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Sample records for ecr plasma device

  1. A new numerical description of the interaction of an ion beam with a magnetized plasma in an ECR-based charge breeding device

    Science.gov (United States)

    Galatà, A.; Mascali, D.; Neri, L.; Celona, L.

    2016-08-01

    The ion beam-plasma interaction is a relevant topic in several fields of plasma physics, from fusion devices to modern ion sources. This paper discusses the numerical modelling of the whole beam-plus-plasma-target system in case of 1+  ions entering an ECR-based charge breeder (ECR-CB). The model is able to reproduce the ion capture and the creation of the first charge states in the selected physics case, i.e. the interaction of a 85Rb1+ ions with the plasma of the 14.5 GHz PHOENIX ECR-CB installed at the Laboratoire de Physique Subatomique et de Cosmologie (LPSC) of Grenoble. The results show that a very narrow window of physical parameters for both the beam (energy and energy spread especially) and plasma (ion temperature, density, density structural distribution, self-generated ambipolar fields) exists which is able to reproduce very well the experimental results, providing an exhaustive picture of the involved phenomena. Possible non-linear interactions and the role played by the eventual onset of instabilities are also discussed.

  2. Characteristics of Surface Sterilization using ECR Plasma

    Science.gov (United States)

    Yonesu, Akira; Hara, Kazufumi; Nishikawa, Tatsuya; Hayashi, Nobuya

    2015-09-01

    Plasma sterilization techniques have superior characteristics such as a short treatment times, non-toxicity and low thermal damages on the sterilized materials. In plasma sterilization, microorganisms can be sterilized by active radicals, energetic charged particles, and vacuum UV radiation. The influence of each factor depends on the plasma operating parameters. Microwave discharges under the electron cyclotron resonance (ECR) condition produce higher electron temperature and density plasma as compared with other plasma generation techniques. In the present study, characteristics of surface sterilization using ECR plasma have been investigated.The experiment was performed in the vacuum chamber which contains a magnet holder. A pair of rectangular Sm-Co permanent magnets is aligned parallel to each other within the magnet holder. The region of the magnetic field for ECR exists near the magnet holder surface. When the microwave is introduced into the vacuum chamber, a ECR plasma is produced around surface of the magnet holder. High energy electrons and oxygen radicals were observed at ECR zone by electric probe method and optical spectroscopic method. Biological indicators (B.I.) having spore of 106 was sterilized in 2min for oxygen discharge. The temperature of the B.I. installation position was about 55°. The sterilization was achieved by the effect of oxygen radicals and high energy electrons.

  3. Hydrogen Recovery by ECR Plasma Pyrolysis of Methane Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Development of a microgravity and hypogravity compatible Electron Cyclotron Resonance (ECR) Plasma Methane Pyrolysis Reactor is proposed to recover hydrogen which is...

  4. ECR plasma cleaning for superconducting cavities

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Suehiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2000-02-01

    A superconducting linac has been operating well as a heavy ion energy booster of the tandem accelerator at JAERI since 1994. Forty superconducting quarter wave resonators are used in the linac. They have high performances in average. Some of them are, however, suffering from 'Q-disease' that has been caused by hydrogen absorption into niobium during electro-polishing and the precipitation of niobium-hydrides on the surface at the vicinity of about 120K during precooling. A method of electron cyclotron resonance (ECR) plasma cleaning was applied to spare resonator in order to investigate if it is useful as a curing method of Q-disease. ECR plasma was excited in the resonator by 2.45 GHz microwave in a magnetic field of about 87.5 mT. In the first preliminary experiments, hydrogen, helium, water and oxigen gases were investigated. Every case was done at a pressure of about 3x10{sup -3} Pa. The results show that apparent recovery from Q-disease was found with helium and oxigen gases. (author)

  5. Plasma heating due to X-B mode conversion in a cylindrical ECR plasma system

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, V.K.; Bora, D. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat (India)

    2004-07-01

    Extra Ordinary (X) mode conversion to Bernstein wave near Upper Hybrid Resonance (UHR) layer plays an important role in plasma heating through cyclotron resonance. Wave generation at UHR and parametric decay at high power has been observed during Electron Cyclotron Resonance (ECR) heating experiments in toroidal magnetic fusion devices. A small linear system with ECR and UHR layer within the system has been used to conduct experiments on X-B conversion and parametric decay process as a function of system parameters. Direct probing in situ is conducted and plasma heating is evidenced by soft x-ray emission measurement. Experiments are performed with hydrogen plasma produced with 160-800 W microwave power at 2.45 GHz of operating frequency at 10{sup -3} mbar pressure. The axial magnetic field required for ECR is such that the resonant surface (B = 875 G) is situated at the geometrical axis of the plasma system. Experimental results will be presented in the paper. (authors)

  6. Angular distributions of bremsstrahlung photons from ECR plasma

    Science.gov (United States)

    Kumwenda, M. J.; Ahn, J. K.; Lee, J. W.; Lugendo, I. J.; Kim, S. J.; Park, J. Y.; Won, M. S.

    2017-12-01

    High-energy bremsstrahlung photon emission beyond a critical energy from electron cyclotron resonance (ECR) heating has long attracted much attention, and its nature has yet been unsolved. We have measured bremsstrahlung photons from the 28-GHz ECR ion source at Busan Center of Korean Basic Science Institute. The gamma-ray detection system consists of three NaI(Tl) scintillation detectors placed 62 cm radially from the beam axis and a NaI(Tl) scintillation detector at the extraction port for monitoring the photon intensity along the beam axis. Bremsstrahlung photon energy spectra were measured at nine azimuthal angles at the RF power of 1 kW. Azimuthal angular distributions of bremsstrahlung photons were found to be in coincidence with the structure the ECR ion source and the shape of ECR plasma.

  7. Harmonics generation near ion-cyclotron frequency of ECR plasma

    Science.gov (United States)

    Chowdhury, Satyajit; Biswas, Subir; Chakrabarti, Nikhil; Pal, Rabindranath

    2017-10-01

    Wave excitation at different frequency regime is employed in the MaPLE device ECR plasma for varied excitation amplitude. At very low amplitude excitation, mainly fundamental frequency mode of the exciter signal frequency comes into play. With the increase in amplitude of applied perturbation, harmonics are generated and dominant over the fundamental frequency mode. There is a fixed critical amplitude of exciter to yield the harmonics and is independent of applied frequency. Observed harmonics and the main frequency mode has propagation characteristics and are discussed here. Exact mode number and propagation nature are also tried to measure in the experiment. Detailed experimental results will be presented. Department of Science and Technology of Government of India (Project No. SB/S2/HEP-005/2014).

  8. Modification of sensing properties of metallophthalocyanine by an ECR plasma

    Energy Technology Data Exchange (ETDEWEB)

    Naddaf, M.; Chakane, S.; Jain, S.; Bhoraskar, S.V. E-mail: svb@physics.unipune.ernet.in; Mandale, A.B

    2002-07-01

    Lead Phthalocyanine (PC) tetracarboxylic acid prepared by chemical reaction from phthalic anhydride and urea was used as sensor element for sensing humidity and alcohol vapors. The surface was treated with electron cyclotron resonance (ECR) plasma consisting of 25% H{sub 2} and 75% N{sub 2}. Remarkable improvement in the selectivity with respect to ethyl alcohol and reduction in the sensitivity for humidity was observed after this treatment. The response and recovery time for resistive sensing were of the order of 50 and 30 s respectively. X-ray photoelectron spectroscopy and Fourier transformation infra red studies showed that the increased cross-linking of PC is responsible for the creation of new functional groups which have imparted the sensing of alcohol vapor through extrinsic doping.

  9. Proceedings of the 10th international workshop on ECR ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, F W; Kirkpatrick, M I [eds.

    1991-01-01

    This report contains papers on the following topics: Recent Developments and Future Projects on ECR Ion Sources; Operation of the New KVI ECR Ion Source at 10 GHz; Operational Experience and Status of the INS SF-ECR Ion Source; Results of the New ECR4'' 14.5 GHz ECRIS; Preliminary Performance of the AECR; Experimental Study of the Parallel and Perpendicular Particle Losses from an ECRIS Plasma; Plasma Instability in Electron Cyclotron Resonance Heated Ion Sources; The Hyperbolic Energy Analyzer; Status of ECR Source Development; The New 10 GHz CAPRICE Source; First Operation of the Texas A M ECR Ion Source; Recent Developments of the RIKEN ECR Ion Sources; The 14 GHz CAPRICE Source; Characteristics and Potential Applications of an ORNL Microwave ECR Multicusp Plasma Ion Source; ECRIPAC: The Production and Acceleration of Multiply Charged Ions Using an ECR Plasma; ECR Source for the HHIRF Tandem Accelerator; Feasibility Studies for an ECR-Generated Plasma Stripper; Production of Ion Beams by using the ECR Plasmas Cathode; A Single Stage ECR Source for Efficient Production of Radioactive Ion Beams; The Single Staged ECR Source at the TRIUMF Isotope Separator TISOL; The Continuous Wave, Optically Pumped H{sup {minus}} Source; The H{sup +} ECR Source for the LAMPF Optically Pumped Polarized Ion Source; Present Status of the Warsaw CUSP ECR Ion Source; An ECR Source for Negative Ion Production; GYRAC-D: A Device for a 200 keV ECR Plasma Production and Accumulation; Status Report of the 14.4 GHZ ECR in Legnaro; Status of JYFL-ECRIS; Report on the Uppsala ECRIS Facility and Its Planned Use for Atomic Physics; A 10 GHz ECR Ion Source for Ion-Electron and Ion-Atom Collision Studies; and Status of the ORNL ECR Source Facility for Multicharged Ion Collision Research.

  10. Mean energy of ions at outlet of a type Ecr plasma source; Energia promedio de los iones a la salida de una fuente de plasma tipo ECR

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez T, C.; Gonzalez D, J. [Departamento de Fisica, ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1998-07-01

    In this work it is described the calculations to mean energy of the ions in the extraction zone of a type Ecr plasma source considering the presence of a metallic substrate. This zone is characterized by the existence of a divergent magnetic field. It is showed that mean energy is function as the distance between the outlet and substrate as the value of the external magnetic field. (Author)

  11. Enhancement of Field Emission Properties of Carbon Nanotubes by ECR-Plasma Treatment

    Directory of Open Access Journals (Sweden)

    Javid Ali

    2014-01-01

    Full Text Available We report a significant improvement in electron field emission property of carbon nanotubes film by using an electron cyclotron resonance plasma treatment. Our research results reveal that plasma treatment can modify the surface morphology and enhance the field emission characteristics of carbon nanotubes. Raman spectra indicate that plasma treated CNTs sample has lesser defects. Before plasma treatment, low current density of 6.5 mA/cm2 at 3.0 V/μm and at a high turn-on field Eto of 2.4 V/μm was observed. ECR plasma treated CNTs showed a high current density of 20.0 mA/cm2 at 3.0 V/μm and at a low Eto of 1.6 V/μm. The calculated enhancement factors are 694 and 8721 for ECR-plasma untreated and treated carbon nanotubes, respectively. We found an increase in the enhancement factor and emission current after the ECR-plasma treatment. This may be attributed to creation of geometrical features through the removal of amorphous carbon and catalyst particles.

  12. Radioactive ion beams of 111In using ECR plasma sputtering method

    Science.gov (United States)

    Naik, Vaishali; Bhattacharjee, Mahuwa; Kumar, D. Lavanya; Karmakar, Prasanta; Das, S. K.; Banerjee, Debashis; Chattopadhyay, Sankha; Barua, Luna; Das, Sujata Saha; Pal, Asit Kumar; Bandyopadhyay, Arup; Chakrabarti, Alok

    2017-06-01

    Radioactive ion beams of 111In (indium-111, half-life 2.8 days) have been produced using the plasma sputtering method in an electron cyclotron resonance (ECR) ion source at the Variable Energy Cyclotron Centre RIB facility. Indium isotopes were first produced by bombarding a natural silver target with a 32 MeV, 40 μ A alpha particle beam from the K-130 cyclotron. After radio-chemical separation, about 25 mCi In-chloride was deposited on an aluminum electrode and inserted in the plasma chamber of the ECR. Indium ions produced by ion induced sputtering in the plasma were extracted from the ion source, isotopically separated, and a pure 111In beam was measured at the focal plane of the separator. The measured 111In beam intensity was 2.67 × 105 particles/s for a beam energy of 5 keV.

  13. Very Large Area/Volume Microwave ECR Plasma and Ion Source

    Science.gov (United States)

    Foster, John E. (Inventor); Patterson, Michael J. (Inventor)

    2009-01-01

    The present invention is an apparatus and method for producing very large area and large volume plasmas. The invention utilizes electron cyclotron resonances in conjunction with permanent magnets to produce dense, uniform plasmas for long life ion thruster applications or for plasma processing applications such as etching, deposition, ion milling and ion implantation. The large area source is at least five times larger than the 12-inch wafers being processed to date. Its rectangular shape makes it easier to accommodate to materials processing than sources that are circular in shape. The source itself represents the largest ECR ion source built to date. It is electrodeless and does not utilize electromagnets to generate the ECR magnetic circuit, nor does it make use of windows.

  14. X-ray pinhole camera setups used in the Atomki ECR Laboratory for plasma diagnostics

    Science.gov (United States)

    Rácz, R.; Biri, S.; Pálinkás, J.; Mascali, D.; Castro, G.; Caliri, C.; Romano, F. P.; Gammino, S.

    2016-02-01

    Imaging of the electron cyclotron resonance (ECR) plasmas by using CCD camera in combination with a pinhole is a non-destructive diagnostics method to record the strongly inhomogeneous spatial density distribution of the X-ray emitted by the plasma and by the chamber walls. This method can provide information on the location of the collisions between warm electrons and multiple charged ions/atoms, opening the possibility to investigate the direct effect of the ion source tuning parameters to the plasma structure. The first successful experiment with a pinhole X-ray camera was carried out in the Atomki ECR Laboratory more than 10 years ago. The goal of that experiment was to make the first ECR X-ray photos and to carry out simple studies on the effect of some setting parameters (magnetic field, extraction, disc voltage, gas mixing, etc.). Recently, intensive efforts were taken to investigate now the effect of different RF resonant modes to the plasma structure. Comparing to the 2002 experiment, this campaign used wider instrumental stock: CCD camera with a lead pinhole was placed at the injection side allowing X-ray imaging and beam extraction simultaneously. Additionally, Silicon Drift Detector (SDD) and High Purity Germanium (HPGe) detectors were installed to characterize the volumetric X-ray emission rate caused by the warm and hot electron domains. In this paper, detailed comparison study on the two X-ray camera and detector setups and also on the technical and scientific goals of the experiments is presented.

  15. X-ray pinhole camera setups used in the Atomki ECR Laboratory for plasma diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Rácz, R., E-mail: rracz@atomki.hu; Biri, S.; Pálinkás, J. [Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/C, H-4026 Debrecen (Hungary); Mascali, D.; Castro, G.; Caliri, C.; Gammino, S. [Instituto Nazionale di Fisica Nucleare—Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); Romano, F. P. [Instituto Nazionale di Fisica Nucleare—Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); CNR, Istituto per i Beni Archeologici e Monumentali, Via Biblioteca 4, 95124 Catania (Italy)

    2016-02-15

    Imaging of the electron cyclotron resonance (ECR) plasmas by using CCD camera in combination with a pinhole is a non-destructive diagnostics method to record the strongly inhomogeneous spatial density distribution of the X-ray emitted by the plasma and by the chamber walls. This method can provide information on the location of the collisions between warm electrons and multiple charged ions/atoms, opening the possibility to investigate the direct effect of the ion source tuning parameters to the plasma structure. The first successful experiment with a pinhole X-ray camera was carried out in the Atomki ECR Laboratory more than 10 years ago. The goal of that experiment was to make the first ECR X-ray photos and to carry out simple studies on the effect of some setting parameters (magnetic field, extraction, disc voltage, gas mixing, etc.). Recently, intensive efforts were taken to investigate now the effect of different RF resonant modes to the plasma structure. Comparing to the 2002 experiment, this campaign used wider instrumental stock: CCD camera with a lead pinhole was placed at the injection side allowing X-ray imaging and beam extraction simultaneously. Additionally, Silicon Drift Detector (SDD) and High Purity Germanium (HPGe) detectors were installed to characterize the volumetric X-ray emission rate caused by the warm and hot electron domains. In this paper, detailed comparison study on the two X-ray camera and detector setups and also on the technical and scientific goals of the experiments is presented.

  16. Toroidal inhomogeneity of plasma density fluctuations during ECR plasma heating in the L-2M stellarator

    Science.gov (United States)

    Batanov, G. M.; Borzosekov, V. D.; Kolik, L. V.; Konchekov, E. M.; Malakhov, D. V.; Petrov, A. E.; Sarksyan, K. A.; Stepakhin, V. D.; Kharchev, N. K.

    2017-11-01

    Correlation between short-wavelength ( k ⊥ ≈ 20-30 cm-1) and long-wavelength ( k ⊥ ≈ 1-2 cm-1) plasma density fluctuations in two poloidal cross sections of the stellarator chamber separated by 1/14 or 5/14 of the torus perimeter was studied using collective scattering of radiation of two 75-GHz gyrotrons and radiation of a 37-GHz Doppler reflectometer at an ECR heating power density of 1.6-3.2 MW/m3. It is found that excitation of turbulent fluctuations is bursty in character and that fluctuations excited in different L-2M cross sections are uncorrelated. It is shown that the energy of turbulent fluctuations is modulated by a low frequency of 5-20 kHz. An idea is put forward that anomalous transport is toroidally inhomogeneous.

  17. Particle flux at the outlet of an Ecr plasma source; Flujos de particulas a la salida de una fuente de plasma ECR

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez T, C.; Gonzalez D, J. [ININ, Departamento de Fisica, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    The necessity of processing big material areas this has resulted in the development of plasma sources with the important property to be uniform in these areas. Also the continuous diminution in the size of substrates to be processed have stimulated the study of models which allow to predict the control of energy and the density of the ions and neutral particles toward the substrate. On the other hand, there are other applications of the plasma sources where it is very necessary to understand the effects generated by the energetic fluxes of ions and neutrals. These fluxes as well as another beneficial effects can improve the activation energy for the formation and improvement of the diffusion processes in the different materials. In this work, using the drift kinetic approximation is described a model to calculate the azimuthal and radial fluxes in the zone of materials processing of an Ecr plasma source type. The results obtained are compared with experimental results. (Author)

  18. Spatial structures of intermittent local electron flux in a linear ECR plasma

    Science.gov (United States)

    Yoshimura, Shinji; Terasaka, Kenichiro; Tanaka, Eiki; Aramaki, Mitsutoshi; Tanaka, Masayoshi Y.

    2013-10-01

    Spontaneous generation of intermittent local electron flux has been observed in a linear electron-cyclotron-resonance (ECR) plasma produced in the HYPER-I device (NIFS, Japan). Statistical analysis of temporal variation of floating potential on a Langmuir probe revealed that the phenomenon is characterized by a stationary Poisson process. In order to measure 2D spatial structures of the electron flux, the High-Impedance Wire Grid (HIWG) that consists of 16 electrically-floated electrodes (8 horizontal and 8 vertical) has been developed. By evaluating the magnitude of the flux at each lattice point as the geometric mean of the signal amplitudes on corresponding pair of electrodes at a given time, a snapshot of 2D intensity distribution of the electron flux can be reconstructed. The electron flux has a circular cross-section of which diameter is typically about 30 mm. End view images taken by an ICCD camera with an optical filter also show local enhancement of line emissions of ions and neutrals in the circular region in which the intermittent electron flux enhancement occurs. This work was supported by JSPS KAKENHI Grant Number 24540544.

  19. Electromagnetic diagnostics of ECR-Ion Sources plasmas: optical/X-ray imaging and spectroscopy

    Science.gov (United States)

    Mascali, D.; Castro, G.; Altana, C.; Caliri, C.; Mazzaglia, M.; Romano, F. P.; Leone, F.; Musumarra, A.; Naselli, E.; Reitano, R.; Torrisi, G.; Celona, L.; Cosentino, L. G.; Giarrusso, M.; Gammino, S.

    2017-12-01

    Magnetoplasmas in ECR-Ion Sources are excited from gaseous elements or vapours by microwaves in the range 2.45–28 GHz via Electron Cyclotron Resonance. A B-minimum, magnetohydrodynamic stable configuration is used for trapping the plasma. The values of plasma density, temperature and confinement times are typically ne= 1011‑1013 cm‑3, 01 eVSilicon Drift detectors with high energy resolution of 125 eV at 5.9 keV have been used for the characterization of plasma emission at 02magnetic field profile (they are critical for high-power proton sources).

  20. Hydrogen Recovery by ECR Plasma Pyrolysis of Methane Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Development of a microgravity and hypogravity compatible microwave plasma methane pyrolysis reactor is proposed to recover hydrogen which is lost as methane in the...

  1. Modelling RF-plasma interaction in ECR ion sources

    Science.gov (United States)

    Mascali, David; Torrisi, Giuseppe; Galatà, Alessio; Sorbello, Gino; Castro, Giuseppe; Celona, Luigi; Lega, Lorenzo; Leonardi, Ornella; Mazzaglia, Maria; Naselli, Eugenia; Neri, Lorenzo; Gammino, Santo

    2017-10-01

    This paper describes three-dimensional self-consistent numerical simulations of wave propagation in magnetoplasmas of Electron cyclotron resonance ion sources (ECRIS). Numerical results can give useful information on the distribution of the absorbed RF power and/or efficiency of RF heating, especially in the case of alternative schemes such as mode-conversion based heating scenarios. Ray-tracing approximation is allowed only for small wavelength compared to the system scale lengths: as a consequence, full-wave solutions of Maxwell-Vlasov equation must be taken into account in compact and strongly inhomogeneous ECRIS plasmas. This contribution presents a multi-scale temporal domains approach for simultaneously including RF dynamics and plasma kinetics in a "cold-plasma", and some perspectives for "hot-plasma" implementation. The presented results rely with the attempt to establish a modal-conversion scenario of OXB-type in double frequency heating inside an ECRIS testbench.

  2. Influence of ECR-RF plasma modification on surface and thermal properties of polyester copolymer

    Directory of Open Access Journals (Sweden)

    Fray Miroslawa El

    2015-12-01

    Full Text Available In this paper we report a study on influence of radio-frequency (RF plasma induced with electron cyclotron resonance (ECR on multiblock copolymer containing butylene terephthalate hard segments (PBT and butylene dilinoleate (BDLA soft segments. The changes in thermal properties were studied by DSC. The changes in wettability of PBT-BDLA surfaces were studied by water contact angle (WCA. We found that ECR-RF plasma surface treatment for 60 s led to decrease of WCA, while prolonged exposure of plasma led to increase of WCA after N2 and N2O2 treatment up to 70°–80°. The O2 reduced the WCA to 50°–56°. IR measurements confirmed that the N2O2 plasma led to formation of polar groups. SEM investigations showed that plasma treatment led to minor surfaces changes. Collectively, plasma treatment, especially O2, induced surface hydrophilicity what could be beneficial for increased cell adhesion in future biomedical applications of these materials.

  3. Modelling RF-plasma interaction in ECR ion sources

    Directory of Open Access Journals (Sweden)

    Mascali David

    2017-01-01

    Full Text Available This paper describes three-dimensional self-consistent numerical simulations of wave propagation in magnetoplasmas of Electron cyclotron resonance ion sources (ECRIS. Numerical results can give useful information on the distribution of the absorbed RF power and/or efficiency of RF heating, especially in the case of alternative schemes such as mode-conversion based heating scenarios. Ray-tracing approximation is allowed only for small wavelength compared to the system scale lengths: as a consequence, full-wave solutions of Maxwell-Vlasov equation must be taken into account in compact and strongly inhomogeneous ECRIS plasmas. This contribution presents a multi-scale temporal domains approach for simultaneously including RF dynamics and plasma kinetics in a “cold-plasma”, and some perspectives for “hot-plasma” implementation. The presented results rely with the attempt to establish a modal-conversion scenario of OXB-type in double frequency heating inside an ECRIS testbench.

  4. Microwave frequency sweep interferometer for plasma density measurements in ECR ion sources: Design and preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Torrisi, Giuseppe [INFN - Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); University Mediterranea of Reggio Calabria, Reggio Calabria (Italy); Mascali, David; Neri, Lorenzo; Leonardi, Ornella; Celona, Luigi; Castro, Giuseppe; Agnello, Riccardo; Caruso, Antonio; Passarello, Santi; Longhitano, Alberto; Gammino, Santo [INFN - Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Sorbello, Gino [INFN - Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); University of Catania, Catania, Italy and INFN-LNS, Catania (Italy); Isernia, Tommaso [University Mediterranea of Reggio Calabria, Reggio Calabria (Italy)

    2016-02-15

    The Electron Cyclotron Resonance Ion Sources (ECRISs) development is strictly related to the availability of new diagnostic tools, as the existing ones are not adequate to such compact machines and to their plasma characteristics. Microwave interferometry is a non-invasive method for plasma diagnostics and represents the best candidate for plasma density measurement in hostile environment. Interferometry in ECRISs is a challenging task mainly due to their compact size. The typical density of ECR plasmas is in the range 10{sup 11}–10{sup 13} cm{sup −3} and it needs a probing beam wavelength of the order of few centimetres, comparable to the chamber radius. The paper describes the design of a microwave interferometer developed at the LNS-INFN laboratories based on the so-called “frequency sweep” method to filter out the multipath contribution in the detected signals. The measurement technique and the preliminary results (calibration) obtained during the experimental tests will be presented.

  5. Microwave ECR plasma electron flood for low pressure wafer charge neutralization

    Energy Technology Data Exchange (ETDEWEB)

    Vanderberg, Bo; Nakatsugawa, Tomoya; Divergilio, William [Axcelis Technologies Inc., 108 Cherry Hill Drive, Beverly, MA 01915 (United States)

    2012-11-06

    Modern ion implanters typically use dc arc discharge Plasma Electron Floods (PEFs) to neutralize wafer charge. The arc discharge requires using at least some refractory metal hardware, e.g. a thermionically emitting filament, which can be undesirable in applications where no metallic contamination is critical. rf discharge PEFs have been proposed to mitigate contamination risks but the gas flows required can result in high process chamber pressures. Axcelis has developed a microwave electron cyclotron resonance (ECR) PEF to provide refractory metals contamination-free wafer neutralization with low gas flow requirement. Our PEF uses a custom, reentrant cusp magnet field providing ECR and superior electron confinement. Stable PEF operation with extraction slits sized for 300 mm wafers can be attained at Xe gas flows lower than 0.2 sccm. Electron extraction currents can be as high as 20 mA at absorbed microwave powers < 70 W. On Axcelis' new medium current implanter, plasma generation has proven robust against pressure transients caused by, for example, photoresist outgassing by high power ion beams. Charge monitor and floating potential measurements along the wafer surface corroborate adequate wafer charge neutralization for low energy, high current ion beams.

  6. High Growth Rate Deposition of Hydrogenated Amorphous Silicon-Germanium Films and Devices Using ECR-PECVD

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yong [Iowa State Univ., Ames, IA (United States)

    2002-01-01

    Hydrogenated amorphous silicon germanium films (a-SiGe:H) and devices have been extensively studied because of the tunable band gap for matching the solar spectrum and mature the fabrication techniques. a-SiGe:H thin film solar cells have great potential for commercial manufacture because of very low cost and adaptability to large-scale manufacturing. Although it has been demonstrated that a-SiGe:H thin films and devices with good quality can be produced successfully, some issues regarding growth chemistry have remained yet unexplored, such as the hydrogen and inert-gas dilution, bombardment effect, and chemical annealing, to name a few. The alloying of the SiGe introduces above an order-of-magnitude higher defect density, which degrades the performance of the a-SiGe:H thin film solar cells. This degradation becomes worse when high growth-rate deposition is required. Preferential attachment of hydrogen to silicon, clustering of Ge and Si, and columnar structure and buried dihydride radicals make the film intolerably bad. The work presented here uses the Electron-Cyclotron-Resonance Plasma-Enhanced Chemical Vapor Deposition (ECR-PECVD) technique to fabricate a-SiGe:H films and devices with high growth rates. Helium gas, together with a small amount of H2, was used as the plasma species. Thickness, optical band gap, conductivity, Urbach energy, mobility-lifetime product, I-V curve, and quantum efficiency were characterized during the process of pursuing good materials. The microstructure of the a-(Si,Ge):H material was probed by Fourier-Transform Infrared spectroscopy. They found that the advantages of using helium as the main plasma species are: (1) high growth rate--the energetic helium ions break the reactive gas more efficiently than hydrogen ions; (2) homogeneous growth--heavy helium ions impinging on the surface promote the surface mobility of the reactive radicals, so that heteroepitaxy growth as clustering of Ge and Si, columnar structure are

  7. Study of hydrogen ECR plasma in a simple mirror magnetic trap heated by 75 GHz pulsed gyrotron radiation

    Science.gov (United States)

    Skalyga, V. A.; Izotov, I. V.; Sidorov, A. V.; Golubev, S. V.; Razin, S. V.

    2017-03-01

    Plasma of electron cyclotron resonance (ECR) discharge sustained by millimeter wave radiation is widely used for production of ion beams of different kind. The main trend in ECR ion sources development nowadays is an increase of frequency and power of microwave heating. The most advanced systems use gyrotrons in 24-60 GHz frequency range. In previous studies at IAP RAS it was demonstrated that ECR source SMIS 37 (Simple Mirror Ion Source) with 37.5 GHz heating operating in quasigasdynamic regime of plasma confinement is able to produce proton and deuteron beams with ion current density about 700 mA/cm2. As the next step of these investigations plasma properties of the discharge sustained by 75 GHz radiation have been studied. Plasma density and electron temperature were determined using spectroscopic and Langmuir probe techniques. It was demonstrated that plasma density could reach values close to 1014 cm-3 and that is of great interest for further development of high current ion sources for various applications.

  8. Charge state distribution studies of pure and oxygen mixed krypton ECR plasma - signature of isotope anomaly and gas mixing effect.

    Science.gov (United States)

    Kumar, Pravin; Mal, Kedar; Rodrigues, G

    2016-11-01

    We report the charge state distributions of the pure, 25% and 50% oxygen mixed krypton plasma to shed more light on the understanding of the gas mixing and the isotope anomaly [A. G. Drentje, Rev. Sci. Instrum. 63 (1992) 2875 and Y Kawai, D Meyer, A Nadzeyka, U Wolters and K Wiesemann, Plasma Sources Sci. Technol. 10 (2001) 451] in the electron cyclotron resonance (ECR) plasmas. The krypton plasma was produced using a 10 GHz all-permanent-magnet ECR ion source. The intensities of the highly abundant four isotopes, viz. 82 Kr (~11.58%), 83 Kr (~11.49%), 84 Kr (~57%) and 86 Kr (17.3%) up to ~ +14 charge state have been measured by extracting the ions from the plasma and analysing them in the mass and the energy using a large acceptance analyzer-cum-switching dipole magnet. The influence of the oxygen gas mixing on the isotopic krypton ion intensities is clearly evidenced beyond +9 charge state. With and without oxygen mixing, the charge state distribution of the krypton ECR plasma shows the isotope anomaly with unusual trends. The anomaly in the intensities of the isotopes having quite closer natural abundance, viz. 82 Kr, 86 Kr and 83 Kr, 86 Kr is prominent, whereas the intensity ratio of 86 Kr to 84 Kr shows a weak signature of it. The isotope anomaly tends to disappear with increasing oxygen mixing in the plasma. The observed trends in the intensities of the krypton isotopes do not follow the prediction of linear Landau wave damping in the plasma. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  9. ECR plasma synthesis of silicon nitride films on GaAs and InSb

    Energy Technology Data Exchange (ETDEWEB)

    Barbour, J.C.; Lovejoy, M.L.; Ashby, C.I.H.; Howard, A.J.; Custer, J.S.; Shul, R.J.

    1993-12-31

    Growth of high-quality dielectric films from Electron Cyclotron Resonance (ECR) plasmas provides for low-temperature surface passivation of compound semiconductors. Silicon nitride (SiN{sub x}) films were grown at temperatures from 30 to 250 C on GaAs substrates. Stress in films was measured as a function of bias applied during growth (varied from 0 to 200 V), and of sample annealing treatments. Composition profiles of the samples were measured using ion beam analysis. The GaAs photoluminescence (PL) signal after SiN{sub x} growth without an applied bias (ion energy {congruent}30 eV) was twice as large as the PL signal from the cleaned GaAs substrate. The PL signal from samples biased at -50 and -100 V indicated that damage degraded the passivation quality, while atomic force microscopy of these samples showed a three fold increase in rms surface roughness relative to unbiased samples. The sample grown with a bias of -200 V showed the largest reduction in film stress but also the smallest PL signal.

  10. A New Broadband Microwave Frequency Device for Powering ECR Ion Sources

    CERN Document Server

    Kawai, Yoko; Liu, Yuan

    2005-01-01

    The multiple discrete frequency technique has been used to improve the performance of conventional B-field configuration ECR ion sources. However, the practical application of this technique is very costly, requiring multiple independent single-frequency rf power supplies and complicated rf injection systems. Broadband sources of rf power offer a low-cost and more effective method for increasing the physical size of the ECR zone within these ion sources. An Additive White Gaussian Noise Generator (AWGNG) system for injecting broadband rf power into these ion sources has been developed in conjunction with a commercial firm. The noise generator, in combination with an external oscillator and a traveling wave tube amplifier, can be used to generate broadband rf power without modifying the injection system. The AWGNG and its use for enhancing the performance of conventional B-field configuration ECR ion sources will be described.

  11. PECVD/ECR/HWCVD Multichamber System with Robotic Substrate Handling System for deposition of Thin Film Electronic Devices

    Science.gov (United States)

    Rava, P.

    2012-11-01

    The present work reports on progress in the design of modular UHV cluster tool multichamber systems. A wide range of processes has been implemented in the Deposition Process Chambers (DPC's), including rf-PECVD, vhf-PECVD, ECR-PECVD and HWCVD. A wide range of intrinsic and doped amorphous and microcrystalline silicon and silicon alloy materials have been produced and have been used in the fabrication of several types of electronic devices such as solar cells, Light Emitting Devices (LED's), Thin Film Transistors (TFT's), etc. using multichamber systems at several laboratories worldwide.

  12. Complex of lithium and tungsten limiters for 3 MW of ECR plasma heating in T-10 tokamak. Design, first results

    Science.gov (United States)

    Lyublinski, I. E.; Vertkov, A. V.; Zharkov, M. Yu.; Mirnov, S. V.; Vershkov, V. A.; Glazyuk, Ya. V.; Notkin, G. E.; Grashin, S. A.; Kislov, A. Ya.; Komov, A. T.

    2017-06-01

    A complex of tungsten and lithium limiters is developed. It is expected that application of W as a plasma facing material will allow excluding carbon influx into the vacuum chamber. An additional Li limiter, arranged in the shadow of the W one, will be used as a Li source. The parameters and design of limiters are presented. The plasma facing surface of the Li limiter is constructed to make use of a capillary-porous system (CPS). The porous matrix of the CPS provides stability of liquid Li surface under magnetohydrodinamic force effects, and facilitates its constant renewal due to capillary forces. It is shown that the upgrade of limiters in tokamak Т-10 will allow the provision of electron cyclotron resonance (ECR) plasma heating with power up to 3 MW at reasonable Li flux. The first results on Li-W experiments with ECR heating are presented and discussed. Li limiter design and limiter arrangement configuration for a steady state operating tokamak with a closed cycle of lithium circulation are considered.

  13. Enhanced TiC/SiC Ohmic contacts by ECR hydrogen plasma pretreatment and low-temperature post-annealing

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Bingbing [School of Electronic Science and Technology, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian 116024 (China); Qin, Fuwen [State Key Laboratory of Material Modification by Laser, Ion and Electron Beam (Ministry of Education), Dalian University of Technology, Dalian 116024 (China); Wang, Dejun, E-mail: dwang121@dlut.edu.cn [School of Electronic Science and Technology, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian 116024 (China)

    2015-11-15

    Highlights: • Low-temperature ECR microwave hydrogen plasma were pretreated for moderately doped (1 × 10{sup 18} cm{sup −3}) SiC surfaces. • The relationship among Ohmic properties, the SiC surface properties and TiC/SiC interface properties were established. • Interface band structures were analyzed to elucidate the mechanism by which the Ohmic contacts were formed. - Abstract: We proposed an electronic cyclotron resonance (ECR) microwave hydrogen plasma pretreatment (HPT) for moderately doped (1 × 10{sup 18} cm{sup −3}) SiC surfaces and formed ideal TiC/SiC Ohmic contacts with significantly low contact resistivity (1.5 × 10{sup −5} Ω cm{sup 2}) after low-temperature annealing (600 °C). This is achieved by reducing barrier height at TiC/SiC interface because of the release of pinned Fermi level by surface flattening and SiC surface states reduction after HPT, as well as the generation of donor-type carbon vacancies, which reduced the depletion-layer width for electron tunneling after annealing. Interface band structures were analyzed to elucidate the mechanism of Ohmic contact formations.

  14. COUNTERROTATING PLASMA DEVICE

    Science.gov (United States)

    Halbach, K.; Baker, W.R.; Veron, D.

    1963-07-01

    An ion-electron plasma device having a conductive, cylindrical casing provided with an axially directed magneticmirror-type field is described. An axially aligned tubular electrode is disposed at each end of the casing with oppositely directed radial electric fields provided between each electrode and the casing. Simultaneous pulses of gas, injected from the inner end of each of the electrodes, become ionized and oppositely rotating plasma bodies are formed. The magnetic mirrors repel the plasma bodies and cause them to collide in the region between the mirrors. The opposite directions of rotation of the plasma bodies cause very high currents to flow therebetween and consequent heating occurs. (AEC)

  15. ROTATING PLASMA DEVICE

    Science.gov (United States)

    Boyer, K.; Hammel, J.E.; Longmire, C.L.; Nagle, D.E.; Ribe, F.L.; Tuck, J.L.

    1961-10-24

    ABS>A method and device are described for obtaining fusion reactions. The basic concept is that of using crossed electric and magnetic fields to induce a plasma rotation in which the ionized particles follow a circumferential drift orbit on wldch a cyclotron mode of motion is superimposed, the net result being a cycloidal motion about the axis of symmetry. The discharge tube has a radial electric field and a longitudinal magnetic field. Mirror machine geometry is utilized. The device avoids reliance on the pinch effect and its associated instability problems. (AEC)

  16. Magnetic properties of Co-N films deposited by ECR nitrogen/argon plasma with DC negative-biased Co target

    Energy Technology Data Exchange (ETDEWEB)

    Li, H.; Zhang, Y.C.; Yang, K.; Liu, H.X.; Zhu, X.D., E-mail: xdzhu@ustc.edu.cn; Zhou, H.Y.

    2017-06-01

    Highlights: • A new method of synthesizing Co-N films containing Co{sub 4}N phase. • Tunable magnetic properties achieved in ECR plasma CVD. • The change of magnetic properties is related to atoms mobility on substrate and the concentration of active species in plasma vapor. - Abstract: By introducing DC negative-biased Co target in the Electron Cyclotron Resonance (ECR) nitrogen/argon plasma, the Co-N films containing Co{sub 4}N phase were synthesized on Si(100) substrate. Effects of processing parameters on magnetic properties of the films are investigated. It is found that magnetic properties of Co-N films vary with N{sub 2}/Ar flow ratio, substrate temperature, and target biasing voltage. The saturation magnetization M{sub s} decreased by increasing the N{sub 2}/Ar gas flow ratio or decreasing target biasing voltage, while the coercive field H{sub c} increased, which is ascribed to the variation of relative concentration for N or Co active species in plasma vapor. The magnetic properties present complex dependency with growth temperature, which is related to the atom mobility on the substrate affected by the growth temperature. This study exhibits a potential of ECR plasma chemical vapor deposition to synthesize the interstitial compounds and tune magnetic properties of films.

  17. Descriptions of a linear device developed for research on advanced plasma imaging and dynamics.

    Science.gov (United States)

    Chung, J; Lee, K D; Seo, D C; Nam, Y U; Ko, W H; Lee, J H; Choi, M C

    2009-10-01

    The research on advanced plasma imaging and dynamics (RAPID) device is a newly developed linear electron cyclotron resonance (ECR) plasma device. It has a variety of axial magnetic field profiles provided by eight water-cooled magnetic coils and two dc power supplies. The positions of the magnetic coils are freely adjustable along the axial direction and the power supplies can be operated with many combinations of electrical wiring to the coils. A 6 kW 2.45 GHz magnetron is used to produce steady-state ECR plasmas with central magnetic fields of 875 and/or 437.5 G (second harmonic). The cylindrical stainless steel vacuum chamber is 300 mm in diameter and 750 mm in length and has eight radial and ten axial ports including 6-in. and 8-in. viewing windows for heating and diagnostics. Experimental observation of ECR plasma heating has been recently carried out during the initial plasma operation. The main diagnostic systems including a 94 GHz heterodyne interferometer, a high-resolution 25 channel one-dimensional array spectrometer, a single channel survey spectrometer, and an electric probe have been also prepared. The RAPID device is a flexible simulator for the understanding of tokamak edge plasma physics and new diagnostic system development. In this work, we describe the RAPID device and initial operation results.

  18. Plasma devices for hydrocarbon reformation

    KAUST Repository

    Cha, Min Suk

    2017-02-16

    Plasma devices for hydrocarbon reformation are provided. Methods of using the devices for hydrocarbon reformation are also provided. The devices can include a liquid container to receive a hydrocarbon source, and a plasma torch configured to be submerged in the liquid. The plasma plume from the plasma torch can cause reformation of the hydrocarbon. The device can use a variety of plasma torches that can be arranged in a variety of positions in the liquid container. The devices can be used for the reformation of gaseous hydrocarbons and/or liquid hydrocarbons. The reformation can produce methane, lower hydrocarbons, higher hydrocarbons, hydrogen gas, water, carbon dioxide, carbon monoxide, or a combination thereof.

  19. Plasma confinement during ECR heating with a volume power density of 3 mW/m3 at the L-2M stellarator

    Science.gov (United States)

    Meshcheryakov, A. I.; Batanov, G. M.; Borzosekov, V. D.; Grebenshchikov, S. E.; Grishina, I. A.; Kharchev, N. K.; Kholnov, Yu V.; Kolik, L. V.; Konchekov, E. M.; Kovrizhnykh, L. M.; Letunov, A. A.; Logvinenko, V. P.; Malakhov, D. V.; Petrov, A. E.; Sarksyan, K. A.; Shchepetov, S. V.; Skvortsova, N. N.; Stepakhin, V. D.; Tereshchenko, M. A.; Vafin, I. Yu; Vasilkov, D. G.

    2017-10-01

    The experiments on ECR plasma heating were carried out at the L-2M stellarator at very high volume power density (up to 3.0 MW/m3). Under these conditions, non-monotonous hollow density profiles were measured. At the maximum heating power of P = 0.75 MW, the concavity in the axial region becomes drastic n e(0)/n e max = 0.5. In these experiments, plasma temperature profiles measured in the axial plasma region r/a p stellarator. The measured energy lifetime is generally consistent with that determined from the international LHD scaling.

  20. Ion beam extraction from a matrix ECR plasma source by discrete ion-focusing effect

    DEFF Research Database (Denmark)

    Stamate, Eugen; Draghici, Mihai

    2010-01-01

    with high current densities that can treat surfaces placed adjacent to the extraction region. This work introduces a new phenomenology for ion beam extraction using the discrete ion-focusing effect associated with three-dimensional plasma-sheath-lenses [1, 2]. Experiments are performed in a matrix......Torr and plasma densities around 1016 m-3. A rectangular plasma-sheath-lens is created by an electrode-insulator interface designed by finite element simulations. The discrete ion-focusing effect deflects the ions to and extraction aperture on the electrode. A linearly distributed positive ion beam is extracted......Positive or negative ion beams extracted from plasma are used in a large variety of surface functionalization techniques such as implantation, etching, surface activation, passivation or oxidation. Of particular importance is the surface treatment of materials sensitive to direct plasma exposure...

  1. Silicon nitride layers obtained by ECR PECVD

    NARCIS (Netherlands)

    Isai, I.G.; Holleman, J.; Woerlee, P.H.; Wallinga, Hans

    2002-01-01

    It has been found that good quality silicon nitride films can be deposited at room temperature, with an alternate electron cyclotron resonance (ECR) plasma source, called multipolar ECR. The effects of several deposition conditions on physical and electrical properties were studied in order to

  2. Characterization of film surface treated with ECR plasma by Doppler broadening

    CERN Document Server

    Nishijima, S; Hirata, K; Kobayashi, Y; Honda, Y; Tagawa, S

    2000-01-01

    Doppler broadened positron annihilation measurements were carried out using the positron beam technique on plasma treated polyethylene films as a function of incident positron energy. In addition, surface properties of the treated films also have been measured using other conventional techniques such as FT-IR, SEM and AFM. The surface tension of the films was also determined using sessile drop method. The S-parameter is seen to decrease on the surface upon plasma treatment that introduces polar groups such as hydroxyl and carbonyl on the surface. The results are discussed.

  3. Low hydrogen content silicon nitride films deposited at room temperature with a multipolar ECR plasma source

    NARCIS (Netherlands)

    Isai, I.G.; Holleman, J.; Wallinga, Hans; Woerlee, P.H.

    2004-01-01

    Silicon nitride layers with very low hydrogen content (less than 1 atomic percent) were deposited at near room temperature, from N2 and SiH4, with a multipolar electron cyclotron resonance plasma. The influences of pressure and nitrogen flow rate on physical and electrical properties were studied in

  4. Optimization of ECR-breakdown and plasma discharge formation on T-10 tokamak, using X-mode second harmonic of ECR.

    Directory of Open Access Journals (Sweden)

    Roy I.

    2012-09-01

    Full Text Available In order to obtain breakdown and suitable plasma parameters for low-voltage OH start-up, high level of EC-power was injected into T-10 tokamak. Input HF-power was varied in the range of 0.15–1.0 MW. Two HF-launcher systems with different output beams allowed to inject EC-waves with maximum power density 0.25 MW/cm2 and 0.01 MW/cm2. Dependence of breakdown time delay on HF-power was obtained. It was shown, that optimal plasma parameters were achieved in presence of plasma equilibrium currents I=3 kA (input HF-power=1.0 MW. Electron temperature Te=100÷150 eV and electron density ne=5·1012 cm−3 was measured in these discharges. These parameters remained constant during full HF-pulse-length.

  5. Plasma Based Devices

    National Research Council Canada - National Science Library

    Gundersen, M

    2001-01-01

    .... Energy-efficient plasma-based technologies, supported through this grant, are now under commercial investigation for pollution abatement, and have potential for reduced emissions, higher efficiencies...

  6. Modelling of new generation plasma optical devices

    Directory of Open Access Journals (Sweden)

    Litovko Irina V.

    2016-06-01

    Full Text Available The paper presents new generation plasma optical devices based on the electrostatic plasma lens configuration that opens a novel attractive possibility for effective high-tech practical applications. Original approaches to use of plasma accelerators with closed electron drift and open walls for the creation of a cost-effective low-maintenance plasma lens with positive space charge and possible application for low-cost, low-energy rocket engine are described. The preliminary experimental, theoretical and simulation results are presented. It is noted that the presented plasma devices are attractive for many different applications in the state-of-the-art vacuum-plasma processing.

  7. Dry Etching Characteristics of MOVPE-Grown CdTe Epilayers in CH4, H2, Ar ECR Plasmas

    Science.gov (United States)

    Yasuda, K.; Niraula, M.; Araki, N.; Miyata, M.; Kitagawa, S.; Kojima, M.; Ozawa, J.; Tsubota, S.; Yamaguchi, T.; Agata, Y.

    2017-09-01

    Dry etching characteristics of single crystal (100) CdTe epitaxial layers grown on GaAs substrates were studied using CH4, H2, and Ar as process gases in an electron cyclotron resonance plasma. A smooth and anisotropic etching was obtained with CH4, H2, and Ar. No hydrocarbon polymer was found on the etched surface, which was confirmed by x-ray photoelectron spectroscopy measurement. Etching of the CdTe surface was also possible with H2 and Ar; however, no etching was observed in the absence of H2. Dependence of the etch rate on plasma gas composition and flow rates was studied. Mechanisms of etching with and without CH4 supply were also studied. Etched CdTe layers also showed no deterioration of electrical properties, which was confirmed by photoluminescence measurement at 4.2 K and Hall measurement at 300 K.

  8. Innovative launching schemes in ECR ion sources

    Directory of Open Access Journals (Sweden)

    Torrisi Giuseppe

    2017-01-01

    Full Text Available An optimised RF power delivery in magnetoplasmas of ECR ion sources is crucial in order to provide a cost effective upgrade (plasma density and temperature increase and multiply charged ions production of these machines without recurring to higher and higher magnetic fields, power level and pumping wave frequency. This can be done by following two strategies: a in a pure ECR-heating scenario, by multiplexing different frequencies; b in a modal-conversion scenario, by multiple-launching at different frequencies, controllable angles and polarization. The paper will show two typical cases in both the aforementioned scenarios, as developed at INFN-LNS. Test-benches have been developed on purpose, such as the “Plasma Reactor” and “Flexible Plasma Trap”, and solutions have been proposed also for ion beams current boosting in the injectors of the Superconducting Cyclotron.

  9. Innovative launching schemes in ECR ion sources

    Science.gov (United States)

    Torrisi, Giuseppe; Mascali, David; Sorbello, Gino; Castro, Giuseppe; Naselli, Eugenia; Leonardi, Ornella; Celona, Luigi; Gammino, Santo

    2017-10-01

    An optimised RF power delivery in magnetoplasmas of ECR ion sources is crucial in order to provide a cost effective upgrade (plasma density and temperature increase and multiply charged ions production) of these machines without recurring to higher and higher magnetic fields, power level and pumping wave frequency. This can be done by following two strategies: a) in a pure ECR-heating scenario, by multiplexing different frequencies; b) in a modal-conversion scenario, by multiple-launching at different frequencies, controllable angles and polarization. The paper will show two typical cases in both the aforementioned scenarios, as developed at INFN-LNS. Test-benches have been developed on purpose, such as the "Plasma Reactor" and "Flexible Plasma Trap", and solutions have been proposed also for ion beams current boosting in the injectors of the Superconducting Cyclotron.

  10. Microwave Coupling to ECR and Alternative Heating Methods

    CERN Document Server

    Celona, L.

    2013-12-16

    The Electron Cyclotron Resonance Ion Source (ECRIS) is nowadays the most effective device that can feed particle accelerators in a continuous and reliable way, providing high-current beams of low- and medium-charge-state ions and relatively intense currents for highly charged ions. The ECRIS is an important tool for research with ion beams (in surface, atomic, and nuclear science) while, on the other hand, it implies plasma under extreme conditions and thus constitutes an object of scientific interest in itself. The fundamental aspect of the coupling between the electromagnetic wave and the plasma is hereinafter treated together with some variations to the classical ECR heating mechanism, with particular attention being paid to the frequency tuning effect and two-frequency heating. Considerations of electron and ion dynamics will be presented together with some recent observations connecting the beam shape with the frequency of the electromagnetic wave feeding the cavity. The future challenges of higher-charg...

  11. Deposition of low stress, high transmittance SiC as an x-ray mask membrane using ECR plasma CVD

    CERN Document Server

    Lee, S Y; Lim, S T; Ahn, J H

    1998-01-01

    SiC for x-ray mask membrane is deposited by Electron Cyclotron Resonance plasma Chemical Vapor Deposition from SiH sub 4 /CH sub 4 Ar mixtures. Stoichiometric SiC is deposited at SiH sub 4 /CH sub 4 ratio of 0.4, deposition temperature of 600.deg.C and microwave power of 500 W with +- 5% thickness uniformity, As-deposited film has compressive residual stress, very smooth surface (31 A rms) and high optical transmittance of 90% at 633 nm wavelength. The microstructure of this film consists of the nanocrystalline particle (100 A approx 200A) embedded in amorphous matrix. Residual stress can be turned to tensile stress via Rapid Thermal Annealing in N sub 2 atmosphere, while suppressing structural change during annealing, As a result, smooth (37 A rms) SiC film with moderate tensile stress and high optical transmittance (85% at 633 nm wavelength) is obtained.

  12. Plasma diagnostics of the SIMPA Ecr ion source by X-ray spectroscopy, Collisions of H-like Neon ions with Argon clusters; Diagnostic du plasma de la source d'ions ECR SIMPA par spectroscopie X, Collision d'ions neon hydrogenoides avec des agregats d'argon

    Energy Technology Data Exchange (ETDEWEB)

    Adrouche, N

    2006-09-15

    The first part of this thesis is devoted to the SIMPA ECR ion source characterization, first, I explored the ion source's capacities on the point of view of extracted currents for three elements, argon, krypton and neon. By analyzing the Bremsstrahlung spectra, I determined the electronic temperature in the plasma and the electronic and ionic densities. In a second time, I recorded high resolution X-spectra of argon and krypton plasma's. By taking into account the principal mechanisms of production of a K hole in the ions inside the plasma, I determined the ionic densities of the high charge states of argon. Lastly, I highlighted a correlation between the ions charge states densities with the intensities of extracted currents. The second part of the thesis is devoted to Ne{sup 9+-} argon clusters collisions. First, I presented simple and effective theoretical models allowing to describe the phenomena occurring during a collision, from the point of view of the projectile. I carried out a simulation for a collision of an ion Ne{sup 9+} with an argon cluster of a given size, which has enabled us to know the energy levels populated during the electronic capture and to follow the number of electrons in each projectile shell. Lastly, I presented the first results of a collision between a Ne{sup 9+} beam and argon clusters. These results, have enabled me by using projectile X-ray spectroscopy during the ions-clusters collision, to evidence a strong clustering of targets atoms and to highlight an electronic multi-capture in the projectile ion excited states. (author)

  13. Charge plasma diode - a novel device concept

    NARCIS (Netherlands)

    Rajasekharan, B.; Hueting, Raymond Josephus Engelbart; Salm, Cora; Hoang, T.; Schmitz, Jurriaan

    2008-01-01

    We propose a new device concept called charge plasma (CP) diode [1]. The diodes are with metal/silicided contacts of different workfunctions and thin intrinsic region in between. The workfunctions and layer thicknesses are chosen such that an electron plasma is formed on one side of the silicon body

  14. Microwave produced plasma in a Toroidal Device

    Science.gov (United States)

    Singh, A. K.; Edwards, W. F.; Held, E. D.

    2010-11-01

    A currentless toroidal plasma device exhibits a large range of interesting basic plasma physics phenomena. Such a device is not in equilibrium in a strict magneto hydrodynamic sense. There are many sources of free energy in the form of gradients in plasma density, temperature, the background magnetic field and the curvature of the magnetic field. These free energy sources excite waves and instabilities which have been the focus of studies in several devices in last two decades. A full understanding of these simple plasmas is far from complete. At Utah State University we have recently designed and installed a microwave plasma generation system on a small tokamak borrowed from the University of Saskatchewan, Saskatoon, Canada. Microwaves are generated at 2.45 GHz in a pulsed dc mode using a magnetron from a commercial kitchen microwave oven. The device is equipped with horizontal and vertical magnetic fields and a transformer to impose a toroidal electric field for current drive. Plasmas can be obtained over a wide range of pressure with and without magnetic fields. We present some preliminary measurements of plasma density and potential profiles. Measurements of plasma temperature at different operating conditions are also presented.

  15. High Intensity High Charge State ECR Ion Sources

    CERN Document Server

    Leitner, Daniela

    2005-01-01

    The next-generation heavy ion beam accelerators such as the proposed Rare Isotope Accelerator (RIA), the Radioactive Ion Beam Factory at RIKEN, the GSI upgrade project, the LHC-upgrade, and IMP in Lanzhou require a great variety of high charge state ion beams with a magnitude higher beam intensity than currently achievable. High performance Electron Cyclotron Resonance (ECR) ion sources can provide the flexibility since they can routinely produce beams from hydrogen to uranium. Over the last three decades, ECR ion sources have continued improving the available ion beam intensities by increasing the magnetic fields and ECR heating frequencies to enhance the confinement and the plasma density. With advances in superconducting magnet technology, a new generation of high field superconducting sources is now emerging, designed to meet the requirements of these next generation accelerator projects. The talk will briefly review the field of high performance ECR ion sources and the latest developments for high intens...

  16. Valorization of ECR sources

    CERN Document Server

    2003-01-01

    One way to limit the size of particle accelerators is to use intense multicharged ion beams. Thus, compact, low cost and reliable sources have been developed. These sources are based on the electron cyclotron resonance (ECR) principle and need no cathode nor filament. A prototype named Nanogan has been developed for the Spiral project of the Ganil accelerator (Caen, France). Then, this technology has been transferred toward other research domains and industrial applications, like the ion implantation in micro-electronics components. (J.S.)

  17. Plasma Properties of Microwave Produced Plasma in a Toroidal Device

    Science.gov (United States)

    Singh, Ajay; Edwards, W. F.; Held, Eric

    2011-10-01

    We have modified a small tokamak, STOR-1M, on loan from University of Saskatchewan, to operate as a low-temperature (~5 eV) toroidal plasma machine with externally induced toroidal magnetic fields ranging from zero to ~50 G. The plasma is produced using microwave discharges at relatively high pressures. Microwaves are produced by a kitchen microwave-oven magnetron operating at 2.45 GHz in continuous operating mode, resulting in pulses ~0.5 s in duration. Initial measurements of plasma formation in this device with and without applied magnetic fields are presented. Plasma density and temperature profiles have been measured using Langmuir probes and the magnetic field profile inside the plasma has been obtained using Hall probes. When the discharge is created with no applied toroidal magnetic field, the plasma does not fill the entire torus due to high background pressure. However, when a toroidal magnetic field is applied, the plasma flows along the applied field, filling the torus. Increasing the applied magnetic field seems to aid plasma formation - the peak density increases and the density gradient becomes steeper. Above a threshold magnetic field, the plasma develops low-frequency density oscillations due to probable excitation of flute modes in the plasma.

  18. Comparison of extraction and beam transport simulations with emittance measurements from the ECR ion source venus

    Energy Technology Data Exchange (ETDEWEB)

    Winklehner, D; Todd, D; Benitez, J; Strohmeier, M; Leitner, D [Nuclear Science Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley (United States); Grote, D, E-mail: winklehner@frib.msu.ed [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore (United States)

    2010-12-15

    The versatility of ECR (Electron Cyclotron Resonance) ion sources makes them the injector of choice for many heavy ion accelerators. However, the design of the LEBT (Low Energy Beam Transport) systems for these devices is challenging, because it has to be matched for a wide variety of ions. In addition, due to the magnetic confinement fields, the ion density distribution across the extraction aperture is inhomogeneous and charge state dependent. In addition, the ion beam is extracted from a region of high axial magnetic field, which adds a rotational component to the beam. In this paper the development of a simulation model (in particular the initial conditions at the extraction aperture) for ECR ion source beams is described. Extraction from the plasma and transport through the beam line are then simulated with the particle-in-cell code WARP. Simulations of the multispecies beam containing Uranium ions of charge state 18+ to 42+ and oxygen ions extracted from the VENUS ECR ion source are presented and compared to experimentally obtained emittance values.

  19. Plasma surface interactions in controlled fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Ghendrih, Ph.; Becoulet, M.; Costanzo, L. [and others

    2000-07-01

    This report brings together all the contributions of EURATOM/CEA association to the 14. international conference on plasma surface interactions in controlled fusion devices. 24 papers are presented and they deal mainly with the ergodic divertor and the first wall of Tore-supra tokamak.

  20. Characterization of a linear device developed for research on advanced plasma imaging and dynamicsa)

    Science.gov (United States)

    Chung, J.; Lee, K. D.; Seo, D. C.; Nam, Y. U.; Choi, M. C.

    2010-10-01

    Within the scope of long term research on imaging diagnostics for steady-state plasmas and understanding of edge plasma physics through diagnostics with conventional spectroscopic methods, we have constructed a linear electron cyclotron resonance (ECR) plasma device named Research on Advanced Plasma Imaging and Dynamics (RAPID). It has a variety of axial magnetic field profiles provided by eight water-cooled magnetic coils and two dc power supplies. The positions of the magnetic coils are freely adjustable along the axial direction and the power supplies can be operated with many combinations of electrical wiring to the coils. Here, a 6 kW 2.45 GHz magnetron is used to produce steady-state hydrogen, helium, and argon plasmas with central magnetic fields of 875 and/or 437.5 G (second harmonic). In order to achieve the highest possible plasma performance within the limited input parameters, wall conditioning experiments were carried out. Chamber bake-out was achieved with heating coils that were wound covering the vessel, and long-pulse electron cyclotron heating discharge cleaning was also followed after 4 days of bake-out. A uniform bake-out temperature (150 °C) was achieved by wrapping the vessel in high temperature thermal insulation textile and by controlling the heating coil current using a digital control system. The partial pressure changes were observed using a residual gas analyzer, and a total system pressure of 5×10-8 Torr was finally reached. Diagnostic systems including a millimeter-wave interferometer, a high resolution survey spectrometer, a Langmuir probe, and an ultrasoft x-ray detector were used to provide the evidence that the plasma performance was improved as we desired. In this work, we present characterization of the RAPID device for various system conditions and configurations.

  1. Characterization of a linear device developed for research on advanced plasma imaging and dynamics.

    Science.gov (United States)

    Chung, J; Lee, K D; Seo, D C; Nam, Y U; Choi, M C

    2010-10-01

    Within the scope of long term research on imaging diagnostics for steady-state plasmas and understanding of edge plasma physics through diagnostics with conventional spectroscopic methods, we have constructed a linear electron cyclotron resonance (ECR) plasma device named Research on Advanced Plasma Imaging and Dynamics (RAPID). It has a variety of axial magnetic field profiles provided by eight water-cooled magnetic coils and two dc power supplies. The positions of the magnetic coils are freely adjustable along the axial direction and the power supplies can be operated with many combinations of electrical wiring to the coils. Here, a 6 kW 2.45 GHz magnetron is used to produce steady-state hydrogen, helium, and argon plasmas with central magnetic fields of 875 and/or 437.5 G (second harmonic). In order to achieve the highest possible plasma performance within the limited input parameters, wall conditioning experiments were carried out. Chamber bake-out was achieved with heating coils that were wound covering the vessel, and long-pulse electron cyclotron heating discharge cleaning was also followed after 4 days of bake-out. A uniform bake-out temperature (150 °C) was achieved by wrapping the vessel in high temperature thermal insulation textile and by controlling the heating coil current using a digital control system. The partial pressure changes were observed using a residual gas analyzer, and a total system pressure of 5×10(-8) Torr was finally reached. Diagnostic systems including a millimeter-wave interferometer, a high resolution survey spectrometer, a Langmuir probe, and an ultrasoft x-ray detector were used to provide the evidence that the plasma performance was improved as we desired. In this work, we present characterization of the RAPID device for various system conditions and configurations.

  2. Device for nanoparticle production using plasma methods

    Directory of Open Access Journals (Sweden)

    Bica, Ion

    1999-04-01

    Full Text Available The paper presents a device for nanoparticle production using the method of vaporization of metals and/or the method of thermal decomposition of compounds of metals (oxides, carbonyls, halides, etc. in the plasma of transferred electric are or in plasma jet. The dimensions particles obtained are 3 to 100nm some possible applications.

    Este trabajo presenta un dispositivo destinado a la producción de nanopartículas utilizando métodos de vaporización de metales y/o el método de descomposición de compuestos metálicos (óxidos, carbonatos, halógenos en el plasma del arco transferido o en el chorro de plasma. Se presentan algunas posibles aplicaciones. Las dimensiones de las partículas obtenidas varían entre 3 y 100nm.

