Sample records for inductively coupled plasma

  1. Inductively coupled helium plasma torch

    DOE Patents [OSTI]

    Montaser, Akbar (Potomac, MD); Chan, Shi-Kit (Washington, DC); Van Hoven, Raymond L. (Alexandria, VA)

    1989-01-01T23:59:59.000Z

    An inductively coupled plasma torch including a base member, a plasma tube and a threaded insert member within the plasma tube for directing the plasma gas in a tangential flow pattern. The design of the torch eliminates the need for a separate coolant gas tube. The torch can be readily assembled and disassembled with a high degree of alignment accuracy.

  2. Mobile inductively coupled plasma system

    DOE Patents [OSTI]

    D'Silva, Arthur P. (Ames, IA); Jaselskis, Edward J. (Ames, IA)

    1999-03-30T23:59:59.000Z

    A system for sampling and analyzing a material located at a hazardous site. A laser located remote from the hazardous site is connected to an optical fiber, which directs laser radiation proximate the material at the hazardous site. The laser radiation abates a sample of the material. An inductively coupled plasma is located remotely from the material. An aerosol transport system carries the ablated particles to a plasma, where they are dissociated, atomized and excited to provide characteristic optical reduction of the elemental constituents of the sample. An optical spectrometer is located remotely from the site. A second optical fiber is connected to the optical spectrometer at one end and the plasma source at the other end to carry the optical radiation from the plasma source to the spectrometer.

  3. Mobile inductively coupled plasma system

    DOE Patents [OSTI]

    D`Silva, A.P.; Jaselskis, E.J.

    1999-03-30T23:59:59.000Z

    A system is described for sampling and analyzing a material located at a hazardous site. A laser located remotely from the hazardous site is connected to an optical fiber, which directs laser radiation proximate the material at the hazardous site. The laser radiation abates a sample of the material. An inductively coupled plasma is located remotely from the material. An aerosol transport system carries the ablated particles to a plasma, where they are dissociated, atomized and excited to provide characteristic optical reduction of the elemental constituents of the sample. An optical spectrometer is located remotely from the site. A second optical fiber is connected to the optical spectrometer at one end and the plasma source at the other end to carry the optical radiation from the plasma source to the spectrometer. 10 figs.

  4. Inductively coupled plasma chemistry examinations with visible acousto-optic tunable filter hyperspectral imaging{

    E-Print Network [OSTI]

    Duffin, Kirk

    to be a powerful tool for plasma chemistry research. Introduction Inductively coupled plasma optical emission

  5. Miniaturization of Inductively Coupled Plasma Sources Y. Yin, J. Messier, and J. Hopwood

    E-Print Network [OSTI]

    Miniaturization of Inductively Coupled Plasma Sources Y. Yin, J. Messier, and J. Hopwood Department associated with the miniaturization of planar inductively coupled plasmas (ICPs) are investigated" unless the plasma dimensions are determined more precisely by subtracting the sheath width from

  6. Method of processing materials using an inductively coupled plasma

    DOE Patents [OSTI]

    Hull, D.E.; Bieniewski, T.M.

    1987-04-13T23:59:59.000Z

    A method of processing materials. The invention enables ultrafine, ultrapure powders to be formed from solid ingots in a gas free environment. A plasma is formed directly from an ingot which insures purity. The vaporized material is expanded through a nozzle and the resultant powder settles on a cold surface. An inductively coupled plasma may also be used to process waste chemicals. Noxious chemicals are directed through a series of plasma tubes, breaking molecular bonds and resulting in relatively harmless atomic constituents. 3 figs.

  7. Inductively coupled plasma torch with laminar flow cooling

    DOE Patents [OSTI]

    Rayson, Gary D. (Las Cruces, NM); Shen, Yang (Las Cruces, NM)

    1991-04-30T23:59:59.000Z

    An improved inductively coupled gas plasma torch. The torch includes inner and outer quartz sleeves and tubular insert snugly fitted between the sleeves. The insert includes outwardly opening longitudinal channels. Gas flowing through the channels of the insert emerges in a laminar flow along the inside surface of the outer sleeve, in the zone of plasma heating. The laminar flow cools the outer sleeve and enables the torch to operate at lower electrical power and gas consumption levels additionally, the laminar flow reduces noise levels in spectroscopic measurements of the gaseous plasma.

  8. Electron energy distributions in a magnetized inductively coupled plasma

    SciTech Connect (OSTI)

    Song, Sang-Heon, E-mail: ssongs@umich.edu, E-mail: Sang-Heon.Song@us.tel.com [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, 2355 Bonisteel Boulevard, Ann Arbor, Michigan 48109-2104 (United States); Yang, Yang, E-mail: yang-yang@amat.com [Applied Materials Inc., 974 E. Arques Avenue, M/S 81312, Sunnyvale, California 94085 (United States); Chabert, Pascal, E-mail: pascal.chabert@lpp.polytechnique.fr [LPP, CNRS, Ecole Polytechnique, UPMC, Paris XI, 91128 Palaiseau (France); Kushner, Mark J., E-mail: mjkush@umich.edu [Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, Michigan 48109-2122 (United States)

    2014-09-15T23:59:59.000Z

    Optimizing and controlling electron energy distributions (EEDs) is a continuing goal in plasma materials processing as EEDs determine the rate coefficients for electron impact processes. There are many strategies to customize EEDs in low pressure inductively coupled plasmas (ICPs), for example, pulsing and choice of frequency, to produce the desired plasma properties. Recent experiments have shown that EEDs in low pressure ICPs can be manipulated through the use of static magnetic fields of sufficient magnitudes to magnetize the electrons and confine them to the electromagnetic skin depth. The EED is then a function of the local magnetic field as opposed to having non-local properties in the absence of the magnetic field. In this paper, EEDs in a magnetized inductively coupled plasma (mICP) sustained in Ar are discussed with results from a two-dimensional plasma hydrodynamics model. Results are compared with experimental measurements. We found that the character of the EED transitions from non-local to local with application of the static magnetic field. The reduction in cross-field mobility increases local electron heating in the skin depth and decreases the transport of these hot electrons to larger radii. The tail of the EED is therefore enhanced in the skin depth and depressed at large radii. Plasmas densities are non-monotonic with increasing pressure with the external magnetic field due to transitions between local and non-local kinetics.

  9. A Microfabricated Inductively-Coupled Plasma Generator Department of Electrical and Computer Engineering,

    E-Print Network [OSTI]

    of the supplied power. This mechanism of RF plasma generation is referred to as capacitive coupling. Electrodeless generation7 . The inductively-coupled plasma (ICP) is one type of electrodeless discharge that is now widelyA Microfabricated Inductively-Coupled Plasma Generator J. Hopwood Department of Electrical

  10. Fission Yield Measurements by Inductively Coupled Plasma Mass-Spectrometry

    SciTech Connect (OSTI)

    Irina Glagolenko; Bruce Hilton; Jeffrey Giglio; Daniel Cummings; Karl Grimm; Richard McKnight

    2009-11-01T23:59:59.000Z

    Correct prediction of the fission products inventory in irradiated nuclear fuels is essential for accurate estimation of fuel burnup, establishing proper requirements for spent fuel transportation and storage, materials accountability and nuclear forensics. Such prediction is impossible without accurate knowledge of neutron induced fission yields. Unfortunately, the accuracy of the fission yields reported in the ENDF/B-VII.0 library is not uniform across all of the data and much of the improvement is desired for certain isotopes and fission products. We discuss our measurements of cumulative fission yields in nuclear fuels irradiated in thermal and fast reactor spectra using Inductively Coupled Plasma Mass Spectrometry.

  11. Improvements in Inductively Coupled Plasma - Mass Spectrometry | The Ames

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh School footballHydrogenITLaboratory in Inductively Coupled Plasma

  12. Matrix effects in inductively coupled plasma mass spectrometry

    SciTech Connect (OSTI)

    Chen, Xiaoshan

    1995-07-07T23:59:59.000Z

    The inductively coupled plasma is an electrodeless discharge in a gas (usually Ar) at atmospheric pressure. Radio frequency energy generated by a RF power source is inductively coupled to the plasma gas through a water cooled load coil. In ICP-MS the {open_quotes}Fassel{close_quotes} TAX quartz torch commonly used in emission is mounted horizontally. The sample aerosol is introduced into the central flow, where the gas kinetic temperature is about 5000 K. The aerosol is vaporized, atomized, excited and ionized in the plasma, and the ions are subsequently extracted through two metal apertures (sampler and skimmer) into the mass spectrometer. In ICP-MS, the matrix effects, or non-spectroscopic interferences, can be defined as the type of interferences caused by dissolved concomitant salt ions in the solution. Matrix effects can be divided into two categories: (1) signal drift due to the deposition of solids on the sampling apertures; and/or (2) signal suppression or enhancement by the presence of the dissolved salts. The first category is now reasonably understood. The dissolved salts, especially refractory oxides, tend to deposit on the cool tip of the sampling cone. The clogging of the orifices reduces the ion flow into the ICP-MS, lowers the pressure in the first stage of ICP-MS, and enhances the level of metal oxide ions. Because the extent of the clogging increases with the time, the signal drifts down. Even at the very early stage of the development of ICP-MS, matrix effects had been observed. Houk et al. found out that the ICP-MS was not tolerant to solutions containing significant amounts of dissolved solids.

  13. Effect of bias application to plasma density in weakly magnetized inductively coupled plasma

    SciTech Connect (OSTI)

    Kim, Hyuk; Lee, Woohyun; Park, Wanjae; Whang, Ki-Woong [Plasma Laboratory, Department of Electrical Engineering and Computer Science, Seoul National University, 599 Kwanak-ro, Kwanak-gu, Seoul 151-742 (Korea, Republic of)

    2013-07-15T23:59:59.000Z

    Independent control of the ion flux and energy can be achieved in a dual frequency inductively coupled plasma (ICP) system. Typically, the plasma density is controlled by the high-frequency antenna radio-frequency (RF) power and the ion energy is controlled by the low-frequency bias RF power. Increasing the bias power has been known to cause a decrease in the plasma density in capacitively coupled discharge systems as well as in ICP systems. However, an applied axial magnetic field was found to sustain or increase the plasma density as bias power is increased. Measurements show higher electron temperatures but lower plasma densities are obtained in ordinary ICP systems than in magnetized ICP systems under the same neutral gas pressure and RF power levels. Explanations for the difference in the behavior of plasma density with increasing bias power are given in terms of the difference in the heating mechanism in ordinary unmagnetized and magnetized ICP systems.

  14. Effect of capacitive coupling in a miniature inductively coupled plasma source

    SciTech Connect (OSTI)

    Takao, Yoshinori; Eriguchi, Koji; Ono, Kouichi [Department of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)

    2012-11-01T23:59:59.000Z

    Two-dimensional axisymmetric particle-in-cell simulations with a Monte Carlo collision algorithm (PIC-MCC) have been conducted to investigate the effect of capacitive coupling in a miniature inductively coupled plasma source (mICP) by using two models: an inductive model and a hybrid model. The mICP is 3 mm in radius and 6 mm in height with a three-turn planar coil, where argon plasma is sustained. In the inductive model, the coil is assumed to be electrostatically shielded, and thus the discharge is purely inductive coupling. In the hybrid model, we assume that the different turns of the coil act like electrodes in capacitive discharge to include the effect of capacitive coupling. The voltage applied to these electrodes decreases linearly from the powered end of the coil towards the grounded end. The numerical analysis has been performed for rf frequencies in the range of 100-1000 MHz, and the power absorbed by the plasma in the range of 5-50 mW at a fixed pressure of 500 mTorr. The PIC-MCC results show that potential oscillations at the plasma-dielectric interface are not negligible, and thus the major component of the absorbed power is caused by the axial motion of electrons in the hybrid model, although almost all of the power absorption is due to the azimuthal motion of electrons in the inductive model. The effect of capacitive coupling is more significant at lower rf frequencies and at higher absorbed powers under the calculation conditions examined. Moreover, much less coil currents are required in the hybrid model.

  15. Plasma dynamics in a discharge produced by a pulsed dual frequency inductively coupled plasma source

    SciTech Connect (OSTI)

    Mishra, Anurag; Lee, Sehan [Department of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, Gyeonggi-do 440-746 (Korea, Republic of); Yeom, Geun Y., E-mail: gyyeom@skku.edu [Department of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, Gyeonggi-do 440-746, South Korea and SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon, Gyeonggi-do 440-746 (Korea, Republic of)

    2014-11-01T23:59:59.000Z

    Using a Langmuir probe, time resolved measurements of plasma parameters were carried out in a discharge produced by a pulsed dual frequency inductively coupled plasma source. The discharge was sustained in an argon gas environment at a pressure of 10 mTorr. The low frequency (P{sub 2} {sub MHz}) was pulsed at 1 kHz and a duty ratio of 50%, while high frequency (P{sub 13.56} {sub MHz}) was maintained in the CW mode. All measurements were carried out at the center of the discharge and 20?mm above the substrate. The results show that, at a particular condition (P{sub 2} {sub MHz}?=?200 W and P{sub 13.56} {sub MHz?}=?600 W), plasma density increases with time and stabilizes at up to ?200 ?s after the initiation of P{sub 2} {sub MHz} pulse at a plasma density of (2?×?10{sup 17} m{sup ?3}) for the remaining duration of pulse “on.” This stabilization time for plasma density increases with increasing P{sub 2} {sub MHz} and becomes ?300 ?s when P{sub 2} {sub MHz} is 600 W; however, the growth rate of plasma density is almost independent of P{sub 2} {sub MHz}. Interestingly, the plasma density sharply increases as the pulse is switched off and reaches a peak value in ?10 ?s, then decreases for the remaining pulse “off-time.” This phenomenon is thought to be due to the sheath modulation during the transition from “pulse on” to “pulse off” and partly due to RF noise during the transition period. The magnitude of peak plasma density in off time increases with increasing P{sub 2} {sub MHz}. The plasma potential and electron temperature decrease as the pulse develops and shows similar behavior to that of the plasma density when the pulse is switched off.

  16. In situ calibration of inductively coupled plasma-atomic emission and mass spectroscopy

    DOE Patents [OSTI]

    Braymen, Steven D. (Ames, IA)

    1996-06-11T23:59:59.000Z

    A method and apparatus for in situ addition calibration of an inductively coupled plasma atomic emission spectrometer or mass spectrometer using a precision gas metering valve to introduce a volatile calibration gas of an element of interest directly into an aerosol particle stream. The present situ calibration technique is suitable for various remote, on-site sampling systems such as laser ablation or nebulization.

  17. Comparison of plasma chemistries for inductively coupled plasma etching of InGaAlP alloys

    SciTech Connect (OSTI)

    Hong, J.; Lee, J.W.; Abernathy, C.R.; Lambers, E.S.; Pearton, S.J. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Shul, R.J. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Hobson, W.S. [Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey 07974 (United States)] [Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey 07974 (United States)

    1998-05-01T23:59:59.000Z

    Two plasma chemistries, i.e., CH{sub 4}/H{sub 2}/Ar and Cl{sub 2}/Ar, were compared for the etching of InGaP, AlInP, and AlGaP under inductively coupled plasma (ICP) conditions. While the etching with CH{sub 4}/H{sub 2}/Ar discharges appears to be ion driven, Cl{sub 2}/Ar discharges showed an additional strong chemical enhancement. The highest etch rate ({approximately}1 {mu}m/min) for InGaP was achieved at high ICP source power ({ge}750 W) with the Cl{sub 2}/Ar chemistry. Cl{sub 2}/Ar discharges provided very smooth surfaces in all three materials with root-mean-square roughness measured by atomic force microscopy around 2 nm. This result may be due to the efficient ion-assisted product desorption in this chemistry. The etched near-surface region of InGaP ({approximately}100 {Angstrom}) with Cl{sub 2}/Ar maintained almost the same stoichiometry as that of the unetched control. By contrast, the CH{sub 4}/H{sub 2}/Ar plasma chemistry produced somewhat rougher surfaces and depletion of phosphorous (P) from the surface of InGaP. {copyright} {ital 1998 American Vacuum Society.}

  18. Independent control of electron energy and density using a rotating magnetic field in inductively coupled plasmas

    SciTech Connect (OSTI)

    Kondo, Takahiro; Ohta, Masayuki; Ito, Tsuyohito; Okada, Shigefumi [Center for Atomic and Molecular Technologies, Graduate School of Engineering, Osaka University, Osaka 565-0871 (Japan)] [Center for Atomic and Molecular Technologies, Graduate School of Engineering, Osaka University, Osaka 565-0871 (Japan)

    2013-09-21T23:59:59.000Z

    Effects of a rotating magnetic field (RMF) on the electron energy distribution function (EEDF) and on the electron density are investigated with the aim of controlling the radical composition of inductively coupled plasmas. By adjusting the RMF frequency and generation power, the desired electron density and electron energy shift are obtained. Consequently, the amount and fraction of high-energy electrons, which are mostly responsible for direct dissociation processes of raw molecules, will be controlled externally. This controllability, with no electrode exposed to plasma, will enable us to control radical components and their flux during plasma processing.

  19. Plasma Diagnostics and Plasma-Surface Interactions in Inductively Coupled Plasmas

    E-Print Network [OSTI]

    Titus, Monica Joy

    2010-01-01T23:59:59.000Z

    intensities for pure Ar plasmas focus on the dominant 104.8emitted from pure A r plasmas focus on the intensities ofdissertation work focuses on plasma and wafer diagnostics as

  20. In situ calibration of inductively coupled plasma-atomic emission and mass spectroscopy

    DOE Patents [OSTI]

    Braymen, S.D.

    1996-06-11T23:59:59.000Z

    A method and apparatus are disclosed for in situ addition calibration of an inductively coupled plasma atomic emission spectrometer or mass spectrometer using a precision gas metering valve to introduce a volatile calibration gas of an element of interest directly into an aerosol particle stream. The present in situ calibration technique is suitable for various remote, on-site sampling systems such as laser ablation or nebulization. 5 figs.

  1. Plasma power measurement and hysteresis in the E-H transition of a rf inductively coupled plasma system

    SciTech Connect (OSTI)

    Daltrini, A. M.; Moshkalev, S. A. [Universidade Estadual de Campinas, Unicamp, Center for Semiconductor Components, P.O. Box 6061, Campinas SP 13083-870 (Brazil); Morgan, T. J. [Department of Physics, Wesleyan University, Middletown, Connecticut 06457 (United States); Piejak, R. B.; Graham, W. G. [Centre for Plasma Physics, Department of Physics and Astronomy, Queen's University Belfast BT 7 1NN, Northern Ireland (United Kingdom)

    2008-02-11T23:59:59.000Z

    An experimental investigation of the argon plasma behavior near the E-H transition in an inductively coupled Gaseous Electronics Conference reference cell is reported. Electron density and temperature, ion density, argon metastable density, and optical emission measurements have been made as function of input power and gas pressure. When plotted versus plasma power, applied power corrected for coil and hardware losses, no hysteresis is observed in the measured plasma parameter dependence at the E-H mode transition. This suggests that hysteresis in the E-H mode transition is due to ignoring inherent power loss, primarily in the matching system.

  2. Comparison of Solution-Based versus Laser Ablation Inductively Coupled Plasma Mass Spectrometry for Analysis of Larval Fish

    E-Print Network [OSTI]

    Comparison of Solution-Based versus Laser Ablation Inductively Coupled Plasma Mass Spectrometry otoliths of larvae. Herein, we evaluate the abilities of solution-based (SO) and laser ablation (LA

  3. Inductively coupled plasma mass spectrometry for stable isotope metabolic tracer studies of living systems

    SciTech Connect (OSTI)

    Luong, E.

    1999-05-10T23:59:59.000Z

    This dissertation focuses on the development of methods for stable isotope metabolic tracer studies in living systems using inductively coupled plasma single and dual quadrupole mass spectrometers. Sub-nanogram per gram levels of molybdenum (Mo) from human blood plasma are isolated by the use of anion exchange alumina microcolumns. Million-fold more concentrated spectral and matrix interferences such as sodium, chloride, sulfate, phosphate, etc. in the blood constituents are removed from the analyte. The recovery of Mo from the alumina column is 82 {+-} 5% (n = 5). Isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS) is utilized for the quantitative ultra-trace concentration determination of Mo in bovine and human blood samples. The average Mo concentration in reference bovine serum determined by this method is 10.2 {+-} 0.4 ng/g, while the certified value is 11.5 {+-} 1.1 ng/g (95% confidence interval). The Mo concentration of one pool of human blood plasma from two healthy male donors is 0.5 {+-} 0.1 ng/g. The inductively coupled plasma twin quadrupole mass spectrometer (ICP-TQMS) is used to measure the carbon isotope ratio from non-volatile organic compounds and bio-organic molecules to assess the ability as an alternative analytical method to gas chromatography combustion isotope ratio mass spectrometry (GC-combustion-IRMS). Trytophan, myoglobin, and {beta}-cyclodextrin are chosen for the study, initial observation of spectral interference of {sup 13}C{sup +} with {sup 12}C{sup 1}H{sup +} comes from the incomplete dissociation of myoglobin and/or {beta}-cyclodextrin.

  4. Reduced electron temperature in a magnetized inductively-coupled plasma with internal coil

    SciTech Connect (OSTI)

    Arancibia Monreal, J.; Chabert, P. [LPP, CNRS, Ecole Polytechnique, UPMC, Paris XI, 91128 Palaiseau (France)] [LPP, CNRS, Ecole Polytechnique, UPMC, Paris XI, 91128 Palaiseau (France); Godyak, V. [RF Plasma Consulting, Brookline, Massachusetts 02446 (United States) [RF Plasma Consulting, Brookline, Massachusetts 02446 (United States); Michigan Institute for Plasma Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2013-10-15T23:59:59.000Z

    The effect of magnetic filtering on the electron energy distribution function is studied in an inductive discharge with internal coil coupling. The coil is placed inside the plasma and driven by a low-frequency power supply (5.8 MHz) which leads to a very high power transfer efficiency. A permanent dipole magnet may be placed inside the internal coil to produce a static magnetic field around 100 Gauss. The coil and the matching system are designed to minimize the capacitive coupling to the plasma. Capacitive coupling is quantified by measuring the radiofrequency (rf) plasma potential with a capacitive probe. Without the permanent magnet, the rf plasma potential is significantly smaller than the electron temperature. When the magnet is present, the rf plasma potential increases. The electron energy distribution function is measured as a function of space with and without the permanent magnet. When the magnet is present, electrons are cooled down to low temperature in the downstream region. This region of low electron temperature may be useful for plasma processing applications, as well as for efficient negative ion production.

  5. Double layer formation in the expanding region of an inductively coupled electronegative plasma

    E-Print Network [OSTI]

    Plihon, N; Chabert, P

    2015-01-01T23:59:59.000Z

    Double-layers (DLs) were observed in the expanding region of an inductively coupled plasma with $\\text{Ar}/\\text{SF}\\_6$ gas mixtures. No DL was observed in pure argon or $\\text{SF}\\_6$ fractions below few percent. They exist over a wide range of power and pressure although they are only stable for a small window of electronegativity (typically between 8\\% and 13\\% of $\\text{SF}\\_6$ at 1mTorr), becoming unstable at higher electronegativity. They seem to be formed at the boundary between the source tube and the diffusion chamber and act as an internal boundary (the amplitude being roughly 1.5$\\frac{kT\\_e}{e}$)between a high electron density, high electron temperature, low electronegativity plasma upstream (in the source), and a low electron density, low electron temperature, high electronegativity plasma downstream.

  6. On the possibility of the multiple inductively coupled plasma and helicon plasma sources for large-area processes

    SciTech Connect (OSTI)

    Lee, Jin-Won; Lee, Yun-Seong, E-mail: leeeeys@kaist.ac.kr; Chang, Hong-Young [Low-temperature Plasma Laboratory, Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); An, Sang-Hyuk [Agency of Defense Development, Yuseong-gu, Daejeon 305-151 (Korea, Republic of)

    2014-08-15T23:59:59.000Z

    In this study, we attempted to determine the possibility of multiple inductively coupled plasma (ICP) and helicon plasma sources for large-area processes. Experiments were performed with the one and two coils to measure plasma and electrical parameters, and a circuit simulation was performed to measure the current at each coil in the 2-coil experiment. Based on the result, we could determine the possibility of multiple ICP sources due to a direct change of impedance due to current and saturation of impedance due to the skin-depth effect. However, a helicon plasma source is difficult to adapt to the multiple sources due to the consistent change of real impedance due to mode transition and the low uniformity of the B-field confinement. As a result, it is expected that ICP can be adapted to multiple sources for large-area processes.

  7. UV and IR laser ablation for inductively coupled plasma mass spectrometry

    SciTech Connect (OSTI)

    Smith, M.R.; Koppenaal, D.W.; Farmer, O.T.

    1993-06-01T23:59:59.000Z

    Laser ablation particle plume compositions are characterized using inductively coupled plasma mass spectrometry (ICP/MS). This study evaluates the mass response characteristics peculiar to ICP/MS detection as a function of laser fluence and frequency. Evaluation of the ICP/MS mass response allows deductions to be made concerning how representative the laser ablation produced particle plume composition is relative to the targeted sample. Using a black glass standard, elemental fractionation was observed, primarily for alkalis and other volatile elements. The extent of elemental fractionation between the target sample and the sampled plume varied significantly as a function of laser fluences and IR and UV laser frequency.

  8. On anomalous temporal evolution of gas pressure in inductively coupled plasma

    SciTech Connect (OSTI)

    Seo, B. H.; Chang, H. Y. [Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of)] [Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); You, S. J.; Kim, J. H.; Seong, D. J. [Center for Vacuum Technology, Korea Research Institute of Standards and Science, Daejeon 305-306 (Korea, Republic of)] [Center for Vacuum Technology, Korea Research Institute of Standards and Science, Daejeon 305-306 (Korea, Republic of)

    2013-04-01T23:59:59.000Z

    The temporal measurement of gas pressure in inductive coupled plasma revealed that there is an interesting anomalous evolution of gas pressure in the early stage of plasma ignition and extinction: a sudden gas pressure change and its relaxation of which time scales are about a few seconds and a few tens of second, respectively, were observed after plasma ignition and extinction. This phenomenon can be understood as a combined result between the neutral heating effect induced by plasma and the pressure relaxation effect for new gas temperature. The temporal measurement of gas temperature by laser Rayleigh scattering and the time dependant calculations for the neutral heating and pressure relaxation are in good agreement with our experimental results. This result and physics behind are expected to provide a new operational perspective of the recent plasma processes of which time is very short, such as a plasma enhanced atomic layer deposition/etching, a soft etch for disposal of residual by-products on wafer, and light oxidation process in semiconductor manufacturing.

  9. Induction plasma tube

    DOE Patents [OSTI]

    Hull, D.E.

    1982-07-02T23:59:59.000Z

    An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.

  10. Induction plasma tube

    DOE Patents [OSTI]

    Hull, Donald E. (Los Alamos, NM)

    1984-01-01T23:59:59.000Z

    An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.

  11. E?H mode transition density and power in two types of inductively coupled plasma configuration

    SciTech Connect (OSTI)

    Wang, Jian; Du, Yin-chang; Zhang, Xiao; Zheng, Zhe; Liu, Yu; Xu, Liang; Wang, Pi; Cao, Jin-xiang, E-mail: jxcao@ustc.edu.cn [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2014-07-15T23:59:59.000Z

    E???H transition power and density were investigated at various argon pressures in inductively coupled plasma (ICP) in a cylindrical interlaid chamber. The transition power versus the pressure shows a minimum transition power at 4?Pa (?/?=1) for argon. Then the transition density hardly changes at low pressures (?/??1), but it increases clearly when argon pressure exceeds an appropriate value. In addition, both the transition power and transition density are lower in the re-entrant configuration of ICP compared with that in the cylindrical configuration of ICP. The result may be caused from the decrease of stochastic heating in the re-entrant configuration of ICP. This work is useful to understand E???H mode transition and control the transition points in real plasma processes.

  12. Low-frequency, self-sustained oscillations in inductively coupled plasmas used for optical pumping

    SciTech Connect (OSTI)

    Coffer, J.; Encalada, N.; Huang, M.; Camparo, J. [Physical Sciences Laboratories, The Aerospace Corporation 2310, E. El Segundo Blvd., El Segundo, California 90245 (United States)

    2014-10-28T23:59:59.000Z

    We have investigated very low frequency, on the order of one hertz, self-pulsing in alkali-metal inductively-coupled plasmas (i.e., rf-discharge lamps). This self-pulsing has the potential to significantly vary signal-to-noise ratios and (via the ac-Stark shift) resonant frequencies in optically pumped atomic clocks and magnetometers (e.g., the atomic clocks now flying on GPS and Galileo global navigation system satellites). The phenomenon arises from a nonlinear interaction between the atomic physics of radiation trapping and the plasma's electrical nature. To explain the effect, we have developed an evaporation/condensation theory (EC theory) of the self-pulsing phenomenon.

  13. Methods for detecting and correcting inaccurate results in inductively coupled plasma-atomic emission spectrometry

    DOE Patents [OSTI]

    Chan, George C. Y. (Bloomington, IN); Hieftje, Gary M. (Bloomington, IN)

    2010-08-03T23:59:59.000Z

    A method for detecting and correcting inaccurate results in inductively coupled plasma-atomic emission spectrometry (ICP-AES). ICP-AES analysis is performed across a plurality of selected locations in the plasma on an unknown sample, collecting the light intensity at one or more selected wavelengths of one or more sought-for analytes, creating a first dataset. The first dataset is then calibrated with a calibration dataset creating a calibrated first dataset curve. If the calibrated first dataset curve has a variability along the location within the plasma for a selected wavelength, errors are present. Plasma-related errors are then corrected by diluting the unknown sample and performing the same ICP-AES analysis on the diluted unknown sample creating a calibrated second dataset curve (accounting for the dilution) for the one or more sought-for analytes. The cross-over point of the calibrated dataset curves yields the corrected value (free from plasma related errors) for each sought-for analyte.

  14. Comparison of various interpretation methods of the electric probe measurements in inductively coupled Ar and O{sub 2} plasmas

    SciTech Connect (OSTI)

    Woo Seo, Min; Keun Bae, Min; Chung, T. H., E-mail: thchung@dau.ac.kr [Department of Physics, Dong-A University, Busan 604-714 (Korea, Republic of)

    2014-02-15T23:59:59.000Z

    In low-pressure inductively coupled argon and oxygen discharges, the plasma density and electron temperature and the electron energy distribution function (EEDF) were obtained by using a cylindrical electric probe. The plasma densities were determined by various methods to interpret the probe current-voltage characteristic curve: the EEDF integration, the electron saturation current, the ion current at the floating potential, and the orbital-motion-limited (OML) ion current. Quite a good agreement exists between the plasma densities determined by various classical methods. Although the probe technique has some limitation in electronegative plasmas, the plasma densities determined from OML theory compare well with those measured by the ion saturation current at the floating potential in the oxygen discharges. In addition, the EEDFs of inductively coupled Ar and oxygen plasmas are observed to be nearly Maxwellian at the pressure range of 1-40 mTorr.

  15. High Resolution Studies of the Origins of Polyatomic Ions in Inductively Coupled Plasma-Mass Spectrometry

    SciTech Connect (OSTI)

    Jill Wisnewski Ferguson

    2006-08-09T23:59:59.000Z

    The inductively coupled plasma (ICP) is an atmospheric pressure ionization source. Traditionally, the plasma is sampled via a sampler cone. A supersonic jet develops behind the sampler, and this region is pumped down to a pressure of approximately one Torr. A skimmer cone is located inside this zone of silence to transmit ions into the mass spectrometer. The position of the sampler and skimmer cones relative to the initial radiation and normal analytical zones of the plasma is key to optimizing the useful analytical signal [1]. The ICP both atomizes and ionizes the sample. Polyatomic ions form through ion-molecule interactions either in the ICP or during ion extraction [l]. Common polyatomic ions that inhibit analysis include metal oxides (MO{sup +}), adducts with argon, the gas most commonly used to make up the plasma, and hydride species. While high resolution devices can separate many analytes from common interferences, this is done at great cost in ion transmission efficiency--a loss of 99% when using high versus low resolution on the same instrument [2]. Simple quadrupole devices, which make up the bulk of ICP-MS instruments in existence, do not present this option. Therefore, if the source of polyatomic interferences can be determined and then manipulated, this could potentially improve the figures of merit on all ICP-MS devices, not just the high resolution devices often utilized to study polyatomic interferences.

  16. Mode transition in CF{sub 4} + Ar inductively coupled plasma

    SciTech Connect (OSTI)

    Liu, Wei; Gao, Fei; Zhao, Shu-Xia; Li, Xue-Chun; Wang, You-Nian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2013-12-15T23:59:59.000Z

    The E to H mode transitions are studied by a hairpin probe and optical emission spectroscopy in inductively coupled CF{sub 4} + Ar plasmas. Electron density, optical emission intensity of Ar, and the voltage and current are measured during the E to H mode transitions. It is found that the electron density and plasma emission intensity increase continuously at low pressure during the E to H mode transition, while they jump up discontinuously at high pressure. Meanwhile, the transition threshold power and ?P (the power interval between E and H mode) increase by increasing the pressure. When the ratio of CF{sub 4} increases, the E to H mode transition happens at higher applied power, and meanwhile, the ?P also significantly increases. Besides, the effects of CF{sub 4} gas ratio on the plasma properties and the circuit electrical properties in both pure E and H modes were also investigated. The electron density and plasma emission intensity both decrease upon increasing the ratio of CF{sub 4} at the two modes, due to the stronger electrons loss scheme. The applied voltages at E and H modes both increase as increasing the CF{sub 4} gas ratio, however the applied current at two modes behave just oppositely with the gas ratio.

  17. Anisotropic Ta{sub 2}O{sub 5} waveguide etching using inductively coupled plasma etching

    SciTech Connect (OSTI)

    Muttalib, Muhammad Firdaus A., E-mail: mfam1g08@ecs.soton.ac.uk; Chen, Ruiqi Y.; Pearce, Stuart J.; Charlton, Martin D. B. [Nano Research Group, Electronics and Computer Science, Faculty of Physical and Applied Sciences, University of Southampton, Southampton SO17 1BJ (United Kingdom)

    2014-07-01T23:59:59.000Z

    Smooth and vertical sidewall profiles are required to create low loss rib and ridge waveguides for integrated optical device and solid state laser applications. In this work, inductively coupled plasma (ICP) etching processes are developed to produce high quality low loss tantalum pentoxide (Ta{sub 2}O{sub 5}) waveguides. A mixture of C{sub 4}F{sub 8} and O{sub 2} gas are used in combination with chromium (Cr) hard mask for this purpose. In this paper, the authors make a detailed investigation of the etch process parameter window. Effects of process parameters such as ICP power, platen power, gas flow, and chamber pressure on etch rate and sidewall slope angle are investigated. Chamber pressure is found to be a particularly important factor, which can be used to tune the sidewall slope angle and so prevent undercut.

  18. Inductively Coupled Plasma: Fundamental Particle Investigations with Laser Ablation and Applications in Magnetic Sector Mass Spectrometry

    SciTech Connect (OSTI)

    Nathan Joe Saetveit

    2008-08-18T23:59:59.000Z

    Particle size effects and elemental fractionation in laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) are investigated with nanosecond and femtosecond laser ablation, differential mobility analysis, and magnetic sector ICP-MS. Laser pulse width was found to have a significant influence on the LA particle size distribution and the elemental composition of the aerosol and thus fractionation. Emission from individual particles from solution nebulization, glass, and a pressed powder pellet are observed with high speed digital photography. The presence of intact particles in an ICP is shown to be a likely source of fractionation. A technique for the online detection of stimulated elemental release from neural tissue using magnetic sector ICP-MS is described. Detection limits of 1 {micro}g L{sup -1} or better were found for P, Mn, Fe, Cu, and Zn in a 60 {micro}L injection in a physiological saline matrix.

  19. Atlas of Atomic Spectral Lines of Neptunium Emitted by Inductively Coupled Plasma

    SciTech Connect (OSTI)

    DeKalb, E.L. and Edelson, M. C.

    1987-08-01T23:59:59.000Z

    Optical emission spectra from high-purity Np-237 were generated with a glovebox-enclosed inductively coupled plasma (ICP) source. Spectra covering the 230-700 nm wavelength range are presented along with general commentary on the methodology used in collecting the data. The Ames Laboratory Nuclear Safeguards and Security Program has been charged with the task of developing optical spectroscopic methods to analyze the composition of spent nuclear fuels. Such materials are highly radioactive even after prolonged 'cooling' and are chemically complex. Neptunium (Np) is a highly toxic by-product of nuclear power generation and is found, in low abundance, in spent nuclear fuels. This atlas of the optical emission spectrum of Np, as produced by an inductively coupled plasma (ICP) spectroscopic source, is part of a general survey of the ICP emission spectra of the actinide elements. The ICP emission spectrum of the actinides originates almost exclusively from the electronic relaxation of excited, singly ionized species. Spectral data on the Np ion emission spectrum (i.e., the Np II spectrum) have been reported by Tomkins and Fred [1] and Haaland [2]. Tomkins and Fred excited the Np II spectrum with a Cu spark discharge and identified 114 Np lines in the 265.5 - 436.3 nm spectral range. Haaland, who corrected some spectral line misidentifications in the work of Tomkins and Fred, utilized an enclosed Au spark discharge to excite the Np II spectrum and reported 203 Np lines within the 265.4 - 461.0 nm wavelength range.

  20. Inductively Coupled Plasma and Electron Cyclotron Resonance Plasma Etching of InGaAlP Compound Semiconductor System

    SciTech Connect (OSTI)

    Abernathy, C.R.; Hobson, W.S.; Hong, J.; Lambers, E.S.; Pearton, S.J.; Shul, R.J.

    1998-11-04T23:59:59.000Z

    Current and future generations of sophisticated compound semiconductor devices require the ability for submicron scale patterning. The situation is being complicated since some of the new devices are based on a wider diversity of materials to be etched. Conventional IUE (Reactive Ion Etching) has been prevalent across the industry so far, but has limitations for materials with high bond strengths or multiple elements. IrI this paper, we suggest high density plasmas such as ECR (Electron Cyclotron Resonance) and ICP (Inductively Coupled Plasma), for the etching of ternary compound semiconductors (InGaP, AIInP, AlGaP) which are employed for electronic devices like heterojunction bipolar transistors (HBTs) or high electron mobility transistors (HEMTs), and photonic devices such as light-emitting diodes (LEDs) and lasers. High density plasma sources, opeiating at lower pressure, are expected to meet target goals determined in terms of etch rate, surface morphology, surface stoichiometry, selectivity, etc. The etching mechanisms, which are described in this paper, can also be applied to other III-V (GaAs-based, InP-based) as well as III-Nitride since the InGaAIP system shares many of the same properties.

  1. Fundamental and methodological investigations for the improvement of elemental analysis by inductively coupled plasma mass soectrometry

    SciTech Connect (OSTI)

    Ebert, Christopher Hysjulien [Ames Laboratory

    2012-07-27T23:59:59.000Z

    This dissertation describes a variety of studies meant to improve the analytical performance of inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation (LA) ICP-MS. The emission behavior of individual droplets and LA generated particles in an ICP is studied using a high-speed, high frame rate digital camera. Phenomena are observed during the ablation of silicate glass that would cause elemental fractionation during analysis by ICP-MS. Preliminary work for ICP torch developments specifically tailored for the improvement of LA sample introduction are presented. An abnormal scarcity of metal-argon polyatomic ions (MAr{sup +}) is observed during ICP-MS analysis. Evidence shows that MAr{sup +} ions are dissociated by collisions with background gas in a shockwave near the tip of the skimmer cone. Method development towards the improvement of LA-ICP-MS for environmental monitoring is described. A method is developed to trap small particles in a collodion matrix and analyze each particle individually by LA-ICP-MS.

  2. Arsenic speciation in soil using high performance liquid chromatography/inductively coupled plasma/mass spectrometry

    SciTech Connect (OSTI)

    Bass, D.A.; Yaeger, J.S.; Parish, K.J.; Crain, J.S.; Kiely, J.T.; Gowdy, M.J. [Argonne National Lab., IL (United States); Mohrman, G.B.; Besmer, M.G. [Rocky Mountain Arsenal, Commerce City, CO (United States)

    1996-08-01T23:59:59.000Z

    A method has been developed to identify and quantify As(III), As(V), and organoarsenic compounds in soil samples from the Rocky Mountain Arsenal (RMA) by high performance liquid chromatography/inductively coupled plasma/mass spectrometry (HPLC/ICP/MS). The soils were extracted using tetrabutylammonium hydroxide (TBAH) and sonication. The percentages of As(III), As(V), and organoarsenic species extracted from soil samples were 30, 50, and 100 respectively. The arsenic species were not altered during the extraction process. They were separated by reversed-phase, ion-pairing, HPLC using a microbore Inertsil-ODS{trademark} column. The HPLC column effluent was introduced into an ICP/MS system using a direct injection nebulizer (DIN). Detection limits of less than 1 pg were readily obtained for each arsenic species. Internal standards are recommended to increase accuracy and precision. Soil samples spiked with arsenic oxide, sodium arsenate, dimethylarsinic acid (DMAA), and chlorovinyl arsenious acid (CVAA) were extracted, identified and quantified with the HPLC/ICP/MS system. The soil samples were analyzed in support of the analytical needs of a thermal desorption treatability study being conducted at the RMA.

  3. Investigation of magnetic-pole-enhanced inductively coupled nitrogen-argon plasmas

    SciTech Connect (OSTI)

    Jan, F.; Zakaullah, M. [Department of Physics, Quaid-i-Azam University Islamabad, Islamabad 45320 (Pakistan); Khan, A. W.; Saeed, A. [National Centre for Physics, Quaid-i-Azam University Campus Islamabad, Islamabad 45320 (Pakistan)

    2012-09-15T23:59:59.000Z

    This article presented the features of the mixed mode and H mode in magnetic pole enhanced, inductively coupled Ar-N{sub 2} plasmas using RF-compensated Langmuir probe measurements. To fully characterize plasma parameters and electron energy probability functions (EEPFs), the gas pressure and argon content were varied. It was observed that with increasing the nitrogen content and gas pressure, the critical RF power to sustain H mode increases; this increase was more prominent for pure nitrogen discharge at higher pressure. The electron number density (n{sub e}) shows increasing trend with increasing RF power, while at higher gas pressures, the electron number density decreases at fixed RF power. Mostly, the EEPFs show a Maxwellian distribution even at low RF power (for higher argon content in the discharge) and at moderate RF power (for higher or pure nitrogen content in the discharge) for pressures of 15-60 mTorr. With increasing the nitrogen content in the mixture, the low energy part of the EEPF is more Druyvesteyn with a distorted high energy tail at low RF power. At fixed RF power, the slope of EEPF changes sharply with increasing pressure. It was observed that in hybrid mode, the EEPF at higher gas pressure (75 mTorr) in a pure nitrogen discharge shows a flat hole near the average electron energy of 3 eV and changes to Maxwellian distribution in H mode. The skin depth versus RF power shows that the skin depth is smaller than the critical dimension of the chamber, regardless of the gas type and the gas pressure.

  4. Radical kinetics in an inductively-coupled plasma in CF4

    SciTech Connect (OSTI)

    Booth, J.P.; Abada, H.; Chabert, P. [Laboratoire de Physique et Technologie des Plasmas, Ecole Polytechnique, 91128 Palaiseau (France); Graves, D.B. [Dept. of Chemical Engineering, University of California, Berkeley, California 94720 (United States)

    2004-12-01T23:59:59.000Z

    Radiofrequency discharges in low pressure fluorocarbon gases are used for anisotropic and selective etching of dielectric materials (SiO2 and derivatives), a key step in the manufacture of integrated circuits. Plasmas in these gases are capable not only of etching, but also of depositing fluorocarbon films, depending on a number of factors including the ion bombardment energy, the gas composition and the surface temperature: this behavior is indeed responsible for etch selectivity between materials and plays a role in achieving the desired etched feature profiles. Free radical species, such as CFx and fluorine atoms, play important but complex roles in these processes. We have used laser-induced fluorescence (LIF), with time and space resolution in pulsed plasmas, to elucidate the kinetics of CF and CF2 radicals, elucidating their creation, destruction and transport mechanisms within the reactor. Whereas more complex gas mixtures are used in industrial processes, study of the relatively simple system of a pure CF4 plasma is more appropriate for the study of mechanisms. Previously the technique was applied to the study of single-frequency capacitively-coupled 'reactive ion etching' reactors, where the substrate (placed on the powered electrode) is always bombarded with high-energy CF{sub x}{sup +} ions. In this case it was found that the major source of CFx free radicals was neutralization, dissociation and backscattering of these incident ions, rather than direct dissociation of the feedstock gas. Subsequently, an inductively-coupled plasma (ICP) in pure CF4 was studied. This system has a higher plasma density, leading to higher gas dissociation, whereas the energy of ions striking the reactor surfaces is much lower (in the absence of additional RF biasing). The LIF technique also allows the gas temperature to be measured with good spatial and temporal resolution. This showed large gas temperature gradients within the ICP reactor, which must be taken into account in reactive species transport. In the ICP reactor we saw significant production of CF and CF2 radicals at the reactor top and bottom surfaces, at rates that cannot be explained by the neutralization of incident CF{sub x}{sup +} ions. These two species are also lost at very high rates in the gas phase. We postulate that these two phenomena are caused by electron-impact excitation of these radicals into low-lying metastable levels. The metastable molecules produced (that are invisible to LIF) diffuse to the reactor walls where they are quenched back to their ground state. In the afterglow the gas cools rapidly and contracts, causing gas convection. Whereas the density of the more reactive species decays monotonically in the afterglow, the density of CF2 initially increases. This is partly due to the gas contraction, bringing back CF2 (which is a relatively stable species) from the outer regions of the reactor, and partly due to chemical reactions producing CF2, as it is more thermodynamically stable than the other radical species such as CF and CF3.

  5. A study on the maximum power transfer condition in an inductively coupled plasma using transformer circuit model

    SciTech Connect (OSTI)

    Kim, Young-Do; Lee, Hyo-Chang; Chung, Chin-Wook [Department of Electrical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of)] [Department of Electrical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of)

    2013-09-15T23:59:59.000Z

    Correlations between the external discharge parameters (the driving frequency ? and the chamber dimension R) and plasma characteristics (the skin depth ? and the electron-neutral collision frequency ?{sub m}) are studied using the transformer circuit model [R. B. Piejak et al., Plasma Sources Sci. Technol. 1, 179 (1992)] when the absorbed power is maximized in an inductively coupled plasma. From the analysis of the transformer circuit model, the maximum power transfer conditions, which depend on the external discharge parameters and the internal plasma characteristics, were obtained. It was found that a maximum power transfer occurs when ??0.38R for the discharge condition at which ?{sub m}/??1, while it occurs when ???(2)?(?/?{sub m})R for the discharge condition at which ?{sub m}/??1. The results of this circuit analysis are consistent with the stable last inductive mode region of an inductive-to-capacitive mode transition [Lee and Chung, Phys. Plasmas 13, 063510 (2006)], which was theoretically derived from Maxwell's equations. Our results were also in agreement with the experimental results. From this work, we demonstrate that a simple circuit analysis can be applied to explain complex physical phenomena to a certain extent.

  6. Fundamental studies of the plasma extraction and ion beam formation processes in inductively coupled plasma mass spectrometry

    SciTech Connect (OSTI)

    Niu, Hongsen

    1995-02-10T23:59:59.000Z

    The fundamental and practical aspects are described for extracting ions from atmospheric pressure plasma sources into an analytical mass spectrometer. Methodologies and basic concepts of inductively coupled plasma mass spectrometry (ICP-MS) are emphasized in the discussion, including ion source, sampling interface, supersonic expansion, slumming process, ion optics and beam focusing, and vacuum considerations. Some new developments and innovative designs are introduced. The plasma extraction process in ICP-MS was investigated by Langmuir measurements in the region between the skimmer and first ion lens. Electron temperature (T{sub e}) is in the range 2000--11000 K and changes with probe position inside an aerosol gas flow. Electron density (n{sub e}) is in the range 10{sup 8}--10{sup 10} {sup {minus}cm }at the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} near the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} downstream further behind the skimmer. Electron density in the beam leaving the skimmer also depends on water loading and on the presence and mass of matrix elements. Axially resolved distributions of electron number-density and electron temperature were obtained to characterize the ion beam at a variety of plasma operating conditions. The electron density dropped by a factor of 101 along the centerline between the sampler and skimmer cones in the first stage and continued to drop by factors of 10{sup 4}--10{sup 5} downstream of skimmer to the entrance of ion lens. The electron density in the beam expansion behind sampler cone exhibited a 1/z{sup 2} intensity fall-off (z is the axial position). An second beam expansion originated from the skimmer entrance, and the beam flow underwent with another 1/z{sup 2} fall-off behind the skimmer. Skimmer interactions play an important role in plasma extraction in the ICP-MS instrument.

  7. Multi-Collector Inductively Coupled Plasma Mass Spectrometer – Operational Performance Report

    SciTech Connect (OSTI)

    Matthew Watrous; Anthony Appelhans; Robert Hague; John Olson; Tracy Houghton

    2013-06-01T23:59:59.000Z

    The INL made an assessment of the commercially available inductively coupled plasma mass spectrometers (ICPMS) for actinide analysis; emphasizing low detection limits for plutonium. INL scientists subsequently determined if plutonium was present on a swipe, at a 10 million atom decision level. This report describes the evaluation of ICPMS instruments and the operational testing of a new process for the dissolution, separation and analysis via ICPMS of swipes for plutonium and uranium. The swipe dissolution, plutonium and uranium isolation, separation and purification are wet chemistry methods following established procedures. The ICPMS is a commercially available multi-collector magnetic sector mass spectrometer that utilizes five ion counting detectors operating simultaneously. The instrument includes a sample introduction system allowing for sample volumes of < 1 mL to be reproducibly injected into the instrument with minimal waste of the sample solution, while maximizing the useable signal. The performance of the instrument was measured using SRM 996 (244Pu spike) at concentrations of 12 parts per quadrillion (ppq, fg/mL) and with SRM 4350B Columbia River Sediment samples spiked onto swipes at the 10 million atom level. The measured limit of detection (LOD, defined as 3s) for 239Pu is 310,000 atoms based upon the instrument blank data. The limit of quantification (LOQ defined as 10 s) for 239Pu is 105,000 atoms. The measured limit of detection for 239Pu from the SRM 4350B spiked onto a swipe was 2.7 million atoms with the limit of quantification being 9.0 million atoms.

  8. The PERC{trademark} process: Existing and potential applications for induction coupled plasma technology in hazardous and radioactive waste treatment

    SciTech Connect (OSTI)

    Blutke, A.S.; Vavruska, J.S.; Serino, J.F. [Plasma Technology, Inc., Santa Fe, NM (United States)

    1996-12-31T23:59:59.000Z

    Plasma Technology, Inc. (PTI), a Santa Fe, New Mexico corporation has developed the Plasma Energy Recycle and Conversion (PERC){trademark} treatment process as a safe and environmentally clean alternative to conventional thermal destruction technologies. The PERC{trademark} treatment process uses as its heat source an advanced Induction Coupled Plasma (ICP) torch connected to a reaction chamber system with an additional emission control system. For example, organic-based gas, liquid, slurry, and/or solid waste streams can be converted into usable or even salable products while residual emissions are reduced to an absolute minimum. In applications for treatment of hazardous and radioactive waste streams, the PERC system could be used for destruction of the hazardous organic constituents and/or significant waste volume reduction while capturing the radioactive fraction in a non-leachable form. Like Direct Current (DC) and Alternating Current (AC) arc plasma systems, ICP torches offer sufficient energy to decompose, melt and/or vitrify any waste stream. The decision for an arc plasma or an IC plasma system has to be made on a case by case evaluation and is highly dependent on the specific waste stream`s form and composition. Induction coupled plasma technology offers one simple, but significant difference compared to DC or AC arc plasma systems: the ICP torch is electrodeless. To date, enormous research effort has been spent to improve the lifetime of electrodes and the effectiveness of related cooling systems. Arc plasma systems are established in research laboratories worldwide and are approaching a broad use in commercial applications. ICP technology has been improved relatively recently, but nowadays offers complete new and beneficial approaches in the field of waste conversion and treatment.

  9. Investigations into the origins of polyatomic ions in inductively coupled plasma-mass spectrometry

    SciTech Connect (OSTI)

    McIntyre, Sally M.

