer. The simulation results of the relativistic feedback streamer show that a sequence of TGF pulses with varying durations can be produced by the streamer. The relativistic streamer may initially propagate with a pulsed manner and turn into a continuous propagation mode at a later stage. Milliseconds long TGF pulses can be produced by the feedback streamer during its continuous propagation. However, the continuous propagation of the streamer tends to be unstable, because it does not expand like the conventional positive streamer. Its head electric field continues to increase and can reach half of the conventional breakdown threshold field, which results in an ion density of 3- 10×1014m-3 in the channel immediately following the head. The spatial width of the high field region in the streamer head is about 100 m and the streamer speed is about 5×105 m/s. As a result, conventional positive streamers can be initiated from thundercloud hydrometeors or inhomogeneities of enhanced conductivities of millimeter sizes in the relativistic feedback streamer head and the positive streamers may further result in the formation of leaders. In addition, a relativistic feedback streamer can result in a charge moment change of several tens of coulomb-kilometers in a few tens of milliseconds, indicating that the relativistic feedback discharge process could be an important component for thundercloud charge dynamics.

An Overview of Three-year JEM-GLIMS Nadir Observations of Lightning and TLEs

NASA Astrophysics Data System (ADS)

Sato, M.; Ushio, T.; Morimoto, T.; Adachi, T.; Kikuchi, H.; Suzuki, M.; Yamazaki, A.; Takahashi, Y.; Inan, U.; Linscott, I.; Hobara, Y.

2015-12-01

JEM-GLIMS nadir observations of lightning and TLEs at the ISS started from November 2012 and successfully ended on August 2015. For three-year observation period, JEM-GLIMS succeeded in detecting over 8,000 lightning events and 670 TLEs. The detected optical emissions of sprites showed clear horizontal displacement with the range of 10-20 km from the peak location of the +CG emissions and from the +CG locations detected by NLDN and WWLLN. Using VITF electric field waveform data, source locations of VHF pulses excited by the parent CG discharges are estimated. It is found that the possible VHF source locations were mostly located within the area of the parent lightning emissions. These facts may imply that the center region of the neutralized charge by CG discharges in the thundercloud located near the return stroke point and that the some seed conditions were established in advance at the sprite location before the occurrence of sprites. The global occurrence distributions and rates of lightning discharges and TLEs are also estimated. The estimated mean global occurrence rate of lightning discharges is ~1.5 events/s, which is smaller number than that derived from MicroLab-1/OTD and TRMM/LIS measurements. This may be originated in the fact that JEM-GLISM detected only intense lightning optical events due to the high threshold level for the event triggering. To the contrary, the estimated mean global occurrence rate of TLEs is ~9.8 events/min, which is two times higher than the ISUAL result. It is likely that JEM-GLIMS could detect dimmer optical emissions of TLEs than ISUAL since the distance between the JEM-GLIMS instruments and TLEs is much closer. At the presentation, we will summarize the results derived from three-year JEM-GLIMS nadir observations. We will discuss possible occurrence conditions of sprites, properties of global occurrence rates of lightning and TLEs, and their LT dependences more in detail.

Longitudinal Plasmoid in High-Speed Vortex Gas Flow Created by Capacity HF Discharge

DTIC Science & Technology

2010-10-28

interferometer with high space resolution, PIV method, FTIR spectrometer, optical spectrometer, pressure sensors with high time resolution, IR pyrometer and...of strong LP-vortex interaction. Intensive acoustic waves are created by CHFD in swirl flow in this regime. 38. Study of control of a longitudinal...quartz tube, 4- HF ball electrode, 5- Tesla’s transformer, 6- microwave interferometer, 7- video camera, 8-optical pyrometer , 9-pressure sensor, 10