  3. Pulsed Plasma Lubrication Device and Method

    Science.gov (United States)

    Hofer, Richard R. (Inventor); Bickler, Donald B. (Inventor); D'Agostino, Saverio A. (Inventor)

    2016-01-01

    Disclosed herein is a lubrication device comprising a solid lubricant disposed between and in contact with a first electrode and a second electrode dimensioned and arranged such that application of an electric potential between the first electrode and the second electrode sufficient to produce an electric arc between the first electrode and the second electrode to produce a plasma in an ambient atmosphere at an ambient pressure which vaporizes at least a portion of the solid lubricant to produce a vapor stream comprising the solid lubricant. Methods to lubricate a surface utilizing the lubrication device in-situ are also disclosed.

  4. Arc plasma devices: Evolving mechanical design from numerical ...

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 80; Issue 4 ... Arcs; air plasma; plasma torch; non-equilibrium plasma; plasma simulation; torch design. ... A recipe for obtaining mechanical design of arc plasma devices from numerical simulation incorporating two-temperature thermal non-equilibrium model is ...

  5. Plasma flow in peripheral region of detached plasma in linear plasma device

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Y., E-mail: hayashi-yuki13@ees.nagoya-u.ac.jp; Ohno, N. [Graduate School of Engineering, Nagoya University, Nagoya, Aichi 464-8603 (Japan); Kajita, S. [EcoTopia Science Institute, Nagoya University, Nagoya, Aichi 464-8603 (Japan); Tanaka, H. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan)

    2016-01-15

    A plasma flow structure is investigated using a Mach probe under detached plasma condition in a linear plasma device NAGDIS-II. A reverse flow along the magnetic field is observed in a steady-state at far-peripheral region of the plasma column in the upstream side from the recombination front. These experimental results indicate that plasma near the recombination front should strongly diffuse across the magnetic field, and it should be transported along the magnetic field in the reverse flow direction. Furthermore, bursty plasma density fluctuations associated with intermittent convective plasma transport are observed in the far-peripheral region of the plasma column in both upstream and downstream sides from the recombination front. Such a nondiffusive transport can contribute to the intermittent reverse plasma flow, and the experimental results indicate that intermittent transports are frequently produced near the recombination front.

  6. Plasma detachment study of high density helium plasmas in the Pilot-PSI device

    NARCIS (Netherlands)

    Hayashi, Y.; Jesko, K.; van der Meiden, H. J.; Vernimmen, J. W. M.; Morgan, T. W.; Ohno, N.; Kajita, S.; Yoshikawa, M.; Masuzaki, S.

    2016-01-01

    We have investigated plasma detachment phenomena of high-density helium plasmas in the linear plasma device Pilot-PSI, which can realize a relevant ITER SOL/Divertor plasma condition. The experiment clearly indicated plasma detachment features such as drops in the plasma pressure and particle flux

  7. Optomechanical devices for deep plasma cancer proteomics.

    Science.gov (United States)

    Kosaka, Priscila M; Calleja, Montserrat; Tamayo, Javier

    2017-09-01

    Most of the cancer deaths could be avoided by early detection of the tumor when it is confined to its primary site and it has not metastasized. To this aim, one of the most promising strategies is the discovery and detection of protein biomarkers shed by the young tumor to the bloodstream. Proteomic technologies, mainly mass spectrometry and multiplexed immunoassays, have rapidly developed during last years with improved limits of detection and multiplexing capability. Unfortunately, these developments together major investments and large international efforts have not resulted into new useful protein biomarkers. Here, we analyze the potential and limitations of current proteomic technologies for detecting protein biomarkers released into circulation by the tumor. We find that these technologies can hardly probe the deepest region of the plasma proteome, at concentrations below the pg/mL level, where protein biomarkers for early cancer detection may exist. This clearly indicates the need of incorporating novel ultrasensitive techniques to the proteomic tool-box that can cover the inaccessible regions of the plasma proteome. We here propose biological detectors based on nanomechanical systems for discovery and detection of cancer protein biomarkers in plasma. We review the modes of operation of these devices, putting our focus on recent developments on nanomechanical sandwich immunoassays and nanomechanical spectrometry. The first technique enables reproducible immunodetection of proteins at concentrations well below the pg/mL level, with a limit of detection on the verge of 10 ag/mL. This technology can potentially detect low abundance tumor-associated proteins in plasma at the very early stages of the tumor. The second technique enables the identification of individual intact proteins by two physical coordinates, the mass and stiffness, instead of the mass-to-charge ratio of the protein constituents. This technology enormously simplifies the identification of

  8. Hydrogen dissociation in the deposition of GaN films with ECR-PECVD process

    Science.gov (United States)

    Fu, S. L.; Wang, C. A.; Ding, L. C.; Qin, Y. X.

    2017-12-01

    The hydrogen dissociation and its effect on the GaN film growth in the ECR-PECVD process are investigated in this paper. We use N2 and trimethylgallium (TMG) as N and Ga sources respectively in the ECR- PECVD process. The results show that the rate of hydrogen dissociation increases with the microwave power and it becomes higher at high microwave power (> 500 W). However, this population increase of the H species dissociated from the TMG gas in ECR plasma is not enough to change the growth condition from Ga-rich to N-rich.

  9. Global numerical modeling of magnetized plasma in a linear device

    DEFF Research Database (Denmark)

    Magnussen, Michael Løiten

    Understanding the turbulent transport in the plasma-edge in fusion devices is of utmost importance in order to make precise predictions for future fusion devices. The plasma turbulence observed in linear devices shares many important features with the turbulence observed in the edge of fusion...... devices, and are easier to diagnose due to lower temperatures and a better access to the plasma. In order to gain greater insight into this complex turbulent behavior, numerical simulations of plasma in a linear device are performed in this thesis. Here, a three-dimensional drift-fluid model is derived...... from first principles for a magnetized plasma in a linear device. To account for the fluctuations at the same level as the background plasma, the traditional split between background and fluctuations has not been made. The model is implemented using the BOUT++ framework and is solved numerically...

  10. Characteristics of MINI ECR ion source

    Energy Technology Data Exchange (ETDEWEB)

    Saitoh, Yuichi; Yokota, Watalu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    A very compact electron cyclotron resonance ion source (MINI ECR) was manufactured to extend available energy ranges of ion beams by applying multiply charged ions to electrostatic accelerators. The magnetic field to confine a plasma is formed only by small permanent magnets and the microwave power up to 15 W is generated by a compact transistor amplifier in order to install the ion source at a narrow high-voltage terminal where the electrical power feed is restricted. The magnet assembly is 12 cm in length and 11 cm in diameter, and forms a mirror field with the maximum strength of 0.55 T. The total power consumption of the source is below 160 W. The performance of the source was tested in a bench stand. The results of Ar, Xe, O, and N ion generation are reported in this paper. (author)

  11. Commissioning of the superconducting ECR ion source VENUS

    Energy Technology Data Exchange (ETDEWEB)

    Leitner, Daniela; Abbott, Steve R.; Dwinell, Roger D.; Leitner, Matthaeus; Taylor, Clyde; Lyneis, Claude M.

    2003-05-15

    VENUS (Versatile ECR ion source for NUclear Science) is a next generation superconducting ECR ion source, designed to produce high current, high charge state ions for the 88-Inch Cyclotron at the Lawrence Berkeley National Laboratory. VENUS also serves as the prototype ion source for the RIA (Rare Isotope Accelerator) front end. The magnetic confinement configuration consists of three superconducting axial coils and six superconducting radial coils in a sextupole configuration. The nominal design fields of the axial magnets are 4T at injection and 3T at extraction; the nominal radial design field strength at the plasma chamber wall is 2T, making VENUS the world most powerful ECR plasma confinement structure. The magnetic field strength has been designed for optimum operation at 28 GHz. The four-year VENUS project has recently achieved two major milestones: The first plasma was ignited in June, the first mass-analyzed high charge state ion beam was extracted in September of 2002. The pa per describes the ongoing commissioning. Initial results including first emittance measurements are presented.

  12. A plasma photonic crystal bandgap device

    Energy Technology Data Exchange (ETDEWEB)

    Wang, B.; Cappelli, M. A. [Stanford Plasma Physics Laboratory, Department of Mechanical Engineering, Stanford University, Stanford, California 94305 (United States)

    2016-04-18

    A fully tunable plasma photonic crystal is used to control the propagation of free space electromagnetic waves in the S to X bands of the microwave spectrum. An array of discharge plasma tubes forms a simple square crystal structure with the individual plasma dielectric constant tuned through variation in the plasma density. We show, through simulations and experiments, that transverse electric mode bandgaps exist, arising from the positive and negative dielectric constant regimes of the plasma, and that the respective bandgap frequencies can be shifted through changing the dielectric constant by varying discharge current density.

  13. In-liquid plasma devices and methods of use thereof

    KAUST Repository

    Cha, Min Suk

    2017-08-10

    Devices and methods for generating a plasma in a liquid are provided. A low- dielectric material can be placed in contact with the liquid to form an interface a distance from an anode. A voltage can be applied across the anode and a cathode submerged in the liquid to produce the plasma. A variety of devices are provided, including for continuous operation. The devices and methods can be used to generate a plasma in a variety of liquids, for example for water treatment, hydrocarbon reformation, or synthesis of nanomaterial.

  14. Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

    Science.gov (United States)

    2012-10-01

    cut fruit surfaces contaminated with migrating microorganisms," Journal of Food Protection, vol. 71, pp. 1619-1625, Aug 2008. [31] H. L. Chen, et...Journal of Refrigeration-Revue Internationale Du Froid, vol. 32, pp. 3-20, Jan 2009. [35] S. Cheruthazhekatt, et al., "Gas plasmas and plasma

  15. Next generation ECR ion sources: First results of the superconducting 28 GHz ECRIS - VENUS

    Energy Technology Data Exchange (ETDEWEB)

    Leitner, D. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 88R0192, Berkeley, CA 94720 (United States)]. E-mail: dleitner@lbl.gov; Lyneis, C.M. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 88R0192, Berkeley, CA 94720 (United States); Abbott, S.R. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 88R0192, Berkeley, CA 94720 (United States); Collins, D. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 88R0192, Berkeley, CA 94720 (United States); Dwinell, R.D. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 88R0192, Berkeley, CA 94720 (United States); Galloway, M.L. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 88R0192, Berkeley, CA 94720 (United States); Leitner, M. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 88R0192, Berkeley, CA 94720 (United States); Todd, D.S. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 88R0192, Berkeley, CA 94720 (United States)

    2005-07-01

    VENUS (Versatile ECR ion source for NUclear Science) is a next generation superconducting ECR ion source, designed to produce high current, high charge state ions for the 88-Inch Cyclotron at the Lawrence Berkeley National Laboratory. VENUS also serves as the prototype ion source for the RIA (rare isotope accelerator) front end. The goal of the VENUS ECR ion source project as the RIA R and D injector is the production of 200 e{mu}A of U{sup 30+}, a high current medium charge state beam. On the other hand, as an injector ion source for the 88-Inch Cyclotron the design objective is the production of 5 e{mu}A of U{sup 48+}, a low current, very high charge state beam. To achieve those ambitious goals, the VENUS ECR ion source has been designed for optimum operation at 28 GHz. The nominal design fields of the axial magnets are 4 T at injection and 3 T at extraction; the nominal radial design field strength at the plasma chamber wall is 2 T, making VENUS currently the world's most powerful ECR plasma confinement structure. Recently, the six year project has made significant progress. In June 2002, the first plasma was ignited at 18 GHz. During 2003, the VENUS ECR ion source was commissioned at 18 GHz, while preparations for 28 GHz operation were being conducted. In May 2004 28 GHz microwave power has been coupled into the VENUS ECR ion source for the first time. Preliminary performance-tests with oxygen, xenon and bismuth at 18 GHz and 28 GHz have shown promising results. Intensities close to or exceeding the RIA requirements have been produced for those few test beams. The paper will briefly describe the design of the VENUS source and its beam analyzing system. Results at 18 GHz and 28 GHz including first emittance measurements will be described.

  16. Arc plasma devices: Evolving mechanical design from numerical ...

    Indian Academy of Sciences (India)

    dynamics and electrical characteristics of a plasma torch are computed in a systematic manner to evaluate ... Arc plasma devices serve as the key components for numerous technological applications. [1]. Processes .... (TK) of the emitting surface, the second one depends on the prevailing electric field (EK). Pramana – J.

  17. The HelCat basic plasma science device

    Science.gov (United States)

    Gilmore, M.; Lynn, A. G.; Desjardins, T. R.; Zhang, Y.; Watts, C.; Hsu, S. C.; Betts, S.; Kelly, R.; Schamiloglu, E.

    2015-01-01

    The Helicon-Cathode(HelCat) device is a medium-size linear experiment suitable for a wide range of basic plasma science experiments in areas such as electrostatic turbulence and transport, magnetic relaxation, and high power microwave (HPM)-plasma interactions. The HelCat device is based on dual plasma sources located at opposite ends of the 4 m long vacuum chamber - an RF helicon source at one end and a thermionic cathode at the other. Thirteen coils provide an axial magnetic field B >= 0.220 T that can be configured individually to give various magnetic configurations (e.g. solenoid, mirror, cusp). Additional plasma sources, such as a compact coaxial plasma gun, are also utilized in some experiments, and can be located either along the chamber for perpendicular (to the background magnetic field) plasma injection, or at one of the ends for parallel injection. Using the multiple plasma sources, a wide range of plasma parameters can be obtained. Here, the HelCat device is described in detail and some examples of results from previous and ongoing experiments are given. Additionally, examples of planned experiments and device modifications are also discussed.

  18. Development of a Rotating Magnetized Plasma Device

    Science.gov (United States)

    Cooke, David; Patton, James; Reid, Remington; Stiles, Ashley; Morrison, Patrik; Koch, Andrei

    2017-10-01

    Momentum coupling in plasma is a mechanism that is central to a wide range of interesting and important phenomena, magnetosphere-ionosphere coupling, solar eruptions, the interaction of an electro-dynamic tether system in the Earth's ionosphere, and the Critical Ionization Velocity (CIV) mechanism are a few examples. One result of the Space Shuttle Tethered Satellite experiment, TSS-1R, was that the current-voltage response of the experiment in all orbit conditions fell into a narrow range of curves when parameterized as a plasma probe [Thompson, GRL,1998]. Another striking result was the lack of dependence on the Alfvén velocity or other electro-magnetic parameters. This result has led us to revisit the understanding of the speed with which an electric field propagates along the magnetic field using EM-PIC simulation and experiments in our new magnetized plasma chamber. Our initial experiment is a rotating plasma using a solenoidal magnetic field and a radial electric field, with pulsed differential rotation of the plasma column to study the strength of coupling and propagation speed. Characteristics of our `first light' rotating plasma will be presented. Supported by Air Force Office Scientific Research 16RVCOR264.

  19. Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

    Science.gov (United States)

    2014-10-01

    6. “Texas A&M University-Corpus Christi researcher fights drug -resistant researcher with plasma technology”, Operating Room Today – OR TODAY Magazine...June 2013. (Link: http://ortoday.com/texas-am-researcher-fights- drug - resistant-cold-plasma-technology/) 7. “Killer “Superbugs” are No Match for...Symposium: Course Design for the Millennial Student, Texas A&M University – Corpus Christi, 2011. (Showcased by the Center for Faculty Excellence

  20. Chaos control and taming of turbulence in plasma devices

    DEFF Research Database (Denmark)

    Klinger, T.; Schröder, C.; Block, D.

    2001-01-01

    . Electric control fields are externally applied to the plasma device and the chaotic or turbulent state is stabilized by only weak perturbations of the plasma equilibrium. The success of this approach is demonstrated in both experiment and numerical simulation and the actual effect of the applied control......Chaos and turbulence are often considered as troublesome features of plasma devices. In the general framework of nonlinear dynamical systems, a number of strategies have been developed to achieve active control over complex temporal or spatio-temporal behavior. Many of these techniques apply...

  1. Parameters of atmospheric plasmas produced by electrosurgical devices

    Science.gov (United States)

    Keidar, Michael; Shashurin, Alexey; Canady, Jerome

    2013-10-01

    Electrosurgical systems are extensively utilized in general surgery, surgical oncology, plastic and reconstructive surgery etc. In this work we study plasma parameters created by electrosurgical system SS-200E/Argon 2 of US Medical Innovations. The maximal length of the discharge plasma column at which the discharge can be sustained was determined as function of discharge power and argon flow rate. Electrical parameters including discharge current and voltage were measured. Recently proposed Rayleigh microwave scattering method for temporally resolved density measurements of small-size atmospheric plasmas was utilized. Simultaneously, evolution of plasma column was observed using intensified charge-coupled device (ICCD) camera.

  2. Advanced Design Concepts for Dense Plasma Focus Devices at LLNL

    Science.gov (United States)

    Povilus, Alexander; Podpaly, Yuri; Cooper, Christopher; Shaw, Brian; Chapman, Steve; Mitrani, James; Anderson, Michael; Pearson, Aric; Anaya, Enrique; Koh, Ed; Falabella, Steve; Link, Tony; Schmidt, Andrea

    2017-10-01

    The dense plasma focus (DPF) is a z-pinch device where a plasma sheath is accelerated down a coaxial railgun and ends in a radial implosion, pinch phase. During the pinch phase, the plasma generates intense, transient electric fields through physical mechanisms, similar to beam instabilities, that can accelerate ions in the plasma sheath to MeV-scale energies on millimeter length scales. Using kinetic modeling techniques developed at LLNL, we have gained insight into the formation of these accelerating fields and are using these observations to optimize the behavior of the generated ion beam for producing neutrons via beam-target interactions for kilojoule to megajoule-scale devices. Using a set of DPF's, both in operation and in development at LLNL, we have explored critical aspects of these devices, including plasma sheath formation behavior, power delivery to the plasma, and instability seeding during the implosion in order to improve the absolute yield and stability of the device. Prepared by LLNL under Contract DE-AC52-07NA27344. Computing support for this work came from the LLNL Institutional Computing Grand Challenge program.

  3. Intrinsic suppression of turbulence in linear plasma devices

    Science.gov (United States)

    Leddy, J.; Dudson, B.

    2017-12-01

    Plasma turbulence is the dominant transport mechanism for heat and particles in magnetised plasmas in linear devices and tokamaks, so the study of turbulence is important in limiting and controlling this transport. Linear devices provide an axial magnetic field that serves to confine a plasma in cylindrical geometry as it travels along the magnetic field from the source to the strike point. Due to perpendicular transport, the plasma density and temperature have a roughly Gaussian radial profile with gradients that drive instabilities, such as resistive drift-waves and Kelvin–Helmholtz. If unstable, these instabilities cause perturbations to grow resulting in saturated turbulence, increasing the cross-field transport of heat and particles. When the plasma emerges from the source, there is a time, {τ }\\parallel , that describes the lifetime of the plasma based on parallel velocity and length of the device. As the plasma moves down the device, it also moves azimuthally according to E × B and diamagnetic velocities. There is a balance point in these parallel and perpendicular times that sets the stabilisation threshold. We simulate plasmas with a variety of parallel lengths and magnetic fields to vary the parallel and perpendicular lifetimes, respectively, and find that there is a clear correlation between the saturated RMS density perturbation level and the balance between these lifetimes. The threshold of marginal stability is seen to exist where {τ }\\parallel ≈ 11{τ }\\perp . This is also associated with the product {τ }\\parallel {γ }* , where {γ }* is the drift-wave linear growth rate, indicating that the instability must exist for roughly 100 times the growth time for the instability to enter the nonlinear growth phase. We explore the root of this correlation and the implications for linear device design.

  4. Aerosol beam-focus laser-induced plasma spectrometer device

    Science.gov (United States)

    Cheng, Meng-Dawn

    2002-01-01

    An apparatus for detecting elements in an aerosol includes an aerosol beam focuser for concentrating aerosol into an aerosol beam; a laser for directing a laser beam into the aerosol beam to form a plasma; a detection device that detects a wavelength of a light emission caused by the formation of the plasma. The detection device can be a spectrometer having at least one grating and a gated intensified charge-coupled device. The apparatus may also include a processor that correlates the wavelength of the light emission caused by the formation of the plasma with an identity of an element that corresponds to the wavelength. Furthermore, the apparatus can also include an aerosol generator for forming an aerosol beam from bulk materials. A method for detecting elements in an aerosol is also disclosed.

  5. Complementary electrowetting devices on plasma-treated fluoropolymer surfaces.

    Science.gov (United States)

    Kim, D Y; Steckl, A J

    2010-06-15

    A reversal of the normal two-fluid competitive (water vs oil) electrowetting (nEW) on dielectric has been achieved by plasma irradiation of the normally hydrophobic fluoropolymer followed by thermal annealing. This process first renders the surface hydrophilic and then returns it to its normal hydrophobic properties as measured by water droplet contact and rolling angles. In the plasma-irradiated and annealed EW device (pEW), the normal two-fluid EW action is reversed after an initial charging step, with the oil layer being displaced at zero voltage and being returned at high voltage. A possible explanation of this effect is a plasma-induced modification of the fluoropolymer, rendering it more susceptible to charge injection and trapping at high voltage. nEW and pEW devices exhibit complementary EW operation, as verified by oil movement and optical transmission. This method can lead to low-power operation of two-fluid EW devices.

  6. Corrosion and wear in plasma electrosurgical devices

    Science.gov (United States)

    Gaspredes, J.; Ryan, T. P.; Stalder, K. R.; Woloszko, J.

    2017-02-01

    Data were previously reported on studies of the effects of electrical discharges on the corrosion and wear of simple, single-wire test devices immersed in isotonic saline 1 . This work showed that there are a wide variety of mechanisms that can explain various aspects of electrode mass loss, even with very simple electrode geometries and operating conditions. It was found that the electrode material composition played an important role. Subsequently, our studies were expanded to include more realistic device geometries and operating conditions. This paper shows the results of studies on wear characteristics of electrodes made from a variety of highly corrosion resistant metals and alloys, including Waspaloy, Hastelloy, Inconel, Havar, Monel, and other pure metals such as Hafnium. All of these metals underwent wear testing under clinically relevant conditions. Depending on the operating conditions, multiple discrete physical and chemical effects were observed at different locations on the surface of an individual millimeter-scale device electrode. Scanning electron microscope (SEM) micrographs, Energy-dispersive X-ray spectroscopy (EDS) and area loss data will be presented for a variety of test conditions and electrode materials.

  7. Plasma response to electron energy filter in large volume plasma device

    Energy Technology Data Exchange (ETDEWEB)

    Sanyasi, A. K.; Awasthi, L. M.; Mattoo, S. K.; Srivastava, P. K.; Singh, S. K.; Singh, R.; Kaw, P. K. [Institute for Plasma Research, Gandhinagar, 382 428 Gujarat (India)

    2013-12-15

    An electron energy filter (EEF) is embedded in the Large Volume Plasma Device plasma for carrying out studies on excitation of plasma turbulence by a gradient in electron temperature (ETG) described in the paper of Mattoo et al. [S. K. Mattoo et al., Phys. Rev. Lett. 108, 255007 (2012)]. In this paper, we report results on the response of the plasma to the EEF. It is shown that inhomogeneity in the magnetic field of the EEF switches on several physical phenomena resulting in plasma regions with different characteristics, including a plasma region free from energetic electrons, suitable for the study of ETG turbulence. Specifically, we report that localized structures of plasma density, potential, electron temperature, and plasma turbulence are excited in the EEF plasma. It is shown that structures of electron temperature and potential are created due to energy dependence of the electron transport in the filter region. On the other hand, although structure of plasma density has origin in the particle transport but two distinct steps of the density structure emerge from dominance of collisionality in the source-EEF region and of the Bohm diffusion in the EEF-target region. It is argued and experimental evidence is provided for existence of drift like flute Rayleigh-Taylor in the EEF plasma.

  8. Current and Perspective Applications of Dense Plasma Focus Devices

    Science.gov (United States)

    Gribkov, V. A.

    2008-04-01

    Dense Plasma Focus (DPF) devices' applications, which are intended to support the main-stream large-scale nuclear fusion programs (NFP) from one side (both in fundamental problems of Dense Magnetized Plasma physics and in its engineering issues) as well as elaborated for an immediate use in a number of fields from the other one, are described. In the first direction such problems as self-generated magnetic fields, implosion stability of plasma shells having a high aspect ratio, etc. are important for the Inertial Confinement Fusion (ICF) programs (e.g. as NIF), whereas different problems of current disruption phenomenon, plasma turbulence, mechanisms of generation of fast particles and neutrons in magnetized plasmas are of great interest for the large devices of the Magnetic Plasma Confinement—MPC (e.g. as ITER). In a sphere of the engineering problems of NFP it is shown that in particular the radiation material sciences have DPF as a very efficient tool for radiation tests of prospect materials and for improvement of their characteristics. In the field of broad-band current applications some results obtained in the fields of radiation material sciences, radiobiology, nuclear medicine, express Neutron Activation Analysis (including a single-shot interrogation of hidden illegal objects), dynamic non-destructive quality control, X-Ray microlithography and micromachining, and micro-radiography are presented. As the examples of the potential future applications it is proposed to use DPF as a powerful high-flux neutron source to generate very powerful pulses of neutrons in the nanosecond (ns) range of its duration for innovative experiments in nuclear physics, for the goals of radiation treatment of malignant tumors, for neutron tests of materials of the first wall, blankets and NFP device's constructions (with fluences up to 1 dpa per a year term), and ns pulses of fast electrons, neutrons and hard X-Rays for brachytherapy.

  9. Commissioning of the superconducting ECR ion source VENUS at 18 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Leitner, Daniela; Abbott, Steven R.; Dwinell, Roger D.; Leitner, Matthaeus; Taylor, Clyde E.; Lyneis, Claude M.

    2004-06-01

    During the last year, the VENUS ECR ion source was commissioned at 18 GHz and preparations for 28 GHz operation are now underway. During the commissioning phase with 18 GHz, tests with various gases and metals have been performed with up to 2000 W RF power. The ion source performance is very promising [1,2]. VENUS (Versatile ECR ion source for Nuclear Science) is a next generation superconducting ECR ion source, designed to produce high current, high charge state ions for the 88-Inch Cyclotron at the Lawrence Berkeley National Laboratory. VENUS also serves as the prototype ion source for the RIA (Rare Isotope Accelerator) front end. The goal of the VENUS ECR ion source project as the RIA R&D injector is the production of 240e{micro}A of U{sup 30+}, a high current medium charge state beam. On the other hand, as an injector ion source for the 88-Inch Cyclotron the design objective is the production of 5e{micro}A of U{sup 48+}, a low current, very high charge state beam. To meet these ambitious goals, VENUS has been designed for optimum operation at 28 GHz. This frequency choice has several design consequences. To achieve the required magnetic confinement, superconducting magnets have to be used. The size of the superconducting magnet structure implies a relatively large plasma volume. Consequently, high power microwave coupling becomes necessary to achieve sufficient plasma heating power densities. The 28 GHz power supply has been delivered in April 2004.

  10. Topics in high voltage pulsed power plasma devices and applications

    Science.gov (United States)

    Chen, Hao

    Pulsed power technology is one of the tools that is used by scientists and engineers nowadays to produce gas plasmas. The transient ultra high power is able to provide a huge pulse of energy which is sometimes greater than the ionization energy of the gas, and therefore separates the ions and electrons to form the plasma. Sometimes, the pulsed power components themselves are plasma devices. For example, the gas type switches can "turn on" the circuit by creating the plasma channel between the switch electrodes. Mini Back Lighted Thyratron, or as we call it, mini-BLT, is one of these gas type plasma switches. The development of the reduced size and weight "mini-BLT" is presented in this dissertation. Based on the operation characteristics testing of the mini-BLT, suggestions of optimizing the design of the switch are proposed. All the factors such as the geometry of the hollow electrodes and switch housing, the gas condition, the optical triggering source, etc. are necessary to consider when we design and operate the mini-BLT. By reducing the diameter of the cylindrical gas path between the electrodes in the BLT, a novel high density plasma source is developed, producing the plasma in the "squeezed" capillary. The pulsed power generator, of course, is inevitably used to provide the ionization energy for hydrogen gas sealed in the capillary. Plasma diagnostics are necessarily analyzed and presented in detail to properly complete and understand the capillary plasma. This high density plasma source (1019 cm-3) has the potential applications in the plasma wakefield accelerator. The resonant oscillation behavior of the particles in plasmas allows for dynamically generated accelerating electric fields that have orders of magnitude larger than those available in the conventional RF accelerators. Finally, the solid state switches are introduced as a comparison to the gas type switch. Pulsed power circuit topologies such as the Marx Bank, magnetic pulse compression and diode

  11. The development of an ECR charge breeder for KEK-JAERI joint RNB project

    CERN Document Server

    Jeong, S C; Tojyo, E; Kawakami, H; Ishiyama, H; Miyatake, H; Enomoto, K; Watanabe, Y; Katayama, I; Nomura, T; Matsuda, M; Osa, A; Ichikawa, S

    2003-01-01

    For the construction of an electron cyclotron resonance (ECR) charge breeder (CB) at KEK-JAERI radioactive nuclear beam facility, we have made a pilot charge breeding system consisting of two compact-sized ECR ion sources. In order to find the necessary conditions for an ECRCB with high efficiency, the charge breeding efficiency for Ar ions in nitrogen plasma has been measured and compared with the results from the simulation of the trajectories of the ions in the plasma. By explicitly taking into account the cumulative small angle scattering of charged ions as well as the confinement magnetic field of the pilot CB, the simulation predicts the stopping efficiency. This is defined as a probability that the injected ions are still within the plasma volume when their initial directional motions have become randomized. Incorporating the ionization efficiency for the ions, the overall breeding efficiency has been estimated. Finally, the characteristics of the ECRCB recently installed for tests at KEK is described.

  12. Design of the extraction system and beamline of the superconducting ECR ion source VENUS

    Energy Technology Data Exchange (ETDEWEB)

    Leitner, Matthaeus A.; Wutte, Daniela C.; Lyneis, Claude M.

    2001-05-07

    A new, very high magnetic field superconducting ECR ion source, VENUS, is under construction at the LBNL 88-Inch Cyclotron [1,2]. The paper describes the VENUS extraction system and discusses the ion beam formation in the strong axial magnetic field (3 T) of the ECR ion source. Emittance values as expected from theory, which assumes a uniform plasma density across the plasma outlet hole, are compared with actual measurements from the AECR-U ion source. Results indicate that highly charged heavier ions are concentrated on the source axis. They are extracted from an ''effective'' plasma outlet hole, whose smaller radius must be included in ion optics simulations.

  13. Plasma edge and plasma-wall interaction modelling: Lessons learned from metallic devices

    Directory of Open Access Journals (Sweden)

    S. Wiesen

    2017-08-01

    Full Text Available Robust power exhaust schemes employing impurity seeding are needed for target operational scenarios in present day tokamak devices with metallic plasma-facing components (PFCs. For an electricity-producing fusion power plant at power density Psep/R>15MW/m divertor detachment is a requirement for heat load mitigation. 2D plasma edge transport codes like the SOLPS code as well as plasma-wall interaction (PWI codes are key to disentangle relevant physical processes in power and particle exhaust. With increased quantitative credibility in such codes more realistic and physically sound estimates of the life-time expectations and performance of metallic PFCs can be accomplished for divertor conditions relevant for ITER and DEMO. An overview is given on the recent progress of plasma edge and PWI modelling activities for (carbon-free metallic devices, that include results from JET with the ITER-like wall, ASDEX Upgrade and Alcator C-mod. It is observed that metallic devices offer an opportunity to progress the understanding of underlying plasma physics processes in the edge. The validation of models can be substantially improved by eliminating carbon from the experiment as well as from the numerical system with reduced degrees of freedom as no chemical sputtering from amorphous carbon layers and no carbon or hydro-carbon transport are present. With the absence of carbon as the primary plasma impurity and given the fact that the physics of the PWI at metallic walls is less complex it is possible to isolate the crucial plasma physics processes relevant for particle and power exhaust. For a reliable 2D dissipative plasma exhaust model these are: cross-field drifts, complete kinetic neutral physics, geometry effects (including main-chamber, divertor and sub-divertor structures, SOL transport reflecting also the non-diffusive nature of anomalous transport, as well as transport within the pedestal region in case of significant edge impurity radiation

  14. Experimental investigation of vapor shielding effects induced by ELM-like pulsed plasma loads using the double plasma gun device

    Science.gov (United States)

    Sakuma, I.; Kikuchi, Y.; Kitagawa, Y.; Asai, Y.; Onishi, K.; Fukumoto, N.; Nagata, M.

    2015-08-01

    We have developed a unique experimental device of so-called double plasma gun, which consists of two magnetized coaxial plasma gun (MCPG) devices, in order to clarify effects of vapor shielding on material erosion due to transient events in magnetically confined fusion devices. Two ELM-like pulsed plasmas produced by the two MCPG devices were injected into a target chamber with a variable time difference. For generating ablated plasmas in front of a target material, an aluminum foil sample in the target chamber was exposed to a pulsed plasma produced by the 1st MCPG device. The 2nd pulsed plasma was produced with a time delay of 70 μs. It was found that a surface absorbed energy measured by a calorimeter was reduced to ∼66% of that without the Al foil sample. Thus, the reduction of the incoming plasma energy by the vapor shielding effect was successfully demonstrated in the present experiment.

  15. Experimental investigation of vapor shielding effects induced by ELM-like pulsed plasma loads using the double plasma gun device

    Energy Technology Data Exchange (ETDEWEB)

    Sakuma, I., E-mail: eu13z002@steng.u-hyogo.ac.jp; Kikuchi, Y.; Kitagawa, Y.; Asai, Y.; Onishi, K.; Fukumoto, N.; Nagata, M.

    2015-08-15

    We have developed a unique experimental device of so-called double plasma gun, which consists of two magnetized coaxial plasma gun (MCPG) devices, in order to clarify effects of vapor shielding on material erosion due to transient events in magnetically confined fusion devices. Two ELM-like pulsed plasmas produced by the two MCPG devices were injected into a target chamber with a variable time difference. For generating ablated plasmas in front of a target material, an aluminum foil sample in the target chamber was exposed to a pulsed plasma produced by the 1st MCPG device. The 2nd pulsed plasma was produced with a time delay of 70 μs. It was found that a surface absorbed energy measured by a calorimeter was reduced to ∼66% of that without the Al foil sample. Thus, the reduction of the incoming plasma energy by the vapor shielding effect was successfully demonstrated in the present experiment.

  16. Dusty Plasma Experimental (DPEx) device for complex plasma experiments with flow

    CERN Document Server

    Jaiswal, S; Sen, A

    2015-01-01

    A versatile table-top dusty plasma experimental device (DPEx) to study flow induced excitations of linear and nonlinear waves/structures in a complex plasma is presented. In this $\\Pi$-shaped apparatus a DC glow discharge plasma is produced between a disc shaped anode and a grounded long cathode tray by applying a high voltage DC in the background of a neutral gas and subsequently a dusty plasma is created by introducing micron sized dust particles that get charged and levitated in the sheath region. A flow of the dust particles is induced in a controlled manner by adjusting the pumping speed and the gas flow rate into the device. A full characterisation of the plasma, using Langmuir and emissive probe data, and that of the dusty plasma using particle tracking data with the help of an idl based (super) Particle Identification and Tracking (sPIT) code is reported. Experimental results on the variation of the dust flow velocity as a function of the neutral pressure and the gas flow rate are given. The potential...

  17. Status of ECR ion sources at JAERI

    CERN Document Server

    Yokota, W; Nara, T; Ishi, Y; Arakawa, K; Ohkoshi, K

    1999-01-01

    At the Takasaki site of Japan Atomic Energy Research Institute, four ECR ion sources were purchased or developed so far. This paper will report their performance, modification and status. The outlines for each source are as follows; 1. OCTOPUS purchased from IBA s.a. has been in use with a cyclotron since 1990. The gas feed system was modified to change gas species within 10 minutes to avoid impurity ions in the cocktail beam acceleration technique of the cyclotron. 2. ECR-18 with 18-GHz microwave has a solenoid coil between a pair of mirror coils to change mirror ratio in a wide range. A bump between mirror peaks in the original axial field distribution was removed by halving the solenoid length. The performance in generating high charge state ions was significantly improved as a result. 3. HYPERNANOGAN was purchased from PANTECHNIK s.a. and installed in the cyclotron system this year. Test operation was successfully made with generation of Ar, Pb and Ta ions. 4. MINI ECR is a full permanent magnet source wi...

  18. Paper-based microfluidic devices by plasma treatment.

    Science.gov (United States)

    Li, Xu; Tian, Junfei; Nguyen, Thanh; Shen, Wei

    2008-12-01

    Paper-based microfluidic patterns have been demonstrated in recent literature to have a significant potential in developing low-cost analytical devices for telemedicine and general health monitoring. This study reports a new method for making microfluidic patterns on a paper surface using plasma treatment. Paper was first hydrophobized and then treated using plasma in conjunction with a mask. This formed well defined hydrophilic channels on the paper. Paper-based microfluidic systems produced in this way retained the flexibility of paper and a variety of patterns could be formed. A major advantage of this system is that simple functional elements such as switches and filters can be built into the patterns. Examples of these elements are given in this study.

  19. Versatile and Rapid Plasma Heating Device for Steel and Aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, G.S.

    2006-03-14

    The main objective of the research was to enhance steel and aluminum manufacturing with the development of a new plasma RPD device. During the project (1) plasma devices were manufactured (2) testing for the two metals were carried out and (3) market development strategies were explored. Bayzi Corporation has invented a Rapid Plasma Device (RPD) which produces plasma, comprising of a mixture of ionized gas and free electrons. The ions, when they hit a conducting surface, deposit heat in addition to the convective heat. Two generic models called the RPD-Al and RPD-S have been developed for the aluminum market and the steel market. Aluminum melting rates increased to as high as 12.7 g/s compared to 3 g/s of the current industrial practice. The RPD melting furnace operated at higher energy efficiency of 65% unlike most industrial processes operating in the range of 13 to 50%. The RPD aluminum melting furnace produced environment friendly cleaner melts with less than 1% dross. Dross is the residue in the furnace after the melt is poured out. Cast ingots were extremely clean and shining. Current practices produce dross in the range of 3 to 12%. The RPD furnace uses very low power ~0.2 kWh/Lb to melt aluminum. RPDs operate in one atmosphere using ambient air to produce plasma while the conventional systems use expensive gases like argon, or helium in air-tight chambers. RPDs are easy to operate and do not need intensive capital investment. Narrow beam, as well as wide area plasma have been developed for different applications. An RPD was developed for thermal treatments of steels. Two different applications have been pursued. Industrial air hardening steel knife edges were subjected to plasma beam hardening. Hardness, as measured, indicated uniform distribution without any distortion. The biggest advantage with this method is that the whole part need not be heated in a furnace which will lead to oxidation and distortion. No conventional process will offer localized

  20. MHD instabilities and their effects on plasma confinement in the large helical device plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Toi, K.; Ohdachi, S. [National Inst. for Fusion Science, Toki, Gifu (Japan); Yamamoto, S. [Nagoya Univ., Dept. of Energy Engineering and Science, Nagoya, Aichi (JP)] [and others

    2002-11-01

    Characteristics of MHD instabilities and their impacts on plasma confinement are studied in current free plasmas of the Large Helical Device (LHD). Spontaneous L-H transition is often observed in high beta plasmas in the range of 2% averaged beta at low toroidal field (B{sub t} {<=} 0.6T). The stored energy rapidly rises with the transition, but quickly saturates due to the growth of m=2/n=3 and m=2/n=2 modes (m and n: poloidal and toroidal mode numbers) excited in the plasma edge region. Even in low beta plasmas, ELM activities are sometimes induced in high performance plasmas with a steep edge pressure gradient, and transiently reduce the stored energy by about 10%. Energetic ion driven MHD modes such as Alfven eigenmodes are studied in the very wide range of characteristic parameters: the averaged beta of energetic ions <{beta}{sub b//}> up to 5% and the ratio of energetic ion velocity to the Alfven velocity V{sub b//}/V{sub A} up to 2.5. In addition to the observation of toroidicity induced Alfven eigenmodes (TAEs), coherent magnetic fluctuations of helicity induced Alfven eigenmodes (HAEs) have been observed for the first time in NBI heated plasmas. The transition of the TAE to the global Alfven eigenmode (GAE) is also observed in a discharge with temporal evolution of the rotational transform profile, having a similarity to the phenomenon in a reversed shear tokamak. At low magnetic field, bursting TAEs transiently induce a significant loss of energetic ions, but lead to the transient improvement of bulk plasma confinement in the plasma central region. (author)

  1. MHD instabilities and their effects on plasma confinement in the large helical device plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Toi, K.; Ohdachi, S. [National Inst. for Fusion Science, Toki, Gifu (Japan); Yamamoto, S. [Nagoya Univ., Dept. of Energy Engineering and Science, Nagoya, Aichi (JP)] [and others

    2002-10-01

    Characteristics of MHD instabilities and their impacts on plasma confinement are studied in current free plasmas of the Large Helical Device (LHD). Spontaneous L-H transition is often observed in high beta plasmas in the range of 2% averaged beta at low toroidal field (B{sub t} {<=} 0.6 T). The stored energy rapidly rises by the transition, but quickly saturates by the growth of m=2/n=3 and m=2/n=2 modes (m and n: poloidal and toroidal mode numbers) excited in the plasma edge region. Even low beta plasmas, ELM like activities are sometimes induced in high performance plasmas with high edge pressure pedestal, and transiently reduce the stored energy by about 10%. Energetic ion driven MHD modes such as Alfven eigenmodes are studied in the very wide parameter range of the averaged beta of energetic ions <{beta}{sub b} sub (parallel)> up to 5% and the ratio of energetic ion velocity to the Alfven velocity V{sub b} sub (parallel)/V{sub A} up to 2.5. In addition to the observation of toroidicity induced Alfven eigenmodes (TAEs), coherent magnetic fluctuations of helicity induced Alfven eigenmodes (HAEs) have been observed for the first time in NBI heated plasmas. Transition of TAE to global Alfven eigenmode (GAE) is also observed in a discharge with temporal evolution of the rotational transform profile, having a similarity to the phenomenon in a reversed shear tokamak. At the low magnetic field, bursting TAEs enhance energetic ion loss transiently, but lead to the transient improvement of bulk plasma confinement in the plasma central region. (author)

  2. Defect generation in electronic devices under plasma exposure: Plasma-induced damage

    Science.gov (United States)

    Eriguchi, Koji

    2017-06-01

    The increasing demand for higher performance of ULSI circuits requires aggressive shrinkage of device feature sizes in accordance with Moore’s law. Plasma processing plays an important role in achieving fine patterns with anisotropic features in metal-oxide-semiconductor field-effect transistors (MOSFETs). This article comprehensively addresses the negative aspect of plasma processing — plasma-induced damage (PID). PID naturally not only modifies the surface morphology of materials but also degrades the performance and reliability of MOSFETs as a result of defect generation in the materials. Three key mechanisms of PID, i.e., physical, electrical, and photon-irradiation interactions, are overviewed in terms of modeling, characterization techniques, and experimental evidence reported so far. In addition, some of the emerging topics — control of parameter variability in ULSI circuits caused by PID and recovery of PID — are discussed as future perspectives.

  3. Investigation of a large power water-cooled microwave resonance window for application with the ECR ion source

    Science.gov (United States)

    Guo, Guo; Guo, Junwei; Niu, Xinjian; Liu, Yinghui; Wang, Hui; Wei, Yanyu

    2017-06-01

    A large power water-cooled microwave resonance window used for the electron cyclotron resonance (ECR) ion source is investigated in this paper. The microwave characteristic simulation, thermal analysis, and structure design are deeply and successively carried out before fabrication. After the machining and welding of the components, the window is cold and hot tested. The application results demonstrate that when the input power is 2000 W, the reflected power is only 5 W. The vacuum is below 10-10 Pa, and the high power microwave operation can last 30 h continuously and reliably, which indicates that the design and assembling can achieve the high efficiency of the microwave transmission. Finally, the performance of the ECR ion source is enhanced by the improvement of the injected microwave power to the ECR plasma.

  4. ECR ion source for high current linac

    CERN Document Server

    Cui Bao Qun; Jiang Wei; LiLiQiang; WangRongWen

    2002-01-01

    An intense ECR ion source for ADS (accelerator driven sub-critical system) is described. Two configurations of the source has been developed and tested. 100 mA hydrogen beam has been extracted from the ion source at 30 keV, the proton ratio is greater than 85%, estimated emittance is 0.11 pi mm centre dot mrad, the maximum extracted beam density is 340 mA/cm sup 2 . A 100 hours reliability test of the source is also described

  5. Characterization of bismuth nanospheres deposited by plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, M., E-mail: cscientific2@aec.org.sy [IBA Laboratory, Chemistry Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic); Al-Hawat, Sh.; Akel, M. [Physics Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic); Mrad, O. [Chemistry Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic)

    2015-02-14

    A new method for producing thin layer of bismuth nanospheres based on the use of low energy plasma focus device is demonstrated. Various techniques such as scanning electron microscopy, Rutherford backscattering spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy have been used to characterize the morphology and the composition of the nanospheres. Experimental parameters may be adjusted to favour the formation of bismuth nanospheres instead of microspheres. Therefore, the formation of large surface of homogeneous layer of bismuth nanospheres with sizes of below 100 nm can be obtained. The natural snowball phenomenon is observed to be reproduced in nanoscale where spheres roll over the small nanospheres and grow up to bigger sizes that can reach micro dimensions. The comet-like structure, a reverse phenomenon to snowball is also observed.

  6. 6.4 GHz ECR ion source at VECC

    Indian Academy of Sciences (India)

    The 6.4 GHz ECR ion source that was indigenously developed a few years ago has been operating continuously for injecting oxygen and neon beams to the cyclotron since 1997. VEC-ECR is a single stage high magnetic field ion source provided with a negatively biased electron repeller placed on the axis, near the ...

  7. ECR ion source based low energy ion beam facility

    Indian Academy of Sciences (India)

    A nanogan type of ECR source based on a fully permanent magnet design was chosen for this purpose [3]. The ECR ion source along with all its peripheral electron- ics and vacuum components placed on a 200 kV high voltage platform provides multiply charged positive ions in a widely varying energy range from a few ...

  8. 24 GHz microwave mode converter optimized for superconducting ECR ion source SECRAL

    Energy Technology Data Exchange (ETDEWEB)

    Guo, J. W., E-mail: jwguo@impcas.ac.cn [Institute of Modern Physics (IMP), Chinese Academy of Science, Lanzhou 730000 (China); University of Chinese Academy of Sciences, Beijing 100039 (China); Sun, L.; Zhang, X. Z.; Lu, W.; Zhang, W. H.; Feng, Y. C.; Zhao, H. W. [Institute of Modern Physics (IMP), Chinese Academy of Science, Lanzhou 730000 (China); Niu, X. J. [University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2016-02-15

    Over-sized round waveguide with a diameter about Ø33.0 mm excited in the TE{sub 01} mode has been widely adopted for microwave transmission and coupling to the ECR (Electron Cyclotron Resonance) plasma with the superconducting ECR ion sources operating at 24 or 28 GHz, such as SECRAL and VENUS. In order to study the impact of different microwave modes on ECRH (Electron Cyclotron Resonance Heating) efficiency and especially the production of highly charged ions, a set of compact and efficient TE{sub 01}-HE{sub 11} mode conversion and coupling system applicable to 24 GHz SECRAL whose overall length is 330 mm has been designed, fabricated and tested. Good agreements between off-line tests and calculation results have been achieved, which indicates the TE{sub 01}-HE{sub 11} converter meets the application design. The detailed results of the optimized coupling system will be presented in the paper.

  9. Parallel collisionless-shock experiments at the Large Plasma Device

    Science.gov (United States)

    Weidl, Martin; Heuer, Peter; Bondarenko, Anton; Schaeffer, Derek; Winske, Dan; Constantin, Carmen; Jenko, Frank; Niemann, Christoph

    2017-04-01

    Previous research on parallel collisionless shocks, which constitute an important part of the Earth's bow shock region, has been limited to satellite measurements and simulations. However, whether and how these collisionless shocks form depends on a wide range of parameters and scales, some of which can be established and measured more easily in a laboratory experiment. Using a kJ-class laser, an ongoing experimental campaign at the Large Plasma Device (LAPD) at UCLA in Los Angeles is expected to produce the first laboratory measurements of the formation of a parallel collisionless shock. We present hybrid kinetic/MHD simulations which show how ion-beam instabilities in the background plasma can be driven by ablating carbon ions from a polyethylene target, causing non-linear density oscillations which eventually develop into a propagating shock front. The free-streaming carbon ions can excite both the resonant right-hand instability and the non-resonant firehose mode, the latter of which has also received a lot of attention among astrophysicists as Bell's instability. We present measurements from a first trial experiment at LAPD, in which we have identified these instabilities, and discuss their respective roles for future shock formation and the basic microphysical processes which drive them.

  10. Hard X-ray sources from miniature plasma focus devices

    Energy Technology Data Exchange (ETDEWEB)

    Raspa, V. [Buenos Aires Univ., PLADEMA, CONICET and INFIP (Argentina); Silva, P.; Moreno, J.; Zambra, M.; Soto, L. [Comision Chilena de Energia Nuclear, Santiago (Chile)

    2004-07-01

    As first stage of a program to design a repetitive pulsed radiation generator for industrial applications, two miniature plasma foci have been designed and constructed at the Chilean commission of nuclear energy. The devices operate at an energy level of the order of tens of joules (PF-50 J, 160 nF capacitor bank, 20-35 kV, 32-100 J, {approx} 150 ns time to peak current) and hundred of joules (PF-400 J, 880 nF, 20-35 kV, 176-539 J, {approx} 300 ns time to peak current). Hard X-rays are being studied in these devices operating with hydrogen. Images of metallic plates with different thickness were obtained on commercial radiographic film, Agfa Curix ST-G2, in order to characterize the energy of the hard X-ray outside of the discharge chamber of PF-400 J. An effective energy of the order of 90 keV was measured under those conditions. X ray images of different metallic objects also have been obtained. (authors)

  11. Interaction of powerful hot plasma and fast ion streams with materials in dense plasma focus devices

    Energy Technology Data Exchange (ETDEWEB)

    Chernyshova, M., E-mail: maryna.chernyshova@ipplm.pl [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Gribkov, V.A. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Institution of Russian Academy of Sciences A.A. Baikov Institute of Metallurgy and Material Science RAS, Moscow (Russian Federation); Kowalska-Strzeciwilk, E.; Kubkowska, M.; Miklaszewski, R.; Paduch, M.; Pisarczyk, T.; Zielinska, E. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Demina, E.V.; Pimenov, V.N.; Maslyaev, S.A. [Institution of Russian Academy of Sciences A.A. Baikov Institute of Metallurgy and Material Science RAS, Moscow (Russian Federation); Bondarenko, G.G. [National Research University Higher School of Economics (HSE), Moscow (Russian Federation); Vilemova, M.; Matejicek, J. [Institute of Plasma Physics of the CAS, Prague (Czech Republic)

    2016-12-15

    Highlights: • Materials perspective for use in mainstream nuclear fusion facilities were studied. • Powerful streams of hot plasma and fast ions were used to induce irradiation. • High temporal, spatial, angular and spectral resolution available in experiments. • Results of irradiation were investigated by number of analysis techniques. - Abstract: A process of irradiating and ablating solid-state targets with hot plasma and fast ion streams in two Dense Plasma Focus (DPF) devices – PF-6 and PF-1000 was examined by applying a number of diagnostics of nanosecond time resolution. Materials perspective for use in chambers of the mainstream nuclear fusion facilities (mainly with inertial plasma confinement like NIF and Z-machine), intended both for the first wall and for constructions, have been irradiated in these simulators. Optical microscopy, SEM, Atomic Emission Spectroscopy, images in secondary electrons and in characteristic X-ray luminescence of different elements, and X-ray elemental analysis, gave results on damageability for a number of materials including low-activated ferritic and austenitic stainless steels, β-alloy of Ti, as well as two types of W and a composite on its base. With an increase of the number of shots irradiating the surface, its morphology changes from weakly pronounced wave-like structures or ridges to strongly developed ones. At later stages, due to the action of the secondary plasma produced near the target materials they melted, yielding both blisters and a fracturing pattern: first along the grain and then “in-between” the grains creating an intergranular net of microcracks. At the highest values of power flux densities multiple bubbles appeared. Furthermore, in this last case the cracks were developed because of microstresses at the solidification of melt. Presence of deuterium within the irradiated ferritic steel surface nanolayers is explained by capture of deuterons in lattice defects of the types of impurity atoms

  12. The plasma device for the high-heat plasma testing of refractory metals and inventing of new highly porous materials

    Science.gov (United States)

    Budaev, V. P.; Fedorovich, S. D.; Martynenko, Yu V.; Lukashevsky, M. V.; Gubkin, M. K.; Lazukin, A. V.; Karpov, A. V.; Shestakov, E. A.

    2017-11-01

    A unique plasma device has been constructed at the NRU “MPEI” for the study of plasma-surface interaction and the high-heat plasma testing of refractory metals, such as tungsten, molybdenum, steel and other plasma facing materials used in fusion reactor including the ITER. This plasma device is a multi-cusp linear stationary plasma confinement system. It has power-saving characteristics as well as compactness due to the employment of the 8-pole multicusp magnetic field configuration instead of a strong axial magnetic field. Experiments are planned to develop a novel technology for highly porous surface structure of the refractory metal with a pore size and nanofibers of 50 nanometers including tungsten “fuzz”.

  13. The Dynamics of an Isolated Plasma Filament at the Edge of a Toroidal Device, Rev. 1

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D D

    2006-09-28

    The dynamics of an isolated plasma filament (an isolated blob) in the far scrape-off layer (SOL) of a toroidal device is described, with a proper averaging of the geometrical parameters as well as plasma parameters along the filament. The analysis is limited to the magnetohydrodynamic description. The effects of the anchored ends and finite plasma resistivity are also discussed.

  14. Oral bacterial inactivation using a novel low-temperature atmospheric-pressure plasma device

    Directory of Open Access Journals (Sweden)

    Ya-Ting Chang

    2016-03-01

    Conclusion: The novel low-temperature atmospheric-pressure device was capable of achieving effective sterilization of E. faecalis within a 2-minute interval. Further studies are needed to validate complete inactivation, refine the laboratory-made low-temperature plasma device, and develop a new plasma-jet device, which will be superior to traditional sterilization methods and can be used in root canal environment. This novel sterilization method can also be used as a clinical reference tool.

  15. Thrust Stand Measurements of a Conical Pulsed Inductive Plasma Thruster

    Science.gov (United States)

    Hallock, Ashley K.; Polzin, Kurt A.; Emsellem, Gregory D.

    2012-01-01

    Pulsed inductive plasma thrusters [1-3] are spacecraft propulsion devices in which electrical energy is capacitively stored and then discharged through an inductive coil. The thruster is electrodeless, with a time-varying current in the coil interacting with a plasma covering the face of the coil to induce a plasma current. Propellant is accelerated and expelled at a high exhaust velocity (O(10-100 km/s)) by the Lorentz body force arising from the interaction of the magnetic field and the induced plasma current. While this class of thruster mitigates the life-limiting issues associated with electrode erosion, pulsed inductive plasma thrusters can su er from both high pulse energy requirements imposed by the voltage demands of inductive propellant ionization, and low propellant utilization efficiencies. The Microwave Assisted Discharge Inductive Plasma Accelerator (MAD-IPA)[4], shown in Fig. 1 is a pulsed inductive plasma thruster that is able to operate at lower pulse energies by partially ionizing propellant with an electron cyclotron resonance (ECR) discharge inside a conical inductive coil whose geometry serves to potentially increase propellant and plasma plume containment relative to at coil geometries. The ECR plasma is created with the use of permanent mag- nets arranged to produce a thin resonance region along the inner surface of the coil, restricting plasma formation and, in turn, current sheet formation to areas of high magnetic coupling to the driving coil.

  16. Construction of the superconducting ECR ion source Venus

    Energy Technology Data Exchange (ETDEWEB)

    Leitner, M.A.; Lyneis, C.M.; Wutte, D.C.; Taylor, C.E.; Abbott, S.R. [Lawrence Berkeley National Lab., CA (United States)

    2001-07-01

    A new, very high magnetic field superconducting ECR ion source, VENUS, is under development at the LBNL 88-inch cyclotron. It will boost the maximum energies and intensities for heavy ions from the cyclotron particularly for ions with mass greater than 60. It will also serve as R and D ion source for the proposed rare isotope accelerator (RIA) project in the US, which requires up to 10 p{mu}A of U{sup 30+}. The superconducting magnet structure consists of three solenoids and six racetrack coils with iron poles forming the sextupole. The coils are designed to generate a 4 T axial mirror field at injection and 3 T at extraction and a radial sextupole field of 2.4 T at the plasma chamber wall. Test results of the magnet coils, which exceeded design requirements with minimum training, are presented. The magnet assembly with its cryostat will be enclosed by an iron shield and therefore must be designed to withstand any possible forces between coils and iron, which can be as high as 3.4.10{sup 5} N (35,000 kgf). The low energy beam transport line (LEBT) and mass analyzing system of the ion source is designed to transport a proton-equivalent current of 25 mA at 20 kV extraction voltage. The design of the ion source and LEBT will be discussed. (orig.)

  17. Experimental system of ejected electron spectroscopy with ECR ion source

    Energy Technology Data Exchange (ETDEWEB)

    Kitazawa, Sin-iti [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1995-09-01

    The experiment of analyzing energy spectrum of electrons ejected from multiple electron capture process on ion-atom collision is carried out using ECR (Electron Cyclotron Resonance) ion source. An old collision system using gas atoms as target and a new system using vapour atoms are developed. In this report, the developments and exploitations of the experimental systems for the ejected electron spectroscopy with ECR Ion source are presented. (author).

  18. Development of a compact thermal lithium atom beam source for measurements of electron velocity distribution function anisotropy in electron cyclotron resonance plasmas.

    Science.gov (United States)

    Nishioka, T; Shikama, T; Nagamizo, S; Fujii, K; Zushi, H; Uchida, M; Iwamae, A; Tanaka, H; Maekawa, T; Hasuo, M

    2013-07-01

    The anisotropy of the electron velocity distribution function (EVDF) in plasmas can be deduced from the polarization of emissions induced by anisotropic electron-impact excitation. In this paper, we develop a compact thermal lithium atom beam source for spatially resolved measurements of the EVDF anisotropy in electron cyclotron resonance (ECR) plasmas. The beam system is designed such that the ejected beam has a slab shape, and the beam direction is variable. The divergence and flux of the beam are evaluated by experiments and calculations. The developed beam system is installed in an ECR plasma device with a cusp magnetic field, and the LiI 2s-2p emission (670.8 nm) is observed in low-pressure helium plasma. The two-dimensional distributions of the degree and direction of the polarization in the LiI emission are measured by a polarization imaging system. The evaluated polarization distribution suggests the spatial variation of the EVDF anisotropy.

  19. Study of Amorphous Carbon Nitride Films Aiming at White Light Emitting Devices

    Science.gov (United States)

    Iwano, Yuta; Kittaka, Toshiaki; Tabuchi, Hidekazu; Soukawa, Masaya; Kunitsugu, Shinsuke; Takarabe, Kenichi; Itoh, Kunio

    2008-10-01

    The possibility for white light emitting devices using carbon nitride (CNx) thin films has been studied. Microwave electron cyclotron resonance (ECR)-plasma chemical vapor deposition (CVD) and RF-sputtering apparatuses have been used for the formation of CNx thin films. In both cases, CH4 was used as the source or sub-source of carbon in order to investigate the effect of hydrogenated carbon nitride for luminescence. The cathodoluminescence (CL) measurement of the film grown by ECR-plasma CVD method showed three peaks of red, green, and blue (R/G/B). The photoluminescence (PL) measurement of the film grown by RF-sputtering also showed the red peak, which could not be observed in the film without hydrogen. Together with the X-ray photoelectron spectroscopy (XPS) analysis data, we concluded that the red peak originates from the level relating to H atom and blue peak from C-N bonds.

  20. Electron-cyclotron plasma startup in the GDT experiment

    CERN Document Server

    Yakovlev, D V; Gospodchikov, E D; Solomakhin, A L; Savkin, V Ya; Bagryansky, P A

    2016-01-01

    The paper reports on a new plasma startup scenario in the Gas Dynamic Trap (GDT) magnetic mirror device. The primary 5 MW neutral beam injection (NBI) plasma heating system fires into a sufficiently dense plasma target ("seed plasma"), which is commonly supplied by an arc plasma generator. In the reported experiments, a different approach to seed plasma generation is explored. One of the channels of the electron cyclotron resonance (ECR) heating system is used to ionize the neutral gas and build up the density of plasma to a level suitable for NBI capture. After a short transition (about 1 ms) the discharge becomes essentially similar to a standard one initiated by the plasma gun. The paper presents the discharge scenario and experimental data on the seed plasma evolution during ECR heating, along with the dependencies on incident microwave power, magnetic configuration and pressure of a neutral gas. The characteristics of consequent high-power NBI discharge are studied and differences to the conventional sce...

  1. Electron cyclotron plasma startup in the GDT experiment

    Science.gov (United States)

    Yakovlev, D. V.; Shalashov, A. G.; Gospodchikov, E. D.; Solomakhin, A. L.; Savkin, V. Ya.; Bagryansky, P. A.

    2017-01-01

    We report on a new plasma startup scenario in the gas dynamic trap (GDT) magnetic mirror device. The primary 5 MW neutral beam injection (NBI) plasma heating system fires into a sufficiently dense plasma target (‘seed plasma’), which is commonly supplied by an arc plasma generator. In the reported experiments, a different approach to seed plasma generation is explored. One of the channels of the electron cyclotron resonance (ECR) heating system is used to ionize the neutral gas and build up the density of plasma to a level suitable for NBI capture. After a short transition of approximately 1 ms the discharge becomes essentially similar to a standard one initiated by the plasma gun. This paper presents the discharge scenario and experimental data on the seed plasma evolution during ECRH, along with the dependencies on incident microwave power, magnetic configuration and pressure of a neutral gas. The characteristics of the consequent high-power NBI discharge are studied and differences from the conventional scenario are discussed. A theoretical model describing the ECR breakdown and the seed plasma accumulation in a large-scale mirror trap is developed on the basis of the GDT experiment.

  2. DEVICE FOR INVESTIGATION OF MAGNETRON AND PULSED-LASER PLASMA

    Directory of Open Access Journals (Sweden)

    A. P. Burmakov

    2012-01-01

    Full Text Available Various modifications of complex pulsed laser and magnetron deposition thin-film structures unit are presented. They include joint and separate variants of layer deposition. Unit realizes the plasma parameters control and enhances the possibility of laser-plasma and magnetron methods of coatings deposition.

  3. A New 14 GHz ECR Ion Source for the Heavy Ion Accelerator Facility ATLAS

    Science.gov (United States)

    Schlapp, M.; Vondrasek, R. C.; Szczech, J.; Billquist, P. J.; Pardo, R. C.; Xie, Z. Q.; Harkewicz, R.

    1997-05-01

    A new 14 GHz ECRIS has been designed and built over the last two years. The source design incorporates the latest results from ECR developments to produce intense beams of highly charged ions, i.e. an improved magnetic electron confinement. The aluminum plasma chamber and extraction electrode as well as a biased disk on axis at the microwave injection side donate additional electrons to the plasma, making use of the large secondary electron yield from aluminum oxide. The source will be capable of ECR plasma heating using two different frequencies simultaneously to increase the electron energy gain for the production of high charge states. To be able to deliver usable intensities of the heaviest ion beams the design will also allow axial access for metal evaporation ovens and solid material samples. The main design goal is to produce several eμA of at least ^238U^34+ in order to accelerate the beam to coulomb-barrier energies without further stripping. That should also significantly improve the beam quality over beams requiring stripping for acceleration. This work was supported by US D.O.E. Nuclear Physics Division under contract W-31-109-ENG-38.