    2010-05-16T23:59:59.000Z

    An inductively coupled plasma-mass spectrometer (ICP-MS) is an elemental analytical instrument capable of determining nearly all elements in the periodic table at limits of detection in the parts per quadrillion and with a linear analytical range over 8-10 orders of magnitude. Three concentric quartz tubes make up the plasma torch. Argon gas is spiraled through the outer tube and generates the plasma powered by a looped load coil operating at 27.1 or 40.6 MHz. The argon flow of the middle channel is used to keep the plasma above the innermost tube through which solid or aqueous sample is carried in a third argon stream. A sample is progressively desolvated, atomized and ionized. The torch is operated at atmospheric pressure. To reach the reduced pressures of mass spectrometers, ions are extracted through a series of two, approximately one millimeter wide, circular apertures set in water cooled metal cones. The space between the cones is evacuated to approximately one torr. The space behind the second cone is pumped down to, or near to, the pressure needed for the mass spectrometer (MS). The first cone, called the sampler, is placed directly in the plasma plume and its position is adjusted to the point where atomic ions are most abundant. The hot plasma gas expands through the sampler orifice and in this expansion is placed the second cone, called the skimmer. After the skimmer traditional MS designs are employed, i.e. quadrupoles, magnetic sectors, time-of-flight. ICP-MS is the leading trace element analysis technique. One of its weaknesses are polyatomic ions. This dissertation has added to the fundamental understanding of some of these polyatomic ions, their origins and behavior. Although mainly continuing the work of others, certain novel approaches have been introduced here. Chapter 2 includes the first reported efforts to include high temperature corrections to the partition functions of the polyatomic ions in ICP-MS. This and other objections to preceeding papers in this area were addressed. Errors in the measured T{sub gas} values were found for given errors in the experimental and spectroscopic values. The ionization energy of the neutral polyatomic ion was included in calculations to prove the validity of ignoring more complicated equilibria. Work was begun on the question of agreement between kinetics of the plasma and interface and the increase and depletion seen in certain polyatomic ions. This dissertation was also the first to report day to day ranges for T{sub gas} values and to use a statistical test to compare different operating conditions. This will help guide comparisons of previous and future work. Chapter 4 was the first attempt to include the excited electronic state 2 in the partition function of ArO{sup +} as well as the first to address the different dissociation products of the ground and first electronic levels of ArO{sup +}. Chapter 5 reports an interesting source of memory in ICP-MS that could affect mathematical corrections for polyatomic ions. For future work on these topics I suggest the following experiments and investigations. Clearly not an extensive list, they are instead the first topics curiosity brings to mind. (1) Measurement of T{sub gas} values when using the flow injection technique of Appendix B. It was believed that there was a fundamental difference in the plasma when the auto-sampler was used versus a continuous injection. Is this reflected in T{sub gas} values? (2) The work of Chapter 3 can be expanded and supplemented with more trials, new cone materials (i.e. copper, stainless steel) and more cone geometries. Some of this equipment is already present in the laboratory, others could be purchased or made. (3) T{sub gas} values from Chapter 3 could be correlated with instrument pressures during the experiment. Pressures after the skimmer cone were recorded for many days but have yet to be collated with the measured T{sub gas} values. (4) The work in Chapter 5 could be expanded to include more metals. Does the curious correlation between measured T{sub gas} and element boili

  10. {sup 99}Tc bioassay by inductively coupled plasma mass spectrometry (ICP-MS)

    SciTech Connect (OSTI)

    Lewis, L.A.

    1998-05-01T23:59:59.000Z

    A means of analyzing {sup 99}Tc in urine by inductively coupled plasma mass spectrometry (ICP-MS) has been developed. Historically, {sup 99}Tc analysis was based on the radiometric detection of the 293 keV E{sub Max} beta decay product by liquid scintillation or gas flow proportional counting. In a urine matrix, the analysis of{sup 99}Tc is plagued with many difficulties using conventional radiometric methods. Difficulties originate during chemical separation due to the volatile nature of Tc{sub 2}O{sub 7} or during radiation detection due to color or chemical quenching. A separation scheme for {sup 99}Tc detection by ICP-MS is given and is proven to be a sensitive and robust analytical alternative. A comparison of methods using radiometric and mass quantitation of {sup 99}Tc has been conducted in water, artificial urine, and real urine matrices at activity levels between 700 and 2,200 dpm/L. Liquid scintillation results based on an external standard quench correction and a quench curve correction method are compared to results obtained by ICP-MS. Each method produced accurate results, however the precision of the ICP-MS results is superior to that of liquid scintillation results. Limits of detection (LOD) for ICP-MS and liquid scintillation detection are 14.67 and 203.4 dpm/L, respectively, in a real urine matrix. In order to determine the basis for the increased precision of the ICP-MS results, the detection sensitivity for each method is derived and measured. The detection sensitivity for the {sup 99}Tc isotope by ICP-MS is 2.175 x 10{sup {minus}7} {+-} 8.990 x 10{sup {minus}9} and by liquid scintillation is 7.434 x 10{sup {minus}14} {+-} 7.461 x 10{sup {minus}15}. A difference by seven orders of magnitude between the two detection systems allows ICP-MS samples to be analyzed for a period of 15 s compared to 3,600 s by liquid scintillation counting with a lower LOD.

  11. Online tuning of impedance matching circuit for long pulse inductively coupled plasma source operation—An alternate approach

    SciTech Connect (OSTI)

    Sudhir, Dass; Bandyopadhyay, M., E-mail: mainak@ter-india.org; Chakraborty, A. [ITER-India, Institute for Plasma Research, A-29, GIDC, Sector-25, Gandhinagar, Gujarat 382 025 (India)] [ITER-India, Institute for Plasma Research, A-29, GIDC, Sector-25, Gandhinagar, Gujarat 382 025 (India); Kraus, W. [Max-Planck-Institut für Plasmaphysik, Boltzmannstrasse 2, 85740 Garching (Germany)] [Max-Planck-Institut für Plasmaphysik, Boltzmannstrasse 2, 85740 Garching (Germany); Gahlaut, A.; Bansal, G. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382 428 (India)] [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382 428 (India)

    2014-01-15T23:59:59.000Z

    Impedance matching circuit between radio frequency (RF) generator and the plasma load, placed between them, determines the RF power transfer from RF generator to the plasma load. The impedance of plasma load depends on the plasma parameters through skin depth and plasma conductivity or resistivity. Therefore, for long pulse operation of inductively coupled plasmas, particularly for high power (?100 kW or more) where plasma load condition may vary due to different reasons (e.g., pressure, power, and thermal), online tuning of impedance matching circuit is necessary through feedback. In fusion grade ion source operation, such online methodology through feedback is not present but offline remote tuning by adjusting the matching circuit capacitors and tuning the driving frequency of the RF generator between the ion source operation pulses is envisaged. The present model is an approach for remote impedance tuning methodology for long pulse operation and corresponding online impedance matching algorithm based on RF coil antenna current measurement or coil antenna calorimetric measurement may be useful in this regard.

  12. Modeling of inductively coupled plasma SF{sub 6}/O{sub 2}/Ar plasma discharge: Effect of O{sub 2} on the plasma kinetic properties

    SciTech Connect (OSTI)

    Pateau, Amand [Institut des Matériaux Jean Rouxel, Université de Nantes, 2 rue de la Houssiniére 44322 Nantes, France and ST Microelectronics, 10 rue Thals de Milet, 37071 Tours (France); Rhallabi, Ahmed, E-mail: ahmed.rhallabi@univ-nantes.fr; Fernandez, Marie-Claude [Institut des Matériaux Jean Rouxel, Université de Nantes, 2 rue de la Houssiniére 44322 Nantes (France); Boufnichel, Mohamed; Roqueta, Fabrice [ST Microelectronics, 10 rue Thales de Milet, 37071 Tours (France)

    2014-03-15T23:59:59.000Z

    A global model has been developed for low-pressure, inductively coupled plasma (ICP) SF{sub 6}/O{sub 2}/Ar mixtures. This model is based on a set of mass balance equations for all the considered species, coupled with the discharge power balance equation and the charge neutrality condition. The present study is an extension of the kinetic global model previously developed for SF{sub 6}/Ar ICP plasma discharges [Lallement et al., Plasma Sources Sci. Technol. 18, 025001 (2009)]. It is focused on the study of the impact of the O{sub 2} addition to the SF{sub 6}/Ar gas mixture on the plasma kinetic properties. The simulation results show that the electron density increases with the %O{sub 2}, which is due to the decrease of the plasma electronegativity, while the electron temperature is almost constant in our pressure range. The density evolutions of atomic fluorine and oxygen versus %O{sub 2} have been analyzed. Those atomic radicals play an important role in the silicon etching process. The atomic fluorine density increases from 0 up to 40% O{sub 2} where it reaches a maximum. This is due to the enhancement of the SF{sub 6} dissociation processes and the production of fluorine through the reactions between SF{sub x} and O. This trend is experimentally confirmed. On the other hand, the simulation results show that O(3p) is the preponderant atomic oxygen. Its density increases with %O{sub 2} until reaching a maximum at almost 40% O{sub 2}. Over this value, its diminution with O{sub 2}% can be justified by the high increase in the loss frequency of O(3p) by electronic impact in comparison to its production frequency by electronic impact with O{sub 2}.

  13. Measurement of low radioactivity background in a high voltage cable by high resolution inductively coupled plasma mass spectrometry

    SciTech Connect (OSTI)

    Vacri, M. L. di; Nisi, S.; Balata, M. [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)] [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)

    2013-08-08T23:59:59.000Z

    The measurement of naturally occurring low level radioactivity background in a high voltage (HV) cable by high resolution inductively coupled plasma mass spectrometry (HR ICP MS) is presented in this work. The measurements were performed at the Chemistry Service of the Gran Sasso National Laboratory. The contributions to the radioactive background coming from the different components of the heterogeneous material were separated. Based on the mass fraction of the cable, the whole contamination was calculated. The HR ICP MS results were cross-checked by gamma ray spectroscopy analysis that was performed at the low background facility STELLA (Sub Terranean Low Level Assay) of the LNGS underground lab using HPGe detectors.

  14. Development and evaluation of high resolution quadrupole mass analyzer and an inductively coupled plasma-Mach disk

    SciTech Connect (OSTI)

    Amad, Ma'an Hazem

    1999-12-10T23:59:59.000Z

    By definition a plasma is an electrically conducting gaseous mixture containing a significant concentration of cations and electrons. The Inductively Coupled Plasma (ICP) is an electrodeless discharge in a gas at atmospheric pressure. This discharge is an excellent one for vaporizing, atomizing, and ionizing elements. The early development of the ICP began in 1942 by Babat and then by Reed in the early 1960s. This was then followed by the pioneering work of Fassel and coworkers in the late 1960s. Commercial ICP spectrometers were introduced in the mid 1970s. A major breakthrough in the area of ICP took place in the early 1980s when the ICP was shown to be an excellent ion source for mass spectrometry.

  15. Low-temperature growth of gallium nitride films by inductively coupled-plasma-enhanced reactive magnetron sputtering

    SciTech Connect (OSTI)

    Ni, Chih-Jui; Chau-Nan Hong, Franklin, E-mail: hong@mail.ncku.edu.tw [Department of Chemical Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China)

    2014-05-15T23:59:59.000Z

    Gallium nitride (GaN) films were grown on sapphire substrate by reactive magnetron sputtering. Inductively coupled-plasma (ICP) source was installed between the substrate holder and the sputtering target to increase the plasma density and the degree of ionization of nitrogen gas. Liquid Ga and Ar/N{sub 2} were used as the sputtering target and sputtering gases, respectively. X-ray diffraction measurements confirmed that the authors could grow high quality GaN crystallites at 500?°C. However, the crystalline GaN (0002) peak remained even by lowering the growth temperature down to 300?°C. The N:Ga ratio of the film grown at 500?°C was almost 1:1, and the nitrogen composition became higher toward the 1:1 N:Ga ratio with increasing the growth temperature. The high degree of ionization induced by ICP source was essential to the growth of high crystalline quality GaN films.

  16. Non-invasive in situ plasma monitoring of reactive gases using the floating harmonic method for inductively coupled plasma etching application

    SciTech Connect (OSTI)

    Lee, J. H.; Kim, M. J. [Department of Materials Science and Engineering, University of Texas at Dallas, Texas 75080 (United States); Yoon, Y. S. [Department of Electrical Engineering, University of Texas at Dallas, Texas 75080 (United States)

    2013-04-15T23:59:59.000Z

    The floating harmonic method was developed for in situ plasma diagnostics of allowing real time measurement of electron temperature (T{sub e}) and ion flux (J{sub ion}) without contamination of the probe from surface modification by reactive species. In this study, this novel non-invasive diagnostic system was studied to characterize inductively coupled plasma of reactive gases monitoring T{sub e} and J{sub ion} for investigating the optimum plasma etching conditions and controlling of the real-time plasma surface reaction in the range of 200-900 W source power, 10-100 W bias power, and 3-15 mTorr chamber pressure, respectively.

  17. Determination of platinum and palladium in geologic samples by ion exchange chromatography with inductively coupled plasma atomic emission spectrometric detection

    SciTech Connect (OSTI)

    Brown, R.J.; Biggs, W.R.

    1984-04-01T23:59:59.000Z

    An alternative procedure to the classical fire assay method for determining Pt and Pd in sulfide ores, concentrates, and furnace mattes is presented. A suitable amount of sample is digested with aqua regla and filtered and any remaining gangue is digested with a mixture of HF and HClO/sub 4/. The solution is filtered and the residue fused with sodium peroxide granules. The fused salts are dissolved in a dilute HCl acid solution and all three solutions combined. The resultant solution is passed through a Bio-Rad AG 50W-X8 cation exchange resin in the H/sup +/ form. The chlorocomplex anions of Pt and Pd are not retained by the cation exchange resin while the base metal cations are efficiently removed from the eluent. Pt and Pd concentrations are subsequently determined with an inductively coupled plasma (ICP). Preliminary experiments showing the method's potential expandability to Au are included.

  18. Cl{sub 2}-based dry etching of the AlGaInN system in inductively coupled plasmas

    SciTech Connect (OSTI)

    Cho, Hyun; Vartuli, C.B.; Abernathy, C.R.; Donovan, S.M.; Pearton, S.J. [Florida Univ., Gainesville, FL (United States). Dept. of Materials Science and Engineering; Shul, R.J.; Han, J. [Sandia National Labs., NM (United States)

    1997-12-01T23:59:59.000Z

    Cl{sub 2}-based Inductively Coupled Plasmas with low additional dc self- biases(-100V) produce convenient etch rates(500-1500 A /min) for GaN, AlN, InN, InAlN and InGaN. A systematic study of the effects of additive gas(Ar, N{sub 2}, H{sub 2}), discharge composition and ICP source power and chuck power on etch rate and surface morphology has been performed. The general trends are to go through a maximum in etch rate with percent Cl{sub 2} in the discharge for all three mixtures, and to have an increase(decrease) in etch rate with source power(pressure). Since the etching is strongly ion-assisted, anisotropic pattern transfer is readily achieved. Maximum etch selectivities of approximately 6 for InN over the other nitrides were obtained.

  19. Inductively Coupled Plasma etching of amorphous silicon nanostructures over nanotopography using C4F8/SF6 chemistry

    E-Print Network [OSTI]

    Harvey-Collard, Patrick; Drouin, Dominique; Pioro-Ladrière, Michel; 10.1016/j.mee.2013.02.099

    2013-01-01T23:59:59.000Z

    Inductively Coupled Plasma (ICP) etching of amorphous silicon (a-Si) nanostructures using a continuous C4F8/SF6 plasma over nanotopography in silicon dioxide (SiO2) is investigated. The coil power of the ICP system is used to tune the a-Si etch rate from 20 to 125 nm/min. The etch rates of a-Si, SiO2 and electroresist are measured depending on the SF6 ratio, platen power and chamber pressure and used to optimize the a-Si:SiO2 etch selectivity. The results on nanostructures show that the presence of an insulating etch-stop layer affects the passivation ratio required to achieve vertical sidewalls. A low pressure is also necessary in order to etch the silicon nanostructure embedded into the oxide nanotrenches to form a highly conformable a-Si nanowire. We argue that both of these behaviors could be explained by surface charging effects. Finally, etching of 20 nm a-Si nanowires that cross 15 nm trenches in oxide with vertical sidewalls and a 4.3:1 a-Si:SiO2 etch selectivity is demonstrated. This etching process ...

  20. Radio frequency-power and the ring-mode to red-mode transition in an inductively coupled plasma

    SciTech Connect (OSTI)

    Coffer, J. G.; Camparo, J. C. [Physical Sciences Laboratories, The Aerospace Corporation, P.O. Box 92957, Los Angeles, California 90009 (United States)

    2012-04-15T23:59:59.000Z

    The optical output of an alkali-metal inductively coupled plasma (alkali-ICP) plays an important role in both atomic magnetometers and atomic clocks, producing these devices' atomic signals through optical pumping. Unfortunately, though the alkali-ICP's optical pumping efficiency grows exponentially with temperature, at relatively high temperatures ({approx}140 deg. C) the discharge transitions from ''ring mode'' to ''red mode'', which is a spectral change in the plasma's output that corresponds broadly to a transition from ''good emission'' for optical pumping to ''poor emission.'' Recently, evidence has accumulated pointing to radiation trapping as the mechanism driving the ring-mode to red-mode transition, suggesting that the phenomenon is primarily linked to the alkali vapor's temperature. However, observations of the transition made in the 1960 s, demonstrating that the ICP temperature associated with the transition depended on rf-power, would appear to cast doubt on this mechanism. Here, we carefully investigate the influence of rf-power on the ring-mode to red-mode transition, finding that rf-power only affects the transition through discharge heating. Thus, the present work shows that the primary effect of rf-power on the ring-mode to red-mode transition can be understood in terms of the radiation trapping mechanism.

  1. Etching kinetics and surface roughening of polysilicon and dielectric materials in inductively coupled plasma beams

    E-Print Network [OSTI]

    Yin, Yunpeng, Ph. D. Massachusetts Institute of Technology

    2007-01-01T23:59:59.000Z

    Plasma etching processes often roughen the feature sidewalls forming anisotropic striations. A clear understanding of the origin and control of sidewall roughening is extremely desirable, particularly at the gate level ...

  2. Improvements to Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh School footballHydrogenITLaboratory in Inductively Coupledfor

  3. A Parametric Study of Electron Extraction from a Low Frequency Inductively Coupled RF-Plasma Source

    E-Print Network [OSTI]

    -cathode is closed only by the ion current to the cathode chamber wall. The extraction of electrons from the rf through this opening is larger than the ion saturation current to the chamber wall, then the maximum by the plasma density in the cathode chamber, the ion Bohm velocity at the sheath edge and the surface area

  4. The effect of ultrafast laser wavelength on ablation properties and implications on sample introduction in inductively coupled plasma mass spectrometry

    SciTech Connect (OSTI)

    LaHaye, N. L.; Harilal, S. S.; Diwakar, P. K.; Hassanein, A. [Center for Materials under Extreme Environment, School of Nuclear Engineering Purdue University, West Lafayette, Indiana 47907 (United States); Kulkarni, P. [Centers for Disease Control and Prevention, National Institute of Occupational Safety and Health, Cincinnati, Ohio 45213 (United States)

    2013-07-14T23:59:59.000Z

    We investigated the role of femtosecond (fs) laser wavelength on laser ablation (LA) and its relation to laser generated aerosol counts and particle distribution, inductively coupled plasma-mass spectrometry (ICP-MS) signal intensity, detection limits, and elemental fractionation. Four different NIST standard reference materials (610, 613, 615, and 616) were ablated using 400 nm and 800 nm fs laser pulses to study the effect of wavelength on laser ablation rate, accuracy, precision, and fractionation. Our results show that the detection limits are lower for 400 nm laser excitation than 800 nm laser excitation at lower laser energies but approximately equal at higher energies. Ablation threshold was also found to be lower for 400 nm than 800 nm laser excitation. Particle size distributions are very similar for 400 nm and 800 nm wavelengths; however, they differ significantly in counts at similar laser fluence levels. This study concludes that 400 nm LA is more beneficial for sample introduction in ICP-MS, particularly when lower laser energies are to be used for ablation.

  5. RAPID DETERMINATION OF 237 NP AND PU ISOTOPES IN WATER BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY AND ALPHA SPECTROMETRY

    SciTech Connect (OSTI)

    Maxwell, S.; Jones, V.; Culligan, B.; Nichols, S.; Noyes, G.

    2010-06-23T23:59:59.000Z

    A new method that allows rapid preconcentration and separation of plutonium and neptunium in water samples was developed for the measurement of {sup 237}Np and Pu isotopes by inductively-coupled plasma mass spectrometry (ICP-MS) and alpha spectrometry; a hybrid approach. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via peak tailing. The method provide enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then moving Pu to DGA resin for additional removal of uranium. The decontamination factor for uranium from Pu is almost 100,000 and the decontamination factor for U from Np is greater than 10,000. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration is performed using a streamlined calcium phosphate precipitation method. Purified solutions are split between ICP-MS and alpha spectrometry so that long and short-lived Pu isotopes can be measured successfully. The method allows for simultaneous extraction of 20 samples (including QC samples) in 4 to 6 hours, and can also be used for emergency response. {sup 239}Pu, {sup 242}Pu and {sup 237}Np were measured by ICP-MS, while {sup 236}Pu, {sup 238}Pu, and {sup 239}Pu were measured by alpha spectrometry.

  6. DETERMINATION OF 237NP AND PU ISOTOPES IN LARGE SOIL SAMPLES BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY

    SciTech Connect (OSTI)

    Maxwell, S.

    2010-07-26T23:59:59.000Z

    A new method for the determination of {sup 237}Np and Pu isotopes in large soil samples has been developed that provides enhanced uranium removal to facilitate assay by inductively coupled plasma mass spectrometry (ICP-MS). This method allows rapid preconcentration and separation of plutonium and neptunium in large soil samples for the measurement of {sup 237}Np and Pu isotopes by ICP-MS. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via {sup 238}U peak tailing. The method provides enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then transferring Pu to DGA resin for additional purification. The decontamination factor for removal of uranium from plutonium for this method is greater than 1 x 10{sup 6}. Alpha spectrometry can also be applied so that the shorter-lived {sup 238}Pu isotope can be measured successfully. {sup 239}Pu, {sup 242}Pu and {sup 237}Np were measured by ICP-MS, while {sup 236}Pu and {sup 238}Pu were measured by alpha spectrometry.

  7. Standard test method for determination of impurities in nuclear grade uranium compounds by inductively coupled plasma mass spectrometry

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2010-01-01T23:59:59.000Z

    1.1 This test method covers the determination of 67 elements in uranium dioxide samples and nuclear grade uranium compounds and solutions without matrix separation by inductively coupled plasma mass spectrometry (ICP-MS). The elements are listed in Table 1. These elements can also be determined in uranyl nitrate hexahydrate (UNH), uranium hexafluoride (UF6), triuranium octoxide (U3O8) and uranium trioxide (UO3) if these compounds are treated and converted to the same uranium concentration solution. 1.2 The elements boron, sodium, silicon, phosphorus, potassium, calcium and iron can be determined using different techniques. The analyst's instrumentation will determine which procedure is chosen for the analysis. 1.3 The test method for technetium-99 is given in Annex A1. 1.4 The values stated in SI units are to be regarded as standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish ...

  8. NEW METHOD FOR REMOVAL OF SPECTRAL INTERFERENCES FOR BERYLLIUM ASSAY USING INDUCTIVELY COUPLED PLASMA ATOMIC EMISSION SPECTROMETRY

    SciTech Connect (OSTI)

    Maxwell, S; Matthew Nelson, M; Linda Youmans, L; Maureen Bernard, M

    2008-01-14T23:59:59.000Z

    Beryllium has been used widely in specific areas of nuclear technology. Frequent monitoring of air and possible contaminated surfaces in U.S Department of Energy (DOE) facilities is required to identify potential health risks and to protect DOE workers from beryllium-contaminated dust. A new method has been developed to rapidly remove spectral interferences prior to beryllium (Be) measurement by inductively-coupled plasma atomic emission spectrometry (ICP-AES). The ion exchange separation removes uranium (U), thorium (Th), niobium (Nb), vanadium (V), molybdenum (Mo), zirconium (Zr), tungsten (W), iron (Fe), chromium (Cr), cerium (Ce), erbium (Er) and titanium (Ti). A stacked column consisting of Diphonix Resin{reg_sign} and TEVA Resin{reg_sign} reduces the levels of the spectral interferences so that low level Be measurements can be performed accurately. If necessary, an additional anion exchange separation can be used for further removal of interferences, particularly chromium. The method has been tested using spiked filters, spiked wipe samples and certified reference material standards with high levels of interferences added. The method provides very efficient removal of spectral interferences with very good accuracy and precision for beryllium on filters or wipes. A vacuum box system is employed to reduce analytical time and reduce labor costs.

  9. Velocity distribution function of sputtered gallium atoms during inductively coupled argon plasma treatment of a GaAs surface

    SciTech Connect (OSTI)

    Despiau-Pujo, Emilie; Chabert, Pascal; Ramos, Raphaeel; Cunge, Gilles; Sadeghi, Nader [Laboratoire de Physique des Plasmas, Ecole Polytechnique, 91128 Palaiseau (France); Laboratoire des Technologies de la Microelectronique, CNRS, 38054 Grenoble (France)

    2009-03-15T23:59:59.000Z

    A GaN laser diode at 403.3 nm is used to measure the velocity distribution function (vdf) of Ga atoms sputtered from a radio-frequency biased GaAs substrate in a low pressure inductively coupled plasma (ICP) argon discharge. To investigate both perpendicular (V{sub z} normal to wafer) and longitudinal (V{sub x} parallel to wafer) velocity components, laser induced fluorescence (LIF) measurements are performed in the z direction and atomic absorption spectroscopy (AAS) in the x direction. The longitudinal vdf of Ga sputtered atoms is very close to a Lorentzian function with V{sub x} comprised between 0 and 7500 m s{sup -1}, while the perpendicular velocities V{sub z} can reach 10 000 m s{sup -1}. Experimental results are compared to molecular dynamics (MD) simulations of Ar{sup +} ion sputtering of GaAs under 200 eV bombardment. MD predictions and experiments are in fairly good agreement, which confirms the existence of products sputtered from the surface with kinetic energies larger than 10 eV. In etching processes dominated by physical bombardment, these energetic atoms could alter passivation layers on sidewalls and be responsible for defects observed in nanodevices. The best fit of the Doppler-broadened LIF and AAS profiles with the vdfs predicted by sputtering theory allows one to estimate the surface binding energy of Ga atoms in GaAs, E{sub b}, to be around 3 eV.

  10. RAPID DETERMINATION OF ACTINIDES IN URINE BY INDUCTIVELY-COUPLED PLASMA MASS SPECTROMETRY AND ALPHA SPECTROMETRY: A HYBRID APPROACH

    SciTech Connect (OSTI)

    Maxwell, S.; Jones, V.

    2009-05-27T23:59:59.000Z

    A new rapid separation method that allows separation and preconcentration of actinides in urine samples was developed for the measurement of longer lived actinides by inductively coupled plasma mass spectrometry (ICP-MS) and short-lived actinides by alpha spectrometry; a hybrid approach. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration, if required, is performed using a streamlined calcium phosphate precipitation. Similar technology has been applied to separate actinides prior to measurement by alpha spectrometry, but this new method has been developed with elution reagents now compatible with ICP-MS as well. Purified solutions are split between ICP-MS and alpha spectrometry so that long- and short-lived actinide isotopes can be measured successfully. The method allows for simultaneous extraction of 24 samples (including QC samples) in less than 3 h. Simultaneous sample preparation can offer significant time savings over sequential sample preparation. For example, sequential sample preparation of 24 samples taking just 15 min each requires 6 h to complete. The simplicity and speed of this new method makes it attractive for radiological emergency response. If preconcentration is applied, the method is applicable to larger sample aliquots for occupational exposures as well. The chemical recoveries are typically greater than 90%, in contrast to other reported methods using flow injection separation techniques for urine samples where plutonium yields were 70-80%. This method allows measurement of both long-lived and short-lived actinide isotopes. 239Pu, 242Pu, 237Np, 243Am, 234U, 235U and 238U were measured by ICP-MS, while 236Pu, 238Pu, 239Pu, 241Am, 243Am and 244Cm were measured by alpha spectrometry. The method can also be adapted so that the separation of uranium isotopes for assay is not required, if uranium assay by direct dilution of the urine sample is preferred instead. Multiple vacuum box locations may be set-up to supply several ICP-MS units with purified sample fractions such that a high sample throughput may be achieved, while still allowing for rapid measurement of short-lived actinides by alpha spectrometry.

  11. Direct analysis of samples by mass spectrometry: From elements to bio-molecules using laser ablation inductively couple plasma mass spectrometry and laser desorption/ionization mass spectrometry

    SciTech Connect (OSTI)

    Perdian, David C.

    2009-08-19T23:59:59.000Z

    Mass spectrometric methods that are able to analyze solid samples or biological materials with little or no sample preparation are invaluable to science as well as society. Fundamental research that has discovered experimental and instrumental parameters that inhibit fractionation effects that occur during the quantification of elemental species in solid samples by laser ablation inductively coupled plasma mass spectrometry is described. Research that determines the effectiveness of novel laser desorption/ionization mass spectrometric methods for the molecular analysis of biological tissues at atmospheric pressure and at high spatial resolution is also described. A spatial resolution is achieved that is able to analyze samples at the single cell level.

  12. Wafer heating mechanisms in a molecular gas, inductively coupled plasma: in situ, real time wafer surface measurements and three-dimensional thermal modeling

    SciTech Connect (OSTI)

    Titus, M. J.; Graves, D. B. [Department of Chemical Engineering, University of California, Berkeley, California 94720 (United States)

    2008-09-15T23:59:59.000Z

    The authors report measurements and modeling of wafer heating mechanisms in an Ar/O{sub 2} inductively coupled plasma (ICP). The authors employed a commercially available on-wafer sensor system (PlasmaTemp developed by KLA-Tencor) consisting of an on-board electronics module housing battery power and data storage with 30 temperature sensors embedded onto the wafer at different radial positions. This system allows for real time, in situ wafer temperature measurements. Wafer heating mechanisms were investigated by combining temperature measurements from the PlasmaTemp sensor wafer with a three-dimensional heat transfer model of the wafer and a model of the ICP. Comparisons between pure Ar and Ar/O{sub 2} discharges demonstrated that two additional wafer heating mechanisms can be important in molecular gas plasmas compared to atomic gas discharges. The two mechanisms are heating from the gas phase and O-atom surface recombination. These mechanisms were shown to contribute as much as 60% to wafer heating under conditions of low bias power. This study demonstrated how the 'on-wafer' temperature sensor not only yields a temperature profile distribution across the wafer, but can be used to help determine plasma characteristics, such as ion flux profiles or plasma processing temperatures.

  13. Inductively Coupled Plasma Etching in ICl- and IBr-Based Chemistries: Part II. InP, InSb, InGaP and InGaAs

    SciTech Connect (OSTI)

    Abernathy, C.R.; Cho, H.; Hahn, Y.B.; Hays, D.C.; Hobson, W.S.; Jung, K.B.; Lambers, E.S.; Pearton, S.J.; Shul, R.J.

    1998-11-23T23:59:59.000Z

    A parametric study of Inductively Coupled Plasma etching of InP, InSb, InGaP and InGaAs has been carried out in IC1/Ar and IBr/Ar chemistries. Etch rates in excess of 3.1 prrdmin for InP, 3.6 prnh-nin for InSb, 2.3 pm/min for InGaP and 2.2 ~rrdmin for InGaAs were obtained in IBr/Ar plasmas. The ICP etching of In-based materials showed a general tendency: the etch rates increased substantially with increasing the ICP source power and rf chuck power in both chemistries, while they decreased with increasing chamber pressure. The IBr/Ar chemistry typically showed higher etch rates than IC1/Ar, but the etched surface mophologies were fairly poor for both chemistries.

  14. Influence of the reactor wall composition on radicals' densities and total pressure in Cl{sub 2} inductively coupled plasmas: I. Without silicon etching

    SciTech Connect (OSTI)

    Cunge, G.; Sadeghi, N.; Ramos, R. [Laboratoire des Technologies de la Microelectronique, CNRS, 17 rue des Martyrs (c/o CEA-LETI), 38054 Grenoble Cedex 9 (France); Laboratoire de Spectrometrie Physique (UMR 5588), Universite Joseph Fourier-Grenoble, and CNRS, BP 87, 38402 St. Martin d'Heres (France); Laboratoire des Technologies de la Microelectronique, CNRS, 17 rue des Martyrs (c/o CEA-LETI), 38054 Grenoble Cedex 9 (France)

    2007-11-01T23:59:59.000Z

    Laser absorption at 355 nm is used to monitor the time variations of the Cl{sub 2} density in high-density industrial inductively coupled plasma. This technique is combined with the measurement of the gas temperature from the Doppler width of the 811.5 nm line of argon, added as a trace gas and with the measurement of the total gas pressure with a Baratron gauge. These measurements permit to estimate the mole fractions of Cl{sub 2} and Cl species in Cl{sub 2} inductively coupled plasmas in a waferless reactor. The impact of the chemical nature of the reactor wall coatings on the Cl and Cl{sub 2} mole fractions is studied systematically. We show that under otherwise identical plasma conditions, the Cl mole fraction is completely different when the plasma is operated in SiOCl, AlF, CCl, or TiOCl coated reactors, because the homogeneous recombination probability of Cl atoms is strongly surface dependant. The Cl atom mole fraction reached at 100 W radiofrequency power in SiOCl coated reactor (80%) is much higher than that obtained at 900 W in a ''clean'' AlF reactor (40%). A simple zero-dimensional model permits to provide the recombination coefficient of Cl atoms, {gamma}{sub rec}: 0.005 on SiOCl film and about 0.3 on the other three coatings. It is proposed to get benefit of this very high sensitivity of Cl{sub 2} dissociation rate to the wall coating for the control of the chamber wall status from the Cl{sub 2} density measurements in standard conditions.

  15. Effects of radio-frequency driving power, gas pressure, and nitrogen seeding on the transition dynamics in argon inductively coupled plasmas

    SciTech Connect (OSTI)

    Razzak, M. Abdur; Takamura, Shuichi; Uesugi, Yoshihiko [Department of Energy Engineering and Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Department of Electrical and Electronic Engineering, Kanazawa University 2-40-20 Kodatsuno, Ishikawa 920-8667 (Japan)

    2004-11-01T23:59:59.000Z

    The influences of rf driving power, neutral gas pressure, and nitrogen seeding on the electrostatic-to-electromagnetic (E-H) mode transition dynamics in radio-frequency argon inductively coupled plasmas (ICPs) in a pressure range of 50-100 kPa are investigated, both experimentally and theoretically. The E-H mode transition dynamics and its characteristic transition time scale are investigated by observing the high-speed imaging (13 500 fps) as well as the temporal change of plasma loading impedance. The experimental results reveal that the E-H mode transition time is not fixed at any operating conditions rather it depends on some important parameters such as the rf driving power, neutral gas pressure, gas type. It is found that the E-H mode transition time depends on the unique parameter E{sub {theta}}/p; the so-called effective induced electric field, rather than the independent parameter: the rf power or neutral gas pressure. It is also found that longer E-H mode transition time is required to ignite the high-pressure Ar-N{sub 2} plasmas with a 2.5%-10% N{sub 2} seeding than that of pure Ar plasmas with the same operating conditions. The experimental results are compared with that of the recently developed theoretical models, and a good agreement is found between them.

  16. Laser ablation-inductively coupled plasma-mass spectrometry: Examinations of the origins of polyatomic ions and advances in the sampling of particulates

    SciTech Connect (OSTI)

    Witte, Travis

    2011-11-30T23:59:59.000Z

    This dissertation provides a general introduction to Inductively coupled plasma-mass spectrometry (ICP-MS) and laser ablation (LA) sampling, with an examination of analytical challenges in the employment of this technique. It discusses the origin of metal oxide ions (MO+) in LA-ICP-MS, as well as the effect of introducing helium and nitrogen to the aerosol gas flow on the formation of these polyatomic interferences. It extends the study of polyatomic ions in LA-ICP-MS to metal argide (MAr+) species, an additional source of possible significant interferences in the spectrum. It describes the application of fs-LA-ICP-MS to the determination of uranium isotope ratios in particulate samples.

  17. Standard test method for the determination of impurities in plutonium metal: acid digestion and inductively coupled plasma-mass spectroscopy (ICP-MS) analysis

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2006-01-01T23:59:59.000Z

    1.1 This Test Method covers the determination of 58 trace elements in plutonium (Pu) metal. The Pu sample is dissolved in acid, and the concentration of the trace impurities are determined by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS). 1.2 This Test Method is specific for the determination of trace impurities in Pu metal. It may be applied to other types of Pu materials, such as Pu oxides, if the samples are dissolved and oxidized to the Pu(IV) state. However, it is the responsibility of the user to evaluate the performance of other matrices. 1.3 This standard does not purport to address all of the safety concerns associated with its use. It is the responsibility of the user of this method to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use of this standard.

  18. MAC581 Inductively Coupled Plasma Mass Spectrometry (http://www.rsmas.miami.edu/grad-studies/fall2010.html)

    E-Print Network [OSTI]

    Miami, University of

    nebulization, dissolvation, laser ablation, B. Tuning dry and wet plasma, sensitivity, stability, oxide, normal ICP torch and shield torch, cool plasma, RF generators, load coil and chiller, membrane cones, interface housing and cooling, slide valves, expansion chamber vacuum and pumps, ion kinetic

  19. Inductively coupled plasma spectrometry: Noise characteristics of aerosols, application of generalized standard additions method, and Mach disk as an emission source

    SciTech Connect (OSTI)

    Shen, Luan

    1995-10-06T23:59:59.000Z

    This dissertation is focused on three problem areas in the performance of inductively coupled plasma (ICP) source. The noise characteristics of aerosols produced by ICP nebulizers are investigated. A laser beam is scattered by aerosol and detected by a photomultiplier tube and the noise amplitude spectrum of the scattered radiation is measured by a spectrum analyzer. Discrete frequency noise in the aerosol generated by a Meinhard nebulizer or a direct injection nebulizer is primarily caused by pulsation in the liquid flow from the pump. A Scott-type spray chamber suppresses white noise, while a conical, straight-pass spray chamber enhances white noise, relative to the noise seen from the primary aerosol. Simultaneous correction for both spectral interferences and matrix effects in ICP atomic emission spectrometry (AES) can be accomplished by using the generalized standard additions method (GSAM). Results obtained with the application of the GSAM to the Perkin-Elmer Optima 3000 ICP atomic emission spectrometer are presented. The echelle-based polychromator with segmented-array charge-coupled device detectors enables the direct, visual examination of the overlapping lines Cd (1) 228.802 nm and As (1) 228.812 nm. The slit translation capability allows a large number of data points to be sampled, therefore, the advantage of noise averaging is gained. An ICP is extracted into a small quartz vacuum chamber through a sampling orifice in a water-cooled copper plate. Optical emission from the Mach disk region is measured with a new type of echelle spectrometer equipped with two segmented-array charge-coupled-device detectors, with an effort to improve the detection limits for simultaneous multielement analysis by ICP-AES.

  20. Comparative study of GaN mesa etch characteristics in Cl{sub 2} based inductively coupled plasma with Ar and BCl{sub 3} as additive gases

    SciTech Connect (OSTI)

    Rawal, Dipendra Singh, E-mail: dsrawal15@gmail.com; Arora, Henika; Sehgal, Bhupender Kumar; Muralidharan, Rangarajan [Solid State Physics Laboratory, Lucknow Road, Timarpur, Delhi-110054 (India)

    2014-05-15T23:59:59.000Z

    GaN thin film etching is investigated and compared for mesa formation in inductively coupled plasma (ICP) of Cl{sub 2} with Ar and BCl{sub 3} gas additives using photoresist mask. Etch characteristics are studied as a function of ICP process parameters, viz., ICP power, radio frequency (RF) power, and chamber pressure at fixed total flow rate. The etch rate at each ICP/RF power is 0.1–0.2??m/min higher for Cl{sub 2}/Ar mixture mainly due to higher Cl dissociation efficiency of Ar additive that readily provides Cl ion/radical for reaction in comparison to Cl{sub 2}/BCl{sub 3} mixture. Cl{sub 2}/Ar mixture also leads to better photoresist mask selectivity. The etch-induced roughness is investigated using atomic force microscopy. Cl{sub 2}/Ar etching has resulted in lower root-mean-square roughness of GaN etched surface in comparison to Cl{sub 2}/BCl{sub 3} etching due to increased Ar ion energy and flux with ICP/RF power that enhances the sputter removal of etch product. The GaN surface damage after etching is also evaluated using room temperature photoluminescence and found to be increasing with ICP/RF power for both the etch chemistries with higher degree of damage in Cl{sub 2}/BCl{sub 3} etching under same condition.

  1. A comparison of continuous pneumatic nebulization and flow injection-direct injection nebulization for sample introduction in inductively coupled plasma-mass spectrometry

    SciTech Connect (OSTI)

    Crain, J.S.; Kiely, J.T.

    1995-08-01T23:59:59.000Z

    Dilute nitric acid blanks and solutions containing Ni, Cd, Pb, and U (including two laboratory waste samples) were analyzed eighteen times over a two-month period using inductively coupled plasma-mass spectrometry (ICP-MS). Two different sample introduction techniques were employed: flow injection-direct injection nebulization (FI-DIN) and continuous pneumatic nebulization (CPN). Using comparable instrumental measurement procedures, FI-DIN analyses were 33% faster and generated 52% less waste than CPN analyses. Instrumental limits of detection obtained with FI-DIN and CPN were comparable but not equivalent (except in the case of Pb) because of nebulizer-related differences in sensitivity (i.e., signal per unit analyte concentration) and background. Substantial and statistically significant differences were found between FI-DIN and CPN Ni determinations, and in the case of the laboratory waste samples, there were also small but statistically significant differences between Cd determinations. These small (2 to 3%) differences were not related to polyatomic ion interference (e.g., {sup 95}Mo{sup 16}O{sup +}), but in light of the time savings and waste reduction to be realized, they should not preclude the use of FI-DIN in place of CPN for determination of Cd, Pb, U and chemically.

  2. Inductively coupled plasma etching of Si{sub 1-x}Ge{sub x} in CF{sub 4}/Ar and Cl{sub 2}/Ar discharges

    SciTech Connect (OSTI)

    Wu, S.-L.; Lee, C.-H.; Chang, S.-J.; Lin, Y.-M. [Department of Electronics Engineering, Cheng Shiu University, 840 Chengcing Road, Niaosong, Kaohsiung 833, Taiwan (China); Institute of Microelectronics, Department of Electrical Engineering, National Cheng Kung University, 1 Ta Hseuh Road, Tainan 701, Taiwan (China); Institute of Microelectronics, Department of Electrical Engineering, National Cheng Kung University, 1 Ta Hseuh Road, Tainan 701, Taiwan (China)

    2006-05-15T23:59:59.000Z

    In this article, we report the experimental realization of SiGe/Si materials using CF{sub 4}/Ar and Cl{sub 2}/Ar mixed-gas inductively coupled plasma (ICP) etching process. The effects of process parameters such as gas combination and gas species on etch rates and selectivities were investigated. It was found that samples in CF{sub 4} gas result in a faster etching rate than those obtained in Cl{sub 2} gas, which are responsible for a lower boiling point for Si-based fluoride. The lower boiling point provides more chemically active Si and SiGe materials. Moreover, the selectivity of 1.5 between Si{sub 0.3}Ge{sub 0.7}/Si by ICP technology was found and higher than that obtained previously by reactive ion etching reported in the literature. Based on these etch characteristics, the application of the ICP process to the device fabrication of SiGe doped-channel field-effect transistors was conducted. The devices using ICP mesa have excellent pinch-off characteristics with relatively low leakage current, small output conduction in the saturated region, and low knee voltage.

  3. Effects of magnetic flux density and substrate bias voltage on Ni films prepared on a flexible substrate material using unbalanced magnetron sputtering assisted by inductively coupled plasma

    SciTech Connect (OSTI)

    Koda, Tatsunori [Graduate School of Science and Technology, Hiroshima Institute of Technology, 2-1-1, Miyake, Saeki-ku, Hiroshima 7315193 (Japan); Toyota, Hiroshi, E-mail: h.toyota.za@it-hiroshima.ac.jp [Department of Electronics and Computer Engineering, Hiroshima Institute of Technology, 2-1-1, Miyake, Saeki-ku, Hiroshima 7315193 (Japan)

    2014-03-15T23:59:59.000Z

    The authors fabricated Ni films on a flexible substrate material using unbalanced magnetron sputtering assisted by inductively coupled plasma. The effects of magnetic flux density B{sub C} and substrate DC bias voltage V{sub S} on the Ni film structures were investigated. For V{sub S}?=??40?V, the average surface grain size D{sub G} measured by atomic force microscopy for B{sub C}?=?0, 3, and 5?mT was 88.2, 95.4, and 104.4?nm, respectively. In addition, D{sub G} increased with V{sub S}. From x-ray diffraction measurements, the (111) and (200) peaks were clearly visible for the fabricated Ni films. The ratio of the integrated intensities of I(111)/I(200) increased with V{sub S}. For V{sub S}?=??40?V and B{sub C}?=?3?mT, a film resistivity ? of 8.96?×?10{sup ?6} ? cm was observed, which is close to the Ni bulk value of 6.84?×?10{sup ?6} ? cm. From these results, the authors determined that the structure of the fabricated Ni films on the flexible substrate material was affected by the values of B{sub C} and V{sub S}.

  4. Performance Optimization Criteria for Pulsed Inductive Plasma Acceleration Kurt A. Polzin

    E-Print Network [OSTI]

    Choueiri, Edgar

    Performance Optimization Criteria for Pulsed Inductive Plasma Acceleration Kurt A. Polzin and Edgar Y. Choueiri Electric Propulsion and Plasma Dynamics Laboratory (EPPDyL) Mechanical and Aerospace A model of pulsed inductive plasma thrusters consisting of a set of coupled circuit equations and a one

  5. Influence of the reactor wall composition on radicals' densities and total pressure in Cl{sub 2} inductively coupled plasmas: II. During silicon etching

    SciTech Connect (OSTI)

    Cunge, G.; Sadeghi, N.; Ramos, R. [Laboratoire des Technologies de la Microelectronique, CNRS, 17 rue des Martyrs (c/o CEA-LETI), 38054 Grenoble Cedex 9 (France); Laboratoire de Spectrometrie Physique (UMR 5588), Universite Joseph Fourier-Grenoble, and CNRS, BP 87, 38402 St. Martin d'Heres (France); Laboratoire des Technologies de la Microelectronique, CNRS, 17 rue des Martyrs (c/o CEA-LETI), 38054 Grenoble Cedex 9 (France)

    2007-11-01T23:59:59.000Z

    In an industrial inductively coupled plasma reactor dedicated to silicon etching in chlorine-based chemistry, the density of Cl{sub 2} molecules and the gas temperature are measured by means of laser absorption techniques, the density of SiCl{sub x} (x{<=}2) radicals by broadband absorption spectroscopy, the density of SiCl{sub 4} and ions by mass spectrometry, and the total gas pressure with a capacitance gauge. These measurements permit us to estimate the mole fractions of Cl, SiCl{sub 4}, and etch product radicals when etching a 200 mm diameter silicon wafer. The pure Cl{sub 2} plasma is operated in well prepared chamber wall coating with a thin film of SiOCl, AlF, CCl, or TiOCl. The impact of the chemical nature of the reactor wall's coatings on these mole fractions is studied systematically. We show that the reactor wall coatings have a huge influence on the radicals densities, but this is not only from the difference on Cl-Cl recombination coefficient on different surfaces. During silicon etching, SiCl{sub x} radicals sticking on the reactor walls are etched by Cl atoms and recycled into the plasma by forming volatile SiCl{sub 4}. Hence, the loss of Cl atoms in etching the wall deposited silicon is at least as important as their wall recombination in controlling the Cl atoms density. Furthermore, because SiCl{sub 4} is produced at high rate by both the wafer and reactor walls, it is the predominant etching product in the gas phase. However, the percentage of redeposited silicon that can be recycled into the plasma depends on the amount of oxygen present in the plasma: O atoms produced by etching the quartz roof window fix Si on the reactor walls by forming a SiOCl deposit. Hence, the higher the O density is, the lower the SiCl{sub 4} density will be, because silicon is pumped by the reactor walls and the SiOCl layer formed is not isotropically etched by chlorine. As a result, in the same pure Cl{sub 2} plasma at 20 mTorr, the SiCl{sub x} mole fraction can vary from 18% in a SiOCl-coated reactor, where the O density is the highest, to 62% in a carbon-coated reactor, where there is no O. In the latter case, most of the Cl mass injected in the reactor is stored in SiCl{sub 4} molecules, which results in a low silicon etch rate. In this condition, the Cl mass balance is verified within 10%, and from the silicon mass balance we concluded that SiCl{sub x} radicals have a high surface loss probability. The impact of the reactor wall coating on the etching process is thus important, but the mechanisms by which the walls control the plasma chemistry is much more complicated than a simple control through recombination reaction of halogen atoms on these surfaces.

  6. Fabrication of ZnO photonic crystals by nanosphere lithography using inductively coupled-plasma reactive ion etching with CH{sub 4}/H{sub 2}/Ar plasma on the ZnO/GaN heterojunction light emitting diodes

    SciTech Connect (OSTI)

    Chen, Shr-Jia; Chang, Chun-Ming; Kao, Jiann-Shiun; Chen, Fu-Rong; Tsai, Chuen-Horng [Engineering and System Science, National Tsing Hua University, Hsinchu, 30013 Taiwan (China); Instrument Technology Research Center, National Applied Research Laboratories, Hsinchu, 300 Taiwan (China); Engineering and System Science, National Tsing Hua University, Hsinchu, 30013 Taiwan (China)

    2010-07-15T23:59:59.000Z

    This article reports fabrication of n-ZnO photonic crystal/p-GaN light emitting diode (LED) by nanosphere lithography to further booster the light efficiency. In this article, the fabrication of ZnO photonic crystals is carried out by nanosphere lithography using inductively coupled plasma reactive ion etching with CH{sub 4}/H{sub 2}/Ar plasma on the n-ZnO/p-GaN heterojunction LEDs. The CH{sub 4}/H{sub 2}/Ar mixed gas gives high etching rate of n-ZnO film, which yields a better surface morphology and results less plasma-induced damages of the n-ZnO film. Optimal ZnO lattice parameters of 200 nm and air fill factor from 0.35 to 0.65 were obtained from fitting the spectrum of n-ZnO/p-GaN LED using a MATLAB code. In this article, we will show our recent result that a ZnO photonic crystal cylinder has been fabricated using polystyrene nanosphere mask with lattice parameter of 200 nm and radius of hole around 70 nm. Surface morphology of ZnO photonic crystal was examined by scanning electron microscope.

  7. Coupling effects in inductive discharges with radio frequency substrate biasing

    SciTech Connect (OSTI)

    Schulze, J.; Schuengel, E.; Czarnetzki, U.

    2012-01-09T23:59:59.000Z

    Low pressure inductively coupled plasmas (ICP) operated in neon at 27.12 MHz with capacitive substrate biasing (CCP) at 13.56 MHz are investigated by phase resolved optical emission spectroscopy, voltage, and current measurements. Three coupling mechanisms are found potentially limiting the separate control of ion energy and flux: (i) Sheath heating due to the substrate biasing affects the electron dynamics even at high ratios of ICP to CCP power. At fixed CCP power, (ii) the substrate sheath voltage and (iii) the amplitude as well as frequency of plasma series resonance oscillations of the RF current are affected by the ICP power.

  8. Properties of C4F8 inductively coupled plasmas. I. Studies of Arc-C4F8 magnetically confined plasmas for etching of SiO2

    E-Print Network [OSTI]

    Kushner, Mark

    and CF3 ion fluxes increase, and CF3 becomes the dominant fluorocarbon ion. The ion energy distributions of passively deposited fluorocarbon films on Si, as measured by x-ray photoemission spectroscopy, differ little: 10.1116/1.1697482 I. INTRODUCTION Fluorocarbon plasmas are extensively used for etching

  9. Inductively generated streaming plasma ion source

    DOE Patents [OSTI]

    Glidden, Steven C.; Sanders, Howard D.; Greenly, John B.

    2006-07-25T23:59:59.000Z

    A novel pulsed, neutralized ion beam source is provided. The source uses pulsed inductive breakdown of neutral gas, and magnetic acceleration and control of the resulting plasma, to form a beam. The beam supplies ions for applications requiring excellent control of ion species, low remittance, high current density, and spatial uniformity.

  10. Plasma conductivity at finite coupling

    E-Print Network [OSTI]

    Babiker Hassanain; Martin Schvellinger

    2011-08-31T23:59:59.000Z

    By taking into account the full order(\\alpha'^3) type IIB string theory corrections to the supergravity action, we compute the leading finite 't Hooft coupling order(\\lambda^{-3/2}) corrections to the conductivity of strongly-coupled SU(N) {\\cal {N}}=4 supersymmetric Yang-Mills plasma in the large N limit. We find that the conductivity is enhanced by the corrections, in agreement with the trend expected from previous perturbative weak-coupling computations.

  11. Use of Electrodeposition for Sample Preparation and Rejection Rate Prediction for Assay of Electroformed Ultra High Purity Copper for 232Th and 238U Prior to Inductively Coupled Plasma Mass Spectrometry (ICP/MS)

    SciTech Connect (OSTI)

    Hoppe, Eric W.; Aalseth, Craig E.; Brodzinski, Ronald L.; Day, Anthony R.; Farmer, Orville T.; Hossbach, Todd W.; McIntyre, Justin I.; Miley, Harry S.; Mintzer, Esther E.; Seifert, Allen; Smart, John E.; Warren, Glen A.

    2008-07-01T23:59:59.000Z

    The search for neutrinoless double beta decay in 76Ge has driven the need for ultra-low background Ge detectors shielded by electroformed copper of ultra-high radiopurity (<0.1µBq/kg). Although electrodeposition processes are almost sophisticated enough to produce copper of this purity, to date there are no methods sensitive enough to assay it. Inductively-coupled plasma mass spectrometry (ICP/MS) can detect thorium and uranium at femtogram levels, but in the past, this assay has been hindered by high copper concentrations in the sample. Electrodeposition of copper samples removes copper from the solution while selectively concentrating thorium and uranium contaminants to be assayed by ICP/MS. Spiking 232Th and 238U into the plating bath simulates low purity copper and allows for the calculation of the electrochemical rejection rate of thorium and uranium in the electroplating system. This rejection value will help to model plating bath chemistry.

  12. Simulation results of an inductively-coupled rf plasma torch in two and three dimensions for producing a metal matrix composite for nuclear fuel cladding

    E-Print Network [OSTI]

    Holik III, Eddie Frank (Trey)

    2009-05-15T23:59:59.000Z

    I propose to develop a new method for the synthesis of metal matrix composites (MMC) using aerosol reactants in a radio frequency (RF) plasma torch. An inductivelycoupled RF plasma torch (ICPT) may potentially be designed to maintain laminar flow...