Reproducing continuous radio blackout using glow discharge plasma

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

Xie, Kai; Li, Xiaoping; Liu, Donglin

2013-10-15

A novel plasma generator is described that offers large-scale, continuous, non-magnetized plasma with a 30-cm-diameter hollow structure, which provides a path for an electromagnetic wave. The plasma is excited by a low-pressure glow discharge, with varying electron densities ranging from 10{sup 9} to 2.5 × 10{sup 11} cm{sup −3}. An electromagnetic wave propagation experiment reproduced a continuous radio blackout in UHF-, L-, and S-bands. The results are consistent with theoretical expectations. The proposed method is suitable in simulating a plasma sheath, and in researching communications, navigation, electromagnetic mitigations, and antenna compensation in plasma sheaths.

Analytical and Experimental Study to Improve Computer Models for Mixing and Dilution of Soluble Hazardous Chemicals.

DTIC Science & Technology

1982-08-01

Trajectory and Concentration of Various Plumes 59 IV.2 Tank and Cargo Geometry Assumed for Discharge Rate Calculation Using HACS Venting Rate Model 61...Discharge Rate Calculation Using HACS Venting Rate Model 62 IV.4 Original Test Plan for Validation of the Continuous Spill Model 66 IV.5 Final Test Plan...at t= 0. exEyEz = turbulent diffusivities. p = water density. Pc = chemical density. Symbols Used Only in Continuous-Spill Models for a Steady River b

Detecting salt deposition on a wind turbine blade using laser induced breakdown spectroscopy technique

NASA Astrophysics Data System (ADS)

Sathiesh Kumar, V.; Vasa, Nilesh J.; Sarathi, R.

2013-07-01

The study of pollution performance on a wind turbine blade due to lightning is important, as it can cause major damage to wind turbine blades. In the present work, optical emission spectroscopy (OES) technique is used to understand the influence of pollutant deposited on a wind turbine blade in an off-shore environment. A methodical experimental study was carried out by adopting IEC 60507 standards, and it was observed that the lightning discharge propagates at the interface between the pollutant and the glass fiber reinforced plastic (Material used in manufacturing of wind turbine blades). In addition, as a diagnostic condition monitoring technique, laser-induced breakdown spectroscopy (LIBS) is proposed and demonstrated to rank the severity of pollutant on the wind turbine blades from a remote area. Optical emission spectra observed during surface discharge process induced by lightning impulse voltage is in agreement with the spectra observed during LIBS.

Optical properties of polyimides films treated by nanosecond pulsed electrical discharges in water

NASA Astrophysics Data System (ADS)

Sava, Ion; Kruth, Angela; Kolb, Juergen F.; Miron, Camelia

2018-01-01

Fluorinated polyimide films containing cobalt chloride based on hexafluoroisopropylidenediphthalic dianhydride and 4,4‧-diamino-3,3‧-dimethyl diphenylmethane were treated by nanosecond pulsed electrical discharges generated in distilled water. The polyimide films have been characterized by Fourier transform infrared (FTIR) spectra and contact angle measurements, optical transmission spectroscopy, and fluorescence spectroscopy. Significant changes in some intrinsic fluorescence features, such as the intensity and position of the emission peak, have been observed during exposure to water plasma. These effects have been considered to correlate with the development of specific chemical interactions between the liquid and the macromolecules, including the formation of hydrogen bridges. A slight increase in surface hydrophobicity was observed after plasma treatment. FTIR spectra showed a decrease in the intensity of the absorption band and an opening of the imide ring, depending on the treatment time.

Analysis and design of ion thrusters for large space systems

NASA Technical Reports Server (NTRS)

James, E. L.

1980-01-01

This study undertakes the analysis and conceptual design of a 0.5 Newton electrostatic ion thruster suitable for use on large space system missions in the next decade. Either argon or xenon gas shall be used as propellant. A 50 cm diameter discharge chamber was selected to meet stipulated performance goals. The discharge plasma is contained at the boundary by a periodic structure of alternating permanent magnets generating a series of line cusps. Anode strips between the magnets collect Maxwellian electrons generated by a central cathode. Ion extraction utilizes either two or three grid optics at the user's choice. An extensive analysis was undertaken to investigate optics behavior in the high power environment of this large thruster. A plasma bridge neutralizer operating on inert gas provides charge neutralizing electrons to complete the design. The resulting conceptual thruster and the necessary power management and control requirements are described.