  4. Investigation on physicochemical properties of plasma-activated water for the application of medical device sterilization

    Science.gov (United States)

    Abuzairi, Tomy; Ramadhanty, Savira; Puspohadiningrum, Dini Fithriaty; Ratnasari, Anita; Poespawati, Nji Raden; Purnamaningsih, Retno Wigajatri

    2018-02-01

    Plasma activated water (PAW) is a new approach to bacterial inactivation while ensuring safety and maintaining the properties of the material sterilized. Reported research imply that PAW has been effective for inactivation of bacteria. In this paper, plasma treatment using atmospheric pressure plasma was demonstrated. Physicochemical properties such as pH, temperature, ORP, and nitrite concentration were assessed. The results suggest that plasma treatment causes acidification on water and generate reactive species, creating an environment suitable for killing bacteria. Therefore, plasma activated water is an assuring method for medical devices sterilization.

  5. Chlorine-based plasma etching of GaN

    Energy Technology Data Exchange (ETDEWEB)

    Shul, R.J.; Briggs, R.D. [Sandia National Labs., Albuquerque, NM (United States); Pearton, S.J.; Vartuli, C.B.; Abernathy, C.R.; Lee, J.W. [Univ. of Florida, Gainesville, FL (United States). Dept. of Materials Science and Engineering; Constantine, C.; Baratt, C. [Plasma-Therm, Inc., Saint Petersburg, FL (United States)

    1997-02-01

    The wide band gap group-III nitride materials continue to generate interest in the semiconductor community with the fabrication of green, blue, and ultraviolet light emitting diodes (LEDs), blue lasers, and high temperature transistors. Realization of more advanced devices requires pattern transfer processes which are well controlled, smooth, highly anisotropic and have etch rates exceeding 0.5 {micro}m/min. The utilization of high-density chlorine-based plasmas including electron cyclotron resonance (ECR) and inductively coupled plasma (ICP) systems has resulted in improved GaN etch quality over more conventional reactive ion etch (RIE) systems.

  6. Development and experimental study of large size composite plasma immersion ion implantation device

    Science.gov (United States)

    Falun, SONG; Fei, LI; Mingdong, ZHU; Langping, WANG; Beizhen, ZHANG; Haitao, GONG; Yanqing, GAN; Xiao, JIN

    2018-01-01

    Plasma immersion ion implantation (PIII) overcomes the direct exposure limit of traditional beam-line ion implantation, and is suitable for the treatment of complex work-piece with large size. PIII technology is often used for surface modification of metal, plastics and ceramics. Based on the requirement of surface modification of large size insulating material, a composite full-directional PIII device based on RF plasma source and metal plasma source is developed in this paper. This device can not only realize gas ion implantation, but also can realize metal ion implantation, and can also realize gas ion mixing with metal ions injection. This device has two metal plasma sources and each metal source contains three cathodes. Under the condition of keeping the vacuum unchanged, the cathode can be switched freely. The volume of the vacuum chamber is about 0.94 m3, and maximum vacuum degree is about 5 × 10‑4 Pa. The density of RF plasma in homogeneous region is about 109 cm‑3, and plasma density in the ion implantation region is about 1010 cm‑3. This device can be used for large-size sample material PIII treatment, the maximum size of the sample diameter up to 400 mm. The experimental results show that the plasma discharge in the device is stable and can run for a long time. It is suitable for surface treatment of insulating materials.

  7. Electron cyclotron resonance heating in a short cylindrical plasma ...

    Indian Academy of Sciences (India)

    Electron cyclotron resonance (ECR) plasma is produced and studied in a small cylindrical system. Microwave power is delivered by a CW magnetron at 2.45 GHz in TE10 mode and launched radially to have extraordinary (X) wave in plasma. The axial magnetic field required for ECR in the system is such that the first two ...

  8. Understanding plasma facing surfaces in magnetic fusion devices

    Science.gov (United States)

    Skinner, C. H.; Capece, A. M.; Koel, B. E.; Roszell, J. P.

    2013-09-01

    The plasma-material interface is recognized to be the most critical challenge in the realization of fusion energy. Liquid metals offer a self-healing, renewable interface that bypasses present issues with solid, neutron-damaged materials such as tungsten. Lithium in particular has dramatically improved plasma performance in many tokamaks through a reduction of hydrogen recycling. However the detailed chemical composition and properties of the top few nm that interact with the plasma are often obscure. Surface analysis has proven to be a key tool in semiconductor processing and a new laboratory has been established at PPPL to apply surface science techniques to plasma facing materials. We have shown that lithiated PFC surfaces in tokamaks will likely be oxidized during the intershot interval. Present work is focused on deuterium uptake of solid and liquid metals for plasma density control and sub-micron scale wetting of liquid metals on their substrates. The long-term goal is to provide a material database for designing liquid metal plasma facing components for tokamaks such as National Spherical Torus Experiment-Upgrade (NSTX-U) and Fusion Nuclear Science Facility-ST (FNSF-ST). Support was provided through DOE-PPPL Contract Number is DE-AC02-09CH11466.

  9. Recent Developments for ECR Ion Sources at HIMAC

    CERN Document Server

    Kitagawa, A; Sekiguchi, M; Yamada, S; Okada, T; Yamamoto, M; Biri, S; Uno, K

    1999-01-01

    Two ECR ion sources are installed for the Heavy Ion Medical Accelerator in Chiba (HIMAC) at the National Institute of Radiological Sciences (NIRS). One of them, the NIRS-ECR, is a 10GHz ECR ion source, and is mainly operated to produce C4+ ions for the daily clinical treatment. The other source, the NIRS-HEC, is an 18GHz ECR ion source, and is expected to produce heavier ion species. In order to realize the uniform ion-density distribution at the extraction aperture for the higher beam intensity, the radial magnetic field given by the permanent sextupole magnet has been optimized. In the case of the optimized magnetic configuration of the NIRS-HEC, the extracted intensities of Ar8+ and Ar9+ ions increased from 250 and 150 up to 800 and 400 electric micro A, respectively. An optimized sextupole magnet for the NIRS-ECR is under construction. Other developments for increasing the beam intensity and extension of producible ion species are now in progress. An aluminum chamber, which is exchanged for the old copper...

  10. Platelet-rich plasma: updating of extraction devices

    Directory of Open Access Journals (Sweden)

    Raquel Moreno

    2016-12-01

    Full Text Available Propose: To describe PRP extraction devices, through a review of kits available in Spain, taking into account AEMPS and SEFH working groups (GPS, Farmacotecnia, Hemoderivados groups contributions. Methods: Three independent searches about PRP extraction devices were carried out. Device suppliers were contacted and an individually meeting was called with each one. Characteristics of each device was reviewed by virtual demonstration. A kits comparison chart was made with all the information acquired. Kits were classified as Closed-Technique and Opened- Technique in accordance with the AEMPS technical committee report. Results: Ten devices were found: ACP®; Angel®, Cascade®, Endoret ®, GPS®, Magellan®, Minos®, Ortho-pras®, Smart-prepr® and Tricell®. However, we could found out the mechanism in detail of seven of them. Information about Cascade®, Magellan ® and Smart-prepr® kits was not enough. Conclusion: The review provided the main PRP extraction devices available with CE marking and its distinguishing characteristics, however, it is crucial to pay attention to PRP extraction procedure and administration, to guarantee the final product quality. Pharmacy Department must get involved in the device selections due to the close link with the manufactured drug quality. Working together with the AEMPS will contribute to defining extraction procedure specifically.

  11. Characterization of an oxygen plasma process for cleaning packaged semiconductor devices. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Adams, B.E.

    1996-11-01

    The purpose of this research was to experimentally determine the operating {open_quotes}window{close_quotes} for an oxygen plasma cleaning process to be used on microelectronics components just prior to wire bonding. The process was being developed to replace one that used vapor degreasing with trichlorotrifluoroethane, an ozone-depleting substance. A Box-Behnken experimental design was used to generate data from which the oxygen plasma cleaning process could be characterized. Auger electron spectrophotometry was used to measure the contamination thickness on the dice after cleaning. An empirical equation correlating the contamination thickness on the die surface with the operating parameters of the plasma system was developed from the collected Auger data, and optimum settings for cleaning semiconductor devices were determined. Devices were also tested for undesirable changes in electrical parameters resulting from cleaning in the plasma system. An increase in leakage current occurred for bipolar transistors and diodes after exposure to the oxygen plasma. Although an increase in leakage current occurred, each device`s parameter remained well below the acceptable specification limit. Based upon the experimental results, the optimum settings for the plasma cleaning process were determined to be 200 watts of power applied for five minutes in an enclosure maintained at 0.7 torr. At these settings, all measurable contamination was removed without compromising the reliability of the devices.

  12. Transverse coupling property of beam from ECR ion sources.

    Science.gov (United States)

    Yang, Y; Yuan, Y J; Sun, L T; Feng, Y C; Fang, X; Cao, Y; Lu, W; Zhang, X Z; Zhao, H W

    2014-11-01

    Experimental evidence of the property of transverse coupling of beam from Electron Cyclotron Resonance (ECR) ion source is presented. It is especially of interest for an ECR ion source, where the cross section of extracted beam is not round along transport path due to the magnetic confinement configuration. When the ions are extracted and accelerated through the descending axial magnetic field at the extraction region, the horizontal and vertical phase space strongly coupled. In this study, the coupling configuration between the transverse phase spaces of the beam from ECR ion source is achieved by beam back-tracking simulation based on the measurements. The reasonability of this coupling configuration has been proven by a series of subsequent simulations.

  13. Waveguiding and bending modes in a plasma photonic crystal bandgap device

    Energy Technology Data Exchange (ETDEWEB)

    Wang, B., E-mail: bwang17@stanford.edu; Cappelli, M. A. [Stanford Plasma Physics Laboratory, Department of Mechanical Engineering, Stanford University, Stanford, California 94305 (United States)

    2016-06-15

    Waveguiding and bending modes are investigated in a fully tunable plasma photonic crystal. The plasma device actively controls the propagation of free space electromagnetic waves in the S to X band of the microwave spectrum. An array of discharge plasma tubes form a square crystal lattice exhibiting a well-defined bandgap, with individual active switching of the plasma elements to allow for waveguiding and bending modes to be generated dynamically. We show, through simulations and experiments, the existence of transverse electric (TE) mode waveguiding and bending modes.

  14. Operational status of the Magnum-PSI linear plasma device

    NARCIS (Netherlands)

    Scholten, J.; van Emmichoven, P. A. Zeijlma; van Eck, H. J. N.; Smeets, P. H. M.; De Temmerman, G. C.; Brons, S.; van den Berg, M. A.; van der Meiden, H. J.; van de Pol, M.J.; M. F. Graswinckel,; Groen, P. W. C.; Poelman, A. J.; Genuit, J. W.

    2013-01-01

    The construction phase of the linear plasma generator Magnum-PSI at the FOM institute DIFFER has been completed and the facility has been officially opened in March 2012. The scientific program to gain more insight in the plasma–wall interactions relevant for ITER and future fusion reactors has

  15. ECR ion source with electron gun

    Science.gov (United States)

    Xie, Z.Q.; Lyneis, C.M.

    1993-10-26

    An Advanced Electron Cyclotron Resonance ion source having an electron gun for introducing electrons into the plasma chamber of the ion source is described. The ion source has a injection enclosure and a plasma chamber tank. The plasma chamber is defined by a plurality of longitudinal magnets. The electron gun injects electrons axially into the plasma chamber such that ionization within the plasma chamber occurs in the presence of the additional electrons produced by the electron gun. The electron gun has a cathode for emitting electrons therefrom which is heated by current supplied from an AC power supply while bias potential is provided by a bias power supply. A concentric inner conductor and outer conductor carry heating current to a carbon chuck and carbon pusher which hold the cathode in place and also heat the cathode. In the Advanced Electron Cyclotron Resonance ion source, the electron gun replaces the conventional first stage used in prior electron cyclotron resonance ion generators. 5 figures.

  16. Plasma effect in silicon charge coupled devices (CCDs)

    Energy Technology Data Exchange (ETDEWEB)

    Estrada, J., E-mail: estrada@fnal.gov [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Molina, J., E-mail: jmolina@ing.una.py [Facultad de Ingenieria, Universidad Nacional de Asuncion, Laboratorio de Mecanica y Energia, Campus de la UNA, San Lorenzo 2160 (Paraguay); Blostein, J.J., E-mail: jeronimo@cab.cnea.gov.ar [CONICET (Argentina); Centro Atomico Bariloche, Comision Nacional de Energia Atomica, Bariloche (Argentina); Fernandez, G., E-mail: fmoroni.guillermo@gmail.com [Universidad Nacional del Sur, Bahia Blanca (Argentina)

    2011-02-11

    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 agree 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 {sup 10}B 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.

  17. Design and Construction of a Dense Plasma Focus Device

    Science.gov (United States)

    1976-10-01

    electrode design .. ........ ..... 27 3.3.2 The outer electrode design .. ....... ...... 29 3.3.3 End-plate spacer design. .. ....... ....... 31 3.3.4...artificial plasma for his own personal use, with nuclear fusion probably the most exciting and so- cially constructive application. Nuclear fusion has the...current sheath against the inner surface of the outer electrode. The axial accelerating force (j x B ) varies as i/r across the annulus z G z and results

  18. Surface modifications of fusion reactor relevant materials on exposure to fusion grade plasma in plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Niranjan, Ram, E-mail: niranjan@barc.gov.in [Applied Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Rout, R.K.; Srivastava, R. [Applied Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Chakravarthy, Y. [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Mishra, P. [Materials Processing Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Kaushik, T.C.; Gupta, Satish C. [Applied Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2015-11-15

    Graphical abstract: - Highlights: • Exposure of materials (W, Ni, SS, Mo and Cu) to fusion plasma in a plasma focus device. • The erosion and the formations of blisters, pores, craters, micro-cracks after irradiation. • The structural phase transformation in the SS sample after irradiation. • The surface layer alloying of the samples with the plasma focus anode material. - Abstract: An 11.5 kJ plasma focus (PF) device was used here to irradiate materials with fusion grade plasma. The surface modifications of different materials (W, Ni, stainless steel, Mo and Cu) were investigated using various available techniques. The prominent features observed through the scanning electron microscope on the sample surfaces were erosions, cracks, blisters and craters after irradiations. The surface roughness of the samples increased multifold after exposure as measured by the surface profilometer. The X-ray diffraction analysis indicated the changes in the microstructures and the structural phase transformation in surface layers of the samples. We observed change in volumes of austenite and ferrite phases in the stainless steel sample. The energy dispersive X-ray spectroscopic analysis suggested alloying of the surface layer of the samples with elements of the PF anode. We report here the comparative analysis of the surface damages of materials with different physical, thermal and mechanical properties. The investigations will be useful to understand the behavior of the perspective materials for future fusion reactors (either in pure form or in alloy) over the long operations.

  19. Laser induced fluorescence measurements of axial velocity, velocity shear, and parallel ion temperature profiles during the route to plasma turbulence in a linear magnetized plasma device

    Science.gov (United States)

    Chakraborty Thakur, S.; Adriany, K.; Gosselin, J. J.; McKee, J.; Scime, E. E.; Sears, S. H.; Tynan, G. R.

    2016-11-01

    We report experimental measurements of the axial plasma flow and the parallel ion temperature in a magnetized linear plasma device. We used laser induced fluorescence to measure Doppler resolved ion velocity distribution functions in argon plasma to obtain spatially resolved axial velocities and parallel ion temperatures. We also show changes in the parallel velocity profiles during the transition from resistive drift wave dominated plasma to a state of weak turbulence driven by multiple plasma instabilities.

  20. The MaPLE device of Saha Institute of Nuclear Physics: construction and its plasma aspects.

    Science.gov (United States)

    Pal, Rabindranath; Biswas, Subir; Basu, Subhasis; Chattopadhyay, Monobir; Basu, Debjyoti; Chaudhuri, Manis; Chowdhuri, Manis

    2010-07-01

    The Magnetized Plasma Linear Experimental (MaPLE) device is a low cost laboratory plasma device at Saha Institute of Nuclear Physics fabricated in-house with the primary aim of studying basic plasma physics phenomena such as plasma instabilities, wave propagation, and their nonlinear behavior in magnetized plasma regime in a controlled manner. The machine is specially designed to be a versatile laboratory device that can provide a number of magnetic and electric scenario to facilitate such studies. A total of 36 number of 20-turn magnet coils, designed such as to allow easy handling, is capable of producing a uniform, dc magnetic field of about 0.35 T inside the plasma chamber of diameter 0.30 m. Support structure of the coils is planned in an innovative way facilitating straightforward fabrication and easy positioning of the coils. Further special feature lies in the arrangement of the spacers between the coils that can be maneuvered rather easily to create different magnetic configurations. Various methods of plasma production can be suitably utilized according to the experimental needs at either end of the vacuum vessel. In the present paper, characteristics of a steady state plasma generated by electron cyclotron resonance method using 2.45 GHz microwave power are presented. Scans using simple probe drives revealed that a uniform and long plasma column having electron density approximately 3-5x10(10) cm(-3) and temperature approximately 7-10 eV, is formed in the center of the plasma chamber which is suitable for wave launching experiments.

  1. Study on neutron emission from 2.2 kJ plasma focus device

    Science.gov (United States)

    Talukdar, N.; Neog, N. K.; Borthakur, T. K.

    2014-06-01

    The neutron emission from a low energy (2.2 kJ) plasma focus device operated in deuterium medium has been investigated by employing photo-multiplier tube (PMT) and bubble dosimeter. The neutron emission is found to be pressure dependent and anisotropic in nature. In most cases of plasma focus shots, the PMT signal shows double pulses of neutron emission with different intensities and widths. An interesting relation between intensity of hard X-ray and neutron emission is also observed.

  2. Electron cyclotron resonance heating in a short cylindrical plasma ...

    Indian Academy of Sciences (India)

    produced plasmas are still not well-investigated. To study these ECR-produced plasmas ... Section 4 contains the presentation and interpretation of the main experimental results. Section 5 contains the discussion and the final conclusion. 2.

  3. Gyrotron-driven high current ECR ion source for boron-neutron capture therapy neutron generator

    Energy Technology Data Exchange (ETDEWEB)

    Skalyga, V., E-mail: skalyga.vadim@gmail.com [Institute of Applied Physics, RAS, 46 Ul’yanova st., 603950 Nizhny Novgorod (Russian Federation); Lobachevsky State University of Nizhny Novgorod (UNN), 23 Gagarina st., 603950 Nizhny Novgorod (Russian Federation); Izotov, I.; Golubev, S.; Razin, S. [Institute of Applied Physics, RAS, 46 Ul’yanova st., 603950 Nizhny Novgorod (Russian Federation); Sidorov, A. [Institute of Applied Physics, RAS, 46 Ul’yanova st., 603950 Nizhny Novgorod (Russian Federation); Lobachevsky State University of Nizhny Novgorod (UNN), 23 Gagarina st., 603950 Nizhny Novgorod (Russian Federation); Maslennikova, A. [Lobachevsky State University of Nizhny Novgorod (UNN), 23 Gagarina st., 603950 Nizhny Novgorod (Russian Federation); Nizhny Novgorod State Medical Academy, 10/1 Minina Sq., 603005 Nizhny Novgorod (Russian Federation); Volovecky, A. [Lobachevsky State University of Nizhny Novgorod (UNN), 23 Gagarina st., 603950 Nizhny Novgorod (Russian Federation); Kalvas, T.; Koivisto, H.; Tarvainen, O. [University of Jyvaskyla, Department of Physics, PO Box 35 (YFL), 40500 Jyväskylä (Finland)

    2014-12-21

    Boron-neutron capture therapy (BNCT) is a perspective treatment method for radiation resistant tumors. Unfortunately its development is strongly held back by a several physical and medical problems. Neutron sources for BNCT currently are limited to nuclear reactors and accelerators. For wide spread of BNCT investigations more compact and cheap neutron source would be much more preferable. In present paper an approach for compact D–D neutron generator creation based on a high current ECR ion source is suggested. Results on dense proton beams production are presented. A possibility of ion beams formation with current density up to 600 mA/cm{sup 2} is demonstrated. Estimations based on obtained experimental results show that neutron target bombarded by such deuteron beams would theoretically yield a neutron flux density up to 6·10{sup 10} cm{sup −2}/s. Thus, neutron generator based on a high-current deuteron ECR source with a powerful plasma heating by gyrotron radiation could fulfill the BNCT requirements significantly lower price, smaller size and ease of operation in comparison with existing reactors and accelerators.

  4. Statistical characterization of the reproducibility of neutron emission of small plasma focus devices

    Energy Technology Data Exchange (ETDEWEB)

    Tarifeno-Saldivia, Ariel; Soto, Leopoldo [Comision Chilena de Energia Nuclear (CCHEN), Casilla 188-D, Santiago (Chile); Center for Research and Applications in Plasma Physics and Pulsed Power, P4 (Chile) and Departamento de Ciencias Fisicas, Universidad Andres Bello, Republica 220, Santiago (Chile)

    2012-09-15

    The purpose of this work is to discuss the techniques related to the detection of fast pulsed neutrons produced in plasma focus (PF) devices, the statistical analysis of the corresponding data, and the methodologies for evaluation of the device performance in low emission neutron sources. A general mathematical framework is presented for the assessment of the reproducibility of the neutron emission of small PF devices given the shot-to-shot distribution and detector efficiency. The effect on the reproducibility in case of using two independent detectors is also discussed. The analysis is applied to the neutron emission of the plasma focus device PF-50J operating in repetitive mode (0.1-0.5 Hz and 65 J bank energy).

  5. Innovation in the development of plasma propulsion devices in Israel

    Science.gov (United States)

    Lev, Dan R.

    2017-04-01

    In this paper we review plasma propulsion development approach which focuses on innovation. We then bring the example of the state of Israel in general, and Rafael in particular, and show how it has adopted an innovative approach to develop a low power Hall thruster and a low current cathode. To present one special test-case of innovation we elaborate upon the development process of a heaterless hollow cathode that was developed at Rafael. In particular, by presenting the cathode characterization and wear test results we demonstrate that the heaterless cathode developed has a sufficiently wide operational range and may operate continuously for 1,500 hours without any measurable degradation in performance.

  6. Study on discharge plasma in a cylindrical inertial electrostatic confinement fusion device

    Science.gov (United States)

    Buzarbaruah, N.; Dutta, N. J.; Borgohain, D.; Mohanty, S. R.; Bailung, H.

    2017-08-01

    Deuterium plasma has been produced in a cylindrical inertial electrostatic confinement fusion device using hot and cold cathode discharges and the plasma parameters are determined by employing an electrostatic probe. The plasma temperature and density are estimated at optimum experimental conditions and it is noted that the plasma temperature is 3 eV in the case of hot cathode discharge whereas 10 eV in the case of the cold cathode discharge. The plasma density as determined is two orders more in the case of the hot cathode discharge than the other. The probe is also used to observe the ion oscillation in the negative potential well that is formed in between the cathode grid and chamber (anode). The observation of spontaneous oscillation along with the harmonics has been reported.

  7. MEASUREMENT OF THE HIGH ENERGY COMPONENT OF THE X-RAY SPECTRA INTHE VENUS ECR ION SOURCE

    Energy Technology Data Exchange (ETDEWEB)

    Leitner, Daniela; Benitez, Janilee Y.; Lyneis, Claude M.; Todd,Damon S.; Ropponen,Tommi; Ropponen,Janne; Koivisto, Hannu; Gammino, Santo

    2007-11-15

    High performance electron cyclotron resonance (ECR) ion sources, such as VENUS (Versatile ECR for Nuclear Science), produce large amounts of x-rays. By studying their energy spectra, conclusions can be drawn about the electron heating process and the electron confinement. In addition, the bremsstrahlung from the plasma chamber is partly absorbed by the cold mass of the superconducting magnet adding an extra heat load to the cryostat. Germanium or NaI detectors are generally used for x-ray measurements. Due to the high x-ray flux from the source, the experimental set-up to measure bremsstrahlung spectra from ECR ion sources is somewhat different than for the traditional nuclear physics measurements these detectors are generally used for. In particular the collimation and background shielding can be problematic. In this paper we will discuss the experimental set-up for such a measurement, the energy calibration and background reduction, the correction for detector efficiency, the shielding of the detector and collimation of the x-ray flux. We will present x-ray energy spectra and cryostat heating rates in dependence of various ion source parameters such as confinement fields, minimum B-field, rf power and heating frequency.

  8. Experimental investigation on electrical characteristics and dose measurement of dielectric barrier discharge plasma device used for therapeutic application

    Science.gov (United States)

    Shahbazi Rad, Zahra; Abbasi Davani, Fereydoun

    2017-04-01

    In this research, a Dielectric Barrier Discharge (DBD) plasma device operating in air has been made. The electrical characteristics of this device like instantaneous power, dissipated power, and discharge capacitance have been measured. Also, the effects of applied voltage on the dissipated power and discharge capacitance of the device have been investigated. The determination of electrical parameters is important in DBD plasma device used in living tissue treatment for choosing the proper treatment doses and preventing the destructive effects. The non-thermal atmospheric pressure DBD plasma source was applied for studying the acceleration of blood coagulation time, in vitro and wound healing time, in vivo. The citrated blood drops coagulated within 5 s treatment time by DBD plasma. The effects of plasma temperature and electric field on blood coagulation have been studied as an affirmation of the applicability of the constructed device. Also, the effect of constructed DBD plasma on wound healing acceleration has been investigated.

  9. Characteristics of electron cyclotron resonance plasma formed by ...

    Indian Academy of Sciences (India)

    m3. When the ECR appears .... capacitor bank power supply assisted by ECR plasma, formed by LHCD system. The main parameters of the ..... voltage is gradually decreased from shot to shot, till the discharge ceases to form. We refer these ...

  10. Study of X-ray emission from plasma focus device using vacuum photodiode

    Science.gov (United States)

    Talukdar, N.; Borthakur, T. K.; Neog, N. K.

    2013-10-01

    A newly fabricated vacuum photodiode (VPD) is used to measure time resolved X-ray emission and electron temperature from plasma focus device operated in hydrogen medium. The VPD signals are compared with the PIN diode signal and observed to be of similar in nature. The acquired signals from VPD are deduced to measure electron temperature and X-ray radiated power for four different anode tips (cylindrical, diverging, oval and converging). The electron temperatures are found to be 0.64, 1.5, 0.60 and 0.55 keV for cylindrical, diverging, oval and converging anode tips respectively in hydrogen plasma. The X-ray radiated powers are observed to be varying with respect to the shape of the anode tips and it is found highest in case of converging tip and lowest for the diverging one. Results indicate that VPD could efficiently be employed as an X-ray diagnostics in plasma focus device.

  11. Study of X-ray emission from plasma focus device using vacuum photodiode

    Energy Technology Data Exchange (ETDEWEB)

    Talukdar, N.; Borthakur, T.K., E-mail: tkborthakur@yahoo.co.uk; Neog, N.K.

    2013-10-21

    A newly fabricated vacuum photodiode (VPD) is used to measure time resolved X-ray emission and electron temperature from plasma focus device operated in hydrogen medium. The VPD signals are compared with the PIN diode signal and observed to be of similar in nature. The acquired signals from VPD are deduced to measure electron temperature and X-ray radiated power for four different anode tips (cylindrical, diverging, oval and converging). The electron temperatures are found to be 0.64, 1.5, 0.60 and 0.55 keV for cylindrical, diverging, oval and converging anode tips respectively in hydrogen plasma. The X-ray radiated powers are observed to be varying with respect to the shape of the anode tips and it is found highest in case of converging tip and lowest for the diverging one. Results indicate that VPD could efficiently be employed as an X-ray diagnostics in plasma focus device.

  12. Capillary flow-driven microfluidic device with wettability gradient and sedimentation effects for blood plasma separation

    Science.gov (United States)

    Maria, M. Sneha; Rakesh, P. E.; Chandra, T. S.; Sen, A. K.

    2017-01-01

    We report a capillary flow-driven microfluidic device for blood-plasma separation that comprises a cylindrical well between a pair of bottom and top channels. Exposure of the well to oxygen-plasma creates wettability gradient on its inner surface with its ends hydrophilic and middle portion hydrophobic. Due to capillary action, sample blood self-infuses into bottom channel and rises up the well. Separation of plasma occurs at the hydrophobic patch due to formation of a ‘self-built-in filter’ and sedimentation. Capillary velocity is predicted using a model and validated using experimental data. Sedimentation of RBCs is explained using modified Steinour’s model and correlation between settling velocity and liquid concentration is found. Variation of contact angle on inner surface of the well is characterized and effects of well diameter and height and dilution ratio on plasma separation rate are investigated. With a well of 1.0 mm diameter and 4.0 mm height, 2.0 μl of plasma was obtained (from <10 μl whole blood) in 15 min with a purification efficiency of 99.9%. Detection of glucose was demonstrated with the plasma obtained. Wetting property of channels was maintained by storing in DI water under vacuum and performance of the device was found to be unaffected over three weeks. PMID:28256564

  13. Analysis of the interaction of deuterium plasmas with tungsten in the Fuego-Nuevo II device

    Science.gov (United States)

    Ramos, Gonzalo; Castillo, Fermín; Nieto, Martín; Martínez, Marco; Rangel, José; Herrera-Velázquez, Julio

    2012-10-01

    Tungsten is one of the main candidate materials for plasma-facing components in future fusion power plants. The Fuego-Nuevo II, a plasma focus device, which can produce dense magnetized helium and deuterium plasmas, has been adapted to address plasma-facing materials questions. In this paper we present results of tungsten targets exposed to deuterium plasmas in the Fuego Nuevo II device, using different experimental conditions. The plasma generated and accelerated in the coaxial gun is expected to have, before the pinch, energies of the order of hundreds eV and velocities of the order of 40,000 m s-1. At the pinch, the ions are reported to have energies of the order of 1.5 keV at most. The samples, analysed with a scanning electron microscope (SEM) in cross section show a damage profile to depths of the order of 580 nm, which are larger than those expected for ions with 1.5 keV, and may be evidence of ion acceleration. An analysis with the SRIM (Stopping Range of Ions in Matter) package calculations is shown.

  14. Automation of plasma protein binding assay using rapid equilibrium dialysis device and Tecan workstation.

    Science.gov (United States)

    Ye, Zhengqi; Zetterberg, Craig; Gao, Hong

    2017-06-05

    Binding of drug molecules to plasma proteins is an important parameter in assessing drug ADME properties. Plasma protein binding (PPB) assays are routinely performed during drug discovery and development. A fully automated PPB assay was developed using rapid equilibrium dialysis (RED) device and Tecan workstation coupled to an automated incubator. The PPB assay was carried out in unsealed RED plates which allowed the assay to be fully automated. The plasma pH was maintained at 7.4 during the 6-h dialysis under 2% CO2 condition. The samples were extracted with acetonitrile and analyzed by liquid chromatography tandem mass spectrometry. The percent bound results of 10 commercial drugs in plasma protein binding were very similar between the automated and manual assays, and were comparable to literature values. The automated assay increases laboratory productivity and is applicable to high-throughput screening of drug protein binding in drug discovery. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Effect of a Biased Probe on the Afterglow Operation of an ECR4 Ion Source

    CERN Document Server

    Hill, C E; Wenander, F; Wolf, B H

    2000-01-01

    Various experiments have been performed on a 14.5 GHz ECR4 in order to improve the ion yield. The source runs in pulsed afterglow mode, and provides currents ~120 emA of Pb27+ to the CERN Heavy Ion Facility on an operational basis. In the search for higher beam intensities, the effects of a pulsed biased disk on axis at the injection side were investigated with different pulse timing and voltage settings. No proof for absolute higher intensities was seen for any of these modifications. However, the yield from a poorly tuned/low-performing source could be improved and the extracted pulse was less noisy with bias voltage applied. The fast response on the bias implies that increases/decreases are not due to ionisation processes. A good tune for high yield of high charge states during the afterglow coincides with a high plasma potential.

  16. Removal of Elemental Mercury from a Gas Stream Facilitated by a Non-Thermal Plasma Device

    Energy Technology Data Exchange (ETDEWEB)

    Charles Mones

    2006-12-01

    Mercury generated from anthropogenic sources presents a difficult environmental problem. In comparison to other toxic metals, mercury has a low vaporization temperature. Mercury and mercury compounds are highly toxic, and organic forms such as methyl mercury can be bio-accumulated. Exposure pathways include inhalation and transport to surface waters. Mercury poisoning can result in both acute and chronic effects. Most commonly, chronic exposure to mercury vapor affects the central nervous system and brain, resulting in neurological damage. The CRE technology employs a series of non-thermal, plasma-jet devices to provide a method for elemental mercury removal from a gas phase by targeting relevant chemical reactions. The technology couples the known chemistry of converting elemental mercury to ionic compounds by mercury-chlorine-oxygen reactions with the generation of highly reactive species in a non-thermal, atmospheric, plasma device. The generation of highly reactive metastable species in a non-thermal plasma device is well known. The introduction of plasma using a jet-injection device provides a means to contact highly reactive species with elemental mercury in a manner to overcome the kinetic and mass-transfer limitations encountered by previous researchers. To demonstrate this technology, WRI has constructed a plasma test facility that includes plasma reactors capable of using up to four plasma jets, flow control instrumentation, an integrated control panel to operate the facility, a mercury generation system that employs a temperature controlled oven and permeation tube, combustible and mercury gas analyzers, and a ductless fume hood designed to capture fugitive mercury emissions. Continental Research and Engineering (CR&E) and Western Research Institute (WRI) successfully demonstrated that non-thermal plasma containing oxygen and chlorine-oxygen reagents could completely convert elemental mercury to an ionic form. These results demonstrate potential the

  17. Generation of multi-charged high current ion beams using the SMIS 37 gas-dynamic electron cyclotron resonance (ECR) ion source

    Energy Technology Data Exchange (ETDEWEB)

    Dorf, M. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zorin, V. G. [Russian Academy of Sciences (RAS), Nizhny Novgorod (Russian Federation). Inst. of Applied Physics; Sidorov, A. V. [Russian Academy of Sciences (RAS), Nizhny Novgorod (Russian Federation). Inst. of Applied Physics; Bokhanov, A. F. [Russian Academy of Sciences (RAS), Nizhny Novgorod (Russian Federation). Inst. of Applied Physics; Izotov, I. V. [Russian Academy of Sciences (RAS), Nizhny Novgorod (Russian Federation). Inst. of Applied Physics; Razin, S. V. [Russian Academy of Sciences (RAS), Nizhny Novgorod (Russian Federation). Inst. of Applied Physics; Skalyga, V. A. [Russian Academy of Sciences (RAS), Nizhny Novgorod (Russian Federation). Inst. of Applied Physics

    2013-06-02

    A gas-dynamic ECR ion source (GaDIS) is distinguished by its ability to produce high current and high brightness beams of moderately charged ions. Contrary to a classical ECR ion source where the plasma confinement is determined by the slow electron scattering into an empty loss-cone, the higher density and lower electron temperature in a GaDIS plasma lead to an isotropic electron distribution with the confinement time determined by the prompt gas-dynamic flow losses. As a result, much higher ion fluxes are available, however a decrease in the confinement time of the GaDIS plasma lowers the ion charge state. The gas-dynamic ECR ion source concept has been successfully realized in the SMIS 37 experimental facility operated at the Institute of Applied Physics, Russia. The use of high-power (~100 kW) microwave (37.5 GHz) radiation provides a dense plasma (~1013 cm-3) with a relatively low electron temperature (~50- 100 eV) and allows for the generation of high current (~1 A/cm2) beams of multi-charged ions. In this work we report on the present status of the SMIS 37 ion source and discuss the advanced numerical modeling of ion beam extraction using the particle-in-cell code WARP

  18. Development of a new experimental device for long-duration magnetic reconnection in weakly ionized plasma

    Science.gov (United States)

    Yanai, Ryoma; Kaminou, Yasuhiro; Nishida, Kento; Inomoto, Michiaki

    2016-10-01

    Magnetic reconnection is a universal phenomenon which determines global structure and energy conversion in magnetized plasmas. Many experimental studies have been carried out to explore the physics of magnetic reconnection in fully ionized condition. However, it is predicted that the behavior of magnetic reconnection in weakly ionized plasmas such as solar chromosphere plasma will show different behavior such as ambipolar diffusion caused by interaction with neutral particles. In this research, we are developing a new experimental device to uncover the importance of ambipolar diffusion during magnetic reconnection in weakly ionized plasmas. We employ an inverter-driven rotating magnetic fields technique, which is used for generating steady azimuthal plasma current, to establish long-duration ( 1 ms) anti-parallel reconnection with magnetic field of 5 mT in weakly ionized plasma. We will present development status and initial results from the new experimental setup. This work was supported by JSPS A3 Foresight Program ``Innovative Tokamak Plasma Startup and Current Drive in Spherical Torus'', Giant-in Aid for Scientific Research (KAKENHI) 15H05750, 15K14279, 26287143 and the NIFS Collaboration Research program (NIFS14KNWP004).

  19. ERO modeling of Cr sputtering in the linear plasma device PSI-2

    Science.gov (United States)

    Eksaeva, A.; Borodin, D.; Kreter, A.; Nishijima, D.; Pospieszczyk, A.; Schlummer, T.; Ertmer, S.; Terra, A.; Unterberg, B.; Kirschner, A.; Romazanov, J.; Brezinsek, S.; Rasinski, M.; Henderson, S.; O’Mullane, M.; Summers, H.; Bluteau, M.; Marenkov, E.

    2017-12-01

    The prediction of the first wall deterioration and possible plasma contamination by impurities is a high priority task for ITER. 3D Monte-Carlo code ERO is a tool for modeling of eroded impurity transport and spectroscopy in plasma devices useful for experiment interpretation. Chromium (Cr) is a fusion-relevant reactor wall element (e.g. component of RAFM steels expected for use in DEMO). Linear plasma devices including PSI-2 are effective tools for investigations of plasma-surface interaction effects, allowing continuous plasma operation and good control over irradiation parameters. Experiments on Cr sputtering were conducted at PSI-2. In these experiments the Cr erosion was measured by three techniques: mass loss of the sample, quartz micro-balance of deposited impurities at a distance from it and optical emission spectroscopy. Experiments were modeled with the 3D Monte-Carlo code ERO, previously validated by application to similar experiments with tungsten (W). The simulations are demonstrated to reproduce the main experimental outcomes proving the quality of the sputtering data used. A significant focuses of the paper is the usage and validation of atomic data (resent metastable-resolved dataset from ADAS) for interpretation of Cr spectroscopy. Initial population of quasi-metastable state was fitted by matching the modeling with the experimental line intensity profiles.

  20. Study on neutron emission from 2.2 kJ plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Talukdar, N.; Neog, N. K.; Borthakur, T. K., E-mail: tkborthakur@yahoo.co.uk [Centre of Plasma Physics, Institute for Plasma Research, Sonapur 782402, Kamrup, Assam (India)

    2014-06-15

    The neutron emission from a low energy (2.2 kJ) plasma focus device operated in deuterium medium has been investigated by employing photo-multiplier tube (PMT) and bubble dosimeter. The neutron emission is found to be pressure dependent and anisotropic in nature. In most cases of plasma focus shots, the PMT signal shows double pulses of neutron emission with different intensities and widths. An interesting relation between intensity of hard X-ray and neutron emission is also observed.

  1. Plasma-on-chip device for stable irradiation of cells cultured in media with a low-temperature atmospheric pressure plasma.

    Science.gov (United States)

    Okada, Tomohiro; Chang, Chun-Yao; Kobayashi, Mime; Shimizu, Tetsuji; Sasaki, Minoru; Kumagai, Shinya

    2016-09-01

    We have developed a micro electromechanical systems (MEMS) device which enables plasma treatment for cells cultured in media. The device, referred to as the plasma-on-chip, comprises microwells and microplasma sources fabricated together in a single chip. The microwells have through-holes between the microwells and microplasma sources. Each microplasma source is located on the backside of each microwells. The reactive components generated by the microplasma sources pass through the through-holes and reach cells cultured in the microwells. In this study, a plasma-on-chip device was modified for a stable plasma treatment. The use of a dielectric barrier discharge (DBD) technique allowed a stable plasma treatment up to 3 min. The plasma-on-chip with the original electrode configuration typically had the maximum stable operation time of around 1 min. Spectral analysis of the plasma identified reactive species such as O and OH radicals that can affect the activity of cells. Plasma treatment was successfully performed on yeast (Saccharomyces cerevisiae) and green algae (Chlorella) cells. While no apparent change was observed with yeast, the treatment degraded the activity of the Chlorella cells and decreased their fluorescence. The device has the potential to help understand interactions between plasma and cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Development of a 10 GHz “Multi-Mode” ECR, Ion Source for the Production of Multiply Charged Ions from Metallic Elements

    Science.gov (United States)

    Trassl, R.; Thompson, W. R.; Broetz, F.; Pawlowsky, M.; McCullough, R. W.; Salzborn, E.

    An all-permanent magnet ECR “multi-mode” ion source with emphasis on the production of metallic ions has been built. The main feature of this ion source is a stepped plasma chamber with a larger diameter in the resonance region in order to allow the propagation of higher microwave modes than the ground mode. Ions from metallic elements can be produced using both the insertion technique and an evaporation oven. First spectra obtained for Oxygen and Bismuth are shown.

  3. Accessibility condition of wave propagation and multicharged ion production in electron cyclotron resonance ion source plasma.

    Science.gov (United States)

    Kato, Yushi; Yano, Keisuke; Nishiokada, Takuya; Nagaya, Tomoki; Kimura, Daiju; Kumakura, Sho; Imai, Youta; Hagino, Shogo; Otsuka, Takuro; Sato, Fuminobu

    2016-02-01

    A new tandem type source of electron cyclotron resonance (ECR) plasmas has been constructing for producing synthesized ion beams in Osaka University. Magnetic mirror field configuration with octupole magnets can be controlled to various shape of ECR zones, namely, in the 2nd stage plasma to be available by a pair mirror and a supplemental coil. Noteworthy correlations between these magnetic configurations and production of multicharged ions are investigated in detail, as well as their optimum conditions. We have been considering accessibility condition of electromagnetic and electrostatic waves propagating in ECR ion source plasma, and then investigated their correspondence relationships with production of multicharged ions. It has been clarified that there exits efficient configuration of ECR zones for producing multicharged ion beams experimentally, and then has been suggested from detail accessibility conditions on the ECR plasma that new resonance, i.e., upper hybrid resonance, must have occurred.

  4. Measurement of erosion in helicon plasma thrusters using the VASIMR® VX-CR device

    Science.gov (United States)

    Del Valle Gamboa, Juan Ignacio; Castro-Nieto, Jose; Squire, Jared; Carter, Mark; Chang-Diaz, Franklin

    2015-09-01

    The helicon plasma source is one of the principal stages of the high-power VASIMR® electric propulsion system. The VASIMR® VX-CR experiment focuses solely on this stage, exploring the erosion and long-term operation effects of the VASIMR helicon source. We report on the design and operational parameters of the VX-CR experiment, and the development of modeling tools and characterization techniques allowing the study of erosion phenomena in helicon plasma sources in general, and stand-alone helicon plasma thrusters (HPTs) in particular. A thorough understanding of the erosion phenomena within HPTs will enable better predictions of their behavior as well as more accurate estimations of their expected lifetime. We present a simplified model of the plasma-wall interactions within HPTs based on current models of the plasma density distributions in helicon discharges. Results from this modeling tool are used to predict the erosion within the plasma-facing components of the VX-CR device. Experimental techniques to measure actual erosion, including the use of coordinate-measuring machines and microscopy, will be discussed.

  5. Numerical Analysis of Amirkabir Plasma Focus (APF) Device for Neon and Argon Gases

    Science.gov (United States)

    Niknam Sharak, M.; Goudarzi, S.; Raeisdana, A.; Jafarabadi, M.

    2013-04-01

    In this paper the experimental results in different working conditions in Amirkabir Plasma Focus (APF) Device have been compared with the numerical results of a two-dimensional simulation code based on Lee's model. The experiments were done with pure Neon and Argon as operating gases over a wide range of working conditions (gas pressures and discharge voltages). It is observed that by a proper choice for values of the efficiency factors, comparison between numerical and experimental results shows a good agreement.

  6. Breakthrough in 4? ion emission mechanism understanding in plasma focus devices

    OpenAIRE

    Sohrabi, Mehdi; Zarinshad, Arefe; Habibi, Morteza

    2016-01-01

    Ion emission angular distribution mechanisms in plasma focus devices (PFD) have not yet been well developed and understood being due to the lack of an efficient wide-angle ion distribution image detection system to characterize a PFD space in detail. Present belief is that the acceleration of ions points from ?anode top? upwards in forward direction within a small solid angle. A breakthrough is reported in this study, by mega-size position-sensitive polycarbonate ion image detection systems i...

  7. Design and development of a LIBS system on linear plasma device PSI-2 for in situ real-time diagnostics of plasma-facing materials

    Directory of Open Access Journals (Sweden)

    X. Jiang

    2017-08-01

    Full Text Available Laser induced breakdown spectroscopy (LIBS is a strong candidate for detecting and monitoring the H/D/T content on the surface of plasma facing components (PFCs due to its capability of fast direct in situ measurement in extreme environment (e.g., vacuum, magnetic field, long distance, complex geometry. To study the feasibilities and encounter the challenges of LIBS on plasma devices, a LIBS system has been set up on the linear plasma device PSI-2. A number of key parameters including laser energy, the influence of magnetic field and the persistence of laser induced plasma are studied. Real-time measurements of deuterium outgassing on tungsten samples exposed to deuterium plasma of 1025 D/m2 are performed in the first 40–130 min after plasma exposure. The experimental results are compared to the calculations in the literature.

  8. Electrical characterization and experimental results in the SPEED4 plasma focus device

    Science.gov (United States)

    Zambra, Marcelo; Soto, Juan Carlos; Silva, Patricio; Sylvester, Gustavo; Pavez, Cristian; Moreno, Jose; Soto, Leopoldo

    2008-11-01

    The pulsed power SPEED4 generator has a capacitor bank system of 1,25 μF in a Marx configuration to produce up to 100 kV, a maximum current up to ~700 kA, and 6,25 kJ of stored energy. In the plasma focus mode, this device has been prepared for the study of the emission of X-rays and neutrons in the Laboratory of Plasma Physics and Plasma Technologies of the Chilean Nuclear Energy Commission. The present experimental results report about the electrical characterization as well as preliminary results using Hydrogen like filling gas. Pinch evidences in the high voltage and current derivative electrical signals are presented in this work and preliminary arguments are given in order to achieve an optimal operation.

  9. Atmospheric pressure plasma jets: an overview of devices and new directions

    Science.gov (United States)

    Winter, J.; Brandenburg, R.; Weltmann, K.-D.

    2015-12-01

    Atmospheric pressure plasma jets have a long history of more than 50 years. During this time their design and plasma generation mechanism has been developed and adapted to various fields of applications. This review aims at giving an overview of jet devices by starting with a brief history of their development. This is followed by an overview of commonly used terms and definitions as well as a survey of different classification schemes (e.g. geometry, excition frequency or specific energy input) described in literature. A selective update of new designs and novel research achievments on atmospheric pressure plasma jets published in 2012 or later shows the impressive variety and rapid development of the field. Finally, a brief outlook on the future trends and directions is given.

  10. ERO modelling of tungsten erosion in the linear plasma device PSI-2

    Directory of Open Access Journals (Sweden)

    A. Eksaeva

    2017-08-01

    Full Text Available Series of experiments on tungsten (W erosion and transport in Argon (Ar plasma were conducted at the linear plasma device PSI-2. W erosion was measured with three independent methods: WΙ spectroscopy, mass loss and quartz micro-balance (QMB deposition sensor. Consistent set of data produced in these experiments was interpreted using the 3D ERO code simulations, which have reproduced all the main trends observed. Influence of the physical model assumptions (e.g. energy and angular distributions of sputtered particles was demonstrated. The effect of WΙ effective quasi-metastable (MS state population dynamics on spectroscopy measurements is shown; the characteristic relaxation time is determined. The measured physical sputtering yields for W are close to the simulated data obtained in the binary collision approximation (BCA approach (SDTrimSP code. The remaining discrepancies between simulations and the experiment, mostly in spectroscopy, are accounted to the uncertainties in the plasma parameters and atomic data.

  11. Electrical characterization and experimental results in the SPEED4 plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Zambra, Marcelo; Silva, Patricio; Sylvester, Gustavo; Pavez, Cristian; Moreno, Jose; Soto, Leopoldo [Comision Chilena de EnergIa Nuclear, Casilla 188-D, Santiago (Chile); Soto, Juan Carlos [Universidad de Santiago de Chile, Santiago (Chile)], E-mail: mzambra@cchen.cl

    2008-11-01

    The pulsed power SPEED4 generator has a capacitor bank system of 1,25 {mu}F in a Marx configuration to produce up to 100 kV, a maximum current up to {approx}700 kA, and 6,25 kJ of stored energy. In the plasma focus mode, this device has been prepared for the study of the emission of X-rays and neutrons in the Laboratory of Plasma Physics and Plasma Technologies of the Chilean Nuclear Energy Commission. The present experimental results report about the electrical characterization as well as preliminary results using Hydrogen like filling gas. Pinch evidences in the high voltage and current derivative electrical signals are presented in this work and preliminary arguments are given in order to achieve an optimal operation.

  12. Impact ionization and tunneling operations in charge-plasma dopingless device

    Science.gov (United States)

    Kim, Minsuk; Kim, Yoonjoong; Lim, Doohyeok; Woo, Sola; Im, Kyeungmin; Cho, Jinsun; Kang, Hyungu; Kim, Sangsig

    2017-11-01

    In this paper, we present the impact ionization and tunneling operations in a newly designed dopingless device. Our proposed device functions selectively-as either a p-channel impact-ionization MOSFET (p-IMOS) or an n-channel tunneling field-effect transistor (n-TFET)-according to the bias conditions. To realize the dopingless device, the charge-plasma effect is employed to induce n- or p-type regions without any doping process, by choosing an electrode metal with an appropriate work function. The band diagrams, I-V characteristics, subthreshold swings (SS), and carrier-concentration profiles of the device under the p-IMOS and n-TFET operation modes are analyzed in our study, using a commercial device simulator. The device yields an extremely low SS of 0.53 mV/dec under the p-IMOS operation mode. It also exhibits a low off-current of approximately 10-14 A/μm and a high ION/IOFF of approximately 108, under the n-TFET operation mode.

  13. Moderation of neoclassical impurity accumulation in high temperature plasmas of helical devices

    CERN Document Server

    Velasco, J L; Satake, S; Alonso, A; Nunami, M; Yokoyama, M; Sato, M; Dinklage, A; Estrada, T; Fontdecaba, J M; Liniers, M; McCarthy, K J; Medina, F; Van Milligen, B Ph; Ochando, M; Parra, F; Sugama, H; Zhezhera, A

    2016-01-01

    Achieving impurity and helium ash control is a crucial issue in the path towards fusion-grade magnetic confinement devices, and this is particularly the case of helical reactors, whose low-collisionality ion-root operation scenarios usually display a negative radial electric field which is expected to cause inwards impurity pinch. In these work we discuss, based on experimental measurements and standard predictions of neoclassical theory, how plasmas of very low ion collisionality, similar to those observed in the impurity hole of the Large Helical Device, can be an exception to this general rule, and how a negative radial electric field can coexist with an outward impurity flux. This interpretation is supported by comparison with documented discharges available in the International Stellarator-Heliotron Profile Database, and it can be extrapolated to show that achievement of high ion temperature in the core of helical devices is not fundamentally incompatible with low core impurity content.

  14. A novel high-efficiency stable atmospheric microwave plasma device for fluid processing based on ridged waveguide

    Science.gov (United States)

    Xiao, Wei; Huang, Kama; He, Jianbo; Wu, Ying

    2017-09-01

    The waveguide-based microwave plasma device is widely used to generate atmospheric plasma for some industrial applications. Nevertheless, the traditional tapered waveguide device has limited power efficiency and produces unstable plasma. A novel ridged waveguide with an oblique hole is proposed to produce microwave atmospheric plasma for fluid processing. By using the ridged waveguide, the microwave field can be well focused, which can sustain plasma at relatively low power. Besides, an oblique hole is used to decrease the power reflection and generate a stable plasma torch especially in the case of high flowing rates. Experiments have been performed with the air flowing rates ranging from 500 l h-1 to 1000 l h-1 and the microwave working frequency of 2.45 GHz. The results show that in comparison with the conventional tapered waveguide, this novel device can both sustain plasma at relative low power and increase the power transfer efficiency by 11% from microwave to plasma. Moreover, both devices are used to process the waste gas-CO and CH4. Significantly, the removal efficiency for CO and CH4 can be increased by 19.7% and 32% respectively in the ridged waveguide compared with the tapered waveguide. It demonstrates that the proposed device possesses a great potential in industrial applications because of its high efficiency and stable performance.

  15. New Results with the superconducting ECR ion source VENUS

    Energy Technology Data Exchange (ETDEWEB)

    Lyneis, C.M.; Leitner, D.; Abbott, S.R.; Dwinell, R.D.; Leitner,M.; Silver, C.S.; Taylor, C.

    2004-05-13

    During the last year, the VENUS ECR ion source was commissioned at 18 GHz and preparations for 28 GHz operation, which is set to begin early in 2004, are now underway. The goal of the VENUS ECR ion source project as the RIA R&D injector is the production of 240emA of U30+, a high current medium charge state beam. On the other hand, as an injector ion source for the 88-Inch Cyclotron the design objective is the production of 5emA of U48+, a low current, very high charge state beam. During the commissioning phase with 18 GHz, tests with various gases and recently metals have been performed with up to 2000 W RF power and the performance is very promising. For example, 1100 e mu A of O6+,180 e mu A of Ar12+, 150 emA of Xe20+ and 100 emA of Bi24+ were produced in the early commissioning phase, ranking VENUS among the currently highest performance 18 GHz ECR ion sources. The emittance of the beams produced at 18 GHz was measured with a two axis emittance scanner. In FY04 a 10 kW, 28 GHz gyrotron system will be added, which will enable VENUS to reach full performance. The performance of the VENUS ion source, low energy beam transport (LEBT) and its closed loop cryogenic system are described in the paper. Recently, a new high temperature axial oven has been installed in the source and the first results on metal beams such as bismuth are given. The design of the 28 GHz, 10 kW gyrotron system is also be described. During the last year, the VENUS ECR ion source was commissioned at 18 GHz and preparations for 28 GHz operation, which is set to begin early in 2004, are now underway. The goal of the VENUS ECR+, a high current medium charge state beam. On the other hand, as an injector ion source for the 88-Inch Cyclotron the design objective is the production of 5 emA of U48+, a low current, very high charge state beam. During the commissioning phase with 18 GHz, tests with various gases and recently metals have been performed with up to 2000 W RF power and the performance is

  16. Mitochondria and the insect steroid hormone receptor (EcR): A complex relationship.

    Science.gov (United States)

    Vafopoulou, Xanthe; Steel, Colin G H

    2016-10-01

    The actions of the insect steroid molting hormones, ecdysteroids, on the genome of target cells has been well studied, but little is known of their extranuclear actions. We previously showed in Rhodnius prolixus that much of the ecdysteroid receptor (EcR) resides in the cytoplasm of various cell types and undergoes shuttling between nucleus and cytoplasm with circadian periodicity, possibly using microtubules as tracks for translocation to the nucleus. Here we report that cytoplasmic EcR appears to be also involved in extranuclear actions of ecdysteroids by association with the mitochondria. Western blots of subcellular fractions of brain lysates revealed that EcR is localized in the mitochondrial fraction, indicating an intimate association of EcR with mitochondria. Confocal laser microscopy and immunohistochemistry using anti-EcR revealed abundant co-localization of EcR with mitochondria in brain neurons and their axons, especially intense in the subplasmalemmal region, raising the possibility of EcR involvement in mitochondrial functions in subplasmalemmal microdomains. When mitochondria are dispersed by disruption of microtubules with colchicine, EcR remains associated with mitochondria showing strong receptor association with mitochondria. Treatment in vitro with ecdysteroids of brains of developmentally arrested R. prolixus (containing neither ecdysteroids nor EcR) induces EcR and abundant co-localization with mitochondria in neurons, concurrently with a sharp increase of the mitochondrial protein COX 1, suggesting involvement of EcR in mitochondrial function. These findings align EcR with various vertebrate steroid receptors, where actions of steroid receptors on mitochondria are widely known and suggest that steroid receptors across distant phyla share similar functional attributes. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Automated system for efficient microwave power coupling in an S-band ECR ion source driven under different operating conditions

    Energy Technology Data Exchange (ETDEWEB)

    Muguira, L., E-mail: lmuguira@essbilbao.org [ESS-Bilbao, Edificio Rectorado, Vivero de Empresas, 48940 Leioa (Bizkaia) (Spain); Portilla, J. [University of Basque Country (UPV/EHU), Department of Electricity and Electronics, Science and Technology Faculty, 48940 Leioa (Bizkaia) (Spain); Gonzalez, P.J.; Garmendia, N.; Feuchtwanger, J. [ESS-Bilbao, Edificio Rectorado, Vivero de Empresas, 48940 Leioa (Bizkaia) (Spain); Etxebarria, V. [University of Basque Country (UPV/EHU), Department of Electricity and Electronics, Science and Technology Faculty, 48940 Leioa (Bizkaia) (Spain); Eguiraun, M.; Arredondo, I.; Miracoli, R.; Belver, D. [ESS-Bilbao, Edificio Rectorado, Vivero de Empresas, 48940 Leioa (Bizkaia) (Spain)

    2014-03-21

    This article presents an automated system for optimizing the microwave power coupling to the plasma generated in a proton/deuteron Electron Cyclotron Resonance (ECR) source, based on a specific model of a rectangular waveguide triple-stub tuner and the integrated measurement and control electronics, helping to get stable plasma states. The control and improvement of the RF power absorption into the plasma is a complex process, essential for the ion source development and optimization under different operating conditions. A model and a matching algorithm for the triple-stub tuner have been developed and, besides, different methods to accurately measure the power transfer in a waveguide RF system have been studied and deployed in the ESS-Bilbao ion source system. The different parts have been integrated through a controller, which allows to run an automatic plasma matching system in closed loop. The behavior of the system implemented for low and high power regimes has been tested under different conditions: with several load impedances, with plasma inside the chamber, in continuous wave and pulsed wave operation modes, demonstrating power absorption typically over 90% in all the ion source configurations. The developed system allows to achieve significant improvement in the ECR ion source power absorption efficiency, both in continuous and pulsed mode. The automatic tuning unit enhances the system operation finding an optimum solution much faster than manually, also behaving as an adaptive system able to respond in few pulses to ion source configuration changes to maintain the power coupling as high as possible. - Highlights: • An automated system optimizing plasma and microwave power interaction is presented. • A model and a matching algorithm for the triple-stub tuner have been developed. • Different methods to measure the power transfer have been studied and deployed. • The system works for low or high power regimes under different ion source conditions.

  18. A Novel Micro Cold Atmospheric Plasma Device for Glioblastoma Both In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Zhitong Chen

    2017-05-01

    Full Text Available Cold atmospheric plasma (CAP treatment is a rapidly expanding and emerging technology for cancer treatment. Direct CAP jet irradiation is limited to the skin and it can also be invoked as a supplement therapy during surgery as it only causes cell death in the upper three to five cell layers. However, the current cannulas from which the plasma emanates are too large for intracranial applications. To enhance efficiency and expand the applicability of the CAP method for brain tumors and reduce the gas flow rate and size of the plasma jet, a novel micro-sized CAP device (µCAP was developed and employed to target glioblastoma tumors in the murine brain. Various plasma diagnostic techniques were applied to evaluate the physics of helium µCAP such as electron density, discharge voltage, and optical emission spectroscopy (OES. The direct and indirect effects of µCAP on glioblastoma (U87MG-RedFluc cancer cells were investigated in vitro. The results indicate that µCAP generates short- and long-lived species and radicals (i.e., hydroxyl radical (OH, hydrogen peroxide (H2O2, and nitrite (NO2−, etc. with increasing tumor cell death in a dose-dependent manner. Translation of these findings to an in vivo setting demonstrates that intracranial µCAP is effective at preventing glioblastoma tumor growth in the mouse brain. The µCAP device can be safely used in mice, resulting in suppression of tumor growth. These initial observations establish the µCAP device as a potentially useful ablative therapy tool in the treatment of glioblastoma.

  19. Overdense plasma generation in a compact ion source

    Science.gov (United States)

    Castro, G.; Mascali, D.; Gammino, S.; Torrisi, G.; Romano, F. P.; Celona, L.; Altana, C.; Caliri, C.; Gambino, N.; Lanaia, D.; Miracoli, R.; Neri, L.; Sorbello, G.

    2017-05-01

    Electron cyclotron resonance ion sources (ECRIS) are widely used plasma based machines for the production of intense ion beams in science and industry. The performance of modern devices is limited by the presence of the density cut-off, above which electromagnetic (EM) waves sustaining the plasma are reflected. We hereby discuss the systematic data analysis of electrostatic wave generation in an ECR prototype operating at 3.75 GHz-0.1 THz. In particular, electron Bernstein waves (EBW) have been excited. EBW have already been generated in large-scale plasma devices for thermonuclear fusion purposes. In ion sources where L c ˜ λ RF (L c being the plasma chamber size and λ RF the pumping wave wavelength) the EM field assumes a modal behaviour; thus both plasma and EM field self-organize so that no optical-like wave launching is possible (i.e. the cavity effect dominates on the optical path). The collected data, however, supported by 3D full-wave simulations, actually demonstrate that a Budden-type X-B conversion scenario can be established above some critical RF power thresholds, operating in an off-ECR regime. The generation and absorption of the EBW has been demonstrated by the presence of three peculiar signatures: along with the establishment of an overdense plasma, generation of supra-thermal electrons and modification (non-linear broadening) of the EM spectrum measured within the plasma have been observed. At the threshold establishing such a heating regime, the collected data provide evidence for a fast rotation of the electron fluid.

  20. Characterisation and Performance of The CERN ECR4 Ion Source

    CERN Document Server

    Hill, C E; Chamings, J A; Coco, V; Küchler, D; Lombardi, A M; Sargsya, E; Scrivens, R; ECRIS'04

    2005-01-01

    To optimise the heavy ion injector for the LHC, a good knowledge of the parameters of the ECR4 ion source and the beam transport in the Low Energy Beam Transport (LEBT) for a lead ion beam is necessary. Results of the emittance measurements of the full beam (O + Pb) leaving the source using a scanning slit and profile monitor will be presented. Furthermore, the emittance of a single charge state after the source has been measured using a solenoid scan coupled to a guillotine and spectrometer. The results for last year’s operation for the SPS fixed target physics with indium will also be presented.