  13. Z .Thin Solid Films 374 2000 311 325 SiO etching in inductively coupled C F plasmas:2 2 6

    E-Print Network [OSTI]

    Economou, Demetre J.

    of silicon dioxide oxide over sili- con or silicon nitride using fluorocarbon plasmas is w xwidely known 1 6 . Fluorocarbon plasmas tend to pro- duce CF radicals that may polymerize on surfaces inx contact with the plasma either etching or polymer depo- sition are not well understood at present. Fluorocarbon chemistries have

  14. Kinetic Modeling of Halogen-Based Plasma Etching of Complex Oxide Films and its Application to Predictive Feature Profile Simulation

    E-Print Network [OSTI]

    Marchack, Nathan

    2012-01-01T23:59:59.000Z

    model for Si etching by fluorocarbon plasmas." Journal Ofwith inductively coupled fluorocarbon plasmas." Journal ofwith inductively coupled fluorocarbon plasmas." Journal of

  15. 2110 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 37, NO. 11, NOVEMBER 2009 Low-Pressure Helicon-Plasma Discharge Initiation

    E-Print Network [OSTI]

    Scharer, John E.

    -temperature plasma research. Low- pressure (as low as 1 millitorr) inductively coupled plasmas are used for plasma

  16. Transport of dust particles in inductively coupled discharges

    SciTech Connect (OSTI)

    Hwang, H.H.; Ventzek, P.L.G.; Hoekstra, R.; Kushner, M.J. [Univ. of Illinois, Urbana, IL (United States). Dept. of Electrical and Computer Engineering

    1994-12-31T23:59:59.000Z

    Contamination by particulates, or ``dust``, in plasma processing reactors decreases the yield of microelectronic components. In low temperature plasmas, such as those used in etching or deposition reactors to fabricate semiconductor devices, the particles can form to appreciable densities. These particles can be trapped or expelled from the reactor, depending on which forces dominate their transport. Quantities that affect dust motion in Inductively Coupled Plasma (ICP) discharges are the charge of the dust particles (electrostatic forces), momentum transfer with ions (viscous ion-drag forces), temperature gradients from heated electrodes (thermophoretic forces), and gas flow (fluid drag forces). The authors have developed a 2-D Monte Carlo simulation to investigate the trajectories of dust particles in ICP reactors. The model may have an arbitrary number and variety of dust species, and different gas mixtures may be used. The self-consistent electric fields, ion energy distributions, and species densities are imported from a companion Monte Carlo-fluid hybrid model. A semi-analytic model is used to determine the dust charge as well as the momentum transfer cross sections between dust and ions. The electrode topography can also affect the trapping locations of dust. Grooves on the electrodes perturb electrical forces and heated washers can change the thermophoretic forces; hence the spatial dust density varies from the case with a smooth, nonheated electrode. These effects on particle trapping will be presented. Other factors on trapping locations, such as dust particle size and varying power flow with time, will also be discussed.

  17. Temporal phenomena in inductively coupled chlorine and argon-chlorine discharges

    SciTech Connect (OSTI)

    Corr, C.S.; Steen, P.G.; Graham, W.G. [School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, Northern Ireland (United Kingdom)

    2005-04-04T23:59:59.000Z

    Reproducible modulations in low-pressure, inductively coupled discharges operating in chlorine and argon-chlorine mixtures have been observed and studied. Changes in the light output, floating potential, negative ion fraction, and charged particle densities were observed. Here we report two types of unstable operational modes in an inductively coupled discharge. On the one hand, when the discharge was matched, to minimize reflected power, instabilities were observed in argon-chlorine plasmas over limited operating conditions of input power and gas pressure. The instability window decreased with increasing chlorine content and was observed for chlorine concentrations between 30% and 60% only. However, when operating at pressures below 5 mTorr and the discharge circuit detuned to increase the reflected power, modulations were observed in a pure chlorine discharge. These modulations varied in nature from a series of sharp bursts to a very periodic behavior and can be controlled, by variation of the matching conditions, to produce an apparent pulsed plasma environment.

  18. Laser sampling system for an inductively-coupled atomic emission spectrometer. Final report

    SciTech Connect (OSTI)

    NONE

    1998-02-15T23:59:59.000Z

    A laser sampling system was attached to a Perkin Elmer Optima 3000 inductively-coupled plasma, atomic emission spectrometer that was already installed and operating in the Chemistry and Geochemistry Department at the Colorado School of Mines. The use of the spectrometer has been highly successful. Graduate students and faculty from at least four different departments across the CSM campus have used the instrument. The final report to NSF is appended to this final report. Appendices are included which summarize several projects utilizing this instrument: acquisition of an inductively-coupled plasma atomic emission spectrometer for the geochemistry program; hydrogen damage susceptibility assessment for high strength steel weldments through advanced hydrogen content analysis, 1996 and 1997 annual reports; and methods for determination of hydrogen distribution in high strength steel welds.

  19. Properties of c-C4F8 inductively coupled plasmas. II. Plasma chemistry and reaction mechanism for modeling of Arc-C4F8 O2 discharges

    E-Print Network [OSTI]

    Kushner, Mark

    to experiments for validation. The consequences of charge exchange of fluorocarbon species with Ar and CO on the ratio of light to heavy fluorocarbon ion densities in Ar/c-C4F8 /O2 /CO plasmas are discussed. We found but weakly depend on the addition of O2 . The ratio of light to heavy fluorocarbon ion densities increases

  20. Gauge/gravity duality and jets in strongly coupled plasma

    E-Print Network [OSTI]

    Paul M. Chesler

    2009-10-08T23:59:59.000Z

    We discuss jets in strongly coupled N = 4 supersymmetric Yang-Mills plasma and their dual gravitational description.

  1. Penetration of plasma into the wafer-focus ring gap in capacitively coupled plasmas

    E-Print Network [OSTI]

    Kushner, Mark

    Penetration of plasma into the wafer-focus ring gap in capacitively coupled plasmas Natalia Y of capacitively coupled plasma reactors with a wafer-focus ring gap. The penetration of plasma generated species i.e., ions and radicals into the wafer-focus ring gap is discussed. We found that the penetration of plasma

  2. Plasma and Fusion Research: Regular Articles Volume 2, 004 (2007) A Self-Organized Plasma with Induction, Reconnection, and

    E-Print Network [OSTI]

    Ji, Hantao

    the energy confinement time. Counter-helicity merging of inductively formed spheromaks is utilized to form toroid plasmas would be generated by the merging of co- and counter-helicity spheromaks produced

  3. SELECTIVE SIGNAL TRANSMISSION TO INLAID MICROCOILS BY INDUCTIVE COUPLING

    E-Print Network [OSTI]

    Wu, Jayne

    field, this problem has been approached by implanting and inductively powering a signal generator inside: (574) 631-4393, email: bernstein.1@nd.edu ABSTRACT Inductive links are widely used to power medical as a trans- cutaneous transformer, since its primary and secondary coils are physically separated

  4. Electric characteristics of a surface barrier discharge with a plasma induction electrode

    SciTech Connect (OSTI)

    Alemskii, I. N.; Lelevkin, V. M.; Tokarev, A. V.; Yudanov, V. A. [Kyrgyz-Russian Slavic University (Kyrgyzstan)

    2006-07-15T23:59:59.000Z

    Static and dynamic current-voltage and charge-voltage characteristics of a surface barrier discharge with a plasma induction electrode have been investigated experimentally. The dependences of the discharge current on both the gas pressure in the induction electrode tube and the winding pitch of the corona electrode, as well as of the discharge power efficiency on the applied voltage, have been measured.

  5. Plasma sweeper to control the coupling of RF power to a magnetically confined plasma

    DOE Patents [OSTI]

    Motley, Robert W. (Princeton, NJ); Glanz, James (Lawrenceville, NJ)

    1985-01-01T23:59:59.000Z

    A device for coupling RF power (a plasma sweeper) from a phased waveguide array for introducing RF power to a plasma having a magnetic field associated therewith comprises at least one electrode positioned near the plasma and near the phased waveguide array; and a potential source coupled to the electrode for generating a static electric field at the electrode directed into the plasma and having a component substantially perpendicular to the plasma magnetic field such that a non-zero vector cross-product of the electric and magnetic fields exerts a force on the plasma causing the plasma to drift.

  6. Rapid Wireless Capacitor Charging Using a Multi-Tapped Inductively-Coupled Secondary Coil

    E-Print Network [OSTI]

    Mercier, Patrick P.

    This paper presents an inductive coupling system designed to wirelessly charge ultra-capacitors used as energy storage elements. Although ultra-capacitors offer the native ability to rapidly charge, it is shown that standard ...

  7. Bulk viscosity of gauge theory plasma at strong coupling

    E-Print Network [OSTI]

    Alex Buchel

    2007-09-01T23:59:59.000Z

    We propose a lower bound on bulk viscosity of strongly coupled gauge theory plasmas. Using explicit example of the N=2^* gauge theory plasma we show that the bulk viscosity remains finite at a critical point with a divergent specific heat. We present an estimate for the bulk viscosity of QGP plasma at RHIC.

  8. Shock waves in strongly coupled plasmas

    SciTech Connect (OSTI)

    Khlebnikov, Sergei; Kruczenski, Martin; Michalogiorgakis, Georgios [Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, Indiana 47907 (United States)

    2010-12-15T23:59:59.000Z

    Shock waves are supersonic disturbances propagating in a fluid and giving rise to dissipation and drag. Weak shocks, i.e., those of small amplitude, can be well described within the hydrodynamic approximation. On the other hand, strong shocks are discontinuous within hydrodynamics and therefore probe the microscopics of the theory. In this paper, we consider the case of the strongly coupled N=4 plasma whose microscopic description, applicable for scales smaller than the inverse temperature, is given in terms of gravity in an asymptotically AdS{sub 5} space. In the gravity approximation, weak and strong shocks should be described by smooth metrics with no discontinuities. For weak shocks, we find the dual metric in a derivative expansion, and for strong shocks we use linearized gravity to find the exponential tail that determines the width of the shock. In particular, we find that, when the velocity of the fluid relative to the shock approaches the speed of light v{yields}1 the penetration depth l scales as l{approx}(1-v{sup 2}){sup 1/4}. We compare the results with second-order hydrodynamics and the Israel-Stewart approximation. Although they all agree in the hydrodynamic regime of weak shocks, we show that there is not even qualitative agreement for strong shocks. For the gravity side, the existence of shock waves implies that there are disturbances of constant shape propagating on the horizon of the dual black holes.

  9. Strongly Coupled Plasmas via Rydberg-Blockade of Cold Atoms

    E-Print Network [OSTI]

    Bannasch, G; Pohl, T

    2013-01-01T23:59:59.000Z

    We propose and analyze a new scheme to produce ultracold neutral plasmas deep in the strongly coupled regime. The method exploits the interaction blockade between cold atoms excited to high-lying Rydberg states and therefore does not require substantial extensions of current ultracold plasma experiments. Extensive simulations reveal a universal behavior of the resulting Coulomb coupling parameter, providing a direct connection between the physics of strongly correlated Rydberg gases and ultracold plasmas. The approach is shown to reduce currently accessible temperatures by more than an order of magnitude, which opens up a new regime for ultracold plasma research and cold ion-beam applications with readily available experimental techniques.

  10. Shear viscosity of CFT plasma at finite coupling

    E-Print Network [OSTI]

    Alex Buchel

    2008-05-29T23:59:59.000Z

    We present evidence for the universality of the shear viscosity of conformal gauge theory plasmas beyond infinite coupling. We comment of subtleties of computing the shear viscosity in effective models of gauge/gravity correspondence rather than in string theory.

  11. Kinetics and radiative processes in Xe/I{sub 2} inductively coupled rf discharges at low pressure

    SciTech Connect (OSTI)

    Barnes, P.N.; Verdeyen, J.T.; Kushner, M.J. [Univ. of Illinois, Urbana, IL (United States). Dept. of Electrical and Computer Engineering

    1996-12-31T23:59:59.000Z

    The environmental concern over the presence of mercury in conventional fluorescent lamps has motivated research into alternative electrically efficient near UV plasma lighting sources. One such candidate is multi-wavelength UV emission from Xe/I{sub 2} mixtures, including excimer radiation from XeI at 253 nm. Previous studies of the XeI system were performed at high pressures and were intended for laser applications. Practical Xe/I{sub 2} lamps will likely operate in the 0.5--10 torr regime and use electrodeless excitation to avoid issues related to electrode erosion by the halogen. In this paper, the authors report on an experimental investigation of low pressure, inductively coupled plasmas sustained in Xe/I{sub 2} mixtures. The goals of this work are to characterize the UV emission and determine excitation mechanisms in a parameter space of interest to lighting applications.

  12. Controlled synthesis of nickel ferrite nanocrystals with tunable properties using a novel induction thermal plasma method

    SciTech Connect (OSTI)

    Bastien, Samuel; Braidy, Nadi [Department of Chemical Engineering and Biotechnological Engineering, Université de Sherbrooke, Sherbrooke, Québec J1K 2R1 (Canada)

    2013-12-07T23:59:59.000Z

    Nickel ferrite spinel nanopowders were synthesised using a solution spray radio-frequency inductively coupled plasma reactor over a wide range of compositions (Ni{sub x}Fe{sub 3-x}O{sub 4}, x???1), with metastable powders produced for x?=?0, 0.25, and 0.5. X-ray fluorescence and X-ray diffraction coupled to Rietveld refinement show that this synthesis technique offers an excellent level of control over both the chemical and crystallographic composition of the nanopowder through the control of the input Fe/Ni ratio. The technique produces highly crystalline nanopowders without the need for post-synthesis annealing. A bulk Fe/Ni ratio ?2 yields a pure spinel Ni{sub x}Fe{sub 3-x}O{sub 4} phase, whereas Fe/Ni ratio <2 results in the excess Ni partitioning to a secondary bunsenite (Ni{sub x},Fe{sub 1-x})O phase. Morphological analysis using transmission electron microscopy shows that two types of particles are produced in different parts of the reactor: a highly faceted powder with the truncated octahedron morphology and a smaller-sized random agglomerate. The faceted particles have a log-normal particle size distribution, with an average size of about 30?nm while the agglomerates have a characteristic length of ?3–5?nm.

  13. Shear viscosity of boost invariant plasma at finite coupling

    E-Print Network [OSTI]

    Alex Buchel

    2008-03-04T23:59:59.000Z

    We discuss string theory alpha' corrections in the dual description of the expanding boost invariant N=4 supersymmetric Yang-Mills plasma at strong coupling. We compute finite 't Hooft coupling corrections to the shear viscosity and find that it disagrees with the equilibrium correlation function computations. We comment on the possible source of the discrepancy.

  14. Theory and Observations of Low Frequency Eigenmodes due to Alfvén Acoustic Coupling in Toroidal Fusion Plasmas

    E-Print Network [OSTI]

    Theory and Observations of Low Frequency Eigenmodes due to Alfvén Acoustic Coupling in Toroidal Fusion Plasmas

  15. Local fields in strongly coupled plasmas

    SciTech Connect (OSTI)

    Pollock, E.L.; Weisheit, J.C.

    1984-06-01T23:59:59.000Z

    Computer simulation techniques and important static properties of plasma microfields are discussed. The relevant timescales are introduced for dynamical atomic problems, and some time-dependent properties of microfields are discussed. In the last two sections of the paper these results are applied to two problems relevant to the spectroscopy of dense plasmas: (1) broadening of spectral lines, and (2) screening in inelastic electron-ion collisions.

  16. Mass Spectrometer: Inductively Coupled Plasma (ICP-MS), High...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    will be deployed in conjunction with the Neptune and can be used with the supplementary laser ablation unit to provide elemental concentrations at extremely small ablation spot...

  17. Mass Spectrometer: Inductively Coupled Plasma (ICP-MS), Multi...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    scientific communities. In addition, EMSL has initiated the process to purchase a custom laser ablation unit with an image size of 1 micron that in combination with the Neptune...

  18. Improvements to Laser Ablation-Inductively Coupled Plasma-Mass...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of trace element evidence to different materials (e.g., glass panes, metals, plastics, tapes) of forensic interest. Short validation studies to investigate the potential...

  19. Effect of strongly coupled plasma on photoionization cross section

    SciTech Connect (OSTI)

    Das, Madhusmita, E-mail: msdas@barc.gov.in [Department of Physics, Indian Institute of Technology, Powai, Mumbai 400076, India and Theoretical Physics Division, Bhabha Atomic Research Center, Mumbai 400085 (India)] [Department of Physics, Indian Institute of Technology, Powai, Mumbai 400076, India and Theoretical Physics Division, Bhabha Atomic Research Center, Mumbai 400085 (India)

    2014-01-15T23:59:59.000Z

    The effect of strongly coupled plasma on the ground state photoionization cross section is studied. In the non relativistic dipole approximation, cross section is evaluated from bound-free transition matrix element. The bound and free state wave functions are obtained by solving the radial Schrodinger equation with appropriate plasma potential. We have used ion sphere potential (ISP) to incorporate the plasma effects in atomic structure calculation. This potential includes the effect of static plasma screening on nuclear charge as well as the effect of confinement due to the neighbouring ions. With ISP, the radial equation is solved using Shooting method approach for hydrogen like ions (Li{sup +2}, C{sup +5}, Al{sup +12}) and lithium like ions (C{sup +3}, O{sup +5}). The effect of strong screening and confinement is manifested as confinement resonances near the ionization threshold for both kinds of ions. The confinement resonances are very much dependent on the edge of the confining potential and die out as the plasma density is increased. Plasma effect also results in appearance of Cooper minimum in lithium like ions, which was not present in case of free lithium like ions. With increasing density the position of Cooper minimum shifts towards higher photoelectron energy. The same behaviour is also true for weakly coupled plasma where plasma effect is modelled by Debye-Huckel potential.

  20. Viscoelastic modes in a strongly coupled, cold, magnetized dusty plasma

    SciTech Connect (OSTI)

    Banerjee, Debabrata; Mylavarapu, Janaki Sita; Chakrabarti, Nikhil [Saha Institute of Nuclear Physics, I/AF Bidhannagar, Calcutta 700 064 (India)

    2010-11-15T23:59:59.000Z

    A generalized hydrodynamical model has been used to study the low frequency modes in a strongly coupled, cold, magnetized dusty plasma. Such plasmas exhibit elastic properties due to the strong correlations among dust particles and the tensile stresses imparted by the magnetic field. It has been shown that longitudinal compressional Alfven modes and elasticity modified transverse shear mode exist in such a medium. The features of these collective modes are established and discussed.

  1. Parton picture for the strongly coupled SYM plasma

    E-Print Network [OSTI]

    E. Iancu

    2008-05-27T23:59:59.000Z

    Deep inelastic scattering off the strongly coupled N=4 supersymmetric Yang-Mills plasma at finite temperature can be computed within the AdS/CFT correspondence, with results which are suggestive of a parton picture for the plasma. Via successive branchings, essentially all partons cascade down to very small values of the longitudinal momentum fraction x and to transverse momenta smaller than the saturation momentum Q_s\\sim T/x. This scale Q_s controls the plasma interactions with a hard probe, in particular, the jet energy loss and its transverse momentum broadening.

  2. Model for a transformer-coupled toroidal plasma source

    SciTech Connect (OSTI)

    Rauf, Shahid; Balakrishna, Ajit; Chen Zhigang; Collins, Ken [Applied Materials, Inc., 974 E. Arques Avenue, Sunnyvale, California 94085 (United States)

    2012-01-15T23:59:59.000Z

    A two-dimensional fluid plasma model for a transformer-coupled toroidal plasma source is described. Ferrites are used in this device to improve the electromagnetic coupling between the primary coils carrying radio frequency (rf) current and a secondary plasma loop. Appropriate components of the Maxwell equations are solved to determine the electromagnetic fields and electron power deposition in the model. The effect of gas flow on species transport is also considered. The model is applied to 1 Torr Ar/NH{sub 3} plasma in this article. Rf electric field lines form a loop in the vacuum chamber and generate a plasma ring. Due to rapid dissociation of NH{sub 3}, NH{sub x}{sup +} ions are more prevalent near the gas inlet and Ar{sup +} ions are the dominant ions farther downstream. NH{sub 3} and its by-products rapidly dissociate into small fragments as the gas flows through the plasma. With increasing source power, NH{sub 3} dissociates more readily and NH{sub x}{sup +} ions are more tightly confined near the gas inlet. Gas flow rate significantly influences the plasma characteristics. With increasing gas flow rate, NH{sub 3} dissociation occurs farther from the gas inlet in regions with higher electron density. Consequently, more NH{sub 4}{sup +} ions are produced and dissociation by-products have higher concentrations near the outlet.

  3. Suppression of Rayleigh Taylor instability in strongly coupled plasmas

    SciTech Connect (OSTI)

    Das, Amita; Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2014-06-15T23:59:59.000Z

    The Rayleigh Taylor instability in a strongly coupled plasma medium has been investigated using the equations of generalized hydrodynamics. It is demonstrated that the visco-elasticity of the strongly coupled medium due to strong inter particle correlations leads to a suppression of the Rayleigh Taylor instability unless certain threshold conditions are met. The relevance of these results to experiments on laser compression of matter to high densities including those related to inertial confinement fusion using lasers has also been shown.

  4. Plasma Diagnostics and Plasma-Surface Interactions in Inductively Coupled Plasmas

    E-Print Network [OSTI]

    Titus, Monica Joy

    2010-01-01T23:59:59.000Z

    deposition and chamber pressure effects on the ion currentsignificant change in ion current at the chamber wall is nottotal positive ion current to the chamber surfaces 33 ; and

  5. Plasma Diagnostics and Plasma-Surface Interactions in Inductively Coupled Plasmas

    E-Print Network [OSTI]

    Titus, Monica Joy

    2010-01-01T23:59:59.000Z

    are protected with a layer of polyimide coating and theplasma (ICP) chamber. Polyimide Coating Electronic Moduleprotected with a layer of polyimide coating and communicate

  6. Plasma Diagnostics and Plasma-Surface Interactions in Inductively Coupled Plasmas

    E-Print Network [OSTI]

    Titus, Monica Joy

    2010-01-01T23:59:59.000Z

    3-dimensional heat transfer model of the wafer. Comparisonssensor wafer with a 3D heat transfer model of the wafer andTM sensor wafer with a 3D heat transfer model of the wafer.

  7. An experimental study and modeling of Transformer-Coupled Toroidal Plasma processing of materials

    E-Print Network [OSTI]

    Bai, Bo, Ph. D. Massachusetts Institute of Technology

    2006-01-01T23:59:59.000Z

    The Transformer Coupled Toroidal Plasma (TCTP) source uses a high power density plasma formed in a toroidal-shaped chamber by transformer coupling using a magnetic core. The objectives of the thesis are (1) to characterize ...

  8. Component Framework for Coupled Integrated Fusion Plasma Simulation

    SciTech Connect (OSTI)

    Elwasif, Wael R [ORNL; Bernholdt, David E [ORNL; Berry, Lee A [ORNL; Batchelor, Donald B [ORNL

    2007-01-01T23:59:59.000Z

    Fusion Successful simulation of the complex physics that affect magnetically confined fusion plasma remains an important target milestone towards the development of viable fusion energy. Major advances in the underlying physics formulations, mathematical modeling, and computational tools and techniques are needed to enable a complete fusion simulation on the emerging class of large scale capability parallel computers that are coming on-line in the next few years. Several pilot projects are currently being undertaken to explore different (partial) code integration and coupling problems, and possible solutions that may guide the larger integration endeavor. In this paper, we present the design and implementation details of one such project, a component based approach to couple existing codes to model the interaction between high power radio frequency (RF) electromagnetic waves, and magnetohydrodynamics (MHD) aspects of the burning plasma. The framework and component design utilize a light coupling approach based on high level view of constituent codes that facilitates rapid incorporation of new components into the integrated simulation framework. The work illustrates the viability of the light coupling approach to better understand physics and stand-alone computer code dependencies and interactions, as a precursor to a more tightly coupled integrated simulation environment.

  9. Photon noise limited radiation detection with lens-antenna coupled Microwave Kinetic Inductance Detectors

    E-Print Network [OSTI]

    Yates, S J C; Endo, A; Janssen, R M J; Ferrari, L; Diener, P; Baryshev, A M

    2011-01-01T23:59:59.000Z

    Microwave Kinetic Inductance Detectors (MKIDs) have shown great potential for sub-mm instrumentation because of the high scalability of the technology. Here we demonstrate for the first time in the sub-mm band (0.1...2 mm) a photon noise limited performance of a small antenna coupled MKID detector array and we describe the relation between photon noise and MKID intrinsic generation-recombination noise. Additionally we use the observed photon noise to measure the optical efficiency of detectors to be 0.8+-0.2.

  10. Title of Document: PLASMA ETCHING OF DIELECTIRC MATERIALS USING INDUCTIVELY AND

    E-Print Network [OSTI]

    Anlage, Steven

    AND CAPACITIVELY COUPLED FLUOROCARBON DISCHARGES: MECHANISTIC STUDIES OF THE SURFACE CHEMISTRY Li Ling, Doctor Fluorocarbon (FC) plasmas are commonly used for dielectric materials etching. Our initial work was performed-interaction with the photoresist material by fluorocarbon surface passivation, may be responsible for the introduction

  11. Exact propagating nonlinear singular disturbances in strongly coupled dusty plasmas

    SciTech Connect (OSTI)

    Das, Amita; Tiwari, Sanat Kumar; Kaw, Predhiman; Sen, Abhijit [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

    2014-08-15T23:59:59.000Z

    The dynamical response of the strongly coupled dusty plasma medium has recently been described by utilizing the Generalized Hydrodynamic (GHD) model equations. The GHD equations capture the visco-elastic properties of the medium and have been successful in predicting a host of phenomena (e.g., existence of novel transverse shear waves in the fluid medium, modification of longitudinal wave dispersion by elastic effects, etc.) which have found experimental confirmation. In this paper, the nonlinear longitudinal response of the medium governed by GHD equations in strong coupling limit is discussed analytically. The structure of the equations rules out the balance between dispersion and nonlinearity, thereby, forbidding soliton formation. However, a host of new varieties of nonlinear solutions are found to exist, which have singular spatial profiles and yet have conservative properties. For instance, existence of novel conservative shock structures with zero strength is demonstrated, waves whose breaking produces no dissipation in the medium are observed, propagating solutions which produce cusp like singularities can exist and so on. It is suggested that simulations and experiments should look for these novel nonlinear structures in the large amplitude strong coupling limit of longitudinal disturbances in dusty plasmas.

  12. The energetic coupling of scales in gyrokinetic plasma turbulence

    SciTech Connect (OSTI)

    Teaca, Bogdan, E-mail: bogdan.teaca@coventry.ac.uk [Applied Mathematics Research Centre, Coventry University, Coventry CV1 5FB (United Kingdom); Max-Planck für Sonnensystemforschung, Justus-von-Liebig-Weg 3, D-37077 Göttingen (Germany); Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany); Max-Planck/Princeton Center for Plasma Physics (Germany); Navarro, Alejandro Bañón, E-mail: alejandro.banon.navarro@ipp.mpg.de [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany); Jenko, Frank, E-mail: frank.jenko@ipp.mpg.de [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany); Max-Planck/Princeton Center for Plasma Physics (Germany)

    2014-07-15T23:59:59.000Z

    In magnetized plasma turbulence, the couplings of perpendicular spatial scales that arise due to the nonlinear interactions are analyzed from the perspective of the free-energy exchanges. The plasmas considered here, with appropriate ion or electron adiabatic electro-neutrality responses, are described by the gyrokinetic formalism in a toroidal magnetic geometry. Turbulence develops due to the electrostatic fluctuations driven by temperature gradient instabilities, either ion temperature gradient (ITG) or electron temperature gradient (ETG). The analysis consists in decomposing the system into a series of scale structures, while accounting separately for contributions made by modes possessing special symmetries (e.g., the zonal flow modes). The interaction of these scales is analyzed using the energy transfer functions, including a forward and backward decomposition, scale fluxes, and locality functions. The comparison between the ITG and ETG cases shows that ETG turbulence has a more pronounced classical turbulent behavior, exhibiting a stronger energy cascade, with implications for gyrokinetic turbulence modeling.

  13. Charmonium in strongly coupled quark-gluon plasma

    E-Print Network [OSTI]

    Clint Young; Edward Shuryak

    2008-09-22T23:59:59.000Z

    The growing consensus that a strongly-coupled quark-gluon plasma (sQGP) has been observed at the SPS and RHIC experiments suggests a different framework for examining heavy quark dynamics. We present both semi-analytical treatment of Fokker-Planck (FP) evolution in pedagogical examples and numerical Langevin simulations of evolving charm quark-antiquark pairs on top of a hydrodynamically expanding fireball. In this way, we may conclude that the survival probability of bound charmonia states is greater than previously estimated, as the spatial equilibration of pairs proceeds through a ``slowly dissolving lump'' stage related to the pair interaction.

  14. Bulk viscosity of strongly coupled plasmas with holographic duals

    E-Print Network [OSTI]

    Steven S. Gubser; Silviu S. Pufu; Fabio D. Rocha

    2008-06-02T23:59:59.000Z

    We explain a method for computing the bulk viscosity of strongly coupled thermal plasmas dual to supergravity backgrounds supported by one scalar field. Whereas earlier investigations required the computation of the leading dissipative term in the dispersion relation for sound waves, our method requires only the leading frequency dependence of an appropriate Green's function in the low-frequency limit. With a scalar potential chosen to mimic the equation of state of QCD, we observe a slight violation of the lower bound on the ratio of the bulk and shear viscosities conjectured in arXiv:0708.3459.

  15. Non-inductive Solenoid-less Plasma Current Start-up in NSTX Using Transient CHI

    SciTech Connect (OSTI)

    Raman, R; Jarboe, T R; Nelson, B A; Bell, M G; Ono, M; Bigelow, T; Kaita, R; LeBlanc, B; Lee, K C; Maqueda, R; Menard, J; Paul, S

    2007-05-23T23:59:59.000Z

    Coaxial Helicity Injection (CHI) has been successfully used in the National Spherical Torus Experiment (NSTX) for a demonstration of closed flux current generation without the use of the central solenoid. The favorable properties of the Spherical Torus (ST) arise from its very small aspect ratio. However, small aspect ratio devices have very restricted space for a substantial central solenoid. Thus methods for initiating the plasma current without relying on induction from a central solenoid are essential for the viability of the ST concept. CHI is a promising candidate for solenoid-free plasma startup in a ST. The method has now produced closed flux current up to 160 kA verifying the high current capability of this method in a large ST built with conventional tokamak components.

  16. The Weibel instability in a strongly coupled plasma

    SciTech Connect (OSTI)

    Mahdavi, M., E-mail: m.mahdavi@umz.ac.ir; Khanzadeh, H. [Physics Department, University of Mazandaran, P. O. Box 47415-416, Babolsar (Iran, Islamic Republic of)

    2014-06-15T23:59:59.000Z

    In this paper, the growth rate of the Weibel instability is calculated for an energetic relativistic electron beam penetrated into a strongly coupled plasma, where the collision effects of background electron-ion scattering play an important role in equations. In order to calculate the growth rate of the Weibel instability, two different models of anisotropic distribution function are used. First, the distribution of the plasma and beam electrons considered as similar forms of bi-Maxwellian distribution. Second, the distribution functions of the plasma electrons and the beam electrons follows bi-Maxwellian and delta-like distributions, respectively. The obtained results show that the collision effect decreases the growth rate in two models. When the distribution function of electrons beam is in bi-Maxwellian form, the instability growth rate is greater than where the distribution function of beam electrons is in delta-like form, because, the anisotropic temperature for bi-Maxwellian distribution function in velocity space is greater than the delta-like distribution function.

  17. Apparatus having inductively coupled coaxial coils for measuring buildup of slay or ash in a furnace

    DOE Patents [OSTI]

    Mathur, Mahendra P. (Pittsburgh, PA); Ekmann, James M. (Bethel Park, PA)

    1989-01-01T23:59:59.000Z

    The buildup of slag or ash on the interior surface of a furnace wall is monitored by disposing two coils to form a transformer which is secured adjacent to the inside surface of the furnace wall. The inductive coupling between the two coils of the transformer is affected by the presence of oxides of iron in the slag or ash which is adjacent to the transformer, and the application of a voltage to one winding produces a voltage at the other winding that is related to the thickness of the slag or ash buildup on the inside surface of the furnace wall. The output of the other winding is an electrical signal which can be used to control an alarm or the like or provide an indication of the thickness of the slag or ash buildup at a remote location.

  18. Diagnostics and modeling of plasma processes in ion sources

    E-Print Network [OSTI]

    Vertes, Akos

    radiation (inductively coupled plasma (ICI'), microwave-induced plasma (MU'), pulsed laser). The present-8), radiofrequency (9) and microwave ion sources (10-12) are under intense investigation. Diligent research

  19. Dense strongly coupled plasma in double laser pulse ablation of lithium: Experiment and simulation

    SciTech Connect (OSTI)

    Kumar, Ajai; Sivakumaran, V.; Ganesh, R.; Joshi, H. C. [Institute for Plasma Research, Bhat, Gandhinagar-382428 (India)] [Institute for Plasma Research, Bhat, Gandhinagar-382428 (India); Ashwin, J. [Weizmann Institute of Science, Rehovot - 76100 (Israel)] [Weizmann Institute of Science, Rehovot - 76100 (Israel)

    2013-08-15T23:59:59.000Z

    In a simple method of low power nano-second double pulsed laser ablation experiment in collinear geometry, formation of high density strongly coupled plasma is demonstrated. Using time-resolved measurements of the Stark broadened line width and line intensity ratio of the emission lines, the density and temperature of the plasma were estimated respectively. In this experiment, it is shown that ions are strongly coupled (ion-ion coupling parameter comes out to be >4). For comparison, both single and double pulsed laser ablations are presented. For the estimated experimental plasma parameters, first principle Langevin dynamics simulation corroborates the existence of a strongly coupled regime.

  20. Pulsed, Inductively Generated, Streaming Plasma Ion Source for Heavy Ion Fusion Linacs

    SciTech Connect (OSTI)

    Steven C. Glidden; Howard D Sanders; John B. Greenly; Daniel L. Dongwoo

    2006-04-28T23:59:59.000Z

    This report describes a compact, high current density, pulsed ion source, based on electrodeless, inductively driven gas breakdown, developed to meet the requirements on normalized emittance, current density, uniformity and pulse duration for an ion injector in a heavy-ion fusion driver. The plasma source produces >10 ?s pulse of Argon plasma with ion current densities >100 mA/cm2 at 30 cm from the source and with strongly axially directed ion energy of about 80 eV, and sub-eV transverse temperature. The source has good reproducibility and spatial uniformity. Control of the current density during the pulse has been demonstrated with a novel modulator coil method which allows attenuation of the ion current density without significantly affecting the beam quality. This project was carried out in two phases. Phase 1 used source configurations adapted from light ion sources to demonstrate the feasibility of the concept. In Phase 2 the performance of the source was enhanced and quantified in greater detail, a modulator for controlling the pulse shape was developed, and experiments were conducted with the ions accelerated to >40 kV.

  1. Kolmogorov flow in two dimensional strongly coupled dusty plasma

    SciTech Connect (OSTI)

    Gupta, Akanksha; Ganesh, R., E-mail: ganesh@ipr.res.in; Joy, Ashwin [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 382 428 (India)

    2014-07-15T23:59:59.000Z

    Undriven, incompressible Kolmogorov flow in two dimensional doubly periodic strongly coupled dusty plasma is modelled using generalised hydrodynamics, both in linear and nonlinear regime. A complete stability diagram is obtained for low Reynolds numbers R and for a range of viscoelastic relaxation time ?{sub m} [0?

  2. Testing of inductively coupled Eddy current position sensor of diverse safety rod in sodium

    SciTech Connect (OSTI)

    Vijayashree, R.; Veeraswamy, R.; Nashine, B. K.; Dash, S. K.; Sharma, P.; Rajan, K. K.; Vijayakumar, G.; Rao, C. B.; Sosamma, S.; Kalyanasundaram, P. [Indira Gandhi Centre for Atomic Research, Dept. of Atomic Energy, Kalpakkam - 603 102 (India)

    2011-07-01T23:59:59.000Z

    Prototype Fast Breeder Reactor (PFBR) is 500 MWe sodium cooled reactor under construction at Kalpakkam (India)). To improve the reliability of shutdown, Diverse Safety Rods (DSRs) are used in-addition to normal Control and Safety rods. During reactor operating condition, the DSR is parked above the active core and held in its top position by an electromagnet. In the event of a scram signal from the safety logic, the electromagnet holding the DSR is de-energised. Hence the DSR is released into the active core and at the end of travel DSR gets deposited in its bottom position. Because of the mechanical constraints, hard wired connectivity is not permitted from the DSR subassembly to the instrumentation outside the reactor. Hence an inductively coupled Eddy Current Position Sensor (ECPS) has been conceptualized to detect that the DSR has reached its bottom most position and to measure the drop time. Results of feasibility study on laboratory model have been reported earlier. Testing of a 1:1 scale engineering model of ECPS is reported in this paper. Results obtained from the high temperature sodium testing of ECPS indicate a clearly measurable change in pick up voltage with sensitivity of 11 % at 675 Hz. The ECPS is in advanced stage of implementation in DSRDM of PFBR. (authors)

  3. Plasma-based localized defect for switchable coupling applications

    SciTech Connect (OSTI)

    Varault, Stefan [ONERA/DEMR, 2, Avenue Edouard Belin, BP4025, 31055 Toulouse Cedex (France); LAboratoire PLAsma et Conversion d'Energie (LAPLACE), UPS, CNRS, 118 Route de Narbonne, F-31062 Toulouse Cedex 9 (France); Gabard, Benjamin [STAE, 4, rue Emile Monso, BP84234, 31030 Toulouse, Cedex 4 (France); Sokoloff, Jerome [LAboratoire PLAsma et Conversion d'Energie (LAPLACE), UPS, CNRS, 118 Route de Narbonne, F-31062 Toulouse Cedex 9 (France); Bolioli, Sylvain [ONERA/DEMR, 2, Avenue Edouard Belin, BP4025, 31055 Toulouse Cedex (France)

    2011-03-28T23:59:59.000Z

    We report in this paper experimental measurements in order to validate the concept of switchable electromagnetic band gap filters based on plasma capillaries in the microwave regime. The plasma tube is embedded inside the structure to create a bistable (plasma on or off) punctual defect. We first investigate two kinds of discharge tubes: Ar-Hg and pure Ne, which we then use to experimentally achieve plasma-based reconfigurable applications, namely, a two-port coupler and a two-port demultiplexer.

  4. CHAPTER 7. BERYLLIUM ANALYSIS BY NON-PLASMA BASED METHODS

    SciTech Connect (OSTI)

    Ekechukwu, A

    2009-04-20T23:59:59.000Z

    The most common method of analysis for beryllium is inductively coupled plasma atomic emission spectrometry (ICP-AES). This method, along with inductively coupled plasma mass spectrometry (ICP-MS), is discussed in Chapter 6. However, other methods exist and have been used for different applications. These methods include spectroscopic, chromatographic, colorimetric, and electrochemical. This chapter provides an overview of beryllium analysis methods other than plasma spectrometry (inductively coupled plasma atomic emission spectrometry or mass spectrometry). The basic methods, detection limits and interferences are described. Specific applications from the literature are also presented.

  5. Coupled microwave ECR and radio-frequency plasma source for plasma processing

    DOE Patents [OSTI]

    Tsai, C.C.; Haselton, H.H.

    1994-03-08T23:59:59.000Z

    In a dual plasma device, the first plasma is a microwave discharge having its own means of plasma initiation and control. The microwave discharge operates at electron cyclotron resonance (ECR), and generates a uniform plasma over a large area of about 1000 cm[sup 2] at low pressures below 0.1 mtorr. The ECR microwave plasma initiates the second plasma, a radio frequency (RF) plasma maintained between parallel plates. The ECR microwave plasma acts as a source of charged particles, supplying copious amounts of a desired charged excited species in uniform manner to the RF plasma. The parallel plate portion of the apparatus includes a magnetic filter with static magnetic field structure that aids the formation of ECR zones in the two plasma regions, and also assists in the RF plasma also operating at electron cyclotron resonance. 4 figures.

  6. Coupled microwave ECR and radio-frequency plasma source for plasma processing

    DOE Patents [OSTI]

    Tsai, Chin-Chi (Oak Ridge, TN); Haselton, Halsey H. (Knoxville, TN)

    1994-01-01T23:59:59.000Z

    In a dual plasma device, the first plasma is a microwave discharge having its own means of plasma initiation and control. The microwave discharge operates at electron cyclotron resonance (ECR), and generates a uniform plasma over a large area of about 1000 cm.sup.2 at low pressures below 0.1 mtorr. The ECR microwave plasma initiates the second plasma, a radio frequency (RF) plasma maintained between parallel plates. The ECR microwave plasma acts as a source of charged particles, supplying copious amounts of a desired charged excited species in uniform manner to the RF plasma. The parallel plate portion of the apparatus includes a magnetic filter with static magnetic field structure that aids the formation of ECR zones in the two plasma regions, and also assists in the RF plasma also operating at electron cyclotron resonance.

  7. A Coupled Approach for Plasma-Based Flow Control Simulations of Wing Sections

    E-Print Network [OSTI]

    Roy, Subrata

    a role in momentum coupling, though as noted in Ref. 10 there is no significant heating of the airA Coupled Approach for Plasma-Based Flow Control Simulations of Wing Sections Datta V. Gaitonde Vehicles Directorate Kettering University Air Force Research Laboratory Flint, MI 48504 Wright

  8. Under consideration for publication in J. Plasma Phys. 1 Flow dynamics and magnetic induction in

    E-Print Network [OSTI]

    .g. turbulence in thermonuclear fusion plasmas). Within the magnetohydrodynamic (MHD) frame of description

  9. Prolactin-stimulated ornithine decarboxylase induction in rat hepatocytes: Coupling to diacylglycerol generation and protein kinase C

    SciTech Connect (OSTI)

    Buckley, A.R.; Buckley, D.J. (Kirksville College of Osteopathic Medicine, MO (USA))

    1991-01-01T23:59:59.000Z

    The trophic effects of prolactin (PRL) in rat liver have been linked to activation of protein kinase C (PKC). Since alterations in PKC activity imply its activation by 1,2-diacylglycerol (DAG), we tested whether PRL treatment stimulated DAG generation coupled to induction of a growth response in primary hepatocytes. Addition of PRL to hepatocyte cultures significantly increased ({sup 3}H)-glycerol incorporation into DAG within 5 minutes which was followed by a loss of cytosolic PKC activity by 10 minutes. Prolactin also significantly enhanced radiolabel incorporation into triacylglycerol and phospholipids within 10 minutes and induced ODC activity at 6 hours. Therefore, prolactin-stimulated alterations in PKC activity are preceded by enhanced DAG generation. Moreover, these events appear to be coupled to PRL-stimulated entry of hepatocytes into cell cycle.

  10. Dynamic properties of one-component strongly coupled plasmas: The sum-rule approach

    SciTech Connect (OSTI)

    Arkhipov, Yu. V.; Askaruly, A.; Davletov, A. E. [Department of Optics and Plasma Physics, Al-Farabi Kazakh National University, Tole Bi 96, Almaty 050012 (Kazakhstan); Ballester, D. [School of Mathematics and Physics, Queen's University, Belfast BT7 1NN (United Kingdom); Tkachenko, I. M. [Instituto de Matematica Pura y Aplicada, Universidad Politecnica de Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Zwicknagel, G. [Institut fuer Theoretische Physik II, Erlangen-Nuernberg Universitaet, Staudtstr. 7, D-91058 Erlangen (Germany)

    2010-02-15T23:59:59.000Z

    The dynamic characteristics of strongly coupled one-component plasmas are studied within the moment approach. Our results on the dynamic structure factor and the dynamic local-field correction satisfy the sum rules and other exact relations automatically. A quantitative agreement is obtained with numerous simulation data on the plasma dynamic properties, including the dispersion and decay of collective modes. Our approach allows us to correct and complement the results previously found with other treatments.

  11. Selective killing of ovarian cancer cells through induction of apoptosis by nonequilibrium atmospheric pressure plasma

    SciTech Connect (OSTI)

    Iseki, Sachiko; Tanaka, Hiromasa; Kondo, Hiroki; Hori, Masaru [Department of Electrical Engineering and Computer Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Nakamura, Kae; Hayashi, Moemi; Kajiyama, Hiroaki; Kikkawa, Fumitaka [Department of Obstetrics and Gynecology, Nagoya University Graduate School of Medicine, Tsurumai-cho 65, Showa-ku, Nagoya 466-8550 (Japan); Kano, Hiroyuki [NU Eco-Engineering Co., Ltd., 1237-87 Umazutsumi, Kurozasa-cho, Miyoshi-shi, Nishikamo-gun, Aichi 470-0201 (Japan)

    2012-03-12T23:59:59.000Z

    Two independent ovarian cancer cell lines and fibroblast controls were treated with nonequilibrium atmospheric pressure plasma (NEAPP). Most ovarian cancer cells were detached from the culture dish by continuous plasma treatment to a single spot on the dish. Next, the plasma source was applied over the whole dish using a robot arm. In vitro cell proliferation assays showed that plasma treatments significantly decreased proliferation rates of ovarian cancer cells compared to fibroblast cells. Flow cytometry and western blot analysis showed that plasma treatment of ovarian cancer cells induced apoptosis. NEAPP could be a promising tool for therapy for ovarian cancers.

  12. Plasma effect in Silicon Charge Coupled Devices (CCDs)

    E-Print Network [OSTI]

    Juan Estrada; Jorge Molina; J. Blostein; G. Fernandez

    2011-05-28T23:59:59.000Z

    Plasma effect is observed in CCDs exposed to heavy ionizing alpha-particles with energies in the range 0.5 - 5.5 MeV. The results obtained for the size of the charge clusters reconstructed on the CCD pixels agrees with previous measurements in the high energy region (>3.5 MeV). The measurements were extended to lower energies using alpha-particles produced by (n,alpha) reactions of neutrons in a Boron-10 target. The effective linear charge density for the plasma column is measured as a function of energy. The results demonstrate the potential for high position resolution in the reconstruction of alpha particles, which opens an interesting possibility for using these detectors in neutron imaging applications.

  13. Visco-elastic fluid simulations of coherent structures in strongly coupled dusty plasma medium

    SciTech Connect (OSTI)

    Singh Dharodi, Vikram; Kumar Tiwari, Sanat; Das, Amita, E-mail: amita@ipr.res.in [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2014-07-15T23:59:59.000Z

    A generalized hydrodynamic model depicting the behaviour of visco-elastic fluids has often been invoked to explore the behaviour of a strongly coupled dusty plasma medium below their crystallization limit. The model has been successful in describing the collective normal modes of the strongly coupled dusty plasma medium observed experimentally. The paper focuses on the study of nonlinear dynamical characteristic features of this model. Specifically, the evolution of coherent vorticity patches is being investigated here within the framework of this model. A comparison with Newtonian fluids and molecular dynamics simulations treating the dust species interacting through the Yukawa potential has also been presented.

  14. Theoretical investigation of phase-controlled bias effect in capacitively coupled plasma discharges

    SciTech Connect (OSTI)

    Kwon, Deuk-Chul; Yoon, Jung-Sik [Convergence Plasma Research Center, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)

    2011-07-15T23:59:59.000Z

    We theoretically investigated the effect of phase difference between powered electrodes in capacitively coupled plasma (CCP) discharges. Previous experimental result has shown that the plasma potential could be controlled by using a phase-shift controller in CCP discharges. In this work, based on the previously developed radio frequency sheath models, we developed a circuit model to self-consistently determine the bias voltage from the plasma parameters. Results show that the present theoretical model explains the experimental results quite well and there is an optimum value of the phase difference for which the V{sub dc}/V{sub pp} ratio becomes a minimum.

  15. Effect of running coupling on photon emission from quark gluon plasma

    E-Print Network [OSTI]

    Mahatsab Mandal; Sukanya Mitra; Pradip Roy; Sourav Sarkar

    2012-06-22T23:59:59.000Z

    We discuss the role of running coupling on the thermal photon yield from quark gluon plasma. It is shown that the photon production rate from the partonic phase is considerably enhanced when running coupling is considered with respect to a fixed value. However, we show by explicit evaluation that although this difference survives the space-time evolution the experimental data cannot distinguish between the two once the hard contribution, which is an essential component of photon production mechanism, is added.

  16. Influence of finite geometrical asymmetry of the electrodes in capacitively coupled radio frequency plasma

    SciTech Connect (OSTI)

    Bora, B., E-mail: bbora@cchen.cl; Soto, L. [Comisión Chilena de Energía Nuclear, Santiago, Chile and Center for Research and Applications in Plasma Physics and Pulsed Power, P4 (Chile)

    2014-08-15T23:59:59.000Z

    Capacitively coupled radio frequency (CCRF) plasmas are widely studied in last decades due to the versatile applicability of energetic ions, chemically active species, radicals, and also energetic neutral species in many material processing fields including microelectronics, aerospace, and biology. A dc self-bias is known to generate naturally in geometrically asymmetric CCRF plasma because of the difference in electrode sizes known as geometrical asymmetry of the electrodes in order to compensate electron and ion flux to each electrode within one rf period. The plasma series resonance effect is also come into play due to the geometrical asymmetry and excited several harmonics of the fundamental in low pressure CCRF plasma. In this work, a 13.56?MHz CCRF plasma is studied on the based on the nonlinear global model of asymmetric CCRF discharge to understand the influences of finite geometrical asymmetry of the electrodes in terms of generation of dc self-bias and plasma heating. The nonlinear global model on asymmetric discharge has been modified by considering the sheath at the grounded electrode to taking account the finite geometrical asymmetry of the electrodes. The ion density inside both the sheaths has been taken into account by incorporating the steady-state fluid equations for ions considering that the applied rf frequency is higher than the typical ion plasma frequency. Details results on the influences of geometrical asymmetry on the generation of dc self-bias and plasma heating are discussed.

  17. 450 mm dual frequency capacitively coupled plasma sources: Conventional, graded, and segmented electrodes

    E-Print Network [OSTI]

    Kushner, Mark

    450 mm dual frequency capacitively coupled plasma sources: Conventional, graded, and segmented fabrication will soon transition from 300 to 450 mm at a time when excitation frequencies for capacitively of processing. The increase in diameter to 450 mm is likely to exacerbate these effects, perhaps requiring

  18. Recent Advances in the SPIRIT (Self-organized Plasma with Induction, Reconnection, and Injection Techniques)

    E-Print Network [OSTI]

    Ji, Hantao

    for favorable energetic balance. In response to the demands in all these four areas, a new concept called Self the plasma shape and kinetic parameter, by using passive stabilizers, and by injecting energetic ions; (3 been obtained in MRX. New numerical simulations showed that FRC plasmas can be globally stabilized

  19. Ab-initio calculations on two-electron ions in strongly coupled plasma environment

    E-Print Network [OSTI]

    Bhattacharyya, S; Mukherjee, T K

    2015-01-01T23:59:59.000Z

    In this work, the controversy between the interpretations of recent measurements on dense aluminum plasma created with Linac coherent light sources (LCLS) X-ray free electron laser (FEL) and Orion laser has been addressed. In both kind of experiments, helium-like and hydrogen-like spectral lines are used for plasma diagnostics . However, there exist no precise theoretical calculations for He-like ions within dense plasma environment. The strong need for an accurate theoretical estimates for spectral properties of He-like ions in strongly coupled plasma environment leads us to perform ab initio calculations in the framework of Rayleigh-Ritz variation principle in Hylleraas coordinates where ion-sphere potential is used. An approach to resolve the long-drawn problem of numerical instability for evaluating two-electron integrals with extended basis inside a finite domain is presented here. The present values of electron densities corresponding to disappearance of different spectral lines obtained within the fram...

  20. Large area radio frequency plasma for microelectronics processing Z. Yu and D. Shaw

    E-Print Network [OSTI]

    Collins, George J.

    focus on wide area plasma uniformity and undesired antenna window erosion caused by the plasma. OurLarge area radio frequency plasma for microelectronics processing Z. Yu and D. Shaw Colorado State November 1994 Radio-frequency rf inductively coupled planar plasma ICP provides a better way to generate

  1. Coupling highly excited nuclei to the atomic shell in dense astrophysical plasmas

    E-Print Network [OSTI]

    Stephan Helmrich; Katja Spenneberg; Adriana Pálffy

    2014-07-25T23:59:59.000Z

    In dense astrophysical plasmas, neutron capture populates highly excited nuclear states close to the neutron threshold. The impact of additional low-energy nuclear excitations via coupling to the atomic shell on the ability of the so-formed compound nucleus to retain the captured neutron is investigated. We focus on the mechanism of nuclear excitation by electron capture in plasmas characterized by electron fluxes typical for the slow neutron capture process of stellar nucleosynthesis. The small effect of this further excitation on the neutron capture and gamma decay sequence relevant for nucleosynthesis is quantified and compared to the corresponding effect of an additional low-energy photoexcitation step.

  2. Apparatus and method for reducing inductive coupling between levitation and drive coils within a magnetic propulsion system

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    2001-01-01T23:59:59.000Z

    An apparatus and method is disclosed for reducing inductive coupling between levitation and drive coils within a magnetic levitation system. A pole array has a magnetic field. A levitation coil is positioned so that in response to motion of the magnetic field of the pole array a current is induced in the levitation coil. A first drive coil having a magnetic field coupled to drive the pole array also has a magnetic flux which induces a parasitic current in the levitation coil. A second drive coil having a magnetic field is positioned to attenuate the parasitic current in the levitation coil by canceling the magnetic flux of the first drive coil which induces the parasitic current. Steps in the method include generating a magnetic field with a pole array for levitating an object; inducing current in a levitation coil in response to motion of the magnetic field of the pole array; generating a magnetic field with a first drive coil for propelling the object; and generating a magnetic field with a second drive coil for attenuating effects of the magnetic field of the first drive coil on the current in the levitation coil.