Optical discharge with absorption of repetitive CO{sub 2} laser pulses in supersonic air flow: wave structure and condition of a quasi-steady state

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

Bobarykina, T A; Malov, A N; Orishich, A M

We report a study of the wave structure formed by an optical discharge plasma upon the absorption of repetitively pulsed CO{sub 2} laser radiation in a supersonic (M = 1.36) air flow. Experimental data are presented on the configuration of the head shock wave and the geometry and characteristic dimensions of breakdown regions behind a laser plasma pulsating in the flow at a frequency of up to 150 kHz. The data are compared to calculation in a point explosion model with allowance for counterpressure, which makes it possible to identify the relationship between laser radiation and supersonic flow parameters thatmore » ensures quasisteady- state energy delivery and is necessary for extending the possibilities of controlling the structure of supersonic flows. (interaction of laser radiation with matter)« less

40 CFR 430.65 - New source performance standards (NSPS).

Code of Federal Regulations, 2014 CFR

2014-07-01

... dischargers, concentration limitations (mg/l) shall apply, where provided. Concentration limitations will only apply to non-continuous dischargers. Only facilities where chlorophenolic-containing biocides are used... chlorophenolic-containing biocides must certify to the permit-issuing authority that they are not using these...

40 CFR 430.15 - New source performance standards (NSPS).

Code of Federal Regulations, 2012 CFR

2012-07-01

... dischargers, concentration limitations (mg/l) shall apply, where provided. Concentration limitations will only apply to non-continuous dischargers. Only facilities where chlorophenolic-containing biocides are used... chlorophenolic-containing biocides must certify to the permit-issuing authority that they are not using these...

40 CFR 430.45 - New source performance standards (NSPS).

Code of Federal Regulations, 2013 CFR

2013-07-01

... dischargers, concentration limitations (mg/l) shall apply, where provided. Concentration limitations will only apply to non-continuous dischargers. Only facilities where chlorophenolic-containing biocides are used... chlorophenolic-containing biocides must certify to the permit-issuing authority that they are not using these...

40 CFR 430.65 - New source performance standards (NSPS).

Code of Federal Regulations, 2013 CFR

2013-07-01

... dischargers, concentration limitations (mg/l) shall apply, where provided. Concentration limitations will only apply to non-continuous dischargers. Only facilities where chlorophenolic-containing biocides are used... chlorophenolic-containing biocides must certify to the permit-issuing authority that they are not using these...

40 CFR 430.15 - New source performance standards (NSPS).

Code of Federal Regulations, 2013 CFR

2013-07-01

... dischargers, concentration limitations (mg/l) shall apply, where provided. Concentration limitations will only apply to non-continuous dischargers. Only facilities where chlorophenolic-containing biocides are used... chlorophenolic-containing biocides must certify to the permit-issuing authority that they are not using these...

40 CFR 430.15 - New source performance standards (NSPS).

Code of Federal Regulations, 2014 CFR

2014-07-01

... dischargers, concentration limitations (mg/l) shall apply, where provided. Concentration limitations will only apply to non-continuous dischargers. Only facilities where chlorophenolic-containing biocides are used... chlorophenolic-containing biocides must certify to the permit-issuing authority that they are not using these...

40 CFR 430.35 - New source performance standards (NSPS).

Code of Federal Regulations, 2013 CFR

2013-07-01

... dischargers, concentration limitations (mg/l) shall apply, where provided. Concentration limitations will only apply to non-continuous dischargers. Only facilities where chlorophenolic-containing biocides are used... chlorophenolic-containing biocides must certify to the permit-issuing authority that they are not using these...