  1. Hole injection enhancement in organic light emitting devices using plasma treated graphene oxide

    Energy Technology Data Exchange (ETDEWEB)

    Jesuraj, P. Justin; Parameshwari, R. [Centre for Nanoscience and Nanotechnology, School of Physics, Bharathidasan University, Tiruchirappalli, 620 024, Tamil Nadu (India); Kanthasamy, K.; Koch, J. [Institut für Festkörperphysik, ATMOS, Appelstr. 2, D-30167, Hannover (Germany); Pfnür, H. [Institut für Festkörperphysik, ATMOS, Appelstr. 2, D-30167, Hannover (Germany); Laboratorium für Nano- und Quantene$ngineering, Schneiderberg 30, D-30167, Hannover (Germany); Jeganathan, K., E-mail: kjeganathan@yahoo.com [Centre for Nanoscience and Nanotechnology, School of Physics, Bharathidasan University, Tiruchirappalli, 620 024, Tamil Nadu (India)

    2017-03-01

    Graphical abstract: Plasma treated Graphene oxide for hole injection enhancement in OLEDs. - Highlights: • Oxygen (O{sub 2}) and hydrogen (H{sub 2}) plasma exposed graphene oxide (GO) sheets have been demonstrated as hole buffer layers in OLEDs. • O{sub 2} plasma exposure induces assimilation of oxygen contents in GO lattice resulting in improved work function that reduced the hole injection barrier further. Whereas, H{sub 2} plasma contrastingly reduced the GO by excluding oxygen which ensuing lower work function. • X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy investigations reveal the capricious amount of oxygen in GO lattice and its corresponding work function variations. • GO and O{sub 2} plasma treated GO significantly improves the current efficiency of OLEDs more than one order with notable reduction in turn on voltage. - Abstract: The hole injection layer (HIL) with high work function (WF) is desirable to reduce the injection barrier between anode and hole transport layer in organic light emitting devices (OLED). Here, we report a novel approach to tune the WF of graphene oxide (GO) using oxygen and hydrogen plasma treatment and its hole injection properties in OLEDs. The mild exposure of oxygen plasma on GO (O{sub 2}-GO) significantly reduces the injection barrier by increasing the WF of anode (4.98 eV) through expansion of C−O bonds. In contrast, the hole injection barrier was drastically increased for hydrogen plasma treated GO (H{sub 2}-GO) layers as the WF is lowered by the contraction of C−O bond. By employing active O{sub 2}-GO as HIL in OLEDs found to exhibit superior current efficiency of 4.2 cd/A as compared to 3.3 cd/A for pristine GO. Further, the high injection efficiency of O{sub 2}-GO infused hole only device can be attributed to the improved energy level matching. Ultraviolet and X-ray photoelectron spectroscopy were used to correlate the WF of HIL infused anode towards the enhanced performance of

  2. DLTS Analysis and Interface Engineering of Solution Route Fabricated Zirconia Based MIS Devices Using Plasma Treatment

    Science.gov (United States)

    Kumar, Arvind; Mondal, Sandip; Koteswara Rao, K. S. R.

    2018-02-01

    In this work, we have fabricated low-temperature sol-gel spin-coated and oxygen (O2) plasma treated ZrO2 thin film-based metal-insulator-semiconductor devices. To understand the impact of plasma treatment on the Si/ZrO2 interface, deep level transient spectroscopy measurements were performed. It is reported that the interface state density ( D it) comes down to 7.1 × 1010 eV-1 cm-2 from 4 × 1011 eV-1 cm-2, after plasma treatment. The reduction in D it is around five times and can be attributed to the passivation of oxygen vacancies near the Si/ZrO2 interface, as they try to relocate near the interface. The energy level position ( E T) of interfacial traps is estimated to be 0.36 eV below the conduction band edge. The untreated ZrO2 film displayed poor leakage behavior due to the presence of several traps within the film and at the interface; O2 plasma treated films show improved leakage current density as they have been reduced from 5.4 × 10-8 A/cm2 to 1.98 × 10-9 A/cm2 for gate injection mode and 6.4 × 10-8 A/cm2 to 6.3 × 10-10 A/cm2 for substrate injection mode at 1 V. Hence, we suggest that plasma treatment might be useful in future device fabrication technology.

  3. DLTS Analysis and Interface Engineering of Solution Route Fabricated Zirconia Based MIS Devices Using Plasma Treatment

    Science.gov (United States)

    Kumar, Arvind; Mondal, Sandip; Koteswara Rao, K. S. R.

    2017-11-01

    In this work, we have fabricated low-temperature sol-gel spin-coated and oxygen (O2) plasma treated ZrO2 thin film-based metal-insulator-semiconductor devices. To understand the impact of plasma treatment on the Si/ZrO2 interface, deep level transient spectroscopy measurements were performed. It is reported that the interface state density (D it) comes down to 7.1 × 1010 eV-1 cm-2 from 4 × 1011 eV-1 cm-2, after plasma treatment. The reduction in D it is around five times and can be attributed to the passivation of oxygen vacancies near the Si/ZrO2 interface, as they try to relocate near the interface. The energy level position (E T) of interfacial traps is estimated to be 0.36 eV below the conduction band edge. The untreated ZrO2 film displayed poor leakage behavior due to the presence of several traps within the film and at the interface; O2 plasma treated films show improved leakage current density as they have been reduced from 5.4 × 10-8 A/cm2 to 1.98 × 10-9 A/cm2 for gate injection mode and 6.4 × 10-8 A/cm2 to 6.3 × 10-10 A/cm2 for substrate injection mode at 1 V. Hence, we suggest that plasma treatment might be useful in future device fabrication technology.

  4. Process automation system for integration and operation of Large Volume Plasma Device

    Energy Technology Data Exchange (ETDEWEB)

    Sugandhi, R., E-mail: ritesh@ipr.res.in; Srivastava, P.K.; Sanyasi, A.K.; Srivastav, Prabhakar; Awasthi, L.M.; Mattoo, S.K.

    2016-11-15

    Highlights: • Analysis and design of process automation system for Large Volume Plasma Device (LVPD). • Data flow modeling for process model development. • Modbus based data communication and interfacing. • Interface software development for subsystem control in LabVIEW. - Abstract: Large Volume Plasma Device (LVPD) has been successfully contributing towards understanding of the plasma turbulence driven by Electron Temperature Gradient (ETG), considered as a major contributor for the plasma loss in the fusion devices. Large size of the device imposes certain difficulties in the operation, such as access of the diagnostics, manual control of subsystems and large number of signals monitoring etc. To achieve integrated operation of the machine, automation is essential for the enhanced performance and operational efficiency. Recently, the machine is undergoing major upgradation for the new physics experiments. The new operation and control system consists of following: (1) PXIe based fast data acquisition system for the equipped diagnostics; (2) Modbus based Process Automation System (PAS) for the subsystem controls and (3) Data Utilization System (DUS) for efficient storage, processing and retrieval of the acquired data. In the ongoing development, data flow model of the machine’s operation has been developed. As a proof of concept, following two subsystems have been successfully integrated: (1) Filament Power Supply (FPS) for the heating of W- filaments based plasma source and (2) Probe Positioning System (PPS) for control of 12 number of linear probe drives for a travel length of 100 cm. The process model of the vacuum production system has been prepared and validated against acquired pressure data. In the next upgrade, all the subsystems of the machine will be integrated in a systematic manner. The automation backbone is based on 4-wire multi-drop serial interface (RS485) using Modbus communication protocol. Software is developed on LabVIEW platform using

  5. A 5 kA pulsed power supply for inductive and plasma loads in large volume plasma device

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, P. K., E-mail: pkumar@ipr.res.in; Singh, S. K.; Sanyasi, A. K.; Awasthi, L. M., E-mail: kushagra.lalit@gmail.com; Mattoo, S. K. [Institute for Plasma Research, Gandhinagar (India)

    2016-07-15

    This paper describes 5 kA, 12 ms pulsed power supply for inductive load of Electron Energy Filter (EEF) in large volume plasma device. The power supply is based upon the principle of rapid sourcing of energy from the capacitor bank (2.8 F/200 V) by using a static switch, comprising of ten Insulated Gate Bipolar Transistors (IGBTs). A suitable mechanism is developed to ensure equal sharing of current and uniform power distribution during the operation of these IGBTs. Safe commutation of power to the EEF is ensured by the proper optimization of its components and by the introduction of over voltage protection (>6 kV) using an indigenously designed snubber circuit. Various time sequences relevant to different actions of power supply, viz., pulse width control and repetition rate, are realized through optically isolated computer controlled interface.

  6. A 5 kA pulsed power supply for inductive and plasma loads in large volume plasma device

    Science.gov (United States)

    Srivastava, P. K.; Singh, S. K.; Sanyasi, A. K.; Awasthi, L. M.; Mattoo, S. K.

    2016-07-01

    This paper describes 5 kA, 12 ms pulsed power supply for inductive load of Electron Energy Filter (EEF) in large volume plasma device. The power supply is based upon the principle of rapid sourcing of energy from the capacitor bank (2.8 F/200 V) by using a static switch, comprising of ten Insulated Gate Bipolar Transistors (IGBTs). A suitable mechanism is developed to ensure equal sharing of current and uniform power distribution during the operation of these IGBTs. Safe commutation of power to the EEF is ensured by the proper optimization of its components and by the introduction of over voltage protection (>6 kV) using an indigenously designed snubber circuit. Various time sequences relevant to different actions of power supply, viz., pulse width control and repetition rate, are realized through optically isolated computer controlled interface.

  7. Películas amorfas de SixCyN depositadas mediante ECR-PECVD

    Directory of Open Access Journals (Sweden)

    Barbadillo, L.

    2000-08-01

    Full Text Available ECR-PECVD processes with several activators and diluent gases were performed to obtain films with carbon and nitrogen at low temperatures. In all cases methane and nitrogen were used as precursors of C and N species. The characterization of the samples was done using Fourier transform infrared spectroscopy (FTIR and spectroscopic ellipsometry. The FTIR measurements show that the presence of little amounts of silane in the plasma substantially alters the composition of the films, while the addition of hydrogen has no appreciable effects in their formation. Moreover, the use of argon or neon as diluent of the gas precursors is closely related to the degree of activation of the methane molecule, as observed in the optical emission spectra recorded in every process. The application of rf fields during depositions only changes the growth rates.

    Se han realizado procesos de plasma de resonancia ciclotrón electrónica (ECR con diferentes activadores y diluyentes gaseosos para obtener películas con carbono y nitrógeno a bajas temperaturas. En todos los casos se emplearon metano y nitrógeno como precursores de especies de C y N. La caracterización de las muestras se realizó mediante espectroscopía de infrarrojos por transformada de Fourier y elipsometría espectroscópica. Las medidas de espectroscopía de infrarrojos muestran que la presencia de pequeñas cantidades de silano en el plasma altera sustancialmente la composición de las películas, mientras que la adición de hidrógeno no tiene efectos apreciables en la formación de las mismas. Por otra parte, la utilización de argón o neón como diluyentes de los precursores gaseosos está estrechamente relacionada con el grado de activación de las moléculas de metano, según se observa en los espectros de emisión óptica registrados en cada proceso. La aplicación de campos de radiofrecuencia durante los depósitos únicamente varía las velocidades de crecimiento.

  8. Thrust Stand Measurements of the Microwave Assisted Discharge Inductive Plasma Accelerator

    Science.gov (United States)

    Hallock, Ashley K.; Polzin, Kurt A.; Emsellem, Gregory D.

    2011-01-01

    Pulsed inductive plasma thrusters [1-3] are spacecraft propulsion devices in which electrical energy is capacitively stored and then discharged through an inductive coil. This type of pulsed thruster is electrodeless, with a time-varying current in the coil interacting with a plasma covering the face of the coil to induce a plasma current. Propellant is accelerated and expelled at a high exhaust velocity (O(10-100 km/s)) by the Lorentz body force arising from the interaction of the magnetic field and the induced plasma current. While this class of thruster mitigates the life-limiting issues associated with electrode erosion, pulsed inductive plasma thrusters require high pulse energies to inductively ionize propellant. The Microwave Assisted Dis- charge Inductive Plasma Accelerator (MAD-IPA), shown in Fig. 1, is a pulsed inductive plasma thruster that addressees this issue by partially ionizing propellant inside a conical inductive coil before the main current pulse via an electron cyclotron resonance (ECR) discharge. The ECR plasma is produced using microwaves and a static magnetic field from a set of permanent magnets arranged to create a thin resonance region along the inner surface of the coil, restricting plasma formation, and in turn current sheet formation, to a region where the magnetic coupling between the plasma and the theta-pinch coil is high. The use of a conical theta-pinch coil also serves to provide neutral propellant containment and plasma plume focusing that is improved relative to the more common planar geometry of the Pulsed Inductive Thruster (PIT) [1, 2]. In this paper, we describe thrust stand measurements performed to characterize the performance (specific impulse, thrust efficiency) of the MAD-IPA thruster. Impulse data are obtained at various pulse energies, mass flow rates and inductive coil geometries. Dependencies on these experimental parameters are discussed in the context of the current sheet formation and electromagnetic plasma

  9. Hybrid simulation of a parallel collisionless shock in the Large Plasma Device

    CERN Document Server

    Weidl, M S; Jenko, F; Niemann, C

    2016-01-01

    We present two-dimensional hybrid kinetic/magnetohydrodynamic simulations of planned laser-ablation experiments in the Large Plasma Device (LAPD). Our results, based on parameters which have been validated in previous experiments, show that a parallel collisionless shock can begin forming within the available space. Carbon-debris ions that stream along the magnetic-field direction with a blow-off speed of four times the Alfven velocity excite strong magnetic fluctuations, eventually transfering part of their kinetic energy to the surrounding hydrogen ions. This acceleration and compression of the background plasma creates a shock front, which satisfies the Rankine-Hugoniot conditions and can therefore propagate on its own. Furthermore, we analyze the upstream turbulence and show that it is dominated by the right-hand resonant instability.

  10. Measurements of line-averaged electron density of pulsed plasmas using a He-Ne laser interferometer in a magnetized coaxial plasma gun device

    Science.gov (United States)

    Iwamoto, D.; Sakuma, I.; Kitagawa, Y.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

    2012-10-01

    In next step of fusion devices such as ITER, lifetime of plasma-facing materials (PFMs) is strongly affected by transient heat and particle loads during type I edge localized modes (ELMs) and disruption. To clarify damage characteristics of the PFMs, transient heat and particle loads have been simulated by using a plasma gun device. We have performed simulation experiments by using a magnetized coaxial plasma gun (MCPG) device at University of Hyogo. The line-averaged electron density measured by a He-Ne interferometer is 2x10^21 m-3 in a drift tube. The plasma velocity measured by a time of flight technique and ion Doppler spectrometer was 70 km/s, corresponding to the ion energy of 100 eV for helium. Thus, the ion flux density is 1.4x10^26 m-2s-1. On the other hand, the MCPG is connected to a target chamber for material irradiation experiments. It is important to measure plasma parameters in front of target materials in the target chamber. In particular, a vapor cloud layer in front of the target material produced by the pulsed plasma irradiation has to be characterized in order to understand surface damage of PFMs under ELM-like plasma bombardment. In the conference, preliminary results of application of the He-Ne laser interferometer for the above experiment will be shown.

  11. Rapid Atmospheric-Pressure-Plasma-Jet Processed Porous Materials for Energy Harvesting and Storage Devices

    Directory of Open Access Journals (Sweden)

    Jian-Zhang Chen

    2015-01-01

    Full Text Available Atmospheric pressure plasma jet (APPJ technology is a versatile technology that has been applied in many energy harvesting and storage devices. This feature article provides an overview of the advances in APPJ technology and its application to solar cells and batteries. The ultrafast APPJ sintering of nanoporous oxides and 3D reduced graphene oxide nanosheets with accompanying optical emission spectroscopy analyses are described in detail. The applications of these nanoporous materials to photoanodes and counter electrodes of dye-sensitized solar cells are described. An ultrashort treatment (1 min on graphite felt electrodes of flow batteries also significantly improves the energy efficiency.

  12. Open loop control of filament heating power supply for large volume plasma device

    Energy Technology Data Exchange (ETDEWEB)

    Sugandhi, R., E-mail: ritesh@ipr.res.in [Institute for Plasma Research, Gandhinagar, Gujarat 382428 (India); Homi Bhabha National Institute, Mumbai 400094 (India); Srivastava, P.K.; Sanyasi, A.K. [Homi Bhabha National Institute, Mumbai 400094 (India); Srivastav, Prabhakar [Institute for Plasma Research, Gandhinagar, Gujarat 382428 (India); Homi Bhabha National Institute, Mumbai 400094 (India); Awasthi, L.M., E-mail: kushagra.lalit@gmail.com [Institute for Plasma Research, Gandhinagar, Gujarat 382428 (India); Homi Bhabha National Institute, Mumbai 400094 (India); Mattoo, S.K. [Homi Bhabha National Institute, Mumbai 400094 (India)

    2017-02-15

    A power supply (20 V, 10 kA) for powering the filamentary cathode has been procured, interfaced and integrated with the centralized control system of Large Volume Plasma Device (LVPD). Software interface has been developed on the standard Modbus RTU communication protocol. It facilitates the dashboard for configuration, on line status monitoring, alarm management, data acquisition, synchronization and controls. It has been tested for stable operation of the power supply for the operational capabilities. The paper highlights the motivation, interface description, implementation and results obtained.

  13. A very sensitive ion collection device for plasma-laser characterization

    Science.gov (United States)

    Cavallaro, S.; Torrisi, L.; Cutroneo, M.; Amato, A.; Sarta, F.; Wen, L.

    2012-06-01

    In this paper a very sensitive ion collection device, for diagnostic of laser ablated-target plasma, is described. It allows for reducing down to few microvolts the signal threshold at digital scope input. A standard ion collector is coupled to a transimpedance amplifier, specially designed, which increases data acquisition sensitivity by a gain ≈1100 and does not introduce any significant distortion of input signal. By time integration of current intensity, an amount of charge as small as 2.7 × 10-2 pC can be detected for photopeak events.

  14. Design of a 500-kJ Mather-type plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Heidarnia, A., E-mail: a-heidarnia@yahoo.com; Sadighzadeh, A.; Zaeem, A. A.; Damideh, V. [Nuclear Science and Technology Research Institute, Plasma Physics and Nuclear Fusion Research School (Iran, Islamic Republic of)

    2016-12-15

    In this article, design of a 500-kJ Mather-type plasma focus device to achieve 10{sup 11} neutrons/shot is reported. One of its important characteristics is the triple-part anode design. The anode is surrounded by an alumina insulator. The second part of the anode is changeable in order to locate cylindrical, conical, or other shapes of pieces mounted on it. This geometry leads to the easier investigation of the neutron and X-ray emissions of the device. The third part of the anode is for changing the materials exposed to different kinds of radiations. The design parameters are considered by semiempirical and empirical formulas and are sketched by Solidworks software. Also, the peak current and neutron yield are estimated.

  15. Design of a 500-kJ Mather-type plasma focus device

    Science.gov (United States)

    Heidarnia, A.; Sadighzadeh, A.; Zaeem, A. A.; Damideh, V.

    2016-12-01

    In this article, design of a 500-kJ Mather-type plasma focus device to achieve 1011 neutrons/shot is reported. One of its important characteristics is the triple-part anode design. The anode is surrounded by an alumina insulator. The second part of the anode is changeable in order to locate cylindrical, conical, or other shapes of pieces mounted on it. This geometry leads to the easier investigation of the neutron and X-ray emissions of the device. The third part of the anode is for changing the materials exposed to different kinds of radiations. The design parameters are considered by semiempirical and empirical formulas and are sketched by Solidworks software. Also, the peak current and neutron yield are estimated.

  16. Comparative study of neutron emission from a plasma focus device using two different anode shapes

    Energy Technology Data Exchange (ETDEWEB)

    Talukdar, N.; Borthakur, S.; Neog, N. K.; Borthakur, T. K., E-mail: tkborthakur@yahoo.co.uk [Centre of Plasma Physics, Institute for Plasma Research, Sonapur, 782402 Kamrup, Assam (India)

    2016-05-15

    The neutron emission from a low energy (2.2 kJ) plasma focus (PF) device operated with two different shapes (cylindrical and converging) of anodes has been investigated by employing photomultiplier tube and bubble dosimeter. The neutron emission with each anode is analyzed and the results are compared. It is found that the anode shapes strongly influenced the emission of neutron. The X-ray emission is found to be higher in case of converging anode, while neutron emission is found to be higher in case of cylindrical anode. The neutron yield and energy are found to be highly anisotropic in nature which indicates that the beam target mechanism plays a major role in the neutron emission in a PF device. The speed factor as well as the specific heat ratio of pinch column shows a good agreement with the experimentally observed results.

  17. Comparative study of neutron emission from a plasma focus device using two different anode shapes

    Science.gov (United States)

    Talukdar, N.; Borthakur, S.; Neog, N. K.; Borthakur, T. K.

    2016-05-01

    The neutron emission from a low energy (2.2 kJ) plasma focus (PF) device operated with two different shapes (cylindrical and converging) of anodes has been investigated by employing photomultiplier tube and bubble dosimeter. The neutron emission with each anode is analyzed and the results are compared. It is found that the anode shapes strongly influenced the emission of neutron. The X-ray emission is found to be higher in case of converging anode, while neutron emission is found to be higher in case of cylindrical anode. The neutron yield and energy are found to be highly anisotropic in nature which indicates that the beam target mechanism plays a major role in the neutron emission in a PF device. The speed factor as well as the specific heat ratio of pinch column shows a good agreement with the experimentally observed results.

  18. Cold atmospheric pressure plasma for treatment of chronic wounds: drug or medical device?

    Science.gov (United States)

    Kramer, A; Conway, B R; Meissner, K; Scholz, F; Rauch, B H; Moroder, A; Ehlers, A; Meixner, A J; Heidecke, C-D; Partecke, L I; Kietzmann, M; Assadian, O

    2017-08-02

    The use of cold atmospheric pressure plasma (CAPP) as a new therapeutic option to aid the healing of chronic wounds appears promising. Currently, uncertainty exists regarding their classification as medical device or medical drug. Because the classification of CAPP has medical, legal, and economic consequences as well as implications for the level of preclinical and clinical testing, the correct classification is not an academic exercise, but an ethical need. A multidisciplinary team of physicians, surgeons, pharmacists, physicists and lawyers has analysed the physical and technical characteristics as well as legal conditions of the biological action of CAPP. It was concluded that the mode of action of the locally generated CAPP, with its main active components being different radicals, is pharmacological and not physical in nature. Depending on the intended use, CAPP should be classified as a drug, which is generated by use of a medical device directly at the point of therapeutic application.

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

    Energy Technology Data Exchange (ETDEWEB)

    Mascali, David, E-mail: davidmascali@lns.infn.it; Castro, Giuseppe; Celona, Luigi; Neri, Lorenzo; Gammino, Santo [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Biri, Sándor; Rácz, Richárd; Pálinkás, József [Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/c, H-4026 Debrecen (Hungary); Caliri, Claudia [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Università degli Studi di Catania, Dip.to di Fisica e Astronomia, via Santa Sofia 64, 95123 Catania (Italy); Romano, Francesco Paolo [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); CNR, Istituto per i Beni Archeologici e Monumentali, Via Biblioteca 4, 95124 Catania (Italy); Torrisi, Giuseppe [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Università Mediterranea di Reggio Calabria, DIIES, Via Graziella, I-89100 Reggio Calabria (Italy)

    2016-02-15

    An experimental campaign aiming to investigate electron cyclotron resonance (ECR) plasma X-ray emission has been recently carried out at the ECRISs—Electron Cyclotron Resonance Ion Sources laboratory of Atomki based on a collaboration between the Debrecen and Catania ECR teams. In a first series, the X-ray spectroscopy was performed through silicon drift detectors and high purity germanium detectors, characterizing the volumetric plasma emission. The on-purpose developed collimation system was suitable for direct plasma density evaluation, performed “on-line” during beam extraction and charge state distribution characterization. A campaign for correlating the plasma density and temperature with the output charge states and the beam intensity for different pumping wave frequencies, different magnetic field profiles, and single-gas/gas-mixing configurations was carried out. The results reveal a surprisingly very good agreement between warm-electron density fluctuations, output beam currents, and the calculated electromagnetic modal density of the plasma chamber. A charge-coupled device camera coupled to a small pin-hole allowing X-ray imaging was installed and numerous X-ray photos were taken in order to study the peculiarities of the ECRIS plasma structure.

  20. Simulation of the electromagnetic field in a cylindrical cavity of an ECR ions source

    Science.gov (United States)

    Estupiñán, A.; Orozco, E. A.; Dugar-Zhabon, V. D.; Murillo Acevedo, M. T.

    2017-12-01

    Now there are numerous sources for multicharged ions production, each being designed for certain science or technological objectives. Electron cyclotron resonance ion sources (ECRIS) are best suited for designing heavy ion accelerators of very high energies, because they can generate multicharged ion beams at relatively great intensities. In these sources, plasma heating and its confinement are effected predominantly in minimum-B magnetic traps, this type of magnetic trap consist of two current coils used for the longitudinal magnetic confinement and a hexapole system around the cavity to generate a transversal confinement of the plasma. In an ECRIS, the electron cyclotron frequency and the microwave frequency are maintained equal on a quasi-ellipsoidal surface localized in the trap volume. It is crucial to heat electrons to energies sufficient to ionize K- and L-levels of heavy atoms. In this work, we present the preliminary numerical results concerning the space distribution of TE 111 microwave field in a cylindrical cavity. The 3D microwave field is calculated by solving the Maxwell equations through the Yee’s method. The magnetic field of minimum-B configuration is determined using the Biot-Savart law. The parameters of the magnetic system are that which guarantee the ECR surface location in a zone of a reasonably high microwave tension. Additionally, the accuracy of electric and magnetic fields calculations are checked.

  1. Characteristics of the injected ion beam in the ECR charge breeder 1+ -> n+

    CERN Document Server

    Lamy, T; Chauvin, N; Curdy, Jean Claude; Geller, R; Sortais, P; Leroy, R; Lieuvin, M; Villari, A C C

    1999-01-01

    Different ion species (rare gases, alkali, metallic) have been injected on the axis of the MINIMAFIOS - 10 GHz - Electron Cyclotron Resonance Ion Source which is the basics of the 1+ -> n+ method, special attention have been paid to the optics of the incoming beam for the validation of the 1+ -> n+ method for the SPIRAL project (Radioactive Ion Beam facility). The capture of the incoming ion beam by the ECR plasma depends, first, on the relative energy of the incoming ions with respect to the average ion energy in the plasma, and secondly, on the optics of the injection line. The efficiency of the process when varying the potential V n+ of the MINIMAFIOS source with respect to the potential V 1+ applied to the 1+ source (DV=V n+ -V 1+ ) is an image of the energy dispersion of the 1+ beam. 1+ -> n+ spectra efficiencies, DV efficiency dependence for the most efficient charge state obtained, and measured primary beam emittances are given for the Ar, Rb, Pb, Cr. Highest efficiencies obtained are respectively Ar1+...

  2. Interaction of the high energy deuterons with the graphite target in the plasma focus devices based on Lee model

    Energy Technology Data Exchange (ETDEWEB)

    Akel, M., E-mail: pscientific2@aec.org.sy; Alsheikh Salo, S.; Ismael, Sh. [Department of Physics, Atomic Energy Commission, Damascus, P. O. Box 6091 (Syrian Arab Republic); Saw, S. H. [INTI International University, 71800 Nilai (Malaysia); Institute for Plasma Focus Studies, 32 Oakpark Drive, Chadstone VIC 3148 (Australia); Lee, S. [INTI International University, 71800 Nilai (Malaysia); Institute for Plasma Focus Studies, 32 Oakpark Drive, Chadstone VIC 3148 (Australia); Physics Department, University of Malaya, Kuala Lumpur (Malaysia)

    2014-07-15

    Numerical experiments are systematically carried out using the Lee model code extended to compute the ion beams on various plasma focus devices operated with Deuterium gas. The deuteron beam properties of the plasma focus are studied for low and high energy plasma focus device. The energy spectral distribution for deuteron ions ejected from the pinch plasma is calculated and the ion numbers with energy around 1 MeV is then determined. The deuteron–graphite target interaction is studied for different conditions. The yield of the reaction {sup 12}C(d,n){sup 13}N and the induced radioactivity for one and multi shots plasma focus devices in the graphite solid target is investigated. Our results present the optimized high energy repetitive plasma focus devices as an alternative to accelerators for the production of {sup 13}N short lived radioisotopes. However, technical challenges await solutions on two fronts: (a) operation of plasma focus machines at high rep rates for a sufficient period of time (b) design of durable targets that can take the thermal load.

  3. Microcavity Plasma Devices and Arrays Fabricated in Semiconductor, Ceramic, or Metal/polymer Structures: A New Realm of Plasma Physics and Photonics Applications

    Energy Technology Data Exchange (ETDEWEB)

    Eden, J. G.

    2005-07-01

    Micro discharge, or microcavity plasma, is the broad term that has come to be associated with an emerging class of glow discharge devices in which the characteristic spatial dimension of the plasma is nominally < 1 mm. Over the past several years, our laboratory has leveraged fabrication techniques developed largely by the VLSI and MEMs communities to demonstrate a broad spectrum of semiconductor, ceramic, and multi-layer metal/polymer structures (with microcavity cross-sectional dimensions as small as 10 . 10 mu m2) that are promising for a variety of applications, including micro displays, chemical sensors, and medical diagnostics. The remarkable properties of low temperature plasmas confined to mesoscopic dimensions including picoliter . nanoliter volumes, operation at pressures up to one atmosphere (and beyond), and specific power loadings (on a continuous basis) of tens to hundreds of kW-cm3 will be discussed. The breadth of devices now available, the increasing level of functionality, and the promise of further advances as a result of fully integrating nanotechnology will be reviewed. For example, arrays as large as 500 . 500 pixels, each of which is a (50 mum)2 inverted pyramid microcavity device, have been fabricated in 100 mm (4) dia. Si wafers and operated in the rare gases and Ar/N2 gas mixtures. Also, photodetection in the ultraviolet, visible and near-infrared with microplasma devices has been observed by interfacing a low temperature plasma with a semiconductor. Carbon nanotubes grown directly within the microcavity of microplasma devices improve all key performance parameters of the device, and nanoporous Al2O3 grown onto Al by wet chemical processing yields microplasma devices of exceptional stability and lifetime. The opportunities such structures offer for accessing new avenues in plasma physics and photonics will be discussed. (Author)

  4. Preliminary investigation on the use of low current pulsed power Z-pinch plasma devices for the study of early stage plasma instabilities

    Science.gov (United States)

    Kaselouris, E.; Dimitriou, V.; Fitilis, I.; Skoulakis, A.; Koundourakis, G.; Clark, E. L.; Chatzakis, J.; Bakarezos, Μ; Nikolos, I. K.; Papadogiannis, N. A.; Tatarakis, M.

    2018-01-01

    This article addresses key features for the implementation of low current pulsed power plasma devices for the study of matter dynamics from the solid to the plasma phase. The renewed interest in such low current plasma devices lies in the need to investigate methods for the mitigation of prompt seeding mechanisms for the generation of plasma instabilities. The low current when driven into thick wires (skin effect mode) allows for the simultaneous existence of all phases of matter from solid to plasma. Such studies are important for the concept of inertial confinement fusion where the mitigation of the instability seeding mechanisms arising from the very early moments within the target’s heating is of crucial importance. Similarly, in the magnetized liner inertial fusion concept it is an open question as to how much surface non-uniformity correlates with the magneto-Rayleigh–Taylor instability, which develops during the implosion. This study presents experimental and simulation results, which demonstrate that the use of low current pulsed power devices in conjunction with appropriate diagnostics can be important for studying seeding mechanisms for the imminent generation of plasma instabilities in future research.

  5. Three-dimensional two-fluid Braginskii simulations of the large plasma device

    Science.gov (United States)

    Fisher, Dustin M.; Rogers, Barrett N.; Rossi, Giovanni D.; Guice, Daniel S.; Carter, Troy A.

    2015-09-01

    The Large Plasma Device (LAPD) is modeled using the 3D Global Braginskii Solver code. Comparisons to experimental measurements are made in the low-bias regime in which there is an intrinsic E × B rotation of the plasma. In the simulations, this rotation is caused primarily by sheath effects and may be a likely mechanism for the intrinsic rotation seen in LAPD. Simulations show strong qualitative agreement with the data, particularly the radial dependence of the density fluctuations, cross-correlation lengths, radial flux dependence outside of the cathode edge, and camera imagery. Kelvin Helmholtz (KH) turbulence at relatively large scales is the dominant driver of cross-field transport in these simulations with smaller-scale drift waves and sheath modes playing a secondary role. Plasma holes and blobs arising from KH vortices in the simulations are consistent with the scale sizes and overall appearance of those in LAPD camera images. The addition of ion-neutral collisions in the simulations at previously theorized values reduces the radial particle flux by about a factor of two, from values that are somewhat larger than the experimentally measured flux to values that are somewhat lower than the measurements. This reduction is due to a modest stabilizing contribution of the collisions on the KH-modes driving the turbulent transport.

  6. Breakthrough in 4π ion emission mechanism understanding in plasma focus devices.

    Science.gov (United States)

    Sohrabi, Mehdi; Zarinshad, Arefe; Habibi, Morteza

    2016-12-12

    Ion emission angular distribution mechanisms in plasma focus devices (PFD) have not yet been well developed and understood being due to the lack of an efficient wide-angle ion distribution image detection system to characterize a PFD space in detail. Present belief is that the acceleration of ions points from "anode top" upwards in forward direction within a small solid angle. A breakthrough is reported in this study, by mega-size position-sensitive polycarbonate ion image detection systems invented, on discovery of 4π ion emission from the "anode top" in a PFD space after plasma pinch instability and radial run-away of ions from the "anode cathodes array" during axial acceleration of plasma sheaths before the radial phase. These two ion emission source mechanisms behave respectively as a "Point Ion Source" and a "Line Ion Source" forming "Ion Cathode Shadows" on mega-size detectors. We believe that the inventions and discoveries made here will open new horizons for advanced ion emission studies towards better mechanisms understanding and in particular will promote efficient applications of PFDs in medicine, science and technology.

  7. Investigation of the Effect of Plasma Polymerized Siloxane Coating for Enzyme Immobilization and Microfluidic Device Conception

    Directory of Open Access Journals (Sweden)

    Kalim Belhacene

    2016-12-01

    Full Text Available This paper describes the impact of a physical immobilization methodology, using plasma polymerized 1,1,3,3, tetramethyldisiloxane, on the catalytic performance of β-galactosidase from Aspergillus oryzae in a microfluidic device. The β-galactosidase was immobilized by a polymer coating grown by Plasma Enhanced Chemical Vapor Deposition (PEVCD. Combined with a microchannel patterned in the silicone, a microreactor was obtained with which the diffusion through the plasma polymerized layer and the hydrolysis of a synthetic substrate, the resorufin-β-d-galactopyranoside, were studied. A study of the efficiency of the immobilization procedure was investigated after several uses and kinetic parameters of immobilized β-galactosidase were calculated and compared with those of soluble enzyme. Simulation and a modelling approach were also initiated to understand phenomena that influenced enzyme behavior in the physical immobilization method. Thus, the catalytic performances of immobilized enzymes were directly influenced by immobilization conditions and particularly by the diffusion behavior and availability of substrate molecules in the enzyme microenvironment.

  8. Ion Behavior and Gas Mixing in electron cyclotron resonance plasmas as sources of highly charged ions (concept

    NARCIS (Netherlands)

    Melin, G.; Drentje, A. G.; Girard, A.; Hitz, D.

    1999-01-01

    Abstract: An ECR ion source is basically an ECR heated plasma confinement machine, with hot electrons and cold ions. The main parameters of the ion population have been analyzed, including temperature, losses, and confinement time. The "gas mixing" effect has been studied in this context. An

  9. The Current Status of the Magnetoplasma Compressor Device in Belgrade - Study of Plasma Facing Materials Important for Fusion Reactors

    Directory of Open Access Journals (Sweden)

    Nora Trklja

    2015-01-01

    Full Text Available The magnetoplasma compressor, a quasi stationary plasma accelerator, is a source of supersonic compression plasma flow. High plasma parameters of compression flow, large flow velocity and discharge duration enable their efficient usage for development of new plasma technologies, including material surface modification, creation of sub microstructures and nanostructures. In this paper spatial and temporal distribution of emissivity was studied using inverse Abel transform. This has been realized in LabVIEW environment. The plasma flow generated by quasi stationary plasma accelerators can be used for simulation of high energy plasma interaction with different materials of interest for fusion experiments. Surface phenomena are results of specific conditions during plasma flow interaction with target surface. As the next step in our research, spectral analysis of the plasma area around targets surface, after interaction between target and plasma, generated by magnetoplasma compressor, is planned. The first material which will be subjected to interaction with plasma will be a carbon fiber - material of big importance for divertor region in fusion devices.

  10. From Inert Carbon Dioxide to Fuel Methanol by Activation in Plasma Atmosphere

    Science.gov (United States)

    Suarez, Alejandro; Leal-Quiros, Edbertho; Gonzalez, Jorge

    2015-03-01

    The electron-molecules collisions in plasmas are fructiferous field of study, particularly in activation of inert species into extremely active chemical reactants. Several gases such as carbon dioxide, methane, nitrogen, argon, water among others are ionized or simply activated under collisions with electrons creating the complex atmosphere plasmas. Based upon the energy distribution of electrons and the cross section of molecules it is possible to stimulate molecules becoming highly active species. This research explores the assembly of methanol over a surface of Cu-O-Zr catalyst when carbon dioxide reacts with water under the plasma developed into the Electron Cyclotron Resonance device (ECR). The process was continuously monitored by a mass spectrometer and the correspondent results show the formation of methanol. The ECR operated at 10-6 torr assisted with a microwave source of 250 Watts of power; the magnetic field was developed with 300 Amp on Helmholtz coils. The mode of operation of plasma was in cusp, and the electron temperature was 6-eV reported by a single Langmuir probe. The mass spectrometry reported the presence of methanol. The catalysts characterization is reported in form of Scanning Electron Microscopy image, a Raman spectroscopy analysis, and the Electron Dispersive Spectroscopy (EDS).

  11. Low Damage, High Anisotropy Inductively Coupled Plasma for Gallium Nitride based Devices

    KAUST Repository

    Ibrahim, Youssef H.

    2013-05-27

    Group III-nitride semiconductors possess unique properties, which make them versatile materials for suiting many applications. Structuring vertical and exceptionally smooth GaN profiles is crucial for efficient optical device operation. The processing requirements for laser devices and ridge waveguides are stringent as compared to LEDs and other electronic devices. Due to the strong bonding and chemically inert nature of GaN, dry etching becomes a critical fabrication step. The surface morphology and facet etch angle are analyzed using SEM and AFM measurements. The influence of different mask materials is also studied including Ni as well as a SiO2 and resist bilayer. The high selectivity Ni Mask is found to produce high sidewall angles ~79°. Processing parameters are optimized for both the mask material and GaN in order to achieve a highly anisotropic, smooth profile, without resorting to additional surface treatment steps. An optimizing a SF6/O2 plasma etch process resulted in smooth SiO2 mask sidewalls. The etch rate and GaN surface roughness dependence on the RF power was also examined. Under a low 2mTorr pressure, the RF and ICP power were optimized to 150W and 300W respectively, such that a smooth GaN morphology and sidewalls was achieved with reduced ion damage. The The AFM measurements of the etched GaN surface indicate a low RMS roughness ranging from 4.75 nm to 7.66 nm.

  12. Simulations of Super Alfvenic Laser Ablation Experiments in the Large Plasma Device

    Science.gov (United States)

    Clark, Stephen Eric

    Hybrid plasma simulations, consisting of kinetic ions treated using standard Particle- In-Cell (PIC) techniques and an inertialess charge-neutralizing electron fluid, have been used to investigate the properties of collisionless shocks for a number of years. They agree well with sparse data obtained by flying through Earth's bow shock and have been used to model high energy explosions in the ionosphere. In this doctoral dissertation hybrid plasma simulation is used on much smaller scales to model collisionless shocks in a controlled laboratory setting. Initially a two-dimensional hybrid code from Los Alamos National Laboratory was used to find the best experimental parameters for shock formation, and interpret experimental data. It was demonstrated using the hybrid code that the experimental parameters needed to generate a shock in the laboratory are relaxed compared to previous work that was done. It was also shown that stronger shocks can be generated when running into a density gradient. Laboratory experiments at the University of California at Los Angeles using the high energy kJ-class Nd:Glass 1053 nm Raptor laser, and later the low energy yet high repetition rate 25 J Nd:Glass 1053 nm Peening laser have been performed in the Large Plasma Device (LAPD), which have provided some much needed data to benchmark the hybrid simulation method. The LAPD provides a repeatable, quiescent, ambient magnetized plasma to surround the exploding laser produced plasma that is ablated from a High Density Polyethylene (HDPE) target. The plasma density peaks in the machine at ni O(1013 cm-3 ), which is sufficiently dense to strongly couple energy and momentum from a laser ablated carbon plasma ejected from the HDPE target into the magnetized ambient plasma. It has been demonstrated that a sub-critical shock is formed in the LAPD using the high energy Raptor laser, though the data from this experiment is scant. Hybrid simulation was used as an analysis tool for the shock

  13. Ionization efficiency studies for xenon ions with thesuperconducting ECR ion source VENUS

    Energy Technology Data Exchange (ETDEWEB)

    Leitner, Daniela; Lyneis, Claude M.; Todd, DamonS.; Tarvainen,Olli

    2007-06-05

    Ionization efficiency studies for high charge state xenon ions using a calibrated gas leak are presented. A 75% enriched {sup 129}Xe gas leak with a gas flow equivalent to 5.11p{mu}A was used in all the measurements. The experiments were performed at the VENUS (Versatile ECR ion source for Nuclear Science) ion source for 18 GHz, 28 GHz and double frequency operation. Overall, total ionization efficiencies close to 100% and ionization efficiencies into a single charge state up to 22% were measured. The influence of the biased disk on the ionization efficiency was studied and the results were somewhat surprising. When the biased disk was removed from the plasma chamber, the ionization efficiency was dramatically reduced for single frequency operation. However, using double frequency heating the ionization efficiencies achieved without the biased disk almost matched the ionization efficiencies achieved with the biased probe. In addition, we have studied the influence of the support gas on the charge state distribution of the xenon ions. Either pure oxygen or a mixture of oxygen and helium were used as support gases. The addition of a small amount of helium can increase the ionization efficiency into a single charge state by narrowing the charge state distribution. Furthermore by varying the helium flow the most efficient charge state can be shifted over a wide range without compromising the ionization efficiency. This is not possible using only oxygen as support gas. Results from these studies are presented and discussed.

  14. Measurements of ion temperature and flow of pulsed plasmas produced by a magnetized coaxial plasma gun device using an ion Doppler spectrometer

    Science.gov (United States)

    Kitagawa, Y.; Sakuma, I.; Iwamoto, D.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

    2012-10-01

    It is important to know surface damage characteristics of plasma-facing component materials during transient heat and particle loads such as type I ELMs. A magnetized coaxial plasma gun (MCPG) device has been used as transient heat and particle source in ELM simulation experiments. Characteristics of pulsed plasmas produced by the MCPG device play an important role for the plasma material interaction. In this study, ion temperature and flow velocity of pulsed He plasmas were measured by an ion Doppler spectrometer (IDS). The IDS system consists of a light collection system including optical fibers, 1m-spectrometer and a 16 channel photomultiplier tube (PMT) detector. The IDS system measures the width and Doppler shift of HeII (468.58 nm) emission line with the time resolution of 1 μs. The Doppler broadened and shifted spectra were measured with 45 and 135 degree angles with respect to the plasmoid traveling direction. The observed emission line profile was represented by sum of two Gaussian components to determine the temperature and flow velocity. The minor component at around the wavelength of zero-velocity was produced by the stationary plasma. As the results, the ion velocity and temperature were 68 km/s and 19 eV, respectively. Thus, the He ion flow energy is 97 eV. The observed flow velocity agrees with that measured by a time of flight technique.

  15. Effects of broken solenoidal condition of magnetic field in MHD simulation for large helical device plasmas

    Science.gov (United States)

    Takado, W.; Matsumoto, Y.; Watanabe, K. Y.; Tomioka, S.; Oikawa, S.

    2017-09-01

    We studied the effects of the broken solenoidal condition of a magnetic field in linear magnetohydrodynamics (MHD) simulations based on a real coordinate system for Large Helical Device plasmas. Artificial errors of various orders in this condition were introduced into linear MHD simulations and compared. Spurious Fourier modes were observed to be dominant because of the error in the condition. We suggested a criterion, which is expressed as the condition that the ratio of the error force to the Lorentz force is much smaller than 100%, for estimating an acceptable limit of the solenoidal condition error through the simulation results. The effects of a large error in the condition of the analysis of a specified single-mode instability were investigated in addition. Adding a large error in the condition resulted in certain undesirable modes becoming dominant, whereas the desirable mode did not dominate. Thus, a large error in the condition can be harmful to analysis with a focus on specified modes.

  16. A cesium plasma TELEC device for conversion of laser radiation to electric power

    Science.gov (United States)

    Britt, E. J.; Rasor, N. S.; Lee, G.; Billman, K. W.

    1978-01-01

    Tests of the thermoelectronic laser energy converter (TELEC) concept are reported. This device has been devised as a means to convert high-average-power laser radiation into electrical energy, a crucial element in any space laser power transmission scheme using the available high-power/efficiency infrared lasers. Theoretical calculations, based upon inverse bremsstrahlung absorption in a cesium plasma, indicate internal conversion efficiency up to 50% with an overall system efficiency of 42%. The experiments reported were made with a test cell designed to confirm the theoretical model rather than demonstrate efficiency; 10.6-micron laser-beam absorption was limited to about 0.001 of the incident beam by the short absorption region. Nevertheless, confirmatory results were obtained, and the conversion of absorbed radiation to electric power is estimated to be near 10%.

  17. Statistical properties of edge plasma turbulence in the Large Helical Device

    Energy Technology Data Exchange (ETDEWEB)

    Dewhurst, J M; Hnat, B [Centre for Fusion, Space and Astrophysics, Department of Physics, Warwick University, Coventry CV4 7AL (United Kingdom); Ohno, N [EcoTopica Science Institute, Nagoya University, Nagoya 464-8603 (Japan); Dendy, R O [Euratom/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Masuzaki, S; Morisaki, T; Komori, A [National Institute for Fusion Science, Toki 509-5292 (Japan)], E-mail: j.m.dewhurst@warwick.ac.uk

    2008-09-15

    Ion saturation current (I{sub sat}) measurements made by three tips of a Langmuir probe array in the Large Helical Device are analysed for two plasma discharges. Absolute moment analysis is used to quantify properties on different temporal scales of the measured signals, which are bursty and intermittent. Strong coherent modes in some datasets are found to distort this analysis and are consequently removed from the time series by applying bandstop filters. Absolute moment analysis of the filtered data reveals two regions of power-law scaling, with the temporal scale {tau} {approx} 40 {mu}s separating the two regimes. A comparison is made with similar results from the Mega-Amp Spherical Tokamak. The probability density function is studied and a monotonic relationship between connection length and skewness is found. Conditional averaging is used to characterize the average temporal shape of the largest intermittent bursts.

  18. Statistical properties of edge plasma turbulence in the Large Helical Device

    Science.gov (United States)

    Dewhurst, J. M.; Hnat, B.; Ohno, N.; Dendy, R. O.; Masuzaki, S.; Morisaki, T.; Komori, A.

    2008-09-01

    Ion saturation current (Isat) measurements made by three tips of a Langmuir probe array in the Large Helical Device are analysed for two plasma discharges. Absolute moment analysis is used to quantify properties on different temporal scales of the measured signals, which are bursty and intermittent. Strong coherent modes in some datasets are found to distort this analysis and are consequently removed from the time series by applying bandstop filters. Absolute moment analysis of the filtered data reveals two regions of power-law scaling, with the temporal scale τ ≈ 40 µs separating the two regimes. A comparison is made with similar results from the Mega-Amp Spherical Tokamak. The probability density function is studied and a monotonic relationship between connection length and skewness is found. Conditional averaging is used to characterize the average temporal shape of the largest intermittent bursts.

  19. Low-Energy Plasma Focus Device as an Electron Beam Source

    Directory of Open Access Journals (Sweden)

    Muhammad Zubair Khan

    2014-01-01

    Full Text Available A low-energy plasma focus device was used as an electron beam source. A technique was developed to simultaneously measure the electron beam intensity and energy. The system was operated in Argon filling at an optimum pressure of 1.7 mbar. A Faraday cup was used together with an array of filtered PIN diodes. The beam-target X-rays were registered through X-ray spectrometry. Copper and lead line radiations were registered upon usage as targets. The maximum electron beam charge and density were estimated to be 0.31 μC and 13.5×1016/m3, respectively. The average energy of the electron beam was 500 keV. The high flux of the electron beam can be potentially applicable in material sciences.

  20. Low-Energy Plasma Focus Device as an Electron Beam Source

    Science.gov (United States)

    Seong Ling, Yap; Naresh Kumar, Nitturi; Lian Kuang, Lim; Chiow San, Wong

    2014-01-01

    A low-energy plasma focus device was used as an electron beam source. A technique was developed to simultaneously measure the electron beam intensity and energy. The system was operated in Argon filling at an optimum pressure of 1.7 mbar. A Faraday cup was used together with an array of filtered PIN diodes. The beam-target X-rays were registered through X-ray spectrometry. Copper and lead line radiations were registered upon usage as targets. The maximum electron beam charge and density were estimated to be 0.31 μC and 13.5 × 1016/m3, respectively. The average energy of the electron beam was 500 keV. The high flux of the electron beam can be potentially applicable in material sciences. PMID:25544952

  1. Efficient Consumer Response (ECR: a survey of the Australian grocery industry

    Directory of Open Access Journals (Sweden)

    Paula Swatman

    1998-05-01

    Full Text Available Efficient consumer response (ECR is a U.S. supply chain management strategy which attempts to address the inefficiencies which have led to excessive inventory and unnecessary costs at all levels within the grocery industry supply chain. This paper discusses the traditional grocery store format, the supermarket, and the ways in which inefficient business practices developed in the U.S. grocery supply chain; and discusses the major business activities needed for successful implementation of ECR. The paper then presents a brief summary of the results of a survey of ECR knowledge and usage within the Australian grocery industry, which is the initial phase of a long term research project whose main purpose is to evaluate ECR as it applies to that industry.

  2. Experimental study of the performance of a very small repetitive plasma focus device in different working conditions

    Energy Technology Data Exchange (ETDEWEB)

    Goudarzi, S., E-mail: sgoudarzi@aeoi.org.ir; Babaee, H.; Esmaeli, A.; Nasiri, A. [Atomic Energy Organization of Iran, Plasma and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute (Iran, Islamic Republic of)

    2017-01-15

    SORENA-1 is a very small repetitive Mather-type plasma focus device (20 J) that can operate at frequencies up to 1 Hz. This device has been designed and constructed in the Plasma and Nuclear Fusion Research School of the Nuclear Science and Technology Research Institute of Iran. In this article, the structure of SORENA-1 is described and results of experiments with Ar, Ne, and D{sub 2} working gases at several discharge voltages and initial pressures are presented and analyzed.

  3. Overcoming Challenges in Kinetic Modeling of Magnetized Plasmas and Vacuum Electronic Devices

    Science.gov (United States)

    Omelchenko, Yuri; Na, Dong-Yeop; Teixeira, Fernando

    2017-10-01

    We transform the state-of-the art of plasma modeling by taking advantage of novel computational techniques for fast and robust integration of multiscale hybrid (full particle ions, fluid electrons, no displacement current) and full-PIC models. These models are implemented in 3D HYPERS and axisymmetric full-PIC CONPIC codes. HYPERS is a massively parallel, asynchronous code. The HYPERS solver does not step fields and particles synchronously in time but instead executes local variable updates (events) at their self-adaptive rates while preserving fundamental conservation laws. The charge-conserving CONPIC code has a matrix-free explicit finite-element (FE) solver based on a sparse-approximate inverse (SPAI) algorithm. This explicit solver approximates the inverse FE system matrix (``mass'' matrix) using successive sparsity pattern orders of the original matrix. It does not reduce the set of Maxwell's equations to a vector-wave (curl-curl) equation of second order but instead utilizes the standard coupled first-order Maxwell's system. We discuss the ability of our codes to accurately and efficiently account for multiscale physical phenomena in 3D magnetized space and laboratory plasmas and axisymmetric vacuum electronic devices.

  4. Deploying Solid Targets in Dense Plasma Focus Devices for Improved Neutron Yields

    Science.gov (United States)

    Podpaly, Y. A.; Chapman, S.; Povilus, A.; Falabella, S.; Link, A.; Shaw, B. H.; Cooper, C. M.; Higginson, D.; Holod, I.; Sipe, N.; Gall, B.; Schmidt, A. E.

    2017-10-01

    We report on recent progress in using solid targets in dense plasma focus (DPF) devices. DPFs have been observed to generate energetic ion beams during the pinch phase; these beams interact with the dense plasma in the pinch region as well as the background gas and are believed to be the primary neutron generation mechanism for a D2 gas fill. Targets can be placed in the beam path to enhance neutron yield and to shorten the neutron pulse if desired. In this work, we measure yields from placing titanium deuteride foils, deuterated polyethylene, and non-deuterated control targets in deuterium filled DPFs at both megajoule and kilojoule scales. Furthermore, we have deployed beryllium targets in a helium gas-filled, kilojoule scale DPF for use as a potential AmBe radiological source replacement. Neutron yield, neutron time of flight, and optical images are used to diagnose the effectiveness of target deployments relative to particle-in-cell simulation predictions. A discussion of target holder engineering for material compatibility and damage control will be shown as well. Prepared by LLNL under Contract DE-AC52-07NA27344. Supported by the Office of Defense Nuclear Nonproliferation Research and Development within U.S. DOE's National Nuclear Security Administration and the LLNL Institutional Computing Grand Challenge program.

  5. Laser-driven, magnetized quasi-perpendicular collisionless shocks on the Large Plasma Device

    Energy Technology Data Exchange (ETDEWEB)

    Schaeffer, D. B., E-mail: dschaeffer@physics.ucla.edu; Everson, E. T.; Bondarenko, A. S.; Clark, S. E.; Constantin, C. G.; Vincena, S.; Van Compernolle, B.; Tripathi, S. K. P.; Gekelman, W.; Niemann, C. [Department of Physics and Astronomy, University of California - Los Angeles, Los Angeles, California 90095 (United States); Winske, D. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-05-15

    The interaction of a laser-driven super-Alfvénic magnetic piston with a large, preformed magnetized ambient plasma has been studied by utilizing a unique experimental platform that couples the Raptor kJ-class laser system [Niemann et al., J. Instrum. 7, P03010 (2012)] to the Large Plasma Device [Gekelman et al., Rev. Sci. Instrum. 62, 2875 (1991)] at the University of California, Los Angeles. This platform provides experimental conditions of relevance to space and astrophysical magnetic collisionless shocks and, in particular, allows a detailed study of the microphysics of shock formation, including piston-ambient ion collisionless coupling. An overview of the platform and its capabilities is given, and recent experimental results on the coupling of energy between piston and ambient ions and the formation of collisionless shocks are presented and compared to theoretical and computational work. In particular, a magnetosonic pulse consistent with a low-Mach number collisionless shock is observed in a quasi-perpendicular geometry in both experiments and simulations.

  6. Hybrid Synthetic Receptors on MOSFET Devices for Detection of Prostate Specific Antigen in Human Plasma.

    Science.gov (United States)

    Tamboli, Vibha K; Bhalla, Nikhil; Jolly, Pawan; Bowen, Chris R; Taylor, John T; Bowen, Jenna L; Allender, Chris J; Estrela, Pedro

    2016-12-06

    The study reports the use of extended gate field-effect transistors (FET) for the label-free and sensitive detection of prostate cancer (PCa) biomarkers in human plasma. The approach integrates for the first time hybrid synthetic receptors comprising of highly selective aptamer-lined pockets (apta-MIP) with FETs for sensitive detection of prostate specific antigen (PSA) at clinically relevant concentrations. The hybrid synthetic receptors were constructed by immobilizing an aptamer-PSA complex on gold and subjecting it to 13 cycles of dopamine electropolymerization. The polymerization resulted in the creation of highly selective polymeric cavities that retained the ability to recognize PSA post removal of the protein. The hybrid synthetic receptors were subsequently used in an extended gate FET setup for electrochemical detection of PSA. The sensor was reported to have a limit of detection of 0.1 pg/mL with a linear detection range from 0.1 pg/mL to 1 ng/mL PSA. Detection of 1-10 pg/mL PSA was also achieved in diluted human plasma. The present apta-MIP sensor developed in conjunction with FET devices demonstrates the potential for clinical application of synthetic hybrid receptors for the detection of clinically relevant biomarkers in complex samples.

  7. Considerações conceituais sobre Efficient Consumer Response (ECR no contexto supermercadista

    Directory of Open Access Journals (Sweden)

    Fabio Beylouni Lavratti

    2002-01-01

    Full Text Available Supermarket chains’ stock management is very defying when searching for cost reduction and increasing the consumer service level at the same time. There are three main ways: to store the materials in the back of the shopping unit, the use of distribution centers and the Efficient Consumer Response (ECR, which are non-exclusive alternatives that show different feasibility results for each particular problem. ECR is a retailer and producer collaborative management strategy used along the supply chain.

  8. Axial and radial preliminary results of the neutron radiation from miniature plasma focus devices

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, J.; Silva, P.; Soto, L. [Comision Chilena de Energia Nuclear, Santiago (Chile)

    2004-07-01

    As first step of a program to design a repetitive pulsed neutron generator for applications, two miniature plasma foci have been designed and constructed at the Chilean commission of nuclear energy. The devices operate at an energy level of the order of tens of joules (PF-50 J, 160 nF capacitor bank, 20-35 kV, 32-100 J, {approx} 150 ns time to peak current) and hundred of joules (PF-400 J, 880 nF, 20-35 kV, 176-539 J, {approx} 300 ns time to peak current). Neutron emission has been obtained in both devices operating in deuterium. A specific technique was necessary to develop in order to detect neutron pulsed of 10{sup 4} neutrons per shot. The maximum total neutron yield measured was of the order of 10{sup 6} and 10{sup 4} neutrons per shot in the PF-400 J and PF-50 J respectively. Axial and radial measurements of the neutron emission are presented and the anisotropy is evaluated in this work. The neutrons are measured by pairs of silver activation counters, {sup 3}He detectors and scintillator-photomultiplier detectors. (authors)

  9. Effect of anode shape on pinch structure and X-ray emission of plasma focus device

    Science.gov (United States)

    Talukdar, N.; Neog, N. K.; Borthkur, T. K.

    The effect of anode shapes on pinch structure and X-ray emission of plasma focus device operated with cylindrical, diverging, oval and converging anode tips is reported. The pinch structure in the radial compression phase has been investigated by employing a triple pinhole camera. It has been observed that pinch structure as well as the X-ray emission of PF device strongly depends upon anode tip designs. For the first time the studies were carried out in two new shapes of anode tips that is the oval and the divergent one. It has been observed that the oval and diverging anode tips are more conducive for the formation of instabilities and hotspot generation. The studies of X-ray emission were also carried out by employing three channels of a p-i-n diode X-ray spectrometer in entire anode designs to corroborate the results of a triple pinhole camera. Additionally, the effective hard X-ray photon energy was also estimated by the radiography method for all the anode tip designs, which indirectly provide a qualitative idea of the generation of induced accelerating field in the pinched column during compression.

  10. Inactivation of model viruses suspended in fresh frozen plasma using novel methylene blue based device.

    Science.gov (United States)

    Elikaei, Ameneh; Sharifi, Zohreh; Hosseini, Seyed Masoud; Latifi, Hamid; Musavi Hosseini, Mir Kamaran

    2014-02-01

    There is a concern on safety of human Fresh Frozen Plasma (FFP) as it is a source of some medicinal products. The possibility of transmission of blood-borne are reported often due to emerging viruses. There are some Pathogen Reduction Technologies (PRT) to inactivate viruses. Methylene Blue (MB) based method is one of them. The aim of this study was to examine new designated device to inactivate model viruses. Four model viruses were used in this study:Vesicular stomatitis virus (VSV), Herpes Simplex Virus I (HSV-1), Bovine Viral DiarrheaVirus(BVDV) and Polio Virus.50% Tissue Culture Infective Dose (TCID 50) and Reed-Muench Methods were used to titer the viruses. MB in two final concentration of 0.1 μM and 1 μM and illumination in about 627nm with red LED (Lamp Emitting Diode) for 15, 30, 45 and 60 minutes were used. Three replicates employed for each experiments. 1μMconcentration of MB showed more effective than 0.1μMin all designed illumination period for inactivation of HSV, VSV and BVDV. This method also demonstrated best results for enveloped model viruses. The most Log reduction for HSV, VSV and BVDV were6.28, 5.54 and 6.22, respectively. For HSV and BVDV inactivation, the best illumination period was 45 minutes. Model viruses showed sensitivity combination of MB and illumination using red LEDs. As results show this device could inactivate model viruses and reduce their titer very close to approved commercial devices, in compare.

  11. Status report of the ECR ion sources at the KVI

    CERN Document Server

    Drentje, A G; Kremers, H R; Meyer, D; Mulder, J; Sijbring, J

    1999-01-01

    At the moment three ECR ion sources are in operation at the KVI. One of these is being used as the ionizer section of the polarized ion (protons and deuterons) source POLIS; it runs at 2.5 GHz. In this paper the emphasis will be on the other two ECRISs, both being used for the production of highly charged ions. ECRIS3 is connected to the AGOR super-conducting Cyclotron. Beams of 12, 13C6+, 14N7+, 15N5+, 16O6+, 8+, 36Ar11+, 12+, 14+, 40Ar8+ and 3He2+, 4He2+ have been produced at various source voltages (16 - 29 kV), corresponding to a range of beam energies for experiments. The source is operating satisfactorily with sufficiently high beam intensities. Gas mixing is important for the high charge states of argon, where the best results have been obtained with 18O as a mixing gas. Since the AGOR cyclotron is used for the larger fraction of available beam time with (polarized) protons, the ECRIS3 set up is quite often available for test runs. ECRIS4 is connected to the five experimental set-ups of the Atomic Phys...

  12. Comparative study of radiation emission without and with target in a 2.2 kJ plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Muhammad Zubair, E-mail: mzubairkhan-um76@yahoo.com [Plasma Technology Research Center, Department of Physics, Faculty of Science, University Malaya, 50603 Kuala Lumpur Malaysia and Department of Physics, Federal Urdu University of Arts, Science and Technology, 45320 Islamabad (Pakistan); Ling, Yap Seong; San, Wong Chiow [Plasma Technology Research Center, Department of Physics, Faculty of Science, University Malaya, 50603 Kuala Lumpur (Malaysia)

    2014-03-24

    The radiation emission in a 2.2 kJ Mather-type dense plasma focus device is investigated using a five channel BPX65 PIN diode spectrometer. Estimated X-ray associated with the hollow anode without and with target in Argon gas medium is compared. At optimum conditions, the radiation emission from the system is found to be strongly influenced with target in hollow anode and the filling gas pressure. The maximum X-ray yield in 4π sr was obtained in case of hollow anode in argon gas medium with target 'Lead' due to interaction of electron beam. Results indicated that an appropriate design of hollow anode with target could enhance the radiation emission by more intense interaction of expected electron beam with target. The outcomes are helpful in designing a plasma focus with enhanced X-ray radiation with improved shot to shot reproducibility in plasma focus device.

  13. Proceedings of US/Japan workshop, Q219 on high heat flux components and plasma surface interactions for next fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Ulrickson, M.A.; Stevens, P.L.; Hino, T.; Hirohata, Y. [eds.

    1996-12-01

    This report contains the viewgraphs from the proceedings of US/Japan Workshop on High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices. Some of the general topics covered by this report are: PFC/PSI in tokamak and helical devices; development of high heat flux components; PSIS and plasma facing materials;tritium; and material damage.

  14. Selective Deposition of Multiple Sensing Materials on Si Nanobelt Devices through Plasma-Enhanced Chemical Vapor Deposition and Device-Localized Joule Heating.

    Science.gov (United States)

    Lin, Ru-Zheng; Cheng, Kuang-Yang; Pan, Fu-Ming; Sheu, Jeng-Tzong

    2017-11-22

    This paper describes a novel method, using device-localized Joule heating (JH) in a plasma enhanced atomic layer deposition (PEALD) system, for the selective deposition of platinum (Pt) and zinc oxide (ZnO) in the n- regions of n+/n-/n+ polysilicon nanobelts (SNBs). COMSOL simulations were adopted to estimate device temperature distribution. However, during ALD process, the resistance of SNB device decreased gradually and reached to minima after 20 min JH. As a result, thermal decomposition of precursors occurred during PEALD process. Selective deposition in the n- region was dominated by CVD instead of ALD. Selective deposition of Pt and ZnO films has been achieved and characterized using atomic force microscopy, scanning electron microscopy, and transmission electron microscopy.