  3. REPORT OF THE INDUCTIVELY COUPLED PLASMA -MASS SPECTROMETRY (ICP-MS)

    E-Print Network [OSTI]

    Three year Full Service Contract 1 CETAC Ultrasonic Nebulization Unit (Fig. 6) 1 Consumables Package 1

  4. THE NOTRE DAME INDUCTIVELY COUPLED PLASMA -MASS SPECTROMETRY (ICP-MS)

    E-Print Network [OSTI]

    the PQII STE ICP-MS, Electrothermal Vaporization, and Laser Ablation units The report supercedes STE, LaserProbe (tuned to 266 nm, but with 532 nm and 1046 nm capabilities), CETAC Ultrasonic

  5. Representative sampling using single-pulse laser ablation with inductively coupled plasma mass spectroscopy

    E-Print Network [OSTI]

    Liu, Haichen; Mao, Xianglei; Russo, Richard E.

    2001-01-01T23:59:59.000Z

    U also achieved a representative value at high irradiance.Representative sampling using single-pulse laser ablationvalue close to the representative level. Segregation during

  6. Sound waves in strongly coupled non-conformal gauge theory plasma

    E-Print Network [OSTI]

    Paolo Benincasa; Alex Buchel; Andrei O. Starinets

    2005-11-10T23:59:59.000Z

    Using gauge theory/gravity duality we study sound wave propagation in strongly coupled non-conformal gauge theory plasma. We compute the speed of sound and the bulk viscosity of N=2^* supersymmetric SU(N_c) Yang-Mills plasma at a temperature much larger than the mass scale of the theory in the limit of large N_c and large 't Hooft coupling. The speed of sound is computed both from the equation of state and the hydrodynamic pole in the stress-energy tensor two-point correlation function. Both computations lead to the same result. Bulk viscosity is determined by computing the attenuation constant of the sound wave mode.

  7. Simple thermodynamics of strongly coupled one-component-plasma in two and three dimensions

    SciTech Connect (OSTI)

    Khrapak, Sergey A., E-mail: Sergey.Khrapak@dlr.de [Forschungsgruppe Komplexe Plasmen, Deutsches Zentrum für Luft- und Raumfahrt, Oberpfaffenhofen (Germany); Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation); Khrapak, Alexey G. [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation)

    2014-10-15T23:59:59.000Z

    Simple analytical approximations for the internal energy of the strongly coupled one-component-plasma in two and three dimensions are discussed. As a result, new practical expressions for the internal energy in the fluid phase are proposed. Their accuracy is checked by evaluating the location of the fluid-solid phase transition from the free energy consideration. Possible applications to other related systems are briefly discussed.

  8. Positron impact excitations of hydrogen atom embedded in weakly coupled plasmas: Formation of Rydberg atoms

    SciTech Connect (OSTI)

    Rej, Pramit; Ghoshal, Arijit, E-mail: aghoshal@math.buruniv.ac.in [Department of Mathematics, Burdwan University, Golapbag, Burdwan 713 104, West Bengal (India)

    2014-09-15T23:59:59.000Z

    Formation of Rydberg atoms due to 1s?nlm excitations of hydrogen, for arbitrary n, l, m, by positron impact in weakly coupled plasma has been investigated using a distorted-wave theory in the momentum space. The interactions among the charged particles in the plasma have been represented by Debye-Huckel potentials. Making use of a simple variationally determined wave function for the hydrogen atom, it has been possible to obtain the distorted-wave scattering amplitude in a closed analytical form. A detailed study has been made on the effects of plasma screening on the differential and total cross sections in the energy range 20–300?eV of incident positron. For the unscreened case, our results agree nicely with some of the most accurate results available in the literature. To the best of our knowledge, such a study on the differential and total cross sections for 1s?nlm inelastic positron-hydrogen collisions for arbitrary n, l, m in weakly coupled plasmas is the first reported in the literature.

  9. The Integrated Plasma Simulator: A Flexible Python Framework for Coupled Multiphysics Simulation

    SciTech Connect (OSTI)

    Foley, Samantha S [ORNL; Elwasif, Wael R [ORNL; Bernholdt, David E [ORNL

    2011-11-01T23:59:59.000Z

    High-fidelity coupled multiphysics simulations are an increasingly important aspect of computational science. In many domains, however, there has been very limited experience with simulations of this sort, therefore research in coupled multiphysics often requires computational frameworks with significant flexibility to respond to the changing directions of the physics and mathematics. This paper presents the Integrated Plasma Simulator (IPS), a framework designed for loosely coupled simulations of fusion plasmas. The IPS provides users with a simple component architecture into which a wide range of existing plasma physics codes can be inserted as components. Simulations can take advantage of multiple levels of parallelism supported in the IPS, and can be controlled by a high-level ``driver'' component, or by other coordination mechanisms, such as an asynchronous event service. We describe the requirements and design of the framework, and how they were implemented in the Python language. We also illustrate the flexibility of the framework by providing examples of different types of simulations that utilize various features of the IPS.

  10. Dynamics of compressional Mach cones in a strongly coupled complex plasma

    SciTech Connect (OSTI)

    Bandyopadhyay, P., E-mail: pintu@ipr.res.in; Dey, R.; Sen, Abhijit [Institute for Plasma Research, Bhat, Gandhinagar-382428 (India); Kadyan, Sangeeta [Department of Physics, Maharshi Dayanand University, Rohtak 124001 (India)

    2014-10-15T23:59:59.000Z

    Using a Generalised-Hydrodynamic (GH) fluid model, we study the influence of strong coupling induced modification of the fluid compressibility on the dynamics of compressional Mach cones in a dusty plasma medium. A significant structural change of lateral wakes for a given Mach number and Epstein drag force is found in the strongly coupled regime. With the increase of fluid compressibility, the peak amplitude of the normalised perturbed dust density first increases and then decreases monotonically after reaching its maximum value. It is also noticed that the opening angle of the cone structure decreases with the increase of the compressibility of the medium and the arm of the Mach cone breaks up into small structures in the velocity vector profile when the coupling between the dust particles increases.

  11. Theoretical study of head-on collision of dust acoustic solitary waves in a strongly coupled complex plasma

    SciTech Connect (OSTI)

    Jaiswal, S., E-mail: surabhi@ipr.res.in; Bandyopadhyay, P.; Sen, A. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

    2014-05-15T23:59:59.000Z

    We investigate the propagation characteristics of two counter propagating dust acoustic solitary waves (DASWs) undergoing a head-on collision, in the presence of strong coupling between micron sized charged dust particles in a complex plasma. A coupled set of nonlinear dynamical equations describing the evolution of the two DASWs using the extended Poincaré-Lighthill-Kuo perturbation technique is derived. The nature and extent of post collision phase-shifts of these solitary waves are studied over a wide range of dusty plasma parameters in a strongly and a weakly coupled medium. We find a significant change in the nature and amount of phase delay in the strongly coupled regime as compared to a weakly coupled regime. The phase shift is seen to change its sign beyond a threshold value of compressibility of the medium for a given set of dusty plasma parameters.

  12. Thermal plasma process for recovering monomers and high value carbons from polymeric materials

    DOE Patents [OSTI]

    Knight, Richard (Philadelphia, PA); Grossmann, Elihu D. (Narberth, PA); Guddeti, Ravikishan R. (Philadelphia, PA)

    2002-01-01T23:59:59.000Z

    The present invention relates to a method of recycling polymeric waste products into monomers and high value forms of carbon by pyrolytic conversion using an induction coupled RF plasma heated reactor.

  13. 450 mm dual frequency capacitively coupled plasma sources: Conventional, graded, and segmented electrodes

    SciTech Connect (OSTI)

    Yang Yang [Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States); Kushner, Mark J. [Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, Michigan 48109-2122 (United States)

    2010-12-01T23:59:59.000Z

    Wafer diameters for microelectronics fabrication will soon transition from 300 to 450 mm at a time when excitation frequencies for capacitively coupled plasmas (CCPs) are increasing to 200 MHz or higher. Already for 300 mm tools, there is evidence that wave behavior (i.e., propagation, constructive, and destructive interference) affects the uniformity of processing. The increase in diameter to 450 mm is likely to exacerbate these effects, perhaps requiring nontraditional tool designs. This is particularly important in dual frequency (DF) CCP tools in which there are potential interactions between frequencies. In this paper, results from a two-dimensional computational investigation of Ar plasma properties in a 450 mm DF-CCP reactor, incorporating a full-wave solution of Maxwell's equations, are discussed. As in 300 mm DF-CCP reactors, the electron density collapses toward the center of the reactor with increasing high frequency (HF), however, with more pronounced finite wavelength effects. Graded conductivity electrodes with multilayer of dielectrics are computationally demonstrated as a possible means to suppress wave effects thereby increasing plasma uniformity. Segmentation of the HF electrode also improves the plasma uniformity by making the electrical distance between the feeds and the sheath edges as uniform as possible.

  14. Obliquely propagating waves in the magnetized strongly coupled one-component plasma

    SciTech Connect (OSTI)

    Kählert, Hanno; Kalman, Gabor J. [Department of Physics, Boston College, 140 Commonwealth Ave, Chestnut Hill, Massachusetts 02467 (United States)] [Department of Physics, Boston College, 140 Commonwealth Ave, Chestnut Hill, Massachusetts 02467 (United States); Ott, Torben; Bonitz, Michael [Institut für Theoretische Physik und Astrophysik, Christian-Albrechts Universität zu Kiel, Leibnizstr. 15, 24098 Kiel (Germany)] [Institut für Theoretische Physik und Astrophysik, Christian-Albrechts Universität zu Kiel, Leibnizstr. 15, 24098 Kiel (Germany); Reynolds, Alexi [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)] [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2013-05-15T23:59:59.000Z

    The quasi-localized charge approximation is used to calculate the wave spectrum of the magnetized three-dimensional strongly coupled one-component plasma at arbitrary angles ? between the wave vector and the magnetic field axis. Three frequency branches are identified whose interplay is strongly determined by ?=?{sub c}/?{sub p}, the ratio of the cyclotron frequency ?{sub c}, and the plasma frequency ?{sub p}. The frequency dispersion relations for the three principal modes along the magnetic field cross in the case ?<1, which strongly affects the transition from parallel to perpendicular wave propagation. For ?>1, the frequencies of the different branches are well separated, and the long-wavelength dispersion in the intermediate and upper branch changes sign as ? is varied from 0 to ?/2. In addition to the frequencies, we also investigate the waves' polarization properties.

  15. VOLUME 78, NUMBER 8 P H Y S I C A L R E V I E W L E T T E R S 24 FEBRUARY 1997 Debye Shielding and Particle Correlations in Strongly Coupled Dusty Plasmas

    E-Print Network [OSTI]

    Otani, Niels F.

    in dusty plasma research, while fully aware that the dust particles are strongly coupled, have continued

  16. MICROCAVITYMICROCAVITY PLASMA SCIENCE AND RECENTPLASMA SCIENCE AND RECENT APPLICATIONS: BOUNDAPPLICATIONS: BOUND--FREE COUPLING, TRANSISTORFREE COUPLING, TRANSISTOR

    E-Print Network [OSTI]

    Shyy, Wei

    Electrode Glass6 mm 250 m LED Backlight Microcavity Lamp #12;OPERATION OF MICROCAVITY PLASMA DEVICES Plasma Surface Treatment High Intensity Plasma Arc Lamp Spark Gap Plasma Display (150 inch Panasonic ) Ozone generator Fluorescent Lamp Gas Laser #12;University of Illinois Laboratory for Optical Physics

  17. Self-excited nonlinear plasma series resonance oscillations in geometrically symmetric capacitively coupled radio frequency discharges

    SciTech Connect (OSTI)

    Donko, Z. [Research Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Schulze, J.; Czarnetzki, U.; Luggenhoelscher, D. [Institute for Plasma and Atomic Physics, Ruhr-University Bochum, Bochum 44780 (Germany)

    2009-03-30T23:59:59.000Z

    At low pressures, nonlinear self-excited plasma series resonance (PSR) oscillations are known to drastically enhance electron heating in geometrically asymmetric capacitively coupled radio frequency discharges by nonlinear electron resonance heating (NERH). Here we demonstrate via particle-in-cell simulations that high-frequency PSR oscillations can also be excited in geometrically symmetric discharges if the driving voltage waveform makes the discharge electrically asymmetric. This can be achieved by a dual-frequency (f+2f) excitation, when PSR oscillations and NERH are turned on and off depending on the electrical discharge asymmetry, controlled by the phase difference of the driving frequencies.

  18. Kelvin-Helmholtz instability in a strongly coupled dusty plasma medium

    SciTech Connect (OSTI)

    Tiwari, Sanat Kumar; Das, Amita; Patel, Bhavesh G. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Angom, Dilip [Physical Research Laboratory, Ahmedabad 380 009 (India); Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Physical Research Laboratory, Ahmedabad 380 009 (India)

    2012-07-15T23:59:59.000Z

    The Kelvin-Helmholtz (KH) instability in the context of strongly coupled dusty plasma medium has been investigated. In particular, the role of transverse shear and the compressional acoustic modes in both the linear and nonlinear regimes of the KH instability has been studied. It is observed that in addition to the conventional nonlocal KH instability, there exists a local instability in the strong coupling case. The interplay of the KH mode with this local instability shows up in the simulations as an interesting phenomenon of recurrence in the nonlinear regime. Thus, a cyclic KH instability process is observed to occur. These cyclic events are associated with bursts of activity in terms of transverse and compressional wave generation in the medium.

  19. Controller design issues in the feedback control of radio frequency plasma processing reactors

    E-Print Network [OSTI]

    Kushner, Mark

    Controller design issues in the feedback control of radio frequency plasma processing reactors feedback control of inductively coupled plasma processing reactors for polysilicon etching and be successfully used for feedback control of plasma processing reactors.4 There are many control strate- gies

  20. Head-on collision of dust-acoustic shock waves in strongly coupled dusty plasmas

    SciTech Connect (OSTI)

    EL-Shamy, E. F., E-mail: emadel-shamy@hotmail.com [Department of physics, Faculty of Science, Damietta University, New Damietta 34517 (Egypt); Department of Physics, College of Science, King Khalid University, P.O. 9004, Abha (Saudi Arabia); Al-Asbali, A. M., E-mail: aliaa-ma@hotmail.com [Department of Physics, College of Science for Girls in Abha, King Khalid University, Abha, P.O. 960 (Saudi Arabia)

    2014-09-15T23:59:59.000Z

    A theoretical investigation is carried out to study the propagation and the head-on collision of dust-acoustic (DA) shock waves in a strongly coupled dusty plasma consisting of negative dust fluid, Maxwellian distributed electrons and ions. Applying the extended Poincaré–Lighthill–Kuo method, a couple of Korteweg–deVries–Burgers equations for describing DA shock waves are derived. This study is a first attempt to deduce the analytical phase shifts of DA shock waves after collision. The impacts of physical parameters such as the kinematic viscosity, the unperturbed electron-to-dust density ratio, parameter determining the effect of polarization force, the ion-to-electron temperature ratio, and the effective dust temperature-to-ion temperature ratio on the structure and the collision of DA shock waves are examined. In addition, the results reveal the increase of the strength and the steepness of DA shock waves as the above mentioned parameters increase, which in turn leads to the increase of the phase shifts of DA shock waves after collision. The present model may be useful to describe the structure and the collision of DA shock waves in space and laboratory dusty plasmas.

  1. Coupled ion acoustic and drift waves in magnetized superthermal electron-positron-ion plasmas

    SciTech Connect (OSTI)

    Adnan, Muhammad; Qamar, Anisa [Institute of Physics and Electronics, University of Peshawar, Peshawar 25000 (Pakistan); National Center for Physics, Quaid-i-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Mahmood, S. [National Center for Physics, Quaid-i-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Theoretical Physics Division, PINSTECH P.O. Nilore Islamabad 44000 (Pakistan); Physics Institute, Federal University of Rio Grande do Sul (UFRGS), 915051-970, Porto Alegre, RS (Brazil)

    2014-09-15T23:59:59.000Z

    Linear and nonlinear coupled drift-ion acoustic waves are investigated in a nonuniform magnetoplasma having kappa distributed electrons and positrons. In the linear regime, the role of kappa distribution and positron content on the dispersion relation has been highlighted; it is found that strong superthermality (low value of ?) and addition of positrons lowers the phase velocity via decreasing the fundamental scalelengths of the plasmas. In the nonlinear regime, first, coherent nonlinear structure in the form of dipoles and monopoles are obtained and the boundary conditions (boundedness) in the context of superthermality and positron concentrations are discussed. Second, in case of scalar nonlinearity, a Korteweg–de Vries-type equation is obtained, which admit solitary wave solution. It is found that both compressive and rarefactive solitons are formed in the present model. The present work may be useful to understand the low frequency electrostatic modes in inhomogeneous electron positron ion plasmas, which exist in astrophysical plasma situations such as those found in the pulsar magnetosphere.

  2. Multi-chord fiber-coupled interferometry of supersonic plasma jets andcomparisons with synthetic data

    SciTech Connect (OSTI)

    Merritt, Elizabeth C. [Los Alamos National Laboratory; Lynn, Alan G. [Los Alamos National Laboratory; Gilmore, Mark A. [Los Alamos National Laboratory; Thoma, Carsten [Voss Scientific LLC; Loverich, John [Tech-X Corporation; Hsu, Scott C. [Los Alamos National Laboratory

    2012-05-03T23:59:59.000Z

    A multi-chord fiber-coupled interferometer [Merritt et al., Rev. Sci. Instrum. 83, 033506 (2012)] is being used to make time-resolved density measurements of supersonic argon plasma jets on the Plasma Liner Experiment [Hsu et al., Bull. Amer. Phys. Soc. 56, 307 (2011)]. The long coherence length of the laser (> 10 m) allows signal and reference path lengths to be mismatched by many meters without signal degradation, making for a greatly simplified optical layout. Measured interferometry phase shifts are consistent with a partially ionized plasma in which an initially positive phase shift becomes negative when the ionization fraction drops below a certain threshold. In this case, both free electrons and bound electrons in ions and neutral atoms contribute to the index of refraction. This paper illustrates how the interferometry data, aided by numerical modeling, are used to derive total jet density, jet propagation velocity ({approx} 15-50 km/s), jet length ({approx} 20-100 cm), and 3D expansion.

  3. Analysis and design of resonant inductively coupled circuits : application to benefit denial solutions for the retail industry

    E-Print Network [OSTI]

    Rony, Amaury

    2013-01-01T23:59:59.000Z

    ProTeqt develops benefit denial solutions that are electromagnetically deactivated. A magnetic field from the deactivation tablet inductively heats an enabler that provides the proper force to disengage the locking mechanism. ...

  4. Effects of the Running of the QCD Coupling on the Energy Loss in the Quark-Gluon Plasma

    E-Print Network [OSTI]

    Jens Braun; Hans-Jürgen Pirner

    2006-10-25T23:59:59.000Z

    Finite temperature modifies the running of the QCD coupling alpha_s(k,T) with resolution k. After calculating the thermal quark and gluon masses selfconsistently, we determine the quark-quark and quark-gluon cross sections in the plasma based on the running coupling. We find that the running coupling enhances these cross sections by factors of two to four depending on the temperature. We also compute the energy loss dE/dx of a high-energy quark in the plasma as a function of temperature. Our study suggests that, beside t-channel processes, inverse Compton scattering is a relevant process for a quantitative understanding of the energy loss of an incident quark in a hot plasma.

  5. Effects of the running of the QCD coupling on the energy loss in the quark-gluon plasma

    SciTech Connect (OSTI)

    Braun, Jens [Institute for Theoretical Physics, University of Heidelberg, Philosophenweg 19, 69120 Heidelberg (Germany); Pirner, Hans-Juergen [Institute for Theoretical Physics, University of Heidelberg, Philosophenweg 19, 69120 Heidelberg (Germany); Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany)

    2007-03-01T23:59:59.000Z

    Finite temperature modifies the running of the QCD coupling {alpha}{sub s}(k,T) with resolution k. After calculating the thermal quark and gluon masses self-consistently, we determine the quark-quark and quark-gluon cross sections in the plasma based on the running coupling. We find that the running coupling enhances these cross sections by factors of two to four depending on the temperature. We also compute the energy loss (dE/dx) of a high-energy quark in the plasma as a function of temperature. Our study suggests that, beside t-channel processes, inverse Compton scattering is a relevant process for a quantitative understanding of the energy loss of an incident quark in a hot plasma.

  6. Doubly fed induction machine

    DOE Patents [OSTI]

    Skeist, S. Merrill; Baker, Richard H.

    2005-10-11T23:59:59.000Z

    An electro-mechanical energy conversion system coupled between an energy source and an energy load including an energy converter device having a doubly fed induction machine coupled between the energy source and the energy load to convert the energy from the energy source and to transfer the converted energy to the energy load and an energy transfer multiplexer coupled to the energy converter device to control the flow of power or energy through the doubly fed induction machine.

  7. Dynamics of the longitudinal and transverse modes in presence of equilibrium shear flow in a strongly coupled dusty plasma

    SciTech Connect (OSTI)

    Garai, S.; Banerjee, D.; Janaki, M. S.; Chakrabarti, N. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata - 700 064 (India)

    2014-02-11T23:59:59.000Z

    In strongly coupled limit the general hydrodynamic (GH) model shows that the dusty plasma, acquiring significant rigidity, is able to support the 'shear' like mode [P. K. Kaw and A. Sen, Phys. Plasmas 5, 3552 (1998)]. In presence of velocity shear, this shear like mode is coupled with the dust acoustic mode which is generated by the compressibility effect of the dust fluid due to the finite temperature of the dust, electron and ion fluids. Local dispersion shows the velocity shear is also responsible for the instabilities of the shear mode, acoustic mode, as well as the shear-acoustic coupled mode. The present work, carried out in GH visco-elastic formalism, also gives the clear insight of the instabilities of the coupled mode in non local regime with a hyperbolic tangent velocity shear profile over a finite width.

  8. Sound waves in strongly coupled non-conformal gauge theory plasma

    E-Print Network [OSTI]

    Paolo Benincasa

    2005-07-04T23:59:59.000Z

    Gauge/string correspondence provides an efficient method to investigate gauge theories. In this talk we discuss the results of the paper (to appear) by P. Benincasa, A. Buchel and A. O. Starinets, where the propagation of sound waves is studied in a strongly coupled non-conformal gauge theory plasma. In particular, a prediction for the speed of sound as well as for the bulk viscosity is made for the N=2* gauge theory in the high temperature limit. As expected, the results achieved show a deviation from the speed of sound and the bulk viscosity for a conformal theory. It is pointed out that such results depend on the particular gauge theory considered.

  9. Drag and jet quenching of heavy quarks in a strongly coupled N=2* plasma

    E-Print Network [OSTI]

    Carlos Hoyos-Badajoz

    2009-09-14T23:59:59.000Z

    The drag of a heavy quark and the jet quenching parameter are studied in the strongly coupled N=2* plasma using the AdS/CFT correspondence. Both increase in units of the spatial string tension as the theory departs from conformal invariance. The description of heavy quark dynamics using a Langevin equation is also considered. It is found that the difference between the velocity dependent factors of the transverse and longitudinal momentum broadening of the quark admit an interpretation in terms of relativistic effects, so the distribution is spherical in the quark rest frame. When conformal invariance is broken there is a broadening of the longitudinal momentum distribution. This effect may be useful in understanding the jet distribution observed in experiments.

  10. Head-on-collision of modulated dust acoustic waves in strongly coupled dusty plasma

    SciTech Connect (OSTI)

    El-Labany, S. K.; El-Depsy, A.; Zedan, N. A. [Department of Physics, Faculty of Science, Damietta University, P.O. 34517, New Damietta (Egypt); El-Taibany, W. F. [Department of Physics, Faculty of Science, Damietta University, P.O. 34517, New Damietta (Egypt); Department of Physics, College of Science for Girls in Abha, King Khalid University, P.O. 960, Abha (Saudi Arabia); El-Shamy, E. F. [Department of Physics, Faculty of Science, Damietta University, P.O. 34517, New Damietta (Egypt); Department of Physics, College of Science, King Khalid University, P.O. 9004, Abha (Saudi Arabia)

    2012-10-15T23:59:59.000Z

    The derivative expansion perturbation method is applied to a strongly coupled dusty plasma system consisting of negatively charged dust grains, electrons, and ions. The basic equations are reduced to a nonlinear Schroedinger type equation appropriate for describing the modulated dust acoustic (DA) waves. We have examined the modulation (in) stability and the dependence of the system physical parameters (angular frequency and group velocity) on the polarization force variation. Finally, the extended Poincare-Lighthill-Kuo technique is employed to investigate the head-on collision (HoC) between two DA dark solitons. The analytical phase shifts and the trajectories of these dark solitons after the collision are derived. The numerical illustrations show that the polarization effect has strong influence on the nature of the phase shifts and the trajectories of the two DA dark solitons after collision.

  11. Effect of running coupling on photons from jet - plasma interaction in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Lusaka Bhattacharya; Pradip Roy

    2011-01-20T23:59:59.000Z

    We discuss the role of collisional energy loss on high $p_T$ photon data measured by PHENIX collaboration by calculating photon yield in jet-plasma interaction. The phase space distribution of the participating jet is dynamically evolved by solving Fokker-Planck equation. We treat the strong coupling constant ($\\alpha_s$) as function of momentum and temperature while calculating the drag and diffusion coefficients. It is observed that the quenching factor is substantially modified as compared to the case when $\\alpha_s$ is taken as constant. It is shown that the data is reasonably well reproduced when contributions from all the relevant sources are taken into account. Predictions at higher beam energies relevant for LHC experiment have been made.

  12. N-body Lyapunov expansion rates in one component strongly coupled plasmas

    SciTech Connect (OSTI)

    Ueshima, Y.; Nishihara, K.; Barnett, D.M.; Tajima, T.; Furukawa, H. [Institute of Laser Engineering, Osaka University, Suita, Osaka 565 (Japan)

    1996-05-01T23:59:59.000Z

    Phase space Lyapunov expansion rates are measured for the first time for Coulomb many body systems with the use of a 3-{ital d} particle code. The time averaged Lyapunov exponents, {lambda}/{omega}{sub {ital p}}, are found to be proportional to {Gamma}{sup {minus}2/5} and the cubic root of the diffusion coefficient in the range of 1{lt}{Gamma}{lt}160, where {omega}{sub {ital p}} and {Gamma} are plasma frequency and ion coupling constant, respectively. A large jump of the averaged Lyapunov exponent is observed near {Gamma}{approximately}170, corresponding to the phase transition from liquid to solid. Instantaneous Lyapunov exponent has chaotic behavior and consists of three different spectra, flat, {ital f}{sup {minus}2} and {ital f}{sup {minus}1}. {copyright} {ital 1996 American Institute of Physics.}

  13. The nonlinear coupling between gyroradius scale turbulence and mesoscale magnetic islands in fusion plasmas

    SciTech Connect (OSTI)

    Hornsby, W. A.; Peeters, A. G.; Snodin, A. P.; Casson, F. J.; Camenen, Y.; Szepesi, G. [Department of Physics, Centre for Fusion, Space, and Astrophysics, University of Warwick, Coventry (United Kingdom); Siccinio, M.; Poli, E. [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching bei Muenchen (Germany)

    2010-09-15T23:59:59.000Z

    The interaction between small scale turbulence (of the order of the ion Larmor radius) and mesoscale magnetic islands is investigated within the gyrokinetic framework. Turbulence, driven by background temperature and density gradients, over nonlinear mode coupling, pumps energy into long wavelength modes, and can result in an electrostatic vortex mode that coincides with the magnetic island. The strength of the vortex is strongly enhanced by the modified plasma flow response connected with the change in topology, and the transport it generates can compete with the parallel motion along the perturbed magnetic field. Despite the stabilizing effect of sheared plasma flows in and around the island, the net effect of the island is a degradation of the confinement. When density and temperature gradients inside the island are below the threshold for turbulence generation, turbulent fluctuations still persist through turbulence convection and spreading. The latter mechanisms then generate a finite transport flux and, consequently, a finite pressure gradient in the island. A finite radial temperature gradient inside the island is also shown to persist due to the trapped particles, which do not move along the field around the island. In the low collisionality regime, the finite gradient in the trapped population leads to the generation of a bootstrap current, which reduces the neoclassical drive.

  14. Particle simulation of Lyapunov exponents in one-component strongly coupled plasmas

    SciTech Connect (OSTI)

    Ueshima, Y.; Nishihara, K. [Institute of Laser Engineering, Osaka University, Suita, Osaka 565 (Japan)] [Institute of Laser Engineering, Osaka University, Suita, Osaka 565 (Japan); Barnett, D.M.; Tajima, T. [Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)] [Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States); Furukawa, H. [Institute for Laser Technology, Suita, Osaka 565 (Japan)] [Institute for Laser Technology, Suita, Osaka 565 (Japan)

    1997-03-01T23:59:59.000Z

    The Lyapunov exponents and instantaneous expansion rates in a phase space of Coulomb many-body systems are measured with the use of a three-dimensional particle code SCOPE [K. Nishihara, Kakuyugo Kenkyu {bold 66}, 253 (1991)]. The code calculates particle dynamics determined by Coulomb forces among individual particles. The Lyapunov exponents normalized by plasma frequency are found to be proportional to {Gamma}{sup {minus}2/5} in the range of 1{le}{Gamma}{le}160, where {Gamma} is the Coulomb coupling constant of the ion one-component plasma. There is a large jump of the Lyapunov exponent near {Gamma}{approximately}170, which corresponds to the phase transition from the liquid to the solid state in the one-component plasma. In the solid state, the normalized Lyapunov exponents are proportional to {Gamma}{sup {minus}6/5} for 170{lt}{Gamma}{lt}300. The observed dependence is discussed in analogy to a rigid-body particle system and a weakly nonlinear lattice system for liquid and solid states, respectively. Diffusion coefficients are found to be proportional to the third power of the Lyapunov exponent in the liquid state, that is, for 1{le}{Gamma}{le}160. These results imply that the Lyapunov exponent is in close relation to the transport processes. The instantaneous expansion rate starts from a small value and increases rapidly to a large peak value before declining slowly towards an asymptotic value. This stage is called the Lyapunov transient stage. Products of the transient time and the Lyapunov exponent are found to be 1.5{endash}2. Information of the initial state is lost after the transient time. The chaotic behavior of the instantaneous expansion rate is also shown. {copyright} {ital 1997} {ital The American Physical Society}

  15. Reduction of plasma density in the Helicity Injected Torus with Steady Inductance experiment by using a helicon pre-ionization source

    SciTech Connect (OSTI)

    Hossack, Aaron C.; Jarboe, Thomas R.; Victor, Brian S. [Department of Aeronautics and Astronautics, University of Washington, Seattle, Washington 98195 (United States)] [Department of Aeronautics and Astronautics, University of Washington, Seattle, Washington 98195 (United States); Firman, Taylor; Prager, James R.; Ziemba, Timothy [Eagle Harbor Technologies, Inc., 119 W. Denny Way, Suite 210, Seattle, Washington 98119 (United States)] [Eagle Harbor Technologies, Inc., 119 W. Denny Way, Suite 210, Seattle, Washington 98119 (United States); Wrobel, Jonathan S. [979B West Moorhead Circle, Boulder, Colorado 80305 (United States)] [979B West Moorhead Circle, Boulder, Colorado 80305 (United States)

    2013-10-15T23:59:59.000Z

    A helicon based pre-ionization source has been developed and installed on the Helicity Injected Torus with Steady Inductance (HIT-SI) spheromak. The source initiates plasma breakdown by injecting impurity-free, unmagnetized plasma into the HIT-SI confinement volume. Typical helium spheromaks have electron density reduced from (2–3) × 10{sup 19} m{sup ?3} to 1 × 10{sup 19} m{sup ?3}. Deuterium spheromak formation is possible with density as low as 2 × 10{sup 18} m{sup ?3}. The source also enables HIT-SI to be operated with only one helicity injector at injector frequencies above 14.5 kHz. A theory explaining the physical mechanism driving the reduction of breakdown density is presented.

  16. 2D Axisymmetric Coupled CFD-kinetics Modeling of a Nonthermal Arc Plasma Torch for Diesel Fuel

    E-Print Network [OSTI]

    Boyer, Edmond

    1 2D Axisymmetric Coupled CFD-kinetics Modeling of a Nonthermal Arc Plasma Torch for Diesel Fuel-assisted diesel fuel reformer developed for two different applications: (i) onboard H2 production for fuel cell. In the first case, diesel fuel reacts with air while in the second case it reacts with diesel engine exhaust

  17. The effect of magnetic field on bistability in 1D photonic crystal doped by magnetized plasma and coupled nonlinear defects

    SciTech Connect (OSTI)

    Mehdian, H.; Mohammadzahery, Z.; Hasanbeigi, A. [Department of Physics and Institute for Plasma Research, Kharazmi University, 49 Dr Mofatteh Avenue, Tehran 15614 (Iran, Islamic Republic of)] [Department of Physics and Institute for Plasma Research, Kharazmi University, 49 Dr Mofatteh Avenue, Tehran 15614 (Iran, Islamic Republic of)

    2014-01-15T23:59:59.000Z

    In this work, we study the defect mode and bistability behavior of 1-D photonic band gap structure with magnetized plasma and coupled nonlinear defects. The transfer matrix method has been employed to investigate the magnetic field effect on defect mode frequency and bistability threshold. The obtained results show that the frequency of defect mode and bistability threshold can be altered, without changing the structure of the photonic multilayer. Therefore, the bistability behavior of the subjected structure in the presence of magnetized plasma can be utilized in manufacturing wide frequency range devices.

  18. Spectroscopy diagnostic of dual-frequency capacitively coupled CHF{sub 3}/Ar plasma

    SciTech Connect (OSTI)

    Liu, Wen-Yao; Du, Yong-Quan [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China)] [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China); Liu, Yong-Xin; Liu, Jia; Zhao, Tian-Liang; Wang, You-Nian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Xu, Yong; Li, Xiao-Song; Zhu, Ai-Min [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China) [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China); School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2013-11-15T23:59:59.000Z

    A combined spectroscopic method of absorption, actinometry, and relative optical emission intensity is employed to determine the absolute CF{sub 2} density, the relative F and H densities, H atom excitation temperature and the electron density in dual-frequency (60/2 MHz) capacitively coupled CHF{sub 3}/Ar plasmas. The effects of different control parameters, such as high-frequency (HF) power, low-frequency (LF) power, gas pressure, gap length and content of CHF{sub 3}, on the concentration of radical CF{sub 2}, F, and H and excitation temperature are discussed, respectively. It is found that the concentration of CF{sub 2} is strongly dependent on the HF power, operating pressure and the proportion of CHF{sub 3} in feed gas, while it is almost independent of the LF power and the gap length. A higher concentration ratio of F to CF{sub 2} could be obtained in dual-frequency discharge case. Finally, the generation and decay mechanisms of CF{sub 2} and F were also discussed.

  19. Influence of microwave driver coupling design on plasma density at Testbench for Ion sources Plasma Studies, a 2.45 GHz Electron Cyclotron Resonance Plasma Reactor

    SciTech Connect (OSTI)

    Megía-Macías, A.; Vizcaíno-de-Julián, A. [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain)] [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain); Cortázar, O. D., E-mail: dcortazar@essbilbao.org [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain); Universidad de Castilla-La Mancha, ETSII, C.J. Cela s/n, 13170 Ciudad Real (Spain)

    2014-03-15T23:59:59.000Z

    A comparative study of two microwave driver systems (preliminary and optimized) for a 2.45 GHz hydrogen Electron Cyclotron Resonance plasma generator has been conducted. The influence on plasma behavior and parameters of stationary electric field distribution in vacuum, i.e., just before breakdown, along all the microwave excitation system is analyzed. 3D simulations of resonant stationary electric field distributions, 2D simulations of external magnetic field mapping, experimental measurements of incoming and reflected power, and electron temperature and density along the plasma chamber axis have been carried out. By using these tools, an optimized set of plasma chamber and microwave coupler has been designed paying special attention to the optimization of stationary electric field value in the center of the plasma chamber. This system shows a strong stability on plasma behavior allowing a wider range of operational parameters and even sustaining low density plasma formation without external magnetic field. In addition, the optimized system shows the capability to produce values of plasma density four times higher than the preliminary as a consequence of a deeper penetration of the magnetic resonance surface in relative high electric field zone by keeping plasma stability. The increment of the amount of resonance surface embedded in the plasma under high electric field is suggested as a key factor.

  20. Uncertainty Measurement for Trace Element Analysis of Uranium and Plutonium Samples by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)

    SciTech Connect (OSTI)

    Gallimore, David L. [Los Alamos National Laboratory

    2012-06-13T23:59:59.000Z

    The measurement uncertainty estimatino associated with trace element analysis of impurities in U and Pu was evaluated using the Guide to the Expression of Uncertainty Measurement (GUM). I this evalution the uncertainty sources were identified and standard uncertainties for the components were categorized as either Type A or B. The combined standard uncertainty was calculated and a coverage factor k = 2 was applied to obtain the expanded uncertainty, U. The ICP-AES and ICP-MS methods used were deveoped for the multi-element analysis of U and Pu samples. A typical analytical run consists of standards, process blanks, samples, matrix spiked samples, post digestion spiked samples and independent calibration verification standards. The uncertainty estimation was performed on U and Pu samples that have been analyzed previously as part of the U and Pu Sample Exchange Programs. Control chart results and data from the U and Pu metal exchange programs were combined with the GUM into a concentration dependent estimate of the expanded uncertainty. Comparison of trace element uncertainties obtained using this model was compared to those obtained for trace element results as part of the Exchange programs. This process was completed for all trace elements that were determined to be above the detection limit for the U and Pu samples.

  1. High-Sensitivity Analysis of Human Plasma Proteome by Immobilized Isoelectric Focusing Fractionation Coupled to Mass

    E-Print Network [OSTI]

    Tian, Weidong

    High-Sensitivity Analysis of Human Plasma Proteome by Immobilized Isoelectric Focusing of complex biological samples. Keywords: plasma · immobilized pH gradients · isoelectric focusing of Sciences, Shanghai, 200031, China Received December 24, 2004 Immobilized pH gradients isoelectric focusing

  2. The determination of sulfur-containing surfactants with a high pressure liquid chromatography-inductively coupled plasma emission spectrometry system

    E-Print Network [OSTI]

    Hobill, Jonathan Edward

    1987-01-01T23:59:59.000Z

    of the blank millivolt intensities 78 17 Average millivolt intensities for the nickel standard solution 79 Table Page 18 Standard deviations of the nickel standard millivolt intensities 80 19 Slopes of the calibration lines calculated from the blank... widely used sulfur-containing surfactants. The alkylbenzenesulfonates 1 strongly absorb in the UV region and, therefore are easily monitored by UV detectors. Other surfactants, such as alkyl sulfates 2 [13-17], alpha olefin sulfonates 3 [16...

  3. FIRST STEP IN THEORETICAL APPROACH IN STUDY OF MARS AND TITAN ATMOSPHERES WITH AN INDUCTIVELY COUPLED PLASMA TORCH

    E-Print Network [OSTI]

    with the titan atmosphere (CH4-N2) unlike the Mars atmosphere (CO2-N2). We observe the creation of solid], one can obtain the molar fraction versus temperature. The composition of Mars is assumed to be 97% CO22, CO2 - , N2O, N2O3, N2O4, N2O5, N2O+, N3, NCN, NO2, NO2 - , NO3, O3 and the electrons

  4. Size exclusion chromatography-inductively coupled plasma atomic emission spectrographic study of Fe in bitumens derived from tar sands

    SciTech Connect (OSTI)

    Reynolds, J.G. (Lawrence Livermore National Lab., Livermore, CA (US)); Biggs, W.R. (Chevron Research Co., Richmond, CA (US))

    1992-01-01T23:59:59.000Z

    This paper reports on bitumens extracted from tar sands from various locations (Utah, California, Kentucky, and Alberta) that were examined by size exclusion chromatography with on-line element-specific detection to study the Fe concentration as a function of size. In most cases, the resulting profiles exhibit unimodal distributions at relatively large molecular size with very similar times for maximum elution. specifically, Sunnyside (Utah) and McKittrick (California) tar-sand bitumens exhibited very intense maxima consistent with extremely high bulk Fe contents. Arroyo Grande (California) exhibited an additional maximum at very large molecular size. This size behavior of the Fe appears to correlate with the large molecular size Ni and V components eluted under the same conditions.

  5. COMPARISON OF LEAD CONCENTRATION IN SURFACE SOIL BY INDUCTED COUPLED PLASMA/OPTICAL EMISSION SPECTROMETRY AND X-RAY FLUORESCENCE

    E-Print Network [OSTI]

    Boyer, Edmond

    , where a secondary lead smelter had been operating for a long time, was investigated. The objective, since a secondary lead smelter had been operating for a long time in the village and some contaminated

  6. Chapter 6.25 Cambridge Fiji F200 Plasma ALD

    E-Print Network [OSTI]

    Healy, Kevin Edward

    system supports metal ALD primarily and has a remote inductively coupled plasma source to allow for low to keep electromagnetically sensitive devices such as cell phones away from the ICP coil. 4.2 Heating 4.2.1 Heater : The PEALD system includes several heating elements to bring various components to temperature

  7. Pressure and arc voltage coupling in dc plasma torches: Identification and extraction of oscillation modes

    SciTech Connect (OSTI)

    Rat, V.; Coudert, J. F. [SPCTS UMR 6638, CNRS-University of Limoges, 123 Av. A. Thomas, 87060 Limoges Cedex (France)

    2010-08-15T23:59:59.000Z

    This work is devoted to the instabilities occurring in a plasma torch, such as those found in plasma spraying. These instabilities are responsible for a lack of reproducibility of coatings properties, especially in the case of suspension plasma spraying that is an innovative way to obtain thin coatings of submicron-sized particles. Strong Helmholtz oscillations are highlighted in the plasma flow and it is demonstrated that they overlap with different acoustic modes in addition with the more commonly admitted ''restrike'' mode, the later being due to rearcing events in the arc region. The instabilities occur in the arc voltage but it is experimentally shown in this paper that the pressure within the torch body presents the same kind of instabilities. Besides, a numerical filtering technique has been adapted to isolate the different instability components. The operating parameters of the plasma torch were varied in order to highlight their influence on the amplitude of the different modes, both for the arc voltage and the pressure.

  8. Coupled modes in magnetized dense plasma with relativistic-degenerate electrons

    SciTech Connect (OSTI)

    Khan, S. A. [National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320 (Pakistan)

    2012-01-15T23:59:59.000Z

    Low frequency electrostatic and electromagnetic waves are investigated in ultra-dense quantum magnetoplasma with relativistic-degenerate electron and non-degenerate ion fluids. The dispersion relation is derived for mobile as well as immobile ions by employing hydrodynamic equations for such plasma under the influence of electromagnetic forces and pressure gradient of relativistic-degenerate Fermi gas of electrons. The result shows the coexistence of shear Alfven and ion modes with relativistically modified dispersive properties. The relevance of results to the dense degenerate plasmas of astrophysical origin (for instance, white dwarf stars) is pointed out with brief discussion on ultra-relativistic and non-relativistic limits.

  9. Laser ablation of electronic materials including the effects of energy coupling and plasma interactions

    SciTech Connect (OSTI)

    Zeng, Xianzhong

    2004-12-10T23:59:59.000Z

    Many laser ablation applications such as laser drilling and micromachining generate cavity structures. The study of laser ablation inside a cavity is of both fundamental and practical significance. In this dissertation, cavities with different aspect ratios (depth/diameter) were fabricated in fused silica by laser micromachining. Pulsed laser ablation in the cavities was studied and compared with laser ablation on a flat surface. The formation of laser-induced plasmas in the cavities and the effects of the cavities on the ablation processes were investigated. The temperatures and electron number densities of the resulting laser-induced plasmas in the cavities were determined from spectroscopic measurements. Reflection and confinement effects by the cavity walls and plasma shielding were discussed to explain the increased temperature and electron number density with respect to increasing cavity aspect ratio. The temporal variations of the plasma temperature and electron number density inside the cavity decreased more rapidly than outside the cavity. The effect of laser energy on formation of a plasma inside a cavity was also investigated. Propagation of the shock wave generated during pulsed laser ablation in cavities was measured using laser shadowgraph imaging and compared with laser ablation on a flat surface. It is found that outside the cavity, after about 30 ns the radius of the expanding shock wave was proportional to t2/5, which corresponds to a spherical blast wave. The calculated pressures and temperatures of the shocked air outside of the cavities were higher than those obtained on the flat surface. Lasers with femtosecond pulse duration are receiving much attention for direct fabrication of microstructures due to their capabilities of high-precision ablation with minimal damage to the sample. We have also performed experimental studies of pulsed femtosecond laser ablation on the flat surface of silicon samples and compared results with pulsed nanosecond laser ablation at a ultraviolet wavelength (266 nm). Crater depth measurements indicated that ablation efficiency was enhanced for UV femtosecond laser pulses. The electron number densities and temperatures of femtosecond-pulse plasmas decreased faster than nanosecond-pulse plasmas due to different energy deposition mechanisms. Plasma expansion in both the perpendicular and the lateral directions were studied.

  10. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 27, NO. 2, APRIL 1999 555 Coupled Thermal-Electromagnetic

    E-Print Network [OSTI]

    Jerby, Eli

    of the temperature and power-dissipation profiles. Variations in the (microwave) impedance profile in the medium due impedance profile for the incident wave and therefore acts as a nonlinear distributed load. Coupled thermal heaters in which the heated material acts as a nonlinear load in the microwave circuit. Index Terms

  11. Recent Results on Coupling Fast Waves to High Performance Plasmas on DIII-D

    E-Print Network [OSTI]

    Porkolab, Miklos

    Fast Waves (FWs) at 60 MHz and 90 MHz are used in DIII?D for central electron heating and current drive. Coupling of FWs to high?performance discharges is limited by low antenna loading in these regimes. To extend the ...

  12. VELOCITY-SHEAR-INDUCED MODE COUPLING IN THE SOLAR ATMOSPHERE AND SOLAR WIND: IMPLICATIONS FOR PLASMA HEATING AND MHD TURBULENCE

    SciTech Connect (OSTI)

    Hollweg, Joseph V.; Chandran, Benjamin D. G. [Space Science Center, Morse Hall, University of New Hampshire, Durham, NH 03824 (United States); Kaghashvili, Edisher Kh., E-mail: joe.hollweg@unh.edu, E-mail: ekaghash@aer.com, E-mail: benjamin.chandran@unh.edu [Atmospheric and Environmental Research, A Verisk Analytics Company, 131 Hartwell Avenue, Lexington, MA 02421 (United States)

    2013-06-01T23:59:59.000Z

    We analytically consider how velocity shear in the corona and solar wind can cause an initial Alfven wave to drive up other propagating signals. The process is similar to the familiar coupling into other modes induced by non-WKB refraction in an inhomogeneous plasma, except here the refraction is a consequence of velocity shear. We limit our discussion to a low-beta plasma, and ignore couplings into signals resembling the slow mode. If the initial Alfven wave is propagating nearly parallel to the background magnetic field, then the induced signals are mainly a forward-going (i.e., propagating in the same sense as the original Alfven wave) fast mode, and a driven signal propagating like a forward-going Alfven wave but polarized like the fast mode; both signals are compressive and subject to damping by the Landau resonance. For an initial Alfven wave propagating obliquely with respect to the magnetic field, the induced signals are mainly forward- and backward-going fast modes, and a driven signal propagating like a forward-going Alfven wave but polarized like the fast mode; these signals are all compressive and subject to damping by the Landau resonance. A backward-going Alfven wave, thought to be important in the development of MHD turbulence, is also produced, but it is very weak. However, we suggest that for oblique propagation of the initial Alfven wave the induced fast-polarized signal propagating like a forward-going Alfven wave may interact coherently with the initial Alfven wave and distort it at a strong-turbulence-like rate.

  13. Quark spectral density and a strongly-coupled quark-gluon plasma.

    SciTech Connect (OSTI)

    Qin, S.; Chang, L.; Liu, Y.; Roberts, C. D. (Physics); (Peking Univ.); (Inst. of Applied Physics and Computational Mathematics); (National Lab. of Heavy Ion Accelerator)

    2011-07-13T23:59:59.000Z

    The maximum entropy method is used to compute the dressed-quark spectral density from the self-consistent numerical solution of a rainbow truncation of QCD's gap equation at temperatures above that for which chiral symmetry is restored. In addition to the normal and plasmino modes, the spectral function also exhibits an essentially nonperturbative zero mode for temperatures extending to 1.4-1.8 times the critical temperature, T{sub c}. In the neighborhood of T{sub c}, this long-wavelength mode contains the bulk of the spectral strength and as long as this mode persists, the system may fairly be described as a strongly-coupled state of matter.

  14. Polymer Chains and Baryons in a Strongly Coupled Quark-Gluon Plasma

    E-Print Network [OSTI]

    Jinfeng Liao; Edward V. Shuryak

    2005-11-03T23:59:59.000Z

    Recently there was a significant change of views on physical properties and underlying dynamics of Quark-Gluon Plasma at $T=170-350 MeV$, produced in heavy ion collisions at RHIC. Instead of being a gas of $q,g$ quasiparticles, a near-perfect liquid is observed. Also, precisely in this temperature interval, the interaction deduced from lattice studies is strong enough to support multiple binary bound states. This work is the first variational study of {\\em multibody} bound states. We will consider: (i) ``polymer chains'' of the type $\\bar q g g ..g q$; (ii) baryons $(qqq)$; (iii) closed (3-)chains of gluons $(ggg)$. We found that chains (i) form in exactly the same $T$ range as binary states, with the same binding {\\em per bond}. The binding and $T$-range for diquarks, baryons and closed 3-chains are also established. We point out that the presence of chains, or possibly even a chain network, may drastically change the transport properties of matter, such as charm diffusion or jet energy loss. We further suggest that it seems to exist only for $T=(1-1.5)T_c$ and thus there may be a ``latent period'' for charm/jet quenching in RHIC collisions, while matter cools down to such $T$.

  15. Combined effects of gas pressure and exciting frequency on electron energy distribution functions in hydrogen capacitively coupled plasmas

    SciTech Connect (OSTI)

    Abdel-Fattah, E. [Physics Department, Faculty of Science, Zagazig University, Zagazig 44519 (Egypt); Sugai, H. [Department of Electronics and Information Engineering, Chubu University, 1200 Matsumoto-cho, Kasugai 487-8501 (Japan)

    2013-02-15T23:59:59.000Z

    The combined effects of the variation of hydrogen pressure (40-400 mTorr) and exciting frequency (13.56-50 MHz) on the electron energy probability function (EEPF) and other plasma parameters in capacitively coupled hydrogen H{sub 2} discharge at fixed discharge voltage were investigated using rf-compensated Langmuir probe. At a fixed exciting frequency of 13.56 MHz, the EEPF evolved from Maxwellian-like distribution to a bi-Maxwellian distribution when the H{sub 2} pressure increased, possibly due to efficient vibrational excitation. The electron density largely increased to a peak value and then decreased with the increase of H{sub 2} pressure. Meanwhile, the electron temperature and plasma potential significantly decrease and reaching a minimum at 120 mTorr beyond, which saturated or slightly increases. On the other hand, the dissipated power and electron density markedly increased with increasing the exciting frequency at fixed H{sub 2} pressure and voltage. The electron temperatures negligibly dependent on the driving frequency. The EEPFs at low pressure 60 mTorr resemble Maxwellian-like distribution and evolve into a bi-Maxwellian type as frequency increased, due to a collisonless (stochastic) sheath-heating in the very high frequency regime, while the EEPF at hydrogen pressure {>=}120 mTorr retained a bi-Maxwellian-type distribution irrespective of the driving frequency. Such evolution of the EEPFs shape with the driving frequency and hydrogen pressure has been discussed on the basis of electron diffusion processes and low threshold-energy inelastic collision processes taking place in the discharge. The ratio of stochastic power to bulk power heating ratio is dependent on the hydrogen pressure while it is independent on the driving frequency.

  16. Periodic patterning stem cells and induction of skin appendages: p-ERK-dependent mes-enchymal condensation is coupled with Turing mechanism to convert stripes to spots

    E-Print Network [OSTI]

    Maini, Philip K.

    ABSTRACTS 931 Periodic patterning stem cells and induction of skin appendages: p-ERK-dependent mes patterns remains unknown. Using the feather model, here we show ERK activity-dependent mesenchymal cell chemotaxis toward initial peaks is essential for completing pattern formation. Adding ERK inhibitors produced

  17. Plasma ignition and steady state simulations of the Linac4 H$^{-}$ ion source

    E-Print Network [OSTI]

    Mattei, S; Yasumoto, M; Hatayama, A; Lettry, J; Grudiev, A

    2013-01-01T23:59:59.000Z

    The RF heating of the plasma in the Linac4 H- ion source has been simulated using an Particle-in-Cell Monte Carlo Collision method (PIC-MCC). This model is applied to investigate the plasma formation starting from an initial low electron density of 1012 m-3 and its stabilization at 1018 m-3. The plasma discharge at low electron density is driven by the capacitive coupling with the electric field generated by the antenna, and as the electron density increases the capacitive electric field is shielded by the plasma and induction drives the plasma heating process. Plasma properties such as e-/ion densities and energies, sheath formation and shielding effect are presented and provide insight to the plasma properties of the hydrogen plasma.