40 CFR 430.45 - New source performance standards (NSPS).

Code of Federal Regulations, 2014 CFR

2014-07-01

... dischargers, concentration limitations (mg/l) shall apply, where provided. Concentration limitations will only apply to non-continuous dischargers. Only facilities where chlorophenolic-containing biocides are used... chlorophenolic-containing biocides must certify to the permit-issuing authority that they are not using these...

40 CFR 430.35 - New source performance standards (NSPS).

Code of Federal Regulations, 2014 CFR

2014-07-01

... dischargers, concentration limitations (mg/l) shall apply, where provided. Concentration limitations will only apply to non-continuous dischargers. Only facilities where chlorophenolic-containing biocides are used... chlorophenolic-containing biocides must certify to the permit-issuing authority that they are not using these...

32 CFR 724.701 - Composition.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Organization of the Naval Discharge Review Board § 724.701 Composition. The NDRB acting in plenary review session shall be composed of five members. Normally the members shall be career military officers...

40 CFR 461.1 - Applicability.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY General Provisions § 461.1 Applicability. This part applies to any battery manufacturing plant that discharges or may discharge a pollutant to waters of the United States or that introduces pollutants to a publicly owned treatment works. Battery manufacturing...

40 CFR 461.1 - Applicability.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY General Provisions § 461.1 Applicability. This part applies to any battery manufacturing plant that discharges or may discharge a pollutant to waters of the United States or that introduces pollutants to a publicly owned treatment works. Battery manufacturing...

40 CFR 461.1 - Applicability.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY General Provisions § 461.1 Applicability. This part applies to any battery manufacturing plant that discharges or may discharge a pollutant to waters of the United States or that introduces pollutants to a publicly owned treatment works. Battery manufacturing...

32 CFR 724.215 - Military representation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Military representation. 724.215 Section 724.215 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Authority/Policy for Departmental Discharge Review § 724.215 Military representation. Military...

Diagnosis of a short-pulse dielectric barrier discharge at atmospheric pressure in helium with hydrogen-methane admixtures

NASA Astrophysics Data System (ADS)

Nastuta, A. V.; Pohoata, V.; Mihaila, I.; Topala, I.

2018-04-01

In this study, we present results from electrical, optical, and spectroscopic diagnosis of a short-pulse (250 ns) high-power impulse (up to 11 kW) dielectric barrier discharge at atmospheric pressure running in a helium/helium-hydrogen/helium-hydrogen-methane gas mixture. This plasma source is able to generate up to 20 cm3 of plasma volume, pulsed in kilohertz range. The plasma spatio-temporal dynamics are found to be developed in three distinct phases. All the experimental observations reveal a similar dynamic to medium power microsecond barrier discharges, although the power per pulse and current density are up to two orders of magnitude higher than the case of microsecond barrier discharges. This might open the possibility for new applications in the field of gas or surface processing, and even life science. These devices can be used in laboratory experiments relevant for molecular astrophysics.

Influence of shock waves from plasma actuators on transonic and supersonic airflow

NASA Astrophysics Data System (ADS)

Mursenkova, I. V.; Znamenskaya, I. A.; Lutsky, A. E.