  15. Integrated Prediction and Mitigation Methods of Materials Damage and Lifetime Assessment during Plasma Operation and Various Instabilities in Fusion Devices

    Energy Technology Data Exchange (ETDEWEB)

    Hassanein, Ahmed [Purdue Univ., West Lafayette, IN (United States)

    2015-03-31

    This report describes implementation of comprehensive and integrated models to evaluate plasma material interactions during normal and abnormal plasma operations. The models in full3D simulations represent state-of-the art worldwide development with numerous benchmarking of various tokamak devices and plasma simulators. In addition, significant number of experimental work has been performed in our center for materials under extreme environment (CMUXE) at Purdue to benchmark the effect of intense particle and heat fluxes on plasma-facing components. This represents one-year worth of work and resulted in more than 23 Journal Publications and numerous conferences presentations. The funding has helped several students to obtain their M.Sc. and Ph.D. degrees and many of them are now faculty members in US and around the world teaching and conducting fusion research. Our work has also been recognized through many awards.

  16. A new attempt using LabVIEW into a computational experiment of plasma focus device

    Science.gov (United States)

    Kim, Myungkyu

    2017-03-01

    The simulation program of plasma focus device based on S. Lee's model has been first developed since 30 years ago and it is widely used to date. Originally the program made by GWbasic language, and then modified by visual basic which was included in the Microsoft Excel. Using Excel well-known to researchers is a key advantage of this program. But it has disadvantages in displaying data in same graph, in slow calculation speed, and in displaying data and calculation of smaller time step. To overcome all these points, the LabVIEW that made by national instrument and based on graphical environment is used for simulation. Furthermore it is correlated with data acquisition of experiment, once experiment being the data is directly transferred to the simulation program and then analyzes and predicts for the next shot. The mass swept factor (fm) and current factor (fc) can be easily find out using this program. This paper describes the detail function and usage of the program and compares the results with the existing one.

  17. The pyrolytic-plasma method and the device for the utilization of hazardous waste containing organic compounds.

    Science.gov (United States)

    Opalińska, Teresa; Wnęk, Bartłomiej; Witowski, Artur; Juszczuk, Rafał; Majdak, Małgorzata; Bartusek, Stanilav

    2016-11-15

    This paper is focused on the new method of waste processing. The waste, including hazardous waste, contain organic compounds. The method consists in two main processes: the pyrolysis of waste and the oxidation of the pyrolytic gas with a use of non-equilibrium plasma. The practical implementation of the method requires the design, construction and testing of the new device in large laboratory scale. The experiments were carried out for the two kinds of waste: polyethylene as a model waste and the electronic waste as a real waste. The process of polyethylene decomposition showed that the operation of the device is correct because 99.74% of carbon moles contained in the PE samples was detected in the gas after the process. Thus, the PE samples practically were pyrolyzed completely to hydrocarbons, which were completely oxidized in the plasma reactor. It turned out that the device is useful for decomposition of the electronic waste. The conditions in the plasma reactor during the oxidation process of the pyrolysis products did not promote the formation of PCDD/Fs despite the presence of the oxidizing conditions. An important parameter determining the efficiency of the oxidation of the pyrolysis products is gas temperature in the plasma reactor. Copyright © 2016 The Author(s). Published by Elsevier B.V. All rights reserved.

  18. Magnetic shield for turbomolecular pump of the Magnetized Plasma Linear Experimental device at Saha Institute of Nuclear Physics.

    Science.gov (United States)

    Biswas, Subir; Chattopadhyay, Monobir; Pal, Rabindranath

    2011-01-01

    The turbo molecular pump of the Magnetized Plasma Linear Experimental device is protected from damage by a magnetic shield. As the pump runs continuously in a magnetic field environment during a plasma physics experiment, it may get damaged owing to eddy current effect. For design and testing of the shield, first we simulate in details various aspects of magnetic shield layouts using a readily available field design code. The performance of the shield made from two half cylinders of soft iron material, is experimentally observed to agree very well with the simulation results.

  19. Development of a double plasma gun device for investigation of effects of vapor shielding on erosion of PFC materials under ELM-like pulsed plasma bombardment

    Science.gov (United States)

    Sakuma, I.; Iwamoto, D.; Kitagawa, Y.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

    2012-10-01

    It is considered that thermal transient events such as type I edge localized modes (ELMs) could limit the lifetime of plasma-facing components (PFCs) in ITER. We have investigated surface damage of tungsten (W) materials under transient heat and particle loads by using a magnetized coaxial plasma gun (MCPG) device at University of Hyogo. The capacitor bank energy for the plasma discharge is 144 kJ (2.88 mF, 10 kVmax). Surface melting of a W material was clearly observed at the energy density of ˜2 MJ/m2. It is known that surface melting and evaporation during a transient heat load could generate a vapor cloud layer in front of the target material [1]. Then, the subsequent erosion could be reduced by the vapor shielding effect. In this study, we introduce a new experiment using two MCPG devices (MCPG-1, 2) to understand vapor shielding effects of a W surface under ELM-like pulsed plasma bombardment. The capacitor bank energy of MCPG-2 is almost same as that of MCPG-1. The second plasmoid is applied with a variable delay time after the plasmoid produced by MCPG-1. Then, a vapor cloud layer could shield the second plasma load. To verify the vapor shielding effects, surface damage of a W material is investigated by changing the delay time. In the conference, the preliminary experimental results will be shown.[4pt] [1] A. Hassanein et al., J. Nucl. Mater. 390-391, pp. 777-780 (2009).

  20. ECR Browser: A Tool For Visualizing And Accessing Data From Comparisons Of Multiple Vertebrate Genomes

    Energy Technology Data Exchange (ETDEWEB)

    Loots, G G; Ovcharenko, I; Stubbs, L; Nobrega, M A

    2004-01-06

    The increasing number of vertebrate genomes being sequenced in draft or finished form provide a unique opportunity to study and decode the language of DNA sequence through comparative genome alignments. However, novel tools and strategies are required to accommodate this increasing volume of genomic information and to facilitate experimental annotation of genome function. Here we present the ECR Browser, a tool that provides an easy and dynamic access to whole genome alignments of human, mouse, rat and fish sequences. This web-based tool (http://ecrbrowser.dcode.org) provides the starting point for discovery of novel genes, identification of distant gene regulatory elements and prediction of transcription factor binding sites. The genome alignment portal of the ECR Browser also permits fast and automated alignment of any user-submitted sequence to the genome of choice. The interconnection of the ECR browser with other DNA sequence analysis tools creates a unique portal for studying and exploring vertebrate genomes.

  1. Simulation study of LEBT for transversely coupled beam from an ECR ion source.

    Science.gov (United States)

    Yang, Y; Dou, W P; Sun, L T; Yao, Q G; Zhang, Z M; Yuan, Y J; He, Y; Zh, X Z; Zhao, H W

    2016-02-01

    A Low-Energy intense-highly charged ion Accelerator Facility (LEAF) program has been launched at Institute of Modern Physics. This accelerator facility consists of a superconducting Electron Cyclotron Resonance (ECR) ion source, a Low Energy Beam Transport (LEBT) system, and a Radio Frequency Quadrupole (RFQ). It is especially of interest for the extracted ion beam from the ECR ion source, which is transversely coupled, and this property will significantly affect the beam transmission in the LEBT line and the matching with the downstream RFQ. In the beam transport design of LEAF, beam decoupling in the LEBT is considered to lower down the projection emittances and the feasibility of the design has been verified by beam simulation with a transversely coupled beam from the ECR ion source.

  2. Microwave transmission efficiency and simulations of electron plasma in ELTRAP device

    Science.gov (United States)

    Ikram, M.; Mushtaq, A.; Ali, S.

    2017-11-01

    A Thomson backscattering experiment has been performed in a Penning-Malmberg device ELTRAP. To estimate the minimum sensitivity of diagnostics, we have computed the signal to noise ratio and found that the present bunch has a number density of 4.3 × 108 cm-3, which is three orders of magnitude less than the desired density of 1011 cm-3. To increase the signal level from the RF studies to the GHz range, the transmission efficiency from the rectangular waveguide orthogonally coupled to a prototype circular waveguide was experimentally analyzed on a test-bench. It is observed that the lengths of waveguides play an important role in the transmission efficiency and return loss. When the length of the optimum rectangular waveguide (>2 λg = 31 cm) is reduced to 7 cm, due to geometrical constraints of the ELTRAP device, consequently, the transmission efficiency is also reduced and shifts away from the maximum 3 GHz operating frequency. The useful frequency band is then reduced with the increasing length of the prototype circular waveguide (102 cm). Using the electromagnetic Particle-In-Cell simulations involving the electron cyclotron resonance heating (ECRH), we have utilized a magnetic field of 0.1 T resonating with 2.8 GHz RF drive during each time step (1 ps) having the power level of 0.04 V to the middle and to the end of the trap. A more efficient increase in the radial and azimuthal temperature profiles is observed as compared to the axial temperature profile. The reason is the use of ECRH to heat electrons in cyclotron motion, which is completely kinetic and magnetron motion which is almost entirely potential based. The axial motion interchanges in between the kinetic and potential with a slight enhancement in axial motion to maintain the total canonical angular momentum conserved. The temperature profile of the confined electron plasma increases with the variation of densities from 5 × 107 m-3 to 1012 m-3. The major heating effect occurs when the RF power is

  3. Miniature plasma focus as a novel device for synthesis of soft magnetic FeCo thin films

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Z.Y. [NSSE, National Institute of Education, Nanyang Technological University, 1 Nanyang walk, Singapore 637616 (Singapore); Rawat, R.S., E-mail: rajdeep.rawat@nie.edu.s [NSSE, National Institute of Education, Nanyang Technological University, 1 Nanyang walk, Singapore 637616 (Singapore); Verma, R. [NSSE, National Institute of Education, Nanyang Technological University, 1 Nanyang walk, Singapore 637616 (Singapore); Pulsed Power Group, Institute for Plasma Research, Bhat, Gandhinagar, Gujarat, India 382428 (India); Lin, J.J. [Solar Energy Research Institute of Singapore, National University of Singapore, 7 Engineering Drive 1, Singapore 117574 (Singapore); Yan, H.; Ramanujan, R.V. [School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore); Lee, P.; Springham, S.V.; Tan, T.L. [NSSE, National Institute of Education, Nanyang Technological University, 1 Nanyang walk, Singapore 637616 (Singapore)

    2010-02-08

    The Letter reports the first ever application of low energy miniature plasma focus device as a deposition facility for nanostructured thin films. We demonstrate successful utilization of a 120 J fast miniature plasma focus device as a novel facility for the deposition of magnetically soft FeCo thin films. Different gas types and the substrate materials were used to investigate their effects on magnetic properties of the films. The FeCo films deposited on Si{sub (100)} with hydrogen as the filling gas were found to have an average grain size of 10.8+-1.2 nm with narrow size distribution and soft magnetic properties with coercivity of about 6.3 Oe. The experimental coercivity value matched reasonably well with the theoretical calculation done using ripple theory.

  4. Plasma Sputtering Robotic Device for In-Situ Thick Coatings of Long, Small Diameter Vacuum Tubes

    Science.gov (United States)

    Hershcovitch, Ady

    2014-10-01

    A novel robotic plasma magnetron mole with a 50 cm long cathode was designed fabricated & operated. Reason for this endeavor is to alleviate the problems of unacceptable ohmic heating of stainless steel vacuum tubes and of electron clouds, due to high secondary electron yield (SEY), in the BNL Relativistic Heavy Ion Collider (RHIC). The magnetron mole was successfully operated to copper coat an assembly containing a full-size, stainless steel, cold bore, RHIC magnet tubing connected to two types of RHIC bellows, to which two additional pipes made of RHIC tubing were connected. To increase cathode lifetime, movable magnet package was developed, and thickest possible cathode was made, with a rather challenging target to substrate (de facto anode) distance of less than 1.5 cm. Achieving reliable steady state magnetron discharges at such a short cathode to anode gap was rather challenging, when compared to commercial coating equipment, where the target to substrate distance is 10's cm; 6.3 cm is the lowest experimental target to substrate distance found in the literature. Additionally, the magnetron developed during this project provides unique omni-directional uniform coating. The magnetron is mounted on a carriage with spring loaded wheels that successfully crossed bellows and adjusted for variations in vacuum tube diameter, while keeping the magnetron centered. Electrical power and cooling water were fed through a cable bundle. The umbilical cabling system is driven by a motorized spool. Excellent coating adhesion was achieved. Measurements indicated that well-scrubbed copper coating reduced SEY to 1, i.e., the problem of electron clouds can be eliminated. Room temperature RF resistivity measurement indicated that 10 μm Cu coated stainless steel RHIC tube has conductivity close to that of pure copper tubing. Excellent coating adhesion was achieved. Device detail and experimental results will be presented. Work supported by Brookhaven Science Associates, LLC under

  5. Plasma sputtering robotic device for in-situ thick coatings of long, small diameter vacuum tubesa)

    Science.gov (United States)

    Hershcovitch, A.; Blaskiewicz, M.; Brennan, J. M.; Custer, A.; Dingus, A.; Erickson, M.; Fischer, W.; Jamshidi, N.; Laping, R.; Liaw, C.-J.; Meng, W.; Poole, H. J.; Todd, R.

    2015-05-01

    A novel robotic plasma magnetron mole with a 50 cm long cathode was designed, fabricated, and operated. The reason for this endeavor is to alleviate the problems of unacceptable resistive heating of stainless steel vacuum tubes in the BNL Relativistic Heavy Ion Collider (RHIC). The magnetron mole was successfully operated to copper coat an assembly containing a full-size, stainless steel, cold bore, RHIC magnet tubing connected to two types of RHIC bellows, to which two additional pipes made of RHIC tubing were connected. To increase the cathode lifetime, a movable magnet package was developed, and the thickest possible cathode was made, with a rather challenging target to substrate (de facto anode) distance of less than 1.5 cm. Achieving reliable steady state magnetron discharges at such a short cathode to anode gap was rather challenging, when compared to commercial coating equipment, where the target to substrate distance is 10's cm; 6.3 cm is the lowest experimental target to substrate distance found in the literature. Additionally, the magnetron developed during this project provides unique omni-directional uniform coating. The magnetron is mounted on a carriage with spring loaded wheels that successfully crossed bellows and adjusted for variations in vacuum tube diameter, while keeping the magnetron centered. Electrical power and cooling water were fed through a cable bundle. The umbilical cabling system is driven by a motorized spool. Excellent coating adhesion was achieved. Measurements indicated that well-scrubbed copper coating reduced secondary electron yield to 1, i.e., the problem of electron clouds can be eliminated. Room temperature RF resistivity measurement indicated that a 10 μm copper coated stainless steel RHIC tube has a conductivity close to that of pure copper tubing. Excellent coating adhesion was achieved. The device details and experimental results are described.

  6. Ecdysone Receptor (EcR Is Involved in the Transcription of Cell Cycle Genes in the Silkworm

    Directory of Open Access Journals (Sweden)

    Wenliang Qian

    2015-02-01

    Full Text Available EcR (ecdysone receptor-mediated ecdysone signaling pathway contributes to regulate the transcription of genes involved in various processes during insect development. In this work, we detected the expression of EcR gene in silkworm ovary-derived BmN4 cells and found that EcR RNAi result in an alteration of cell shape, indicating that EcR may orchestrate cell cycle progression. EcR RNAi and EcR overexpression analysis revealed that in the cultured BmN4 cells, EcR respectively promoted and suppressed the transcription of E2F-1 and CycE, two genes controlling cell cycle progression. Further examination demonstrated that ecdysone application in BmN4 cells not only changed the transcription of these two cell cycle genes like that under EcR overexpression, but also induced cell cycle arrest at G2/M phase. In vivo analysis confirmed that E2F-1 expression was elevated in silk gland of silkworm larvae after ecdysone application, which is same as its response to ecdysone in BmN4 cells. However, ecdysone also promotes CycE transcription in silk gland, and this is converse with the observation in BmN4 cells. These results provide new insights into understanding the roles of EcR-mediated ecdysone signaling in the regulation of cell cycle.

  7. Demonstration of neutron production in a table-top pinch plasma focus device operating at only tens of joules

    Energy Technology Data Exchange (ETDEWEB)

    Soto, Leopoldo; Silva, Patricio; Moreno, Jose; Zambra, Marcelo; Pavez, Cristian [Comision Chilena de EnergIa Nuclear, Casilla 188-D, Santiago (Chile); Kies, Walter; Altamirano, Luis; Huerta, Luis [Center for Research and Applications in Plasma Physics and Pulsed Power, P4 (Chile); Mayer, Roberto E [Centro Atomico Bariloche and Instituto Balseiro, 8400 Bariloche (Argentina); Clausse, Alejandro [CNEA-CONICET and Universidad Nacional del Centro, 7000 Tandil (Argentina)], E-mail: lsoto@cchen.cl

    2008-10-21

    Neutron emission from a deuterium plasma pinch generated in a very small plasma focus (6 mm anode diameter) operating at only tens of joules is presented. A maximum current of 50 kA is achieved 140 ns after the beginning of the discharge, when the device is charged at 50 J (160 nF capacitor bank, 38 nH, 20-30 kV, 32-72 J). Although the stored energy is very low, the estimated energy density in the plasma and the energy per particle in the plasma are of the same order as in higher energy devices. The dependence of the neutron yield on the filling pressure of deuterium was obtained for discharges with 50 and 67 J stored in the capacitor bank. Neutrons were measured by means of a system based on a {sup 3}He proportional counter in current mode. The average neutron yield for 50 J discharges at 6 mbar was (1.2 {+-} 0.5) x 10{sup 4} neutrons per shot, and (3.6 {+-} 1.6) x 10{sup 4} for 67 J discharges at 9 mbar. The maximum energy of the neutrons was (2.7 {+-} 1.8) MeV. Possible applications related to substance detection and others are discussed.

  8. Evidence of nuclear fusion neutrons in an extremely small plasma focus device operating at 0.1 Joules

    Science.gov (United States)

    Soto, Leopoldo; Pavéz, Cristián; Moreno, José; Altamirano, Luis; Huerta, Luis; Barbaglia, Mario; Clausse, Alejandro; Mayer, Roberto E.

    2017-08-01

    We report on D-D fusion neutron emission in a plasma device with an energy input of only 0.1 J, within a range where fusion events have been considered very improbable. The results presented here are the consequence of scaling rules we have derived, thus being the key point to assure the same energy density plasma in smaller devices than in large machines. The Nanofocus (NF)—our device—was designed and constructed at the P4 Lab of the Chilean Nuclear Energy Commission. Two sets of independent measurements, with different instrumentation, were made at two laboratories, in Chile and Argentina. The neutron events observed are 20σ greater than the background. The NF plasma is produced from a pulsed electrical discharge using a submillimetric anode, in a deuterium atmosphere, showing empirically that it is, in fact, possible to heat and compress the plasma. The strong evidence presented here stretches the limits beyond what was expected. A thorough understanding of this could possibly tell us where the theoretical limits actually lie, beyond conjectures. Notwithstanding, a window is thus open for low cost endeavours for basic fusion research. In addition, the development of small, portable, safe nonradioactive neutron sources becomes a feasible issue.

  9. Modelling of plasma-wall interaction and impurity transport in fusion devices and prompt deposition of tungsten as application

    Science.gov (United States)

    Kirschner, A.; Tskhakaya, D.; Brezinsek, S.; Borodin, D.; Romazanov, J.; Ding, R.; Eksaeva, A.; Linsmeier, Ch

    2018-01-01

    Main processes of plasma-wall interaction and impurity transport in fusion devices and their impact on the availability of the devices are presented and modelling tools, in particular the three-dimensional Monte-Carlo code ERO, are introduced. The capability of ERO is demonstrated on the example of tungsten erosion and deposition modelling. The dependence of tungsten deposition on plasma temperature and density is studied by simulations with a simplified geometry assuming (almost) constant plasma parameters. The amount of deposition increases with increasing electron temperature and density. Up to 100% of eroded tungsten can be promptly deposited near to the location of erosion at very high densities (∼1 × 1014 cm‑3 expected e.g. in the divertor of ITER). The effect of the sheath characteristics on tungsten prompt deposition is investigated by using particle-in-cell (PIC) simulations to spatially resolve the plasma parameters inside the sheath. Applying PIC data instead of non-resolved sheath leads in general to smaller tungsten deposition, which is mainly due to a density and temperature decrease towards the surface within the sheath. Two-dimensional tungsten erosion/deposition simulations, assuming symmetry in toroidal direction but poloidally spatially varying plasma parameter profiles, have been carried out for the JET divertor. The simulations reveal, similar to experimental findings, that tungsten gross erosion is dominated in H-mode plasmas by the intra-ELM phases. However, due to deposition, the net tungsten erosion can be similar within intra- and inter-ELM phases if the inter-ELM electron temperature is high enough. Also, the simulated deposition fraction of about 84% in between ELMs is in line with spectroscopic observations from which a lower limit of 50% has been estimated.

  10. Physical processes taking place in dense plasma focus devices at the interaction of hot plasma and fast ion streams with materials under test

    Science.gov (United States)

    Gribkov, V. A.

    2015-06-01

    The dense plasma focus (DPF) device represents a source of powerful streams of penetrating radiations (hot plasma, fast electron and ion beams, x-rays and neutrons) of ns-scale pulse durations. Power flux densities of the radiation types may reach in certain cases the values up to 1013 W cm  -  2. They are widely used at present time in more than 30 labs in the world in the field of radiation material science. Areas of their implementations are testing of the materials perspective for use in modern fusion reactors (FR) of both types, modification of surface layers with an aim of improvements their properties, production of some nanostructures on their surface, and so on. To use a DPF correctly in these applications it is important to understand the mechanisms of generation of the above-mentioned radiations, their dynamics inside and outside of the pinch and processes of interaction of these streams with targets. In this paper, the most important issues on the above matter we discuss in relation to the cumulative hot plasma stream and the beam of fast ions with illustration of experimental results obtained at four DPF devices ranged in the limits of bank energies from 1 kJ to 1 MJ. Among them mechanisms of a jet formation, a current abruption phenomenon, a super-Alfven ion beam propagation inside and outside of DPF plasma, generation of secondary plasma and formation of shock waves in plasma and inside a solid-state target, etc. Nanosecond time-resolved techniques (electric probes, laser interferometry, frame self-luminescent imaging, x-ray/neutron probes, etc) give an opportunity to investigate the above-mentioned events and to observe the process of interaction of the radiation types with targets. After irradiation, we analyzed the specimens by contemporary instrumentation: optical and scanning electron microscopy, local x-ray spectral and structure analysis, atomic force microscopy, the portable x-ray diffractometer that combines x-ray single

  11. Plasma-Material Interface Development for Future Spherical Tokamak-based Devices in NSTX.

    Energy Technology Data Exchange (ETDEWEB)

    et. al, V

    2011-09-24

    , ELMs otherwise suppressed due to lithium conditioning. Fast divertor measurements showed that impulsive particle and heat fluxes due to the ELMs were significantly dissipated in the high magnetic flux expansion region of the snowflake divertor. The snowflake divertor configuration is being combined in experiments with extrinsic deuterium or impurity gas puffing for increased dissipative divertor power losses, additional upper divertor nulls for increased power sharing between the upper and the lower divertors, and lithium coated plasma facing components for large area ion pumping. These efforts are aimed at the development of an integrated PMI for future ST-based devices for fusion development applications.

  12. Method and device for reducing overpenetration at the start of plasma arc welds

    Science.gov (United States)

    Sanders, John M.; Lehmann, John M.; Ryan, Patrick M.

    1998-01-01

    A shim for improving plasma arc weld quality has ends tapered at about 25.degree. and notches at each end roughly centered over the corner between the tapered ends and main body of the shim. The improved shim allows lower starting plasma arc heat input and reduces the occurrence of sagging, or overpenetration, of the weld.

  13. An in situ accelerator-based diagnostic for plasma-material interactions science on magnetic fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Hartwig, Zachary S.; Barnard, Harold S.; Lanza, Richard C.; Sorbom, Brandon N.; Stahle, Peter W.; Whyte, Dennis G. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge Massachusetts 02139 (United States)

    2013-12-15

    This paper presents a novel particle accelerator-based diagnostic that nondestructively measures the evolution of material surface compositions inside magnetic fusion devices. The diagnostic's purpose is to contribute to an integrated understanding of plasma-material interactions in magnetic fusion, which is severely hindered by a dearth of in situ material surface diagnosis. The diagnostic aims to remotely generate isotopic concentration maps on a plasma shot-to-shot timescale that cover a large fraction of the plasma-facing surface inside of a magnetic fusion device without the need for vacuum breaks or physical access to the material surfaces. Our instrument uses a compact (∼1 m), high-current (∼1 milliamp) radio-frequency quadrupole accelerator to inject 0.9 MeV deuterons into the Alcator C-Mod tokamak at MIT. We control the tokamak magnetic fields – in between plasma shots – to steer the deuterons to material surfaces where the deuterons cause high-Q nuclear reactions with low-Z isotopes ∼5 μm into the material. The induced neutrons and gamma rays are measured with scintillation detectors; energy spectra analysis provides quantitative reconstruction of surface compositions. An overview of the diagnostic technique, known as accelerator-based in situ materials surveillance (AIMS), and the first AIMS diagnostic on the Alcator C-Mod tokamak is given. Experimental validation is shown to demonstrate that an optimized deuteron beam is injected into the tokamak, that low-Z isotopes such as deuterium and boron can be quantified on the material surfaces, and that magnetic steering provides access to different measurement locations. The first AIMS analysis, which measures the relative change in deuterium at a single surface location at the end of the Alcator C-Mod FY2012 plasma campaign, is also presented.

  14. An in situ accelerator-based diagnostic for plasma-material interactions science on magnetic fusion devices.

    Science.gov (United States)

    Hartwig, Zachary S; Barnard, Harold S; Lanza, Richard C; Sorbom, Brandon N; Stahle, Peter W; Whyte, Dennis G

    2013-12-01

    This paper presents a novel particle accelerator-based diagnostic that nondestructively measures the evolution of material surface compositions inside magnetic fusion devices. The diagnostic's purpose is to contribute to an integrated understanding of plasma-material interactions in magnetic fusion, which is severely hindered by a dearth of in situ material surface diagnosis. The diagnostic aims to remotely generate isotopic concentration maps on a plasma shot-to-shot timescale that cover a large fraction of the plasma-facing surface inside of a magnetic fusion device without the need for vacuum breaks or physical access to the material surfaces. Our instrument uses a compact (~1 m), high-current (~1 milliamp) radio-frequency quadrupole accelerator to inject 0.9 MeV deuterons into the Alcator C-Mod tokamak at MIT. We control the tokamak magnetic fields--in between plasma shots--to steer the deuterons to material surfaces where the deuterons cause high-Q nuclear reactions with low-Z isotopes ~5 μm into the material. The induced neutrons and gamma rays are measured with scintillation detectors; energy spectra analysis provides quantitative reconstruction of surface compositions. An overview of the diagnostic technique, known as accelerator-based in situ materials surveillance (AIMS), and the first AIMS diagnostic on the Alcator C-Mod tokamak is given. Experimental validation is shown to demonstrate that an optimized deuteron beam is injected into the tokamak, that low-Z isotopes such as deuterium and boron can be quantified on the material surfaces, and that magnetic steering provides access to different measurement locations. The first AIMS analysis, which measures the relative change in deuterium at a single surface location at the end of the Alcator C-Mod FY2012 plasma campaign, is also presented.

  15. Tornado type closed magnetic trap for an ECR source

    CERN Document Server

    Abramova, K B; Voronin, A V; Zorin, V G

    1999-01-01

    We propose to use a Tornado type closed magnetic trap for creation of a source of mul-ticharged ions with plasma heating by microwave radiation. Plasma loss in closed traps is deter-mined by diffusion across the magnetic field, which increases substantially plasma confinement time as compared to the classical mirror trap [1]. We propose to extract ions with the aid of additional coils which partially destroy the closed structure of the magnetic lines in the trap, but don not influence the total confinement time. This allows for producing a controlled plasma flux that depends on the magnetic field of the additional coil. The Tornado trap also possesses merits such as an opportunity to produce high magnetic fields up to 3 T, which makes possible heating and confinement of plasma with a high density of electrons; plasma stability to magneto-hydrodynamic perturbations because the magnetic field structure corresponds to the "min B" configuration; and relatively low costs. All estimates and calculations were carrie...

  16. Evidências de validade do Experience in Close Relationships (ECR Inventory para o Brasil

    Directory of Open Access Journals (Sweden)

    Victor Kenji Medeiros Shiramizu

    2013-09-01

    Full Text Available Instrumentos que aferem apego adulto fundamentam-se na noção de que os padrões de vinculação estabelecidos na primeira infância transpõem-se para relacionamentos amorosos na vida adulta. O objetivo desta pesquisa foi buscar evidências de validade de um instrumento para aferir apego adulto, traduzido e adaptado para o Brasil: Experience in Close Relationships Inventory (ECR. Para tanto, realizaram-se dois estudos consecutivos. No primeiro, traduziu-se o ECR e aplicou-se em 230 estudantes universitários. A partir dos resultados, modificaram-se itens e aplicou-se a escala em uma amostra de 618 pessoas das cinco regiões do Brasil. Os resultados indicaram uma estrutura bidimensional, ansiedade e evitação relacionada ao apego, para o ECR-Brasil, bem como, adequados índices de precisão. Encontraram-se correlações consonantes com a teoria do construto para as duas dimensões avaliadas, níveis de amor e sociossexualidade. O instrumento também diferenciou pessoas em relacionamento compromissado e não compromissado. Considera-se que ECR-Brasil mostrou satisfatórias evidências de validade e precisão.

  17. Beam simulation studies of ECR beam extraction and low energy beam transport for FRIB.

    Science.gov (United States)

    Ren, Haitao; Pozdeyev, Eduard; Lund, Steven M; Machicoane, Guillaume; Wu, Xiaoyu; Morgan, Glenn

    2016-02-01

    To meet the beam power requirements of 400 kW at the fragmentation target for facility for Rare Isotope Beams (FRIB), simultaneous acceleration of two-charge states should be used for heavier ions. These intense multi-charged ion beams will be produced by a 28 GHz electron cyclotron resonance (ECR) ion source at a high voltage of 35 kV. After extraction, the ion beam will be pre-accelerated to 12 keV/u with a 50 kV platform, transported down to an achromatic charge state selection (CSS) system followed by a vertical transport line, and then injected into a radio frequency quadrupole accelerator. The TRACK code developed at ANL is used to perform the simulations of the ECR beam extraction and low energy beam transport for FRIB. In this study, we include the magnetic field of ECR ion source into simulations. Different initial beam conditions as well as different space charge neutralization levels are tested for the ECR beamline. The beam loss in CSS system and the corresponding protective measures are discussed. The detailed results about the beam dynamic simulation and beam loss in CSS system will be presented in this paper.

  18. Unstable plasma characteristics in mirror field electron cyclotron ...

    Indian Academy of Sciences (India)

    Electron cyclotron plasma reactor are prone to instabilities in specific input power [3–. 7] region (150–450 watts). ... Electron cyclotron resonance (ECR) plasma technology has become very important for fabrication of very large scale ... left hand polarized (LHP) wave. Shufflbotham and Thomson [4] observed several distinct.

  19. Isolation of Circulating Plasma Cells in Multiple Myeloma Using CD138 Antibody-Based Capture in a Microfluidic Device

    Science.gov (United States)

    Qasaimeh, Mohammad A.; Wu, Yichao C.; Bose, Suman; Menachery, Anoop; Talluri, Srikanth; Gonzalez, Gabriel; Fulciniti, Mariateresa; Karp, Jeffrey M.; Prabhala, Rao H.; Karnik, Rohit

    2017-04-01

    The necessity for bone marrow aspiration and the lack of highly sensitive assays to detect residual disease present challenges for effective management of multiple myeloma (MM), a plasma cell cancer. We show that a microfluidic cell capture based on CD138 antigen, which is highly expressed on plasma cells, permits quantitation of rare circulating plasma cells (CPCs) in blood and subsequent fluorescence-based assays. The microfluidic device is based on a herringbone channel design, and exhibits an estimated cell capture efficiency of ~40-70%, permitting detection of numbers in blood samples of MM patients in remission (20-24 CD138+ cells/mL), and yet higher numbers in MM patients exhibiting disease (45-184 CD138+ cells/mL). Analysis of CPCs isolated using the device was consistent with serum immunoglobulin assays that are commonly used in MM diagnostics. These results indicate the potential of CD138-based microfluidic CPC capture as a useful ‘liquid biopsy’ that may complement or partially replace bone marrow aspiration.

  20. Safety of plasma-based sterilization: surface modifications of polymeric medical devices induced by Sterrad and Plazlyte processes.

    Science.gov (United States)

    Lerouge, S; Tabrizian, M; Wertheimer, M R; Marchand, R; Yahia, L'H

    2002-01-01

    Plasma-based sterilization is a promising alternative to the use of pure ethylene oxide (EO), for low-temperature clinical sterilization of medical instruments and devices. However, few studies have been published that evaluate its safety in terms of possible damage to materials, particularly polymers. The objective of this work was to evaluate polymer surface modifications induced by commercial plasma-based sterilizers, in comparison with pure EO: Samples from 5 polymer-based devices were subjected to 1, 5, and 10 sterilization cycles by Sterrad-100, Plazlyte, and pure EO. Surface analysis was carried out by X-ray photoelectron spectroscopy (XPS), dynamic contact angle measurements (DCA), and scanning electron microscopy (SEM). Surface oxidation and wettability changes were observed on all samples sterilized by plasma-based techniques, the degree of modifications depending on the sterilizer (Sterrad, Plazlyte) and the type of polymer. Drastic changes of surface appearance were also observed by SEM on PVC samples sterilized by Plazlyte and by pure EO. Possible repercussions on safety are discussed.

  1. Three-dimensional tomographic imaging for dynamic radiation behavior study using infrared imaging video bolometers in large helical device plasma

    Energy Technology Data Exchange (ETDEWEB)

    Sano, Ryuichi; Iwama, Naofumi [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); Peterson, Byron J.; Kobayashi, Masahiro; Mukai, Kiyofumi [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); SOKENDAI (The Graduate University for Advanced Studies), Hayama, Kanagawa 240-0193 (Japan); Teranishi, Masaru [Hiroshima Institute of Technology, 2-1-1, Miyake, Saeki-ku, Hiroshima 731-5193 (Japan); Pandya, Shwetang N. [Institute of Plasma Research, Near Indira Bridge, Bhat Village, Gandhinagar, Gujarat 382428 (India)

    2016-05-15

    A three-dimensional (3D) tomography system using four InfraRed imaging Video Bolometers (IRVBs) has been designed with a helical periodicity assumption for the purpose of plasma radiation measurement in the large helical device. For the spatial inversion of large sized arrays, the system has been numerically and experimentally examined using the Tikhonov regularization with the criterion of minimum generalized cross validation, which is the standard solver of inverse problems. The 3D transport code EMC3-EIRENE for impurity behavior and related radiation has been used to produce phantoms for numerical tests, and the relative calibration of the IRVB images has been carried out with a simple function model of the decaying plasma in a radiation collapse. The tomography system can respond to temporal changes in the plasma profile and identify the 3D dynamic behavior of radiation, such as the radiation enhancement that starts from the inboard side of the torus, during the radiation collapse. The reconstruction results are also consistent with the output signals of a resistive bolometer. These results indicate that the designed 3D tomography system is available for the 3D imaging of radiation. The first 3D direct tomographic measurement of a magnetically confined plasma has been achieved.

  2. Ammonia formation and W coatings interaction with deuterium/nitrogen plasmas in the linear device GyM

    Energy Technology Data Exchange (ETDEWEB)

    Laguardia, L., E-mail: laguardia@ifp.cnr.it [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy); Caniello, R.; Cremona, A. [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy); Dellasega, D. [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy); Politecnico di Milano, Dipartimento di Energia, Milan (Italy); Dell’Era, F.; Ghezzi, F.; Gittini, G.; Granucci, G.; Mellera, V.; Minelli, D.; Pallotta, F. [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy); Passoni, M. [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy); Politecnico di Milano, Dipartimento di Energia, Milan (Italy); Ricci, D.; Vassallo, E. [CNR, Istituto di Fisica del Plasma“P. Caldirola”, Milan (Italy)

    2015-08-15

    In this work results of the first D{sub 2}/N{sub 2} experiments in GyM, a linear device able to produce plasmas of interest for the ITER divertor (n{sub e} 5 ⋅ 10{sup 10} cm{sup −3}, Te 5 eV, ion flux 3–5 ⋅ 10{sup 20} m{sup −2}s{sup −1}) are presented. Plasmas simulating a N-seeding scenario have been performed to evaluate ammonia formation and its effect on exposed W coatings. The presence of ND emission lines in the plasma can be correlated with the formation of ammonia, further directly detected and quantified by chromatography analysis of the exhaust. Four different W specimens were exposed in GyM to a plasma fluence of 8.78 ⋅ 10{sup 23} m{sup −2}. XPS analysis evidenced the formation of W{sub x}N{sub y} layers with nitrogen concentration in the range of 1–10% depending on the initial morphology and structure of the W samples. In all analyzed cases, nitrogen was bound and retained within the first 6 nm below the surface and no further diffusion of N into the bulk was observed.

  3. Development of a magnetized coaxial plasma gun for compact toroid injection into the C-2 field-reversed configuration device.

    Science.gov (United States)

    Matsumoto, T; Sekiguchi, J; Asai, T; Gota, H; Garate, E; Allfrey, I; Valentine, T; Morehouse, M; Roche, T; Kinley, J; Aefsky, S; Cordero, M; Waggoner, W; Binderbauer, M; Tajima, T

    2016-05-01

    A compact toroid (CT) injector was developed for the C-2 device, primarily for refueling of field-reversed configurations. The CTs are formed by a magnetized coaxial plasma gun (MCPG), which consists of coaxial cylindrical electrodes and a bias coil for creating a magnetic field. First, a plasma ring is generated by a discharge between the electrodes and is accelerated by Lorenz self-force. Then, the plasma ring is captured by an interlinkage flux (poloidal flux). Finally, the fully formed CT is ejected from the MCPG. The MCPG described herein has two gas injection ports that are arranged tangentially on the outer electrode. A tungsten-coated inner electrode has a head which can be replaced with a longer one to extend the length of the acceleration region for the CT. The developed MCPG has achieved supersonic CT velocities of ∼100 km/s. Plasma parameters for electron density, electron temperature, and the number of particles are ∼5 × 10(21) m(-3), ∼40 eV, and 0.5-1.0 × 10(19), respectively.

  4. Development of a magnetized coaxial plasma gun for compact toroid injection into the C-2 field-reversed configuration device

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, T., E-mail: cstd14003@g.nihon-u.ac.jp; Sekiguchi, J.; Asai, T. [College of Science and Technology, Nihon University, 1-8-14 Kanda, Chiyoda-ku, Tokyo 1018308 (Japan); Gota, H.; Garate, E.; Allfrey, I.; Valentine, T.; Morehouse, M.; Roche, T.; Kinley, J.; Aefsky, S.; Cordero, M.; Waggoner, W.; Binderbauer, M. [Tri Alpha Energy, Inc., P.O. Box 7010 Rancho Santa Margarita, California 92688 (United States); Tajima, T. [Tri Alpha Energy, Inc., P.O. Box 7010 Rancho Santa Margarita, California 92688 (United States); Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States)

    2016-05-15

    A compact toroid (CT) injector was developed for the C-2 device, primarily for refueling of field-reversed configurations. The CTs are formed by a magnetized coaxial plasma gun (MCPG), which consists of coaxial cylindrical electrodes and a bias coil for creating a magnetic field. First, a plasma ring is generated by a discharge between the electrodes and is accelerated by Lorenz self-force. Then, the plasma ring is captured by an interlinkage flux (poloidal flux). Finally, the fully formed CT is ejected from the MCPG. The MCPG described herein has two gas injection ports that are arranged tangentially on the outer electrode. A tungsten-coated inner electrode has a head which can be replaced with a longer one to extend the length of the acceleration region for the CT. The developed MCPG has achieved supersonic CT velocities of ∼100 km/s. Plasma parameters for electron density, electron temperature, and the number of particles are ∼5 × 10{sup 21} m{sup −3}, ∼40 eV, and 0.5–1.0 × 10{sup 19}, respectively.

  5. Aqueous reactive species induced by a PCB surface micro-discharge air plasma device: a quantitative study

    Science.gov (United States)

    Chen, Chen; Li, Fanying; Chen, Hai-Lan; Kong, Michael G.

    2017-11-01

    This paper presents a quantitative investigation on aqueous reactive species induced by air plasma generated from a printed circuit board surface micro-discharge (SMD) device. Under the conditions amenable for proliferation of mammalian cells, concentrations of ten types of reactive oxygen and nitrogen species (RONS) in phosphate buffering solution (PBS) are measured by chemical fluorescent assays and electron spin resonance spectroscopy (ESR). Results show that concentrations of several detected RNS (NO2- , NO3- , peroxynitrites, and NO2\\centerdot ) are higher than those of ROS (H2O2, O2\\centerdot - , and 1O2) in the air plasma treated solution. Concentrations of NO3- can reach 150 times of H2O2 with 60 s plasma treatment. For short-lived species, the air plasma generates more copious peroxynitrite than other RONS including NO2\\centerdot , O2\\centerdot - , 1O2, and N{{O}\\centerdot } in PBS. In addition, the existence of reaction between H2O2 and NO2- /HNO2 to produce peroxynitrite is verified by the chemical scavenger experiments. The reaction relations between detected RONS are also discussed.

  6. Toward High-Performance Coatings for Biomedical Devices: Study on Plasma-Deposited Fluorocarbon Films and Ageing in PBS

    Directory of Open Access Journals (Sweden)

    Diego Mantovani

    2010-03-01

    Full Text Available High performance coatings tailored to medical devices represent a recognised approach to modulate surface properties. Plasma-deposited fluorocarbon films have been proposed as a potential stent coating. Previous studies have shown promising adhesion properties: the 35 nm-thick film sustained plastic deformation up to 25% such as induced during the clinical implantation. In this study, the compositional and morphological changes of plasma-deposited fluorocarbon films were examined during ageing in a pseudo-physiological medium, a phosphate buffer solution (PBS, by angle-resolved XPS, FT-IR data and AFM images. The evolution of the ageing process is discussed: defluorination and crosslinking yielded an oxidized protective top layer onto the films, which showed further degradation.

  7. Direct measurement of refracted trajectory of transmitting electron cyclotron beam through plasma on the Large Helical Device

    Directory of Open Access Journals (Sweden)

    Takahashi Hiromi

    2015-01-01

    Full Text Available The electron-cyclotron (EC -beam refraction due to the presence of plasma was investigated in the Large Helical Device. The transmitted-EC-beam measurement system was constructed and the beam pattern on the opposite side of the irradiated surface was measured using an IR camera. Clear dependence of the EC-beam refraction on the electron density was observed and the beam shift in the toroidal direction showed good agreement with the ray-trace calculation of TRAVIS. The influence of the peripheral density profile and the thermal effect on the beam refraction were discussed.

  8. Two hump-shaped angular distributions of neutrons and soft X-rays in a small plasma focus device.

    Science.gov (United States)

    Habibi, Morteza

    2017-12-28

    Angular distributions of soft X-rays (SXRs) and neutrons emitted by a small plasma focus device (PFD) were investigated simultaneously using TLD-100 dosimeters and Geiger-Muller activation counters, respectively. The distributions represented two humps with a small dip at the angular position 0° and reduced from the angles of ± 15° and ± 30° for the neutrons and SXRs, respectively. The maximum yield of 2.98 × 108 neutrons per shot of the device was obtained at 13.5kV and 6.5mbar. A time of flight (TOF) of 75.2ns between the hard X-ray and the neutron peaks corresponds to neutrons with energy of 2.67MeV. A similar behavior was observed between the angular distributions of neutron and soft X-ray emissions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. 6.4 GHz ECR ion source at VECC

    Indian Academy of Sciences (India)

    Iq ∝ neV. So, the presence of higher density of energetic electrons in the plasma is essential for good amount of high charge state extraction. The higher microwave power (P) under suitable resonance condition creates increased number of energetic ionizing electrons (ne). P ∝ VneTe/τe where Te,V and τe are electron ...

  10. The long way to steady state fusion plasmas - the superconducting stellarator device Wendelstein 7-X

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    The stable generation of high temperature Hydrogen plasmas (ion and electron temperature in the range 10-20 keV) is the basis for the use of nuclear fusion to generate heat and thereby electric power. The most promising path is to use strong, toroidal, twisted magnetic fields to confine the electrically charged plasma particles in order to avoid heat losses to the cold, solid wall elements. Two magnetic confinement concepts have been proven to be most suitable: (a) the tokamak and (b) the stellarator. The stellarator creates the magnetic field by external coils only, the tokamak by combining the externally created field with the magnetic field generated by a strong current in the plasma. “Wendelstein 7-X” is the name of a large superconducting stellarator that went successfully into operation after 15 years of construction. With 30 m3 plasma volume, 3 T magnetic field on axis, and 10 MW micro wave heating power, Hydrogen plasmas are generated that allow one to establish a scientific basis for the extrapol...

  11. Aquaregia and Oxygen Plasma Treatments on Fluorinated Tin Oxide for Assembly of PLEDs Devices Using OC1C10-PPV as Emissive Polymer

    Directory of Open Access Journals (Sweden)

    Emerson Roberto SANTOS

    2009-02-01

    Full Text Available In this work were carried out treatments with oxygen plasma and aquaregia on fluorinated tin oxide (FTO films varying the treatment times. After treatments, the samples were analyzed by techniques measurements: sheet resistance, thickness, Hall effect, transmittance and superficial roughness. Devices using FTO/PEDOT:PSS/OC1C10-PPV/Al were assembled. In this experiment some variations were observed by sheet resistance and thickness and Hall effect measurements indicated most elevated carriers concentration and resistivity for aquaregia than that oxygen plasma. The roughness was elevated for the first minutes with treatment by aquaregia too. In the I-V curves the aquaregia devices presented the lowest threshold voltage for 30 minutes and devices treated by oxygen plasma presented a behavior most resistivity different of typical curves for PLEDs devices.

  12. Thrust Stand Measurements Using Alternative Propellants in the Microwave Assisted Discharge Inductive Plasma Accelerator

    Science.gov (United States)

    Hallock, Ashley K.; Polzin, Kurt A.

    2011-01-01

    Storable propellants (for example water, ammonia, and hydrazine) are attractive for deep space propulsion due to their naturally high density at ambient interplanetary conditions, which obviates the need for a cryogenic/venting system. Water in particular is attractive due to its ease of handling and availability both terrestrially and extra-terrestrially. While many storable propellants are reactive and corrosive, a propulsion scheme where the propellant is insulated from vulnerable (e.g. metallic) sections of the assembly would be well-suited to process these otherwise incompatible propellants. Pulsed inductive plasma thrusters meet this criterion because they can be operated without direct propellant-electrode interaction. During operation of these devices, electrical energy is capacitively stored and then discharged through an inductive coil creating a time-varying current in the coil that interacts with a plasma covering the face of the coil to induce a plasma current. Propellant is accelerated and expelled at a high exhaust velocity (O(10-100 km/s)) by the Lorentz body force arising from the interaction of the magnetic field and the induced plasma current. While this class of thruster mitigates the life-limiting issues associated with electrode erosion, many pulsed inductive plasma thrusters require high pulse energies to inductively ionize propellant. The Microwave Assisted Discharge Inductive Plasma Accelerator (MAD-IPA) is a pulsed inductive plasma thruster that addressees this issue by partially ionizing propellant inside a conical inductive coil before the main current pulse via an electron cyclotron resonance (ECR) discharge. The ECR plasma is produced using microwaves and a static magnetic field from a set of permanent magnets arranged to create a thin resonance region along the inner surface of the coil, restricting plasma formation, and in turn current sheet formation, to a region where the magnetic coupling between the plasma and the theta

  13. Design of a 100 J Dense Plasma Focus Z-pinch Device as a Portable Neutron Source

    Science.gov (United States)

    Jiang, Sheng; Higginson, Drew; Link, Anthony; Liu, Jason; Schmidt, Andrea

    2015-11-01

    The dense plasma focus (DPF) Z-pinch devices are capable of accelerating ions to high energies through MV/mm-scale electric fields. When deuterium is used as the filling gas, neutrons are generated through beam-target fusion when fast D beams collide with the bulk plasma. The neutron yield on a DPF scales favorably with current, and could be used as portable sources for active interrogation. Past DPF experiments have been optimized empirically. Here we use the particle-in-cell (PIC) code LSP to optimize a portable DPF for high neutron yield prior to building it. In this work, we are designing a DPF device with about 100 J of energy which can generate 106 - 107 neutrons. The simulations are run in the fluid mode for the rundown phase and are switched to kinetic to capture the anomalous resistivity and beam acceleration process during the pinch. A scan of driver parameters, anode geometries and gas pressures are studied to maximize the neutron yield. The optimized design is currently under construction. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 and supported by the Laboratory Directed Research and Development Program (15-ERD-034) at LLNL.

  14. Fast blood plasma separation device for point-of-care applications

    Czech Academy of Sciences Publication Activity Database

    Ďurč, P.; Foret, František; Kubáň, Petr

    2018-01-01

    Roč. 183, JUN (2018), s. 55-60 ISSN 0039-9140 Institutional support: RVO:68081715 Keywords : blood plasma separation * capillary electrophoresis * point of care analysis * methanol * metabolites Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 4.162, year: 2016

  15. Magnetic Effects in a Moderate-Temperature, High-Beta, Toroidal Plasma Device

    Science.gov (United States)

    Edwards, W. F.; Singh, A. K.; Held, E. D.

    2011-10-01

    A small toroidal machine (STOR-1M; minor radius 4.5 cm), on loan from the University of Saskatchewan, has been modified to operate at hydrogen ionization levels ~0.1%, beta values between 0.1 and 1, electron number density ~5x1016/m3, temperature ~5 eV, and applied toroidal magnetic field ~20 gauss. Plasma is generated using magnetron-produced microwaves. Langmuir and Hall probes determine radial profiles of electron number density, temperature, and magnetic field. For most values of the externally-applied magnetic field, the internal field is the same with or without plasma, however, in a narrow window of B, diamagnetism and other effects are present. The effect is observed with no externally induced current; plasma currents are self generated through some sort of relaxation process. Beta and radius conditions correlate well with similar magnetic structures in the laboratory (eg., plasma focus, Z pinch) and in space (eg., Venus flux ropes, solar coronal loops).

  16. Complex plasma experimental device – A test bed for studying dust ...

    Indian Academy of Sciences (India)

    2016-11-03

    Nov 3, 2016 ... advanced image analysis techniques are presented in this paper. Keywords. Dusty plasma; vortices; particle ... used for analysing the experimental data obtained using the specialized sCMOS camera are ..... low pressures, the dust particle oscillations gain big- ger amplitudes due to the dominance of ion ...

  17. Dry etching of ITO by magnetic pole enhanced inductively coupled plasma for display and biosensing devices

    Energy Technology Data Exchange (ETDEWEB)

    Meziani, T. [European Commission, Joint Research Centre, Institute for Health and Consumer Protection, 21020 Ispra (Vatican City State, Holy See,) (Italy)]. E-mail: tarik.meziani@jrc.it; Colpo, P. [European Commission, Joint Research Centre, Institute for Health and Consumer Protection, 21020 Ispra (Va) (Italy)]. E-mail: pascal.colpo@jrc.it; Lambertini, V. [Centro Ricerche Fiat, Strada Torino 50, 10043 Orbassano (TO) (Italy); Ceccone, G. [European Commission, Joint Research Centre, Institute for Health and Consumer Protection, 21020 Ispra (Va) (Italy); Rossi, F. [European Commission, Joint Research Centre, Institute for Health and Consumer Protection, 21020 Ispra (Va) (Italy)

    2006-03-15

    The dry etching of indium tin oxide (ITO) layers deposited on glass substrates was investigated in a high density inductively coupled plasma (ICP) source. This innovative low pressure plasma source uses a magnetic core in order to concentrate the electromagnetic energy on the plasma and thus provides for higher plasma density and better uniformity. Different gas mixtures were tested containing mainly hydrogen, argon and methane. In Ar/H{sub 2} mixtures and at constant bias voltage (-100 V), the etch rate shows a linear dependence with input power varying the same way as the ion density, which confirms the hypothesis that the etching process is mainly physical. In CH{sub 4}/H{sub 2} mixtures, the etch rate goes through a maximum for 10% CH{sub 4} indicating a participation of the radicals to the etching process. However, the etch rate remains quite low with this type of gas mixture (around 10 nm/min) because the etching mechanism appears to be competing with a deposition process. With CH{sub 4}/Ar mixtures, a similar feature appeared but the etch rate was much higher, reaching 130 nm/min at 10% of CH{sub 4} in Ar. The increase in etch rate with the addition of a small quantity of methane indicates that the physical etching process is enhanced by a chemical mechanism. The etching process was monitored by optical emission spectroscopy that appeared to be a valuable tool for endpoint detection.

  18. A sociedade dos ecrãs : entre ver e ser visto

    OpenAIRE

    Almeida, Hugo Picado de

    2012-01-01

    Os ecrãs estão hoje por toda a parte. No nosso dia-a-dia encontramo-nos cada vez mais diante deles, e as previsões parecem apontar para a intensificação da tendência. Se a nossa vida está hoje eminentemente dentro do ecrã, por ele recebendo informação e acedendo ao outro e ao mundo, através dele construindo narrativas e a própria mundividência, devemos considerar que essa relação, tendencialmente permanente e ubíqua, influirá sobre as configurações da sociedade, modelando compo...

  19. The new ECR charge breeder for the Selective Production of Exotic Species project at INFN—Laboratori Nazionali di Legnaro

    Energy Technology Data Exchange (ETDEWEB)

    Galatà, A., E-mail: alessio.galata@lnl.infn.it; Patti, G.; Roncolato, C. [INFN-Laboratori Nazionali di Legnaro, Viale dell’Università 2, 35020 Padova, Legnaro (Italy); Angot, J.; Lamy, T. [LPSC-Université Grenoble Alpes-CNRS/IN2P3, 53 rue des Martyrs, 38026 Grenoble CEDEX (France)

    2016-02-15

    The Selective Production of Exotic Species (SPES) project is an ISOL facility under construction at Istituto Nazionale di Fisica Nucleare–Laboratori Nationali di Legnaro (INFN-LNL). 1+ radioactive ions, produced and extracted from the target-ion-source system, will be charge bred to high charge states by an ECR charge breeder (SPES-CB): the project will adopt an upgraded version of the PHOENIX charge breeder, developed since about twenty years by the Laboratoire de Physique Subatomique et de Cosmologie (LPSC). The collaboration between LNL and LPSC started in 2010 with charge breeding experiments performed on the LPSC test bench and led, in June 2014, to the signature of a Research Collaboration Agreement for the delivery of a complete charge breeder and ancillaries, satisfying the SPES requirements. Important technological aspects were tackled during the construction phase, as, for example, beam purity issues, electrodes alignment, and vacuum sealing. This phase was completed in spring 2015, after which the qualification tests were carried out at LPSC on the 1+/q+ test stand. This paper describes the characteristics of the SPES-CB, with particular emphasis on the results obtained during the qualification tests: charge breeding of Ar, Xe, Rb, and Cs satisfied the SPES requirements for different intensities of the injected 1+ beam, showing very good performances, some of which are “best ever” for this device.

  20. The new ECR charge breeder for the Selective Production of Exotic Species project at INFN—Laboratori Nazionali di Legnaro

    Science.gov (United States)

    Galatà, A.; Patti, G.; Roncolato, C.; Angot, J.; Lamy, T.

    2016-02-01

    The Selective Production of Exotic Species (SPES) project is an ISOL facility under construction at Istituto Nazionale di Fisica Nucleare-Laboratori Nationali di Legnaro (INFN-LNL). 1+ radioactive ions, produced and extracted from the target-ion-source system, will be charge bred to high charge states by an ECR charge breeder (SPES-CB): the project will adopt an upgraded version of the PHOENIX charge breeder, developed since about twenty years by the Laboratoire de Physique Subatomique et de Cosmologie (LPSC). The collaboration between LNL and LPSC started in 2010 with charge breeding experiments performed on the LPSC test bench and led, in June 2014, to the signature of a Research Collaboration Agreement for the delivery of a complete charge breeder and ancillaries, satisfying the SPES requirements. Important technological aspects were tackled during the construction phase, as, for example, beam purity issues, electrodes alignment, and vacuum sealing. This phase was completed in spring 2015, after which the qualification tests were carried out at LPSC on the 1+/q+ test stand. This paper describes the characteristics of the SPES-CB, with particular emphasis on the results obtained during the qualification tests: charge breeding of Ar, Xe, Rb, and Cs satisfied the SPES requirements for different intensities of the injected 1+ beam, showing very good performances, some of which are "best ever" for this device.

  1. Proceedings of 1999 U.S./Japan Workshop (99FT-05) On High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices

    Energy Technology Data Exchange (ETDEWEB)

    NYGREN,RICHARD E.; STAVROS,DIANA T.

    2000-06-01

    The 1999 US-Japan Workshop on High Heat Flux Components and Plasma Surface Interactions in Next Step Fusion Devices was held at the St. Francis Hotel in Santa Fe, New Mexico, on November 1-4, 1999. There were 42 presentations as well as discussion on technical issues and planning for future collaborations. The participants included 22 researchers from Japan and the United States as well as seven researchers from Europe and Russia. There have been important changes in the programs in both the US and Japan in the areas of plasma surface interactions and plasma facing components. The US has moved away from a strong focus on the ITER Project and has introduced new programs on use of liquid surfaces for plasma facing components, and operation of NSTX has begun. In Japan, the Large Helical Device began operation. This is the first large world-class confinement device operating in a magnetic configuration different than a tokamak. In selecting the presentations for this workshop, the organizers sought a balance between research in laboratory facilities or confinement devices related to plasma surface interactions and experimental research in the development of plasma facing components. In discussions about the workshop itself, the participants affirmed their preference for a setting where ''work-in-progress'' could be informally presented and discussed.

  2. MIP Plasma Decapsulation of Copper-wired Semiconductor Devices for Failure Analysis

    NARCIS (Netherlands)

    Tang, J.

    2014-01-01

    The majority of Integrated Circuit (IC) devices are encapsulated in wire-bonded plastic IC packages. Epoxy molding compound is used as the encapsulation material and gold was used as the bonding wire material. However, the increase of gold material price from 400 USD/ounce in year 2005 to 1400

  3. Study of ICRF wave propagation and plasma coupling efficiency in a linear magnetic mirror device

    Energy Technology Data Exchange (ETDEWEB)

    Peng, S.Y.

    1991-07-01

    Ion Cyclotron Range of Frequency (ICRF) wave propagation in an inhomogeneous axial magnetic field in a cylindrical plasma-vacuum system has historically been inadequately modelled. Previous works either sacrifice the cylindrical geometry in favor of a simpler slab geometry, concentrate on the resonance region, use a single mode to represent the entire field structure, or examine only radial propagation. This thesis performs both analytical and computational studies to model the ICRF wave-plasma coupling and propagation problem. Experimental analysis is also conducted to compare experimental results with theoretical predictions. Both theoretical as well as experimental analysis are undertaken as part of the thesis. The theoretical studies simulate the propagation of ICRF waves in an axially inhomogeneous magnetic field and in cylindrical geometry. Two theoretical analysis are undertaken - an analytical study and a computational study. The analytical study treats the inhomogeneous magnetic field by transforming the (r,z) coordinate into another coordinate system ({rho},{xi}) that allows the solution of the fields with much simpler boundaries. The plasma fields are then Fourier transformed into two coupled convolution-integral equations which are then differenced and solved for both the perpendicular mode number {alpha} as well as the complete EM fields. The computational study involves a multiple eigenmode computational analysis of the fields that exist within the plasma-vacuum system. The inhomogeneous axial field is treated by dividing the geometry into a series of transverse axial slices and using a constant dielectric tensor in each individual slice. The slices are then connected by longitudinal boundary conditions.

  4. Comparison of measured and computed radial trajectories of plasma focus devices UMDPF1 and UMDPF0

    Energy Technology Data Exchange (ETDEWEB)

    Lim, L. H.; Yap, S. L., E-mail: yapsl@um.edu.my; Lim, L. K.; Lee, M. C.; Poh, H. S.; Ma, J. [Plasma Technology Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Yap, S. S. [UMPEDAC, University of Malaya, 50603 Kuala Lumpur (Malaysia); Faculty of Engineering, Multimedia University, Cyberjaya, 63100 Selangor (Malaysia); Lee, S. [Plasma Technology Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); INTI International University, 71800 Nilai (Malaysia); Institute for Plasma Focus Studies, 32 Oakpark Drive, Chadstone 3148 (Australia)

    2015-09-15

    In published literature, there has been scant data on radial trajectory of the plasma focus and no comparison of computed with measured radial trajectory. This paper provides the first such comparative study. We compute the trajectories of the inward-moving radial shock and magnetic piston of UMDPF1 plasma focus and compare these with measured data taken from a streak photograph. The comparison shows agreement with the measured radial trajectory in terms of average speeds and general shape of trajectory. This paper also presents the measured trajectory of the radially compressing piston in another machine, the UMDPF0 plasma focus, confirming that the computed radial trajectory also shows similar general agreement. Features of divergence between the computed and measured trajectories, towards the end of the radial compression, are discussed. From the measured radial trajectories, an inference is made that the neutron yield mechanism could not be thermonuclear. A second inference is made regarding the speeds of axial post-pinch shocks, which are recently considered as a useful tool for damage testing of fusion-related wall materials.

  5. First ECR-Ionized Noble Gas Radioisotopes at ISOLDE

    CERN Document Server

    Wenander, F; Gaubert, G; Jardin, P; Lettry, Jacques

    2004-01-01

    The production of light noble gas radioisotopes with high ionization potentials has been hampered by modest ionization efficiencies for standard plasma ion-sources. However, the decay losses are minimal as the lingering time of light noble gases within plasma ion-sources is negligible when compared to its diffusion out of the target material. Previous singly charged ECRIS have shown a higher efficiency but also a lingering time of the order of 1 s and a total weight that prevents remote handling by the ISOLDE robot. The compact MINIMONO efficiently addressed the lingering time and weight issues. In addition, the MINIMONO maintained the high off-line ionization efficiency for light noble gases. This paper describes a standard ISOLDE target unit equipped with a MINIMONO ion-source and the first tests. The ion-source has been tested off-line and equipped with a CaO target for on-line tests. Valuable information was gained about high current (100-500 muA) transport through the ISOLDE mass separators designed for ...

  6. Stimulated Parametric Decay of Large Amplitude Alfvén waves in the Large Plasma Device (LaPD)

    Science.gov (United States)

    Dorfman, S. E.; Carter, T.; Pribyl, P.; Tripathi, S.; Van Compernolle, B.; Vincena, S. T.