  18. Coupling of laser energy into plasma channels D. A. Dimitrov, R. E. Giacone, D. L. Bruhwiler, and R. Busby

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    ramp leads to an actual focus at the top of the ramp due to plasma focusing, resulting in reduced spot

  19. Plasma generation for controlled microwave-reflecting surfaces in plasma antennas

    SciTech Connect (OSTI)

    Bliokh, Yury P.; Felsteiner, Joshua; Slutsker, Yakov Z. [Physics Department, Technion-Israel Institute of Technology, 32000 Haifa (Israel)

    2014-04-28T23:59:59.000Z

    The idea of replacing metal antenna elements with equivalent plasma objects has long been of interest because of the possibility of switching the antenna on and off. In general, two kinds of designs have so far been reported: (a) Separate plasma “wires” which are thin glass tubes filled with gas, where plasma appears due to discharge inside. (b) Reflecting surfaces, consisting of tightly held plasma wires or specially designed large discharge devices with magnetic confinement. The main disadvantages of these antennas are either large weight and size or too irregular surfaces for proper reflection. To design a microwave plasma antenna in the most common radar wavelength range of 1–3?cm with a typical gain of 30?dB, a smooth plasma mirror having a 10–30?cm diameter and a proper curvature is required. The plasma density must be 10{sup 12}–10{sup 14}?cm{sup ?3} in order to exceed the critical density for the frequency of the electromagnetic wave. To achieve this we have used a ferromagnetic inductively coupled plasma (FICP) source, where a thin magnetic core of a large diameter is fully immersed in the plasma. In the present paper, we show a way to adapt the FICP source for creating a flat switchable microwave plasma mirror with an effective diameter of 30?cm. This mirror was tested as a microwave reflector and there was found no significant difference when compared with a copper plate having the same diameter.

  20. Generation of uniform plasmas by crossed internal oscillating current sheets: Key concepts and experimental verification

    SciTech Connect (OSTI)

    Tsakadze, E.L.; Ostrikov, K.; Tsakadze, Z.L.; Xu, S. [Plasma Sources and Applications Center, NIE, Nanyang Technological University, 1 Nanyang Walk, 637616 Singapore and Optics and Plasma Research Department, Risoe National Laboratory, P.O. Box 49, DK-4000 Roskilde (Denmark); School of Physics, The University of Sydney, New South Wales 2006 (Australia); Plasma Sources and Applications Center, NIE, Nanyang Technological University, 1 Nanyang Walk, 637616 Singapore (Singapore)

    2005-01-01T23:59:59.000Z

    The results of comprehensive experimental studies of the operation, stability, and plasma parameters of the low-frequency (0.46 MHz) inductively coupled plasmas sustained by the internal oscillating rf current are reported. The rf plasma is generated by using a custom-designed configuration of the internal rf coil that comprises two perpendicular sets of eight currents in each direction. Various diagnostic tools, such as magnetic probes, optical emission spectroscopy, and an rf-compensated Langmuir probe were used to investigate the electromagnetic, optical, and global properties of the argon plasma in wide ranges of the applied rf power and gas feedstock pressure. It is found that the uniformity of the electromagnetic field inside the plasma reactor is improved as compared to the conventional sources of inductively coupled plasmas with the external flat coil configuration. A reasonable agreement between the experimental data and computed electromagnetic field topography inside the chamber is reported. The Langmuir probe measurements reveal that the spatial profiles of the electron density, the effective electron temperature, plasma potential, and electron energy distribution/probability functions feature a high degree of the radial and axial uniformity and a weak azimuthal dependence, which is consistent with the earlier theoretical predictions. As the input rf power increases, the azimuthal dependence of the global plasma parameters vanishes. The obtained results demonstrate that by introducing the internal oscillated rf currents one can noticeably improve the uniformity of electromagnetic field topography, rf power deposition, and the plasma density in the reactor.

  1. Wave frequency dependence of H{sup -} ion production and extraction in a transformer coupled plasma H{sup -} ion source at SNU

    SciTech Connect (OSTI)

    An, Young Hwa; Cho, Won Hwi; Chung, Kyoung-Jae; Lee, Kern; Jang, Seung Bin; Lee, Seok-Geun; Hwang, Y. S. [Department of Nuclear Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of)

    2012-02-15T23:59:59.000Z

    The effect of rf wave frequencies on the production of H{sup -} ion is investigated in a transformer coupled plasma H{sup -} ion source at Seoul National University. A Langmuir probe is installed to measure the plasma density and temperature, and these plasma parameters are correlated to the extracted H{sup -} beam currents at various frequencies. The Langmuir probe is also used to measure the density of H{sup -} ions at the ion source by generating photodetachment with an Nd:YAG laser. The extracted H{sup -} currents decrease to a minimum value until 13 MHz and then, increase as the driving frequency increases from 13 MHz while the relative H{sup -} population measured by photodetachment monotonically decreases as the driving rf frequency increases from 11 MHz to 15 MHz. A potential well formed at the extraction region at high frequencies of more than 13 MHz is considered responsible for the increased H{sup -} beam extraction even with a lower photodetachment signal. The variation in the driving rf frequency not only affects the density and temperature of the plasma but also modifies the plasma potential with the existence of a filtering magnetic field and consequently, influences the extracted H{sup -} current through the extraction as well as formation of H{sup -} ions.

  2. An Experimental Study of Waveguide Coupled Microwave Heating with Conventional Multicusp Negative Ion Source

    E-Print Network [OSTI]

    Komppula, J; Koivisto, H; Laulainen, J; Tarvainen, O

    2015-01-01T23:59:59.000Z

    Negative ion production with conventional multicusp plasma chambers utilizing 2.45 GHz microwave heating is demonstrated. The experimental results were obtained with the multicusp plasma chambers and extraction systems of the RFdriven RADIS ion source and the filament driven arc discharge ion source LIISA. A waveguide microwave coupling system, which is almost similar to the one used with the SILHI ion source, was used. The results demonstrate that at least one third of negative ion beam obtained with inductive RF-coupling (RADIS) or arc discharge (LIISA) can be achieved with 1 kW of 2.45 GHz microwave power in CW mode without any modification of the plasma chamber. The co-extracted electron to H^- ratio and the optimum pressure range were observed to be similar for both heating methods. The behaviour of the plasma implies that the energy transfer from the microwaves to the plasma electrons is mainly an off-resonance process.

  3. Plasma Chemistries for High Density Plasma Etching of SiC

    SciTech Connect (OSTI)

    Cho, H.; Hahn, Y.B.; Hays, D.A.; Hong, J.; Jung, K.B.; Lester, L.F.; Ostling, M.; Pearton, S.J.; Shul, R.J.; Zetterling, C.-M; Zhang, L.

    1998-11-10T23:59:59.000Z

    A variety of different plasma chemistries, including SF6, Cl2, IC1 and IBr, have been examined for dry etching of 6H-SiC in high ion density plasma tools (Inductively Coupled Plasma and Electron Cyclotron Resonance). Rates up to 4,500~"min-1 were obtained for SF6 plasmas, while much lower rates (S800~.min-') were achieved with Cl2, ICl and IBr. The F2- based chemistries have poor selectivity for SiC over photoresist masks (typically 0.4-0.5), but Ni masks are more robust, and allow etch depths 210pm in the SiC. A micromachining process (sequential etch/deposition (<2,000Angstrom min-1) for SiC steps) designed for Si produces relatively low etch rates.

  4. Non-ambipolar radio-frequency plasma electron source and systems and methods for generating electron beams

    DOE Patents [OSTI]

    Hershkowitz, Noah (Madison, WI); Longmier, Benjamin (Madison, WI); Baalrud, Scott (Madison, WI)

    2009-03-03T23:59:59.000Z

    An electron generating device extracts electrons, through an electron sheath, from plasma produced using RF fields. The electron sheath is located near a grounded ring at one end of a negatively biased conducting surface, which is normally a cylinder. Extracted electrons pass through the grounded ring in the presence of a steady state axial magnetic field. Sufficiently large magnetic fields and/or RF power into the plasma allow for helicon plasma generation. The ion loss area is sufficiently large compared to the electron loss area to allow for total non-ambipolar extraction of all electrons leaving the plasma. Voids in the negatively-biased conducting surface allow the time-varying magnetic fields provided by the antenna to inductively couple to the plasma within the conducting surface. The conducting surface acts as a Faraday shield, which reduces any time-varying electric fields from entering the conductive surface, i.e. blocks capacitive coupling between the antenna and the plasma.

  5. Preparation of anti-adhesion surfaces on aluminium substrates of rubber plastic moulds using a coupling method of liquid plasma and electrochemical machining

    SciTech Connect (OSTI)

    Meng, Jianbing, E-mail: jianbingmeng@126.com; Dong, Xiaojuan; Wei, Xiuting; Yin, Zhanmin [School of Mechanical Engineering, Shandong University of Technology, Zibo, 255049 (China)] [School of Mechanical Engineering, Shandong University of Technology, Zibo, 255049 (China)

    2014-03-15T23:59:59.000Z

    Hard anti-adhesion surfaces, with low roughness and wear resistance, on aluminium substrates of rubber plastic moulds were fabricated via a new coupling method of liquid plasma and electrochemical machining. With the aid of liquid plasma thermal polishing and electrochemical anodic dissolution, micro/nano-scale binary structures were prepared as the base of the anti-adhesion surfaces. The anti-adhesion behaviours of the resulting aluminium surfaces were analysed by a surface roughness measuring instrument, a scanning electron microscope (SEM), a Fourier-transform infrared spectrophotometer (FTIR), an X-ray diffractometer (XRD), an optical contact angle meter, a digital Vickers micro-hardness (Hv) tester, and electronic universal testing. The results show that, after the liquid plasma and electrochemical machining, micro/nano-scale binary structures composed of micro-scale pits and nano-scale elongated boss structures were present on the sample surfaces. As a result, the anti-adhesion surfaces fabricated by the above coupling method have good anti-adhesion properties, better wear resistance and lower roughness.

  6. Steady-state inductive spheromak operation

    DOE Patents [OSTI]

    Janos, Alan C. (E. Windsor, NJ); Jardin, Stephen C. (Princeton, NJ); Yamada, Masaaki (Lawrenceville, NJ)

    1987-01-01T23:59:59.000Z

    The inductively formed spheromak plasma can be maintained in a highly stable and controlled fashion. Steady-state operation is obtained by forming the plasma in the linked mode, then oscillating the poloidal and toroidal fields such that they have different phases. Preferably, the poloidal and magnetic fields are 90.degree. out of phase.

  7. Inductive tuners for microwave driven discharge lamps

    DOE Patents [OSTI]

    Simpson, James E. (Gaithersburg, MD)

    1999-01-01T23:59:59.000Z

    An RF powered electrodeless lamp utilizing an inductive tuner in the waveguide which couples the RF power to the lamp cavity, for reducing reflected RF power and causing the lamp to operate efficiently.

  8. Induction machine

    DOE Patents [OSTI]

    Owen, Whitney H. (Ogden, UT)

    1980-01-01T23:59:59.000Z

    A polyphase rotary induction machine for use as a motor or generator utilizing a single rotor assembly having two series connected sets of rotor windings, a first stator winding disposed around the first rotor winding and means for controlling the current induced in one set of the rotor windings compared to the current induced in the other set of the rotor windings. The rotor windings may be wound rotor windings or squirrel cage windings.

  9. Effects of obliqueness and strong electrostatic interaction on linear and nonlinear propagation of dust-acoustic waves in a magnetized strongly coupled dusty plasma

    SciTech Connect (OSTI)

    Shahmansouri, M. [Department of Physics, Faculty of Science, Arak University, Arak 38156- 8 8349 (Iran, Islamic Republic of)] [Department of Physics, Faculty of Science, Arak University, Arak 38156- 8 8349 (Iran, Islamic Republic of); Mamun, A. A. [Department of Physics, Jahangirnagar University, Savar, Dhaka-1342 (Bangladesh)] [Department of Physics, Jahangirnagar University, Savar, Dhaka-1342 (Bangladesh)

    2014-03-15T23:59:59.000Z

    Linear and nonlinear propagation of dust-acoustic waves in a magnetized strongly coupled dusty plasma is theoretically investigated. The normal mode analysis (reductive perturbation method) is employed to investigate the role of ambient/external magnetic field, obliqueness, and effective electrostatic dust-temperature in modifying the properties of linear (nonlinear) dust-acoustic waves propagating in such a strongly coupled dusty plasma. The effective electrostatic dust-temperature, which arises from strong electrostatic interactions among highly charged dust, is considered as a dynamical variable. The linear dispersion relation (describing the linear propagation characteristics) for the obliquely propagating dust-acoustic waves is derived and analyzed. On the other hand, the Korteweg-de Vries equation describing the nonlinear propagation of the dust-acoustic waves (particularly, propagation of dust-acoustic solitary waves) is derived and solved. It is shown that the combined effects of obliqueness, magnitude of the ambient/external magnetic field, and effective electrostatic dust-temperature significantly modify the basic properties of linear and nonlinear dust-acoustic waves. The results of this work are compared with those observed by some laboratory experiments.

  10. Measurement of elemental speciation by liquid chromatography -- inductively coupled plasma mass spectrometry (LC-ICP-MS) with the direct injection nebulizer (DIN)

    SciTech Connect (OSTI)

    Shum, S.

    1993-05-01T23:59:59.000Z

    This thesis is divided into 4 parts: elemental speciation, speciation of mercury and lead compounds by microbore column LC-ICP-MS with direct injection nebulization, spatially resolved measurements of size and velocity distributions of aerosol droplets from a direct injection nebulizer, and elemental speciation by anion exchange and size exclusion chromatography with detection by ICP-MS with direct injection nebulization. Tabs, figs, refs.

  11. Fabrication of Two-Dimensional Photonic Crystals in AlGaInP/GaInP Membranes by Inductively Coupled Plasma Etching

    E-Print Network [OSTI]

    Chen, A.

    The fabrication process of two-dimensional photonic crystals in an AlGaInP/GaInP multi-quantum-well membrane structure is developed. The process includes high resolution electron-beam lithography, pattern transfer into ...

  12. Accurate determination of Curium and Californium isotopic ratios by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) in 248Cm samples for transmutation studies

    SciTech Connect (OSTI)

    Gourgiotis, A.; Isnard, H.; Aubert, M.; Dupont, E.; AlMahamid, I.; Cassette, P.; Panebianco, S.; Letourneau, A.; Chartier, F.; Tian, G.; Rao, L.; Lukens, W.

    2011-02-01T23:59:59.000Z

    The French Atomic Energy Commission has carried out several experiments including the mini-INCA (INcineration of Actinides) project for the study of minor-actinide transmutation processes in high intensity thermal neutron fluxes, in view of proposing solutions to reduce the radiotoxicity of long-lived nuclear wastes. In this context, a Cm sample enriched in {sup 248}Cm ({approx}97 %) was irradiated in thermal neutron flux at the High Flux Reactor (HFR) of the Laue-Langevin Institute (ILL). This work describes a quadrupole ICP-MS (ICP-QMS) analytical procedure for precise and accurate isotopic composition determination of Cm before sample irradiation and of Cm and Cf after sample irradiation. The factors that affect the accuracy and reproducibility of isotopic ratio measurements by ICP-QMS, such as peak centre correction, detector dead time, mass bias, abundance sensitivity and hydrides formation, instrumental background, and memory blank were carefully evaluated and corrected. Uncertainties of the isotopic ratios, taking into account internal precision of isotope ratio measurements, peak tailing, and hydrides formations ranged from 0.3% to 1.3%. This uncertainties range is quite acceptable for the nuclear data to be used in transmutation studies.

  13. Standard test method for determination of impurities in plutonium: acid dissolution, ion exchange matrix separation, and inductively coupled plasma-atomic emission spectroscopic (ICP/AES) analysis

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2003-01-01T23:59:59.000Z

    1.1 This specification covers blended uranium trioxide (UO3), U3O8, or mixtures of the two, powders that are intended for conversion into a sinterable uranium dioxide (UO2) powder by means of a direct reduction process. The UO2 powder product of the reduction process must meet the requirements of Specification C 753 and be suitable for subsequent UO2 pellet fabrication by pressing and sintering methods. This specification applies to uranium oxides with a 235U enrichment less than 5 %. 1.2 This specification includes chemical, physical, and test method requirements for uranium oxide powders as they relate to the suitability of the powder for storage, transportation, and direct reduction to UO2 powder. This specification is applicable to uranium oxide powders for such use from any source. 1.3 The scope of this specification does not comprehensively cover all provisions for preventing criticality accidents, for health and safety, or for shipping. Observance of this specification does not relieve the user of th...

  14. Spatially resolved measurements of ion density and electron temperature in a dual-frequency capacitively coupled plasma by complete floating double probe technique

    SciTech Connect (OSTI)

    Jiang Xiangzhan; Liu Yongxin; Yang Shuo; Lu Wenqi; Bi Zhenhua; Li Xiaosong; Wang Younian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2011-01-15T23:59:59.000Z

    Spatially resolved measurements of the ion density and electron temperature in a dual-frequency capacitively coupled Ar discharge plasma are performed with a newly developed complete floating double probe. Axial and radial distributions of the ion density and electron temperature under various high-frequency (HF) power and gas pressure were studied in detail. Both the ion density and the electron temperature increased with increasing HF power. With increasing gas pressure from 1.3 to 9.3 Pa, the radial profile of ion density below the driven electrode experienced a change from ''bimodal'' to ''unimodal'' shape, with better uniformity being achieved at the optimal pressure of about 5 Pa. In addition, changing the axial profile of ion density was also observed with the peak shift toward the powered electrode at higher pressures. The measured results showed satisfying consistency with that of improved two dimensional fluid simulations.

  15. Far-from-equilibrium dynamics of a strongly coupled non-Abelian plasma with non-zero charge density or external magnetic field

    E-Print Network [OSTI]

    Fuini, John F

    2015-01-01T23:59:59.000Z

    Using holography, we study the evolution of a spatially homogeneous, far from equilibrium, strongly coupled N=4 supersymmetric Yang-Mills plasma with a non-zero charge density or a background magnetic field. This gauge theory problem corresponds, in the dual gravity description, to an initial value problem in Einstein-Maxwell theory with homogeneous but anisotropic initial conditions. We explore the dependence of the equilibration process on different aspects of the initial departure from equilibrium and, while controlling for these dependencies, examine how the equilibration dynamics are affected by the presence of a non-vanishing charge density or an external magnetic field. The equilibration dynamics are remarkably insensitive to the addition of even large chemical potentials or magnetic fields; the equilibration time is set primarily by the form of the initial departure from equilibrium. For initial deviations from equilibrium which are well localized in scale, we formulate a simple model for equilibratio...

  16. Far-from-equilibrium dynamics of a strongly coupled non-Abelian plasma with non-zero charge density or external magnetic field

    E-Print Network [OSTI]

    John F. Fuini III; Laurence G. Yaffe

    2015-03-24T23:59:59.000Z

    Using holography, we study the evolution of a spatially homogeneous, far from equilibrium, strongly coupled N=4 supersymmetric Yang-Mills plasma with a non-zero charge density or a background magnetic field. This gauge theory problem corresponds, in the dual gravity description, to an initial value problem in Einstein-Maxwell theory with homogeneous but anisotropic initial conditions. We explore the dependence of the equilibration process on different aspects of the initial departure from equilibrium and, while controlling for these dependencies, examine how the equilibration dynamics are affected by the presence of a non-vanishing charge density or an external magnetic field. The equilibration dynamics are remarkably insensitive to the addition of even large chemical potentials or magnetic fields; the equilibration time is set primarily by the form of the initial departure from equilibrium. For initial deviations from equilibrium which are well localized in scale, we formulate a simple model for equilibration times which agrees quite well with our results.

  17. Models of radiofrequency coupling for negative ion sources

    SciTech Connect (OSTI)

    Cavenago, M.; Petrenko, S. [INFN-LNL, viale dell'Universita n.2, 35020 Legnaro (Italy)

    2012-02-15T23:59:59.000Z

    Radiofrequency heating for ICP (inductively coupled plasma) ion sources depends on the source operating pressure, the presence or absence of a Faraday shield, the driver coil geometry, the frequency used, and the magnetic field configuration: in negative ion source a magnetic filter seems necessary for H{sup -} survival. The result of single particle simulations showing the possibility of electron acceleration in the preglow regime and for reasonable driver chamber radius (15 cm) is reported, also as a function of the static external magnetic field. An effective plasma conductivity, depending not only from electron density, temperature, and rf field but also on static magnetic field is here presented and compared to previous models. Use of this conductivity and of multiphysics tools for a plasma transport and heating model is shown and discussed for a small source.

  18. Steady-state inductive spheromak operation

    DOE Patents [OSTI]

    Janos, A.C.; Jardin, S.C.; Yamada, M.

    1985-02-20T23:59:59.000Z

    The inductively formed spheromak configuration (S-1) can be maintained in a highly stable and controlled fashion. The method described eliminates the restriction to pulsed spheromak plasmas or the use of electrodes for steady-state operation, and, therefore, is a reactor-relevant formation and sustainment method.

  19. Spatially resolvable optical emission spectrometer for analyzing density uniformity of semiconductor process plasma

    SciTech Connect (OSTI)

    Oh, Changhoon; Ryoo, Hoonchul; Lee, Hyungwoo; Hahn, Jae W. [Nano Photonics Laboratory, School of Mechanical Engineering, Yonsei University, 134 Sinchon-dong, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Kim, Se-Yeon; Yi, Hun-Jung [Manufacturing Technology Team, Memory Division, Semiconductor Business, Samsung Electronics, Hwasung-City, Gyeonggi-do 445-701 (Korea, Republic of)

    2010-10-15T23:59:59.000Z

    We proposed a spatially resolved optical emission spectrometer (SROES) for analyzing the uniformity of plasma density for semiconductor processes. To enhance the spatial resolution of the SROES, we constructed a SROES system using a series of lenses, apertures, and pinholes. We calculated the spatial resolution of the SROES for the variation of pinhole size, and our calculated results were in good agreement with the measured spatial variation of the constructed SROES. The performance of the SROES was also verified by detecting the correlation between the distribution of a fluorine radical in inductively coupled plasma etch process and the etch rate of a SiO{sub 2} film on a silicon wafer.

  20. Plasma sweeper. [Patents

    DOE Patents [OSTI]

    Motley, R.W.; Glanz, J.

    1982-10-25T23:59:59.000Z

    A device is described for coupling RF power (a plasma sweeper) from RF power introducing means to a plasma having a magnetic field associated therewith comprises at least one electrode positioned near the plasma and near the RF power introducing means. Means are described for generating a static electric field at the electrode directed into the plasma and having a component substantially perpendicular to the plasma magnetic field such that a non-zero vector cross-product of the electric and magnetic fields exerts a force on the plasma causing the plasma to drift.

  1. Plasma Response to Lithium-Coated Plasma-Facing Components in the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    M.G. Bell, H.W. Kugel, R. Kaita, L.E. Zakharov, H. Schneider, B.P. LeBlanc, D. Mansfield, R.E. Bell, R. Maingi, S. Ding, S.M. Kaye, S.F. Paul, S.P. Gerhardt, J.M. Canik, J.C. Hosea, G. Taylor and the NSTX Research Team

    2009-08-20T23:59:59.000Z

    Experiments in the National Spherical Torus Experiment (NSTX) have shown beneficial effects on the performance of divertor plasmas as a result of applying lithium coatings on the graphite and carbonfiber- composite plasma-facing components. These coatings have mostly been applied by a pair of lithium evaporators mounted at the top of the vacuum vessel which inject collimated streams of lithium vapor towards the lower divertor. In NBI-heated, deuterium H-mode plasmas run immediately after the application of lithium, performance modifications included decreases in the plasma density, particularly in the edge, and inductive flux consumption, and increases in the electron and ion temperatures and the energy confinement time. Reductions in the number and amplitude of ELMs were observed, including complete ELM suppression for periods up to 1.2 s, apparently as a result of altering the stability of the edge. However, in the plasmas where ELMs were suppressed, there was a significant secular increase in the effective ion charge Zeff and the radiated power as a result of increases in the carbon and medium-Z metallic impurities, although not of lithium itself which remained at a very low level in the plasma core, <0.1%. The impurity buildup could be inhibited by repetitively triggering ELMs with the application of brief pulses of an n = 3 radial field perturbation. The reduction in the edge density by lithium also inhibited parasitic losses through the scrape-off layer of ICRF power coupled to the plasma, enabling the waves to heat electrons in the core of H-mode plasmas produced by NBI. Lithium has also been introduced by injecting a stream of chemically stabilized, fine lithium powder directly into the scrape-off layer of NBI-heated plasmas. The lithium was ionized in the SOL and appeared to flow along the magnetic field to the divertor plates. This method of coating produced similar effects to the evaporated lithium but at lower amounts.

  2. Computer Science Induction to

    E-Print Network [OSTI]

    Berger, Ulrich

    Computer Science Induction to Postgraduate Research Studies Ulrich Berger Head of Postgraduate Research Supervision Regulations Progression Regulations Computer Science Induction to Postgraduate Research Studies Ulrich Berger Head of Postgraduate Research Department of Computer Science Swansea

  3. Characterization of an RF plasma ion source for ion implantation

    SciTech Connect (OSTI)

    Kopalidis, Peter M.; Wan Zhimin [Advanced Ion Beam Technology Inc., 47370 Fremont Blvd., Fremont, CA 94538 (United States)

    2012-11-06T23:59:59.000Z

    A novel inductively coupled RF plasma ion source has been developed for use in a beamline ion implanter. Ion density data have been taken with an array of four Langmuir probes spaced equally at the source extraction arc slit. These provide ion density uniformity information as a function of source pressure, RF power and gas mixture composition. In addition, total extracted ion beam current data are presented for the same conditions. The comparative advantages of the RF source in terms of higher beam current, reduced maintenance and overall productivity improvement compared to a hot cathode source are discussed.

  4. Absolute CF{sub 2} density and gas temperature measurements by absorption spectroscopy in dual-frequency capacitively coupled CF{sub 4}/Ar plasmas

    SciTech Connect (OSTI)

    Liu, Wen-Yao; Xu, Yong, E-mail: yongxu@dlut.edu.cn; Peng, Fei; Gong, Fa-Ping; Li, Xiao-Song; Zhu, Ai-Min [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China); Liu, Yong-Xin; Wang, You-Nian [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2014-10-15T23:59:59.000Z

    Broadband ultraviolet absorption spectroscopy has been used to determine the CF{sub 2} radical density in dual-frequency capacitively coupled CF{sub 4}/Ar plasmas, using the CF{sub 2} A{sup ~1}B{sub 1}?X{sup ~1}A{sub 1} system of absorption spectrum. The rotational temperature of ground state CF{sub 2} and excited state CF was also estimated by using A{sup ~1}B{sub 1}?X{sup ~1}A{sub 1} system and B{sup 2}??X{sup 2}? system, respectively. The translational gas temperature was deduced from the Doppler width of the Ar{sup *}({sup 3}P{sub 2}) and Ar{sup *}({sup 3}P{sub 0}) metastable atoms absorption line by using the tunable diode laser absorption spectroscopy. The rotational temperatures of the excited state CF are about 100?K higher than those of ground state CF{sub 2}, and about 200?K higher than the translational gas temperatures. The dependences of the radical CF{sub 2} density, electron density, electron temperature, rotational temperature, and gas temperature on the high frequency power and pressure have been analyzed. Furthermore, the production and loss mechanisms of CF{sub 2} radical and the gas heating mechanisms have also been discussed.

  5. A 1.12pJ/b Resonance Compensated Inductive Transceiver with a Fault-Tolerant Network Controller

    E-Print Network [OSTI]

    Yoo, Hoi-Jun

    . An inductive-coupling transceiver is used for cross-layer communication, and it adopts a resonance compensatorA 1.12pJ/b Resonance Compensated Inductive Transceiver with a Fault-Tolerant Network Controller of Korea jerald@eeinfo.kaist.ac.kr Abstract--A low-energy inductive coupling link with a low energy fault

  6. A Compact Disk Type Plasma Propulsion System with Modulated Magnetic Field for Nanoscale Space Vehicles

    SciTech Connect (OSTI)

    Fukuda, Takeshi; Ueda, Satoshi; Ohnishi, Yukihiro; Inomoto, Michiaki [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, 565-0871 Osaka (Japan)

    2008-12-31T23:59:59.000Z

    A compact 5 mm disk type plasma thruster simply composed of only a set of antenna windings and bias field coil which produces significant thrust of 0.74 mN with rotating magnetic field has been proposed and successfully developed for future applications to low altitude nanosatellites. The key technology issue is that the rotating speed is set above the ion plasma frequency but far below the electron plasma frequency, in order to produce the electron drag current and axial electric field as a consequence of the interaction with the bias field. The formation of axial electric field was confirmed and the produced plasma density was >6x10{sup 18} m{sup -3}, whereas the power consumption is 500 W in the inductively coupled mode of operation. The anticipated thrust density and specific thrust could potentially be extended to 7.64 Nm{sup -2} and 850 s, respectively, which is comparable to conventional Hall effect thrusters.

  7. Filters With Inductance Cancellation Using Printed Circuit Board Transformers

    E-Print Network [OSTI]

    Neugebauer, Timothy C.

    Capacitor parasitic inductance often limits the high-frequency performance of filters for power applications. However, these limitations can be overcome through the use of specially-coupled magnetic windings that effectively ...

  8. Toroidal plasma enhanced CVD of diamond films

    SciTech Connect (OSTI)

    Zvanya, John, E-mail: zvanya03@students.rowan.edu; Cullen, Christopher, E-mail: cullen38@students.rowan.edu; Morris, Thomas, E-mail: morris1j@students.rowan.edu; Krchnavek, Robert R., E-mail: krchnavek@rowan.edu [Department of Electrical and Computer Engineering, Rowan University, Glassboro, New Jersey 08028 (United States); Holber, William, E-mail: b.holber@plasmability.com; Basnett, Andrew, E-mail: abasnett54@yahoo.com; Basnett, Robert, E-mail: b.basnett@plasmability.com [Plasmability LLC, Austin, Texas 78732 (United States); Hettinger, Jeffrey, E-mail: hettinger@rowan.edu [Department of Physics and Astronomy, Rowan University, Glassboro, New Jersey 08028 (United States)

    2014-09-01T23:59:59.000Z

    An inductively coupled toroidal plasma source is used as an alternative to microwave plasmas for chemical vapor deposition of diamond films. The source, operating at a frequency of 400 kHz, synthesizes diamond films from a mixture of argon, methane, and hydrogen. The toroidal design has been adapted to create a highly efficient environment for diamond film deposition: high gas temperature and a short distance from the sample to the plasma core. Using a toroidal plasma geometry operating in the medium frequency band allows for efficient (?90%) coupling of AC line power to the plasma and a scalable path to high-power and large-area operation. In test runs, the source generates a high flux of atomic hydrogen over a large area, which is favorable for diamond film growth. Using a deposition temperature of 900–1050?°C and a source to sample distance of 0.1–2.0?cm, diamond films are deposited onto silicon substrates. The results showed that the deposition rate of the diamond films could be controlled using the sample temperature and source to sample spacing. The results also show the films exhibit good-quality polycrystalline diamond as verified by Raman spectroscopy, x-ray diffraction, and scanning electron microscopy. The scanning electron microscopy and x-ray diffraction results show that the samples exhibit diamond (111) and diamond (022) crystallites. The Raman results show that the sp{sup 3} peak has a narrow spectral width (FWHM 12?±?0.5?cm{sup ?1}) and that negligible amounts of the sp{sup 2} band are present, indicating good-quality diamond films.

  9. High density plasma damage in InGaP/GaAs as AlGaAs/GaAs high electron mobility transistors

    SciTech Connect (OSTI)

    Lee, J.W.; Pearton, S.J. [Univ. of Florida, Gainesville, FL (United States). Dept. of Materials Science and Engineering; Ren, F.; Kopf, R.F.; Kuo, J.M. [Bell Labs., Murray Hill, NJ (United States). Lucent Technologies; Shul, R.J. [Sandia National Labs., Albuquerque, NM (United States); Constantine, C.; Johnson, D. [Plasma-Therm Inc., St. Petersburg, FL (United States)

    1998-11-01T23:59:59.000Z

    The introduction of plasma damage in InGaP/GaAs and AlGaAs/GaAs high electron mobility transistors (HEMTs) has been investigated using both inductively coupled plasma and electron cyclotron resonance Ar discharges. The saturated drain-source current is found to be decreased through introduction of compensating deep levels into the InGaP or AlGaAs donor layer. The degradation of device performance is a strong function of ion energy and ion flux, and an advantage of both high density plasma tools is that ion energy can be reduced by increasing the plasma density. Increasing process pressure and source power, and decreasing radio-frequency chuck power produce the lowest amounts of plasma damage in HEMTs.

  10. Progress in Induction Linacs

    SciTech Connect (OSTI)

    Caporaso, G J

    2000-09-27T23:59:59.000Z

    This presentation will be a broad survey of progress in induction technology over the past four years. Much work has been done on accelerators for hydrodynamic test radiography and other applications. Solid-state pulsers have been developed which can provide unprecedented flexibility and precision in pulse format and accelerating voltage for both ion and electron induction machines. Induction linacs can now be built which can operate with MHz repetition rates. Solid-state technology has also made possible the development of fast kickers for precision control of high current beams. New insulator technology has been developed which will improve conventional induction linacs in addition to enabling a new class of high gradient induction linacs.

  11. argon plasma atomic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    observed in a complex plasma are presented. The experiments are performed with an argon plasma which is produced under microgravity conditions using a capacitively-coupled rf...

  12. Hybrid-secondary uncluttered induction machine

    DOE Patents [OSTI]

    Hsu, John S. (Oak Ridge, TN)

    2001-01-01T23:59:59.000Z

    An uncluttered secondary induction machine (100) includes an uncluttered rotating transformer (66) which is mounted on the same shaft as the rotor (73) of the induction machine. Current in the rotor (73) is electrically connected to current in the rotor winding (67) of the transformer, which is not electrically connected to, but is magnetically coupled to, a stator secondary winding (40). The stator secondary winding (40) is alternately connected to an effective resistance (41), an AC source inverter (42) or a magnetic switch (43) to provide a cost effective slip-energy-controlled, adjustable speed, induction motor that operates over a wide speed range from below synchronous speed to above synchronous speed based on the AC line frequency fed to the stator.

  13. RF-Plasma Source Commissioning in Indian Negative Ion Facility

    SciTech Connect (OSTI)

    Singh, M. J.; Bandyopadhyay, M.; Yadava, Ratnakar; Chakraborty, A. K. [ITER- India, Institute for Plasma Research, A-29, Sector 25, GIDC, Gandhinagar, Gujrat (India); Bansal, G.; Gahlaut, A.; Soni, J.; Kumar, Sunil; Pandya, K.; Parmar, K. G.; Sonara, J. [Institute for Plasma Research, Bhat Gandhinagar, Gujrat (India); Kraus, W.; Heinemann, B.; Riedl, R.; Obermayer, S.; Martens, C.; Franzen, P.; Fantz, U. [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching (Germany)

    2011-09-26T23:59:59.000Z

    The Indian program of the RF based negative ion source has started off with the commissioning of ROBIN, the inductively coupled RF based negative ion source facility under establishment at Institute for Plasma research (IPR), India. The facility is being developed under a technology transfer agreement with IPP Garching. It consists of a single RF driver based beam source (BATMAN replica) coupled to a 100 kW, 1 MHz RF generator with a self excited oscillator, through a matching network, for plasma production and ion extraction and acceleration. The delivery of the RF generator and the RF plasma source without the accelerator, has enabled initiation of plasma production experiments. The recent experimental campaign has established the matching circuit parameters that result in plasma production with density in the range of 0.5-1x10{sup 18}/m{sup 3}, at operational gas pressures ranging between 0.4-1 Pa. Various configurations of the matching network have been experimented upon to obtain a stable operation of the set up for RF powers ranging between 25-85 kW and pulse lengths ranging between 4-20 s. It has been observed that the range of the parameters of the matching circuit, over which the frequency of the power supply is stable, is narrow and further experiments with increased number of turns in the coil are in the pipeline to see if the range can be widened. In this paper, the description of the experimental system and the commissioning data related to the optimisation of the various parameters of the matching network, to obtain stable plasma of required density, are presented and discussed.

  14. Role of plasma enhanced atomic layer deposition reactor wall conditions on radical and ion substrate fluxes

    SciTech Connect (OSTI)

    Sowa, Mark J., E-mail: msowa@ultratech.com [Ultratech/Cambridge NanoTech, 130 Turner Street, Building 2, Waltham, Massachusetts 02453 (United States)

    2014-01-15T23:59:59.000Z

    Chamber wall conditions, such as wall temperature and film deposits, have long been known to influence plasma source performance on thin film processing equipment. Plasma physical characteristics depend on conductive/insulating properties of chamber walls. Radical fluxes depend on plasma characteristics as well as wall recombination rates, which can be wall material and temperature dependent. Variations in substrate delivery of plasma generated species (radicals, ions, etc.) impact the resulting etch or deposition process resulting in process drift. Plasma enhanced atomic layer deposition is known to depend strongly on substrate radical flux, but film properties can be influenced by other plasma generated phenomena, such as ion bombardment. In this paper, the chamber wall conditions on a plasma enhanced atomic layer deposition process are investigated. The downstream oxygen radical and ion fluxes from an inductively coupled plasma source are indirectly monitored in temperature controlled (25–190?°C) stainless steel and quartz reactors over a range of oxygen flow rates. Etch rates of a photoresist coated quartz crystal microbalance are used to study the oxygen radical flux dependence on reactor characteristics. Plasma density estimates from Langmuir probe ion saturation current measurements are used to study the ion flux dependence on reactor characteristics. Reactor temperature was not found to impact radical and ion fluxes substantially. Radical and ion fluxes were higher for quartz walls compared to stainless steel walls over all oxygen flow rates considered. The radical flux to ion flux ratio is likely to be a critical parameter for the deposition of consistent film properties. Reactor wall material, gas flow rate/pressure, and distance from the plasma source all impact the radical to ion flux ratio. These results indicate maintaining chamber wall conditions will be important for delivering consistent results from plasma enhanced atomic layer deposition systems.

  15. Induction melter apparatus

    SciTech Connect (OSTI)

    Roach, Jay A [Idaho Falls, ID; Richardson, John G [Idaho Falls, ID; Raivo, Brian D [Idaho Falls, ID; Soelberg, Nicholas R [Idaho Falls, ID

    2008-06-17T23:59:59.000Z

    Apparatus and methods of operation are provided for a cold-crucible-induction melter for vitrifying waste wherein a single induction power supply may be used to effect a selected thermal distribution by independently energizing at least two inductors. Also, a bottom drain assembly may be heated by an inductor and may include an electrically resistive heater. The bottom drain assembly may be cooled to solidify molten material passing therethrough to prevent discharge of molten material therefrom. Configurations are provided wherein the induction flux skin depth substantially corresponds with the central longitudinal axis of the crucible. Further, the drain tube may be positioned within the induction flux skin depth in relation to material within the crucible or may be substantially aligned with a direction of flow of molten material within the crucible. An improved head design including four shells forming thermal radiation shields and at least two gas-cooled plenums is also disclosed.

  16. Linear induction accelerator

    DOE Patents [OSTI]

    Buttram, M.T.; Ginn, J.W.

    1988-06-21T23:59:59.000Z

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

  17. Control of power to an inductively heated part

    DOE Patents [OSTI]

    Adkins, Douglas R. (1620 Adelita Dr. NE., Albuquerque, NM 87112); Frost, Charles A. (1039 Red Oaks Loop NE., Albuquerque, NM 87122); Kahle, Philip M. (528 Longwood Loop NE., Rio Rancho, NM 87124); Kelley, J. Bruce (13200 Blue Corn Maiden Trail NE., Albuquerque, NM 87112); Stanton, Suzanne L. (2805 Palo Alto NE., Albuquerque, NM 87112)

    1997-01-01T23:59:59.000Z

    A process for induction hardening a part to a desired depth with an AC signal applied to the part from a closely coupled induction coil includes measuring the voltage of the AC signal at the coil and the current passing through the coil; and controlling the depth of hardening of the part from the measured voltage and current. The control system determines parameters of the part that are functions of applied voltage and current to the induction coil, and uses a neural network to control the application of the AC signal based on the detected functions for each part.

  18. Control of power to an inductively heated part

    DOE Patents [OSTI]

    Adkins, D.R.; Frost, C.A.; Kahle, P.M.; Kelley, J.B.; Stanton, S.L.

    1997-05-20T23:59:59.000Z

    A process for induction hardening a part to a desired depth with an AC signal applied to the part from a closely coupled induction coil includes measuring the voltage of the AC signal at the coil and the current passing through the coil; and controlling the depth of hardening of the part from the measured voltage and current. The control system determines parameters of the part that are functions of applied voltage and current to the induction coil, and uses a neural network to control the application of the AC signal based on the detected functions for each part. 6 figs.

  19. arc plasma method: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    for two types of plasma sources used cathodic-arc plasma source show the coupling efficiency of the plasma flow from the source to the drift Gilson, Erik 8 Computational study...

  20. Gravimagnetic shock waves in the anisotropic plasma

    E-Print Network [OSTI]

    Yu. G. Ignatyev; D. N. Gorokhov

    2011-01-01T23:59:59.000Z

    The relativistic magnetohydrodynamic equations for the anisotropic magnetoactive plasma are obtained and accurately integrated in the plane gravitational wave metrics. The dependence of the induction mechanism of the gravimagnetic shock waves on the degree of the magnetoactive plasma anisotropy is analyzed.

  1. Improving interface through surface modification by plasma polymerization, in carbon/graphite fiber reinforced polymeric composites

    SciTech Connect (OSTI)

    Dagli, N.G.

    1986-01-01T23:59:59.000Z

    Carbon/graphite fiber surfaces were modified by plasma polymerization. An inductively coupled electrodeless glow-discharge system was utilized to treat the surfaces with acrylonitrile or styrene at the established operating conditions. Critical surface erosion for wetting measured by the sessile drop method, of plasma treated pyrolytic graphite blocks, used as a model surface for carbon/graphite fibers, were lower than of untreated block. Contact angles on plasma polymers deposited on different substrates had similar values. Contact angle, measured by Wilhelmy balance method of water, on untreated Fortafil 3 carbon/graphite fiber was 55.1/sup 0/, whereas the commercially treated one was 43.7/sup 0/. Plasma treatments reduced the contact angle to 44.3/sup 0/ in An and 47.3/sup 0/ in styrene monomer cases. Thicknesses of plasma polymers deposited under the established optimum conditions, measured by ellipsometer, were 840 A for PPAN and 2192 A for PPST after one hour treatment. In conclusion, plasma treatments of carbon/graphite fibers are an effective alternative to existing methods for improving interfacial shear strengths and maintaining or improving the tensile strengths of the fibers.

  2. HIGH GRADIENT INDUCTION ACCELERATOR

    SciTech Connect (OSTI)

    Caporaso, G J; Sampayan, S; Chen, Y; Blackfield, D; Harris, J; Hawkins, S; Holmes, C; Krogh, M; Nelson, S; Nunnally, W; Paul, A; Poole, B; Rhodes, M; Sanders, D; Selenes, K; Sullivan, J; Wang, L; Watson, J

    2007-06-21T23:59:59.000Z

    A new type of compact induction accelerator is under development at the Lawrence Livermore National Laboratory that promises to increase the average accelerating gradient by at least an order of magnitude over that of existing induction machines. The machine is based on the use of high gradient vacuum insulators, advanced dielectric materials and switches and is stimulated by the desire for compact flash x-ray radiography sources. Research describing an extreme variant of this technology aimed at proton therapy for cancer will be described. Progress in applying this technology to several applications will be reviewed.

  3. On Automating Inductive and Non-Inductive Termination Methods

    E-Print Network [OSTI]

    Kamareddine, Fairouz

    On Automating Inductive and Non-Inductive Termination Methods Fairouz Kamareddine and Francois of the function which satis es a notion of terminal prop- erty and then verifying that this construction processPre can only deal with the termination proofs that are inductive. There are however many functions

  4. Resonant-cavity antenna for plasma heating

    DOE Patents [OSTI]

    Perkins, Jr., Francis W. (Princeton, NJ); Chiu, Shiu-Chu (San Diego, CA); Parks, Paul (San Diego, CA); Rawls, John M. (Del Mar, CA)

    1987-01-01T23:59:59.000Z

    Disclosed is a resonant coil cavity wave launcher for energizing a plasma immersed in a magnetic field. Energization includes launching fast Alfven waves to excite ion cyclotron frequency resonances in the plasma. The cavity includes inductive and capacitive reactive members spaced no further than one-quarter wavelength from a first wall confinement chamber of the plasma. The cavity wave launcher is energized by connection to a waveguide or transmission line carrying forward power from a remote radio frequency energy source.

  5. Low inductance connector assembly

    DOE Patents [OSTI]

    Holbrook, Meghan Ann; Carlson, Douglas S

    2013-07-09T23:59:59.000Z

    A busbar connector assembly for coupling first and second terminals on a two-terminal device to first and second contacts on a power module is provided. The first terminal resides proximate the first contact and the second terminal resides proximate the second contact. The assembly comprises a first bridge having a first end configured to be electrically coupled to the first terminal, and a second end configured to be electrically coupled to the second contact, and a second bridge substantially overlapping the first bridge and having a first end electrically coupled to the first contact, and a second end electrically coupled to the second terminal.

  6. Properties of On-Chip Inductive Current Loops Andrey V. Mezhiba and Eby G. Friedman

    E-Print Network [OSTI]

    Friedman, Eby G.

    dimensions. This linear behavior can be used to simplify the inductance extraction and circuit analysis the interconnects are tightly coupled, the current return path is typically not known prior to the circuit analysis@ece.rochester.edu, friedman@ece.rochester.edu Abstract The variation of inductance with circuit length is investigated

  7. Progress on a New RF Plasma Generator a

    E-Print Network [OSTI]

    source goal: produce high-recycling, strongly coupled PMI regime, guided by ITER divertor plasma Divertor Plasma Heat & Particle Fluxes ITER divertor channel What source plasma parameters are required? High-recycling plasmas led to new understanding · SOLPS (B2-Eirene) (Jülich; Garching; U. Paris) ­ Models for plasma

  8. Experimental investigations of electron density and ion energy distributions in dual-frequency capacitively coupled plasmas for Ar/CF{sub 4} and Ar/O{sub 2}/CF{sub 4} discharges

    SciTech Connect (OSTI)

    Liu, Jia; Liu, Yong-Xin; Gao, Fei; Wang, You-Nian, E-mail: ynwang@dlut.edu.cn [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Bi, Zhen-Hua [School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China)

    2014-01-07T23:59:59.000Z

    The electron density and ion energy distribution (IED) are investigated in low-pressure dual-frequency capacitively coupled Ar/CF{sub 4} (90%/10%) and Ar/O{sub 2}/CF{sub 4} (80%/10%/10%) plasmas. The relations between controllable parameters, such as high-frequency (HF) power, low-frequency (LF) power and gas pressure, and plasma parameters, such as electron density and IEDs, are studied in detail by utilizing a floating hairpin probe and an energy resolved quadrupole mass spectrometer, respectively. In our experiment, the electron density is mainly determined by the HF power and slightly influenced by the LF power. With increasing gas pressure, the electron density first goes up rapidly to a maximum value and then decreases at various HF and LF powers. The HF power also plays a considerable role in affecting the IEDs under certain conditions and the ion energy independently controlled by the LF source is discussed here. For clarity, some numerical results obtained from a two-dimensional fluid model are presented.

  9. Harmonic control of multiple-stator induction machines for voltage regulation

    E-Print Network [OSTI]

    Holloway, Jack Wade, 1980-

    2004-01-01T23:59:59.000Z

    Small, one to a few horsepower, three-phase induction machines with three sets of electrically-isolated, magnetically-coupled stator winding circuits are described. A voltage inverter is developed and used to drive one set ...

  10. Porous materials by design. Plasma oxidation of hydrocarbon templates in polysilsesquioxanes

    SciTech Connect (OSTI)

    Loy, D.A.; Buss, R.J.; Assink, R.A. (Sandia National Labs., Albuquerque, NM (United States)); Shea, K.J.; Oviatt, H. (California Univ., Irvine, CA (United States). Dept. of Chemistry)

    1992-01-01T23:59:59.000Z

    Arylene- and alkylene-bridged polysilsesquioxanes were prepared by sol-gel processing of bis(triethoxysilyl)-aryl monomers and decyl monomer. The arylene polysilsesquioxanes were porous materials with surface areas as high as 830 m[sup 2]/g (BET). Treatment with an inductively coupled oxygen plasma resulted in the near quantitative removal of the arylene bridging groups and a coarsening of the pore structure. Solid state [sup 29]Si NMR was used to confirm the conversion of the sesquioxane silicons (T) to silica (Q). The decylene-bridged polysilsesquioxane was a non-porous material. Oxygen plasma treatment afforded a silica gel with a surface area of 294 m[sup 2]/g and a mean pore diameter of 46 [Angstrom]. The porosity in the silica gel appears to arise entirely from the oxidation of the 1,10-decylene spacer.

  11. Porous materials by design. Plasma oxidation of hydrocarbon templates in polysilsesquioxanes

    SciTech Connect (OSTI)

    Loy, D.A.; Buss, R.J.; Assink, R.A. [Sandia National Labs., Albuquerque, NM (United States); Shea, K.J.; Oviatt, H. [California Univ., Irvine, CA (United States). Dept. of Chemistry

    1992-12-31T23:59:59.000Z

    Arylene- and alkylene-bridged polysilsesquioxanes were prepared by sol-gel processing of bis(triethoxysilyl)-aryl monomers and decyl monomer. The arylene polysilsesquioxanes were porous materials with surface areas as high as 830 m{sup 2}/g (BET). Treatment with an inductively coupled oxygen plasma resulted in the near quantitative removal of the arylene bridging groups and a coarsening of the pore structure. Solid state {sup 29}Si NMR was used to confirm the conversion of the sesquioxane silicons (T) to silica (Q). The decylene-bridged polysilsesquioxane was a non-porous material. Oxygen plasma treatment afforded a silica gel with a surface area of 294 m{sup 2}/g and a mean pore diameter of 46 {Angstrom}. The porosity in the silica gel appears to arise entirely from the oxidation of the 1,10-decylene spacer.

  12. Engineering of porosity in amorphous materials. Plasma oxidation of hydrocarbon templates in polysilsesquioxanes

    SciTech Connect (OSTI)

    Loy, D.A.; Buss, R.J.; Assink, R.A. [Sandia National Labs., Albuquerque, NM (United States); Shea, K.J.; Oviatt, H. [Univ. of California, Irvine, CA (United States)

    1994-12-31T23:59:59.000Z

    Arylene- and alkylene-bridged polysilsesquioxanes were prepared by sol-gel processing of bis(triethoxysilyl)-arylene monomers 1--4, and alkylene monomers 5--9. The arylene polysilsesquioxanes were porous materials with surface areas as high as 830 m{sup 2}/g (BET). Treatment with an inductively coupled oxygen plasma resulted in the near quantitative removal of the arylene bridging groups and a coarsening of the pore structure. Solid state {sup 29}Si NMR was used to confirm the conversion of the sesquioxane silicons (T) to silica (Q). The alkylene-bridged polysilsesquioxanes were non-porous. Oxygen plasma treatment afforded silica gels with mesoporosity. The porosity in the silica gels appears to arise entirely from the oxidation of the alkylene spacers.

  13. Porous materials by design. Plasma oxidation of hydrocarbon templates in polysilsesquioxanes

    SciTech Connect (OSTI)

    Loy, D.A.; Buss, R.J.; Assink, R.A. [Sandia National Laboratories, Albuquerque, NM (United States); Shea, K.J.; Oviatt, H. [Univ. of California, Irvine, CA (United States)

    1993-12-31T23:59:59.000Z

    Arylene- and alkylene-bridged polysilsesquioxanes were prepared by sol-gel processing of bis (triethoxysilyl)-aryl monomers 1-4 and decyl monomer 5. The arylene polysilsesquioxanes were porous materials with surface areas as high as 830 m{sup 2}/g (BET). Treatment with an inductively coupled oxygen plasma resulted in the near quantitative removal of the arylene bridging groups and a coarsening of the pore structure. Solid state {sup 29}Si NMR was used to confirm the conversion of the sesquioxane silicons (T) to silica (Q). The decylene-bridged polysilsesquinoxane was non-porous materials. Oxygen plasma treatment afforded a silica gel with a surface area of 294 m{sup 2}/g and a mean pore diameter of 46 {angstrom}. The porosity in the silica gel appears to arise entirely from the oxidation of the 1,10-decylene spacer.

  14. Low inductance busbar assembly

    DOE Patents [OSTI]

    Holbrook, Meghan Ann (Manhattan Beach, CA)

    2010-09-21T23:59:59.000Z

    A busbar assembly for electrically coupling first and second busbars to first and second contacts, respectively, on a power module is provided. The assembly comprises a first terminal integrally formed with the first busbar, a second terminal integrally formed with the second busbar and overlapping the first terminal, a first bridge electrode having a first tab electrically coupled to the first terminal and overlapping the first and second terminals, and a second tab electrically coupled to the first contact, a second bridge electrode having a third tab electrically coupled to the second terminal, and overlapping the first and second terminals and the first tab, and a fourth tab electrically coupled to the second contact, and a fastener configured to couple the first tab to the first terminal, and the third tab to the second terminal.

  15. Effet de la temprature et du temps de frittage sur les proprits du ferrite NiCuZn :Co fritt avec le procd Spark Plasma Sintering ( SPS ) et ralisation d'une inductance intgrs.