2018-03-01

This paper presents experimental and numerical investigations of high-current sliding surface discharges of nanosecond duration and their effect on high-speed flow as plasma actuators in a shock tube. This study deals with the effectiveness of a sliding surface discharge at low and medium air pressure. Results cover the electrical characteristics of the discharge and optical visualization of the discharge and high-speed post-discharge flow. A sliding surface discharge is first studied in quiescent air conditions and then in high-speed flow, being initiated in the boundary layer at a transverse flow velocity of 50-950 m s-1 behind a flat shock wave in air of density 0.04-0.45 kg m-3. The discharge is powered by a pulse voltage of 25-30 kV and the electric current is ~0.5 kA. Shadow imaging and particle image velocimetry (PIV) are used to measure the flow field parameters after the pulse surface discharge. Shadow imaging reveals shock waves originating from the channels of the discharge configurations. PIV is used to measure the velocity field resulting from the discharge in quiescent air and to determine the homogeneity of energy release along the sliding discharge channel. Semicylindrical shock waves from the channels of the sliding discharge have an initial velocity of more than 600 m s-1. The shock-wave configuration floats in the flow along the streamlined surface. Numerical simulation based on the equations of hydrodynamics matched with the experiment showed that 25%-50% of the discharge energy is instantly transformed into heat energy in a high-speed airflow, leading to the formation of shock waves. This energy is comparable to the flow enthalpy and can result in significant modification of the boundary layer and the entire flow.

Airborne atmospheric electricity experiments

NASA Technical Reports Server (NTRS)

Blakeslee, R. J.

1985-01-01

During the 1984 U2 spring flight program, lightning spectra were measured in the wavelengths from 380 nm to 900 nm with a temporal resolution of 5 ms. With this capability, researchers simultaneously acquired both visible near-infrared lightning spectra on a pulse to pulse basis, so that the spectral variability within a flash, as well as flash to flash variations, can be studied. Preliminary results suggest that important variations do occur, particularly in the strengths of the hydrogen and singly ionized nitrogen emission lines. Also, the results have revealed significant differences in the integrated energy distributions between the lightning spectra measured above clouds and the spectral measurements of cloud-to-ground lightning made at the ground. In particular, the ratio of the energy in the near-IR to that in the visible is around 1 to 2 for cloud top spectra versus about 1/3 for surface observations. Detailed analyses of the 1984 lightning spectral data is being conducted. This data should provide improved understanding about the optical transmission properties of thunderclouds and the physics of the lightning discharge process. Efforts continue on developing and testing background signal removal algorithms using U2 spectometer and optical array sensor day-flight data sets. The goal of this research is to develop an algorithm satisfying Lightning Mapper Sensor requirements.

Optical emission spectroscopy of point-plane corona and back-corona discharges in air

NASA Astrophysics Data System (ADS)

Czech, T.; Sobczyk, A. T.; Jaworek, A.

2011-12-01

Results of spectroscopic investigations and current-voltage characteristics of corona discharge and back discharge on fly-ash layer, generated in point-plane electrode geometry in air at atmospheric pressure are presented in the paper. The characteristics of both discharges are similar but differ in the current and voltage ranges of all the discharge forms distinguished during the experiments. Three forms of back discharge, for positive and negative polarity, were investigated: glow, streamer and low-current back-arc. In order to characterize ionisation and excitation processes in back discharge, the emission spectra were measured and compared with those obtained for normal corona discharge generated in the same electrode configuration but with fly ash layer removed. The emission spectra were measured in two discharge zones: near the tip of needle electrode and near the plate. Visual forms of the discharge were recorded with digital camera and referred to current-voltage characteristics and emission spectra. The measurements have shown that spectral lines emitted by back discharge depend on the form of discharge and the discharge current. From the comparison of the spectral lines of back and normal discharges an effect of fly ash layer on the discharge morphology can be determined. The recorded emission spectra formed by ionised gas and plasma near the needle electrode and fly ash layer are different. It should be noted that in back arc emission, spectral lines of fly ash layer components can be distinguished. On the other hand, in needle zone, the emission of high intensity N2 second positive system and NO γ lines can be noticed. Regardless of these gaseous lines, also atomic lines of dust layer were present in the spectrum. The differences in spectra of back discharge for positive and negative polarities of the needle electrode have been explained by considering the kind of ions generated in the crater in fly ash layer. The aim of these studies is to better understand the discharge processes encountered in electrostatic precipitators.