    2012-12-01

    Alfvén waves, a fundamental mode of magnetized plasmas, are ubiquitous in lab and space. While the linear behaviour of these waves has been extensively studied [1], non-linear effects are important in many real systems, including the solar wind and solar corona. In particular, a parametric decay process in which a large amplitude Alfvén wave decays into an ion acoustic wave and backward propagating Alfvén wave may be key to the spectrum of solar wind turbulence. Ion acoustic waves have been observed in the heliosphere, but their origin and role have not yet been determined [2]. Such waves produced by parametric decay in the corona could contribute to coronal heating [3]. Parametric decay has also been suggested as an intermediate instability mediating the observed turbulent cascade of Alfvén waves to small spatial scales [4]. The present laboratory experiments aim to stimulate the parametric decay process by launching counter-propagating Alfvén waves from antennas placed at either end of the Large Plasma Device (LaPD). The resulting beat response has a dispersion relation consistent with an ion acoustic wave. Also consistent with a stimulated decay process: 1) The beat amplitude peaks when the frequency difference between the two Alfvén waves is near the value predicted by Alfvén-ion acoustic wave coupling. 2) This peak beat frequency scales with antenna and plasma parameters as predicted by three wave matching. 3) The beat amplitude peaks at the same location as the magnetic field from the Alfvén waves. 4) The beat wave is carried by the ions and propagates in the direction of the higher-frequency Alfvén wave. Strong damping observed after the pump Alfvén waves are turned off and observed heating of the plasma by the Alfvén waves are under investigation. [1] W. Gekelman, J. Geophys. Res., 104:14417-14436, July 1999. [2] A. Mangeney,et. al., Annales Geophysicae, Volume 17, Number 3 (1999). [3] F. Pruneti, F and M. Velli, ESA Spec. Pub. 404, 623 (1997

  7. Fullerene-rare gas mixed plasmas in an electron cyclotron resonance ion source

    Energy Technology Data Exchange (ETDEWEB)

    Asaji, T., E-mail: asaji@oshima-k.ac.jp; Ohba, T. [Oshima National College of Maritime Technology, 1091-1 Komatsu, Suo-oshima, Oshima, Yamaguchi 742-2193 (Japan); Uchida, T.; Yoshida, Y. [Bio-Nano Electronics Research Centre, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585 (Japan); Minezaki, H.; Ishihara, S. [Graduate School of Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585 (Japan); Racz, R.; Biri, S. [Institute of Nuclear Research (ATOMKI), H-4026 Debrecen, Bem Tér 18/c (Hungary); Muramatsu, M.; Kitagawa, A. [National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Kato, Y. [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan)

    2014-02-15

    A synthesis technology of endohedral fullerenes such as Fe@C{sub 60} has developed with an electron cyclotron resonance (ECR) ion source. The production of N@C{sub 60} was reported. However, the yield was quite low, since most fullerene molecules were broken in the ECR plasma. We have adopted gas-mixing techniques in order to cool the plasma and then reduce fullerene dissociation. Mass spectra of ion beams extracted from fullerene-He, Ar or Xe mixed plasmas were observed with a Faraday cup. From the results, the He gas mixing technique is effective against fullerene destruction.

  8. Inductively coupled plasma etching and processing techniques for type-II InAs/GaSb superlattices infrared detectors toward high fill factor focal plane arrays

    Science.gov (United States)

    Huang, E. K.; Nguyen, B.-M.; Hoffman, D.; Delaunay, P.-Y.; Razeghi, M.

    2009-01-01

    A challenge for type-II InAs/GaSb superlattice (T2SL) photodetectors is to achieve high fill factor, high aspect ratio etching for third generation focal plane arrays (FPAs). Initially, we compare the morphological and electrical results of single element T2SL photodiodes after BCl3/Ar inductively coupled plasma (ICP) and electron cyclotron resonance (ECR) dry etching. Using a Si3N4 hard mask, ICP-etched structures exemplify greater sidewall verticality and smoothness, which are essential toward the realization of high fill factor FPAs. ICP-etched single element devices with SiO2 passivation that are 9.3μm in cutoff wavelength achieved vertical sidewalls of 7.7μm in depth with a resistance area product at zero bias of greater than 1,000 Ωcm2 and maximum differential resistance in excess of 10,000 Ωcm2 at 77K. By only modifying the etching technique in the fabrication steps, the ICP-etched photodiodes showed an order of magnitude decrease in their dark current densities in comparison to the ECR-etched devices. Finally, high aspect ratio etching is demonstrated on mutli-element arrays with 3μm-wide trenches that are 11μm deep.

  9. Numerical magnetohydrodynamic analysis of Large Helical Device plasmas with magnetic axis swing

    Science.gov (United States)

    Ichiguchi, K.; Sakakibara, S.; Ohdachi, S.; Carreras, B. A.

    2013-01-01

    A partial collapse observed in magnetic axis swing experiments in the Large Helical Device (LHD) is analyzed with a nonlinear magnetohydrodynamic (MHD) simulation. Real time control of the background field in the operation is incorporated by means of a multi-scale numerical scheme in the simulation. The simulation result indicates that the changing background field accelerates the growth of an infernal-like mode and causes the partial collapse.

  10. Silencing of NbECR encoding a putative enoyl-CoA reductase results in disorganized membrane structures and epidermal cell ablation in Nicotiana benthamiana.

    Science.gov (United States)

    Park, Jong-A; Kim, Tae-Wuk; Kim, Seong-Ki; Kim, Woo Taek; Pai, Hyun-Sook

    2005-08-15

    The very long chain fatty acids (VLCFAs) are synthesized by the microsomal fatty acid elongation system in plants. We investigated cellular function of NbECR putatively encoding enoyl-CoA reductase that catalyzes the last step of VLCFA elongation in Nicotiana benthamiana. Virus-induced gene silencing of NbECR produced necrotic lesions with typical cell death symptoms in leaves. In the affected tissues, ablation of the epidermal cell layer preceded disintegration of the whole leaf cell layers, and disorganized cellular membrane structure was evident. The amount of VLCFAs was reduced in the NbECR VIGS lines, suggesting NbECR function in elongation of VLCFAs. The results demonstrate that NbECR encodes a putative enoyl-CoA reductase and that the NbECR activity is essential for membrane biogenesis in N. benthamiana.

  11. DESTRUCTION OF NEUTRAL PARTICLES IN A DEVICE FOR PRODUCING A HIGH DENSITY PLASMA

    Science.gov (United States)

    Simon, A.

    1962-05-01

    A method and apparatus are described for burning out neutral particles in an evacuated region and within a strong magnetic field. The method comprises injecting energetic molecular ions into the region perpendicular to the magnetic field and into the path of a dissociating, energetic arc discharge, the atomic ions formed in the dissociating process being trapped by the magnetic field, and then increasing the value of the trapped atomic ion current to such a value that the neutral particles are destroyed faster than they are formed, thereby causing a dense, energetic plasma to be built up and sustained by the magnetic field. (AEC)

  12. Spectral survey of helium lines in a linear plasma device for use in HELIOS imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ray, H. B., E-mail: rayhb@ornl.gov [University of Tennessee, Knoxville, Tennessee 37996 (United States); Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Biewer, T. M.; Fehling, D. T.; Isler, R. C.; Unterberg, E. A. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2016-11-15

    Fast visible cameras and a filterscope are used to examine the visible light emission from Oak Ridge National Laboratory’s Proto-MPEX. The filterscope has been configured to perform helium line ratio measurements using emission lines at 667.9, 728.1, and 706.5 nm. The measured lines should be mathematically inverted and the ratios compared to a collisional radiative model (CRM) to determine T{sub e} and n{sub e}. Increasing the number of measurement chords through the plasma improves the inversion calculation and subsequent T{sub e} and n{sub e} localization. For the filterscope, one spatial chord measurement requires three photomultiplier tubes (PMTs) connected to pellicle beam splitters. Multiple, fast visible cameras with narrowband filters are an alternate technique for performing these measurements with superior spatial resolution. Each camera contains millions of pixels; each pixel is analogous to one filterscope PMT. The data can then be inverted and the ratios compared to the CRM to determine 2-dimensional “images” of T{sub e} and n{sub e} in the plasma. An assessment is made in this paper of the candidate He I emission lines for an imaging technique.

  13. Study of the thermal effect on silicon surface induced by ion beam from plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Z., E-mail: pscientific5@aec.org.sy [Scientific Service Department, Atomic Energy Commission of Syria, P.O. Box: 6091, Damascus (Syrian Arab Republic); Ahmad, M. [IBA Laboratory, Atomic Energy Commission of Syria, P.O. Box: 6091, Damascus (Syrian Arab Republic); Chemistry Department, Atomic Energy Commission of Syria, P.O. Box: 6091, Damascus (Syrian Arab Republic); Al-Hawat, Sh.; Akel, M. [Physics Department, Atomic Energy Commission of Syria, P.O. Box: 6091, Damascus (Syrian Arab Republic)

    2017-04-01

    Structural modifications in form of ripples and cracks are induced by nitrogen ions from plasma focus on silicon surface. The investigation of such structures reveals correlation between ripples and cracks formation in peripheral region of the melt spot. The reason of such correlation and structure formation is explained as result of thermal effect. Melting and resolidification of the center of irradiated area occur within one micro second of time. This is supported by a numerical simulation used to investigate the thermal effect induced by the plasma focus ion beams on the silicon surface. This simulation provides information about the temperature profile as well as the dynamic of the thermal propagation in depth and lateral directions. In accordance with the experimental observations, that ripples are formed in latter stage after the arrival of last ion, the simulation shows that the thermal relaxation takes place in few microseconds after the end of the ion beam arrival. Additionally, the dependency of thermal propagation and relaxation on the distance of the silicon surface from the anode is presented.

  14. Potential profile near the virtual cathode in a dusty plasma device

    Science.gov (United States)

    Rathod, Dinesh; Dash, Saroj Kumar; Sarma, Arun

    2017-10-01

    Existence of a virtual cathode in presence of dusty plasma has been studied by theoretical and numerical analysis. Using basic equations of charge dust, ions and electrons, the behavior of the potential in presence of dust has been calculated and plotted as a function of dust density. It was found that there is a change in potential difference between cathode and sheath potential which changes the threshold wall temperature compared to normal plasma condition. The threshold wall temperature has been increased due to the ability of micro-particles acquiring some electron charge and hence, reducing potential at the wall. Further with different values of α(depends on dust density), threshold temperature remained same for an observed virtual cathode. Hence, behavior of potential was plotted for different αwith increasing wall temperatures. It has been observed that, at lower dust density, double layer like structure is formed near the virtual cathode. Occurrence of two virtual cathodes is observed, one before threshold temperature and one after it. However, irrespective of variation of potential difference near the wall and existence of two virtual cathodes, threshold temperature remained same. The authors would like to thank Science and Engineering Research Board(SERB) for their Grants and support.

  15. Nonlinear Excitation of Acoustic Modes by Large Amplitude Alfvén waves in the Large Plasma Device (LAPD)

    Science.gov (United States)

    Dorfman, S. E.; Carter, T. A.; Pribyl, P.; Tripathi, S.; Van Compernolle, B.; Vincena, S. T.; Sydora, R. D.

    2013-12-01

    Alfvén waves, a fundamental mode of magnetized plasmas, are ubiquitous in space plasmas. While the linear behavior of these waves has been extensively studied [1], non-linear effects are important in many real systems, including the solar corona and solar wind. In particular, a parametric decay process in which a large amplitude Alfvén wave decays into an ion acoustic wave and backward propagating Alfvén wave may play an important role in the coronal heating problem. Specifically, the decay of large-amplitude Alfvén waves propagating outward from the photosphere could lead to heating of the corona by the daughter ion acoustic modes [2]. As direct observational evidence of parametric decay is limited [3], laboratory experiments may play an important role in validating simple theoretical predictions and aiding in the interpretation of space measurements. Recent counter-propagating Alfvén wave experiments in the Large Plasma Device (LAPD) have recorded the first laboratory observation of the Alfvén-acoustic mode coupling at the heart of this parametric decay instability [4]. A resonance in the beat wave response produced by the two launched Alfvén waves is observed and is identified as a damped ion acoustic mode based on the measured dispersion relation. Other properties of the interaction including the spatial profile of the beat mode and response amplitude are also consistent with theoretical predictions for a three-wave interaction driven by a nonlinear ponderomotive force. Strong damping observed after the pump Alfvén waves are turned off is under investigation; a novel ion acoustic wave launcher is under development to launch the mode directly for damping studies. New experiments also aim to identify decay instabilities from a single large-amplitude Alfvén wave. In conjunction with these experiments, gyrokinetic simulation efforts are underway to scope out the relevant parameter space. [1] W. Gekelman, et. al., Phys. Plasmas 18, 055501 (2011). [2] F

  16. Glow plasma trigger for electron cyclotron resonance ion sources.

    Science.gov (United States)

    Vodopianov, A V; Golubev, S V; Izotov, I V; Nikolaev, A G; Oks, E M; Savkin, K P; Yushkov, G Yu

    2010-02-01

    Electron cyclotron resonance ion sources (ECRISs) are particularly useful for nuclear, atomic, and high energy physics, as unique high current generators of multicharged ion beams. Plasmas of gas discharges in an open magnetic trap heated by pulsed (100 micros and longer) high power (100 kW and higher) high-frequency (greater than 37.5 GHz) microwaves of gyrotrons is promising in the field of research in the development of electron cyclotron resonance sources for high charge state ion beams. Reaching high ion charge states requires a decrease in gas pressure in the magnetic trap, but this method leads to increases in time, in which the microwave discharge develops. The gas breakdown and microwave discharge duration becomes greater than or equal to the microwave pulse duration when the pressure is decreased. This makes reaching the critical plasma density initiate an electron cyclotron resonance (ECR) discharge during pulse of microwave gyrotron radiation with gas pressure lower than a certain threshold. In order to reduce losses of microwave power, it is necessary to shorten the time of development of the ECR discharge. For fast triggering of ECR discharge under low pressure in an ECRIS, we initially propose to fill the magnetic trap with the plasmas of auxiliary pulsed discharges in crossed ExB fields. The glow plasma trigger of ECR based on a Penning or magnetron discharge has made it possible not only to fill the trap with plasma with density of 10(12) cm(-3), required for a rapid increase in plasma density and finally for ECR discharge ignition, but also to initially heat the plasma electrons to T(e) approximately = 20 eV.

  17. Collaborative Research: Fundamental Studies of Plasma Control Using Surface Embedded Electronic Devices

    Energy Technology Data Exchange (ETDEWEB)

    Overzet, Lawrence J. [Univ. of Texas, Dallas, TX (United States); Raja, L. [Univ. of Texas, Austin, TX (United States)

    2015-06-06

    The research program was collaborative between the researchers at the University of Texas at Dallas and the University of Texas at Austin. The primary subject of this program was to investigate the possibility of active control of secondary electron emission (SEE) from surfaces in contact with plasmas and thereby actively control plasmas. Very few studies of ion-induced electron emission (IIEE) from semiconductors exist, and those that do exist primarily used high-energy ion beams in the experiments. Furthermore, those few studies took extreme measures to ensure that the measurements were performed on atomically clean surfaces because of the surface sensitivity of the IIEE process. Even a small exposure to air can change the IIEE yield significantly. In addition, much of the existing data for IIEE from semiconductors was obtained in the 1950s and ‘60s, when semiconductor materials were first being refined. As a result, nearly all of that data is for p-type Ge and Si. Before this investigation, experimental data on n-type materials was virtually non-existent. While the basic theory assumed that IIEE yields ought to be substantially independent of doping type and concentration, recent measurements of near atmospheric pressure plasmas and of breakdown suggested otherwise. These indirect measurements were made on surfaces that were not atomically clean and seemed to indicate that deep sub-surface changes to the bulk conduction band electron density could lead to substantial variations in the IIEE yield. Exactly in contradiction to the generally accepted theory. Insufficient direct data existed to settle the matter. We performed both experimental measurements and theoretical calculations of IIEE yields from both Si and Ge in order to help clarify whether or not conduction band electrons substantially change the IIEE yield. We used three wafers of each material to carry out the investigation: a heavily doped p-type, an intrinsic and a heavily doped n-type wafer. There

  18. Status report of the JYFL-ECR ion sources

    CERN Document Server

    Ärje, J; Seppälä, R; Hyvönen, H; Liukkonen, E; Heikkinen, P; Nieminen, V; Ranttila, K; Hänninen, V; Lassila, A; Pakarinen, J; Koivisto, H; Xie, Z Q

    1999-01-01

    "Ion beam cocktails" are mixtures of ions with near-identical charge-to-mass ratios. In conjunction with the JYFL-ECRIS, the K130-cyclotron acts as a mass analyzer: the switch from one ion to another within the same cocktail is simple and fast. In the case of the first ion beam cocktail, the oxygen and argon gases were mixed into the gas feed line. At the same time the magnesium and iron ion beams were produced using the MIVOC method. Magnesocene and ferrocene compounds were both mixed into the MIVOC chamber. This capability is especially useful in the study of single event effects (SEE) in space electronics. All gaseous elements from H to Xe can be produced. The non-gaseous elements produced so far are C, Mg, Al, Si, S, Ca, Ti, Cr, Fe, Co, Ni, Cu, Zn and Ge. A major technical modification since the construction (in 1990) of the JYFL-ECRIS was made in January 98: a negatively biased disc replaces now the first plasma stage. After a couple of months experience with the modified source the change was found to b...

  19. Surface modification of POSS–polyimide hybrid films by atomic oxygen using ECR plasma

    Energy Technology Data Exchange (ETDEWEB)

    Duo, Shuwang, E-mail: swduo@126.com [Jiangxi Key Laboratory of Surface Engineering, Jiangxi Science and Technology Normal University, Nanchang 330013 (China); Ke, Huan; Liu, Tingzhi; Song, Mimi [Jiangxi Key Laboratory of Surface Engineering, Jiangxi Science and Technology Normal University, Nanchang 330013 (China); Li, Meishuan [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China)

    2013-07-15

    A novel polyimide (PI) hybrid nanocomposite containing polyhedral oligomeric silsesquioxane (POSS) had been prepared by copolymerization of trisilanolphenyl-POSS, 4,4′-oxydianiline (ODA), and pyromellitic dianhydride (PMDA). The atomic oxygen (AO) resistance of these PI/POSS hybrid films was tested in the ground-based AO simulation facility. Exposed and unexposed surfaces were characterized by SEM and XPS. The SEM images showed that the surface of the 20 wt.% PI/POSS became much less rough than that of the pristine PI. Mass measurements of the samples showed that the erosion yield of the PI/POSS (20 wt.%) hybrid film was 1.2 × 10{sup −25} cm{sup 3}/atom, and reduced to 4.3% of that of the PI film. The XPS data indicated that the carbon content of the near-surface region was decreased from 66.0 to 7.0 at.% after AO exposure. The ratio of oxygen and silicon concentrations in the near-surface region increased to 2.08 after AO exposure. The nanometer-sized structure of POSS, with its large surface area, had led AO-irradiated samples to form a SiO{sub 2} passivation layer, which protected the underlying polymer from further AO attack. The incorporation of POSS into the PI could dramatically improve the AO resistance of PI films in low earth orbit environment.

  20. Progress of divertor simulation research toward the realization of detached plasma using a large tandem mirror device

    Energy Technology Data Exchange (ETDEWEB)

    Nakashima, Y., E-mail: nakashma@prc.tsukuba.ac.jp [Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Takeda, H.; Ichimura, K.; Hosoi, K.; Oki, K.; Sakamoto, M.; Hirata, M.; Ichimura, M.; Ikezoe, R.; Imai, T.; Iwamoto, M.; Hosoda, Y.; Katanuma, I.; Kariya, T.; Kigure, S.; Kohagura, J.; Minami, R.; Numakura, T.; Takahashi, S.; Yoshikawa, M. [Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); and others

    2015-08-15

    This paper describes the results of the experiments performed on Tandem Mirror device GAMMA 10/PDX mainly using a new “divertor simulation experimental module (D-module)” installed on one of the end mirror exits which is specially designed to investigate the physics of plasma detachment. The additional ICRF heating in the anchor-cells, connected to both ends of the central-cell, significantly increases the density in the both cells, which attained the generation of the highest particle flux up to 10{sup 23} particles/s m{sup 2} at the end-mirror exit. H{sub 2} and noble gas injection to enhance the radiation cooling in D-module was performed and a remarkable reduction of the electron temperature (from few tens eV to <3 eV) on the target plate were successfully achieved associated with the strong reduction of particle and heat flux. A significant effect of simultaneous injection with hydrogen and noble gases for detached plasma formation was recognized for the first time.

  1. Microwave Plasma Source for Fabrication of Micro- and Nano-Crystalline Diamond Thin Films for Electronic Devices

    Science.gov (United States)

    Paosawatyanyong, Boonchoat; Rujisamphan, Nopporn; Bhanthumnavin, Worawan

    2013-01-01

    The design and utilization of an affordable compact-size high-density plasma reactor for micro- and nano-crystalline diamond (MCD/NCD) thin film deposition is presented. The system is based on a 2.45 GHz domestic microwave oven magnetron. A switching power supply module, which yields a low-voltage high-current AC filament feeding and a high-voltage low-current DC cathode bias, is constructed to serve as the magnetron power source. With a high stability of the power module combined with the usage of water cooling gaskets, over 100 h of plasma processing time was achieved without overheating or causing any damage to the magnetron. Depositions of well-faceted MCD/NCD thin films, with distinct diamond Raman characteristics, were obtained using H2-CH4 discharge with 1-5% CH4. Metal-semiconductor diode structures were fabricated using gold and aluminum as ohmic and rectifying contacts, respectively, and their responses to DC signals revealed a high rectification ratio of up to 106 in the intrinsic MCD/NCD devices.

  2. Effect of Inductive Coil Geometry on the Thrust Efficiency of a Microwave Assisted Discharge Inductive Plasma Accelerator

    Science.gov (United States)

    Hallock, Ashley; Polzin, Kurt; Emsellem, Gregory

    2012-01-01

    Pulsed inductive plasma thrusters [1-3] are spacecraft propulsion devices in which electrical energy is capacitively stored and then discharged through an inductive coil. The thruster is electrodeless, with a time-varying current in the coil interacting with a plasma covering the face of the coil to induce a plasma current. Propellant is accelerated and expelled at a high exhaust velocity (O(10-100 km/s)) by the Lorentz body force arising from the interaction of the magnetic field and the induced plasma current. While this class of thruster mitigates the life-limiting issues associated with electrode erosion, pulsed inductive plasma thrusters require high pulse energies to inductively ionize propellant. The Microwave Assisted Discharge Inductive Plasma Accelerator (MAD-IPA) [4, 5] is a pulsed inductive plasma thruster that addressees this issue by partially ionizing propellant inside a conical inductive coil via an electron cyclotron resonance (ECR) discharge. The ECR plasma is produced using microwaves and permanent magnets that are arranged to create a thin resonance region along the inner surface of the coil, restricting plasma formation, and in turn current sheet formation, to a region where the magnetic coupling between the plasma and the inductive coil is high. The use of a conical theta-pinch coil is under investigation. The conical geometry serves to provide neutral propellant containment and plasma plume focusing that is improved relative to the more common planar geometry of the Pulsed Inductive Thruster (PIT) [2, 3], however a conical coil imparts a direct radial acceleration of the current sheet that serves to rapidly decouple the propellant from the coil, limiting the direct axial electromagnetic acceleration in favor of an indirect acceleration mechanism that requires significant heating of the propellant within the volume bounded by the current sheet. In this paper, we describe thrust stand measurements performed to characterize the performance

  3. Simulation of impurity transport in the peripheral plasma due to the emission of dust in long pulse discharges on the Large Helical Device

    Directory of Open Access Journals (Sweden)

    M. Shoji

    2017-08-01

    Full Text Available Two different plasma termination processes by dust emission were observed in long pulse discharges in the Large Helical Device. One is a plasma termination caused by large amounts of carbon dust released from a lower divertor region. The other is termination caused by stainless steel (iron dust emission from the surface of a helical coil can. The effect of the dust emission on the sustainment of the long pulse discharges are investigated using a three-dimensional edge plasma transport code (EMC3-EIRENE coupled with a dust transport code (DUSTT. The simulation shows that the plasma is more influenced by the iron dust emission from the helical coil can than by the carbon dust emission from the divertor region. The simulation revealed that the plasma flow in divertor legs is quite effective for preventing dust from terminating the long pulse discharges.

  4. US-Japan workshop Q-181 on high heat flux components and plasma-surface interactions for next devices: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    McGrath, R.T. [ed.] [Sandia National Labs., Albuquerque, NM (United States); Yamashina, T. [ed.] [Hokkadio Univ. (Japan)

    1994-04-01

    This report contain viewgraphs of papers from the following sessions: plasma facing components issues for future machines; recent PMI results from several tokamaks; high heat flux technology; plasma facing components design and applications; plasma facing component materials and irradiation damage; boundary layer plasma; plasma disruptions; conditioning and tritium; and erosion/redeposition.

  5. High electronegativity multi-dipolar electron cyclotron resonance plasma source for etching by negative ions

    DEFF Research Database (Denmark)

    Stamate, Eugen; Draghici, M.

    2012-01-01

    A large area plasma source based on 12 multi-dipolar ECR plasma cells arranged in a 3 x 4 matrix configuration was built and optimized for silicon etching by negative ions. The density ratio of negative ions to electrons has exceeded 300 in Ar/SF6 gas mixture when a magnetic filter was used to re...

  6. Performance of cryocoolers in a High Temperature Superconducting ECR ion source (HTS-ECR) and its application for the High Current Injector Programme at IUAC, New Delhi

    Science.gov (United States)

    Rodrigues, G.; Mathur, Y.; Rao, U. K.; Lakshmy, P. S.; Mandal, A.; Roy, A.; Kanjilal, D.

    2017-02-01

    At the Inter University Accelerator Centre, a high current injector programme (HCI) is being developed as an alternate injector to the superconducting linear accelerator (SC-LINAC). For this purpose, a high temperature superconducting ECR ion source, PKDELIS, based on Gifford McMahon cryocoolers was designed, installed and commissioned in the Low Energy Beam Transport section of the high current injector. The ion source will inject multiply charged ions having A/q ∼ 6 for further acceleration into the downstream RFQ and DTL accelerators before final injection into the superconducting linear accelerator. The details of the design, and experimental results of the ion source together with performance of the cryocoolers are presented in this paper.

  7. Electron cyclotron resonance breakdown studies in a linear plasma ...

    Indian Academy of Sciences (India)

    Abstract. Electron cyclotron resonance (ECR) plasma breakdown is studied in a small linear cylindrical system with four different gases – hydrogen, helium, argon and nitrogen. Microwave power in the experimental system is delivered by a magnetron at 2.45 ± 0.02. GHz in TE10 mode and launched radially to have ...

  8. A study on the design of hexapole in an 18-GHz ECR ion source for heavy ion accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhan; Wei, Shaoqing; Lee, Sang Jin [Uiduk University, Gyeongju (Korea, Republic of); Choi, Suk Jin [Rare Isotope Science Project, Institute for Basic Science, Daejeon (Korea, Republic of)

    2016-06-15

    High charge state electron cyclotron resonance (ECR) ion source is important on the performance of heavy ion accelerators. In this paper, a low temperature superconductor (LTS) was used to make a hexapole coil for an 18-GHz ECR ion source. Several hexapole structures, including racetrack, graded racetrack, and saddle were implemented and analyzed for the hexapole-in-solenoid ECR ion source system. Under the appropriate radial confinement field, the smaller outer radius of hexapole can be better for the solenoid design. Saddle hexapole was selected by comparing the wire length, maximum outer radius of the hexapole, the Lorentz force at the end part of the hexapole and the maximum magnetic field in the coil. Based on saddle hexapole, a new design for hexapoles, the snake hexapole, was developed in this paper. By comparative analysis of the Lorentz force at the end part of the saddle and snake hexapoles, the snake hexapole is much better in the ECR ion source system. The suggested design for the ECR ion source with the snake hexapole is presented in this paper.

  9. The use of commercial thyristors in repetitive high voltage switching devices for plasma sources

    Science.gov (United States)

    Bac, J.; Reess, T.; Pecastaing, L.; Paillol, J.; Domens, P.

    2007-02-01

    This paper presents a commercial high voltage thyristor used as a switch allowing a tank capacitor to discharge in a load. In classical high power pulse technology applications the output voltage pulse has to be characterized mainly by its crest value, its rise-time, the period the thyristor is held in the on-state and the fall-time. These parameters are studied as a function of the power circuit and of the trigger circuit. The thyristor presents two behaviours: the main current is either higher or lower than the latching current. The “low current” behaviour is extensively investigated as it allows repetitive operation of the device. Two pulse power applications triggering electrical discharges are presented. Each one necessitates a specific pulsed power supply using series thyristor stacks or Marx structures. The first pulsed source delivers negative pulses with a crest voltage VoM=-35 kV, a turn on capability of Tr=90 ns and a repetition rate F=900 Hz. The second is built using Marx structure and is characterized by VoM=60 kV, Tr=250 ns, F=900 Hz.

  10. Development of core ion temperature gradients and edge sheared flows in a helicon plasma device investigated by laser induced fluorescence measurements

    Science.gov (United States)

    Thakur, S. C.; Gosselin, J. J.; McKee, J.; Scime, E. E.; Sears, S. H.; Tynan, G. R.

    2016-08-01

    We report experimental observation of ion heating and subsequent development of a prominent ion temperature gradient in the core of a linear magnetized plasma device, and the controlled shear de-correlation experiment. Simultaneously, we also observe the development of strong sheared flows at the edge of the device. Both the ion temperature and the azimuthal velocity profiles are quite flat at low magnetic fields. As the magnetic field is increased, the core ion temperature increases, producing centrally peaked ion temperature profiles and therefore strong radial gradients in the ion temperature. Similarly, we observe the development of large azimuthal flows at the edge, with increasing magnetic field, leading to strong radially sheared plasma flows. The ion velocities and temperatures are derived from laser induced fluorescence measurements of Doppler resolved velocity distribution functions of argon ions. These features are consistent with the previous observations of simultaneously existing radially separated multiple plasma instabilities that exhibit complex plasma dynamics in a very simple plasma system. The ion temperature gradients in the core and the radially sheared azimuthal velocities at the edge point to mechanisms that can drive the multiple plasma instabilities, that were reported earlier.

  11. A validation of the Experiences in Close Relationships-Relationship Structures scale (ECR-RS) in adolescents

    DEFF Research Database (Denmark)

    Donbaek, Dagmar Feddern; Elklit, Ask

    2014-01-01

    Emerging evidence points toward a two-dimensional attachment construct: avoidance and anxiety. The Experiences in Close Relationships-Relationship Structures scale (ECR-RS; Fraley, Heffernan, Vicary, & Brumbaugh, 2011) is a questionnaire assessing two-dimensional relationship-specific attachment...... structures in adults and, hence, moves beyond the traditional focus on romantic relationships. The present article explored the psychometric abilities of the ECR-RS across parental and best friend domains in a sample of 15 to 18-year-olds (n = 1999). Two oblique factors were revealed across domains......, exhibiting satisfactory construct validity, including factorspecific links to the model of adult attachment (Bartholomew & Horowitz, 1991), and independent factor discrimination between subgroups. A robust validation supports the application of the ECR-RS to assessing relationship-specific adolescent...

  12. Modelling of impurity transport and plasma-wall interaction in fusion devices with the ERO code: basics of the code and examples of application

    Energy Technology Data Exchange (ETDEWEB)

    Kirschner, A.; Borodin, D.; Brezinsek, S.; Linsmeier, C.; Romazanov, J. [Forschungszentrum Juelich GmbH, Institut fuer Energie- und Klimaforschung - Plasmaphysik, Juelich (Germany); Tskhakaya, D. [Fusion rate at OeAW, Institute of Applied Physics, TU Wien (Austria); Institute of Theoretical Physics, University of Innsbruck (Austria); Kawamura, G. [National Institute for Fusion Science, Gifu (Japan); Ding, R. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui (China)

    2016-08-15

    The 3D ERO code, which simulates plasma-wall interaction and impurity transport in magnetically confined fusion-relevant devices is described. As application, prompt deposition of eroded tungsten has been simulated at surfaces with shallow magnetic field of 3 T. Dedicated PIC simulations have been performed to calculate the characteristics of the sheath in front of plasma-exposed surfaces to use as input for these ERO simulations. Prompt deposition of tungsten reaches 100% at the highest electron temperature and density. In comparison to more simplified assumptions for the sheath the amount of prompt deposition is in general smaller if the PIC-calculated sheath is used. Due to friction with the background plasma the impact energy of deposited tungsten can be significantly larger than the energy gained in the sheath potential. (copyright 2016 The Authors. Contributions to Plasma Physics published by Wiley-VCH Verlag GmbH and Co. KGaA Weinheim. This)

  13. Platelet-rich plasma in the treatment of subcutaneous venous access device scars: a head-to-head patient survey.

    Science.gov (United States)

    Eichler, C; Najafpour, M; Sauerwald, A; Puppe, J; Warm, M

    2015-01-01

    Platelet-rich plasma (PRP) is a product widely used in sports medicine, tissue repair, and general surgery. A recent meta-analysis showed this product to be beneficial when introduced into a wound area, be it intra-articular (i.e., joint-injections) or direct introduction onto the wound surface. Between the years of 2012 and 2014 a questionnaire evaluating surgical outcome after port (venous access device) removal was answered by 100 patients in the control group and 20 patients in a PRP group, leading to a total of 120 patients in this single center, retrospective, subjective outcome evaluation. No statistical difference was shown in postsurgical complication rates, postsurgical pain, decreased mobility, and overall quality of life. A significant difference was shown in overall patient satisfaction and the desire to further improve port area scarring. Results differed significantly in favor of the PRP group. Interestingly, approximately 40.2% of patients are dissatisfied with the surgical outcome after port removal in the control group. This result, though surprising, may be improved to 10% dissatisfaction when a PRP product is used. PRP products such as Arthrex ACP are safe to use and present an additional option in improving surgical outcome.

  14. Platelet-Rich Plasma in the Treatment of Subcutaneous Venous Access Device Scars: A Head-to-Head Patient Survey

    Directory of Open Access Journals (Sweden)

    C. Eichler

    2015-01-01

    Full Text Available Introduction. Platelet-rich plasma (PRP is a product widely used in sports medicine, tissue repair, and general surgery. A recent meta-analysis showed this product to be beneficial when introduced into a wound area, be it intra-articular (i.e., joint-injections or direct introduction onto the wound surface. Methods. Between the years of 2012 and 2014 a questionnaire evaluating surgical outcome after port (venous access device removal was answered by 100 patients in the control group and 20 patients in a PRP group, leading to a total of 120 patients in this single center, retrospective, subjective outcome evaluation. Results. No statistical difference was shown in postsurgical complication rates, postsurgical pain, decreased mobility, and overall quality of life. A significant difference was shown in overall patient satisfaction and the desire to further improve port area scarring. Results differed significantly in favor of the PRP group. Interestingly, approximately 40.2% of patients are dissatisfied with the surgical outcome after port removal in the control group. This result, though surprising, may be improved to 10% dissatisfaction when a PRP product is used. Conclusion. PRP products such as Arthrex ACP are safe to use and present an additional option in improving surgical outcome.

  15. Material ejection and surface morphology changes during transient heat loading of tungsten as plasma-facing component in fusion devices

    Science.gov (United States)

    Suslova, A.; El-Atwani, O.; Harilal, S. S.; Hassanein, A.

    2015-03-01

    We investigated the effect of edge-localized mode like transient heat events on pristine samples for two different grades of deformed tungsten with ultrafine and nanocrystalline grains as potential candidates for plasma-facing components. Pulses from a laser beam with durations ∼1 ms and operating in the near infrared wavelength were used for simulating transient heat loading in fusion devices. We specifically focused on investigating and analysis of different mechanisms for material removal from the sample surface under repetitive transient heat loads. Several techniques were applied for analysing different mechanisms leading to material removal from the W surface under repetitive transient heat loads which include witness plates for collected ejected material, and subsequent analysis using x-ray photoelectron spectroscopy and scanning electron microscopy, visible imaging using fast-gated camera, and evaluating thermal emission from the particles using optical emission spectroscopy. Our results show a significantly improved performance of polycrystalline cold-rolled tungsten compared to tungsten produced using an orthogonal machining process under repetitive transient loads for a wide range of the power densities.

  16. Transport and emittance study for 18 GHz superconducting-ECR ion source at RCNP.

    Science.gov (United States)

    Yorita, T; Hatanaka, K; Fukuda, M; Ueda, H; Kibayashi, M; Morinobu, S; Tamii, A

    2012-02-01

    As the upgrade program of the azimuthally varying field (AVF) cyclotron is at the cyclotron facility of the RCNP, Osaka University for the improvement of the quality, stability, and intensity of accelerated beams, an 18 GHz superconducting (SC) ECR ion source has been installed to increase beam currents and to extend the variety of ions, especially for highly charged heavy ions which can be accelerated by RCNP AVF cyclotron. The production development of several ions such as B, O, N, Ne, Ar, Ni, Kr, and Xe has been performed by Yorita et al. [Rev. Sci. Instrum. 79, 02A311(2008); 81, 02A332 (2010)]. Further studies for the beam transport have been done in order to improve the beam current more for injection of cyclotron. The effect of field leakage of AVF main coil is not negligible and additional steering magnet has been installed and then beam transmission has been improved. The emittance monitor has also been developed for the purpose of investigating correlation between emittance of beam from ECR ion sources and injection efficiency. The monitor consists with BPM82 with rotating wire for fast measurement for efficient study.

  17. The effect of ion flux on plasma-induced modification and deuterium retention in tungsten and tungsten–tantalum alloys

    NARCIS (Netherlands)

    Zayachuk, Y.; Manhard, A.; Hoen, M. H. J. 't; Jacob, W.; van Emmichoven, P. A. Zeijlma; Van Oost, G.

    2015-01-01

    The paper presents the results of an experimental study of deuterium retention in W and W–Ta alloy that were exposed to first-wall relevant low flux (∼1020 m−2 s−1) deuterium plasma in the ECR plasma generator PlaQ. Subsequent analysis included surface imaging by optical

  18. PREFACE: 15th Latin American Workshop on Plasma Physics (LAWPP 2014) and 21st IAEA TM on Research Using Small Fusion Devices (RUSFD)

    Science.gov (United States)

    Iván Vargas-Blanco, V.; Herrera-Velázquez, J. Julio E.

    2015-03-01

    Written contributions from participants of the Joint 15th Latin American Workshop on Plasma Physics (LAWPP 2014) - 21st IAEA Technical Meeting on Research Using Small Fusion Devices (21st IAEA TM RUSFD). The International Advisory Committees of the 15th Latin American Workshop on Plasma Physics (LAWPP 2014) and the 21st IAEA TM on Research Using Small Fusion Devices (RUSFD), agreed to carry out together this Joint LAWPP 2014 - 21st RUSFD in San José, Costa Rica, on 27-31 January 2014. The Joint LAWPP 2014 - 21st RUSFD meeting, organized by the Instituto Tecnológico de Costa Rica, Universidad Nacional de Costa Rica, and Ad Astra Rocket Company in collaboration with the International Atomic Energy Agency (IAEA). The Latin American Workshop on Plasma Physics (LAWPP) is a series of events which has been held periodically since 1982, with the purpose of providing a forum in which the research of the Latin American plasma physics community can be displayed, as well as fostering collaborations among plasma scientists within the region and with researchers from the rest of the world. Recognized plasma scientists from developed countries are specially invited to the meeting to present the state of the art on several "hot" topics related to plasma physics. It is an open meeting, with an International Advisory Committee, in which the working language is English. It was firstly held in 1982 in Cambuquira, Brazil, followed by workshops in Medellín, Colombia (1985), Santiago de Chile, Chile (1988), Buenos Aires, Argentina (1990), Mexico City, Mexico (1992), Foz do Iguaçu, Brazil (1994, combined with the International Congress on Plasma Physics (ICPP)), Caracas, Venezuela (1997), Tandil, Argentina (1998), La Serena, Chile (2000), Sao Pedro, Brazil (2003), Mexico City, Mexico (2005), Caracas, Venezuela (2007), Santiago de Chile, Chile (2010, combined with the ICPP) and Mar de Plata, Argentina (2011). The 21st IAEA TM on Research Using Small Fusion Devices is an ideal forum for

  19. The Current Status of the Magnetoplasma Compressor Device in Belgrade – Study of Plasma Facing Materials Important for Fusion Reactors

    OpenAIRE

    Trklja, Nora

    2015-01-01

    The magnetoplasma compressor, a quasi stationary plasma accelerator, is a source of supersonic compression plasma flow. High plasma parameters of compression flow, large flow velocity and discharge duration enable their efficient usage for development of new plasma technologies, including material surface modification, creation of sub microstructures and nanostructures. In this paper spatial and temporal distribution of emissivity was studied using inverse Abel transform. This has been realiz...

  20. Enhanced highly charged ion production using a metal-dielectric liner in the KVI 14 GHz ECR ion source

    NARCIS (Netherlands)

    Schachter, L; Dobrescu, S; Rodrigues, G; Drentje, AG

    Forming on an aluminum surface a dielectric layer of alumina (aluminum oxide) in order to create a metal-dielectric (MD) structure increases the secondary-electron emission properties. The idea of using this material as a MD (Al-Al2O3) cylindrical liner inside an ECR ion source was previously tested

  1. MicroRNA-281 regulates the expression of ecdysone receptor (EcR) isoform B in the silkworm, Bombyx mori

    Science.gov (United States)

    Hundreds of Bombyx mori miRNAs had been identified in recent years, but their function in vivo remains poorly understood. The silkworm EcR gene (BmEcR) has three transcriptional isoforms, A, B1 and B2. Isoform sequences are different in the 3’UTR region of the gene, which is the case only in insects...

  2. Characterization of the Plasma Edge for Technique of Atomic Helium Beam in the CIEMAT Fusion Device; Caracterizacion del Borde del Plasma del Dispositivo de Fusion TJ-II del CIEMAT mediante el Diagnostico del Haz Supersonico de Helio

    Energy Technology Data Exchange (ETDEWEB)

    Hidalgo, A.

    2003-07-01

    In this report, the measurement of Electron Temperature and Density in the Boundary Plasma of TJ-II with a Supersonic Helium Beam Diagnostic and work devoted to the upgrading of this technique are described. Also, simulations of Laser Induced Fluorescence (LIF) studies of level populations of electronically excited He atoms are shown. This last technique is now being installed in the CIEMAT fusion device. (Author ) 36 refs.

  3. An evolutionary conserved region (ECR in the human dopamine receptor D4 gene supports reporter gene expression in primary cultures derived from the rat cortex

    Directory of Open Access Journals (Sweden)

    Haddley Kate

    2011-05-01

    Full Text Available Abstract Background Detecting functional variants contributing to diversity of behaviour is crucial for dissecting genetics of complex behaviours. At a molecular level, characterisation of variation in exons has been studied as they are easily identified in the current genome annotation although the functional consequences are less well understood; however, it has been difficult to prioritise regions of non-coding DNA in which genetic variation could also have significant functional consequences. Comparison of multiple vertebrate genomes has allowed the identification of non-coding evolutionary conserved regions (ECRs, in which the degree of conservation can be comparable with exonic regions suggesting functional significance. Results We identified ECRs at the dopamine receptor D4 gene locus, an important gene for human behaviours. The most conserved non-coding ECR (D4ECR1 supported high reporter gene expression in primary cultures derived from neonate rat frontal cortex. Computer aided analysis of the sequence of the D4ECR1 indicated the potential transcription factors that could modulate its function. D4ECR1 contained multiple consensus sequences for binding the transcription factor Sp1, a factor previously implicated in DRD4 expression. Co-transfection experiments demonstrated that overexpression of Sp1 significantly decreased the activity of the D4ECR1 in vitro. Conclusion Bioinformatic analysis complemented by functional analysis of the DRD4 gene locus has identified a a strong enhancer that functions in neurons and b a transcription factor that may modulate the function of that enhancer.

  4. Convective plasma stability consistent with MHD equilibrium in magnetic confinement systems with a decreasing field

    Science.gov (United States)

    Tsventoukh, M. M.

    2010-10-01

    A study is made of the convective (interchange, or flute) plasma stability consistent with equilibrium in magnetic confinement systems with a magnetic field decreasing outward and large curvature of magnetic field lines. Algorithms are developed which calculate convective plasma stability from the Kruskal-Oberman kinetic criterion and in which the convective stability is iteratively consistent with MHD equilibrium for a given pressure and a given type of anisotropy in actual magnetic geometry. Vacuum and equilibrium convectively stable configurations in systems with a decreasing, highly curved magnetic field are calculated. It is shown that, in convectively stable equilibrium, the possibility of achieving high plasma pressures in the central region is restricted either by the expansion of the separatrix (when there are large regions of a weak magnetic field) or by the filamentation of the gradient plasma current (when there are small regions of a weak magnetic field, in which case the pressure drops mainly near the separatrix). It is found that, from the standpoint of equilibrium and of the onset of nonpotential ballooning modes, a kinetic description of convective stability yields better plasma confinement parameters in systems with a decreasing, highly curved magnetic field than a simpler MHD model and makes it possible to substantially improve the confinement parameters for a given type of anisotropy. For the Magnetor experimental compact device, the maximum central pressure consistent with equilibrium and stability is calculated to be as high as β ˜ 30%. It is shown that, for the anisotropy of the distribution function that is typical of a background ECR plasma, the limiting pressure gradient is about two times steeper than that for an isotropic plasma. From a practical point of view, the possibility is demonstrated of achieving better confinement parameters of a hot collisionless plasma in systems with a decreasing, highly curved magnetic field than those

  5. Microwave plasma for materials treatment; Plasmas de microondas para tratamiento de materiales

    Energy Technology Data Exchange (ETDEWEB)

    Camps, E.; Garcia, J.L.; Muhl, S.; Alvarez F, O.; Chavez C, J. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    The microwave discharges of the Electron Cyclotron Resonance (Ecr) type are capable to generate plasma with relatively high ionization coefficients which can vary between 1 and 10 % also they are realized in low pressures at 10 {sup -4} Torr. order generating at this time high concentrations of neutral excited chemical species which result in that the chemical processes can be realized with much greater velocity as in another systems. In this work it was studied and characterized a microwave discharge type Ecr using for this electric probes and optical emission spectroscopy. The characterization was carried out with the purpose of optimizing the plasma parameters and to establish a control over the same one doing so that the experiments have a greater reproducibility and a major work efficiency. (Author)

  6. Flashback and perspectives for the production of intense ion beams with ECR ion sources

    Science.gov (United States)

    Gammino, S.; Ciavola, G.; Consoli, F.; Barbarino, S.; Celona, L.; Mascali, D.

    2005-10-01

    There is a clear evidence that the combination of ability to produce intense beams of highly charged heavy ions and of reliability, stability and low emittance can be guaranteed only by an adequate design of electron cyclotron resonance ion sources (ECRIS). Following the roadmap defined by Geller's scaling laws (1987) and the high B-mode concept (1990), the evolution of ECRIS has been steady and it amounted to about one order of magnitude per decade, as for high charge state currents. A further increase is possible according to the standard model of ECR sources unless technological problems may limit it in the future. Some sources are in the commissioning or construction phase to get the milliampere level for highly charged heavy ions, and some limitations have been already found but the possibility to get a further step forward remains unchanged. This paper presents the flashbacks of previous relevant experiences, along with the perspectives for higher current production in the years after 2010.

  7. High intensity metallic ion beam from an ecr ion source using the Mivoc method

    Energy Technology Data Exchange (ETDEWEB)

    Barue, C.; Canet, C.; Dupuis, M.; Flambard, J.L.; Leherissier, P.; Lemagnen, F. [Grand Accelerateur National d' Ions Lourds (GANIL), 14 - Caen (France); Jaffres, P.A. [Institut des Sciences de la Matiere et du Rayonnement, SIMRa, 14 - Cean (France)

    2000-07-01

    The MIVOC method has been successfully used at GANIL to produce a high intensity nickel beam with the ECR4 ion source: 20 {mu}A {sup 58}Ni{sup 11+} at 24 kV extraction voltage. This beam has been maintained for 8 days and accelerated up to 74.5 MeV/u by our cyclotrons with a mean intensity of 0.13 p{mu}A on target. This high intensity, required for experiment, led to the discovery of the doubly magic {sup 48}Ni isotope. Experimental setup, handling and off-line preparation using a residual gas analyzer are described in this report. The ion source behavior, performances and limitations are presented in the case of nickel and iron. The ionization efficiencies have been measured and compared to the oven method usually used at GANIL. (author)

  8. Protein-protein interface detection using the energy centrality relationship (ECR characteristic of proteins.

    Directory of Open Access Journals (Sweden)

    Sanjana Sudarshan

    Full Text Available Specific protein interactions are responsible for most biological functions. Distinguishing Functionally Linked Interfaces of Proteins (FLIPs, from Functionally uncorrelated Contacts (FunCs, is therefore important to characterizing these interactions. To achieve this goal, we have created a database of protein structures called FLIPdb, containing proteins belonging to various functional sub-categories. Here, we use geometric features coupled with Kortemme and Baker's computational alanine scanning method to calculate the energetic sensitivity of each amino acid at the interface to substitution, identify hotspots, and identify other factors that may contribute towards an interface being FLIP or FunC. Using Principal Component Analysis and K-means clustering on a training set of 160 interfaces, we could distinguish FLIPs from FunCs with an accuracy of 76%. When these methods were applied to two test sets of 18 and 170 interfaces, we achieved similar accuracies of 78% and 80%. We have identified that FLIP interfaces have a stronger central organizing tendency than FunCs, due, we suggest, to greater specificity. We also observe that certain functional sub-categories, such as enzymes, antibody-heavy-light, antibody-antigen, and enzyme-inhibitors form distinct sub-clusters. The antibody-antigen and enzyme-inhibitors interfaces have patterns of physical characteristics similar to those of FunCs, which is in agreement with the fact that the selection pressures of these interfaces is differently evolutionarily driven. As such, our ECR model also successfully describes the impact of evolution and natural selection on protein-protein interfaces. Finally, we indicate how our ECR method may be of use in reducing the false positive rate of docking calculations.

  9. Properties of highly electronegative plasmas produced in a multipolar magnetic-confined device with a transversal magnetic filter

    DEFF Research Database (Denmark)

    Draghici, Mihai; Stamate, Eugen

    2010-01-01

    electrodes on plasma parameters, the formation of the negative ion sheath and etching rates by positive and negative ions have been investigated for different experimental conditions. When the electron temperature was reduced below 1 eV the density ratio of negative ion to electron exceeded 100 even for very...... low amounts of SF6 gas. The plasma potential drift could be controlled by proper wall conditioning. A large electrode biased positively had no effect on plasma potential for density ratios of negative ions to electrons larger than 50. For similar electronegativities or higher a negative ion sheath......Highly electronegative plasmas were produced in Ar/SF6 gas mixtures in a dc discharge with multipolar magnetic confinement and transversal magnetic filter. Langmuir probe and mass spectrometry were used for plasma diagnostics. Plasma potential drift, the influence of small or large area biased...

  10. Low-noise AlGaAs/InGaAs/GaAs pseudomorphic high electron mobility transistor recessed by electron cyclotron resonance plasma etching

    CERN Document Server

    Lee, J H; Lee, C W; Yoon, H S; Park, B S; Park, C S

    1999-01-01

    GaAs pseudomorphic high electron mobility transistor recessed by electron cyclotron resonance (ECR) plasma etching have been investigated. We used a BCl sub 3 /SF sub 6 gas mixture to implement the gate recess process. We obtained a uniformity of the threshold voltage to within 50 mV in 3-inch wafers. The GaAs PHEMTs with a 0.2-mu m gate length recessed by the ECR plasma exhibited a minimum noise figure (NF sub m sub i sub n) as low as 0.26 dB with an associated gain (G sub a) of 13 dB at 12 GHz. At 18 GHz, the NF sub m sub i sub n was 0.47 dB with a Ga of 11.66 dB. These results suggest that the ECR plasma etching process reported here is suitable as a manufacturing process for gate recess of a GaAs PHEMT.

  11. Effects of Electron-Cyclotron-Resonance Oxygen Plasma Irradiation on Properties of Insulator/Ge-Semiconductor Interfaces Prior to Germanium Nitride Formation

    Science.gov (United States)

    Otani, Yohei; Fukuda, Yukio; Sato, Tetsuya; Nakagawa, Kiyokazu; Toyota, Hiroshi; Ono, Toshiro

    2008-09-01

    Electron-cyclotron-resonance (ECR) oxygen (O2) plasma was irradiated onto the surface of germanium (Ge) substrates prior to germanium nitride (GeNx) formation. Germanium metal-insulator-semiconductor (Ge-MIS) structures with a 5-nm-thick silicon nitride/2-nm-thick GeNx gate insulator stack fabricated by ECR plasma nitridation and sputtering deposition without substrate heating were electrically and physically characterized. Although ECR O2 plasma irradiation onto the surface of Ge substrates caused no significant difference in the chemical state of GeNx/Ge interfaces in X-ray photoemission spectroscopic measurement, irradiation for an appropriate period improved the state of GeNx/Ge interfaces and the electrical properties of Ge-MIS.

  12. Liquid metals as a divertor plasma-facing material explored using the Pilot-PSI and Magnum-PSI linear devices

    Science.gov (United States)

    Morgan, T. W.; Rindt, P.; van Eden, G. G.; Kvon, V.; Jaworksi, M. A.; Lopes Cardozo, N. J.

    2018-01-01

    For DEMO and beyond, liquid metal plasma-facing components are considered due to their resilience to erosion through flowed replacement, potential for cooling beyond conduction and inherent immunity to many of the issues of neutron loading compared to solid materials. The development curve of liquid metals is behind that of e.g. tungsten however, and tokamak-based research is currently somewhat limited in scope. Therefore, investigation into linear plasma devices can provide faster progress under controlled and well-diagnosed conditions in assessing many of the issues surrounding the use of liquid metals. The linear plasma devices Magnum-PSI and Pilot-PSI are capable of producing DEMO-relevant plasma fluxes, which well replicate expected divertor conditions, and the exploration of physics issues for tin (Sn) and lithium (Li) such as vapour shielding, erosion under high particle flux loading and overall power handling are reviewed here. A deeper understanding of erosion and deposition through this work indicates that stannane formation may play an important role in enhancing Sn erosion, while on the other hand the strong hydrogen isotope affinity reduces the evaporation rate and sputtering yields for Li. In combination with the strong redeposition rates, which have been observed under this type of high-density plasma, this implies that an increase in the operational temperature range, implying a power handling range of 20–25 MW m‑2 for Sn and up to 12.5 MW m‑2 for Li could be achieved. Vapour shielding may be expected to act as a self-protection mechanism in reducing the heat load to the substrate for off-normal events in the case of Sn, but may potentially be a continual mode of operation for Li.

  13. Characterization and modelling of microwave multi dipole plasmas. Application to multi dipolar plasma assisted sputtering; Caracterization et modelisation des plasmas micro-onde multi-dipolaires. Application a la pulverisation assistee par plasma multi-dipolaire

    Energy Technology Data Exchange (ETDEWEB)

    Tran, Tan Vinh [Universite Joseph Fourier/CNRS-IN2P3, 53 Avenue des Martyrs, F-38026 Grenoble (France)

    2006-07-01

    The scaling up of plasma processes in the low pressure range remains a question to be solved for their rise at the industrial level. One solution is the uniform distribution of elementary plasma sources where the plasma is produced via electron cyclotron resonance (ECR) coupling. These elementary plasma sources are made up of a cylindrical permanent magnet (magnetic dipole) set at the end of a coaxial microwave line. Although of simple concept, the optimisation of these dipolar plasma sources is in fact a complex problem. It requires the knowledge, on one hand, of the configurations of static magnetic fields and microwave electric fields, and, on the other hand, of the mechanisms of plasma production in the region of high intensity magnetic field (ECR condition), and of plasma diffusion. Therefore, the experimental characterisation of the operating ranges and plasma parameters has been performed by Langmuir probes and optical emission spectroscopy on different configurations of dipolar sources. At the same time, in a first analytical approach, calculations have been made on simple magnetic field configurations, motion and trajectory of electrons in these magnetic fields, and the acceleration of electrons by ECR coupling. Then, the results have been used for the validation of the numerical modelling of the electron trajectories by using a hybrid PIC (particle-in-cell) / MC (Monte Carlo) method. The experimental study has evidenced large operating domains, between 15 and 200 W of microwave power, and from 0.5 to 15 mTorr argon pressure. The analysis of plasma parameters has shown that the region of ECR coupling is localised near the equatorial plane of the magnet and dependent on magnet geometry. These characterizations, applied to a cylindrical reactor using 48 sources, have shown that densities between 10{sup 11} and 10{sup 12} cm{sup -3} could be achieved in the central part of the volume at a few mTorr argon pressures. The modelling of electron trajectories near

  14. Detection efficiency vs. cathode and anode separation in cylindrical vacuum photodiodes used for measuring x-rays from plasma focus device

    Science.gov (United States)

    Borthakur, T. K.; Talukdar, N.; Neog, N. K.; Rao, C. V. S.; Shyam, A.

    2011-10-01

    A qualitative study on the performance of cylindrical vacuum photodiodes (VPDs) for x-ray detection in plasma focus device has been carried out. Various parameters of VPD such as electrode's diameter, electrode's separation, and its sensitivity are experimentally tested in plasma focus environment. For the first time it is found experimentally that the electrode-separation in the lateral direction of the two coaxial electrodes of cylindrical VPD also plays an important role to increase the efficiency of the detector. The efficiency is found to be highest for the detector with smaller cathode-anode lateral gap (1.5 mm) with smaller photo cathode diameter (10 mm). A comparison between our VPD with PIN (BPX-65) diode as an x-ray detector has also been made.

  15. Lowering of L1{sub 0} phase transition temperature of FePt thin films by single shot H{sup +} ion exposure using plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Z.Y.; Lin, J.J. [NSSE, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616 (Singapore); Zhang, T. [School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore); Karamat, S.; Tan, T.L.; Lee, P.; Springham, S.V. [NSSE, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616 (Singapore); Ramanujan, R.V. [School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore); Rawat, R.S. [NSSE, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616 (Singapore)], E-mail: rajdeep.rawat@nie.edu.sg

    2009-02-27

    FePt thin films are exposed to pulsed energetic H{sup +} ion beam from plasma focus. In irradiated films, the phase transition from the low K{sub u} disordered face-centered-cubic structure to high K{sub u} ordered face-centered-tetragonal phase was achieved at 400 deg. C with the order parameter S ranging from 0.73 to 0.83, high coercivity of about 5356 kA/m, high negative nucleation field of about 7700 kA/m and high squareness ratio ranging from 0.73 to 0.79. The advantage of using plasma focus device is that it can lower phase transition temperature and significantly enhance the magnetic properties by a pulsed single shot exposure.

  16. Experimental results on hard x-ray energy emitted by a low-energy plasma focus device: a radiographic image analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zambra, Marcelo; Pavez, Cristian; Pasten, Denisse; Moreno, Jose; Soto, Leopoldo [Comision Chilena de EnergIa Nuclear, Amunategui 95, PO Box 188-D, Santiago (Chile); Silva, Patricio, E-mail: mzambra@cchen.c

    2009-12-15

    The PF-400J plasma focus device (400 J of energy) was studied in a similar way to a pulsed source of high-energy x-ray radiation. High-sensitivity fast-response commercial radiographic film and different metal filter array combinations were used to study the energy of the proper emitted x-ray. The effective energy of the hard x-ray radiation is studied and discussed in terms of its effective mean attenuation with the penetration distance on different metallic samples when the x-ray pulsed beam is supposed monoenergetic. These results were then used to assess the energetic properties of the pulsed radiation when different x-ray film-filter array combinations were irradiated between tens to almost 160 effective pulses of x-ray coming from the PF-400J device.

  17. Experimental results on hard x-ray energy emitted by a low-energy plasma focus device: a radiographic image analysis

    Science.gov (United States)

    Zambra, Marcelo; Silva, Patricio; Pavez, Cristian; Pasten, Denisse; Moreno, José; Soto, Leopoldo

    2009-12-01

    The PF-400J plasma focus device (400 J of energy) was studied in a similar way to a pulsed source of high-energy x-ray radiation. High-sensitivity fast-response commercial radiographic film and different metal filter array combinations were used to study the energy of the proper emitted x-ray. The effective energy of the hard x-ray radiation is studied and discussed in terms of its effective mean attenuation with the penetration distance on different metallic samples when the x-ray pulsed beam is supposed monoenergetic. These results were then used to assess the energetic properties of the pulsed radiation when different x-ray film-filter array combinations were irradiated between tens to almost 160 effective pulses of x-ray coming from the PF-400J device.

  18. Improvement of plasma energy confinement in tokamak under radiative cooling of the edge plasma

    Science.gov (United States)

    Razumova, K. A.; Borschegovskiy, A. A.; Gorbunov, E. P.; Dremin, M. M.; Kasyanova, N. V.; Kirneva, N. A.; Kislov, A. Ya.; Klyuchnikov, L. A.; Krupin, V. A.; Krylov, S. V.; Lysenko, S. E.; Melnikov, A. V.; Myalton, T. B.; Nemets, A. R.; Notkin, G. E.; Nurgaliev, M. R.; Sarychev, D. V.; Sushkov, A. V.; Chistyakov, V. V.; Ongena, J.; Messiaen, A.

    2017-11-01

    Improvement of plasma energy confinement in the T-10 tokamak by injection of impurity gases was studied experimentally. Injection of Ne and He in the ohmic and ECR heating regimes allows one to separate the dependences of energy confinement on the plasma density and on the edge plasma cooling rate. It is shown that the well-known dependence of the energy confinement time on the plasma density is, in fact, the dependence on the radiative loss power. This phenomenon can be explained by plasma self-organization. The experiments are described by a thermodynamic model for self-organized plasma in which the transport coefficient depends on the difference between the actual and self-consistent pressure profiles. The reduction in the heat flux at the plasma edge due to radiative cooling leads to a decrease in the transport coefficient in this region and, accordingly, improves energy confinement. Results of approximate model calculations for experiments with Ne injection are presented.

  19. Initial Results of Optical Vortex Laser Absorption Spectroscopy in the HYPER-I Device

    Science.gov (United States)

    Yoshimura, Shinji; Asai, Shoma; Aramaki, Mitsutoshi; Terasaka, Kenichiro; Ozawa, Naoya; Tanaka, Masayoshi; Morisaki, Tomohiro

    2015-11-01

    Optical vortex beams have a potential to make a new Doppler measurement, because not only parallel but perpendicular movement of atoms against the beam axis causes the Doppler shift of their resonant absorption frequency. As the first step of a proof-of-principle experiment, we have performed the optical vortex laser absorption spectroscopy for metastable argon neutrals in an ECR plasma produced in the HYPER-I device at the National Institute for Fusion Science, Japan. An external cavity diode laser (TOPTICA, DL100) of which center wavelength was 696.735 nm in vacuum was used for the light source. The Hermite-Gaussian (HG) beam was converted into the Laguerre-Gaussian (LG) beam (optical vortex) by a computer-generated hologram displayed on the spatial light modulator (Hamamatsu, LCOS-SLM X10468-07). In order to make fast neutral flow across the LG beam, a high speed solenoid valve system was installed on the HYPER-I device. Initial results including the comparison of absorption spectra for HG and LG beams will be presented. This study was supported by NINS young scientists collaboration program for cross-disciplinary study, NIFS collaboration research program (NIFS13KOAP026), and JSPS KAKENHI grant number 15K05365.

  20. Development and validation of a new method to simultaneously quantify triazoles in plasma spotted on dry sample spot devices and analysed by HPLC-MS.