    E-Print Network [OSTI]

    Boyer, Edmond

    Effet de la température et du temps de frittage sur les propriétés du ferrite NiCuZn :Co fritté.zehani@satie.ens-cachan.fr _______________________________________________________________________________________________ Résumé : Le frittage du ferrite spinelle NiCuZn par le procédé Spark Plasma Sintering a été étudié pour structurales, diélectrique et magnétique pour ce ferrite ont été étudiées pour différentes valeurs de la

  16. Plasma Performance Improvement with Lithium-Coated Plasma-Facing Components in NSTX

    SciTech Connect (OSTI)

    Kaita, R; Kugel, H; Bell, M G; Bell, R; Boedo, J; Bush, C; Ellis, R; Gates, D; Gerhardt, S; Gray, T; Kallman, J; Kaye, S; LeBlanc, B; Majeski, R; Maingi, R; Mansfield, D; Menard, J; Mueller, D; Ono, M; Paul, S; Raman, R; Roquemore, A L; Ross, P W; Sabbagh, S; Schneider, H; Skinner, S H; Soukhanovskii, V; Stevenson, T; Stotler, D; Timberlake, J; Zakharov, L; Ahn, J; Allain, J P; Wampler, W R

    2009-01-08T23:59:59.000Z

    Lithium as a plasma-facing material has many attractive features, including a reduction in the recycling of hydrogenic species and the potential for withstanding high heat and neutron fluxes in fusion reactors. Recent NSTX experiments have shown, for the first time, significant and recurring benefits of lithium coatings on plasma-facing components (PFC's) to the performance of divertor plasmas in both L- and H- mode confinement regimes heated by high-power neutral beams. They included decreases in the plasma density and inductive flux consumption, and increases in the electron temperature, ion temperature, energy confinement time, and DD neutron rate. Extended periods of MHD quiescence were also achieved, and measurements of the visible emission from the lower divertor showed a reduction in the deuterium, carbon, and oxygen line emission. Other salient results with lithium evaporation included a broadening of the electron temperature profile, and changes in edge density gradients that benefited electron Bernstein wave coupling. There was also a reduction in ELM frequency and amplitude, followed by a period of complete ELM suppression. In general, it was observed that both the best and the average confinement occurred after lithium deposition and that the increase in WMHD occurs mostly through an increase in We. In addition, a liquid lithium divertor (LLD) is being installed on NSTX this year. As the first fully-toroidal liquid metal divertor target, experiments with the LLD can provide insight into the behavior of metallic ITER PFC's should they liquefy during high-power divertor tokamak operations. The NSTX lithium coating and LLD experiments are important near-term steps in demonstrating the potential of liquid lithium as a solution to the first-wall problem for both magnetic and inertial fusion reactors.

  17. Plasma Performance Improvement with Lithium-Coated Plasma-Facing Components in NSTX

    SciTech Connect (OSTI)

    Kaita, R., et. al.

    2008-09-29T23:59:59.000Z

    Lithium as a plasma-facing material has many attractive features, including a reduction in the recycling of hydrogenic species and the potential for withstanding high heat and neutron fluxes in fusion reactors. Recent NSTX experiments have shown, for the first time, significant and recurring benefits of lithium coatings on plasma-facing components (PFC's) to the performance of divertor plasmas in both L- and H- mode confinement regimes heated by high-power neutral beams. They included decreases in the plasma density and inductive flux consumption, and increases in the electron temperature, ion temperature, energy confinement time, and DD neutron rate. Extended periods of MHD quiescence were also achieved, and measurements of the visible emission from the lower divertor showed a reduction in the deuterium, carbon, and oxygen line emission. Other salient results with lithium evaporation included a broadening of the electron temperature profile, and changes in edge density gradients that benefited electron Bernstein wave coupling. There was also a reduction in ELM frequency and amplitude, followed by a period of complete ELM suppression. In general, it was observed that both the best and the average confinement occurred after lithium deposition and that the increase in WMHD occurs mostly through an increase in We. In addition, a liquid lithium divertor (LLD) is being installed on NSTX this year. As the first fully-toroidal liquid metal divertor target, experiments with the LLD can provide insight into the behavior of metallic ITER PFC's should they liquefy during high-power divertor tokamak operations. The NSTX lithium coating and LLD experiments are important near-term steps in demonstrating the potential of liquid lithium as a solution to the first-wall problem for both magnetic and inertial fusion reactors.

  18. Superconducting inductive displacement detection of a microcantilever

    SciTech Connect (OSTI)

    Vinante, A., E-mail: anvinante@fbk.eu [Istituto di Fotonica e Nanotecnologie, CNR - Fondazione Bruno Kessler, I-38123 Povo, Trento (Italy)

    2014-07-21T23:59:59.000Z

    We demonstrate a superconducting inductive technique to measure the displacement of a micromechanical resonator. In our scheme, a type I superconducting microsphere is attached to the free end of a microcantilever and approached to the loop of a dc Superconducting Quantum Interference Device (SQUID) microsusceptometer. A local magnetic field as low as 100??T, generated by a field coil concentric to the SQUID, enables detection of the cantilever thermomechanical noise at 4.2?K. The magnetomechanical coupling and the magnetic spring are in good agreement with image method calculations assuming pure Meissner effect. These measurements are relevant to recent proposals of quantum magnetomechanics experiments based on levitating superconducting microparticles.

  19. MARINE ECOLOGY PROGRESS SERIES Mar Ecol Prog Ser

    E-Print Network [OSTI]

    Miami, University of

    determined in 0-group fish otoliths using laser ablation-inductively coupled plasma mass spectrometry. Two

  20. Magnetite composition in Ni-Cu-PGE deposits worldwide: application to mineral exploration

    E-Print Network [OSTI]

    = 61) by laser ablation-inductively coupled plasma- mass spectrometry. The composition of all primary

  1. Formation of Metal in the CH Chondrites ALH 85085 and PCA ANDREW J. CAMPBELL* AND MUNIR HUMAYUN

    E-Print Network [OSTI]

    Campbell, Andrew

    by laser ablation inductively coupled plasma mass spectrometry. Those metal grains that are zoned in Ni

  2. Partitioning behavior at 9 GPa in the FeS system and implications for planetary evolution

    E-Print Network [OSTI]

    Mcdonough, William F.

    of the experimental charges by in situ laser ablation inductively coupled plasma mass spectrometry enabled

  3. Surface and subsurface seawater temperature reconstruction using Mg/Ca microanalysis of planktonic foraminifera Globigerinoides ruber,

    E-Print Network [OSTI]

    ] Laser­ablation inductively coupled plasma­mass spectrometry microanalyses of Mg/Ca across individual

  4. Summary of current research interests The use of zinc in medicine was mentioned in Egyptian papyri from 2000 BC,

    E-Print Network [OSTI]

    Saunders, Mark

    , fluorescent microscopy, synchrotron X-ray fluorescence and laser ablation inductively coupled plasma mass

  5. Compositions of Group IVB Iron Meteorites and Their Parent ANDREW J. CAMPBELL*,1

    E-Print Network [OSTI]

    Campbell, Andrew

    , and Warburton Range have been measured by laser ablation inductively coupled plasma mass spectrometry. The data

  6. 1 Managed by UT-Battelle for the Department of Energy Presentation_name

    E-Print Network [OSTI]

    fluorescence spectroscopy, liquid scintillation counting, inductive-coupled plasma mass spectrometry (ICP

  7. Implantation, flux and recoil distributions for plasma species impinging on tokamak divertor materials

    E-Print Network [OSTI]

    Moshman, Nathan David

    2009-01-01T23:59:59.000Z

    Plasma Species Impinging on Tokamak Divertor Materials. APlasma Species Impinging on Tokamak Divertor Materials. byquantities needed to couple tokamak edge plasma to coolant

  8. Electron Bernstein wave current drive modeling in toroidal plasma confinement

    E-Print Network [OSTI]

    Decker, Joan, 1977-

    2005-01-01T23:59:59.000Z

    The steady-state confinement of tokamak plasmas in a fusion reactor requires non-inductively driven toroidal currents. Radio frequency waves in the electron cyclotron (EC) range of frequencies can drive localized currents ...

  9. Effect of H2 on the etch profile of InPInGaAsP alloys in Cl2 ArH2 inductively coupled plasma reactive ion etching chemistries

    E-Print Network [OSTI]

    Rommel, Sean

    extensively. Dry-etching studies of InP have pursued two general chemistries: methane-based etching and Cl2-based etching. Reactive ion etching studies typically pursued a CH4 /H2 etch in conjunction Cl2 /Ar in a chemically assisted ion-beam etching chamber was established by Youtsey et al.7

  10. Standard practice for the determination of 237Np, 232Th, 235U and 238U in urine by inductively coupled plasma-Mass spectrometry (ICP-MS) and gamma ray spectrometry.

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2005-01-01T23:59:59.000Z

    1.1 This practice covers the separation and preconcentration of neptunium-237 (237Np), thorium-232 (232Th), uranium-235 (235U) and uranium-238 (238U) from urine followed by quantitation using ICP-MS. 1.2 This practice can be used to support routine bioassay programs. The minimum detectable concentrations (MDC) for this method, taking the preconcentration factor into account, are approximately 1E-2Bq for 237Np (0.38ng), 2E-6Bq for 232Th (0.50ng), 4E-5Bq for 235U (0.50ng) and 6E-6Bq for 238U (0.48ng). 1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  11. Comparison of analytical methods for percent phosphorous determination in electroless nickel plate. [UCC-ND alkalimetric method; UCC-ND Inductively Coupled Plasma (ICP) method; ASTM-E39 gravimetric method; development colorimetric method; independent colorimetric method

    SciTech Connect (OSTI)

    Owens, W.W.; Sullivan, H.H.

    1982-01-01T23:59:59.000Z

    Electroless nicke-plate characteristics are substantially influenced by percent phosphorous concentrations. Available ASTM analytical methods are designed for phosphorous concentrations of less than one percent compared to the 4.0 to 20.0% concentrations common in electroless nickel plate. A variety of analytical adaptations are applied through the industry resulting in poor data continuity. This paper presents a statistical comparison of five analytical methods and recommends accurate and precise procedures for use in percent phosphorous determinations in electroless nickel plate. 2 figures, 1 table.

  12. Coulomb scattering in plasma revised

    E-Print Network [OSTI]

    S. Gordienko; D. V. Fisher; J. Meyer-ter-Vehn

    2003-05-13T23:59:59.000Z

    A closed expression for the momentum evolution of a test particle in weakly-coupled plasma is derived, starting from quantum many particle theory. The particle scatters from charge fluctuations in the plasma rather than in a sequence of independent binary collisions. Contrary to general belief, Bohr's (rather than Bethe's) Coulomb logarithm is the relevant one in most plasma applications. A power-law tail in the distribution function is confirmed by molecular dynamics simulation.

  13. Low inductance gas switching.

    SciTech Connect (OSTI)

    Chavez, Ray; Harjes, Henry Charles III; Wallace, Zachariah; Elizondo, Juan E.

    2007-10-01T23:59:59.000Z

    The laser trigger switch (LTS) is a key component in ZR-type pulsed power systems. In ZR, the pulse rise time through the LTS is > 200 ns and additional stages of pulse compression are required to achieve the desired <100 ns rise time. The inductance of the LTS ({approx}500nH) in large part determines the energy transfer time through the switch and there is much to be gained in improving system performance and reducing system costs by reducing this inductance. The current path through the cascade section of the ZR LTS is at a diameter of {approx} 6-inches which is certainly not optimal from an inductance point of view. The LTS connects components of much greater diameter (typically 4-5 feet). In this LDRD the viability of switch concepts in which the diameter of cascade section is greatly increased have been investigated. The key technical question to be answered was, will the desired multi-channel behavior be maintained in a cascade section of larger diameter. This LDRD proceeded in 2 distinct phases. The original plan for the LDRD was to develop a promising switch concept and then design, build, and test a moderate scale switch which would demonstrate the key features of the concept. In phase I, a switch concept which meet all electrical design criteria and had a calculated inductance of 150 nH was developed. A 1.5 MV test switch was designed and fabrication was initiated. The LDRD was then redirected due to budgetary concerns. The fabrication of the switch was halted and the focus of the LDRD was shifted to small scale experiments designed to answer the key technical question concerning multi-channel behavior. In phase II, the Multi-channel switch test bed (MCST) was designed and constructed. The purpose of MCST was to provide a versatile, fast turn around facility for the study the multi-channel electrical breakdown behavior of a ZR type cascade switch gap in a parameter space near that of a ZR LTS. Parameter scans on source impedance, gap tilt, gap spacing and electrode diameter were conducted.

  14. Magnetic field distribution in the plasma flow generated by a plasma focus discharge

    SciTech Connect (OSTI)

    Mitrofanov, K. N., E-mail: mitrofan@triniti.ru [Troitsk Institute for Innovaiton and Fusion Research (Russian Federation); Krauz, V. I., E-mail: krauz_vi@nrcki.ru; Myalton, V. V.; Velikhov, E. P.; Vinogradov, V. P.; Vinogradova, Yu. V. [National Research Centre Kurchatov Institute (Russian Federation)

    2014-11-15T23:59:59.000Z

    The magnetic field in the plasma jet propagating from the plasma pinch region along the axis of the chamber in a megajoule PF-3 plasma focus facility is studied. The dynamics of plasma with a trapped magnetic flow is analyzed. The spatial sizes of the plasma jet region in which the magnetic field concentrates are determined in the radial and axial directions. The magnetic field configuration in the plasma jet is investigated: the radial distribution of the azimuthal component of the magnetic field inside the jet is determined. It is shown that the magnetic induction vector at a given point in space can change its direction during the plasma flight. Conclusions regarding the symmetry of the plasma flow propagation relative to the chamber axis are drawn.

  15. Accounting & Finance (BAcc) Induction 2014

    E-Print Network [OSTI]

    Glasgow, University of

    Accounting & Finance (BAcc) Induction 2014 Monday 15 September 2014 Induction Programme: 0945] Welcome from the Business School and Accounting & Finance 1000 The Accountancy Degrees 1015 Programme & 3 on Level 4 Accounting & Finance Bldg Tuesday 16 September 2014 Advising Session Lunch (provided

  16. Applied inductive learning Louis Wehenkel

    E-Print Network [OSTI]

    Wehenkel, Louis

    problems 20 2.3.1 Classes 20 2.3.2 Types of classi cation problems 20 2.3.3 Learning and test sets 21 2Applied inductive learning Louis Wehenkel University of Li`ege Faculty of Applied Sciences Course;#12;APPLIED INDUCTIVE LEARNING COURSE NOTES : OCTOBER 2000 LOUIS A. WEHENKEL University of Li#12;ege

  17. Applied inductive learning Louis Wehenkel

    E-Print Network [OSTI]

    Wehenkel, Louis

    .3.2 Types of classification problems 20 2.3.3 Learning and test sets 21 2.3.4 Decision or classificationApplied inductive learning Louis Wehenkel University of Liâ??ege Faculty of Applied Sciences Courseâ??e'' #12; #12; APPLIED INDUCTIVE LEARNING COURSE NOTES : OCTOBER 2000 LOUIS A. WEHENKEL University of Li

  18. Induction Linac Pulsers

    SciTech Connect (OSTI)

    Faltens, Andris

    2011-01-07T23:59:59.000Z

    The pulsers used in most of the induction linacs evolved from the very large body of work that was done in the U.S. and Great Britain during the development of the pulsed magnetron for radar. The radar modulators started at {approx}100 kW and reached >10 MW by 1945. A typical pulse length was 1 {mu}s at a repetition rate of 1,000 pps. A very comprehensive account of the modulator development is Pulse Generators by Lebacqz and Glasoe, one of the Radiation Laboratory Series. There are many permutations of possible modulators, two of the choices being tube type and line type. In earlier notes I wrote that technically the vacuum tube pulser met all of our induction linac needs, in the sense that a number of tubes, in series and parallel if required, could produce our pulses, regulate their voltage, be useable in feed-forward correctors, and provide a low source impedance. At a lower speed, an FET array is similar, and we have obtained and tested a large array capable of >10 MW switching. A modulator with an electronically controlled output only needs a capacitor for energy storage and in a switched mode can transfer the energy from the capacitor to the load at high efficiency. Driving a full size Astron induction core and a simulated resistive 'beam load' we achieved >50% efficiency. These electronically controlled output pulses can produce the pulses we desire but are not used because of their high cost. The second choice, the line type pulser, visually comprises a closing switch and a distributed or a lumped element transmission line. The typical switch cannot open or stop conducting after the desired pulse has been produced, and consequently all of the initially stored energy is dissipated. This approximately halves the efficiency, and the original cost estimating program LIACEP used this factor of two, even though our circuits are usually worse, and even though our inveterate optimists often omit it. The 'missing' energy is that which is reflected back into the line from mismatches, the energy left in the accelerator module's capacitance, the energy lost in the switch during switching and during the pulse, and the energy lost in the pulse line charging circuit. For example, a simple resistor-limited power supply dissipates as much energy as it delivers to the pulse forming line, giving a factor if two by itself, therefore efficiency requires a more complicated charging system.

  19. Borehole induction coil transmitter

    DOE Patents [OSTI]

    Holladay, Gale (Livermore, CA); Wilt, Michael J. (Walnut Creek, CA)

    2002-01-01T23:59:59.000Z

    A borehole induction coil transmitter which is a part of a cross-borehole electromagnetic field system that is used for underground imaging applications. The transmitter consists of four major parts: 1) a wound ferrite or mu-metal core, 2) an array of tuning capacitors, 3) a current driver circuit board, and 4) a flux monitor. The core is wound with several hundred turns of wire and connected in series with the capacitor array, to produce a tuned coil. This tuned coil uses internal circuitry to generate sinusoidal signals that are transmitted through the earth to a receiver coil in another borehole. The transmitter can operate at frequencies from 1-200 kHz and supplies sufficient power to permit the field system to operate in boreholes separated by up to 400 meters.

  20. Plasma instrumentation for fusion power reactor control

    SciTech Connect (OSTI)

    Sager, G.T.; Bauer, J.F.; Maya, I.; Miley, G.H.

    1985-07-01T23:59:59.000Z

    Feedback control will be implemented in fusion power reactors to guard against unpredicted behavior of the plant and to assure desirable operation. In this study, plasma state feedback requirements for plasma control by systems strongly coupled to the plasma (magnet sets, RF, and neutral beam heating systems, and refueling systems) are estimated. Generic considerations regarding the impact of the power reactor environment on plasma instrumentation are outlined. Solutions are proposed to minimize the impact of the power reactor environment on plasma instrumentation. Key plasma diagnostics are evaluated with respect to their potential for upgrade and implementation as power reactor instruments.

  1. Plasma flow switch experiment on Procyon

    SciTech Connect (OSTI)

    Benage, J.F. Jr.; Bowers, R.; Peterson, D. [and others

    1995-09-01T23:59:59.000Z

    This report presents the results obtained from a series of plasma flow switch experiments done on the Procyon explosive pulse power generator. These experiments involved switching into a fixed inductance dummy load and also into a dynamic implosion load. The results indicated that the switch did fairly well at switching current into the load, but the results for the implosion are more ambiguous. The results are compared to calculations and the implications for future plasma flow switch work are discussed.

  2. Plasma generating apparatus for large area plasma processing

    DOE Patents [OSTI]

    Tsai, C.C.; Gorbatkin, S.M.; Berry, L.A.

    1991-07-16T23:59:59.000Z

    A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm[sup 2]. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity. 3 figures.

  3. Plasma generating apparatus for large area plasma processing

    DOE Patents [OSTI]

    Tsai, Chin-Chi (Oak Ridge, TN); Gorbatkin, Steven M. (Oak Ridge, TN); Berry, Lee A. (Oak Ridge, TN)

    1991-01-01T23:59:59.000Z

    A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm.sup.2. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity.

  4. Surface kinetics and plasma equipment model for Si etching by fluorocarbon plasmas

    E-Print Network [OSTI]

    Kushner, Mark

    Surface kinetics and plasma equipment model for Si etching by fluorocarbon plasmas Da Zhanga of fluorocarbon radicals on the reactor walls, polymer erosion rates and F atom diffusion through the polymer during Si etching using fluorocarbon gases in an induc- tively coupled plasma ICP reactor.4 They observed

  5. Loop-to-loop coupling.

    SciTech Connect (OSTI)

    Warne, Larry Kevin; Lucero, Larry Martin; Langston, William L.; Salazar, Robert Austin; Coleman, Phillip Dale; Basilio, Lorena I.; Bacon, Larry Donald

    2012-05-01T23:59:59.000Z

    This report estimates inductively-coupled energy to a low-impedance load in a loop-to-loop arrangement. Both analytical models and full-wave numerical simulations are used and the resulting fields, coupled powers and energies are compared. The energies are simply estimated from the coupled powers through approximations to the energy theorem. The transmitter loop is taken to be either a circular geometry or a rectangular-loop (stripline-type) geometry that was used in an experimental setup. Simple magnetic field models are constructed and used to estimate the mutual inductance to the receiving loop, which is taken to be circular with one or several turns. Circuit elements are estimated and used to determine the coupled current and power (an equivalent antenna picture is also given). These results are compared to an electromagnetic simulation of the transmitter geometry. Simple approximate relations are also given to estimate coupled energy from the power. The effect of additional loads in the form of attached leads, forming transmission lines, are considered. The results are summarized in a set of susceptibility-type curves. Finally, we also consider drives to the cables themselves and the resulting common-to-differential mode currents in the load.

  6. Solenoid-free Plasma Startup in NSTX using Coaxial Helicity Injection

    SciTech Connect (OSTI)

    Roger Raman; Thomas R. Jarboe; Michael G. Bell; Dennis Mueller; Brian A. Nelson; Benoit LeBlanc; Charles Bush; Masayoshi Nagata; Ted Biewer

    2005-01-03T23:59:59.000Z

    The favorable properties of the Spherical Torus (ST) arise from its very small aspect ratio. However, small aspect ratio devices have very restricted space for a substantial central solenoid. Thus methods for initiating the plasma current without relying on induction from a central solenoid are essential for the viability of the ST concept. Coaxial Helicity Injection (CHI) is a promising candidate for solenoid-free plasma startup in a ST. Recent experiments on the HIT-II ST at the University of Washington, have demonstrated the capability of a new method, referred to as transient CHI, to produce a high quality, closed-flux equilibrium that has then been coupled to induction, with a reduced requirement for transformer flux [R. Raman, T.R. Jarboe, B.A. Nelson, et al., Phys. Rev. Lett. 90 (February 2003) 075005-1]. An initial test of this method on the National Spherical Torus Experiment (NSTX) has produced about 140 kA of toroidal current. Modifications are now underway to improve capability for transient CHI in NSTX.

  7. argon inductively coupled: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The elements are listed in Table 1. These elements can also be determined in uranyl nitrate hexahydrate (UNH), uranium hexafluoride (UF6), triuranium octoxide (U3O8) and...

  8. Nonlinear effects in inductively coupled plasmasa... A. I. Smolyakovb)

    E-Print Network [OSTI]

    Smolyakov, Andrei

    at the second harmonic and mean ponderomotive potential as well as generation of the electric current the particle thermal velocity becomes com- parable with the wave phase velocity, the resonant wave­ particle to the wave period, so that the resonant condi- tion is kvth vth / , where vth is the particle thermal ve

  9. Apparatus and method for reducing inductive coupling between levitation and

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumni Alumni PARC/I-CARESAnalysisAntibodyScience|Contract

  10. Operating an induction melter apparatus

    DOE Patents [OSTI]

    Roach, Jay A.; Richardson, John G.; Raivo, Brian D.; Soelberg, Nicholas R.

    2006-01-31T23:59:59.000Z

    Apparatus and methods of operation are provided for a cold-crucible-induction melter for vitrifying waste wherein a single induction power supply may be used to effect a selected thermal distribution by independently energizing at least two inductors. Also, a bottom drain assembly may be heated by an inductor and may include an electrically resistive heater. The bottom drain assembly may be cooled to solidify molten material passing therethrough to prevent discharge of molten material therefrom. Configurations are provided wherein the induction flux skin depth substantially corresponds with the central longitudinal axis of the crucible. Further, the drain tube may be positioned within the induction flux skin depth in relation to material within the crucible or may be substantially aligned with a direction of flow of molten material within the crucible. An improved head design including four shells forming thermal radiation shields and at least two gas-cooled plenums is also disclosed.

  11. The acquisition of inductive constraints

    E-Print Network [OSTI]

    Kemp, Charles, Ph. D. Massachusetts Institute of Technology

    2008-01-01T23:59:59.000Z

    Human learners routinely make inductive inferences, or inferences that go beyond the data they have observed. Inferences like these must be supported by constraints, some of which are innate, although others are almost ...

  12. Noise performance of magneto-inductive cables

    SciTech Connect (OSTI)

    Wiltshire, M. C. K., E-mail: michael.wiltshire@imperial.ac.uk; Syms, R. R. A. [Optical and Semiconductor Devices Group, Department of Electrical and Electronic Engineering, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom)

    2014-07-21T23:59:59.000Z

    Magneto-inductive (MI) waveguides are metamaterial structures based on periodic arrangements of inductively coupled resonant magnetic elements. They are of interest for power transfer, communications and sensing, and can be realised in a flexible cable format. Signal-to-noise ratio is extremely important in applications involving signals. Here, we present the first experimental measurements of the noise performance of metamaterial cables. We focus on an application involving radiofrequency signal transmission in internal magnetic resonance imaging (MRI), where the subdivision of the metamaterial cable provides intrinsic patient safety. We consider MI cables suitable for use at 300 MHz during {sup 1}H MRI at 7 T, and find noise figures of 2.3–2.8?dB/m, together with losses of 3.0–3.9?dB/m, in good agreement with model calculations. These values are high compared to conventional cables, but become acceptable when (as here) the environment precludes the use of continuous conductors. To understand this behaviour, we present arguments for the fundamental performance limitations of these cables.

  13. Radiofrequency plasma antenna generated by femtosecond laser filaments in air

    SciTech Connect (OSTI)

    Brelet, Y.; Houard, A.; Point, G.; Prade, B.; Carbonnel, J.; Andre, Y.-B.; Mysyrowicz, A. [Laboratoire d'Optique Appliquee, ENSTA ParisTech, Ecole Polytechnique, CNRS, 91761 Palaiseau (France); Arantchouk, L. [Laboratoire de Physique des Plasmas, Ecole Polytechnique, CNRS, Palaiseau (France); Pellet, M. [Etat-major de la Marine Nationale, Paris (France)

    2012-12-24T23:59:59.000Z

    We demonstrate tunable radiofrequency emission from a meter-long linear plasma column produced in air at atmospheric pressure. A short-lived plasma column is initially produced by femtosecond filamentation and subsequently converted into a long-lived discharge column by application of an external high voltage field. Radiofrequency excitation is fed to the plasma by induction and detected remotely as electromagnetic radiation by a classical antenna.

  14. SLIM, Short-pulse Technology for High Gradient Induction Accelerators

    SciTech Connect (OSTI)

    Krasnykh, A.; /SLAC; Kardo-Sysoev, A.; /Ioffe Phys. Tech. Inst.; Arntz, F.; /Diversified Tech., Bedford

    2009-12-09T23:59:59.000Z

    The conclusions of this paper are: (1) The gradient of the SLIM-based technology is believed to be achievable in the same range as it is for the gradient of a modern rf-linac technology ({approx}100 MeV per meter). (2) The SLIM concept is based on the nsec TEM pulse mode operation with no laser or rf systems. (3) Main components of SLIM are not stressed while the energy is pumped into the induction system. Components can accept the hard environment conditions such as a radiation dose, mismatch, hard electromagnetic nose level, etc. Only for several nanoseconds the switch is OFF and produces a stress in the induction system. At that time, the delivery of energy to the beam takes place. (4) The energy in the induction system initially is storied in the magnetic field when the switch is ON. That fact makes another benefit: a low voltage power supplies can be used. The reliability of a lower voltage power supply is higher and they are cheaper. (5) The coreless SLIM concept offers to work in the MHz range of repetition rate. The induction system has the high electric efficiency (much higher than the DWA). (6) The array of lined up and activated SLIM cells is believed to be a solid state structure of novel accelerating technology. The electron-hole plasma in the high power solid state structure is precisely controlled by the electromagnetic process of a pulsed power supply.

  15. Helix coupling

    DOE Patents [OSTI]

    Ginell, W.S.

    1982-03-17T23:59:59.000Z

    A coupling for connecting helix members in series, which consists of a pair of U-shaped elements, one of which is attached to each helix end with the U sections of the elements interlocked. The coupling is particularly beneficial for interconnecting helical Nitinol elements utilized in thermal actuators or engines. Each coupling half is attached to the associated helix at two points, thereby providing axial load while being easily removed from the helix, and reusable.

  16. Helix coupling

    DOE Patents [OSTI]

    Ginell, W.S.

    1989-04-25T23:59:59.000Z

    A coupling for connecting helix members in series, which consists of a pair of U-shaped elements, one of which is attached to each helix end with the "U" sections of the elements interlocked. The coupling is particularly beneficial for interconnecting helical Nitinol elements utilized in thermal actuators or engines. Each coupling half is attached to the associated helix at two points, thereby providing axial load while being easily removed from the helix, and reusable.

  17. Experimental characterization and modeling of non-linear coupling of the LHCD power on Tore Supra

    SciTech Connect (OSTI)

    Preynas, M. [Max Planck Institut für Plasmaphysik, EURATOM Association, D-17491 Greifswald (Germany); Goniche, M.; Hillairet, J.; Litaudon, X.; Ekedahl, A. [CEA, IRFM, F-13108 Saint Paul lez Durance (France)

    2014-02-12T23:59:59.000Z

    To achieve steady state operation on future tokamaks, in particular on ITER, the unique capability of a LHCD system to efficiently drive off-axis non-inductive current is needed. In this context, it is of prime importance to study and master the coupling of LH wave to the core plasma at high power density (tens of MW/m{sup 2}). In some specific conditions, deleterious effects on the LHCD coupling are sometimes observed on Tore Supra. At high power the waves may modify the edge parameters that change the wave coupling properties in a non-linear manner. In this way, dedicated LHCD experiments have been performed using the LHCD system of Tore Supra, composed of two different conceptual designs of launcher: the Fully Active Multijunction (FAM) and the new Passive Active Multijunction (PAM) antennas. A nonlinear interaction between the electron density and the electric field has been characterized in a thin plasma layer in front of the two LHCD antennas. The resulting dependence of the power reflection coefficient with the LHCD power, leading occasionally to trips in the output power, is not predicted by the standard linear theory of the LH wave coupling. Therefore, it is important to investigate and understand the possible origin of such non-linear effects in order to avoid their possible deleterious consequences. The PICCOLO-2D code, which self-consistently treats the wave propagation in the antenna vicinity and its interaction with the local edge plasma density, is used to simulate Tore Supra discharges. The simulation reproduces very well the occurrence of a non-linear behavior in the coupling observed in the LHCD experiments. The important differences and trends between the FAM and the PAM antennas, especially a larger increase in RC for the FAM, are also reproduced by the PICCOLO-2D simulation. The working hypothesis of the contribution of the ponderomotive effect in the non-linear observations of LHCD coupling is therefore validated through this comprehensive modeling for the first time on the FAM and PAM antennas on Tore Supra.

  18. NSTX Weekly Report (November 19, 2010) FY 2011 NSTX plasma operations started on October 4, 2010

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Inductance Plasmas and First RWM State Space Control Experiments in NSTX" by Steve Sabbagh (Columbia. The ovens are presently under argon for assessment of required maintenance. · Molybdenum Inner Divertor

  19. Simulations of BCl{sub 3}/Cl{sub 2}/Ar plasmas with comparisons to diagnostic data

    SciTech Connect (OSTI)

    Meeks, E. [Sandia National Laboratories, Livermore, California 94551-0969 (United States)] [Sandia National Laboratories, Livermore, California 94551-0969 (United States); Ho, P. [Sandia National Laboratories, Albuquerque, New Mexico 87185-5800 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-5800 (United States); Ting, A. [Sandia National Laboratories, Livermore, California 94551-0969 (United States)] [Sandia National Laboratories, Livermore, California 94551-0969 (United States); Buss, R.J. [Sandia National Laboratories, Albuquerque, New Mexico 87185-5800 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185-5800 (United States)

    1998-07-01T23:59:59.000Z

    A reaction mechanism is reported that describes BCl{sub 3}/Cl{sub 2}/Ar plasmas used in the etching of metal lines in microelectronics fabrication processes. Although many of the fundamental electron-impact cross sections for this system are not well known, a reasonable set of reaction paths and rate coefficients has been derived to describe low-pressure reactors with high plasma density. The reaction mechanism describes 59 possible gas-phase events and 18 plasma-surface interactions. A well-mixed reactor model is used to develop the reaction set and to test it against absolute experimental measurements of electron and Cl{sup {minus}} densities, as well as relative measurements of BCl and Cl radicals in an inductively coupled research reactor. The experimental data cover a wide range of operating conditions and gas mixtures. The model provides quantitative agreement with measurements over the whole range of conditions and diagnostics, capturing most of the observed trends. In addition, the model predicts relative ion ratios and Cl/Cl{sub 2} density ratios as measured by molecular beam mass spectrometry. Comparisons of results from the zero-dimensional model and a two-dimensional continuum plasma model, using the same reaction mechanisms, further validate the chemistry set and show the strengths and weaknesses of the well-stirred reactor approach. Sensitivity analysis shows the dominant reactions contributing to model predictions of species densities. {copyright} {ital 1998 American Vacuum Society.}

  20. Application of plasma shield technology to the reduction, treatment, and disposal of hazardous organic and/or mixed wastes with actinide recovery

    SciTech Connect (OSTI)

    Adams, B.T.; Vaughan, L.L.; Joyce, E.L. Jr.; Bieniewski, T.M.

    1990-01-01T23:59:59.000Z

    Los Alamos research activities are currently directed at the application of the shielded hydrogen plasma torch to the direct production of actinide metals from a UF{sub 6} feedstock. Two broad classes of thermal plasma reactors are currently in widespread use: the direct current (dc) arc jet system and the radio frequency (rf) inductively coupled system. Los Alamos has improved upon the basic rf plasma tube design using the concept of a transformer. The unique feature of the Los Alamos tube is a segmented, cooled, internal radiation shield. The Los Alamos shielded plasma torch routinely achieves temperatures exceeding 10,000 K and electron densities of 10{sup 16}/cm{sup 3} when operated continuously at one atmosphere of argon. These highly energetic conditions are sufficient to dissociate most chemical compounds into their constituent atoms. Based upon these characteristics, Los Alamos is currently investigating the application of the shielded plasma torch technology to the destruction of organic and mixed hazardous wastes, as well as the direct production of actinide metals from the halides and oxides, without the cogeneration of contaminated wastes. 5 refs., 4 figs.

  1. Nonabelian plasma instabilities in Bjorken expansion

    E-Print Network [OSTI]

    Anton Rebhan

    2008-10-17T23:59:59.000Z

    Plasma instabilities are parametrically the dominant nonequilibrium dynamics of a weakly coupled quark-gluon plasma. In recent years the time evolution of the corresponding collective colour fields has been studied in stationary anisotropic situations. Here I report on recent numerical results on the time evolution of the most unstable modes in a longitudinally expanding plasma as they grow from small rapidity fluctuations to amplitudes where non-Abelian self-interactions become important.

  2. Comparison of surface vacuum ultraviolet emissions with resonance level number densities. I. Argon plasmas

    SciTech Connect (OSTI)

    Boffard, John B., E-mail: jboffard@wisc.edu; Lin, Chun C. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Culver, Cody [Materials Science Program, University of Wisconsin, Madison, WI 53706 (United States); Wang, Shicong; Wendt, Amy E. [Department of Electrical and Computer Engineering, University of Wisconsin, Madison, WI 53706 (United States); Radovanov, Svetlana; Persing, Harold [Varian Semiconductor Equipment, Applied Materials Inc., Gloucester, MA 01939 (United States)

    2014-03-15T23:59:59.000Z

    Vacuum ultraviolet (VUV) photons emitted from excited atomic states are ubiquitous in material processing plasmas. The highly energetic photons can induce surface damage by driving surface reactions, disordering surface regions, and affecting bonds in the bulk material. In argon plasmas, the VUV emissions are due to the decay of the 1s{sub 4} and 1s{sub 2} principal resonance levels with emission wavelengths of 104.8 and 106.7?nm, respectively. The authors have measured the number densities of atoms in the two resonance levels using both white light optical absorption spectroscopy and radiation-trapping induced changes in the 3p{sup 5}4p?3p{sup 5}4s branching fractions measured via visible/near-infrared optical emission spectroscopy in an argon inductively coupled plasma as a function of both pressure and power. An emission model that takes into account radiation trapping was used to calculate the VUV emission rate. The model results were compared to experimental measurements made with a National Institute of Standards and Technology-calibrated VUV photodiode. The photodiode and model results are in generally good accord and reveal a strong dependence on the neutral gas temperature.

  3. Formation of microchannels from low-temperature plasma-deposited silicon oxynitride

    DOE Patents [OSTI]

    Matzke, Carolyn M. (Los Lunas, NM); Ashby, Carol I. H. (Edgewood, NM); Bridges, Monica M. (Albuquerque, NM); Manginell, Ronald P. (Albuquerque, NM)

    2000-01-01T23:59:59.000Z

    A process for forming one or more fluid microchannels on a substrate is disclosed that is compatible with the formation of integrated circuitry on the substrate. The microchannels can be formed below an upper surface of the substrate, above the upper surface, or both. The microchannels are formed by depositing a covering layer of silicon oxynitride over a mold formed of a sacrificial material such as photoresist which can later be removed. The silicon oxynitride is deposited at a low temperature (.ltoreq.100.degree. C.) and preferably near room temperature using a high-density plasma (e.g. an electron-cyclotron resonance plasma or an inductively-coupled plasma). In some embodiments of the present invention, the microchannels can be completely lined with silicon oxynitride to present a uniform material composition to a fluid therein. The present invention has applications for forming microchannels for use in chromatography and electrophoresis. Additionally, the microchannels can be used for electrokinetic pumping, or for localized or global substrate cooling.

  4. The Automation Of Proof By Mathematical Induction 

    E-Print Network [OSTI]

    Bundy, Alan

    This paper is a chapter of the Handbook of Automated Reasoning edited by Voronkov and Robinson. It describes techniques for automated reasoning in theories containing rules of mathematical induction. Firstly, inductive reasoning is defined and its...

  5. Elevated levels of plasma Big endothelin-1 and its relation to hypertension and skin lesions in individuals exposed to arsenic

    SciTech Connect (OSTI)

    Hossain, Ekhtear; Islam, Khairul; Yeasmin, Fouzia [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh)] [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh); Karim, Md. Rezaul [Department of Applied Nutrition and Food Technology, Islamic University, Kushtia-7003 (Bangladesh)] [Department of Applied Nutrition and Food Technology, Islamic University, Kushtia-7003 (Bangladesh); Rahman, Mashiur; Agarwal, Smita; Hossain, Shakhawoat; Aziz, Abdul; Al Mamun, Abdullah; Sheikh, Afzal; Haque, Abedul; Hossain, M. Tofazzal [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh)] [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh); Hossain, Mostaque [Department of Medicine, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM), Dhaka (Bangladesh)] [Department of Medicine, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM), Dhaka (Bangladesh); Haris, Parvez I. [Faculty of Health and Life Sciences, De Montfort University, Leicester, LE1 9BH (United Kingdom)] [Faculty of Health and Life Sciences, De Montfort University, Leicester, LE1 9BH (United Kingdom); Ikemura, Noriaki; Inoue, Kiyoshi; Miyataka, Hideki; Himeno, Seiichiro [Laboratory of Molecular Nutrition and Toxicology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima 770–8514 (Japan)] [Laboratory of Molecular Nutrition and Toxicology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima 770–8514 (Japan); Hossain, Khaled, E-mail: khossain69@yahoo.com [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh)] [Department of Biochemistry and Molecular Biology, Rajshahi University, Rajshahi-6205 (Bangladesh)

    2012-03-01T23:59:59.000Z

    Chronic arsenic (As) exposure affects the endothelial system causing several diseases. Big endothelin-1 (Big ET-1), the biological precursor of endothelin-1 (ET-1) is a more accurate indicator of the degree of activation of the endothelial system. Effect of As exposure on the plasma Big ET-1 levels and its physiological implications have not yet been documented. We evaluated plasma Big ET-1 levels and their relation to hypertension and skin lesions in As exposed individuals in Bangladesh. A total of 304 study subjects from the As-endemic and non-endemic areas in Bangladesh were recruited for this study. As concentrations in water, hair and nails were measured by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The plasma Big ET-1 levels were measured using a one-step sandwich enzyme immunoassay kit. Significant increase in Big ET-1 levels were observed with the increasing concentrations of As in drinking water, hair and nails. Further, before and after adjusting with different covariates, plasma Big ET-1 levels were found to be significantly associated with the water, hair and nail As concentrations of the study subjects. Big ET-1 levels were also higher in the higher exposure groups compared to the lowest (reference) group. Interestingly, we observed that Big ET-1 levels were significantly higher in the hypertensive and skin lesion groups compared to the normotensive and without skin lesion counterpart, respectively of the study subjects in As-endemic areas. Thus, this study demonstrated a novel dose–response relationship between As exposure and plasma Big ET-1 levels indicating the possible involvement of plasma Big ET-1 levels in As-induced hypertension and skin lesions. -- Highlights: ? Plasma Big ET-1 is an indicator of endothelial damage. ? Plasma Big ET-1 level increases dose-dependently in arsenic exposed individuals. ? Study subjects in arsenic-endemic areas with hypertension have elevated Big ET-1 levels. ? Study subjects with arsenic-induced skin lesions show elevated plasma Big ET-1 levels. ? Arsenic-induced hypertension and skin lesions may be linked to plasma Big ET-1 levels.

  6. Physics Safety Induction OCTOBER 2012

    E-Print Network [OSTI]

    Tobar, Michael

    Physics Safety Induction OCTOBER 2012 FACULTY OF SCIENCES #12;The University of Western Australia · Be safe · Report anything unsafe #12;The University of Western Australia Physics Occupational Safety Sharma ­ ICRAR · Nikita Kostylev ­ Student Representative #12;The University of Western Australia School

  7. THE SCIENCE FRONTIER OF MFE BURNING PLASMA PHYSICS

    E-Print Network [OSTI]

    plasma and self-heating issues for magnetic fusion. #12;THERE ARE TWO TYPES OF BURNING PLASMA ISSUES PHENOMENA #12;MANY NEW AND EXCITING PHENOMENA TO STUDY IN A BP NEW ELEMENTS IN A BURNING PLASMAS: SELF-HEATED-ALFVéNIC ALPHAS · HIGHLY NON-LINEAR INTERACTION OF ALPHA SELF-HEATING WITH STRONGLY COUPLED ADVANCED TOKAMAK

  8. INDUCTION MOTOR FAULT DIAGNOSTIC AND MONITORING METHODS

    E-Print Network [OSTI]

    Povinelli, Richard J.

    INDUCTION MOTOR FAULT DIAGNOSTIC AND MONITORING METHODS by Aderiano M. da Silva, B.S. A Thesis;i Abstract Induction motors are used worldwide as the "workhorse" in industrial applications material. However, induction motor faults can be detected in an initial stage in order to prevent

  9. Plasma accelerator

    DOE Patents [OSTI]

    Wang, Zhehui (Los Alamos, NM); Barnes, Cris W. (Santa Fe, NM)

    2002-01-01T23:59:59.000Z

    There has been invented an apparatus for acceleration of a plasma having coaxially positioned, constant diameter, cylindrical electrodes which are modified to converge (for a positive polarity inner electrode and a negatively charged outer electrode) at the plasma output end of the annulus between the electrodes to achieve improved particle flux per unit of power.

  10. Meter scale plasma source for plasma wakefield experiments

    SciTech Connect (OSTI)

    Vafaei-Najafabadi, N.; Shaw, J. L.; Marsh, K. A.; Joshi, C.; Hogan, M. J. [Department of Electrical Engineering, University of California Los Angeles, Los Angeles, CA 90095 (United States); SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States)

    2012-12-21T23:59:59.000Z

    High accelerating gradients generated by a high density electron beam moving through plasma has been used to double the energy of the SLAC electron beam [1]. During that experiment, the electron current density was high enough to generate its own plasma without significant head erosion. In the newly commissioned FACET facility at SLAC, the peak current will be lower and without pre-ionization, head erosion will be a significant challenge for the planned experiments. In this work we report on our design of a meter scale plasma source for these experiments to effectively avoid the problem of head erosion. The plasma source is based on a homogeneous metal vapor gas column that is generated in a heat pipe oven [2]. A lithium oven over 30 cm long at densities over 10{sup 17} cm{sup -3} has been constructed and tested at UCLA. The plasma is then generated by coupling a 10 TW short pulse Ti:Sapphire laser into the gas column using an axicon lens setup. The Bessel profile of the axicon setup creates a region of high intensity that can stretch over the full length of the gas column with approximately constant diameter. In this region of high intensity, the alkali metal vapor is ionized through multi-photon ionization process. In this manner, a fully ionized meter scale plasma of uniform density can be formed. Methods for controlling the plasma diameter and length will also be discussed.

  11. Segmented rail linear induction motor

    SciTech Connect (OSTI)

    Cowan, M. Jr.; Marder, B.M.

    1996-09-03T23:59:59.000Z

    A segmented rail linear induction motor has a segmented rail consisting of a plurality of nonferrous electrically conductive segments aligned along a guideway. The motor further includes a carriage including at least one pair of opposed coils fastened to the carriage for moving the carriage. A power source applies an electric current to the coils to induce currents in the conductive surfaces to repel the coils from adjacent edges of the conductive surfaces. 6 figs.

  12. Runaway electrons in a fully and partially ionized nonideal plasma

    SciTech Connect (OSTI)

    Ramazanov, T.S.; Turekhanova, K.M. [Al Farabi Kazakh National University, IETP, Tole bi 96a, Almaty 050012 (Kazakhstan)

    2005-10-01T23:59:59.000Z

    This paper reports on a study of electron runaway for a nonideal plasma in an external electric field. Based on pseudopotential models of nonideal fully and partially ionized plasmas, the friction force was derived as a function of electron velocities. Dependences of the electron free path on plasma density and nonideality parameters were obtained. The impact of the relative number of runaway electrons on their velocity and temperature was considered for classical and semiclassical models of a nonideal plasma. It has been shown that for the defined intervals of the coupled plasma parameter, the difference between the relative numbers of runaway electron values is essential for various plasma models.

  13. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Author: G. Taylor Date ATI ­ ET Group Leader: G. Taylor Date RLM - Run Coordinator: E. Fredrickson Date-Driven 100% Non-Inductive H-Mode Plasma No. OP-XP-1010 AUTHORS: G. Taylor, D. Mueller, J.C. Hosea, S. Gerhardt, C. Kessel, B.P. LeBlanc, C.K. Phillips, S. Zweben, R. Maingi, P.M. Ryan, R. Maingi DATE: February

  14. High frequency inductive lamp and power oscillator

    DOE Patents [OSTI]

    MacLennan, Donald A. (Gaithersburg, MD); Dymond, Jr., Lauren E. (North Potomac, MD); Gitsevich, Aleksandr (Montgomery Village, MD); Grimm, William G. (Silver Spring, MD); Kipling, Kent (Gaithersburg, MD); Kirkpatrick, Douglas A. (Great Falls, VA); Ola, Samuel A. (Silver Spring, MD); Simpson, James E. (Gaithersburg, MD); Trimble, William C. (Columbia, MD); Tsai, Peter (Olney, MD); Turner, Brian P. (Damascus, MD)

    2001-01-01T23:59:59.000Z

    A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and I or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to adjust the driving frequency of the oscillator.

  15. High frequency inductive lamp and power oscillator

    DOE Patents [OSTI]

    MacLennan, Donald A. (Gaithersburg, MD); Turner, Brian P. (Damascus, MD); Dolan, James T. (Frederick, MD); Kirkpatrick, Douglas A. (Great Falls, VA); Leng, Yongzhang (Damascus, MD)

    2000-01-01T23:59:59.000Z

    A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and/or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to match the driving frequency of the oscillator to a plurality of tuning states of the lamp.

  16. Comparative Analysis of Carbon Plasma in Arc and RF Reactors

    SciTech Connect (OSTI)

    Todorovic-Markovic, B.; Markovic, Z. ['Vinca' Institute of Nuclear Sciences, P.O.B. 522, 11001 Belgrade (Serbia and Montenegro); Mohai, I.; Szepvolgyi, J. [Research Laboratory of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences H-1525 Budapest, POB 17 (Hungary)

    2004-12-01T23:59:59.000Z

    Results on studies of molecular spectra emitted in the initial stages of fullerene formation during the processing of graphite powder in induction RF reactor and evaporation of graphite electrodes in arc reactor are presented in this paper. It was found that C2 radicals were dominant molecular species in both plasmas. C2 radicals have an important role in the process of fullerene synthesis. The rotational-vibrational temperatures of C2 and CN species were calculated by fitting the experimental spectra to the simulated ones. The results of optical emission study of C2 radicals generated in carbon arc plasma have shown that rotational temperature of C2 species depends on carbon concentration and current intensity significantly. The optical emission study of induction RF plasma and SEM analysis of graphite powder before and after plasma treatment have shown that evaporation of the processed graphite powder depends on feed rate and composition of gas phase significantly. Based on the obtained results, it was concluded that in the plasma region CN radicals could be formed by the reaction of C2 species with atomic nitrogen at smaller loads. At larger feed rate of graphite powder, CN species were produced by surface reaction of the hot carbon particles with nitrogen atoms. The presence of nitrogen in induction RF plasma reduces the fullerene yield significantly. The fullerene yield obtained in two different reactors was: 13% in arc reactor and 4.1% in induction RF reactor. However, the fullerene production rate was higher in induction RF reactor-6.4 g/h versus 1.7 g/h in arc reactor.

  17. Plasma gun notes Here are some notes based on an idea of Paul Bellan's (see his Spheromak

    E-Print Network [OSTI]

    Brown, Michael R.

    Plasma gun notes Here are some notes based on an idea of Paul Bellan's (see his Spheromak book end C. L is an inductance per unit length and L0 is the inductance of the system before the spheromak starts to move. The spheromak is a sliding short of mass m impaled on the center electrode. The potential

  18. A segmented multi-loop antenna for selective excitation of azimuthal mode number in a helicon plasma source

    SciTech Connect (OSTI)

    Shinohara, S., E-mail: sshinoha@cc.tuat.ac.jp [Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan); Tanikawa, T. [Research Institute of Science and Technology, Tokai University, 4-1-1, Kita-kaname, Hiratsuka, Kanagawa 259-1292 (Japan); Motomura, T. [National Institute of Advanced Industrial Science and Technology (AIST), 807-1, Shuku-machi, Tosu, Saga 841-0052 Japan (Japan)

    2014-09-15T23:59:59.000Z

    A flat type, segmented multi-loop antenna was developed in the Tokai Helicon Device, built for producing high-density helicon plasma, with a diameter of 20 cm and an axial length of 100 cm. This antenna, composed of azimuthally splitting segments located on four different radial positions, i.e., r = 2.8, 4.8, 6.8, and 8.8 cm, can excite the azimuthal mode number m of 0, ±1, and ±2 by a proper choice of antenna feeder parts just on the rear side of the antenna. Power dependencies of the electron density n{sub e} were investigated with a radio frequency (rf) power less than 3 kW (excitation frequency ranged from 8 to 20 MHz) by the use of various types of antenna segments, and n{sub e} up to ?5 × 10{sup 12} cm{sup ?3} was obtained after the density jump from inductively coupled plasma to helicon discharges. Radial density profiles of m = 0 and ±1 modes with low and high rf powers were measured. For the cases of these modes after the density jump, the excited mode structures derived from the magnetic probe measurements were consistent with those expected from theory on helicon waves excited in the plasma.

  19. Method and apparatus for the formation of a spheromak plasma

    DOE Patents [OSTI]

    Yamada, Masaaki (Lawrenceville, NJ); Furth, Harold P. (Princeton, NJ); Stix, Thomas H. (Princeton, NJ); Todd, Alan M. M. (Princeton Junction, NJ)

    1982-01-01T23:59:59.000Z

    A method and apparatus for forming a detached, compact toroidally shaped spheromak plasma by an inductive mechanism. A generally spheroidal vacuum vessel (1) houses a toroidally shaped flux ring or core (2) which contains poloidal and toroidal field generating coils. A plasma discharge occurs with the pulsing of the toroidal field coil, and the plasma is caused to expand away from the core (2) and toward the center of the vacuum vessel (1). When the plasma is in an expanded state, a portion of it is pinched off in order to form a separate, detached spheromak plasma configuration. The detached plasma is supported by a magnetic field generated by externally arranged equilibrium field coils (5).

  20. Ultrastrong coupling in two-resonator circuit QED

    E-Print Network [OSTI]

    A. Baust; E. Hoffmann; M. Haeberlein; M. J. Schwarz; P. Eder; J. Goetz; F. Wulschner; E. Xie; L. Zhong; F. Quijandria; D. Zueco; J. -J. Garcia Ripoll; L. Garcia-Alvarez; G. Romero; E. Solano; K. G. Fedorov; E. P. Menzel; F. Deppe; A. Marx; R. Gross

    2014-12-23T23:59:59.000Z

    We report on ultrastrong coupling between a superconducting flux qubit and a resonant mode of a system comprised of two superconducting coplanar stripline resonators coupled galvanically to the qubit. With a coupling strength as high as 17% of the mode frequency, exceeding that of previous circuit quantum electrodynamics experiments, we observe a pronounced Bloch-Siegert shift. The spectroscopic response of our multimode system reveals a clear breakdown of the Jaynes-Cummings model. In contrast to earlier experiments, the high coupling strength is achieved without making use of an additional inductance provided by a Josephson junction.