A High-Speed Spectroscopy System for Observing Lightning and Transient Luminous Events

NASA Astrophysics Data System (ADS)

Boggs, L.; Liu, N.; Austin, M.; Aguirre, F.; Tilles, J.; Nag, A.; Lazarus, S. M.; Rassoul, H.

2017-12-01

Here we present a high-speed spectroscopy system that can be used to record atmospheric electrical discharges, including lightning and transient luminous events. The system consists of a Phantom V1210 high-speed camera, a Volume Phase Holographic (VPH) grism, an optional optical slit, and lenses. The spectrograph has the capability to record videos at speeds of 200,000 frames per second and has an effective wavelength band of 550-775 nm for the first order spectra. When the slit is used, the system has a spectral resolution of about 0.25 nm per pixel. We have constructed a durable enclosure made of heavy duty aluminum to house the high-speed spectrograph. It has two fans for continuous air flow and a removable tray to mount the spectrograph components. In addition, a Watec video camera (30 frames per second) is attached to the top of the enclosure to provide a scene view. A heavy duty Pelco pan/tilt motor is used to position the enclosure and can be controlled remotely through a Rasperry Pi computer. An observation campaign has been conducted during the summer and fall of 2017 at the Florida Institute of Technology. Several close cloud-to-ground discharges were recorded at 57,000 frames per second. The spectrum of a downward stepped negative leader and a positive cloud-to-ground return stroke will be reported on.

Pulse-Modulated Radio-Frequency Alternating-Current-Driven Atmospheric-Pressure Glow Discharge for Continuous-Flow Synthesis of Silver Nanoparticles and Evaluation of Their Cytotoxicity toward Human Melanoma Cells.

PubMed

Dzimitrowicz, Anna; Bielawska-Pohl, Aleksandra; diCenzo, George C; Jamroz, Piotr; Macioszczyk, Jan; Klimczak, Aleksandra; Pohl, Pawel

2018-06-02

An innovative and environmentally friendly method for the synthesis of size-controlled silver nanoparticles (AgNPs) is presented. Pectin-stabilized AgNPs were synthesized in a plasma-reaction system in which pulse-modulated radio-frequency atmospheric-pressure glow discharge (pm-rf-APGD) was operated in contact with a flowing liquid electrode. The use of pm-rf-APGD allows for better control of the size of AgNPs and their stability and monodispersity. AgNPs synthesized under defined operating conditions exhibited average sizes of 41.62 ± 12.08 nm and 10.38 ± 4.56 nm, as determined by dynamic light scattering and transmission electron microscopy (TEM), respectively. Energy-dispersive X-ray spectroscopy (EDS) confirmed that the nanoparticles were composed of metallic Ag. Furthermore, the ξ-potential of the AgNPs was shown to be -43.11 ± 0.96 mV, which will facilitate their application in biological systems. Between 70% and 90% of the cancerous cells of the human melanoma Hs 294T cell line underwent necrosis following treatment with the synthesized AgNPs. Furthermore, optical emission spectrometry (OES) identified reactive species, such as NO, NH, N₂, O, and H, as pm-rf-APGD produced compounds that may be involved in the reduction of the Ag(I) ions.

Radiation effects on ETFE polymer exposed to glow discharge

NASA Astrophysics Data System (ADS)

Minamisawa, Renato Amaral; Abidzina, Volha; de Almeida, Adelaide; Budak, Satilmis; Tereshko, I.; Elkin, I.; Ila, Daryush

2007-08-01

The polymer ethylenetetrafluoroethylene (ETFE) is composed of alternating ethylene and tetrafluoroethylene segments. Because it has applications in areas such as medical physics and industrial coatings, there is a great interest in surface modification studies of ETFE polymer. When this material is exposed to ionizing radiation it suffers damage that depends on the type, energy and intensity of the irradiation. In order to determine the radiation damage mechanism from exposure to low voltage plasma, ETFE films were exposed to residual gas plasma in glow discharge regime to a fluence of 2 × 1017 ions/cm2. Irradiated films were analyzed with optical absorption photospectrometry, Fourier transform infrared (FTIR) and Raman spectroscopy to determine the chemical nature of the structural changes caused by low energy glow discharge.