    Science.gov (United States)

    Baietto, Lorena; D'Avolio, Antonio; Marra, Cristina; Simiele, Marco; Cusato, Jessica; Pace, Simone; Ariaudo, Alessandra; De Rosa, Francesco Giuseppe; Di Perri, Giovanni

    2012-11-01

    Therapeutic drug monitoring (TDM) of triazoles is widely used in clinical practice to optimize therapy. TDM is limited by technical problems and cost considerations, such as sample storage and dry-ice shipping. We aimed to develop and validate a new method to analyse itraconazole, posaconazole and voriconazole in plasma spotted on dry sample spot devices (DSSDs) and to quantify them by an HPLC system. Extraction from DSSDs was done using n-hexane/ethyl acetate and ammonia solution. Samples were analysed using HPLC with mass spectrometry (HPLC-MS). Accuracy and precision were assayed by inter- and intra-day validation. The stability of triazoles in plasma spotted on DSSDs was investigated at room temperature for 1 month. The method was compared with a validated standard HPLC method for quantification of triazoles in human plasma. Mean inter- and intra-day accuracy and precision were method was linear (r(2) > 0.999) in the range 0.031-8 mg/L for itraconazole and posaconazole, and 0.058-15 mg/L for voriconazole. High sensitivity was observed; limits of detection were 0.008, 0.004 and 0.007 mg/L for itraconazole, posaconazole and voriconazole, respectively. A high degree of correlation (r(2) > 0.94) was obtained between the DSSD method and the standard method of analysis. The method that we developed and validated to quantify triazoles in human plasma spotted on DSSDs is accurate and precise. It overcomes problems related to plasma sample storage and shipment, allowing TDM to be performed in a cheaper and safer manner.

  1. US/ECRE and renewable energy market development: An institutional perspective

    Energy Technology Data Exchange (ETDEWEB)

    Siegel, J.M.

    1997-12-01

    The author presents a summary of the structure and program of the US Export Council for Renewable Energy (US/ECRE). This organization was founded in 1982 as a consortium of US renewable energy trade associations, and is the non-profit/industry counterpart of CORECT. It serves to accelerate the diffusion of sustainable renewable energy services worldwide, and to enhance US industry`s position in this expanded marketplace. The projected energy growth in the next 20 years is expected to favor developing countries. Barriers in the way of renewable energy development include technology awareness, financing and risk reception, policy decisions, and institutional barriers. The industrial team hopes to address this problem through several different programs: strategic alliances; end-user outreach; industry market development; policy/project development; financing and facilitation. The program involves several phases: first, market conditioning; second, regional conferences and exhibitions; third, follow-up and implementation. There are currently four major focus areas for US effort: Latin America and the Caribbean; southern Africa; Asia; Russia and the FSU. The status of programs addressed toward these markets is described in more detail.

  2. Injection of auxiliary electrons for increasing the plasma density in highly charged and high intensity ion sources.

    Science.gov (United States)

    Odorici, F; Malferrari, L; Montanari, A; Rizzoli, R; Mascali, D; Castro, G; Celona, L; Gammino, S; Neri, L

    2016-02-01

    Different electron guns based on cold- or hot-cathode technologies have been developed since 2009 at INFN for operating within ECR plasma chambers as sources of auxiliary electrons, with the aim of boosting the source performances by means of a higher plasma lifetime and density. Their application to microwave discharge ion sources, where plasma is not confined, has required an improvement of the gun design, in order to "screen" the cathode from the plasma particles. Experimental tests carried out on a plasma reactor show a boost of the plasma density, ranging from 10% to 90% when the electron guns are used, as explained by plasma diffusion models.

  3. Work function tuning of plasma-enhanced atomic layer deposited WC{sub x}N{sub y} electrodes for metal/oxide/semiconductor devices

    Energy Technology Data Exchange (ETDEWEB)

    Zonensain, Oren; Fadida, Sivan; Eizenberg, Moshe [Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Fisher, Ilanit; Gao, Juwen; Chattopadhyay, Kaushik; Harm, Greg; Mountsier, Tom; Danek, Michal [Lam Research Corporation, 4000 N. First Street, San Jose, California 95134 (United States)

    2015-02-23

    One of the main challenges facing the integration of metals as gate electrodes in advanced MOS devices is control over the Fermi level position at the metal/dielectric interface. In this study, we demonstrate the ability to tune the effective work function (EWF) of W-based electrodes by process modifications of the atomic layer deposited (ALD) films. Tungsten carbo-nitrides (WC{sub x}N{sub y}) films were deposited via plasma-enhanced and/or thermal ALD processes using organometallic precursors. The process modifications enabled us to control the stoichiometry of the WC{sub x}N{sub y} films. Deposition in hydrogen plasma (without nitrogen based reactant) resulted in a stoichiometry of WC{sub 0.4} with primarily W-C chemical bonding, as determined by x-ray photoelectron spectroscopy. These films yielded a relatively low EWF of 4.2 ± 0.1 eV. The introduction of nitrogen based reactant to the plasma or the thermal ALD deposition resulted in a stoichiometry of WC{sub 0.1}N{sub 0.6–0.8} with predominantly W-N chemical bonding. These films produced a high EWF of 4.7 ± 0.1 eV.

  4. Achievement of field-reversed configuration plasma sustainment via 10 MW neutral-beam injection on the C-2U device

    Science.gov (United States)

    Gota, H.; Binderbauer, M. W.; Tajima, T.; Putvinski, S.; Tuszewski, M.; Dettrick, S.; Garate, E.; Korepanov, S.; Smirnov, A.; Thompson, M. C.; Trask, E.; Yang, X.; Schmitz, L.; Lin, Z.; Ivanov, A. A.; Asai, T.; Allfrey, I.; Andow, R.; Beall, M.; Bolte, N.; Bui, D. Q.; Cappello, M.; Ceccherini, F.; Clary, R.; Cheung, A. H.; Conroy, K.; Deng, B. H.; Douglass, J.; Dunaevsky, A.; Feng, P.; Fulton, D.; Galeotti, L.; Granstedt, E.; Griswold, M.; Gupta, D.; Gupta, S.; Hubbard, K.; Isakov, I.; Kinley, J. S.; Knapp, K.; Magee, R.; Matvienko, V.; Mendoza, R.; Mok, Y.; Necas, A.; Primavera, S.; Onofri, M.; Osin, D.; Rath, N.; Roche, T.; Romero, J.; Schindler, T.; Schroeder, J. H.; Sevier, L.; Sheftman, D.; Sibley, A.; Song, Y.; Steinhauer, L. C.; Valentine, T.; Van Drie, A. D.; Walters, J. K.; Waggoner, W.; Yushmanov, P.; Zhai, K.; The TAE Team

    2017-11-01

    Tri Alpha Energy’s experimental program has demonstrated reliable field-reversed configuration (FRC) formation and sustainment, driven by fast ions via high-power neutral-beam (NB) injection. The world’s largest compact-toroid device, C-2U, was upgraded from C-2 with the following key system upgrades: increased total NB input power from ~4 MW (20 keV hydrogen) to 10+  MW (15 keV hydrogen) with tilted injection angle; enhanced edge-biasing capability inside of each end divertor for boundary/stability control. C-2U experiments with those upgraded systems have successfully demonstrated dramatic improvements in FRC performance and achieved sustainment of advanced beam-driven FRCs with a macroscopically stable and hot plasma state for up to 5+  ms. Plasma diamagnetism in the best discharges has reached record lifetimes of over 11 ms, timescales twice as long as C-2. The C-2U plasma performance, including the sustainment feature, has a strong correlation with NB pulse duration, with the diamagnetism persisting even several milliseconds after NB termination due to the accumulated fast-ion population by NB injection. Power balance analysis shows substantial improvements in equilibrium and transport parameters, whereby electron energy confinement time strongly correlates with electron temperature; i.e. the confinement time in C-2U scales strongly with a positive power of T e.

  5. Adhesion of Pseudomonas aeruginosa strains to untreated and oxygen-plasma treated poly(vinyl chloride) (PVC) from endotracheal intubation devices.

    Science.gov (United States)

    Triandafillu, K; Balazs, D J; Aronsson, B-O; Descouts, P; Tu Quoc, P; van Delden, C; Mathieu, H J; Harms, H

    2003-04-01

    Pseudomonas aeruginosa pneumonia is a life threatening complication in mechanically ventilated patients that requires the ability of the bacteria to adhere to, and colonize the endotracheal intubation device. New strategies to prevent or reduce these nosocomial infections are greatly needed. We report here the study of a set of P. aeruginosa clinical isolates, together with specific mutants, regarding their adhesion on native and chemically modified poly(vinyl chloride) (PVC) surfaces from endotracheal intubation devices. The adhesion of the different strains to untreated PVC varied widely, correlating with several physico-chemical characteristics known to influence the attachment of bacteria to inert surfaces. The adhesion patterns were compared to the calculations obtained with the DLVO theory of colloidal stability. These results illustrate the importance of testing different clinical isolates when investigating bacterial adhesion. Oxygen plasma treatment of the PVC pieces yielded a hydrophilic surface and reduced the number of adhering bacteria by as much as 70%. This reduction is however unlikely to be sufficient to prevent P. aeruginosa colonization of endotracheal intubation devices. Copyright 2002 Elsevier Science Ltd.

  6. Application of atmospheric solution precursor plasma spray to photocatalytic devices for small and medium industries in developing countries

    Science.gov (United States)

    Kindole, Dickson; Ando, Yasutaka

    2017-01-01

    For development of a functional film deposition process with high deposition rate, as a basic study, TiO2 films were deposited by atmospheric solution precursor plasma spray (ASPPS) process. Ethanol-diluted titanium tetraisobutoxide [TTIB: Ti(OC4H9)4] was used as a feedstock. To achieve a high plasma thermal energy at a low discharge power, N2-dominant Ar/N2 as the plasma working gas was used, for film deposition at various deposition distances. Consequently, photocatalytic TiO2 with a rutile/anatase mixture film structure was deposited evenly in this case. By conducting methylene blue decomposition and wettability tests, photocatalytic properties of the film were confirmed. When a TiO2 film was applied to photocatalytic dye-sensitized solar cells (DSSCs), the cells generated an electromotive force of 0.143V oc, which is close to those of commercial DSSCs. From these results, the ASPPS process was found to have high potential for high rate functional film deposition and was cost effective, making it suitable for developing countries.

  7. The effectiveness of riboflavin photochemical-mediated virus inactivation and changes in protein retention in fresh-frozen plasma treated using a flow-based treatment device.

    Science.gov (United States)

    Zhu, Liguo; Pan, Jichun; Wei, Chao; Wang, Haibao; Xiang, Rong; Zhang, Jingang; Wang, Deqing

    2015-01-01

    A flow-based treatment device using riboflavin and ultraviolet (UV) light was developed to inactivate viruses in fresh-frozen plasma (FFP). The objective of this study was to evaluate the in vitro effectiveness of virus inactivation and changes in protein quality in FFP treated with this device. FFP-contaminating viruses were treated with riboflavin and UV light using a one-pass linear flow device. The infectivity of viruses was measured using established biologic assays. Real-time polymerase chain reaction (PCR) was performed to detect damage to viral nucleotides after treatment. Treated plasma was analyzed using standard coagulation assays. FFP treated at the UV dose of 3.6 J/cm(2) (J) exhibited a mean reduction of virus titer of more than 4 logs. The effectiveness increased significantly at higher doses. Real-time PCR showed that the cycle threshold values for both complete inactivation and virus recultivation were higher than that of the untreated sample. At doses of 3.6, 5.4, and 7.2 J, the protein recovery rates were 60.2 ± 8.6, 46.6 ± 9.4, and 28.0 ± 1.0% for fibrinogen; 67.0 ± 3.1, 57.3 ± 8.0, and 49.2 ± 3.8% for Factor VIII; 93.6 ± 2.8, 89.6 ± 6.1, and 86.5 ± 5.3% for antithrombin-III; and 72.1 ± 5.6, 59.8 ± 14.2, and 49.2 ± 8.4% for Protein C, respectively. The effectiveness of virus inactivation was enhanced, but total activity of plasma factors was reduced, in a UV dose-dependent manner. © 2014 The Authors. Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

  8. Active particle control experiments and critical particle flux discriminating between the wall pumping and fuelling in the compact plasma wall interaction device CPD spherical tokamak

    Science.gov (United States)

    Zushi, H.; Hirooka, Y.; Bhattacharyay, R.; Sakamoto, M.; Nakashima, Y.; Yoshinaga, T.; Higashizono, Y.; Hanada, K.; Nishino, N.; Yoshida, N.; Tokunaga, K.; Kado, S.; Shikama, T.; Kawasaki, S.; Okamoto, K.; Miyazaki, T.; Honma, H.; Sato, K. N.; Nakamura, K.; Idei, H.; Hasegawa, M.; Nakashima, H.; Higashijima, A.

    2009-05-01

    Two approaches associated with wall recycling have been performed in a small spherical tokamak device CPD (compact plasma wall interaction experimental device), that is, (1) demonstration of active particle recycling control, namely, 'active wall pumping' using a rotating poloidal limiter whose surface is continuously gettered by lithium and (2) a basic study of the key parameters which discriminates between 'wall pumping and fuelling'. For the former, active control of 'wall pumping' has been demonstrated during 50 kW RF current drive discharges whose pulse length is typically ~300 ms. Although the rotating limiter is located at the outer board, as soon as the rotating drum is gettered with lithium, hydrogen recycling measured with Hα spectroscopy decreases by about a factor of 3 not only near the limiter but also in the centre stack region. Also, the oxygen impurity level measured with O II spectroscopy is reduced by about a factor of 3. As a consequence of the reduced recycling and impurity level, RF driven current has nearly doubled at the same vertical magnetic field. For the latter, global plasma wall interaction with plasma facing components in the vessel is studied in a simple torus produced by electron cyclotron waves with Ip static gas balance (pressure measurement) without external pumping systems has been performed to investigate the role of particle flux on a transition of 'wall fuelling' to 'wall pumping'. It is found that a critical particle flux exists to discriminate between them. Beyond the critical value, a large fraction (~80%) of pressure drop ('wall pumping') is found, suggesting that almost all injected particles are retained in the wall. Below it, a significant pressure rise ('wall fuelling') is found, which indicates that particles are fuelled from the wall during/just after the discharge. Shot history effects (integrated particle recycling behaviour from the plasma facing surfaces) are seen on that the critical particle flux is reducing

  9. 21 CFR 866.2160 - Coagulase plasma.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Coagulase plasma. 866.2160 Section 866.2160 Food... DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2160 Coagulase plasma. (a) Identification. Coagulase plasma is a device that consists of freeze-dried animal or human plasma that is...

  10. Study of Shock Wave and Magnetic Pressure Effects on the Rail Gap Switch Surface Used at the APF Plasma Focus Device

    Science.gov (United States)

    Habibi, Morteza

    2011-04-01

    Whereas high voltage and current create a rough environment for switch electrodes in pulse power technology, the switch requires the most maintenance or replacement after a short time. In this paper we investigate the effects of magnetic and shock pressures created by high power electric arc between a rail gap switch with copper electrodes at the APF plasma focus device. As studied by others, the shock pressure is some order of magnitude higher than the magnetic pressure after electric arc generation. We calculated the magnetic pressure, electric arc radius, time dependent arc velocity, and also time dependent shock pressure created by an oscillating current discharge applied across the rail gap electrodes surface. Modeling included a MathCAD analysis of the diverging wave front through the electrode and the results show that the shock wave pressure induced after the electric arc has a serious destructive effect on our switch surface.

  11. Tungsten as a plasma-facing material in fusion devices: impact of helium high-temperature irradiation on hydrogen retention and damages in the material

    Science.gov (United States)

    Bernard, E.; Sakamoto, R.; Kreter, A.; Barthe, M. F.; Autissier, E.; Desgardin, P.; Yamada, H.; Garcia-Argote, S.; Pieters, G.; Chêne, J.; Rousseau, B.; Grisolia, C.

    2017-12-01

    Plasma-facing materials for next generation fusion devices, like ITER and DEMO, have to withstand intense fluxes of light elements (notably helium and hydrogen isotopes). For tungsten (W), helium (He) irradiation leads to major changes in the material morphology, rising concerns about properties such as material structure conservation and hydrogen (H) retention. The impact of preceeding He irradiation conditions (temperature, flux and fluence) on H trapping were investigated on a set of W samples exposed to the linear plasma device PSI-2. Positron annihilation spectroscopy (PAS) was carried out to probe the free volume of defects created by the He exposure in the W structure at the atomic scale. In parallel, tritium (T) inventory after exposure was evaluated through T gas loading and desorption at the Saclay Tritium Lab. First, we observed that the material preparation prior to He irradiation was crucial, with a major reduction of the T trapping when W was annealed at 1773 K for 2 h compared to the as-received material. PAS study confirms the presence of He in the bubbles created in the material surface layer, whose dimensions were previously characterized by transmission electron microscopy and grazing-incidence small-angle x-ray scattering, and demonstrates that even below the minimal energy for displacement of He in W, defects are created in almost all He irradiation conditions. The T loading study highlights that increasing the He fluence leads to higher T inventory. Also, for a given fluence, increasing the He flux reduces the T trapping. The very first steps of a parametric study were set to understand the mechanisms at stake in those observed material modifications, confirming the need to pursue the study with a more complete set of surface and irradiation conditions.

  12. Electron cyclotron resonance plasma reactor for production of carbon stripper foil

    Science.gov (United States)

    Faith Romero, Camille; Kanamori, Keita; Kinsho, Michikazu; Yoshimoto, Masahiro; Wada, Motoi

    2018-01-01

    A graphite antenna for the production of carbon-containing hydrogen plasmas is being developed to prepare impurity-free charge exchange foils for high-energy synchrotrons. Microwave power at 2.45 GHz frequency drives a coaxial structure antenna with a 12-mm-diameter central graphite cylinder and a tapered surrounding cylinder serving as the ground electrode. The antenna was placed in a linear magnetic field to investigate how it performs under an electron cyclotron resonance (ECR) condition. A clear resonance phenomenon was observed in plasma luminosity, microwave power absorption, and microwave power reflection when the induction current used to produce a linear magnetic field was changed. The antenna realized the best microwave coupling to the plasma with the ECR zone formed 5 mm from the end of the center electrode. The antenna realized stable operation for more than 5 h with 100 W input microwave power and with operating hydrogen pressure from 0.5 to 50 Pa.

  13. Niobium thin film coating on a 500-MHz copper cavity by plasma deposition

    Energy Technology Data Exchange (ETDEWEB)

    Haipeng Wang; Genfa Wu; H. Phillips; Robert Rimmer; Anne-Marie Valente; Andy Wu

    2005-05-16

    A system using an Electron Cyclotron Resonance (ECR) plasma source for the deposition of a thin niobium film inside a copper cavity for superconducting accelerator applications has been designed and is being constructed. The system uses a 500-MHz copper cavity as both substrate and vacuum chamber. The ECR plasma will be created to produce direct niobium ion deposition. The central cylindrical grid is DC biased to control the deposition energy. This paper describes the design of several subcomponents including the vacuum chamber, RF supply, biasing grid and magnet coils. Operational parameters are compared between an operating sample deposition system and this system. Engineering work progress toward the first plasma creation will be reported here.

  14. Ultrathin oxide grown on polysilicon by using an electron cyclotron resonance N sub 2 O plasma

    CERN Document Server

    Han, S Y

    2000-01-01

    We have developed a process for growing ultrathin oxide on a polysilicon layer by using an electron cyclotron resonance (ECR) N sub 2 O plasma. Sub-4-nm thick polyoxides were grown on n sup + and p sup + polysilicon layers and were characterized. These oxides had larger breakdown fields, smaller electron trapping characteristics, and larger Q sub B sub D values than those of thermal polyoxides. The electron trapping characteristics of ECR N sub 2 O plasma polyoxides, which were smaller than those of thermal polyoxides at positive bias, resulted from the smaller roughness of the polysilicon surface after the oxidation process. Under a negative constant-current stress of 20 mA/cm sup 2 for polyoxide on p sup + polysilicon were obtained. These ultrathin plasma polyoxides would be good candidates for future inter-poly dielectrics and gate oxides for thin film transistors.

  15. Plasma vapor deposited n-indium tin oxide/p-copper indium oxide heterojunctions for optoelectronic device applications

    Science.gov (United States)

    Jaya, T. P.; Pradyumnan, P. P.

    2017-12-01

    Transparent crystalline n-indium tin oxide/p-copper indium oxide diode structures were fabricated on quartz substrates by plasma vapor deposition using radio frequency (RF) magnetron sputtering. The p–n heterojunction diodes were highly transparent in the visible region and exhibited rectifying current–voltage (I–V) characteristics with a good ideality factor. The sputter power during fabrication of the p-layer was found to have a profound effect on I–V characteristics, and the diode with the p-type layer deposited at a maximum power of 200 W exhibited the highest value of the diode ideality factor (η value) of 2.162, which suggests its potential use in optoelectronic applications. The ratio of forward current to reverse current exceeded 80 within the range of applied voltages of ‑1.5 to +1.5 V in all cases. The diode structure possessed an optical transmission of 60–70% in the visible region.

  16. Developmental regulation of ecdysone receptor (EcR and EcR-controlled gene expression during pharate-adult development of honeybees (Apis mellifera.

    Directory of Open Access Journals (Sweden)

    Tathyana Rachel Palo Mello

    2014-12-01

    Full Text Available Major developmental transitions in multicellular organisms are driven by steroid hormones. In insects, these, together with juvenile hormone (JH, control development, metamorphosis, reproduction and aging, and are also suggested to play an important role in caste differentiation of social insects. Here, we aimed to determine how EcR transcription and ecdysteroid titers are related during honeybee postembryonic development and what may actually be the role of EcR in caste development of this social insect. In addition, we expected that knocking-down EcR gene expression would give us information on the participation of the respective protein in regulating downstream targets of EcR. We found that in Apis mellifera females, EcR-A is the predominantly expressed variant in postembryonic development, while EcR-B transcript levels are higher in embryos, indicating an early developmental switch in EcR function. During larval and pupal stages, EcR-B expression levels are very low, while EcR-A transcripts are more variable and abundant in workers compared to queens. Strikingly, these transcript levels are opposite to the ecdysteroid titer profile. 20-hydroxyecdysone (20E application experiments revealed that low 20E levels induce EcR expression during development, whereas high ecdysteroid titers seem to be repressive. By means of RNAi-mediated knockdown (KD of both EcR transcript variants we detected the differential expression of 234 poly-A+ transcripts encoding genes such as CYPs, MRJPs and certain hormone response genes (Kr-h1 and ftz-f1. EcR-KD also promoted the differential expression of 70 miRNAs, including highly conserved ones (e.g. miR-133 and miR-375, as well honeybee-specific ones (e.g. miR-3745 and miR-3761. Our results put in evidence a broad spectrum of EcR-controlled gene expression during postembryonic development of honeybees, revealing new facets of EcR biology in this social insect.

  17. Variation of plasma parameters in a modified mode of plasma ...

    Indian Academy of Sciences (India)

    grounded target and produce plasma there. The plasma parameters can be controlled by varying the voltages applied to the source magnetic cage and the separation grid of the device. Keywords. Plasma parameters; double plasma device; filament discharge; multidipole magnetic cage. PACS Nos 52.75.Xx; 52.25.

  18. Characterization and modeling of multi-dipolar microwave plasmas: application to multi-dipolar plasma assisted sputtering; Caracterisation et modelisation des plasmas micro-onde multi-dipolaires: application a la pulverisation assistee par plasma multi-dipolaire

    Energy Technology Data Exchange (ETDEWEB)

    Tran, T.V

    2006-12-15

    The scaling up of plasma processes in the low pressure range remains a question to be solved for their rise at the industrial level. One solution is the uniform distribution of elementary plasma sources where the plasma is produced via electron cyclotron resonance (ECR) coupling. These elementary plasma sources are made up of a cylindrical permanent magnet (magnetic dipole) set at the end of a coaxial microwave line. Although of simple concept, the optimisation of these dipolar plasma sources is in fact a complex problem. It requires the knowledge, on one hand, of the configurations of static magnetic fields and microwave electric fields, and, on the other hand, of the mechanisms of plasma production in the region of high intensity magnetic field (ECR condition), and of plasma diffusion. Therefore, the experimental characterisation of the operating ranges and plasma parameters has been performed by Langmuir probes and optical emission spectroscopy on different configurations of dipolar sources. At the same time, in a first analytical approach, calculations have been made on simple magnetic field configurations, motion and trajectory of electrons in these magnetic fields, and the acceleration of electrons by ECR coupling. Then, the results have been used for the validation of the numerical modelling of the electron trajectories by using a hybrid PIC (particle-in-cell) / MC (Monte Carlo) method. The experimental study has evidenced large operating domains, between 15 and 200 W of microwave power, and from 0.5 to 15 mtorr argon pressure. The analysis of plasma parameters has shown that the region of ECR coupling is localised near the equatorial plane of the magnet and dependent on magnet geometry. These characterizations, applied to a cylindrical reactor using 48 sources, have shown that densities between 10{sup 11} and 10{sup 12} cm{sup -3} could be achieved in the central part of the volume at a few mtorr argon pressures. The modelling of electron trajectories near

  19. ANALYSIS OF X-RAY SPECTRA EMITTED FROM THE VENUS ECR ION SOURCE

    Energy Technology Data Exchange (ETDEWEB)

    Benitez, J.; Leitner, D.

    2008-01-01

    The Versatile Electron Cyclotron resonance ion source for Nuclear Science (VENUS), located at Lawrence Berkeley National Lab’s 88-inch cyclotron, extracts ion beams from a plasma created by ionizing a gas with energetic electrons. Liquid-helium cooled superconducting coils produce magnetic fi elds that confi ne the plasma and high microwave frequencies heat the electrons enough to allow for successive ionizations of the neutral gas atoms. The combination of strong plasma confi nement and high microwave frequencies results in VENUS’ production of record breaking ion beam currents and high charge state distributions. While in operation, VENUS produces signifi cant quantities of bremsstrahlung, in the form of x-rays, primarily through two processes: 1) electron-ion collisions within the plasma, and 2) electrons are lost from the plasma, collide with the plasma chamber wall, and radiate bremsstrahlung due to their sudden deceleration. The bremsstrahlung deposited into the plasma chamber wall is absorbed by the cold mass used to maintain superconductivity in the magnets and poses an additional heat load on the cryostat. In order for VENUS to reach its maximum operating potential of 10 kW of 28 GHz microwave heating frequency, the heat load posed by the emitted bremsstrahlung must be understood. In addition, studying the bremsstrahlung under various conditions will help further our understanding of the dynamics within the plasma. A code has been written, using the Python programming language, to analyze the recorded bremsstrahlung spectra emitted from the extraction end of VENUS. The code outputs a spectral temperature, which is relatively indicative of the temperature of the hot electrons, and total integrated count number corresponding to each spectra. Bremsstrahlung spectra are analyzed and compared by varying two parameters: 1) the heating frequency, 18 GHz and 28 GHz, and 2) the ratio between the minimum magnetic fi eld and the resonant magnetic fi eld, .44 and

  20. Plasmas in compact traps: From ion sources to multidisciplinary research

    Science.gov (United States)

    Mascali, D.; Musumarra, A.; Leone, F.; Galatà, A.; Romano, F. P.; Gammino, S.

    2017-09-01

    In linear (minimum-B) magneto-static traps dense and hot plasmas are heated by electromagnetic radiation in the GHz domain via the Electron Cyclotron Resonance (ECR). The values of plasma density, temperature and confinement times ( n_eτ_i>10^{13} cm ^{-3} s; T_e>10 keV) are similar to the ones of thermonuclear plasmas. The research in this field -devoted to heating and confinement optimization- has been supported by numerical modeling and advanced diagnostics, for probing the plasma especially in a non-invasive way. ECR-based systems are nowadays able to produce extremely intense (tens or hundreds of mA) beams of light ions (p, d, He), and relevant currents of heavier elements (C, O, N) up to heavy ions like Xe, Pb, U. Such beams can be extracted from the trap by a proper electrostatic system. The above-mentioned properties make these plasmas very attractive for interdisciplinary researches also, such as i) nuclear decays rates measurements in stellar-like conditions, ii) energy conversion studies, being exceptional sources of short-wavelength electromagnetic radiation (EUV, X-rays, hard X-rays and gammas, useful in material science and archaeometry), iii) environments allowing precise spectroscopical measurements as benchmarks for magnetized astrophysical plasmas. The talk will give an overview about the state-of-the-art in the field of intense ion sources, and some new perspectives for interdisciplinary research, with a special attention to the developments based at INFN-LNS.

  1. Sex Differences in Orienting to Pictures with and without Humans: Evidence from the Cardiac Evoked Response (ECR) and the Cortical Long Latency Parietal Positivity (LPP)

    Science.gov (United States)

    Althaus, Monika; Groen, Yvonne; van der Schaft, Lutske; Minderaa, Ruud B.; Tucha, Oliver; Mulder, Lambertus J. M.; Wijers, Albertus A.

    2014-01-01

    Objective This study investigated the effect of social relevance in affective pictures on two orienting responses, i.e. the evoked cardiac response (ECR), and a long latency cortical evoked potential (LPP) and whether this effect would differ between males and females. Assuming that orienting to affective social information is fundamental to experiencing affective empathy, associations between self-report measures of empathy and the two orienting responses were investigated. Method ECRs were obtained from 34 female and 30 male students, and LPPs from 25 female and 27 male students viewing 414 pictures from the International Affective Picture System. Pictures portrayed pleasant, unpleasant and neutral scenes with and without humans. Results Both the ECR and LPP showed the largest response to pictures with humans in unpleasant situations. For both measures, the responses to pictures with humans correlated with self-report measures of empathy. While we found a greater male than female responsiveness to the pictures without humans in the ECR, a greater female than male responsiveness was observed in the LPP response to pictures with humans. Conclusion and Significance The sensitivity of these orienting responses to social relevance and their differential contribution to the prediction of individual differences underline the validity of their combined use in clinical studies investigating individuals with social disabilities. PMID:25330003

  2. Ion Behavior and Gas Mixing in electron cyclotron resonance plasmas as sources of highly charged ions (concept)

    CERN Document Server

    Melin, G; Girard, A; Hitz, D

    1999-01-01

    An ECR ion source is basically an ECR heated plasma confinement machine, with hot electrons and cold ions. The main parameters of the ion population have been analyzed, including temperature, losses, and confinement time. The "gas mixing" effect has been studied in this context. An expression is derived for determining the ion temperature from the values of all extracted ion currents. One aim is to study the ion temperature behavior in argon plasmas without and with mixing different gases into the plasma. For that purpose a series of experiments has been performed where systematically one or a few parameters where changed. One conclusion is that the ion temperature indeed is decreasing due to gas mixing. A second conclusion is that the decreasing ion temperature is not a sufficient requirement for the beneficial effect of gas mixing to the production of highest charge states of argon.

  3. Geomagnetic activity effects on plasma sheet energy conversion

    Directory of Open Access Journals (Sweden)

    M. Hamrin

    2010-10-01

    Full Text Available In this article we use three years (2001, 2002, and 2004 of Cluster plasma sheet data to investigate what happens to localized energy conversion regions (ECRs in the plasma sheet during times of high magnetospheric activity. By examining variations in the power density, E·J, where E is the electric field and J is the current density obtained by Cluster, we have studied the influence on Concentrated Load Regions (CLRs and Concentrated Generator Regions (CGRs from variations in the geomagnetic disturbance level as expressed by the Kp, the AE, and the Dst indices. We find that the ECR occurrence frequency increases during higher magnetospheric activities, and that the ECRs become stronger. This is true both for CLRs and for CGRs, and the localized energy conversion therefore concerns energy conversion in both directions between the particles and the fields in the plasma sheet. A higher geomagnetic activity hence increases the general level of energy conversion in the plasma sheet. Moreover, we have shown that CLRs live longer during magnetically disturbed times, hence converting more electromagnetic energy. The CGR lifetime, on the other hand, seems to be unaffected by the geomagnetic activity level. The evidence for increased energy conversion during geomagnetically disturbed times is most clear for Kp and for AE, but there are also some indications that energy conversion increases during large negative Dst. This is consistent with the plasma sheet magnetically mapping to the auroral zone, and therefore being more tightly coupled to auroral activities and variations in the AE and Kp indices, than to variations in the ring current region as described by the Dst index.

  4. The approach of in-situ doping ion conductor fabricated with the cathodic arc plasma for all-solid-state electrochromic devices

    Directory of Open Access Journals (Sweden)

    Min-Chuan Wang

    2018-01-01

    Full Text Available The all-solid-state electrochromic device (ECD with the one substrate structure fabricated by the reactive dc magnetron sputtering (DCMS and in-situ doping cathodic vacuum arc plasma (CVAP technology has been developed. The electrochromic (EC layer and ion conductor layer were deposited by reactive DCMS and CVAP technology, respectively. The in-situ doping ion conductor Ta2O5 deposited by the CVAP technology has provided the better material structure for ion transportation and showed about 2 times ion conductivity than the external doping process. The all-solid-state ECD with the in-situ doping CVAP ion conductor layer has demonstrated a maximum transmittance variation (ΔT of 71% at 550 nm, and a faster switching speed. The lower production cost and higher process stability could be achieved by the application of in-situ doping CVAP technology without breaking the vacuum process. Furthermore, the ion doping process with the reuse of energy during the CVAP process is not only decreasing the process steps, but also reducing the process energy consumption.

  5. Effect of annealing temperature on the structural, morphological, and mechanical properties of polycrystalline zirconium oxynitride composite films deposited by plasma focus device

    Science.gov (United States)

    Khan, Ijaz A.; Kashif, Muhammad; Farid, Amjad; Rawat, Rajdeep S.; Ahmad, Riaz

    2017-12-01

    In this article, we reveal the post deposition annealing effect on the structural, morphological, and mechanical properties of polycrystalline zirconium oxynitride (P-ZrON) composite films deposited for 40 focus shots using a plasma focus device. The development of Zr(101), ZrN(111), ZrN(200), Zr3N4(320), ZrN0.28(002), and m-ZrO2(200) diffraction peaks confirms the deposition of P-ZrON composite films. The peak intensity, crystallite size, dislocation density, compressive stress, and texture coefficient of the Zr3N4(320) plane and the microstructural features such as the shape, size and distribution of nanoparticles as well as the film compactness are influenced by the annealing temperature. Elemental analysis confirms the presence of Zr, N, and O in the deposited films. The microhardness of the P-ZrON composite film annealed at 500 °C is found to be 11.87 GPa which is 7.8 times that of virgin zirconium.

  6. Measurement of ion beam angular distribution at different helium gas pressures in a plasma focus device by large-area polycarbonate detectors

    Energy Technology Data Exchange (ETDEWEB)

    Sohrabi, M.; Habibi, M., E-mail: mortezahabibi@gmail.com; Ramezani, V. [Amirkabir University of Technology, Energy Engineering and Physics Department (Iran, Islamic Republic of)

    2017-02-15

    The paper presents an experimental study and analysis of full helium ion density angular distributions in a 4-kJ plasma focus device (PFD) at pressures of 10, 15, 25, and 30 mbar using large-area polycarbonate track detectors (PCTDs) (15-cm etchable diameter) processed by 50-Hz-HV electrochemical etching (ECE). Helium ion track distributions at different pressures, in particular, at the main axis of the PFD are presented. Maximum ion track density of ~4.4 × 10{sup 4} tracks/cm{sup 2} was obtained in the PCTD placed 6 cm from the anode. The ion distributions for all pressures applied are ring-shaped, which is possibly due to the hollow cylindrical copper anode used. The large-area PCTD processed by ECE proves, at the present state-of-theart, a superior method for direct observation and analysis of ion distributions at a glance with minimum efforts and time. Some observations of the ion density distributions at different pressures are reported and discussed.

  7. Radioactive Beams from 252CF Fission Using a Gas Catcher and an ECR Charge Breeder at ATLAS

    CERN Document Server

    Pardo, Richard C; Hecht, Adam; Moore, Eugene F; Savard, Guy

    2005-01-01

    An upgrade to the radioactive beam capability of the ATLAS facility has been proposed using 252Cf fission fragments thermalized and collected into a low-energy particle beam using a helium gas catcher. In order to reaccelerate these beams an existing ATLAS ECR ion source will be reconfigured as a charge breeder source. A 1Ci 252Cf source is expected to provide sufficient yield to deliver beams of up to ~106 far from stability ions per second on target. A facility description, the expected performance and the expected performance will be presented in this paper. This work is supported by the U.S. Department of Energy, Office of Nuclear Physics, under contract W-31-109-ENG-38.

  8. Boron ion beam production with the supernanogan ECR ion source for the CERN BIO-LEIR facility

    CERN Document Server

    Stafford-Haworth, J; Scrivens, R; Toivanen, V; Röhrich, J

    2014-01-01

    To deliver B3+ ions for medical research the compounds decaborane and m-carborane were tested using the metal ions from volatile compounds (MIVOC) method with the Supernanogan 14.5 GHz ECR ion source. Using decaborane the source delivered less than 10 A intensity of B3+ and after operation large deposits of material were found inside the source. Using m-carborane 50 A of B3+ were delivered without support gas. For m-carborane, helium and oxygen support gasses were also tested, and the effects of different source tuning parameters are discussed. The average consumption of m-carborane was 0:1 mg/Ah over all operation.

  9. Confinement in Wendelstein 7-X limiter plasmas

    Science.gov (United States)

    Hirsch, M.; Dinklage, A.; Alonso, A.; Fuchert, G.; Bozhenkov, S.; Höfel, U.; Andreeva, T.; Baldzuhn, J.; Beurskens, M.; Bosch, H.-S.; Beidler, C. D.; Biedermann, C.; Blanco, E.; Brakel, R.; Burhenn, R.; Buttenschön, B.; Cappa, A.; Czarnecka, A.; Endler, M.; Estrada, T.; Fornal, T.; Geiger, J.; Grulke, O.; Harris, J. H.; Hartmann, D.; Jakubowski, M.; Klinger, T.; Knauer, J.; Kocsis, G.; König, R.; Kornejew, P.; Krämer-Flecken, A.; Krawczyk, N.; Krychowiak, M.; Kubkowska, M.; Ksiazek, I.; Langenberg, A.; Laqua, H. P.; Lazerson, S.; Maaßberg, H.; Marushchenko, N.; Marsen, S.; Moncada, V.; Moseev, D.; Naujoks, D.; Otte, M.; Pablant, N.; Pasch, E.; Pisano, F.; Rahbarnia, K.; Schröder, T.; Stange, T.; Stephey, L.; Szepesi, T.; Pedersen, T. Sunn; Trimino Mora, H.; Thomsen, H.; Tsuchiya, H.; Turkin, Yu.; Wauters, T.; Weir, G.; Wenzel, U.; Werner, A.; Wolf, R.; Wurden, G. A.; Zhang, D.; the W7-X Team

    2017-08-01

    Observations on confinement in the first experimental campaign on the optimized Stellarator Wendelstein 7-X are summarized. In this phase W7-X was equipped with five inboard limiters only and thus the discharge length restricted to avoid local overheating. Stationary plasmas are limited to low densities  <2-3 · 1019 m-3. With the available 4.3 MW ECR Heating core T e ~ 8 keV, T i ~ 1-2 keV are achieved routinely resulting in energy confinement time τ E between 80 ms to 150 ms. For these conditions the plasmas show characteristics of core electron root confinement with peaked T e-profiles and positive E r up to about half of the minor radius. Profiles and plasma currents respond to on- and off-axis heating and co- and counter ECCD respectively.

  10. Elements of plasma technology

    CERN Document Server

    Wong, Chiow San

    2016-01-01

    This book presents some fundamental aspects of plasma technology that are important for beginners interested to start research in the area of plasma technology . These include the properties of plasma, methods of plasma generation and basic plasma diagnostic techniques. It also discusses several low cost plasma devices, including pulsed plasma sources such as plasma focus, pulsed capillary discharge, vacuum spark and exploding wire; as well as low temperature plasmas such as glow discharge and dielectric barrier discharge which the authors believe may have potential applications in industry. The treatments are experimental rather than theoretical, although some theoretical background is provided where appropriate. The principles of operation of these devices are also reviewed and discussed.

  11. Plasma sweeper. [Patents

    Science.gov (United States)

    Motley, R.W.; Glanz, J.

    1982-10-25

    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.

  12. Effect of axial magnetic field on a 2.45 GHz permanent magnet ECR ion source

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, T., E-mail: tsubasa@oshima-k.ac.jp; Wada, H.; Furuse, M. [National Institute of Technology, Oshima College, 1091-1 Komatsu, Suouoshima, Oshima, Yamaguchi 742-2193 (Japan); Asaji, T. [National Institute of Technology, Toyama College, 13 Hongo, Toyama 939-8630 (Japan)

    2016-02-15

    Herein, we conduct a fundamental study to improve the generation efficiency of a multi-charged ion source using argon. A magnetic field of our electron cyclotron resonance ion source is composed of a permanent magnet and a solenoid coil. Thereby, the axial magnetic field in the chamber can be tuned. Using the solenoid coil, we varied the magnetic field strength in the plasma chamber and measured the ion beam current extracted at the electrode. We observed an approximately three times increase in the Ar{sup 4+} ion beam current when the magnetic field on the extractor-electrode side of the chamber was weakened. From our results, we can confirm that the multi-charged ion beam current changes depending on magnetic field intensity in the plasma chamber.

  13. Optimization of ECR singly-charged ion sources for the radioactive ion beam production

    CERN Document Server

    Jardin, P; Gaubert, G; Pacquet, J Y; Drobert, T; Cornell, J; Barue, C; Canet, C; Dupuis, M; Flambard, J L; Lecesne, N; Leherissier, P; Lemagnen, F; Leroy, R

    2003-01-01

    Measurements of the transformation time of atoms into ions were carried out with two 2.45 GHz electron cyclotron resonance ion sources (ECRIS) in the case of the simple ionization of He, Ne, Ar and Kr gases. The effect of the plasma volume, of the dead volumes and of the ionization efficiency are presented. Some rules are deduced for the design of the next ECRIS dedicated to radioactive ion production with noble gases.

  14. PANDORA, a new facility for interdisciplinary in-plasma physics

    Science.gov (United States)

    Mascali, D.; Musumarra, A.; Leone, F.; Romano, F. P.; Galatà, A.; Gammino, S.; Massimi, C.

    2017-07-01

    PANDORA, Plasmas for Astrophysics, Nuclear Decays Observation and Radiation for Archaeometry, is planned as a new facility based on a state-of-the-art plasma trap confining energetic plasma for performing interdisciplinary research in the fields of Nuclear Astrophysics, Astrophysics, Plasma Physics and Applications in Material Science and Archaeometry: the plasmas become the environment for measuring, for the first time, nuclear decay rates in stellar-like condition (such as 7Be decay and beta-decay involved in s-process nucleosynthesis), especially as a function of the ionization state of the plasma ions. These studies will give important contributions for addressing several astrophysical issues in both stellar and primordial nucleosynthesis environment ( e.g., determination of solar neutrino flux and 7Li Cosmological Problem), moreover the confined energetic plasma will be a unique light source for high-performance stellar spectroscopy measurements in the visible, UV and X-ray domains, offering advancements in observational astronomy. As to magnetic fields, the experimental validation of theoretical first- and second-order Landé factors will drive the layout of next-generation polarimetric units for the high-resolution spectrograph of the future giant telescopes. In PANDORA new plasma heating methods will be explored, that will push forward the ion beam output, in terms of extracted intensity and charge states. More, advanced and optimized injection methods of ions in an ECR plasma will be experimented, with the aim to optimize its capture efficiency. This will be applied to the ECR-based Charge Breeding technique, that will improve the performances of the SPES ISOL-facility at Laboratori Nazionali di Legnaro-INFN. Finally, PANDORA will be suitable for energy conversion, making the plasma a source of high-intensity electromagnetic radiation, for applications in material science and archaeometry.

  15. PANDORA, a new facility for interdisciplinary in-plasma physics

    Energy Technology Data Exchange (ETDEWEB)

    Mascali, D.; Gammino, S. [INFN-Laboratori Nazionali del Sud, Catania (Italy); Musumarra, A. [INFN-Laboratori Nazionali del Sud, Catania (Italy); University of Catania, Department of Physics and Astronomy, Catania (Italy); Leone, F. [INFN-Laboratori Nazionali del Sud, Catania (Italy); University of Catania, Department of Physics and Astronomy, Catania (Italy); INAF-OACT, Catania (Italy); Romano, F.P. [INFN-Laboratori Nazionali del Sud, Catania (Italy); CNR-IBAM, Catania (Italy); Galata, A. [INFN-Laboratori Nazionali di Legnaro, Legnaro (Italy); Massimi, C. [University of Bologna, Department of Physics and Astronomy, Bologna (Italy); INFN-Bologna, Bologna (Italy)

    2017-07-15

    PANDORA, Plasmas for Astrophysics, Nuclear Decays Observation and Radiation for Archaeometry, is planned as a new facility based on a state-of-the-art plasma trap confining energetic plasma for performing interdisciplinary research in the fields of Nuclear Astrophysics, Astrophysics, Plasma Physics and Applications in Material Science and Archaeometry: the plasmas become the environment for measuring, for the first time, nuclear decay rates in stellar-like condition (such as {sup 7}Be decay and beta-decay involved in s-process nucleosynthesis), especially as a function of the ionization state of the plasma ions. These studies will give important contributions for addressing several astrophysical issues in both stellar and primordial nucleosynthesis environment (e.g., determination of solar neutrino flux and {sup 7}Li Cosmological Problem), moreover the confined energetic plasma will be a unique light source for high-performance stellar spectroscopy measurements in the visible, UV and X-ray domains, offering advancements in observational astronomy. As to magnetic fields, the experimental validation of theoretical first- and second-order Lande factors will drive the layout of next-generation polarimetric units for the high-resolution spectrograph of the future giant telescopes. In PANDORA new plasma heating methods will be explored, that will push forward the ion beam output, in terms of extracted intensity and charge states. More, advanced and optimized injection methods of ions in an ECR plasma will be experimented, with the aim to optimize its capture efficiency. This will be applied to the ECR-based Charge Breeding technique, that will improve the performances of the SPES ISOL-facility at Laboratori Nazionali di Legnaro-INFN. Finally, PANDORA will be suitable for energy conversion, making the plasma a source of high-intensity electromagnetic radiation, for applications in material science and archaeometry. (orig.)

  16. Difference in the performances of ECR ion sources when they are fed by klystron-based generator or travelling-wave-tube-based generator

    CERN Document Server

    Gammino, S; Celona, L

    2002-01-01

    During recent experiments, a different behaviour of the electron cyclotron resonance (ECR) ion source CAESAR was observed at INFN-LNS, when it was operated by means of a travelling-wave-tube-based generator with respect to the standard operation by means of a klystron-based generator. The current available for argon-high charge states was significantly higher in the former case. The same test was repeated with the other source available at LNS, i.e. the superconducting ECR ion source SERSE, with oxygen in place of argon, and the results were similar. A description of the experimental set-up and of the results obtained in the two cases is given in the following.

  17. Artificial miRNA-mediated silencing of ecdysone receptor (EcR) affects larval development and oogenesis in Helicoverpa armigera.

    Science.gov (United States)

    Yogindran, Sneha; Rajam, Manchikatla Venkat

    2016-10-01

    The insect pests are real threat to farmers as they affect the crop yield to a great extent. The use of chemical pesticides for insect pest control has always been a matter of concern as they pollute the environment and are also harmful for human health. Bt (Bacillus thuringensis) technology helped the farmers to get rid of the insect pests, but experienced a major drawback due to the evolution of insects gaining resistance towards these toxins. Hence, alternative strategies are high on demand to control insect pests. RNA-based gene silencing is emerging as a potential tool to tackle with this problem. In this study, we have shown the use of artificial microRNA (amiRNA) to specifically target the ecdysone receptor (EcR) gene of Helicoverpa armigera (cotton bollworm), which attacks several important crops like cotton, tomato chickpea, pigeon pea, etc and causes huge yield losses. Insect let-7a precursor miRNA (pre-miRNA) backbone was used to replace the native miRNA with that of amiRNA. The precursor backbone carrying the 21 nucleotide amiRNA sequence targeting HaEcR was cloned in bacterial L4440 vector for in vitro insect feeding experiments. Larvae fed with Escherichia coli expressing amiRNA-HaEcR showed a reduction in the expression of target gene as well as genes involved in the ecdysone signaling pathway downstream to EcR and exhibited mortality and developmental defects. Stem-loop RT-PCR revealed the presence of amiRNA in the insect larvae after feeding bacteria expressing amiRNA-HaEcR, which was otherwise absent in controls. We also found a significant drop in the reproduction potential (oogenesis) of moths which emerged from treated larvae as compared to control. These results demonstrate the successful use of an insect pre-miRNA backbone to express amiRNA for gene silencing studies in insects. The method is cost effective and can be exploited as an efficient and alternative tool for insect pest management. Copyright © 2016 Elsevier Ltd. All rights

  18. A new ICRF scenario for bulk ion heating in D-T plasmas: How to utilize intrinsic impurities in fusion devices in our favour

    CERN Document Server

    Kazakov, Y O; Van Eester, D; Bilato, R; Dumont, R; Lerche, E; Mantsinen, M; Messiaen, A

    2015-01-01

    A fusion reactor requires plasma pre-heating before the rate of deuterium-tritium fusion reactions becomes significant. In ITER, radiofrequency (RF) heating of 3He ions, additionally puffed into the plasma, is one of the main options considered for increasing bulk ion temperature during the ramp-up phase of the pulse. In this paper, we propose an alternative scenario for bulk ion heating with RF waves, which requires no extra 3He puff and profits from the presence of intrinsic Beryllium impurities in the plasma. The discussed method to heat Be impurities in D-T plasmas is shown to provide an even larger fraction of fuel ion heating.

  19. RNA Interference of the Ecdysone Receptor Genes EcR and USP in Grain Aphid (Sitobion avenae F.) Affects Its Survival and Fecundity upon Feeding on Wheat Plants.

    Science.gov (United States)

    Yan, Ting; Chen, Hongmei; Sun, Yongwei; Yu, Xiudao; Xia, Lanqin

    2016-12-14

    RNA interference (RNAi) has been widely used in functional genomics of insects and received intensive attention in the development of RNAi-based plants for insect control. Ecdysone receptor (EcR) and ultraspiracle protein (USP) play important roles in molting, metamorphosis, and reproduction of insects. EcR and USP orthologs and their function in grain aphid (Sitobion avenae F.) have not been documented yet. Here, RT-PCR, qRT-PCR, dsRNA feeding assay and aphid bioassay were employed to isolate EcR and USP orthologs in grain aphid, investigate their expression patterns, and evaluate the effect of RNAi on aphid survival and fecundity, and its persistence. The results indicated that SaEcR and SaUSP exhibited similar expression profiles at different developmental stages. Oral administration of dsRNAs of SaEcR and dsSaUSP significantly decreased the survival of aphids due to the down-regulation of these two genes, respectively. The silencing effect was persistent and transgenerational, as demonstrated by the reduced survival and fecundity due to knock-down of SaEcR and SaUSP in both the surviving aphids and their offspring, even after switching to aphid-susceptible wheat plants. Taken together, our results demonstrate that SaEcR and SaUSP are essential genes in aphid growth and development, and could be used as RNAi targets for wheat aphid control.

  20. A distal 594 bp ECR specifies Hmx1 expression in pinna and lateral facial morphogenesis and is regulated by the Hox-Pbx-Meis complex.

    Science.gov (United States)

    Rosin, Jessica M; Li, Wenjie; Cox, Liza L; Rolfe, Sara M; Latorre, Victor; Akiyama, Jennifer A; Visel, Axel; Kuramoto, Takashi; Bobola, Nicoletta; Turner, Eric E; Cox, Timothy C

    2016-07-15

    Hmx1 encodes a homeodomain transcription factor expressed in the developing lateral craniofacial mesenchyme, retina and sensory ganglia. Mutation or mis-regulation of Hmx1 underlies malformations of the eye and external ear in multiple species. Deletion or insertional duplication of an evolutionarily conserved region (ECR) downstream of Hmx1 has recently been described in rat and cow, respectively. Here, we demonstrate that the impact of Hmx1 loss is greater than previously appreciated, with a variety of lateral cranioskeletal defects, auriculofacial nerve deficits, and duplication of the caudal region of the external ear. Using a transgenic approach, we demonstrate that a 594 bp sequence encompassing the ECR recapitulates specific aspects of the endogenous Hmx1 lateral facial expression pattern. Moreover, we show that Hoxa2, Meis and Pbx proteins act cooperatively on the ECR, via a core 32 bp sequence, to regulate Hmx1 expression. These studies highlight the conserved role for Hmx1 in BA2-derived tissues and provide an entry point for improved understanding of the causes of the frequent lateral facial birth defects in humans. © 2016. Published by The Company of Biologists Ltd.

  1. Escala de Ciúme Romântico (ECR: Evidências Psicométricas de uma Versão Reduzida

    Directory of Open Access Journals (Sweden)

    Valdiney Veloso Gouveia

    Full Text Available Este artigo objetivou descrever a elaboração da versão reduzida da Escala de Ciúme Romântico (ECR, reunindo evidências de sua adequação psicométrica. Dois estudos foram realizados. No Estudo 1 participaram 301 pessoas com idade média de 29 anos (54,2% mulheres. Estes responderam a ECR e perguntas demográficas. Os resultados apoiaram a adequação psicométrica da ECR, cuja análise de componentes principais mostrou dois componentes (ameaça e não ameaça com alfas de Cronbach (α superiores a 0,70. NoEstudo 2 participaram 281 pessoas com idade média de 24 anos (51,6% mulheres, as quais responderam o mesmo questionário do estudo prévio. Os resultados da análise fatorial confirmatória endossaram a solução bifatorial, resultando em uma medida breve com 15 itens, cujos fatores também apresentaram αs acima de 0,70. Concluindo, esta parece ser uma medida que apresenta evidências de validade fatorial e consistência interna, podendo ser útil em contextos de pesquisa e clínico.

  2. Uma medida de apego: versão brasileira da Experiences in Close Relationship Scale - Reduzida (ECR-R-Brasil

    Directory of Open Access Journals (Sweden)

    Jean Carlos Natividade

    2015-12-01

    Full Text Available Resumo: Os objetivos desta pesquisa foram adaptar e buscar evidências de validade para a população brasileira da versão reduzida da Experience in Close Relationship. Após procedimentos de tradução dos 12 itens, o instrumento foi respondido por 4.879 adultos de todas as regiões do país, 66% mulheres. Análises fatoriais exploratórias e confirmatórias evidenciaram a adequação da estrutura de dois fatores, em consonância com o estudo original. Os índices de consistência interna dos fatores "ansiedade" e "evitação" mostraram-se satisfatórios. Encontraram-se resultados de diferenças sexuais e correlações com tempo de relacionamento e níveis de sociossexualidade de acordo com as hipóteses teóricas e muito semelhantes aos encontrados para a versão brasileira da medida estendida. Ainda, a escala foi capaz de diferenciar participantes que estavam em relacionamento compromissado daqueles em relacionamento sem compromisso. Considera-se que as evidências de validade e fidedignidade encontradas para a ECR-R-Brasil mostraram-se satisfatórias.

  3. El teónimo PTGYH de la inscripción filistea de Ecrón

    Directory of Open Access Journals (Sweden)

    Piquer, Andrés

    2001-12-01

    Full Text Available The Philistine Ekron inscription, discovered during the 1996 archaeological campaign at Tell Miqne (Israel, is written in a Canaanite dialect, but it mentions a feminine theonym, Ptgyh, unknown until now. Its explanation has been attempted through comparison with the Indoeuropean languages. In our opinion, it may be a name composed of two elements: PT, related to the root *POT / POS 'Lord', and GYH 'earth'. Thus, this theonym may be understood as 'the Earth Lady'.La inscripción filistea de Ecrón, que fue descubierta en las excavaciones arqueológicas de Tel Miqne (Israel del año 1996, está redactada en un dialecto cananeo, pero en ella se menciona un teónimo femenino PTGYH, hasta ahora desconocido, que se ha intentado interpretar mediante las lenguas indoeuropeas. En nuestra opinión, podría tratarse de un nombre compuesto de dos elementos: PT relacionado con la raíz *POT / POS 'señor' y GYH relacionado con el griego gaîa 'tierra', lo que nos llevaría a interpretar este teónimo como 'Señora de la tierra'.

  4. Vertical profiles and two-dimensional distributions of carbon line emissions from C2+-C5+ ions in attached and RMP-assisted detached plasmas of large helical device

    Science.gov (United States)

    Zhang, Hongming; Morita, Shigeru; Dai, Shuyu; Oishi, Tetsutarou; Goto, Motoshi; Huang, Xianli; Kawamura, Gakushi; Kobayashi, Masahiro; Liu, Yang; Murakami, Izumi; Narushima, Yoshiro

    2017-02-01

    In Large Helical Device (LHD), the detached plasma is obtained without external impurity gas feed by supplying an m/n = 1/1 resonant magnetic perturbation (RMP) field to a plasma with an outwardly shifted plasma axis position of Rax = 3.90 m where the magnetic resonance exists in the stochastic magnetic field layer outside the last closed flux surface. The plasma detachment is triggered by the appearance of an m/n = 1/1 island when the density, increased using hydrogen gas feed, exceeds a threshold density. The behavior of intrinsically existing impurities, in particular, carbon originating in the graphite divertor plates, is one of the important key issues to clarify the characteristic features of the RMP-assisted plasma detachment although the particle flux still remains on some divertor plates even in the detachment phase of the discharge. For this purpose, vertical profiles and two-dimensional (2-D) distributions of edge carbon emissions of CIII to CVI have been measured at extreme ultraviolet wavelength range, and the results are compared between attached and RMP-assisted detached plasmas. It is found that the CIII and CIV emissions located in the stochastic magnetic field layer are drastically increased near the m/n = 1/1 island O-point and in the vicinity of both inboard and outboard edge separatrix X-points during the RMP-assisted detachment, while those emissions are only enhanced in the vicinity of the outboard edge X-point in attached plasmas without RMP. The result clearly indicates a change in the magnetic field lines connecting to the divertor plates, which is caused by the growth of the m/n = 1/1 edge magnetic island. In contrast, the intensity of CVI emitted radially inside the magnetic island significantly decreases during the detachment, suggesting an enhancement of the edge impurity screening. The measured carbon distribution is analyzed with a three-dimensional edge plasma transport simulation code, EMC3-EIRENE, for the attached plasmas without

  5. Physics of photonic devices

    CERN Document Server

    Chuang, Shun Lien

    2009-01-01

    The most up-to-date book available on the physics of photonic devices This new edition of Physics of Photonic Devices incorporates significant advancements in the field of photonics that have occurred since publication of the first edition (Physics of Optoelectronic Devices). New topics covered include a brief history of the invention of semiconductor lasers, the Lorentz dipole method and metal plasmas, matrix optics, surface plasma waveguides, optical ring resonators, integrated electroabsorption modulator-lasers, and solar cells. It also introduces exciting new fields of research such as:

  6. Can a Hexapole magnet of an ECR Ion Source be too strong?

    CERN Document Server

    Drentje, A G; Kremers, H R; Meyer, D; Mulder, J; Sijbring, J

    1999-01-01

    Experience of many ECRIS designers and users during more than a decade has given a few experimental rules, or "scaling laws". Many of these have been discussed at the ECRIS workshops. After the 1993 workshop it was concluded that the properties of the magnetic trap, in particular the strength of the radial component, determine to a great deal the confinement characteristics. For that reason it was decided at the KVI to choose a very strong magnet for the new 14 GHz ECRIS4 to be used in the Atomic Physics experiments. The hexapole magnet designed by the Giessen group is a good example. The induction, measured 2.5 mm inside the pole tips (i.e. at the wall of the plasma chamber) amounts more than 1.2 T. The measured radial field component Br obeys closely the expression Br= 0.00136 r2. (with B in T, r in mm). The quality of the magnetic trap can be given by the "radial mirror ratio", which is usually defined as R = Bmax / Breson, with Breson equal 0.5 T for a 14 GHz ECRIS. For the KVI magnet this would give R= 2...

  7. Preparation of Bismuth Titanate Films by Electron Cyclotron Resonance Plasma Sputtering-Chemical Vapor Deposition

    OpenAIRE

    Masumoto, H.; Hirai, T.

    1995-01-01

    Bismuth titanate (Bi4Ti3O12 : BIT) thin films were prepared on the Pt courted MgO(100) substrate by electron cyclotron resonance plasma sputtering-chemical vapor deposition (ECR plasma sputtering-CVD). Bi2O3 was used as a sputtering target and tetra-isopropoxy-titanium [Ti(i-C3H7O)4] as a CVD source. The composition of films was controlled by changing RF power (PRF) of Bi2O3 target and Ti source temperature (TTi). The stoichiometric BIT film was prepared under the condition of PRF=500W, TTi=6...

  8. The Influence of a Mouthpiece-Based Topography Measurement Device on Electronic Cigarette User's Plasma Nicotine Concentration, Heart Rate, and Subjective Effects Under Directed and Ad Libitum Use Conditions.

    Science.gov (United States)

    Spindle, Tory R; Hiler, Marzena M; Breland, Alison B; Karaoghlanian, Nareg V; Shihadeh, Alan L; Eissenberg, Thomas

    2017-04-01

    Electronic cigarettes e-cigarettes aerosolize a liquid solution often containing nicotine. e-cigarette nicotine delivery may be influenced by user puffing behaviors ("puff topography"). E-cigarette puff topography can be recorded using mouthpiece-based computerized systems. The present study sought to examine the extent to which these systems influence e-cigarette nicotine delivery and other e-cigarette associated acute effects under ad libitum use conditions. Plasma nicotine concentration, heart rate, and subjective effects were assessed in 29 experienced e-cigarette users using their preferred e-cigarette battery and liquid (≥12mg/mL nicotine) in two sessions differing only by the presence of a mouthpiece-based device. In both sessions, participants completed a directed e-cigarette use bout (10 puffs, 30-s interpuff interval) and a 90-min ad libitum bout. Puff topography was recorded in the session with the topography mouthpiece. Plasma nicotine, heart rate, and subjective effects, aside from "Did the e-cigarette Taste Good?" were independent of topography measurement (higher mean taste ratings were observed in the no topography condition). Mean (SEM) plasma nicotine concentration following the ad libitum bout was 34.3ng/mL (4.9) in the no topography condition and 35.7ng/mL (4.3) in the topography condition. Longer puff durations, longer interpuff intervals, and larger puff volumes were observed in the ad libitum relative to the directed bout. E-cigarette use significantly increased plasma nicotine concentration and heart rate while suppressing abstinence symptoms. These effects did not differ when a topography mouthpiece was present. Future studies using ad libitum e-cigarette use bouts would facilitate understanding of e-cigarette toxicant yield. No prior study has examined whether mouthpiece-based topography recording devices influence e-cigarette associated nicotine delivery, heart rate, or subjective effects under ad libitum conditions or assessed ad

  9. Sterilization/disinfection of medical devices using plasma: the flowing afterglow of the reduced-pressure N2-O2 discharge as the inactivating medium

    Science.gov (United States)

    Moisan, Michel; Boudam, Karim; Carignan, Denis; Kéroack, Danielle; Levif, Pierre; Barbeau, Jean; Séguin, Jacynthe; Kutasi, Kinga; Elmoualij, Benaïssa; Thellin, Olivier; Zorzi, Willy

    2013-07-01

    Potential sterilization/disinfection of medical devices (MDs) is investigated using a specific plasma process developed at the Université de Montréal over the last decade. The inactivating medium of the microorganisms is the flowing afterglow of a reduced-pressure N2-O2 discharge, which provides, as the main biocidal agent, photons over a broad ultraviolet (UV) wavelength range. The flowing afterglow is considered less damaging to MDs than the discharge itself. Working at gas pressures in the 400—700 Pa range (a few torr) ensures, through species diffusion, the uniform filling of large volume chambers with the species outflowing from the discharge, possibly allowing batch processing within them. As a rule, bacterial endospores are used as bio-indicators (BI) to validate sterilization processes. Under the present operating conditions, Bacillus atrophaeus is found to be the most resistant one and is therefore utilized as BI. The current paper reviews the main experimental results concerning the operation and characterization of this sterilizer/disinfector, updating and completing some of our previously published papers. It uses modeling results as guidelines, which are particularly useful when the corresponding experimental data are not (yet) available, hopefully leading to more insight into this plasma afterglow system. The species flowing out of the N2-O2 discharge can be divided into two groups, depending on the time elapsed after they left the discharge zone as they move toward the chamber, namely the early afterglow and the late afterglow. The early flowing afterglow from a pure N2 discharge (also called pink afterglow) is known to be comprised of N2+ and N4+ ions. In the present N2-O2 mixture discharge, NO+ ions are additionally generated, with a lifetime that extends over a longer period than that of the nitrogen molecular ions. We shall suppose that the disappearance of the NO+ ions marks the end of the early afterglow regime, thereby stressing our intent

  10. Long-term exposure to electromagnetic radiation from mobile phones and Wi-Fi devices decreases plasma prolactin, progesterone, and estrogen levels but increases uterine oxidative stress in pregnant rats and their offspring.