  1. Chemical Evolution of Metal in Refractory Inclusions in CV3 ANDREW J. CAMPBELL*,1

    E-Print Network [OSTI]

    Campbell, Andrew

    . Clayton #12;2 Abstract­Laser ablation inductively coupled plasma mass spectrometry (LA-ICP- MS) was used

  2. Claude Dalpe Don R. Baker Experimental investigation of large-ion-lithophile-element-,

    E-Print Network [OSTI]

    Long, Bernard

    -earth elements (REE: La to Lu; +Y) were measured with a LASER ablation inductively coupled plasma ± mass

  3. Origin of kamacite, schreibersite, and perryite in metal-sulfide nodules of the enstatite chondrite Sahara 97072 (EH3)

    E-Print Network [OSTI]

    Mcdonough, William F.

    with laser ablation, inductively coupled plasma mass spectrometry (ICP- MS). We also measured their Fe, Ni, P

  4. Monitoring transients in low inductance circuits

    DOE Patents [OSTI]

    Guilford, R.P.; Rosborough, J.R.

    1985-10-21T23:59:59.000Z

    The instant invention relates to methods of and apparatus for monitoring transients in low inductance circuits and to a probe utilized to practice said method and apparatus. More particularly, the instant invention relates to methods of and apparatus for monitoring low inductance circuits, wherein the low inductance circuits include a pair of flat cable transmission lines. The instant invention is further directed to a probe for use in monitoring pairs of flat cable transmission lines.

  5. Ramp-up of CHI Initiated Plasmas on NSTX

    SciTech Connect (OSTI)

    Mueller, D; Bell, R E; LeBlanc, B; Roquemore, A L; Raman, R; Jarboe, T R; Nelson, B A

    2009-10-29T23:59:59.000Z

    Experiments on the National Spherical Torus (NSTX) have now demonstrated flux savings using transient coaxial helicity injection (CHI). In these discharges, the discharges initiated by CHI are ramped up with an inductive transformer and exhibit higher plasma current than discharges without the benefit of CHI initiation.

  6. Low inductance power electronics assembly

    DOE Patents [OSTI]

    Herron, Nicholas Hayden; Mann, Brooks S.; Korich, Mark D.; Chou, Cindy; Tang, David; Carlson, Douglas S.; Barry, Alan L.

    2012-10-02T23:59:59.000Z

    A power electronics assembly is provided. A first support member includes a first plurality of conductors. A first plurality of power switching devices are coupled to the first support member. A first capacitor is coupled to the first support member. A second support member includes a second plurality of conductors. A second plurality of power switching devices are coupled to the second support member. A second capacitor is coupled to the second support member. The first and second pluralities of conductors, the first and second pluralities of power switching devices, and the first and second capacitors are electrically connected such that the first plurality of power switching devices is connected in parallel with the first capacitor and the second capacitor and the second plurality of power switching devices is connected in parallel with the second capacitor and the first capacitor.

  7. Cold atmospheric plasma in cancer therapy

    SciTech Connect (OSTI)

    Keidar, Michael; Shashurin, Alex; Volotskova, Olga [Mechanical and Aerospace Engineering, George Washington University, Washington DC 20052 (United States)] [Mechanical and Aerospace Engineering, George Washington University, Washington DC 20052 (United States); Ann Stepp, Mary [Medical School, George Washington University, Washington DC 20052 (United States)] [Medical School, George Washington University, Washington DC 20052 (United States); Srinivasan, Priya; Sandler, Anthony [Childrens National Medical Center, Washington DC 20010 (United States)] [Childrens National Medical Center, Washington DC 20010 (United States); Trink, Barry [Head and Neck Cancer Research Division, Department of Otolaryngology, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21205 (United States)] [Head and Neck Cancer Research Division, Department of Otolaryngology, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21205 (United States)

    2013-05-15T23:59:59.000Z

    Recent progress in atmospheric plasmas has led to the creation of cold plasmas with ion temperature close to room temperature. This paper outlines recent progress in understanding of cold plasma physics as well as application of cold atmospheric plasma (CAP) in cancer therapy. Varieties of novel plasma diagnostic techniques were developed recently in a quest to understand physics of CAP. It was established that the streamer head charge is about 10{sup 8} electrons, the electrical field in the head vicinity is about 10{sup 7} V/m, and the electron density of the streamer column is about 10{sup 19} m{sup ?3}. Both in-vitro and in-vivo studies of CAP action on cancer were performed. It was shown that the cold plasma application selectively eradicates cancer cells in-vitro without damaging normal cells and significantly reduces tumor size in-vivo. Studies indicate that the mechanism of action of cold plasma on cancer cells is related to generation of reactive oxygen species with possible induction of the apoptosis pathway. It is also shown that the cancer cells are more susceptible to the effects of CAP because a greater percentage of cells are in the S phase of the cell cycle.

  8. Induction slag reduction process for making titanium

    DOE Patents [OSTI]

    Traut, Davis E. (Corvallis, OR)

    1991-01-01T23:59:59.000Z

    Continuous process for preparing titanium comprising fluorinating titanium ore, and reducing the formed alkaline earth fluotitanate with an alkaline earth metal in an induction slag reactor.

  9. Six-phase induction machine operating as a stand-alone self-excited induction generator

    E-Print Network [OSTI]

    Brest, Université de

    -excited induction generator and supplying various loads under different conditions are presented. Firstly generators are particularly used in small and isolated power plants based on wind turbine or hydroelectricSix-phase induction machine operating as a stand- alone self-excited induction generator Kamel

  10. Electrochemical characteristics of plasma-etched black silicon as anodes for Li-ion batteries

    SciTech Connect (OSTI)

    Lee, Gibaek; Wehrspohn, Ralf B., E-mail: ralf.b.wehrspohn@iwmh.fraunhofer.de [Fraunhofer Institute for Mechanics of Materials IWM, Halle (Saale) 06120, Germany and Department of Physics, Martin-Luther University, Halle (Saale) 06099 (Germany); Schweizer, Stefan L. [Department of Physics, Martin-Luther University, Halle (Saale) 06099 (Germany)

    2014-11-01T23:59:59.000Z

    Nanostructured silicon as an anode material for Li-ion batteries is produced for the first time by inductively coupled plasma–plasma etching of Si wafers in the black silicon regime. The microscopic structure strongly resembles other types of nanostructured silicon, with a well-arranged nanostructure possessing a sufficient porosity for accommodating large volume expansion. Despite these features, however, a high first-cycle irreversible capacity loss and a poor cycle life are observed. The main reason for these poor features is the formation of a thick solid-electrolyte interphase (SEI) layer related to the surface condition of the pristine nanostructured black silicon (b-Si) electrode. Therefore, the cycle life of the b-Si electrode is heavily influenced by the constant reformation of the SEI layer depending upon the surface composition in spite of the presence of nanostructured Si. In the fast lithiation experiments, the nanostructure region of the b-Si electrode is detached from the Si substrate owing to the kinetics difference between the lithium ion diffusion and the electron injection and phase transformation in the nanostructured Si region. This means that more Si substrate is involved in lithiation at high current rates. It is therefore important to maintain balance in the chemical kinetics during the lithiation of nanostructured Si electrodes with a Si substrate.

  11. Internal distribution of Li and B in serpentinites from the Feather River Ophiolite, California, based on laser ablation

    E-Print Network [OSTI]

    Lee, Cin-Ty Aeolus

    , based on laser ablation inductively coupled plasma mass spectrometry Cin-Ty Aeolus Lee, Masaru Oka Occidentale, UMR6538, CNRS, F-29238 Brest CEDEX 3, France [1] Laser ablation inductively coupled plasma mass Ophiolite, California, based on laser ablation inductively coupled plasma mass spectrometry, Geochem

  12. Couple lectromcanique des machines rluctance Vernier excites commutation lectronique

    E-Print Network [OSTI]

    Boyer, Edmond

    reluctance machines including a stator field winding. A Fourier series analysis of electric and magnetic'un point de l'entrefer par rapport au stator (rad . ou 0). B induction magnétique (T). C couple angulaire rotor/stator (rad.). u03B8(03B1) différence de potentiel magnétique scalaire stator/ rotor (A). u0

  13. university-logo Induction Week: Welcome

    E-Print Network [OSTI]

    Koehn, Philipp

    university-logo Induction Week: Welcome Alex Lascarides TH E U N I V E R S ITY OF E D I N B U R G H September, 2012 Alex Lascarides PhD Induction Week #12;university-logo Welcome People Alex Lascarides;university-logo What the IGS does for PhD students Admissions and funding Supervisory arrangements Monitoring

  14. Hydrodynamics of the cascading plasma

    E-Print Network [OSTI]

    Alex Buchel

    2009-06-03T23:59:59.000Z

    The cascading gauge theory of Klebanov et.al realizes a soluble example of gauge/string correspondence in a non-conformal setting. Such a gauge theory has a strong coupling scale Lambda, below which it confines with a chiral symmetry breaking. A holographic description of a strongly coupled cascading gauge theory plasma is represented by a black brane solution of type IIB supergravity on a conifold with fluxes. A characteristic parameter controlling the high temperature expansion of such plasma is 1/ln(T/Lambda). In this paper we study the speed of sound and the bulk viscosity of the cascading gauge theory plasma to order 1/ln(T/Lambda)^4. We find that the bulk viscosity satisfies the bound conjectured in arXiv:0708.3459. We comment on difficulties of computing the transport coefficients to all orders in T/Lambda. Previously, it was shown that a cascading gauge theory plasma undergoes a first-order deconfinement transition with unbroken chiral symmetry at T_c=0.6141111(3) Lambda. We show here that a deconfined chirally symmetric phase becomes perturbatively unstable at T_u=0.8749(0) T_c. Near the unstable point the specific heat diverges as c_V ~ |1-T_u/T|^(-1/2).

  15. Thermoacoustic couple

    DOE Patents [OSTI]

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1983-10-04T23:59:59.000Z

    An apparatus and method for determining acoustic power density level and its direction in a fluid using a single sensor are disclosed. The preferred embodiment of the apparatus, which is termed a thermoacoustic couple, consists of a stack of thin, spaced apart polymeric plates, selected ones of which include multiple bimetallic thermocouple junctions positioned along opposite end edges thereof. The thermocouple junctions are connected in series in the nature of a thermopile, and are arranged so as to be responsive to small temperature differences between the opposite edges of the plates. The magnitude of the temperature difference, as represented by the magnitude of the electrical potential difference generated by the thermopile, is found to be directly related to the level of acoustic power density in the gas.

  16. Matching network for RF plasma source

    DOE Patents [OSTI]

    Pickard, Daniel S. (Palo Alto, CA); Leung, Ka-Ngo (Hercules, CA)

    2007-11-20T23:59:59.000Z

    A compact matching network couples an RF power supply to an RF antenna in a plasma generator. The simple and compact impedance matching network matches the plasma load to the impedance of a coaxial transmission line and the output impedance of an RF amplifier at radio frequencies. The matching network is formed of a resonantly tuned circuit formed of a variable capacitor and an inductor in a series resonance configuration, and a ferrite core transformer coupled to the resonantly tuned circuit. This matching network is compact enough to fit in existing compact focused ion beam systems.

  17. Element of an inductive coupler

    DOE Patents [OSTI]

    Hall, David R.; Fox, Joe

    2006-08-15T23:59:59.000Z

    An element for an inductive coupler in a downhole component comprises magnetically conductive material, which is disposed in a recess in annular housing. The magnetically conductive material forms a generally circular trough. The circular trough comprises an outer generally U-shaped surface, an inner generally U-shaped surface, and two generally planar surfaces joining the inner and outer surfaces. The element further comprises pressure relief grooves in at least one of the surfaces of the circular trough. The pressure relief grooves may be scored lines. Preferably the pressure relief grooves are parallel to the magnetic field generated by the magnetically conductive material. The magnetically conductive material is selected from the group consisting of soft iron, ferrite, a nickel iron alloy, a silicon iron alloy, a cobalt iron alloy, and a mu-metal. Preferably, the annular housing is a metal ring.

  18. Effective Interaction Potentials and Physical Properties of Complex Plasmas

    SciTech Connect (OSTI)

    Ramazanov, T. S.; Dzhumagulova, K. N.; Gabdullin, M. T.; Omarbakiyeva, Y. A. [Institute of Experimental and Theoretical Physics, al-Farabi Kazakh National University, 96a Tole Bi, Almaty 050012 (Kazakhstan)

    2009-11-10T23:59:59.000Z

    Microscopic, thermodynamic and transport properties of complex plasmas are investigated on the basis of effective potentials of interparticle interaction. These potentials take into account correlation effects and quantum-mechanical diffraction. Plasma composition, thermodynamic functions of hydrogen and helium plasmas are obtained for a wide region of coupling parameter. Collision processes in partially ionized plasma are considered; some kinetic characteristics such as phase shift, scattering cross section, bremsstrahlung cross section and absorption coefficient are investigated. Dynamic and transport properties of dusty plasma are studied by computer simulation method of the Langevin dynamics.

  19. Method and apparatus for steady-state magnetic measurement of poloidal magnetic field near a tokamak plasma

    DOE Patents [OSTI]

    Woolley, Robert D. (Hillsborough, NJ)

    1998-01-01T23:59:59.000Z

    A method and apparatus for the steady-state measurement of poloidal magnetic field near a tokamak plasma, where the tokamak is configured with respect to a cylindrical coordinate system having z, phi (toroidal), and r axes. The method is based on combining the two magnetic field principles of induction and torque. The apparatus includes a rotor assembly having a pair of inductive magnetic field pickup coils which are concentrically mounted, orthogonally oriented in the r and z directions, and coupled to remotely located electronics which include electronic integrators for determining magnetic field changes. The rotor assembly includes an axle oriented in the toroidal direction, with the axle mounted on pivot support brackets which in turn are mounted on a baseplate. First and second springs are located between the baseplate and the rotor assembly restricting rotation of the rotor assembly about its axle, the second spring providing a constant tensile preload in the first spring. A strain gauge is mounted on the first spring, and electronic means to continually monitor strain gauge resistance variations is provided. Electronic means for providing a known current pulse waveform to be periodically injected into each coil to create a time-varying torque on the rotor assembly in the toroidal direction causes mechanical strain variations proportional to the torque in the mounting means and springs so that strain gauge measurement of the variation provides periodic magnetic field measurements independent of the magnetic field measured by the electronic integrators.

  20. Method and apparatus for steady-state magnetic measurement of poloidal magnetic field near a tokamak plasma

    DOE Patents [OSTI]

    Woolley, R.D.

    1998-09-08T23:59:59.000Z

    A method and apparatus are disclosed for the steady-state measurement of poloidal magnetic field near a tokamak plasma, where the tokamak is configured with respect to a cylindrical coordinate system having z, phi (toroidal), and r axes. The method is based on combining the two magnetic field principles of induction and torque. The apparatus includes a rotor assembly having a pair of inductive magnetic field pickup coils which are concentrically mounted, orthogonally oriented in the r and z directions, and coupled to remotely located electronics which include electronic integrators for determining magnetic field changes. The rotor assembly includes an axle oriented in the toroidal direction, with the axle mounted on pivot support brackets which in turn are mounted on a baseplate. First and second springs are located between the baseplate and the rotor assembly restricting rotation of the rotor assembly about its axle, the second spring providing a constant tensile preload in the first spring. A strain gauge is mounted on the first spring, and electronic means to continually monitor strain gauge resistance variations is provided. Electronic means for providing a known current pulse waveform to be periodically injected into each coil to create a time-varying torque on the rotor assembly in the toroidal direction causes mechanical strain variations proportional to the torque in the mounting means and springs so that strain gauge measurement of the variation provides periodic magnetic field measurements independent of the magnetic field measured by the electronic integrators. 6 figs.

  1. DOE - Office of Legacy Management -- Tocco Induction Heating...

    Office of Legacy Management (LM)

    Tocco Induction Heating Div of Ohio Crankshaft Co - OH 42 FUSRAP Considered Sites Site: TOCCO INDUCTION HEATING, DIV. OF OHIO CRANKSHAFT CO. (OH.42 ) Eliminated from consideration...

  2. axial view inductively: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    View of Induction Reasoning for First-Order Logic Physics Websites Summary: , The Alan Turing Centenary Conference (2012)" 12;A Unified View of Induction Reasoning for First in...

  3. Multi-scale investigation of sheared flows in magnetized plasmas

    SciTech Connect (OSTI)

    Thomas, Jr., Dr. Edward

    2014-09-19T23:59:59.000Z

    Flows parallel and perpendicular to magnetic fields in a plasma are important phenomena in many areas of plasma science research. The presence of these spatially inhomogeneous flows is often associated with the stability of the plasma. In fusion plasmas, these sheared flows can be stabilizing while in space plasmas, these sheared flows can be destabilizing. Because of this, there is broad interest in understanding the coupling between plasma stability and plasma flows. This research project has engaged in a study of the plasma response to spatially inhomogeneous plasma flows using three different experimental devices: the Auburn Linear Experiment for Instability Studies (ALEXIS) and the Compact Toroidal Hybrid (CTH) stellarator devices at Auburn University, and the Space Plasma Simulation Chamber (SPSC) at the Naval Research Laboratory. This work has shown that there is a commonality of the plasma response to sheared flows across a wide range of plasma parameters and magnetic field geometries. The goal of this multi-device, multi-scale project is to understand how sheared flows established by the same underlying physical mechanisms lead to different plasma responses in fusion, laboratory, and space plasmas.

  4. Effect of Inert Gas Additive Species on Cl(2) High Density Plasma Etching of Compound Semiconductors: Part 1. GaAs and GaSb

    SciTech Connect (OSTI)

    Abernathy, C.R.; Cho, H.; Hahn, Y.B.; Hays, D.C.; Jung, K.B.; Pearton, S.J.; Shul, R.J.

    1998-12-23T23:59:59.000Z

    The role of the inert gas additive (He, Ar, Xe) to C12 Inductively Coupled Plasmas for dry etching of GaAs and GaSb was examined through the effect on etch rate, surface roughness and near-surface stoichiometry. The etch rates for both materials go through a maximum with Clz 0/0 in each type of discharge (C12/'He, C12/Ar, C12/Xc), reflecting the need to have efficient ion-assisted resorption of the etch products. Etch yields initially increase strongly with source power as the chlorine neutral density increases, but decrease again at high powers as the etching becomes reactant-limited. The etched surfaces are generally smoother with Ax or Xe addition, and maintain their stoichiometry.

  5. Black holes and the quark-gluon plasma

    E-Print Network [OSTI]

    George Siopsis

    2009-01-26T23:59:59.000Z

    I discuss the possibility that the quark-gluon plasma at strong coupling admits a description in terms of a black hole in asymptotically anti-de Sitter space.

  6. Quantum corrections to screening at strong coupling

    E-Print Network [OSTI]

    Ajay Singh; Aninda Sinha

    2012-04-23T23:59:59.000Z

    We compute a certain class of corrections to (specific) screening lengths in strongly coupled nonabelian plasmas using the AdS/CFT correspondence. In this holographic framework, these corrections arise from various higher curvature interactions modifying the leading Einstein gravity action. The changes in the screening lengths are perturbative in inverse powers of the 't Hooft coupling or of the number of colours, as can be made precise in the context where the dual gauge theory is superconformal. We also compare the results of these holographic calculations to lattice results for the analogous screening lengths in QCD. In particular, we apply these results within the program of making quantitative comparisons between the strongly coupled quark-gluon plasma and holographic descriptions of conformal field theory.

  7. Ionization Equilibrium Timescales in Collisional Plasmas

    E-Print Network [OSTI]

    Smith, Randall K

    2010-01-01T23:59:59.000Z

    Astrophysical shocks or bursts from a photoionizing source can disturb the typical collisional plasma found in galactic interstellar media or the intergalactic medium. The spectrum emitted by this plasma contains diagnostics that have been used to determine the time since the disturbing event, although this determination becomes uncertain as the elements in the plasma return to ionization equilibrium. A general solution for the equilibrium timescale for each element arises from the elegant eigenvector method of solution to the problem of a non-equilibrium plasma described by Masai (1984) and Hughes & Helfand (1985). In general the ionization evolution of an element Z in a constant electron temperature plasma is given by a coupled set of Z+1 first order differential equations. However, they can be recast as Z uncoupled first order differential equations using an eigenvector basis for the system. The solution is then Z separate exponential functions, with the time constants given by the eigenvalues of the r...

  8. U.S. Department of Energy Categorical Exclusion ...

    Broader source: Energy.gov (indexed) [DOE]

    AikenSouth Carolina The Analytical Development VG PlasmaQuad II Inductively Coupled Plasma Mass Spectrometers (ICPMS) perform elemental and isotopic analysis on liquid samples....

  9. Kron`s reduction method applied to the time stepping finite element analysis of induction machines

    SciTech Connect (OSTI)

    Degeneff, R.C.; Gutierrez, M.R.; Salon, S.J.; Burow, D.W. [Rensselaer Polytechnic Inst., Troy, NY (United States). Electric Power Engineering Dept.] [Rensselaer Polytechnic Inst., Troy, NY (United States). Electric Power Engineering Dept.; Nevins, R.J. [Martin Marietta Corp., Schenectady, NY (United States)] [Martin Marietta Corp., Schenectady, NY (United States)

    1995-12-01T23:59:59.000Z

    The behavior of large induction motors during transient as well as steady state running conditions is of significant interest to the power industry. A variety of analytical predictive tools are employed to aid the design and predict their operation under transient and steady state conditions. One of the most powerful method for investigating the transient behavior of induction machines is a coupled time stepping finite element analysis which can combine electromagnetic fields, circuits and mechanical systems. Due to the complexity of the finite element induction machine model and the resulting large number of describing equations, the computation time required for such programs to solve practical problems becomes a major limitation. This becomes even more of a concern when different design options or operating scenarios are evaluated. This paper presents a strategy to reduce the required running time in order to make a parametric study of induction machines such as the assessment of different design options feasible. This is accomplished by reducing the number of finite element equations that must be solved while maintaining the same level of accuracy of solutions. This method is based on Kron`s network reduction work for linear systems and has successfully been applied to large lumped parameter model of transformers. This paper illustrates the reduction method by comparing the flux density in the air gap for a complete FEM model of an induction machine to that of the reduced model. The results are essentially identical with a reduction in computational time of approximately 71%.

  10. PHYSICAL REVIEW E 83, 046405 (2011) Dynamic model of streamer coupling for the homogeneity of glowlike dielectric barrier discharges

    E-Print Network [OSTI]

    Economou, Demetre J.

    2011-01-01T23:59:59.000Z

    PHYSICAL REVIEW E 83, 046405 (2011) Dynamic model of streamer coupling for the homogeneity. Economou Department of Chemical and Biomolecular Engineering, Plasma Processing Laboratory, University 2011; published 18 April 2011) A streamer coupling theory is developed to describe the formation

  11. Instabilities in Zakharov Equations for Laser Propagation in a Plasma

    E-Print Network [OSTI]

    Métivier, Guy

    and the electronic plasma waves (see [CC1, CC2] for example). The laser beam and the Raman component correspond in a laboratory nuclear fusion by inertial confinement. This requires precise and reliable models for laser electronic plasma waves. These systems couple the slowly varying envelope of the electric field and the low

  12. Plasma-sheath effects on the Debye screening problem

    SciTech Connect (OSTI)

    Sarmah, D.; Tessarotto, M.; Salimullah, M. [Department of Mathematics and Informatics, University of Trieste, Trieste (Italy); International Center for Theoretical Physics, ICPT/TRIL, Program, Trieste (Italy); and Consortium for Magnetofluid Dynamics, Trieste (Italy); Department of Mathematics and Informatics, University of Trieste, Trieste (Italy) and Consortium for Magnetofluid Dynamics, Trieste (Italy); Department of Physics, Jahangirnagar University, Savar, Dhaka (Bangladesh)

    2006-03-15T23:59:59.000Z

    The classical Debye-Hueckel screening effect of the electrostatic field generated by isolated charged particles immersed in a plasma is reviewed. The validity of the underlying mathematical model, and particularly of the weak-field approximation, is analyzed. It is shown that the presence of the plasma sheath around test particles and the resulting effect of charge screening are essential for the description of plasmas that are strongly coupled.

  13. New plasma chemistries for dry etching of InGaAlP alloys: BI{sub 3} and BBr{sub 3}

    SciTech Connect (OSTI)

    Hong, J.; Cho, H.; Maeda, T.; Abernathy, C.R.; Pearton, S.J. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Shul, R.J. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Hobson, W.S. [Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey 07974 (United States)] [Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey 07974 (United States)

    1998-09-01T23:59:59.000Z

    Inductively coupled plasma etching of InGaP, AlInP and AlGaP in BI{sub 3} or BBr{sub 3} discharges was investigated as a function of source power, dc chuck bias and plasma composition. InGaP etches at the fastest rates ({gt}6000thinsp{Angstrom}thinspmin{sup {minus}1}) in both chemistries, followed by AlGaP. It is found that AlInP provides an excellent etch stop for the other two materials in both mixtures. The InGaP surface morphology improves with increasing BI{sub 3} or BBr{sub 3} content, and with increasing dc chuck bias. The etched features for this material are highly anisotropic. Etch selectivities for InGaP over SiO{sub 2} and SiN{sub x} of {ge}8 are obtained in both plasma chemistries, and there is no etch incubation time with either mixture, indicating that both can scavenge the native oxide on InGaP, AlGaP and AlInP. {copyright} {ital 1998 American Vacuum Society.}

  14. Photo-assisted etching of silicon in chlorine- and bromine-containing plasmas

    SciTech Connect (OSTI)

    Zhu, Weiye; Sridhar, Shyam; Liu, Lei; Hernandez, Eduardo; Donnelly, Vincent M., E-mail: vmdonnelly@uh.edu; Economou, Demetre J., E-mail: economou@uh.edu [Plasma Processing Laboratory, Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204-4004 (United States)

    2014-05-28T23:59:59.000Z

    Cl{sub 2}, Br{sub 2}, HBr, Br{sub 2}/Cl{sub 2}, and HBr/Cl{sub 2} feed gases diluted in Ar (50%–50% by volume) were used to study etching of p-type Si(100) in a rf inductively coupled, Faraday-shielded plasma, with a focus on the photo-assisted etching component. Etching rates were measured as a function of ion energy. Etching at ion energies below the threshold for ion-assisted etching was observed in all cases, with Br{sub 2}/Ar and HBr/Cl{sub 2}/Ar plasmas having the lowest and highest sub-threshold etching rates, respectively. Sub-threshold etching rates scaled with the product of surface halogen coverage (measured by X-ray photoelectron spectroscopy) and Ar emission intensity (7504?Å). Etching rates measured under MgF{sub 2}, quartz, and opaque windows showed that sub-threshold etching is due to photon-stimulated processes on the surface, with vacuum ultraviolet photons being much more effective than longer wavelengths. Scanning electron and atomic force microscopy revealed that photo-etched surfaces were very rough, quite likely due to the inability of the photo-assisted process to remove contaminants from the surface. Photo-assisted etching in Cl{sub 2}/Ar plasmas resulted in the formation of 4-sided pyramidal features with bases that formed an angle of 45° with respect to ?110? cleavage planes, suggesting that photo-assisted etching can be sensitive to crystal orientation.

  15. Miniaturized cathodic arc plasma source

    DOE Patents [OSTI]

    Anders, Andre (Albany, CA); MacGill, Robert A. (Richmond, CA)

    2003-04-15T23:59:59.000Z

    A cathodic arc plasma source has an anode formed of a plurality of spaced baffles which extend beyond the active cathode surface of the cathode. With the open baffle structure of the anode, most macroparticles pass through the gaps between the baffles and reflect off the baffles out of the plasma stream that enters a filter. Thus the anode not only has an electrical function but serves as a prefilter. The cathode has a small diameter, e.g. a rod of about 1/4 inch (6.25 mm) diameter. Thus the plasma source output is well localized, even with cathode spot movement which is limited in area, so that it effectively couples into a miniaturized filter. With a small area cathode, the material eroded from the cathode needs to be replaced to maintain plasma production. Therefore, the source includes a cathode advancement or feed mechanism coupled to cathode rod. The cathode also requires a cooling mechanism. The movable cathode rod is housed in a cooled metal shield or tube which serves as both a current conductor, thus reducing ohmic heat produced in the cathode, and as the heat sink for heat generated at or near the cathode. Cooling of the cathode housing tube is done by contact with coolant at a place remote from the active cathode surface. The source is operated in pulsed mode at relatively high currents, about 1 kA. The high arc current can also be used to operate the magnetic filter. A cathodic arc plasma deposition system using this source can be used for the deposition of ultrathin amorphous hard carbon (a-C) films for the magnetic storage industry.

  16. SENSORLESS INDUCTION MOTOR CONTROL USING STATISTICAL

    E-Print Network [OSTI]

    is replaced by npM so that the dynamic model of the induction motor is then uSa = RSiSa + LS d dtiSa + M d dti

  17. Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for RenewableSpeedingBiomassPPPOPetroleum38 (1996) A213-A225. Printed in the UK4 Plasma

  18. Synchronous Machine Modeling Notes2 1.0 Inductances

    E-Print Network [OSTI]

    McCalley, James D.

    i i LLLLLL LLLLLL LLLLLL LLLLLL LLLLLL LLLLLL (1) We saw there are four blocks: · L11 (stator-stator inductances) · L12 (stator-rotor inductances) · L21 (rotor-stator inductances) · L22 (rotor-rotor inductances the reluctance seen by the flux from the main field winding F, linking with itself, to determine whether LF

  19. An Analysis of Energy Balance in a Helicon Plasma Source for Space Propulsion

    E-Print Network [OSTI]

    An Analysis of Energy Balance in a Helicon Plasma Source for Space Propulsion by Justin Matthew;An Analysis of Energy Balance in a Helicon Plasma Source for Space Propulsion by Justin Matthew Pucci are optical radiation emission, wall losses due to poor magnetic confinement, and poor antenna-plasma coupling

  20. Kinetic effects of non-equilibrium plasma-assisted methane oxidation on diffusion flame extinction limits

    E-Print Network [OSTI]

    Ju, Yiguang

    08544, USA b US Air Force Research Laboratory, Propulsion Directorate, Wright-Patterson AFB, OH 45433 plasma assisted combustion resulted in fast chemical heat release and extended the extinction limits processes in plasma­flame interactions [1­17]. However, plasma assisted combustion involves strong coupling

  1. Coupling coefficients for coupled-cavity lasers

    SciTech Connect (OSTI)

    Lang, R.J.; Yariv, A.

    1987-03-01T23:59:59.000Z

    The authors derive simple, analytic formulas for the field coupling coefficients in a two-section coupled-cavity laser using a local field rate equation treatment. They show that there is a correction to the heuristic formulas based on power flow calculated by Marcuse; the correction is in agreement with numerical calculations from a coupled-mode approach.

  2. Plasma generators, reactor systems and related methods

    DOE Patents [OSTI]

    Kong, Peter C. (Idaho Falls, ID); Pink, Robert J. (Pocatello, ID); Lee, James E. (Idaho Falls, ID)

    2007-06-19T23:59:59.000Z

    A plasma generator, reactor and associated systems and methods are provided in accordance with the present invention. A plasma reactor may include multiple sections or modules which are removably coupled together to form a chamber. Associated with each section is an electrode set including three electrodes with each electrode being coupled to a single phase of a three-phase alternating current (AC) power supply. The electrodes are disposed about a longitudinal centerline of the chamber and are arranged to provide and extended arc and generate an extended body of plasma. The electrodes are displaceable relative to the longitudinal centerline of the chamber. A control system may be utilized so as to automatically displace the electrodes and define an electrode gap responsive to measure voltage or current levels of the associated power supply.

  3. Apparatus for recording emissions from a rapidly generated plasma from a single plasma producing event

    DOE Patents [OSTI]

    Tan, Tai Ho (Los Alamos, NM); Williams, Arthur H. (Los Alamos, NM)

    1985-01-01T23:59:59.000Z

    An optical fiber-coupled detector visible streak camera plasma diagnostic apparatus. Arrays of optical fiber-coupled detectors are placed on the film plane of several types of particle, x-ray and visible spectrometers or directly in the path of the emissions to be measured and the output is imaged by a visible streak camera. Time and spatial dependence of the emission from plasmas generated from a single pulse of electromagnetic radiation or from a single particle beam burst can be recorded.

  4. Instabilities in Zakharov Equations for Laser Propagation in a Plasma

    E-Print Network [OSTI]

    Colin, Thierry

    have to be coupled in order to take into account the laser beam, the Raman component and the electronic in a laboratory nuclear fusion by inertial confinement. This requires precise and reliable models for laser electronic plasma waves. These systems couple the slowly varying envelope of the electric field and the low

  5. Rigorous theory of nuclear fusion rates in a plasma

    E-Print Network [OSTI]

    Lowell S. Brown; David C. Dooling; Dean L. Preston

    2005-09-22T23:59:59.000Z

    Real-time thermal field theory is used to reveal the structure of plasma corrections to nuclear reactions. Previous results are recovered in a fashion that clarifies their nature, and new extensions are made. Brown and Yaffe have introduced the methods of effective quantum field theory into plasma physics. They are used here to treat the interesting limiting case of dilute but very highly charged particles reacting in a dilute, one-component plasma. The highly charged particles are very strongly coupled to this background plasma. The effective field theory proves that this mean field solution plus the one-loop term dominate; higher loop corrections are negligible even though the problem involves strong coupling. Such analytic results for very strong coupling are rarely available, and they can serve as benchmarks for testing computer models.

  6. How to model quantum plasmas

    E-Print Network [OSTI]

    G. Manfredi

    2005-05-01T23:59:59.000Z

    Traditional plasma physics has mainly focused on regimes characterized by high temperatures and low densities, for which quantum-mechanical effects have virtually no impact. However, recent technological advances (particularly on miniaturized semiconductor devices and nanoscale objects) have made it possible to envisage practical applications of plasma physics where the quantum nature of the particles plays a crucial role. Here, I shall review different approaches to the modeling of quantum effects in electrostatic collisionless plasmas. The full kinetic model is provided by the Wigner equation, which is the quantum analog of the Vlasov equation. The Wigner formalism is particularly attractive, as it recasts quantum mechanics in the familiar classical phase space, although this comes at the cost of dealing with negative distribution functions. Equivalently, the Wigner model can be expressed in terms of $N$ one-particle Schr{\\"o}dinger equations, coupled by Poisson's equation: this is the Hartree formalism, which is related to the `multi-stream' approach of classical plasma physics. In order to reduce the complexity of the above approaches, it is possible to develop a quantum fluid model by taking velocity-space moments of the Wigner equation. Finally, certain regimes at large excitation energies can be described by semiclassical kinetic models (Vlasov-Poisson), provided that the initial ground-state equilibrium is treated quantum-mechanically. The above models are validated and compared both in the linear and nonlinear regimes.

  7. Principle of Mathematical Induction (PMI) Statement of the Principle of Mathematical Induction

    E-Print Network [OSTI]

    Singman, David

    Principle of Mathematical Induction (PMI) Statement of the Principle of Mathematical Induction Let you have a subset S of N which you wish to prove is all of N. If you use PMI, the proof can be written as follows. Outline of a proof by PMI Proof. We prove this result using PMI. Let S = . . . (describe the set

  8. Plasma momentum meter for momentum flux measurements

    DOE Patents [OSTI]

    Zonca, F.; Cohen, S.A.; Bennett, T.; Timberlake, J.R.

    1993-08-24T23:59:59.000Z

    An apparatus is described for measuring momentum flux from an intense plasma stream, comprising: refractory target means oriented normal to the flow of said plasma stream for bombardment by said plasma stream where said bombardment by said plasma stream applies a pressure to said target means, pendulum means for communicating a translational displacement of said target to a force transducer where said translational displacement of said target is transferred to said force transducer by an elongated member coupled to said target, where said member is suspended by a pendulum configuration means and where said force transducer is responsive to said translational displacement of said member, and force transducer means for outputting a signal representing pressure data corresponding to said displacement.

  9. Internal Heat Transfer Coefficient Determination in a Packed Bed From the Transient Response Due to Solid Phase Induction Heating

    E-Print Network [OSTI]

    Geb, David; Zhou, Feng; Catton, Ivan

    2012-01-01T23:59:59.000Z

    to Solid Phase Induction Heating Nonintrusive measurementsgeneration rate via induction heating. The fluid temperaturetechnique, induction heating, bypass effect, channeling

  10. A plasma process monitor/control system

    SciTech Connect (OSTI)

    Stevenson, J.O.; Ward, P.P.; Smith, M.L. [Sandia National Labs., Albuquerque, NM (United States); Markle, R.J. [Advanced Micro Devices, Inc., Austin, TX (United States)

    1997-08-01T23:59:59.000Z

    Sandia National Laboratories has developed a system to monitor plasma processes for control of industrial applications. The system is designed to act as a fully automated, sand-alone process monitor during printed wiring board and semiconductor production runs. The monitor routinely performs data collection, analysis, process identification, and error detection/correction without the need for human intervention. The monitor can also be used in research mode to allow process engineers to gather additional information about plasma processes. The plasma monitor can perform real-time control of support systems known to influence plasma behavior. The monitor can also signal personnel to modify plasma parameters when the system is operating outside of desired specifications and requires human assistance. A notification protocol can be selected for conditions detected in the plasma process. The Plasma Process Monitor/Control System consists of a computer running software developed by Sandia National Laboratories, a commercially available spectrophotometer equipped with a charge-coupled device camera, an input/output device, and a fiber optic cable.

  11. Polished Downhole Transducer Having Improved Signal Coupling

    DOE Patents [OSTI]

    Hall, David R. (Provo, UT); Fox, Joe (Spanish Fork, UT)

    2006-03-28T23:59:59.000Z

    Apparatus and methods to improve signal coupling in downhole inductive transmission elements to reduce the dispersion of magnetic energy at the tool joints and to provide consistent impedance and contact between transmission elements located along the drill string. A transmission element for transmitting information between downhole tools is disclosed in one embodiment of the invention as including an annular core constructed of a magnetically conductive material. The annular core forms an open channel around its circumference and is configured to form a closed channel by mating with a corresponding annular core along an annular mating surface. The mating surface is polished to provide improved magnetic coupling with the corresponding annular core. An annular conductor is disposed within the open channel.

  12. Anomalous radial transport in tokamak edge plasma

    E-Print Network [OSTI]

    Bodi, Vasudeva Raghavendra Kowsik

    2010-01-01T23:59:59.000Z

    Transport in tokamak plasma . . . . . . . . . . . . . . .Numerical simulations of tokamak plasma . . . . . . . . .of blobs in tokamak edge plasmas . . . . . . . . . . . . . .

  13. Plasma PhysicsPlasma Physics Atoms Beams and PlasmasAtoms Beams and Plasmas

    E-Print Network [OSTI]

    Strathclyde, University of

    of plasma research and understanding their dynamics is cutting edge topic in physics Small instabilities

  14. Induction linacs for heavy ion fusion research

    SciTech Connect (OSTI)

    Fessenden, T.J.

    1984-05-01T23:59:59.000Z

    The new features of employing an induction linac as a driver for inertial fusion involve (1) transport of high-current low-emittance heavy ion beams, (2) multiple independently-focussed beams threading the same accelerator structure, and (3) synthesis of voltage waveforms to accomplish beam current amplification. A research program is underway at LBL to develop accelerators that test all these features with the final goal of producing an ion beam capable of heating matter to approx. 70 eV. This paper presents a discussion of some properties of induction linacs and how they may be used for HIF research. Physics designs of the High Temperature Experiment (HTE) and the Multiple Beam Experiment (MBE) accelerators are presented along with initial concepts of the MBE induction units.

  15. Toroidal midplane neutral beam armor and plasma limiter

    DOE Patents [OSTI]

    Kugel, Henry W. (Somerset, NJ); Hand, Jr, Samuel W. (Hopewell Township, Mercer County, NJ); Ksayian, Haig (Titusville, NJ)

    1986-01-01T23:59:59.000Z

    For use in a tokamak fusion reactor having a midplane magnetic coil on the inner wall of an evacuated toriodal chamber within which a neutral beam heated, fusing plasma is magnetically confined, a neutral beam armor shield and plasma limiter is provided on the inner wall of the toroidal chamber to shield the midplane coil from neutral beam shine-thru and plasma deposition. The armor shield/plasma limiter forms a semicircular enclosure around the midplane coil with the outer surface of the armor shield/plasma limiter shaped to match, as closely as practical, the inner limiting magnetic flux surface of the toroidally confined, indented, bean-shaped plasma. The armor shield/plasma limiter includes a plurality of semicircular graphite plates each having a pair of coupled upper and lower sections with each plate positioned in intimate contact with an adjacent plate on each side thereof so as to form a closed, planar structure around the entire outer periphery of the circular midplane coil. The upper and lower plate sections are adapted for coupling to heat sensing thermocouples and to a circulating water conduit system for cooling the armor shield/plasma limiter.The inner center portion of each graphite plate is adapted to receive and enclose a section of a circular diagnostic magnetic flux loop so as to minimize the power from the plasma confinement chamber incident upon the flux loop.

  16. Inductive gas line for pulsed lasers

    DOE Patents [OSTI]

    Benett, William J. (Livermore, CA); Alger, Terry W. (Tracy, CA)

    1985-01-01T23:59:59.000Z

    A gas laser having a metal inlet gas feed line assembly shaped as a coil, to function as an electrical inductance and therefore high impedance to pulses of electric current applied to electrodes at opposite ends of a discharge tube of a laser, for example. This eliminates a discharge path for the laser through the inlet gas feed line. A ferrite core extends through the coil to increase the inductance of the coil and provide better electric isolation. By elimination of any discharge breakdown through the gas supply, efficiency is increased and a significantly longer operating lifetime of the laser is provided.

  17. Inductive gas line for pulsed lasers

    DOE Patents [OSTI]

    Benett, W.J.; Alger, T.W.

    1982-09-29T23:59:59.000Z

    A gas laser having a metal inlet gas feed line assembly shaped as a coil, to function as an electrical inductance and therefore high impedance to pulses of electric current applied to electrodes at opposite ends of a discharge tube of a laser, for example. This eliminates a discharge path for the laser through the inlet gas feed line. A ferrite core extends through the coil to increase the inductance of the coil and provide better electric isolation. By elimination of any discharge breakdown through the gas supply, efficiency is increased and a significantly longer operating lifetime of the laser is provided.

  18. Nonplanar solitons collision in ultracold neutral plasmas

    SciTech Connect (OSTI)

    El-Tantawy, S. A.; Moslem, W. M.; El-Metwally, M. [Department of Physics, Faculty of Science, Port Said University, Port Said 42521 (Egypt)] [Department of Physics, Faculty of Science, Port Said University, Port Said 42521 (Egypt); Sabry, R. [Theoretical Physics Group, Department of Physics, Faculty of Science, Damietta University, New Damietta 34517 (Egypt) [Theoretical Physics Group, Department of Physics, Faculty of Science, Damietta University, New Damietta 34517 (Egypt); Department of Physics, College of Science and Humanitarian Studies, Salman Bin Abdulaziz University, Alkharj (Saudi Arabia); El-Labany, S. K. [Theoretical Physics Group, Department of Physics, Faculty of Science, Damietta University, New Damietta 34517 (Egypt)] [Theoretical Physics Group, Department of Physics, Faculty of Science, Damietta University, New Damietta 34517 (Egypt); Schlickeiser, R. [Institut für Theoretische Physik, Lehrstuhl IV: Weltraum- und Astrophysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany)] [Institut für Theoretische Physik, Lehrstuhl IV: Weltraum- und Astrophysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany)

    2013-09-15T23:59:59.000Z

    Collisions between two nonplanar ion-acoustic solitons in strongly coupled ultracold neutral plasmas composed of ion fluid and non-Maxwellian (nonthermal or superthermal) electron distributions are investigated. The extended Poincare-Lighthill-Kuo method is used to obtain coupled nonplanar Kortweg-de Vries equations for describing the system. The nonplanar phase shifts after the interaction of the two solitons are calculated. It is found that the properties of the nonplanar colliding solitons and its corresponding phase shifts are different from those in the planar case. The polarity of the colliding solitons strongly depends on the type of the non-Maxwellian electron distributions. A critical nonthermality parameter ?{sub c} is identified. For values of ? ? ?{sub c} solitons with double polarity exist, while this behavior cannot occur for superthermal plasmas. The phase shift for nonthermal plasmas increases below ?{sub c} for a positive soliton, but it decreases for ? > ?{sub c} for a negative soliton. For superthermal plasmas, the phase shift enhances rapidly for low values of spectral index ? and higher values of ions effective temperature ratio ?{sub *}. For 2 ? ?<10, the phase shift decreases but does not change for ? > 10. The nonlinear structure, as reported here, is useful for controlling the solitons created in forthcoming ultracold neutral plasma experiments.

  19. The Absence of Plasma in "Spark Plasma Sintering"

    E-Print Network [OSTI]

    Hulbert, Dustin M.

    2008-01-01T23:59:59.000Z

    investigations on the spark plasma sintering/synthesisinvestigations on the spark plasma sintering/synthesisenhancement in spark-plasma sintering: Impact of high

  20. Cooling a quantum circuit via coupling to a multiqubit system

    E-Print Network [OSTI]

    Mihai A. Macovei

    2010-04-19T23:59:59.000Z

    The cooling effects of a quantum LC circuit coupled inductively with an ensemble of artificial qubits are investigated. The particles may decay independently or collectively through their interaction with the environmental vacuum electromagnetic field reservoir. For appropriate bath temperatures and the resonator's quality factors, we demonstrate an effective cooling well below the thermal background. In particular, we found that for larger samples the cooling efficiency is better for independent qubits. However, the cooling process can be faster for collectively interacting particles.

  1. Low pass filter for plasma discharge

    DOE Patents [OSTI]

    Miller, Paul A. (Albuquerque, NM)

    1994-01-01T23:59:59.000Z

    An isolator is disposed between a plasma reactor and its electrical energy source in order to isolate the reactor from the electrical energy source. The isolator operates as a filter to attenuate the transmission of harmonics of a fundamental frequency of the electrical energy source generated by the reactor from interacting with the energy source. By preventing harmonic interaction with the energy source, plasma conditions can be readily reproduced independent of the electrical characteristics of the electrical energy source and/or its associated coupling network.

  2. High School Science Teacher Induction in Texas: Implications for Policy

    E-Print Network [OSTI]

    Ivey, Toni Ann

    2011-02-22T23:59:59.000Z

    principals' perceptions of teacher induction. Analyses indicated that high school principals had an overwhelmingly narrow focus of mentoring and provided mentor teachers with little support or training. Findings indicated that induction activities...

  3. Excitation and control of a high-speed induction generator

    E-Print Network [OSTI]

    Englebretson, Steven Carl

    2005-01-01T23:59:59.000Z

    This project investigates the use of a high speed, squirrel cage induction generator and power converter for producing DC electrical power onboard ships and submarines. Potential advantages of high speed induction generators ...

  4. Semantic Taxonomy Induction from Heterogenous Evidence Computer Science Department

    E-Print Network [OSTI]

    Ng, Andrew Y.

    Semantic Taxonomy Induction from Heterogenous Evidence Rion Snow Computer Science Department­ tic taxonomies. Previous algorithms for taxonomy induction have typically focused on independent over heterogenous relationships to optimize the entire structure of the taxonomy, using knowl­ edge

  5. Semantic Taxonomy Induction from Heterogenous Evidence Computer Science Department

    E-Print Network [OSTI]

    Ng, Andrew Y.

    Semantic Taxonomy Induction from Heterogenous Evidence Rion Snow Computer Science Department- tic taxonomies. Previous algorithms for taxonomy induction have typically focused on independent over heterogenous relationships to optimize the entire structure of the taxonomy, using knowl- edge

  6. advanced induction machine: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Adjustable speed generationDynamic Phasor Modeling of the Doubly-Fed Induction Machine in Generator Operation Emmanuel 617 373 8970 Abstract-- The doubly-fed induction machine used...

  7. Inductive Effect of Alkyl Chains on Alcohol Dehydration at Bridge...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Inductive Effect of Alkyl Chains on Alcohol Dehydration at Bridge-Bonded Oxygen Vacancies of TiO2(110). Inductive Effect of Alkyl Chains on Alcohol Dehydration at Bridge-Bonded...

  8. Magnetic induction systems to harvest energy from mechanical vibrations

    E-Print Network [OSTI]

    Jonnalagadda, Aparna S

    2007-01-01T23:59:59.000Z

    This thesis documents the design process for magnetic induction systems to harvest energy from mechanical vibrations. Two styles of magnetic induction systems - magnet-through-coil and magnet-across-coils - were analyzed. ...

  9. Pulsed inductive thruster performance data base for megawatt-class engine applications

    SciTech Connect (OSTI)

    Dailey, C.L. (TRW Space and Technology Group, One Pace Park, Redondo Beach, CA 90278 (United States)); Lovberg, R.H. (University of California at San Diego, 4744 Panorama Drive, San Diego, CA 92116 (United States))

    1993-01-20T23:59:59.000Z

    The pulsed inductive thruster (PIT) is an electrodeless plasma accelerator employing a large (1m diameter) spiral coil energized by a capacitor bank discharge. The bank can be repetitively recharged by a nuclear electric generator for continuous MW level operation. The coil can be designed as a transformer that permits thruster operation at the generator voltage, which results in a low thruster specific mass. Specific impulse ([ital I][sub sp]) can be readily altered by changing the propellant valve plenum pressure. Performance curves generated from mesausred impulse, injected mass and capacitor bank energy are presented for argon, ammonia, hydrazine, carbon dioxide and helium. The highest performance measured to date is 48% efficiency at 4000 seconds [ital I][sub sp] with ammonia. The development of a theoretical model of the thruster, which assumes a fully ionized plasma, is presented in an appendix.

  10. ACTIONS AND PARTIAL ACTIONS OF INDUCTIVE CONSTELLATIONS

    E-Print Network [OSTI]

    Gould, Victoria

    ACTIONS AND PARTIAL ACTIONS OF INDUCTIVE CONSTELLATIONS VICTORIA GOULD AND CHRISTOPHER HOLLINGS structure of a semigroup can be recovered from a partial order it possesses. Date: August 13, 2009. 2000 and FEDER, and also FCT post-doctoral grant SFRH/BPD/34698/2007. 1 #12;2 VICTORIA GOULD AND CHRISTOPHER

  11. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, William M. (Santa Fe, NM)

    1992-01-01T23:59:59.000Z

    Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance.

  12. Induction Motors Bearing Failures Detection and Diagnosis

    E-Print Network [OSTI]

    Boyer, Edmond

    using the mains current and the rotor speed measurement. The proposed approach is based on the stator current Park patterns. Induction motor stator currents are measured, recorded and used for Park patterns detection and diagnosis process. Experimental tests with artificial bearing damages results show

  13. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, W.M.

    1992-12-29T23:59:59.000Z

    Improvement in voltage regulation in a linear induction accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core is disclosed. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance. 4 figs.

  14. Ising interaction between capacitively-coupled superconducting flux qubits

    E-Print Network [OSTI]

    Takahiko Satoh; Yuichiro Matsuzaki; Kosuke Kakuyanagi; Koichi Semba; Hiroshi Yamaguchi; Shiro Saito

    2015-01-30T23:59:59.000Z

    Here, we propose a scheme to generate a controllable Ising interaction between superconducting flux qubits. Existing schemes rely on inducting couplings to realize Ising interactions between flux qubits, and the interaction strength is controlled by an applied magnetic field On the other hand, we have found a way to generate an interaction between the flux qubits via capacitive couplings. This has an advantage in individual addressability, because we can control the interaction strength by changing an applied voltage that can be easily localized. This is a crucial step toward the realizing superconducting flux qubit quantum computation.

  15. Global parameter optimization of Mather type plasma focus in the framework of the Gratton-Vargas two-dimensional snowplow model

    E-Print Network [OSTI]

    Auluck, S K H

    2014-01-01T23:59:59.000Z

    Dense Plasma Focus (DPF) is known to produce highly energetic ions, electrons and plasma environment which can be used for breeding of short-lived isotopes, plasma nanotechnology and other material processing applications. Commercial utilization of DPF in such areas would need a design tool which can be deployed in an automatic search for the best possible device configuration for a given application. The recently revisited [S K H Auluck, Physics of Plasmas 20, 112501 (2013)] Gratton-Vargas (GV) two-dimensional analytical snowplow model of plasma focus provides a numerical formula for dynamic inductance of a Mather type plasma focus fitted to thousands of automated computations, which enables construction of such design tool. This inductance formula is utilized in the present work to explore global optimization, based on first-principles optimality criteria, in a 4-dimensional parameter-subspace of the zero-resistance GV model. The optimization process is shown to reproduce the empirically observed constancy ...

  16. Charge exchange and ionization cross sections of H{sup +}+H collision in dense quantum plasmas

    SciTech Connect (OSTI)

    Zhang, Ling-yu; Qi, Xin; Zhao, Xiao-ying; Meng, Dong-yuan; Xiao, Guo-qing [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China and University of Chinese Academy of Sciences, Beijing 100049 (China)] [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China and University of Chinese Academy of Sciences, Beijing 100049 (China); Duan, Wen-shan [Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou, Gansu 730070 (China)] [Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou, Gansu 730070 (China); Yang, Lei [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China and University of Chinese Academy of Sciences, Beijing 100049 (China) [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China and University of Chinese Academy of Sciences, Beijing 100049 (China); Department of Physics, Lanzhou University, Lanzhou 730000 (China)

    2013-11-15T23:59:59.000Z

    The plasma screening effects of dense quantum plasmas on H{sup +}+H charge exchange and ionization cross sections are calculated by the classical trajectory Monte Carlo method. For charge exchange cross sections, it is found that the screening effects reduce cross sections slightly in weak screening conditions. However, cross sections are reduced substantially in strong screening conditions. For ionization cross sections, with the increase of screening effects, cross sections for low energies increase more rapidly than those for high energies. When the screening effects are strong enough, it is found that ionization cross sections decrease with the increase of incident H{sup +} energy. In addition, the cross sections have been compared with those in weakly coupled plasmas. It is found that in weak screening conditions, plasma screening effects in the two plasmas are approximately the same, while in strong screening conditions, screening effects of dense quantum plasmas are stronger than those of weakly coupled plasmas.