OH Production Enhancement in Bubbling Pulsed Discharges

NASA Astrophysics Data System (ADS)

Lungu, Cristian P.; Porosnicu, Corneliu; Jepu, Ionut; Chiru, Petrica; Zaroschi, Valentin; Lungu, Ana M.; Saito, Nagahiro; Bratescu, Maria; Takai, Osamu; Velea, Theodor; Predica, Vasile

2010-10-01

The generation of active species, such as H2O2, O*, OH*, HO2*, O3, N2*, etc, produced in aqueous solutions by HV pulsed discharges was studied in order to find the most efficient way in waste water treatment taking into account that these species are almost stronger oxidizers than ozone. Plasma was generated inside gas bubbles formed by the argon, air and oxygen gas flow between the special designed electrodes. The pulse width and pulse frequency influence was studied in order to increase the efficiency of the OH active species formation. The produced active species were investigated by optical emission spectroscopy and correlated with electrical parameters of the discharges (frequency, pulse width, amplitude, and rise and decay time).

32 CFR 724.603 - Functions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Functions. 724.603 Section 724.603 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Naval Discharge Review Board Mission and Functions § 724.603 Functions. (a) Meet as frequently as...

46 CFR 56.50-20 - Pressure relief piping.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND... authorized by the Marine Safety Center. (b) Discharge lines (reproduces 122.6.2(d)). Discharge lines from pressure-relieving safety devices shall be designed to facilitate drainage. (c) Stop valves. Stop valves...

46 CFR 56.50-20 - Pressure relief piping.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND... authorized by the Marine Safety Center. (b) Discharge lines (reproduces 122.6.2(d)). Discharge lines from pressure-relieving safety devices shall be designed to facilitate drainage. (c) Stop valves. Stop valves...

32 CFR 724.702 - Executive management.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 5 2012-07-01 2012-07-01 false Executive management. 724.702 Section 724.702 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Organization of the Naval Discharge Review Board § 724.702 Executive management. The...

32 CFR 724.702 - Executive management.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 5 2013-07-01 2013-07-01 false Executive management. 724.702 Section 724.702 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Organization of the Naval Discharge Review Board § 724.702 Executive management. The...

32 CFR 724.702 - Executive management.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 32 National Defense 5 2014-07-01 2014-07-01 false Executive management. 724.702 Section 724.702 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Organization of the Naval Discharge Review Board § 724.702 Executive management. The...

32 CFR 724.702 - Executive management.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Executive management. 724.702 Section 724.702 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Organization of the Naval Discharge Review Board § 724.702 Executive management. The...

46 CFR 167.20-15 - Scupper, sanitary and similar discharges.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Section 167.20-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Hull Requirements, Construction and Arrangement of Nautical School Ships § 167.20-15 Scupper, sanitary and similar discharges. (a) All scupper, sanitary, and other similar...

46 CFR 167.20-15 - Scupper, sanitary and similar discharges.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Section 167.20-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Hull Requirements, Construction and Arrangement of Nautical School Ships § 167.20-15 Scupper, sanitary and similar discharges. (a) All scupper, sanitary, and other similar...

46 CFR 167.20-15 - Scupper, sanitary and similar discharges.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Section 167.20-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Hull Requirements, Construction and Arrangement of Nautical School Ships § 167.20-15 Scupper, sanitary and similar discharges. (a) All scupper, sanitary, and other similar...

46 CFR 167.20-15 - Scupper, sanitary and similar discharges.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Section 167.20-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Hull Requirements, Construction and Arrangement of Nautical School Ships § 167.20-15 Scupper, sanitary and similar discharges. (a) All scupper, sanitary, and other similar...