  17. 92 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 30, NO. 1, FEBRUARY 2002 Formation of Coulomb Crystals in a

    E-Print Network [OSTI]

    Kushner, Mark

    sheaths. DUST PARTICLE transport in partially ionized plasmas has been the focus of many recent92 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 30, NO. 1, FEBRUARY 2002 Formation of Coulomb Crystals in a Capacitively Coupled Plasma Vivek Vyas and Mark J. Kushner, Fellow, IEEE Abstract--Dust particle transport

  18. Abatement of 3-methylbutanal and trimethylamine with combined plasma1 and photocatalysisin a continuous planar reactor2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    plasma discharge coupled with photocatalysis. The capability of this18 process for gas treatmentwas was observedby combining26 plasma SDBD and photocatalysis from all experiments and with other pollutant such as27, photocatalysis and plasma SDBD/photocatalysis combination.29 30 Keywords:31 32 Synergetic effect; planar reactor

  19. Coupled modes analysis of SRS backscattering, with Langmuir decay and possible cascadings

    E-Print Network [OSTI]

    Salcedo, Ante, 1969-

    2002-01-01T23:59:59.000Z

    Recent experiments aimed at understanding stimulated Raman scattering (SRS) in ICF laser-plasma interactions, suggest that SRS is coupled to the Langmuir decay interaction (LDI). The effects of LDI on the saturation of the ...

  20. Characterization of Nickel and Vanadium compounds in tar sand bitumen by petroporphyrin quantitation and size exclusion chromatography coupled with element specific detection

    SciTech Connect (OSTI)

    Reynolds, J.G.; Jones, E.L.; Bennett, J.A.; Biggs, W.R.

    1988-06-01T23:59:59.000Z

    Tar sands represent a tremendous untapped resource for transportation fuels. In the United States alone, over 60 billion barrels of bitumen are estimated to be in place. In order to use this bitumen, it must be somehow separated from the sand. The resulting bitumen is of low quality, and generally will require at least some refining. Typical refinery upgrading methods include fluid catalytic cracking, thermal visbreaking, and residuum hydroconversion. Most of these methods utilize metals-sensitive catalyst. The metals bound in the bitumen are deleterious to catalytic processing, causing rapid deactivation through poisoning and pore mouth plugging. Like heavy crude oil residua, tar sand bitumens have high concentrations of Ni and V. The types of complexes of Ni and V have been studied for heavy crude oils, and can be placed in two broad categories: the metallopetroporphyrins and the metallononporphyrins. The metallopetroporphyrins have been studied extensively. For understanding the behavior of the metals in processing, size exclusion chromatography coupled with element specific detection by inductively coupled plasma atomic emission spectroscopy (SEC-HPLC-ICP) has been applied to several heavy crude oils, residua, and processed products along with separated fractions of feeds and products. These results have shown general important size-behavior features of the metallopetroporphyrins and metallo-nonporphyrins associated with individual feed characteristics. Because of the importance of the metals in a downstream process methods, the authors have applied several of the metallopetroporphyrin and metallo-nonporphyrin examination technique to extracted bitumen from selected tar sands.

  1. Ionization rate coefficients and induction times in nitrogen at high values of E/N

    SciTech Connect (OSTI)

    Hays, G.N.; Pitchford, L.C.; Gerardo, J.B.; Verdeyen, J.T.; Li, Y.M.

    1987-09-01T23:59:59.000Z

    Electron-impact ionization rate coefficients in nitrogen at values of E/N, the ratio of the electric field to the neutral density, up to 12 000 Td (1 Td = 10/sup -17/ V cmS), are reported. In addition, we report experimental measurements of the ionization induction time, the time during the early portion of an applied electric field when the electron energy distribution function is transient and the plasma is characterized by nonexponential growth of the electron density. For nitrogen, we show that the induction period is approximately equal to the inverse of the ionization frequency for a large E/N range. Time-dependent Boltzmann calculations of the electron energy distribution function yield instantaneous ionization rates that are in good agreement with both the measured ionization rates and the induction period. The measurements were made in an electrodeless cell contained in an S-band waveguide immersed in a dc magnetic field and subjected to a pulsed rf electric field at cyclotron resonance. We show that our measurements are equivalent to experiments in dc electric fields; the equivalent dc electric field strength being uniquely related to the rf electric field strength. The use of an rf field for these high-E/N measurements circumvents complications that would be introduced by electrode effects. This is the first direct measurement of ionization rates at these extreme values of E/N.

  2. Wake of a heavy quark in non-Abelian plasmas: Comparing kinetic theory and the anti-de Sitter space/conformal field theory correspondence

    E-Print Network [OSTI]

    Hong, Juhee

    We compute the nonequilibrium stress tensor induced by a heavy quark moving through weakly coupled QCD plasma at the speed of light and compare the result to N=4 super-Yang-Mills theory at strong coupling. The QCD Boltzmann ...

  3. A new low-frequency backward mode in inhomogeneous plasmas

    SciTech Connect (OSTI)

    Vranjes, J., E-mail: jvranjes@yahoo.com [Institute of Physics, Pregrevica 118, 11080 Zemun, Belgrade (Serbia)

    2014-07-15T23:59:59.000Z

    When an electromagnetic transverse wave propagates through an inhomogeneous plasma so that its electric field has a component in the direction of the background density gradient, there appears a disbalance of charge in every plasma layer, caused by the density gradient. Due to this, some additional longitudinal electric field component appears in the direction of the wave vector. This longitudinal field may couple with the usual electrostatic longitudinal perturbations like the ion acoustic, electron Langmuir, and ion plasma waves. As a result, these standard electrostatic waves are modified and in addition to this a completely new low-frequency mode appears. Some basic features of the coupling and modification of the ion acoustic wave, and properties of the new mode are discussed here, in ordinary electron-ion and in pair plasmas.

  4. oxygen-plasma | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    oxygen-plasma oxygen-plasma Leads No leads are available at this time. Conversion of 1,2-Propylene Glycol on Rutile TiO2(110). Abstract: We have studied the reactions of...

  5. Relaxation time of non-conformal plasma

    E-Print Network [OSTI]

    Alex Buchel

    2009-11-27T23:59:59.000Z

    We study effective relaxation time of viscous hydrodynamics of strongly coupled non-conformal gauge theory plasma using gauge theory/string theory correspondence. We compute leading corrections to the conformal plasma relaxation time from the relevant deformations due to dim-2 and dim-3 operators. We discuss in details the relaxation time tau_eff of N=2^* plasma. For a certain choice of masses this theory undergoes a phase transition with divergent specific heat c_V ~ |1-T_c/T|^(-1/2). Although the bulk viscosity remains finite all the way to the critical temperature, we find that tau_eff diverges near the critical point as tau_eff ~ |1-T_c/T|^(-1/2).

  6. INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 16 (2007) 9096 doi:10.1088/0963-0252/16/1/012

    E-Print Network [OSTI]

    Economou, Demetre J.

    2007-01-01T23:59:59.000Z

    -dimensional simulation of the plasma reactor was coupled with a two-dimensional simulation of the sheath region overIEDisdeterminedbythedifferenceinpotentialbetweenthe plasma and the substrate, as well as ion collisions with the background neutral gas. For radio frequency were then neutralized to become fast neutrals in neutral beam applications [12,13]. In all

  7. Effect of trapping in degenerate quantum plasmas

    SciTech Connect (OSTI)

    Shah, H. A.; Qureshi, M. N. S. [Department of Physics, GC University, Lahore 54000 (Pakistan); Tsintsadze, N. [Department of Physics, GC University, Lahore 54000 (Pakistan); Salam Chair, GC University, Lahore 54000 (Pakistan)

    2010-03-15T23:59:59.000Z

    In the present work we consider the effect of trapping as a microscopic process in a plasma consisting of quantum electrons and nondegenerate ions. The formation of solitary structures is investigated in two cases: first when the electrons are fully degenerate and second when small temperature effects are taken into account. It is seen that not only rarefactive but coupled rarefactive and compressive solitons are obtained under different temperature conditions.

  8. Tape-Drive Based Plasma Mirror

    SciTech Connect (OSTI)

    Sokollik, Thomas; Shiraishi, Satomi; Osterhoff, Jens; Evans, Eugene; Gonsalves, Anthony; Nakamura, Kei; vanTilborg, Jeroen; Lin, Chen; Toth, Csaba; Leemans, Wim

    2011-07-22T23:59:59.000Z

    We present experimental results on a tape-drive based plasma mirror which could be used for a compact coupling of a laser beam into a staged laser driven electron accelerator. This novel kind of plasma mirror is suitable for high repetition rates and for high number of laser shots. In order to design a compact, staged laser plasma based accelerator or collider [1], the coupling of the laser beam into the different stages represents one of the key issues. To limit the spatial foot print and thus to realize a high overall acceleration gradient, a concept has to be found which realizes this in-coupling within a few centimeters (cf. Fig 1). The fluence of the laser pulse several centimeters away from the acceleration stage (focus) exceeds the damage threshold of any available mirror coating. Therefore, in reference [2] a plasma mirror was suggested for this purpose. We present experiments on a tape-drive based plasma mirror which could be used to reflect the focused laser beam into the acceleration stage. Plasma mirrors composed of antireflection coated glass substrates are usually used to improve the temporal laser contrast of laser pulses by several orders of magnitudes [3,4]. This is particularly important for laser interaction with solid matter, such as ion acceleration [5,6] and high harmonic generation on surfaces [7]. Therefore, the laser pulse is weekly focused onto a substrate. The main pulse generates a plasma and is reflected at the critical surface, whereas the low intensity pre-pulse (mainly the Amplified Spontaneous Emission pedestal) will be transmitted through the substrate before the mirror has been triggered. Several publications [3,4] demonstrate a conservation of the spatial beam quality and a reflectivity of about 70 %. The drawback of this technique is the limited repetition rate since for every shot a fresh surface has to be provided. In the past years several novel approaches for high repetition rate plasma mirrors have been developed [2, 8]. Nevertheless, for the staged accelerator scheme a second important requirement has to be considered. Since the electron beam has to propagate through the mirror, the thickness of the substrate has to be as thin as possible to reduce the distortion of the electron beam. A tape of only several micrometer thickness can overcome these disadvantages. It can be used with a sufficient repetition rate while it allows the electron beam to propagate through with a minimum of scattering.

  9. Thermionic energy conversion plasmas

    SciTech Connect (OSTI)

    Rasor, N.S. (Rasor Associates, Inc., Sunnyvale, CA (United States))

    1991-12-01T23:59:59.000Z

    In this paper the history, application options, and ideal basic performance of the thermionic energy converter are outlined. The basic plasma types associated with various modes of converter operation are described, with emphasis on identification and semi-quantitative characterization of the dominant physical processes and utility of each plasma type. The frontier plasma science issues in thermionic converter applications are briefly summarized.

  10. Thermal distributions in stellar plasmas, nuclear reactions and solar neutrinos

    E-Print Network [OSTI]

    M. Coraddu; G. Kaniadakis; A. Lavagno; M. Lissia; G. Mezzorani; P. Quarati

    1998-11-24T23:59:59.000Z

    The physics of nuclear reactions in stellar plasma is reviewed with special emphasis on the importance of the velocity distribution of ions. Then the properties (density and temperature) of the weak-coupled solar plasma are analysed, showing that the ion velocities should deviate from the Maxwellian distribution and could be better described by a weakly-nonexstensive (|q-1|solar neutrino fluxes, and on the pp neutrino energy spectrum, and analyse the consequences for the solar neutrino problem.

  11. Niobium Silicon alloys for Kinetic Inductance Detectors

    E-Print Network [OSTI]

    Calvo, M; Monfardini, A; Benoit, A; Boudou, N; Bourrion, O; Catalano, A; Dumoulin, L; Goupy, J; Sueur, H Le; Marnieros, S

    2013-01-01T23:59:59.000Z

    We are studying the properties of Niobium Silicon amorphous alloys as a candidate material for the fabrication of highly sensitive Kinetic Inductance Detectors (KID), optimized for very low optical loads. As in the case of other composite materials, the NbSi properties can be changed by varying the relative amounts of its components. Using a NbSi film with T_c around 1 K we have been able to obtain the first NbSi resonators, observe an optical response and acquire a spectrum in the band 50 to 300 GHz. The data taken show that this material has very high kinetic inductance and normal state surface resistivity. These properties are ideal for the development of KID. More measurements are planned to further characterize the NbSi alloy and fully investigate its potential.

  12. Lithium Surface Coatings for Improved Plasma Performance in NSTX

    SciTech Connect (OSTI)

    Kugel, H W; Ahn, J -W; Allain, J P; Bell, R; Boedo, J; Bush, C; Gates, D; Gray, T; Kaye, S; Kaita, R; LeBlanc, B; Maingi, R; Majeski, R; Mansfield, D; Menard, J; Mueller, D; Ono, M; Paul, S; Raman, R; Roquemore, A L; Ross, P W; Sabbagh, S; Schneider, H; Skinner, C H; Soukhanovskii, V; Stevenson, T; Timberlake, J; Wampler, W R

    2008-02-19T23:59:59.000Z

    NSTX high-power divertor plasma experiments have shown, for the first time, significant and frequent benefits from lithium coatings applied to plasma facing components. Lithium pellet injection on NSTX introduced lithium pellets with masses 1 to 5 mg via He discharges. Lithium coatings have also been applied with an oven that directed a collimated stream of lithium vapor toward the graphite tiles of the lower center stack and divertor. Lithium depositions from a few mg to 1 g have been applied between discharges. Benefits from the lithium coating were sometimes, but not always seen. These improvements sometimes included decreases plasma density, inductive flux consumption, and ELM frequency, and increases in electron temperature, ion temperature, energy confinement and periods of MHD quiescence. In addition, reductions in lower divertor D, C, and O luminosity were measured.

  13. Strongly coupled plasmas and the QCD critical point

    E-Print Network [OSTI]

    Athanasiou, Christiana

    2011-01-01T23:59:59.000Z

    In this thesis, we begin by studying selected fluctuation observables in order to locate the QCD critical point in heavy-ion collision experiments. In particular, we look at the non-monotonic behavior as a function of the ...

  14. A HIGH REPETITION PLASMA MIRROR FOR STAGED ELECTRON ACCELERATION

    SciTech Connect (OSTI)

    Sokollik, Thomas; Shiraishi, Satomi; Osterhoff, Jens; Evans, Eugene; Gonsalves, Anthony; Nakamura, Kei; vanTilborg, Jeroen; Lin, Chen; Toth, Csaba; Leemans, Wim

    2011-07-22T23:59:59.000Z

    In order to build a compact, staged laser plasma accelerator the in-coupling of the laser beam to the different stages represents one of the key issues. To limit the spatial foot print and thus to realize a high overall acceleration gradient, a concept has to be found which realizes this in-coupling within a few centimeters. We present experiments on a tape-drive based plasma mirror which could be used to reflect the focused laser beam into the acceleration stage.

  15. Acoustic stabilization of electric arc instabilities in nontransferred plasma torches

    SciTech Connect (OSTI)

    Rat, V.; Coudert, J. F. [CNRS, University of Limoges, SPTCS UMR6638, 123 Avenue A. Thomas, 87060 Limoges Cedex (France)

    2010-03-08T23:59:59.000Z

    Electric arc instabilities in dc plasma torches lead to nonhomogeneous treatments of nanosized solid particles or liquids injected within thermal plasma jets. This paper shows that an additional acoustic resonator mounted on the cathode cavity allows reaching a significant damping of these instabilities, particularly the Helmholtz mode of arc oscillations. The acoustic resonator is coupled with the Helmholtz resonator of the plasma torch limiting the amplitude of arc voltage variations. It is also highlighted that this damping is dependent on friction effects in the acoustic resonator.

  16. Distribution of excited species in plasmas by monochromatic imaging

    SciTech Connect (OSTI)

    Hareland, W.A.; Buss, R.J. [Sandia National Labs., Albuquerque, NM (United States)] [Sandia National Labs., Albuquerque, NM (United States)

    1996-02-01T23:59:59.000Z

    Optical emissions from glow discharges have been measured for more than a century and have yielded much of the data on atomic and molecular spectroscopy. In recent years, measuring the intensity of specific emission lines from processing plasmas has become a routine method for process monitoring and control. Here, spatial maps of individual argon atomic emissions are measured in the GEC (gaseous electronic conference) reference reactor by monochromatic imaging. The plasma discharge is viewed through a grating monochromator, and the images are recorded with an intensified charge-coupled device (CCD) array detector. Each atomic emission has a unique spatial profile that is related to the spatial energy distribution in the plasma.

  17. Study of surface kinetics in PECVD chamber cleaning using remote plasma source

    E-Print Network [OSTI]

    An, Ju Jin

    2008-01-01T23:59:59.000Z

    The scope of this research work is to characterize the Transformer Coupled Toroidal Plasma (TCTP); to understand gas phase reactions and surface reactions of neutrals in the cleaning chamber by analyzing the concentration ...

  18. Three tooth kinematic coupling

    DOE Patents [OSTI]

    Hale, Layton C. (Livermore, CA)

    2000-01-01T23:59:59.000Z

    A three tooth kinematic coupling based on having three theoretical line contacts formed by mating teeth rather than six theoretical point contacts. The geometry requires one coupling half to have curved teeth and the other coupling half to have flat teeth. Each coupling half has a relieved center portion which does not effect the kinematics, but in the limit as the face width approaches zero, three line contacts become six point contacts. As a result of having line contact, a three tooth coupling has greater load capacity and stiffness. The kinematic coupling has application for use in precision fixturing for tools or workpieces, and as a registration device for a work or tool changer or for optics in various products.

  19. Modeling of the coal gasification processes in a hybrid plasma torch

    SciTech Connect (OSTI)

    Matveev, I.B.; Serbin, S.I. [Applied Plasma Technology, Mclean, VA (USA)

    2007-12-15T23:59:59.000Z

    The major advantages of plasma treatment systems are cost effectiveness and technical efficiency. A new efficient electrodeless 1-MW hybrid plasma torch for waste disposal and coal gasification is proposed. This product merges several solutions such as the known inductive-type plasma torch, innovative reverse-vortex (RV) reactor and the recently developed nonequilibrium plasma pilot and plasma chemical reactor. With the use of the computational-fluid-dynamics-computational method, preliminary 3-D calculations of heat exchange in a 1-MW plasma generator operating with direct vortex and RV have been conducted at the air flow rate of 100 g/s. For the investigated mode and designed parameters, reduction of the total wall heat transfer for the reverse scheme is about 65 kW, which corresponds to an increase of the plasma generator efficiency by approximately 6.5%. This new hybrid plasma torch operates as a multimode, high power plasma system with a wide range of plasma feedstock gases and turn down ratio, and offers convenient and simultaneous feeding of several additional reagents into the discharge zone.

  20. Running surface couplings

    E-Print Network [OSTI]

    S. D. Odintsov; A. Wipf

    1995-06-19T23:59:59.000Z

    We discuss the renormalization group improved effective action and running surface couplings in curved spacetime with boundary. Using scalar self-interacting theory as an example, we study the influence of the boundary effects to effective equations of motion in spherical cap and the relevance of surface running couplings to quantum cosmology and symmetry breaking phenomenon. Running surface couplings in the asymptotically free SU(2) gauge theory are found.

  1. Large ELMs Triggered by MHD in JET Advanced Tokamak Plasmas: Impact on Plasmas Profiles, Plasmas Facing Components and Heating Systems

    E-Print Network [OSTI]

    Large ELMs Triggered by MHD in JET Advanced Tokamak Plasmas: Impact on Plasmas Profiles, Plasmas Facing Components and Heating Systems

  2. The design evaluation of inductive power-transformer for personal rapid transit by measuring impedance

    SciTech Connect (OSTI)

    Han, Kyung-Hee [Department of Electrical Engineering, Dongguk University, Seoul 100-715 (Korea, Republic of); Department of Electricity and Signaling, Korea Railroad Research Institute, Uiwang, Kyonggi 437-050 (Korea, Republic of); Lee, Byung-Song [Department of Electricity and Signaling, Korea Railroad Research Institute, Uiwang, Kyonggi 437-050 (Korea, Republic of); Baek, Soo-Hyun [Department of Electrical Engineering, Dongguk University, Seoul 100-715 (Korea, Republic of)

    2008-04-01T23:59:59.000Z

    The contact-less inductive power transformer (IPT) uses the principle of electromagnetic induction. The concept of the IPT for vehicles such as the personal rapid transit (PRT) system is proposed and some suggestions for power collector design of IPT to improve power transfer performance are presented in this paper. The aim of this paper is to recommend the concept of IPT for vehicles such as the PRT system and also to present some propositions for the power collector design of the IPT, which is to improve the power transfer performance. Generally, there are diverse methods to evaluate transfer performance of the traditional transformers. Although the principle of IPT is similar to that of the general transformer, it is impossible to apply the methods directly because of large air gap. The system must be compensated by resonant circuit due to the large air gap. Consequently, it is difficult to apply numerical formulas to the magnetic design of IPT systems. This paper investigates the magnetic design of a PRT system using three-dimensional magnetic modeling and measurements of the pick-up coupling coefficient and its impedances. In addition, how the use of Litz wire and leakage inductance is related will be observed through experiment and simulation.

  3. Two-dimensional double layer in plasma in a diverging magnetic field

    SciTech Connect (OSTI)

    Saha, S. K.; Raychaudhuri, S.; Chowdhury, S.; Janaki, M. S.; Hui, A. K. [Plasma Physics Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)

    2012-09-15T23:59:59.000Z

    Plasma created by an inductive RF discharge is allowed to expand along a diverging magnetic field. Measurement of the axial plasma potential profile reveals the formation of an electric double layer near the throat of the expansion chamber. An accelerated ion beam has been detected in the downstream region, confirming the presence of the double layer. The 2-D nature of the ion energy distribution function of the downstream plasma has been studied by a movable ion energy analyser, which shows that the beam radius increases along the axial distance. The 2-D structure of the plasma potential has been studied by a movable emissive probe. The existence of a secondary lobe in the contour plot of plasma equipotential is a new observation. It is also an interesting observation that the most diverging magnetic field line not intercepting the junction of the discharge tube and the expansion chamber has an electric field aligned with it.

  4. Two-beam high-order harmonics from solids: Coupling mechanisms

    SciTech Connect (OSTI)

    Tarasevitch, A.; Wieczorek, J.; Kohn, R.; Bovensiepen, U.; Linde, D. von der [Fakultaet fuer Physik, Universitaet Duisburg-Essen, Lotharstr. 1, 47048 Duisburg (Germany)

    2010-11-15T23:59:59.000Z

    The polarization of the two beam (driver-probe) high-order harmonic generation from solids is measured. The experiments, together with computer simulations, allow us to distinguish two different coupling mechanisms of the driver and the probe, resulting in different harmonic efficiencies and spectral slopes. We find that in the nonrelativistic regime the coupling is mostly due to the nonlinear plasma density modulation.

  5. System and method for generating steady state confining current for a toroidal plasma fusion reactor

    DOE Patents [OSTI]

    Bers, Abraham (Arlington, MA)

    1981-01-01T23:59:59.000Z

    A system for generating steady state confining current for a toroidal plasma fusion reactor providing steady-state generation of the thermonuclear power. A dense, hot toroidal plasma is initially prepared with a confining magnetic field with toroidal and poloidal components. Continuous wave RF energy is injected into said plasma to estalish a spectrum of traveling waves in the plasma, where the traveling waves have momentum components substantially either all parallel, or all anti-parallel to the confining magnetic field. The injected RF energy is phased to couple to said traveling waves with both a phase velocity component and a wave momentum component in the direction of the plasma traveling wave components. The injected RF energy has a predetermined spectrum selected so that said traveling waves couple to plasma electrons having velocities in a predetermined range .DELTA.. The velocities in the range are substantially greater than the thermal electron velocity of the plasma. In addition, the range is sufficiently broad to produce a raised plateau having width .DELTA. in the plasma electron velocity distribution so that the plateau electrons provide steady-state current to generate a poloidal magnetic field component sufficient for confining the plasma. In steady state operation of the fusion reactor, the fusion power density in the plasma exceeds the power dissipated inthe plasma.

  6. System and method for generating steady state confining current for a toroidal plasma fusion reactor

    DOE Patents [OSTI]

    Fisch, Nathaniel J. (Cambridge, MA)

    1981-01-01T23:59:59.000Z

    A system for generating steady state confining current for a toroidal plasma fusion reactor providing steady-state generation of the thermonuclear power. A dense, hot toroidal plasma is initially prepared with a confining magnetic field with toroidal and poloidal components. Continuous wave RF energy is injected into said plasma to establish a spectrum of traveling waves in the plasma, where the traveling waves have momentum components substantially either all parallel, or all anti-parallel to the confining magnetic field. The injected RF energy is phased to couple to said traveling waves with both a phase velocity component and a wave momentum component in the direction of the plasma traveling wave components. The injected RF energy has a predetermined spectrum selected so that said traveling waves couple to plasma electrons having velocities in a predetermined range .DELTA.. The velocities in the range are substantially greater than the thermal electron velocity of the plasma. In addition, the range is sufficiently broad to produce a raised plateau having width .DELTA. in the plasma electron velocity distribution so that the plateau electrons provide steady-state current to generate a poloidal magnetic field component sufficient for confining the plasma. In steady state operation of the fusion reactor, the fusion power density in the plasma exceeds the power dissipated in the plasma.

  7. Supersonic drift-tearing magnetic islands in tokamak plasmas R. Fitzpatrick, and F.L. Waelbroeck

    E-Print Network [OSTI]

    Fitzpatrick, Richard

    by the plasma. Since the waves carry momentum, the inner region exerts a net force on the outer region, and vice the radial direc- tion) helical magnetic islands.3 Such islands degrade plasma confinement because heat weak coupling to drift-acoustic waves.13­16 On the other hand, supersonic island solutions

  8. Hypersonic drift-tearing magnetic islands in tokamak plasmas R. Fitzpatrick and F. L. Waelbroeck

    E-Print Network [OSTI]

    Fitzpatrick, Richard

    by the plasma. Since the waves carry momentum, the inner region exerts a net force on the intermediate region Such islands degrade plasma confinement because heat and particles are able to travel radially from one side to that of the unperturbed local ion fluid, and a relatively weak coupling to drift- acoustic waves.13­16 On the other hand

  9. Plasma-Therm Workshop: Fundamentals of Plasma Processing (Etching & Deposition)

    E-Print Network [OSTI]

    Martin, Jan M.L.

    The workshop will focus on the fundamentals of plasma etching and deposition. Lectures will includePlasma-Therm Workshop: Fundamentals of Plasma Processing (Etching & Deposition) Nanofabrication an introduction to vacuum technology, the basics of plasma and plasma reactors and an overview of mechanisms

  10. Business Name Year Address City State Zip Phone Email Address Contact

    E-Print Network [OSTI]

    .com Manufacturing/wholesale trade/service/retail 3251 Basic chemical manufacturing Plasma Biofuels 2007 P.O. Box://plasmetc orp.com/ Plasma Biofuels currently uses Induction-Coupled Plasma (ICP) gasifiers with various IP

  11. Universal holographic hydrodynamics at finite coupling

    E-Print Network [OSTI]

    Alex Buchel; Robert C. Myers; Miguel F. Paulos; Aninda Sinha

    2008-09-12T23:59:59.000Z

    We consider thermal plasmas in a large class of superconformal gauge theories described by a holographic dual geometry of the form $AdS_5\\times M_5$. In particular, we demonstrate that all of the thermodynamic properties and hydrodynamic transport parameters for a large class of superconformal gauge theories exhibit a certain universality to leading order in the inverse 't Hooft coupling and $1/N_c$. In particular, we show that independent of the compactification geometry, the leading corrections are derived from the same five-dimensional effective supergravity action supplemented by a term quartic in the five-dimensional Weyl tensor.

  12. Translation-coupling systems

    DOE Patents [OSTI]

    Pfleger, Brian; Mendez-Perez, Daniel

    2013-11-05T23:59:59.000Z

    Disclosed are systems and methods for coupling translation of a target gene to a detectable response gene. A version of the invention includes a translation-coupling cassette. The translation-coupling cassette includes a target gene, a response gene, a response-gene translation control element, and a secondary structure-forming sequence that reversibly forms a secondary structure masking the response-gene translation control element. Masking of the response-gene translation control element inhibits translation of the response gene. Full translation of the target gene results in unfolding of the secondary structure and consequent translation of the response gene. Translation of the target gene is determined by detecting presence of the response-gene protein product. The invention further includes RNA transcripts of the translation-coupling cassettes, vectors comprising the translation-coupling cassettes, hosts comprising the translation-coupling cassettes, methods of using the translation-coupling cassettes, and gene products produced with the translation-coupling cassettes.

  13. Segmented ceramic liner for induction furnaces

    DOE Patents [OSTI]

    Gorin, A.H.; Holcombe, C.E.

    1994-07-26T23:59:59.000Z

    A non-fibrous ceramic liner for induction furnaces is provided by vertically stackable ring-shaped liner segments made of ceramic material in a light-weight cellular form. The liner segments can each be fabricated as a single unit or from a plurality of arcuate segments joined together by an interlocking mechanism. Also, the liner segments can be formed of a single ceramic material or can be constructed of multiple concentric layers with the layers being of different ceramic materials and/or cellular forms. Thermomechanically damaged liner segments are selectively replaceable in the furnace. 5 figs.

  14. Plasma Physics and Controlled Fusion, Vol. 26. No. 4, pp. 589 to 602, 1984 0741-3335r84$3.00 + .OF Printed in Great Britain. @ 1984institute o?Wysics and Pergamon Press Ltd.

    E-Print Network [OSTI]

    Sprott, Julien Clinton

    . INTRODUCTION WAVEheating of magnetically confined plasma has become a major focus of numerous plasma physicsPlasma Physics and Controlled Fusion, Vol. 26. No. 4, pp. 589 to 602, 1984 0741-3335r84$3.00 + .OF is produced (300 and 50 eV) with 500 kW of r.f. power coupled into a 5 x 10" cm-3 plasma. Power is coupled

  15. The model coupling toolkit.

    SciTech Connect (OSTI)

    Larson, J. W.; Jacob, R. L.; Foster, I.; Guo, J.

    2001-04-13T23:59:59.000Z

    The advent of coupled earth system models has raised an important question in parallel computing: What is the most effective method for coupling many parallel models to form a high-performance coupled modeling system? We present our solution to this problem--The Model Coupling Toolkit (MCT). We explain how our effort to construct the Next-Generation Coupler for NCAR Community Climate System Model motivated us to create this toolkit. We describe in detail the conceptual design of the MCT and explain its usage in constructing parallel coupled models. We present preliminary performance results for the toolkit's parallel data transfer facilities. Finally, we outline an agenda for future development of the MCT.

  16. Inductive Inference for Solving Divergence in Knuth-Bendix Completion

    E-Print Network [OSTI]

    Thomas, M.; Jantke, K.; Proceedings of Analogical and Inductive Inference '89, Lecture Notes in Computer Science, Volume 397 pp 288-303 Springer [More Details

    Thomas,M. Jantke,K. Proceedings of Analogical and Inductive Inference '89, Lecture Notes in Computer Science, Volume 397 pp 288-303 Springer

  17. ac induction motors: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    242 EA Systems Examples Induction and Recursion Length Measuring the Universe Analysis Number systems of different lengths, Mathematics Websites Summary: of different lengths, and...

  18. Cold Crucible Induction Melter Studies for Making Glass Ceramic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    performed in a pilot-scale (14 scale) cold crucible induction meter (CCIM). Melt viscosity, electrical conductivity, and crystallization behavior upon cooling were measured on...

  19. Novel Manufacturing Technologies for High Power Induction and...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High Power Induction and Permanent Magnet Electric Motors 2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation...

  20. Seismic baseline and induction studies- Roosevelt Hot Springs...

    Open Energy Info (EERE)

    Idaho Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Seismic baseline and induction studies- Roosevelt Hot Springs, Utah and Raft River, Idaho...

  1. A generalized approach to planar induction heating magnetics

    E-Print Network [OSTI]

    Zhang, Richard Yi

    2012-01-01T23:59:59.000Z

    This thesis describes an efficient numerical simulation technique of magnetoquasistatic electromagnetic fields for planar induction heating applications. The technique is based on a volume-element discretization, integral ...

  2. Understanding the Inductances We have identified six different inductances (or reactances) for

    E-Print Network [OSTI]

    McCalley, James D.

    ) Once we obtain Ld and Lq, together with the rotor winding self inductances LF, LD, LG, and LQ the "phase a" stator current for a three-phase fault occurring at the machine terminals. This picture, drawn neglecting the stator transients (since they are very fast), is given below: #12;2 Subtransient period

  3. Aryl hydrocarbon hydroxylase: induction and inhibition

    E-Print Network [OSTI]

    Andres, Janet Lee

    1982-01-01T23:59:59.000Z

    , and toxic potency of halogenated biphenyls. The usefulness of zerovalent nickel catalysis of aryl-aryl coupling in the synthesis of trifluoromethyl-substituted biphenyls was investigated. Although yields were low, this method proved to be effective... as probes for structure-activity studies. However, these compounds are difficult to synthesize by traditional methods. Their synthesis by zerovalent nickel catalytic coupling, as first described by Semmelhack et al. (1971) and modified by Kende et al...

  4. Michigan Institute for Plasma Sci-

    E-Print Network [OSTI]

    Shyy, Wei

    This talk will focus on the achievements of the Drexel Plasma Institute in direct application of plasmasMichigan Institute for Plasma Sci- ence and Engi- neering Seminar Plasma Medicine: Mechanisms of Direct Non-Thermal Plasma Interaction with Living Tissue Prof. Alexander Fridman Drexel University

  5. PLASMA PHYSICS PPPL UC Davis

    E-Print Network [OSTI]

    PRINCETON PLASMA PHYSICS LABORATORY PPPL UC Davis PRINCETON PLASMA PHYSICS LABORATORY PPPL UC Davis. Domier and N.C. Luhmann, Jr. UC at Davis at Workshop on Long Time Simulations of Kinetic Plasmas April 21, 2006 Hyatt Regency, Dallas, TX #12;PRINCETON PLASMA PHYSICS LABORATORY PPPL UC Davis PRINCETON PLASMA

  6. Princeton Plasma Physics Laboratory

    SciTech Connect (OSTI)

    Not Available

    1990-01-01T23:59:59.000Z

    This report discusses the following topics: principal parameters achieved in experimental devices fiscal year 1990; tokamak fusion test reactor; compact ignition tokamak; Princeton beta experiment- modification; current drive experiment-upgrade; international collaboration; x-ray laser studies; spacecraft glow experiment; plasma processing: deposition and etching of thin films; theoretical studies; tokamak modeling; international thermonuclear experimental reactor; engineering department; project planning and safety office; quality assurance and reliability; technology transfer; administrative operations; PPPL patent invention disclosures for fiscal year 1990; graduate education; plasma physics; graduate education: plasma science and technology; science education program; and Princeton Plasma Physics Laboratory reports fiscal year 1990.

  7. BNL | ATF Plasma Diagnostics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    diagnostic enables measurement of plasma wakefields on the picosecond timescale using ultrafast optical probe pulses. Although in this frequency domain interferometry has yet...

  8. Global model of a gridded-ion thruster powered by a radiofrequency inductive coil

    SciTech Connect (OSTI)

    Chabert, P.; Arancibia Monreal, J.; Bredin, J.; Popelier, L.; Aanesland, A. [LPP, CNRS, Ecole Polytechnique, UPMC, Paris XI, 91128 Palaiseau (France)

    2012-07-15T23:59:59.000Z

    A global (volume-averaged) model of a gridded-ion thruster is proposed. The neutral propellant (xenon gas) is injected into the thruster chamber at a fixed rate and a plasma is generated by circulating a radiofrequency current in an inductive coil. The ions generated in this plasma are accelerated out of the thruster by a pair of DC biased grids. The neutralization downstream is not treated. Xenon atoms also flow out of the thruster across the grids. The model, based on particle and energy balance equations, solves for four global variables in the thruster chamber: the plasma density, the electron temperature, the neutral gas (atom) density, and the neutral gas temperature. The important quantities to evaluate the thruster efficiency and performances are calculated from these variables and from the voltage across the grids. It is found that the mass utilization efficiency rapidly decreases with the gas flow rate. However, the radiofrequency power transfer efficiency increases significantly with the injected gas flow rate. Therefore, there is a compromise to be found between these two quantities.

  9. Non-Equilibrium Vibrational Kinetics in Radiofrequency H2 Plasmas: a Comparison Between Theoretical and Experimental Results

    SciTech Connect (OSTI)

    Capitelli, M. [Department of Chemistry-University of Bari (Italy); IMIP CNR - Bari (Italy); De Pascale, O. [IMIP CNR - Bari (Italy); Shakatov, V. [Centro Laser s.r.l. - Valenzano (Italy); Hassouni, K.; Lombardi, G.; Gicquel, A. [LIMHP-CNRS Universite Paris Nord - Villetaneuse (France)

    2005-05-16T23:59:59.000Z

    Vibrational and rotational experimental temperatures of molecular hydrogen obtained by Coherent Anti-Stokes Spectroscopy (CARS) in Radiofrequency Inductive Plasmas have been analyzed and interpreted in terms of vibration, electron, dissociation-recombination and attachment kinetics. The analysis clarifies the role of atomic hydrogen and its heterogeneous recombination in affecting the vibrational content of the molecules.

  10. TEST OF THE PERFORMANCE AND CHARACTERISTICS OF A PROTOTYPE INDUCTIVE POWER COUPLING FOR ELECTRIC HIGHWAY SYSTEMS

    E-Print Network [OSTI]

    Bolger, J.G.

    2010-01-01T23:59:59.000Z

    operation of an electric vehicle's power system. The 1.30power source Figure 1. Roadway-powered system for electric vehicles.

  11. TEST OF THE PERFORMANCE AND CHARACTERISTICS OF A PROTOTYPE INDUCTIVE POWER COUPLING FOR ELECTRIC HIGHWAY SYSTEMS

    E-Print Network [OSTI]

    Bolger, J.G.

    2010-01-01T23:59:59.000Z

    power Pi - input power Ps - loop conductor power loss Pc -loop capacitor power loss Pf - pickupand source core power loss Pr - pickup capacitor power loss

  12. Modal S-matrix method for the optimum design of inductively direct-coupled

    E-Print Network [OSTI]

    Bornemann, Jens

    . Arndt, Dr.-Ing., Sen.Mem.I.E.E.E., J. Bornemann, Dr.-Ing., D. Heckmann, Dipl.-lng., C. Piontek, Dipl.-lng., H. Semmerow, Dipl.-lng., and H. Schueler, Dipl.-lng. Indexing terms: Computer-aided design

  13. TEST OF THE PERFORMANCE AND CHARACTERISTICS OF A PROTOTYPE INDUCTIVE POWER COUPLING FOR ELECTRIC HIGHWAY SYSTEMS

    E-Print Network [OSTI]

    Bolger, J.G.

    2010-01-01T23:59:59.000Z

    Pickup short circuit current Effective core loss currentPickup short circuit voltage, volts I - Input current, amps

  14. TEST OF THE PERFORMANCE AND CHARACTERISTICS OF A PROTOTYPE INDUCTIVE POWER COUPLING FOR ELECTRIC HIGHWAY SYSTEMS

    E-Print Network [OSTI]

    Bolger, J.G.

    2010-01-01T23:59:59.000Z

    V min. Trojan J 217 lead acid batteries, 14 84 max. Bridgea lead-acid battery pack consisting of 12, 6-V batteries in

  15. Diamond and Related Materials, 2 (1993) 661 666 661 Degenerate four-wave mixing diagnostics of atmospheric pressure

    E-Print Network [OSTI]

    Zare, Richard N.

    -3]. An r.f. inductively coupled plasma offers the benefits of an "electrodeless" discharge for minimum film application of this new spectroscopic technique to an atmospheric pressure plasma synthesis reactor. DFWM measurements of the CH radicals in the boundary layer of an r.f. inductively coupled plasma deposition reactor

  16. Measuring the plasma density of a ferroelectric plasma source in an expanding plasma

    E-Print Network [OSTI]

    Measuring the plasma density of a ferroelectric plasma source in an expanding plasma A. Dunaevsky and N. J. Fisch Princeton Plasma Physics Laboratory, Princeton University, P.O. Box 451, Princeton, New temperature at the surface of a ferroelectric plasma source were deduced from floating probe measurements

  17. High-Energy Plasma Fusion

    E-Print Network [OSTI]

    Guruangan, Karthik

    2014-01-01T23:59:59.000Z

    Simulations of Dense Plasma Focus Z-Pinch Devices.pdfSimulations of Dense-Plasma Focus Z-Pinch Device. Physicalplasmas and dense-plasma focus (DPF) Z-Pinch devices. DPF

  18. Method and apparatus for the formation of a spheromak plasma

    DOE Patents [OSTI]

    Jardin, Stephen C. (Princeton, NJ); Yamada, Masaaki (Lawrenceville, NJ); Furth, Harold P. (Princeton, NJ); Okabayashi, Mitcheo (Princeton, NJ)

    1984-01-01T23:59:59.000Z

    An inductive method and apparatus for forming detached spheromak plasma using a thin-walled metal toroidal ring, with external current leads and internal poloidal and toroidal field coils located inside a vacuum chamber filled with low density hydrogen gas and an external axial field generating coil. The presence of a current in the poloidal field coils, and an externally generated axial field sets up the initial poloidal field configuration in which the field is strongest toward the major axis of the toroid. The internal toroidal-field-generating coil is then pulsed on, ionizing the gas and inducing poloidal current and toroidal magnetic field into the plasma region in the sleeve exterior to and adjacent to the ring and causing the plasma to expand away from the ring and toward the major axis. Next the current in the poloidal field coils in the ring is reversed. This induces toroidal current into the plasma and causes the poloidal magnetic field lines to reconnect. The reconnection continues until substantially all of the plasma is formed in a separated spheromak configuration held in equilibrium by the initial external field.

  19. Effect of Inert Gas Additive Species on Cl(2) High Density Plasma Etching of Compound Semiconductors: Part II. InP, InSb, InGaP and InGaAs

    SciTech Connect (OSTI)

    Abernathy, C.R.; Cho, H.; Hahn, Y.B.; Hays, D.C.; Jung, K.B.; Pearton, S.J.; Shul, R.J.

    1998-12-17T23:59:59.000Z

    The effects of the additive noble gases He, Ar and Xe on chlorine-based Inductively Coupled Plasma etching of InP, InSb, InGaP and InGaAs were studied as a function of source power, chuck power and discharge composition. The etch rates of all materials with C12/He and C12/Xe are greater than with C12/Ar. Etch rates in excess of 4.8 pndmin for InP and InSb with C12/He or C12/Xe, 0.9 pndmin for InGaP with C12/Xe, and 3.8 prdmin for InGaAs with Clz/Xe were obtained at 750 W ICP power, 250 W rf power, - 1570 C12 and 5 mTorr. All three plasma chemistries produced smooth morphologies for the etched InGaP surfaces, while the etched surface of InP showed rough morphology under all conditions.

  20. Fundamentals of Plasma Physics

    E-Print Network [OSTI]

    Callen, James D.

    of students (from physics, engineering physics, elec- trical engineering, nuclear engineering and other un;PREFACE Plasma physics is a relatively new branch of physics that became a mature science over the last). Thus, plasma physics has developed in large part as a branch of applied or engineering physics

  1. Plasma technology directory

    SciTech Connect (OSTI)

    Ward, P.P.; Dybwad, G.L.

    1995-03-01T23:59:59.000Z

    The Plasma Technology Directory has two main goals: (1) promote, coordinate, and share plasma technology experience and equipment within the Department of Energy; and (2) facilitate technology transfer to the commercial sector where appropriate. Personnel are averaged first by Laboratory and next by technology area. The technology areas are accelerators, cleaning and etching deposition, diagnostics, and modeling.

  2. Diamagnetism of rotating plasma

    SciTech Connect (OSTI)

    Young, W. C.; Hassam, A. B.; Romero-Talamas, C. A.; Ellis, R. F.; Teodorescu, C. [IREAP, University of Maryland, College Park, Maryland 20742 (United States)

    2011-11-15T23:59:59.000Z

    Diamagnetism and magnetic measurements of a supersonically rotating plasma in a shaped magnetic field demonstrate confinement of plasma pressure along the magnetic field resulting from centrifugal force. The Grad-Shafranov equation of ideal magnetohydrodynamic force balance, including supersonic rotation, is solved to confirm that the predicted angular velocity is in agreement with spectroscopic measurements of the Doppler shifts.

  3. Coupling in the Tevatron

    SciTech Connect (OSTI)

    Gelfand, N.M.

    1994-12-01T23:59:59.000Z

    The performance of the Fermilab Tevatron Collider at the commencement of run Ib was far below expectations. After a frustrating period of several months, a low-{beta} quad downstream of the interaction point at B0 was found to be rolled. This rolled quadrupole coupled the horizontal and vertical motion of the Tevatron beams. It also made matching the beam from the Main Ring to the Tevatron impossible, resulting in emittance blow up on injection. The net result of the roll was a significant reduction in the Tevatron luminosity. When the roll in the quadrupole was corrected the performance of the Tevatron improved dramatically. This note will discuss the experimental data indicating the presence of coupling and subsequent calculations which show how coupling an affect the luminosity. It is not intended to exhaust a discussion of coupling, which hopefully will be understood well enough to be discussed in a subsequent note.

  4. Negative-coupling resonances in pump-coupled lasers

    E-Print Network [OSTI]

    T. W. Carr; M. L. Taylor; I. B. Schwartz

    2005-10-28T23:59:59.000Z

    We consider coupled lasers, where the intensity deviations from the steady state, modulate the pump of the other lasers. Most of our results are for two lasers where the coupling constants are of opposite sign. This leads to a Hopf bifurcation to periodic output for weak coupling. As the magnitude of the coupling constants is increased (negatively) we observe novel amplitude effects such as a weak coupling resonance peak and, strong coupling subharmonic resonances and chaos. In the weak coupling regime the output is predicted by a set of slow evolution amplitude equations. Pulsating solutions in the strong coupling limit are described by discrete map derived from the original model.

  5. Computational analysis of temperature rise phenomena in electric induction motors

    E-Print Network [OSTI]

    Melnik, Roderick

    machines in general, and induction motors in particular, temperature limits is a key factor affectingComputational analysis of temperature rise phenomena in electric induction motors Ying Huai Kraftwerkstechnik, PetersenstraÃ?e 30, 64287 Darmstadt, Germany b Faculty of Science and Engineering, Mads Clausen

  6. Modelling Inhibition in Metabolic Pathways Through Abduction and Induction

    E-Print Network [OSTI]

    Pazos, Florencio

    Modelling Inhibition in Metabolic Pathways Through Abduction and Induction Alireza Tamaddoni abduction and induction can be used to understand the functional class of unknown enzymes or inhibitors. We show how we can model, within Abductive Logic Programming (ALP), inhibition in metabolic pathways

  7. Brazdil, P. and Gama, J., 1998 Constructive Induction

    E-Print Network [OSTI]

    Morik, Katharina

    1 Brazdil, P. and Gama, J., 1998 Constructive Induction on Continuous Spaces In Liu, H./Motada, H.: Feature Extraction Construction and Selection, A Data Mining Perspective. Chapter 18, pages S.289. ,,oblique") Probleme. + at2 at1 - H #12;11 Constructive Induction: "the application of a set of constructive

  8. Stator current demodulation for induction machine rotor faults diagnosis

    E-Print Network [OSTI]

    Boyer, Edmond

    with emphasis on stator current processing [1], [2]. It has been proven that mechanical and electrical faultsStator current demodulation for induction machine rotor faults diagnosis El Houssin El Bouchikhi of the stator currents. Hence, demodulation of the stator currents is of high interest for induction machines

  9. Induction, Domains, Calculi: Strachey's Contributions to ProgrammingLanguage

    E-Print Network [OSTI]

    Schmidt, David A.

    Induction, Domains, Calculi: Strachey's Contributions to Programming­Language Engineering David A's contributions---inductive defini­ tion of semantics, semantic­domain definitions, and calculi for semantic description---are presented, and their consequences on languages research are described. Strachey's impact

  10. Improved Unsupervised POS Induction through Prototype Discovery Omri Abend1

    E-Print Network [OSTI]

    Rappoport, Ari

    Rappoport1 1 Institute of Computer Science, 2 ICNC Hebrew University of Jerusalem {omria01|roiri|arir}@cs.huji.ac.il Abstract We present a novel fully unsupervised al- gorithm for POS induction from plain text, motivated and for multi-lingual systems (Jiang et al., 2009). Automatic induction of POS tags from plain text can greatly

  11. Plasma opening switch

    DOE Patents [OSTI]

    Savage, Mark E. (Albuquerque, NM); Mendel, Jr., Clifford W. (Albuquerque, NM)

    2001-01-01T23:59:59.000Z

    A command triggered plasma opening switch assembly using an amplification stage. The assembly surrounds a coaxial transmission line and has a main plasma opening switch (POS) close to the load and a trigger POS upstream from the main POS. The trigger POS establishes two different current pathways through the assembly depended on whether it has received a trigger current pulse. The initial pathway has both POS's with plasma between their anodes and cathodes to form a short across the transmission line and isolating the load. The final current pathway is formed when the trigger POS receives a trigger current pulse which energizes its fast coil to push the conductive plasma out from between its anode and cathode, allowing the main transmission line current to pass to the fast coil of the main POS, thus pushing its plasma out the way so as to establish a direct current pathway to the load.

  12. Coupled Monte Carlo neutral uid plasma simulation of Alcator C-Mod divertor plasma near detachment

    E-Print Network [OSTI]

    Karney, Charles

    . � 1999 Elsevier Science B.V. All rights reserved. Keywords: B2/EIRENE; Alcator C-Mod; Pressure-balance as it exhibits at Journal of Nuclear Materials 266±269 (1999) 947±952 * Corresponding author. Tel.: +1 609 243, Albuquerque, NM, USA. 0022-3115/99/$ ± see front matter � 1999 Elsevier Science B.V. All rights reserved. PII

  13. Induction accelerators for the phase rotator system

    SciTech Connect (OSTI)

    Reginato, Lou; Yu, Simon; Vanecek, Dave

    2001-07-30T23:59:59.000Z

    The principle of magnetic induction has been applied to the acceleration of high current beams in betatrons and a variety of induction accelerators. The linear induction accelerator (LIA) consists of a simple nonresonant structure where the drive voltage is applied to an axially symmetric gap that encloses a toroidal ferromagnetic material. The change in flux in the magnetic core induces an axial electric field that provides particle acceleration. This simple nonresonant (low Q) structure acts as a single turn transformer that can accelerate from hundreds of amperes to tens of kiloamperes, basically only limited by the drive impedance. The LIA is typically a low gradient structure that can provide acceleration fields of varying shapes and time durations from tens of nanoseconds to several microseconds. The efficiency of the LIA depends on the beam current and can exceed 50% if the beam current exceeds the magnetization current required by the ferromagnetic material. The acceleration voltage available is simply given by the expression V=A dB/dt. Hence, for a given cross section of material, the beam pulse duration influences the energy gain. Furthermore, a premium is put on minimizing the diameter, which impacts the total weight or cost of the magnetic material. The diameter doubly impacts the cost of the LIA since the power (cost) to drive the cores is proportional to the volume as well. The waveform requirements during the beam pulse makes it necessary to make provisions in the pulsing system to maintain the desired dB/dt during the useful part of the acceleration cycle. This is typically done two ways, by using the final stage of the pulse forming network (PFN) and by the pulse compensation network usually in close proximity of the acceleration cell. The choice of magnetic materials will be made by testing various materials both ferromagnetic and ferrimagnetic. These materials will include the nickel-iron, silicon steel amorphous and various types of ferrites not only to determine the properties that are essential in this application but the energy losses in the magnetization process which directly impact the cost.

  14. aqueous wastes wet: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    from nuclear waste materials using inductively coupled plasma-atomic emission spectrometry CERN Preprints Summary: 1.1 This practice is applicable to the determination of low...

  15. U.S. Department of Energy Categorical Exclusion ...

    Broader source: Energy.gov (indexed) [DOE]

    Analytical Development Leeman Prodigy and Perkin Elmer Optima 3000 Inductively Coupled Plasma Emission Spectrometers (ICPES) perform elemental analysis on liquid samples. B3.6 -...

  16. U.S. Department of Energy Categorical Exclusion ...

    Broader source: Energy.gov (indexed) [DOE]

    Operation and Maintenance of Inductively Coupled Plasma Mass Spectrometry Method in 773, B142 Savannah River Site AikenAikenSouth Carolina The Analytical Development Section will...

  17. atomic spectrometry update: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    from nuclear waste materials using inductively coupled plasma-atomic emission spectrometry CERN Preprints Summary: 1.1 This practice is applicable to the determination of low...

  18. auxiliary heated regimes: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    coupled, and is characteristic skin depth of the wave) and may be observed in low pressure inductive plasmas driven at low. The resonant absorption of the electromagnetic...

  19. Relationship between microstructures and grain-scale trace element distribution in komatiite-hosted magmatic sulphide ores

    E-Print Network [OSTI]

    2013 Available online 6 November 2013 Keywords: Komatiite hosted Ni sulphides EBSD Laser ablation ICP) have been studied by electron backscatter diffraction and laser ablation inductively coupled plasma

  20. Apatite in early Archean Isua supracrustal rocks, southern West Greenland: its origin, association with graphite and

    E-Print Network [OSTI]

    Arrhenius, Gustaf

    ), metacherts, metacarbonates and mafic dykes in the Isua supracrustal belt (ISB) have been determined by laser ablation inductively coupled plasma mass spectrometry. The results together with petrographic observations