    Science.gov (United States)

    Yüksel, Murat; Nazıroğlu, Mustafa; Özkaya, Mehmet Okan

    2016-05-01

    We investigated the effects of mobile phone (900 and 1800 MHz)- and Wi-Fi (2450 MHz)-induced electromagnetic radiation (EMR) exposure on uterine oxidative stress and plasma hormone levels in pregnant rats and their offspring. Thirty-two rats and their forty newborn offspring were divided into the following four groups according to the type of EMR exposure they were subjected to: the control, 900, 1800, and 2450 MHz groups. Each experimental group was exposed to EMR for 60 min/day during the pregnancy and growth periods. The pregnant rats were allowed to stand for four generations (total 52 weeks) before, plasma and uterine samples were obtained. During the 4th, 5th, and 6th weeks of the experiment, plasma and uterine samples were also obtained from the developing rats. Although uterine lipid peroxidation increased in the EMR groups, uterine glutathione peroxidase activity (4th and 5th weeks) and plasma prolactin levels (6th week) in developing rats decreased in these groups. In the maternal rats, the plasma prolactin, estrogen, and progesterone levels decreased in the EMR groups, while the plasma total oxidant status, and body temperatures increased. There were no changes in the levels of reduced glutathione, total antioxidants, or vitamins A, C, and E in the uterine and plasma samples of maternal rats. In conclusion, although EMR exposure decreased the prolactin, estrogen, and progesterone levels in the plasma of maternal rats and their offspring, EMR-induced oxidative stress in the uteri of maternal rats increased during the development of offspring. Mobile phone- and Wi-Fi-induced EMR may be one cause of increased oxidative uterine injury in growing rats and decreased hormone levels in maternal rats. TRPV1 cation channels are the possible molecular pathways responsible for changes in the hormone, oxidative stress, and body temperature levels in the uterus of maternal rats following a year-long exposure to electromagnetic radiation exposure from mobile phones and

  11. Influence of He and Ar injection on ammonia production in N2/D2 plasma in the medium flux GyM device

    Directory of Open Access Journals (Sweden)

    L. Laguardia

    2017-08-01

    Mass-spectrometry results showed that ND3 is formed only during the plasma phase of the experiment while LIC showed that ammonia production increases with Te and with the total neutral pressure. Optical Emission Spectroscopy confirms the presence of ND species in all the cases studied. The addition of He and Ar in the N2/D2 plasma, not modifing Te and ne, causes a reduction of ammonia formation, that is negligible in the case of Ar addition, while in the case of He reaches 80%. This suggests that He modifies the physical chemical process occurring at the wall, where the adsorbed He inhibits the reactions leading to ammonia formation at the metallic surface of the vessel. These results confirm the active role of a metallic surface in ammonia production and indicate He injection as a promising solution to limit the formation of the tritiated ammonia in the N seeded plasma of ITER.

  12. Cast Off expansion plan by rapid improvement through Optimization tool design, Tool Parameters and using Six Sigma’s ECRS Technique

    Science.gov (United States)

    Gopalakrishnan, T.; Saravanan, R.

    2017-03-01

    Powerful management concepts step-up the quality of the product, time saving in producing the product thereby increase the production rate, improves tools and techniques, work culture, work place and employee motivation and morale. In this paper discussed about the case study of optimizing the tool design, tool parameters to cast off expansion plan according ECRS technique. The proposed designs and optimal tool parameters yielded best results and meet the customer demand without expansion plan. Hence the work yielded huge savings of money (direct and indirect cost), time and improved the motivation and more of employees significantly.

  13. Continuous supersonic plasma wind tunnel

    DEFF Research Database (Denmark)

    Andersen, S.A.; Jensen, Vagn Orla; Nielsen, P.

    1968-01-01

    The B field configuration of a Q-device has been modified into a magnetic Laval nozzle. Continuous supersonic plasma flow is observed with M≈3......The B field configuration of a Q-device has been modified into a magnetic Laval nozzle. Continuous supersonic plasma flow is observed with M≈3...

  14. Real Time Plasma State Monitoring

    OpenAIRE

    Kudlacek, Ondrej

    2016-01-01

    The thesis describes several methods of plasma state monitoring for feedback control. For a tokamak device operation, one needs to gain in real time some information about the plasma state. The amount of needed information increases with the size of the device. In small machines, such as ISTTOK and Golem, the plasma current centroid position control is sufficient, as the heat fluxes are low and the plasma is in limiter regime. In larger devices, like RFX-mod, TCV or ASDEX-Upgrade with more co...

  15. Plasma filamentation and shock wave enhancement in microwave rockets by combining low-frequency microwaves with external magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Masayuki, E-mail: m.takahashi@al.t.u-tokyo.ac.jp [Department of Aeronautics and Astronautics, The University of Tokyo, Bunkyo-ku 113-8656 (Japan); Ohnishi, Naofumi [Department of Aerospace Engineering, Tohoku University, Sendai 980-8579 (Japan)

    2016-08-14

    A filamentary plasma is reproduced based on a fully kinetic model of electron and ion transports coupled with electromagnetic wave propagation. The discharge plasma transits from discrete to diffusive patterns at a 110-GHz breakdown, with decrease in the ambient pressure, because of the rapid electron diffusion that occurs during an increase in the propagation speed of the ionization front. A discrete plasma is obtained at low pressures when a low-frequency microwave is irradiated because the ionization process becomes more dominant than the electron diffusion, when the electrons are effectively heated by the low-frequency microwave. The propagation speed of the plasma increases with decrease in the incident microwave frequency because of the higher ionization frequency and faster plasma diffusion resulting from the increase in the energy-absorption rate. An external magnetic field is applied to the breakdown volume, which induces plasma filamentation at lower pressures because the electron diffusion is suppressed by the magnetic field. The thrust performance of a microwave rocket is improved by the magnetic fields corresponding to the electron cyclotron resonance (ECR) and its higher-harmonic heating, because slower propagation of the ionization front and larger energy-absorption rates are obtained at lower pressures. It would be advantageous if the fundamental mode of ECR heating is coupled with a lower frequency microwave instead of combining the higher-harmonic ECR heating with the higher frequency microwave. This can improve the thrust performance with smaller magnetic fields even if the propagation speed increases because of the decrease in the incident microwave frequency.

  16. Electrosurgical plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Stalder, Kenneth R; McMillen, Donald F; Woloszko, Jean [ArthroCare Corp., Sunnyvale, CA 94085-3523 (United States)

    2005-06-07

    Electrosurgical medical devices based on repetitively pulsed nonequilibrium micron-scale to millimetre-scale plasma discharges in saline solutions are described. The formation of vapour layers (bubbles) around active electrodes appears to be a common feature at moderate (<300 V rms) voltages, and dissociation, excitation and ionization of the vapour in these bubbles produces chemical conditions that are thought to be the source of beneficial tissue removal and treatment. Experimental data are discussed, as are the results of modelling efforts of the plasma chemistry. Hydroxyl radicals, hydrogen atoms and other species are observed spectroscopically and their interactions with collagen, a common component of tissue encountered in surgical situations, are considered. Several pathways by which hydroxyl radicals interacting with collagen can lead to tissue removal are discussed.

  17. Fusion plasmas

    Science.gov (United States)

    Engelmann, F.

    1995-09-01

    In the following, a synthetic review of the information reported at the Conference will be given. No attempt is made to summarize specific contributions; rather the material contributed will be looked at from a few different angles. All areas of fusion plasma physics were represented: there were experimental results on magnetic confinement (tokamaks; stellarators; mirrors; reversed field pinches; field reversed configurations; Z-pinches, with emphasis on the dense Z-pinch; plasma focus, ect.) and on inertial confinement; related modelling and diagnolstics development; theory, as well as some technological activities (power generators; RF sources, etc.) and component (e.g. antennae) development for smaller fusion devices. In particular, fusion-related research in Latin America was exhaustively covered. In addition, large future projects in fusion research were summarized. (AIP)

  18. Final report for the NSF/DOE partnership in basic plasma science grant DE-FG02-06ER54906 'Laser-driven collisionless shocks in the Large Plasma Device'

    Energy Technology Data Exchange (ETDEWEB)

    Niemann, Christoph [UCLA, CA (United States); Gekelman, W. [UCLA, CA (United States); Winske, D. [LANL, NM (United States); Larsen, D. [LLNL, CA (United States)

    2012-12-14

    We have performed several thousand high-energy laser shots in the LAPD to investigate the dynamics of an exploding laser-produced plasma in a large ambient magneto-plasma. Debris-ions expanding at super-Alfvenic velocity (up to MA=1.5) expel the ambient magnetic field, creating a large (> 20 cm) diamagnetic cavity. We observed field compressions of up to B/B{sub 0} = 1.5 at the edge of the bubble, consistent with the MHD jump conditions, as well as localized electron heating at the edge of the bubble. Two-dimensional hybrid simulations reproduce these measurements well and show that the majority of the ambient ions are energized by the magnetic piston to super-Alfvenic speeds and swept outside the bubble volume. Nonlinear shear-Alfven waves ({delta}B/B{sub 0} > 25%) are radiated from the cavity with a coupling efficiency of 70% from magnetic energy in the bubble to the wave. While the data is consistent with a weak magneto-sonic shock, the experiments were severely limited by the low ambient plasma densities (10{sup 12} cm{sup -3}). 2D hybrid simulations indicate that future experiments with the new LAPD plasma source and densities in excess of 10{sup 13} cm{sup -3} will drive full-blown collisionless shocks with MA>10 over several c/wpi and shocked Larmor radii. In a separate experiment at the LANL Trident laser facility we have performed a proof-of-principle experiment at higher densities to demonstrate key elements of collisionless shocks in laser-produced magnetized plasmas with important implications to NIF. Simultaneously we have upgraded the UCLA glass-laser system by adding two large amplitude disk amplifiers from the NOVA laser and boost the on-target energy from 30 J to up to 1 kJ, making this one of the world’s largest university-scale laser systems. We now have the infrastructure in place to perform novel and unique high-impact experiments on collision-less shocks at the LAPD.

  19. The 26th IEEE international conference on plasma science

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    Some of the sessions covered by this conference are: Basic Processes in Fully and Partially Ionized Plasmas; Slow Wave Devices; Laser-Produced Plasma; Non-Equilibrium Plasma Processing; Space Plasmas and Partially Ionized Gases; Microwave Plasmas; Inertial Confinement Fusion; Plasma Diagnostics; Computational Plasma Physics; Microwave Systems; Laser Produced Plasmas and Dense Plasma Focus; Intense Electron and Ion Beams; Fast Wave Devices; Spherical Configurations and Ball Lightning; Thermal Plasma Chemistry and Processing and Environmental Issues in Plasma Science; Plasma, Ion, and Electron Sources; Fast Wave Devices and Intense Beams; Fast Z-pinches and X-ray Lasers; Plasma Opening Switches; Plasma for Lighting; Intense Beams; Vacuum Microwaves; Magnetic Fusion Energy; and Plasma Thrusters and Arcs. Separate abstracts were prepared for some of the papers in this volume.

  20. Plasma processing for VLSI

    CERN Document Server

    Einspruch, Norman G

    1984-01-01

    VLSI Electronics: Microstructure Science, Volume 8: Plasma Processing for VLSI (Very Large Scale Integration) discusses the utilization of plasmas for general semiconductor processing. It also includes expositions on advanced deposition of materials for metallization, lithographic methods that use plasmas as exposure sources and for multiple resist patterning, and device structures made possible by anisotropic etching.This volume is divided into four sections. It begins with the history of plasma processing, a discussion of some of the early developments and trends for VLSI. The second section

  1. Princeton Plasma Physics Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    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.

  2. Tobacco rattle virus (TRV) based silencing of cotton enoyl-CoA reductase (ECR) gene and the role of very long chain fatty acids in normal leaf development and resistance to wilt disease

    Science.gov (United States)

    A Tobacco rattle virus (TRV) based virus-induced gene silencing (VIGS) assay was employed as a reverse genetic approach to study gene function in cotton (Gossypium hirsutum). This approach was used to investigate the function of Enoyl-CoA reductase (GhECR) in pathogen defense. Amino acid sequence al...

  3. What is a plasma?

    Energy Technology Data Exchange (ETDEWEB)

    Intrator, Thomas P. [Los Alamos National Laboratory

    2012-08-30

    This introduction will define the plasma fourth state of matter, where we find plasmas on earth and beyond, and why they are useful. There are applications to many consumer items, fusion energy, scientific devices, satellite communications, semiconductor processing, spacecraft propulsion, and more. Since 99% of our observable universe is ionized gas, plasma physics determines many important features of astrophysics, space physics, and magnetosphere physics in our solar system. We describe some plasma characteristics, examples in nature, some useful applications, how to create plasmas. A brief introduction to the theoretical framework includes the connection between kinetic and fluid descriptions, quasi neutrality, Debye shielding, ambipolar electric fields, some plasma waves. Hands-on demonstrations follow. More complete explanations will follow next week.

  4. Recent Results from the Plasma Science Education Laboratory

    Science.gov (United States)

    Post-Zwicker, Andrew

    2003-10-01

    A major new research and teaching facility, the Plasma Science Education Laboratory (PSEL), opened in the summer of 2002. Utilizing the unique resources of PPPL, the PSEL is a cutting-edge education laboratory that brings the beauty and complexity of plasmas to a greatly expanded range of populations that rarely have the chance to study plasma physics in a hands-on manner. The PSEL is more than 3,600 sq. ft. with a large general lab area, smaller rooms for advanced projects, and a classroom. Plasma physics research in the PSEL currently focuses upon three distinct areas: dusty plasmas, applications of double layers to ion transport in a biological cell membrane, and plasma processing with an ECR sputtering source. This research is performed by both undergraduate students, as well as high school students and teachers. The general lab area is primarily used to teach science education topics centered upon plasmas and non-fossil fuel energy sources, in particular fusion, solar, and hydrogen fuel cells. Here, the audience includes K-12 teachers and students, particularly those underrepresented in physics. Recent results from both the research and education activities in the PSEL will be presented during this talk.

  5. Plasma Air Decontamination System (PADS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed Plasma Air Decontamination System (PADS) is a trace contaminant control device based on non-thermal atmospheric-pressure plasma technology. Compared to...

  6. Plasma Air Decontamination System (PADS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed Plasma Air Decontamination System (PADS) is a trace contaminant control device based on non-thermal atmospheric pressure plasma technology that operates...

  7. IEEE International conference on plasma science: Conference record--Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1993-01-01

    The conference covered the following topics: basic plasma physics; vacuum electronics; gaseous and electrical gas discharges; laser-produced plasma; space plasmas; computational plasma science; plasma diagnostics; electron, ion and plasma sources; intense electron and ion beams; intense beam microwaves; fast wave M/W devices; microwave-plasma interactions; magnetic fusion; MHD; plasma focus; ultrafast z-pinches and x-ray lasers; plasma processing; fast-opening switches; EM and ETH launchers; solid-state plasmas and switches; plasmas for lighting; ball lightning and spherical plasma configurations; and environmental/energy issues. Separate abstracts were prepared for 379 items in this conference.

  8. IEEE conference record -- abstracts: 1995 IEEE international conference on plasma science

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    Topics covered at this meeting are: computational plasma physics; slow wave devices; basic phenomena in fully ionized plasmas; microwave-plasma interactions; space plasmas; fast wave devices; plasma processing; plasma, ion, and electron sources; vacuum microelectronics; basic phenomena in partially ionized gases; microwave systems; plasma diagnostics; magnetic fusion theory/experiment; fast opening switches; laser-produced plasmas; dense plasma focus; intense ion and electron beams; plasmas for lighting; fast z-pinches and x-ray lasers; intense beam microwaves; ball lightning/spherical plasma configuration; environmental plasma science; EM and ETH launchers; and environmental/energy issues in plasma science. Separate abstracts were prepared for most of the individual papers.

  9. Attachment Insecurity in Advanced Cancer Patients: Psychometric Properties of the German Version of the Brief Experiences in Close Relationships Scale (ECR-M16-G).

    Science.gov (United States)

    Philipp, Rebecca; Vehling, Sigrun; Scheffold, Katharina; Grünke, Britta; Härter, Martin; Mehnert, Anja; Oechsle, Karin; Schulz-Kindermann, Frank; Lo, Christopher

    2017-10-01

    Attachment insecurity refers to difficulty in trusting and relying on others in times of need. Its underlying factors attachment anxiety and attachment avoidance have been empirically associated with impaired coping in advanced cancer and, therefore, should be considered in individually tailored medical and psychosocial treatment. The objective of this study was to evaluate the psychometric properties of the German translation of the Brief Experiences in Close Relationships Scale (ECR-M16-G). We recruited 182 advanced cancer patients from outpatient psycho-oncology clinics of the University Medical Center Hamburg-Eppendorf and the University Medical Center Leipzig, local and external cancer care facilities. We performed confirmatory factor analysis to replicate the higher order factor structure reported in previous research. We conducted item and reliability analysis, also correlation analysis, to examine concurrent validity. One hundred fifty-eight patients completed the ECR-M16-G (women 61%, mean age 57.9, SD = 11.1). We replicated the factor structure with the subscales Attachment Anxiety and Attachment Avoidance as second-order factors and Worrying about relationships, Frustration about unavailability, Discomfort with close others, and Turning away from others as first-order factors. An adjusted model that interchanged factor loadings of items 4 and 10 showed good fit (Comparative Fit Index = 0.94, Non-Normed Fit Index = 0.93, root mean square error of approximation = 0.05). Subscales showed acceptable to good internal consistency (anxiety α = .81 and avoidance α = .78). Attachment insecurity (mean = 3.1, SD = 1.0) was positively associated with depression, anxiety, demoralization (P attachment insecurity in patients with advanced cancer and can be recommended as a tool for clinical care and further research. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  10. Measurements of Soft-X-Ray Spectra in Ecr-Heated Tokamak Plasmas and a Comparison with Fokker-Planck Simulations

    NARCIS (Netherlands)

    Da Cruz, D. F.; Peeters, A.G.; Donne, A. J. H.; Cardozo, N. J. L.; Westerhof, E.

    1993-01-01

    Soft x-ray spectra have been measured in the RTP tokamak both during the ohmic phase for densities 2 X 10(19) less-than-or-equal-to n(e)(0) less-than-or-equal-to 7 X 10(19) m-3, and during the ECRH phase at a density n(e)(0) = 2 X 10(19) m-3 for several power levels. Large deformations of the soft

  11. Insertion devices

    CERN Document Server

    Bahrdt, J

    2006-01-01

    The interaction of an insertion device with the electron beam in a storage ring is discussed. The radiation property including brightness, ux and polarization of an ideal and real planar and helical / elliptical device is described. The magnet design of planar, helical, quasiperiodic devices and of devices with a reduced on axis power density are resumed.

  12. Erosion yield and W surface enrichment of Fe-W model system exposed to low flux deuterium plasma in the linear device GyM

    Directory of Open Access Journals (Sweden)

    R. Caniello

    2017-01-01

    Full Text Available Iron-tungsten (Fe-W mixed films were exposed to the low flux deuterium plasma of GyM in order to study the behavior of the sputtering yield with the ion fluence and temperature of the samples. From literature, it is known that an increase of the former lowers the Fe-W layers’ sputtering yield as a consequence of the preferential sputtering of Fe leading to an enrichment in W of the outermost layers. An opposite trend was instead found for the latter probably due to the inter-diffusion of Fe and W (effective from 200 °C resulting in the suppression of the W enrichment. Moreover, from 500 °C, also W segregation to the surface occurs. What is missing from literature is a systematic investigation of the role of temperature on W enrichment. In this work, dedicated experiments in GyM were carried out to fill this gap. After exposure, W enrichment was evaluated by Rutherford Backscattering Spectrometry (RBS and inferred from measuring the eroded thickness of the samples using RBS and profilometer. Concerning the Fe-W sputtering yield as a function of fluence, it decreases by a factor of ∼3 between the lowest (3.0×1022D+m−2 and the highest fluence (9.0×1023D+m−2 values considered. The other main result is that, at the lowest fluence, the exposure at room temperature leads to an erosion of the Fe-W samples more pronounced than that associated to the exposure at 500 °C.

  13. Material design of plasma-enhanced chemical vapour deposition SiCH films for low-k cap layers in the further scaling of ultra-large-scale integrated devices-Cu interconnects

    Directory of Open Access Journals (Sweden)

    Hideharu Shimizu, Shuji Nagano, Akira Uedono, Nobuo Tajima, Takeshi Momose and Yukihiro Shimogaki

    2013-01-01

    Full Text Available Cap layers for Cu interconnects in ultra-large-scale integrated devices (ULSIs, with a low dielectric constant (k-value and strong barrier properties against Cu and moisture diffusion, are required for the future further scaling of ULSIs. There is a trade-off, however, between reducing the k-value and maintaining strong barrier properties. Using quantum mechanical simulations and other theoretical computations, we have designed ideal dielectrics: SiCH films with Si–C2H4–Si networks. Such films were estimated to have low porosity and low k; thus they are the key to realizing a cap layer with a low k and strong barrier properties against diffusion. For fabricating these ideal SiCH films, we designed four novel precursors: isobutyl trimethylsilane, diisobutyl dimethylsilane, 1, 1-divinylsilacyclopentane and 5-silaspiro [4,4] noname, based on quantum chemical calculations, because such fabrication is difficult by controlling only the process conditions in plasma-enhanced chemical vapor deposition (PECVD using conventional precursors. We demonstrated that SiCH films prepared using these newly designed precursors had large amounts of Si–C2H4–Si networks and strong barrier properties. The pore structure of these films was then analyzed by positron annihilation spectroscopy, revealing that these SiCH films actually had low porosity, as we designed. These results validate our material and precursor design concepts for developing a PECVD process capable of fabricating a low-k cap layer.

  14. Large Helical Device project

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-05-01

    In this book, the results of the scientific research on the design, trial manufacture and manufacturing processes of the Large Helical Device which was constructed in National Institute for Fusion Science are summarized. The LHD is the largest helical device in the world, and the largest superconducting system in the world. It possesses the following features: the optimization of heliotron magnetic field coordination, the adoption of superconducting magnets for 2 helical magnetic field coils and 6 poloidal coils, the adoption of helical diverter which enables steady plasma experiment, the flexible specification as the experimental facility and so on. The construction has been carried out smoothly, and in March, 1998, first plasma was generated. The outline of the Large Helical Device project, the physical design, the equipment design, the research and development of superconductivity and low temperature system, the design and manufacture of the superconducting and low temperature systems, the design and manufacture of the power source and superconducting bus-line, vacuum vessel and others, electron cyclotron heating, neutral beam injection and ion cyclotron RF heating, measurement system, control and data processing, safety management, the theory and analysis of LHD plasma, the visualization of the result of theoretical analysis, the analysis of the experimental data, and the experiment plan are described. (K.I.)

  15. Continuous supersonic plasma wind tunnel

    DEFF Research Database (Denmark)

    Andersen, S.A.; Jensen, Vagn Orla; Nielsen, P.

    1969-01-01

    The normal magnetic field configuration of a Q device has been modified to obtain a 'magnetic Laval nozzle'. Continuous supersonic plasma 'winds' are obtained with Mach numbers ~3. The magnetic nozzle appears well suited for the study of the interaction of supersonic plasma 'winds' with either...

  16. Occurrence and location of concentrated load and generator regions observed by Cluster in the plasma sheet

    Directory of Open Access Journals (Sweden)

    M. Hamrin

    2009-11-01

    Full Text Available Here, and in a companion paper by Hamrin et al. (2009 [Scale size and life time of energy conversion regions observed by Cluster in the plasma sheet], we investigate localized energy conversion regions (ECRs in the Earth's plasma sheet. In total we have studied 151 ECRs within 660 h of plasma sheet data from the summer and fall of 2001 when Cluster was close to apogee at an altitude of about 15–20 RE. Cluster offers appropriate conditions for the investigation of energy conversion by the evaluation of the power density, E·J, where E is the electric field and J the current density. From the sign of the power density, we have identified more than three times as many Concentrated Load Regions (CLRs as Concentrated Generator Regions (CGRs. We also note that the CLRs appear to be stronger. To our knowledge, these are the first in situ observations confirming the general notion of the plasma sheet, on the average, behaving as a load. At the same time the plasma sheet appears to be highly structured, with energy conversion occurring in both directions between the fields and the particles. From our data we also find that the CLRs appear to be located closer to the neutral sheet, while CGRs prefer locations towards the plasma sheet boundary layer (PSBL. For both CLRs and CGRs, E and J in the GSM y (cross-tail direction dominate the total power density, even though the z contribution occasionally can be significant. The prevalence of the y-direction seems to be weaker for the CGRs, possibly related to a higher fluctuation level near the PSBL.

  17. Photovoltaic device

    Science.gov (United States)

    Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.

    2015-09-01

    The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device (10) with a multilayered photovoltaic cell assembly (100) and a body portion (200) joined at an interface region (410) and including an intermediate layer (500), at least one interconnecting structural member (1500), relieving feature (2500), unique component geometry, or any combination thereof.

  18. Photovoltaic device

    Energy Technology Data Exchange (ETDEWEB)

    Reese, Jason A; Keenihan, James R; Gaston, Ryan S; Kauffmann, Keith L; Langmaid, Joseph A; Lopez, Leonardo; Maak, Kevin D; Mills, Michael E; Ramesh, Narayan; Teli, Samar R

    2017-03-21

    The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.

  19. Concentration device

    DEFF Research Database (Denmark)

    2013-01-01

    A concentration device (2) for filter filtration concentration of particles (4) from a volume of a fluid (6). The concentration device (2) comprises a filter (8) configured to filter particles (4) of a predefined size in the volume of the fluid (6). The concentration device (2) comprises...

  20. Enhancement of octacalcium phosphate deposition on a titanium surface activated by electron cyclotron resonance plasma oxidation.

    Science.gov (United States)

    Orii, Yusuke; Masumoto, Hiroshi; Honda, Yoshitomo; Anada, Takahisa; Goto, Takashi; Sasaki, Keiichi; Suzuki, Osamu

    2010-05-01

    The present study was designed to investigate whether the formation of octacalcium phosphate (OCP) is accelerated on titanium (Ti) surface by an electron cyclotron resonance (ECR) plasma oxidation at various pressures and temperatures. X-ray diffraction (XRD) of Ti-oxidized substrates showed that the rutile TiO(2) phase on its surfaces appeared at 300 degrees C and was crystallized when the oxidation temperature increased up to 600 degrees C. The thickness of TiO(2) film on the substrates increased progressively as the temperature increased. The oxidized Ti surfaces were soaked in calcium and phosphate solutions supersaturated with respect to both hydroxyapatite (HA) and OCP but slightly supersaturated with dicalcium phosphate dihydrate (DCPD). OCP crystals with a blade-like morphology were deposited as the primary crystalline phase on Ti substrates, while DCPD was included as a minor constituent. The amount of OCP deposition was maximized under 0.015 Pa in 300 degrees C. On the other hand, the oxidation temperature did not show a significant effect on the deposit in the range examined. The phase conversion from OCP to HA, determined by XRD, was demonstrated to occur even at 1 day and to advance until 7 days by immersing the Ti substrate with the deposit in simulated body fluid at 37 degrees C. The present results suggest that ECR plasma oxidation could be used to improve a Ti surface regarding its bioactivity due to the enhancement of osteoconductive OCP deposition. (c) 2010 Wiley Periodicals, Inc.

  1. Experimental studies of radiation resistance of boron nitride, C2C ceramics Al{sub 2}O{sub 3} and carbon-fiber composites using a PF-1000 plasma-focus device

    Energy Technology Data Exchange (ETDEWEB)

    Gribkov, V A; Demina, E V; Dubrovsky, A V; Pimenov, V N; Maslyaev, S V [Laboratory for Radiation Interaction with Metals, A A Baikov Institute of Metallurgy and Material Science, 119991 Moscow (Russian Federation); Tuniz, C [Multidisciplinary Laboratory, Abdus Salam International Centre for Theoretical Physics, 34014 Trieste (Italy); Gaffka, R; Gryaznevich, M [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Skladnik-Sadowska, E; Sadowski, M J [Andrzej Soltan Institute for Nuclear Studies, 05-400 Otwock-Swierk n. Warsaw (Poland); Miklaszewski, R; Paduch, M; Scholz, M, E-mail: gribkovv@yahoo.com [Dense Magnetized Plasma Division, Institute of Plasma Physics and Laser Microfusion, 01-497 Warsaw (Poland)

    2011-04-15

    This paper reports on experiments undertaken to compare the radiation resistance of two types of ceramics, boron nitride (BN) and pure alumina (Al{sub 2}O{sub 3}), which are used in a TAEA antenna coil installed in the MAST spherical tokamak. Samples of the investigated materials (bulk BN and a 20 {mu}m film of Al{sub 2}O{sub 3} on Al substrate) were exposed on the axis of the plasma-focus PF-1000 device, which can emit intense streams of hot plasma (v{approx}10{sup 7} cm s{sup -1} and N{sub pl}{approx}10{sup 18} cm{sup -3}) and fast deuteron beams (E{sub i}{approx}100 keV). The most powerful plasma-ion pulse lasted 0.2-1.0 {mu}s and its intensity decayed in about 100 {mu}s. The irradiation process was diagnosed using fast optical cameras, laser interferometry and optical spectrometry. Experiments were performed at power flux densities equal to 10{sup 9}-10{sup 10} W cm{sup -2} or 10{sup 8}-10{sup 9} W cm{sup -2} during the most powerful stage of the interaction process. The irradiated specimens were investigated by means of optical microscopy and x-ray structure analysis (XRSA). It was shown that at 10{sup 10} W cm{sup -2} pulses the Al{sub 2}O{sub 3} coating was completely evaporated, whereas a surface of the BN sample became smoother than in the virgin one. A direct comparison of both samples after the action of 10{sup 8} W cm{sup -2} pulses demonstrated a wave-like structure (more distinct on Al{sub 2}O{sub 3}). Weighing of these samples showed, however, that the evaporation of BN was about two times stronger than that of Al{sub 2}O{sub 3} in spite of the lower irradiation flux; the XRSA showed no evidence of cracking of Al{sub 2}O{sub 3} after these pulses. The insulation properties of Al{sub 2}O{sub 3} did not decline, and the Al{sub 2}O{sub 3} coating may be potentially more beneficial, provided that it is kept below its melting point. Characteristic features of damages of a material based on the carbon-fiber composite with additions of silicium carbide (Si

  2. Plasma harmonics

    CERN Document Server

    Ganeev, Rashid A

    2014-01-01

    Preface; Why plasma harmonics? A very brief introduction Early stage of plasma harmonic studies - hopes and frustrations New developments in plasma harmonics studies: first successes Improvements of plasma harmonics; Theoretical basics of plasma harmonics; Basics of HHG Harmonic generation in fullerenes using few-cycle pulsesVarious approaches for description of observed peculiarities of resonant enhancement of a single harmonic in laser plasmaTwo-colour pump resonance-induced enhancement of odd and even harmonics from a tin plasmaCalculations of single harmonic generation from Mn plasma;Low-o

  3. Controlled fusion and plasma physics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    This document presents the several speeches that took place during the 22nd European Physical Society conference on Controlled Fusion and Plasma Physics in Bournemouth, UK, between the 2nd and 7th July 1995. The talks deal with new experiments carried out on several tokamaks, particularly Tore Supra, concerning plasma confinement and fusion. Some information on specific fusion devices or tokamak devices is provided, as well as results of experiments concerning plasma instability. Separate abstracts were prepared for all the 31 papers in this volume. (TEC).

  4. Low temperature plasma enhanced chemical vapor deposition of thin films combining mechanical stiffness, electrical insulation, and homogeneity in microcavities

    Science.gov (United States)

    Peter, S.; Günther, M.; Hauschild, D.; Richter, F.

    2010-08-01

    The deposition of hydrogenated amorphous carbon (a-C:H) as well as hydrogenated amorphous silicon carbonitride (SiCN:H) films was investigated in view of a simultaneous realization of a minimum Young's modulus (>70 GPa), a high electrical insulation (≥1 MV/cm), a low permittivity and the uniform coverage of microcavities with submillimeter dimensions. For the a-C:H deposition the precursors methane (CH4) and acetylene (C2H2) were used, while SiCN:H films were deposited from mixtures of trimethylsilane [SiH(CH3)3] with nitrogen and argon. To realize the deposition of micrometer thick films with the aforementioned complex requirements at substrate temperatures ≤200 °C, several plasma enhanced chemical vapor deposition methods were investigated: the capacitively coupled rf discharge and the microwave electron cyclotron resonance (ECR) plasma, combined with two types of pulsed substrate bias. SiCN:H films deposited at about 1 Pa from ECR plasmas with pulsed high-voltage bias best met the requirements. Pulsed biasing with pulse periods of about 1 μs and amplitudes of about -2 kV was found to be most advantageous for the conformal low temperature coating of the microtrenches, thereby ensuring the required mechanical and insulating film properties.

  5. Dense Plasma Focus - From Alternative Fusion Source to Versatile High Energy Density Plasma Source for Plasma Nanotechnology

    Science.gov (United States)

    Rawat, R. S.

    2015-03-01

    The dense plasma focus (DPF), a coaxial plasma gun, utilizes pulsed high current electrical discharge to heat and compress the plasma to very high density and temperature with energy densities in the range of 1-10 × 1010 J/m3. The DPF device has always been in the company of several alternative magnetic fusion devices as it produces intense fusion neutrons. Several experiments conducted on many different DPF devices ranging over several order of storage energy have demonstrated that at higher storage energy the neutron production does not follow I4 scaling laws and deteriorate significantly raising concern about the device's capability and relevance for fusion energy. On the other hand, the high energy density pinch plasma in DPF device makes it a multiple radiation source of ions, electron, soft and hard x-rays, and neutrons, making it useful for several applications in many different fields such as lithography, radiography, imaging, activation analysis, radioisotopes production etc. Being a source of hot dense plasma, strong shockwave, intense energetic beams and radiation, etc, the DPF device, additionally, shows tremendous potential for applications in plasma nanoscience and plasma nanotechnology. In the present paper, the key features of plasma focus device are critically discussed to understand the novelties and opportunities that this device offers in processing and synthesis of nanophase materials using, both, the top-down and bottom-up approach. The results of recent key experimental investigations performed on (i) the processing and modification of bulk target substrates for phase change, surface reconstruction and nanostructurization, (ii) the nanostructurization of PLD grown magnetic thin films, and (iii) direct synthesis of nanostructured (nanowire, nanosheets and nanoflowers) materials using anode target material ablation, ablated plasma and background reactive gas based synthesis and purely gas phase synthesis of various different types of

  6. Development of a pepper-pot emittance meter for diagnostics of low-energy multiply charged heavy ion beams extracted from an ECR ion source

    Energy Technology Data Exchange (ETDEWEB)

    Nagatomo, T., E-mail: nagatomo@riken.jp; Kase, M.; Kamigaito, O.; Nakagawa, T. [Nishina Center for Accelerator Based Science, RIKEN, Wako, Saitama 351-0198 (Japan); Tzoganis, V. [Nishina Center for Accelerator Based Science, RIKEN, Wako, Saitama 351-0198 (Japan); Cockcroft Institute, Daresbury, Warrington WA4 4AD (United Kingdom); Department of Physics, University of Liverpool, Liverpool, Merseyside L69 3BX (United Kingdom)

    2016-02-15

    Several fluorescent materials were tested for use in the imaging screen of a pepper-pot emittance meter that is suitable for investigating the beam dynamics of multiply charged heavy ions extracted from an ECR ion source. SiO{sub 2} (quartz), KBr, Eu-doped CaF{sub 2}, and Tl-doped CsI crystals were first irradiated with 6.52-keV protons to determine the effects of radiation damage on their fluorescence emission properties. For such a low-energy proton beam, only the quartz was found to be a suitable fluorescent material, since the other materials suffered a decay in fluorescence intensity with irradiation time. Subsequently, quartz was irradiated with heavy {sup 12}C{sup 4+}, {sup 16}O{sup 4+}, and {sup 40}Ar{sup 11+} ions, but it was found that the fluorescence intensity decreased too rapidly to measure the emittance of these heavy-ion beams. These results suggest that a different energy loss mechanism occurs for heavier ions and for protons.

  7. The heterodimeric ecdysteroid receptor complex in the brown shrimp Crangon crangon: EcR and RXR isoform characteristics and sensitivity towards the marine pollutant tributyltin.

    Science.gov (United States)

    Verhaegen, Yves; Parmentier, Koen; Swevers, Luc; Renders, Ellen; Rougé, Pierre; De Coen, Wim; Cooreman, Kris; Smagghe, Guy

    2011-05-15

    Decapod crustaceans are characterized by multiple ecdysteroid receptor (EcR) and retinoid-X-receptor (RXR) isoforms, which likely exhibit variant dimerization and transactivation interactions. In the brown shrimp C. crangon we cloned C-terminally truncated CrcEcR and CrcRXR isoforms and isoforms exhibiting deletions within the hinge region. For the former, in silico modeling of the CrcEcR indicated that, where the conserved helices H10 and H11 of the ligand-binding domain (LBD) are missing, an alternative C-terminal α-helix repairs the ligand-binding pocket (LBP). The truncated CrcRXR isoforms lack a major part of the LBD (H4-H12), thereby compromising ligand binding and dimerization. Through an in vitro ecdysteroid responsive reporter assay, we showed that these natural receptor variations do not impair receptor functioning but probably alter the receptor dimerization preferences. By the same in vitro assay, using full-length CrcEcR and CrcRXR, the effect of tributyltin (TBT) on ecdysteroid-induced transactivation was evaluated. The transactivation by 10nM PonA was reduced with 64% by 20 nM TBT. In silico modeling confirmed that TBT fits in the full-length CrcRXR-LBD. Furthermore, semi-quantitative PCR indicated altered expression of CrcEcR and CrcRXR isoforms after in vivo acute exposure to TBT, especially in the ovaries. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Development of a pepper-pot emittance meter for diagnostics of low-energy multiply charged heavy ion beams extracted from an ECR ion source

    Science.gov (United States)

    Nagatomo, T.; Tzoganis, V.; Kase, M.; Kamigaito, O.; Nakagawa, T.

    2016-02-01

    Several fluorescent materials were tested for use in the imaging screen of a pepper-pot emittance meter that is suitable for investigating the beam dynamics of multiply charged heavy ions extracted from an ECR ion source. SiO2 (quartz), KBr, Eu-doped CaF2, and Tl-doped CsI crystals were first irradiated with 6.52-keV protons to determine the effects of radiation damage on their fluorescence emission properties. For such a low-energy proton beam, only the quartz was found to be a suitable fluorescent material, since the other materials suffered a decay in fluorescence intensity with irradiation time. Subsequently, quartz was irradiated with heavy 12C4+, 16O4+, and 40Ar11+ ions, but it was found that the fluorescence intensity decreased too rapidly to measure the emittance of these heavy-ion beams. These results suggest that a different energy loss mechanism occurs for heavier ions and for protons.

  9. A Parallel 3d Model for The Multi-Species Low Energy BeamTransport System of the RIA Prototype ECR Ion Source Venus

    Energy Technology Data Exchange (ETDEWEB)

    Qiang, J.; Leitner, D.; Todd, D.

    2005-05-16

    The driver linac of the proposed Rare Isotope Accelerator (RIA) requires a great variety of high intensity, high charge state ion beams. In order to design and to optimize the low energy beamline optics of the RIA front end,we have developed a new parallel three-dimensional model to simulate the low energy, multi-species ion beam formation and transport from the ECR ion source extraction region to the focal plane of the analyzing magnet. A multisection overlapped computational domain has been used to break the original transport system into a number of each subsystem, macro-particle tracking is used to obtain the charge density distribution in this subdomain. The three-dimensional Poisson equation is solved within the subdomain and particle tracking is repeated until the solution converges. Two new Poisson solvers based on a combination of the spectral method and the multigrid method have been developed to solve the Poisson equation in cylindrical coordinates for the beam extraction region and in the Frenet-Serret coordinates for the bending magnet region. Some test examples and initial applications will also be presented.

  10. A Parallel 3D Model for the Multi-Species Low Energy Beam Transport System of the RIA Prototype ECR Ion Source VENUS

    CERN Document Server

    Qiang, Ji; Todd, Damon

    2005-01-01

    The driver linac of the proposed Rare Isotope Accelerator (RIA) requires a great variety of high intensity, high charge state ion beams. In order to design and optimize the low energy beam line optics of the RIA front end, we have developed a new parallel three-dimensional model to simulate the low energy, multi-species beam transport from the ECR ion source extraction region to the focal plane of the analyzing magnet. A multi-section overlapped computational domain has been used to break the original transport system into a number of independent subsystems. Within each subsystem, macro-particle tracking is used to obtain the charge density distribution in this subdomain. The three-dimensional Poisson equation is solved within the subdomain and particle tracking is repeated until the solution converges. Two new Poisson solvers based on a combination of the spectral method and the multigrid method have been developed to solve the Poisson equation in cylindrical coordinates for the beam extraction region and in...

  11. Alternative approaches to plasma confinement

    Science.gov (United States)

    Roth, J. R.

    1978-01-01

    The paper discusses 20 plasma confinement schemes each representing an alternative to the tokamak fusion reactor. Attention is given to: (1) tokamak-like devices (TORMAC, Topolotron, and the Extrap concept), (2) stellarator-like devices (Torsatron and twisted-coil stellarators), (3) mirror machines (Astron and reversed-field devices, the 2XII B experiment, laser-heated solenoids, the LITE experiment, the Kaktus-Surmac concept), (4) bumpy tori (hot electron bumpy torus, toroidal minimum-B configurations), (5) electrostatically assisted confinement (electrostatically stuffed cusps and mirrors, electrostatically assisted toroidal confinement), (6) the Migma concept, and (7) wall-confined plasmas. The plasma parameters of the devices are presented and the advantages and disadvantages of each are listed.

  12. Optimization of collision/reaction gases for determination of 90Sr in atmospheric particulate matter by inductively coupled plasma tandem mass spectrometry after direct introduction of air via a gas-exchange device

    Science.gov (United States)

    Suzuki, Yoshinari; Ohara, Ryota; Matsunaga, Kirara

    2017-09-01

    Nuclear power plant accidents release radioactive strontium 90 (90Sr) into the environment. Monitoring of 90Sr, although important, is difficult and time consuming because it emits only beta radiation. We have developed a new analytical system that enables real-time analysis of 90Sr in atmospheric particulate matter with an analytical run time of only 10 min. Briefly, after passage of an air sample through an impactor, a small fraction of the sample is introduced into a gas-exchange device, where the air is replaced by Ar. Then the sample is directly introduced into an inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) system equipped with a collision/reaction cell to eliminate isobaric interferences on 90Sr from 90Zr+, 89Y1H+, and 90Y+. Experiments with various reaction gas conditions revealed that these interferences could be minimized under the following optimized conditions: 1.0 mL min- 1 O2, 10.0 mL min- 1 H2, and 1.0 mL min- 1 NH3. The estimated background equivalent concentration and estimated detection limit of the system were 9.7 × 10- 4 and 3.6 × 10- 4 ng m- 3, respectively, which are equivalent to 4.9 × 10- 6 and 1.8 × 10- 6 Bq cm- 3. Recoveries of Sr in PM2.5 measured by real-time analysis compared to those obtained by simultaneously collection on filter was 53 ± 23%, and using this recovery, the detection limit as PM2.5 was estimated to be 3.4 ± 1.5 × 10- 6 Bq cm- 3. That is, this system enabled detection of 90Sr at concentrations < 5 × 10- 6 Bq cm- 3 even considering the insufficient fusion/vaporization/ionization efficiency of Sr in PM2.5.

  13. Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

    Science.gov (United States)

    2015-12-01

    widespread inactivation zones. The respiratory tract is covered with a mucous membrane that secretes mucous to lubricate and protect the membrane.[58...response against 80 host cell nitrosative stress.4,43 The presence of bacterial bio -physical mechanisms that may provide the capabilities to resist...excited nitrogen species, singlet oxygen and helium metastable that can be applied for bio -medical applications including inactivation of bacteria

  14. Lightweight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

    Science.gov (United States)

    2013-10-01

    data were collected for the analysis of post- treatment bacterial growth means over time. D. Messenger RNA analysis by quantitative real time-PCR...Engineering Research", Texas A&M University Corpus Christi. (September 2010). 29. Texas A&M University Corpus Christi - Facebook Page - Features DOD

  15. Innovative potential of plasma technology

    Science.gov (United States)

    Budaev, V. P.

    2017-11-01

    The review summarizes recent experimental observations of materials exposed to extreme hot plasma loads in fusion devices and plasma facilities with high-temperature plasma. Plasma load on the material in such devices lead to the stochastic clustering and fractal growth of the surface on scales from tens of nanometers to hundreds of micrometers forming statistical self-similarity of the surface roughness with extremely high specific area. Statistical characteristics of hierarchical granularity and scale invariance of such materials surface qualitatively differ from the properties of the roughness of the ordinary Brownian surface which provides a potential of innovative plasma technologies for synthesis of new nanostructured materials with programmed roughness properties, for hypersonic technologies, for biotechnology and biomedical applications.

  16. Electrodeless plasma thrusters for spacecraft: A review

    Science.gov (United States)

    Bathgate, S. N.; Bilek, M. M. M.; McKenzie, D. R.

    2017-08-01

    The physics of electrodeless electric thrusters that use directed plasma to propel spacecraft without employing electrodes subject to plasma erosion is reviewed. Electrodeless plasma thrusters are potentially more durable than presently deployed thrusters that use electrodes such as gridded ion, Hall thrusters, arcjets and resistojets. Like other plasma thrusters, electrodeless thrusters have the advantage of reduced fuel mass compared to chemical thrusters that produce the same thrust. The status of electrodeless plasma thrusters that could be used in communications satellites and in spacecraft for interplanetary missions is examined. Electrodeless thrusters under development or planned for deployment include devices that use a rotating magnetic field; devices that use a rotating electric field; pulsed inductive devices that exploit the Lorentz force on an induced current loop in a plasma; devices that use radiofrequency fields to heat plasmas and have magnetic nozzles to accelerate the hot plasma and other devices that exploit the Lorentz force. Using metrics of specific impulse and thrust efficiency, we find that the most promising designs are those that use Lorentz forces directly to expel plasma and those that use magnetic nozzles to accelerate plasma.

  17. IEEE conference record -- Abstracts: 1996 IEEE international conference on plasma science

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This meeting covered the following topics: space plasmas; non-equilibrium plasma processing; computer simulation of vacuum power tubes; vacuum microelectronics; microwave systems; basic phenomena in partially ionized gases -- gaseous electronics, electrical discharges; ball lightning/spherical plasma configuration; plasma diagnostics; plasmas for lighting; dense plasma focus; intense ion and electron beams; plasma, ion, and electron sources; flat panel displays; fast z-pinches and x-ray lasers; environmental/energy issues in plasma science; thermal plasma processing; computational plasma physics; magnetic confinement fusion; microwave-plasma interactions; space plasma engineering; EM and ETH launchers; fast wave devices; intense beam microwaves; slow wave devices; space plasma measurements; basic phenomena in fully ionized plasma -- waves, instabilities, plasma theory, etc; plasma closing switches; fast opening switches; and laser-produced plasma. Separate abstracts were prepared for most papers in this conference.

  18. Plasma astrophysics

    CERN Document Server

    Kaplan, S A; ter Haar, D

    2013-01-01

    Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

  19. Plasma waves

    CERN Document Server

    Swanson, DG

    1989-01-01

    Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th

  20. Spatial distribution of atomic and ion hydrogen flux and its effect on hydrogen recycling in long duration confined and non-confined plasmas

    Directory of Open Access Journals (Sweden)

    A. Kuzmin

    2017-08-01

    Full Text Available In order to understand the atomic hydrogen distribution in different kinds of plasma and its influence on the recycling, two kinds of plasmas were used: non-confined annular electron cyclotron resonance (ECR and confined long duration plasmas. The permeation probes are used to measure directly the atomic hydrogen flux at several poloidal positions. The permeation through metals due to the ion and atom component of the hydrogen flux to the wall is indistinguishable. To estimate the contribution of the ions directly, Langmuir probes were used. The Гinc profile behind the plasma facing components (PFCs is almost constant, ∼2 ×1018 H/s/m2.

  1. Transport of dust particles in tokamak devices

    Energy Technology Data Exchange (ETDEWEB)

    Pigarov, A.Yu. [University of California at San Diego, La Jolla, CA (United States)]. E-mail: apigarov@uscd.edu; Smirnov, R.D. [University of California at San Diego, La Jolla, CA (United States); Krasheninnikov, S.I. [University of California at San Diego, La Jolla, CA (United States); Rognlien, T.D. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Rosenberg, M. [University of California at San Diego, La Jolla, CA (United States); Soboleva, T.K. [UNAM, Mexico, DistritoFederal (Mexico)

    2007-06-15

    Recent advances in the dust transport modeling in tokamak devices are discussed. Topics include: (1) physical model for dust transport; (2) modeling results on dynamics of dust particles in plasma; (3) conditions necessary for particle growth in plasma; (4) dust spreading over the tokamak; (5) density profiles for dust particles and impurity atoms associated with dust ablation in tokamak plasma; and (6) roles of dust in material/tritium migration.

  2. Significant fluctuations in ecdysteroid receptor gene (EcR) expression in relation to seasons of molt and reproduction in the grapsid crab, Metopograpsus messor (Brachyura: Decapoda).

    Science.gov (United States)

    Shyamal, Sharmishtha; Anilkumar, G; Bhaskaran, R; Doss, G P; Durica, D S

    2015-01-15

    Metopograpsus messor, a brachyuran crab inhabiting the estuaries of North Kerala (India), is a prolific breeder releasing approximately 14-16 broods a year. The present paper reports the sequence information on the DNA binding domain (C domain, DBD), linker (D domain) and ligand binding domain (E domain, LBD) of M. messor ecdysteroid receptor (MmEcR) gene, the first grapsid brachyuran crab EcR examined. We have also measured MmEcR transcript levels in the ovary and the hepatopancreas throughout the annual cycle, with special reference to seasons of molt and reproduction. MmEcR expression in both the tissues is found to be at its peak (P<0.05) in late premolt crabs (January/May, molt/reproduction season); the expression levels are lowest (P<0.05) during June/July, when the females would neither molt nor reproduce (season for molt/reproduction repose). Intermediate levels of expression were found during the breeding season (August/December). Interestingly, this pattern of gene expression is in concordance with the fluctuating ecdysteroid levels of the hemolymph and Y organ secretory activity. The significant levels of fluctuation in the ovarian expression of MmEcR strongly suggest the ovary as a potential target for ecdysteroid action. A season-wise comparison of the gene expression reveals that ovarian MmEcR transcript levels are higher in breeding crabs (August/December) than the non-breeding animals (June/July), implicating a possible ecdysteroid role in reproduction in M. messor. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Ferroelectric devices

    CERN Document Server

    Uchino, Kenji

    2009-01-01

    Updating its bestselling predecessor, Ferroelectric Devices, Second Edition assesses the last decade of developments-and setbacks-in the commercialization of ferroelectricity. Field pioneer and esteemed author Uchino provides insight into why this relatively nascent and interdisciplinary process has failed so far without a systematic accumulation of fundamental knowledge regarding materials and device development.Filling the informational void, this collection of information reviews state-of-the-art research and development trends reflecting nano and optical technologies, environmental regulat

  4. Catalytic devices

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ming; Zhang, Xiang

    2018-01-23

    This disclosure provides systems, methods, and apparatus related to catalytic devices. In one aspect, a device includes a substrate, an electrically insulating layer disposed on the substrate, a layer of material disposed on the electrically insulating layer, and a catalyst disposed on the layer of material. The substrate comprises an electrically conductive material. The substrate and the layer of material are electrically coupled to one another and configured to have a voltage applied across them.

  5. Energy storage device with large charge separation

    Science.gov (United States)

    Holme, Timothy P.; Prinz, Friedrich B.; Iancu, Andrei

    2016-04-12

    High density energy storage in semiconductor devices is provided. There are two main aspects of the present approach. The first aspect is to provide high density energy storage in semiconductor devices based on formation of a plasma in the semiconductor. The second aspect is to provide high density energy storage based on charge separation in a p-n junction.

  6. Dense Plasma Focus Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hui [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Li, Shengtai [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jungman, Gerard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hayes-Sterbenz, Anna Catherine [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-31

    The mechanisms for pinch formation in Dense Plasma Focus (DPF) devices, with the generation of high-energy ions beams and subsequent neutron production over a relatively short distance, are not fully understood. Here we report on high-fidelity 2D and 3D numerical magnetohydrodynamic (MHD) simulations using the LA-COMPASS code to study the pinch formation dynamics and its associated instabilities and neutron production.

  7. Princeton Plasma Physics Laboratory:

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, C.A. (ed.)

    1986-01-01

    This paper discusses progress on experiments at the Princeton Plasma Physics Laboratory. The projects and areas discussed are: Principal Parameters Achieved in Experimental Devices, Tokamak Fusion Test Reactor, Princeton Large Torus, Princeton Beta Experiment, S-1 Spheromak, Current-Drive Experiment, X-ray Laser Studies, Theoretical Division, Tokamak Modeling, Spacecraft Glow Experiment, Compact Ignition Tokamak, Engineering Department, Project Planning and Safety Office, Quality Assurance and Reliability, and Administrative Operations.

  8. Plasma Simulation Program

    Energy Technology Data Exchange (ETDEWEB)

    Greenwald, Martin

    2011-10-04

    Many others in the fusion energy and advanced scientific computing communities participated in the development of this plan. The core planning team is grateful for their important contributions. This summary is meant as a quick overview the Fusion Simulation Program's (FSP's) purpose and intentions. There are several additional documents referenced within this one and all are supplemental or flow down from this Program Plan. The overall science goal of the DOE Office of Fusion Energy Sciences (FES) Fusion Simulation Program (FSP) is to develop predictive simulation capability for magnetically confined fusion plasmas at an unprecedented level of integration and fidelity. This will directly support and enable effective U.S. participation in International Thermonuclear Experimental Reactor (ITER) research and the overall mission of delivering practical fusion energy. The FSP will address a rich set of scientific issues together with experimental programs, producing validated integrated physics results. This is very well aligned with the mission of the ITER Organization to coordinate with its members the integrated modeling and control of fusion plasmas, including benchmarking and validation activities. [1]. Initial FSP research will focus on two critical Integrated Science Application (ISA) areas: ISA1, the plasma edge; and ISA2, whole device modeling (WDM) including disruption avoidance. The first of these problems involves the narrow plasma boundary layer and its complex interactions with the plasma core and the surrounding material wall. The second requires development of a computationally tractable, but comprehensive model that describes all equilibrium and dynamic processes at a sufficient level of detail to provide useful prediction of the temporal evolution of fusion plasma experiments. The initial driver for the whole device model will be prediction and avoidance of discharge-terminating disruptions, especially at high performance, which are a

  9. Conditional Eddies in Plasma Turbulence

    DEFF Research Database (Denmark)

    Johnsen, H.; Pécseli, H.L.; Trulsen, J.

    1987-01-01

    Low‐frequency electrostatic turbulence generated by the ion–ion beam instability was investigated experimentally in a double‐plasma device. Real time signals were recorded and examined by a conditional statistical analysis. Conditionally averaged potential distributions reveal the formation...... and propagation of structures with a relatively long lifetime. Various methods for making a conditional analysis are discussed and compared. The results are discussed with reference to ion phase space vortices and clump formation in collisionless plasmas....

  10. Identification device

    Science.gov (United States)

    Lin, Jian-Shian; Su, Chih-Chieh; Chou, Ta-Hsin; Wu, Mount-Learn; Lai, Chieh-Lung; Hsu, Che-Lung; Lan, Hsiao-Chin; Huang, Hung-I.; Liu, Yung-Chih; Tu, Zong-Ru; Lee, Chien-Chieh; Chang, Jenq-Yang

    2007-09-01

    In this Letter, the identification device disclosed in the present invention is comprised of: a carrier and a plurality of pseudo-pixels; wherein each of the plural pseudo-pixels is formed on the carrier and is further comprised of at least a light grating composed of a plurality of light grids. In a preferred aspect, each of the plural light grids is formed on the carrier while spacing from each other by an interval ranged between 50nm and 900nm. As the aforesaid identification device can present specific colors and patterns while it is being viewed by naked eye with respect to a specific viewing angle, the identification device is preferred for security and anti-counterfeit applications since the specific colors and patterns will become invisible when it is viewed while deviating from the specific viewing angle.

  11. ICRF heating on helical devices

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, D.A.; Lyon, J.F.; Hoffman, D.J.; Murakami, M.; England, A.C.; Wilgen, J.B.; Jaeger, E.F.; Wang, C.; Batchelor, D.B.

    1995-09-01

    Ion cyclotron range of frequency (ICRF) heating is currently in use on CHS and W7-AS and is a major element of the heating planned for steady state helical devices. In helical devices, the lack of a toroidal current eliminates both disruptions and the need for ICRF current drive, simplifying the design of antenna structures as compared to tokamak applications. However the survivability of plasma facing components and steady state cooling issues are directly applicable to tokamak devices. Results from LHD steady state experiments should be available on a time scale to strongly influence the next generation of steady state tokamak experiments. The helical plasma geometry provides challenges not faced with tokamak ICRF heating, including the potential for enhanced fast ion losses, impurity accumulation, limited access for antenna structures, and open magnetic field lines in the plasma edge. The present results and near term plans provide the basis for steady state ICRF heating of larger helical devices. An approach which includes direct electron, mode conversion, ion minority and ion Bernstein wave heating addresses these issues.

  12. ICRF heating on helical devices

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, D.A.; Lyon, J.F.; Hoffman, D.J. [and others

    1995-09-01

    Ion cyclotron range of frequency (ICRF) heating is currently in use on CHS and W7AS and is a major element of the heating planned for steady state helical devices. In helical devices, the lack of a toroidal current eliminates both disruptions and the need for ICRF current drive, simplifying the design of antenna structures as compared to tokamak applications. However the survivability of plasma facing components and steady state cooling issues are directly applicable to tokamak devices. Results from LHD steady state experiments should be available on a time scale to strongly influence the next generation of steady state tokamak experiments. The helical plasma geometry provides challenges not faced with tokamak ICRF heating, including the potential for enhanced fast ion losses, impurity accumulation, limited access for antenna structures, and open magnetic field lines in the plasma edge. The present results and near term plans provide the basis for steady state ICRF heating of larger helical devices. An approach which includes direct electron, mode conversion, ion minority and ion Bernstein wave heating addresses these issues.

  13. EDITORIAL: Plasma jets and plasma bullets Plasma jets and plasma bullets

    Science.gov (United States)

    Kong, M. G.; Ganguly, B. N.; Hicks, R. F.

    2012-06-01

    technological solution in the early to late 1990s of confining atmospheric plasmas in a small volume of plasma generation (i.e. with a small volume-to-surface ratio) and then extending it towards a downstream sample [7]-[9]. These are among the first low-temperature atmospheric plasmas aimed particularly at the exploitation of their ability to invoke the active and rich reactive chemistry close to ambient temperature. The main applications of these early devices are precision surface modification of low-temperature dielectric materials, for example thin film deposition and etching [7]-[9]. Variations of the early plasma jets include atmospheric plasma sheet jets [10] for the treatment of largely planar objects (e.g. polymeric sheets) as well as large arrays of many plasma jets for the treatment of complex-structured objects (e.g. surgical tools and open human wounds) [11]. As a material processing technology, the sub-100oC atmospheric-pressure plasma jet has benefited over the years from many innovations. Whilst a detailed account and analysis of these is clearly outside the scope of this Editorial, it is worth stating that there are different avenues with which to maintain a moderate electron density at the plasma core so as to keep the gas temperature at the sample point below a ceiling level. Most of the early studies employed excitation at radio frequencies above 10 MHz, at which electrons are largely confined in the plasma generation region, and this limits the current flow to and gas heating in the plume region of the plasma jet. Other techniques of current limitation have since been shown to be effective, including the use of dielectric barriers across a very large frequency range of 1 kHz--50 MHz, sub-microsecond pulses sustained at kHz frequencies, pulse-modulated radio frequencies and dual-frequency excitation [12]-[15]. These and other techniques have considerably advanced the atmospheric-pressure plasma jet technology. The period of some 15 years since the above

  14. Detection device

    Science.gov (United States)

    Smith, J.E.

    1981-02-27

    The present invention is directed to a detection device comprising: (1) an entrance chamber; (2) a central chamber; and (3) an exit chamber. The central chamber includes an ionizing gas, anode, and means for connecting the anode with an external power supply and pulse counter.

  15. Medical Devices

    NARCIS (Netherlands)

    Verkerke, Gijsbertus Jacob; Mahieu, H.F.; Geertsema, A.A.; Hermann, I.F.; van Horn, J.R.; Hummel, J. Marjan; van Loon, J.P.; Mihaylov, D.; van der Plaats, A.; Schraffordt Koops, H.; Schutte, H.K.; Veth, R.P.H.; de Vries, M.P.; Rakhorst, G.; Shi, Donglu

    2004-01-01

    The development of new medical devices is a very time-consuming and costly process. Besides the time between the initial idea and the time that manufacturing and testing of prototypes takes place, the time needed for the development of production facilities, production of test series, marketing,

  16. Printing Device

    NARCIS (Netherlands)

    Berg, van den M.J.; Markies, P.R.; Zuilhof, H.

    2014-01-01

    An ink jetprinting device includes a pressure chamber formed by a plurality of wall segments, a first aperture extending through a wall segment and communicating with an ink jet orifice and a second aperture extending through a wall segment and communicating with an ink supply duct. The pressure

  17. Conditioning of TJ-II Stellarator during the ECRH Plasmas Period; Acondicionamiento del Stellarator TJ-II durante la Etapa de Plasmas ECRH

    Energy Technology Data Exchange (ETDEWEB)

    Tafalla, D.; Tabares, F.L.

    2001-07-01

    The TJ-II stellarator has been conditioned by glow discharge (GD) during the first campaigns of operation, working only with ECR heating and all metal walls. The application of a He GD during the overnight period before the operation has been required in order to obtain reproducible discharges. However, the density control of the ECRH discharges was not possible because of the He implanted on the wall during GS. An short Ar GD({<=}30 min) applied before the operation allows desorbes part of the implanted He. By applying this procedure (HeGD+ArGD), reproducible and density controlled plasmas have been achieved in H{sub 2} and He. (Author) 20 refs.

  18. Characteristics of plasma properties in double discharge ablative pulsed plasma thrusters

    Science.gov (United States)

    Wu, Zhiwen; Sun, Guorui; Liu, Zhen; Liu, Xiangyang; Xie, Kan; Wang, Ningfei

    2017-11-01

    Ablative pulsed plasma thrusters, the earliest electric space propulsion devices, create highly transient plasmas in short discharges that are expelled to create thrust. In recent years, the double-discharge ablative pulsed plasma thruster design has been proposed to improve the low-thrust efficiency. In this study, optical emission spectroscopy was applied to investigate the plasma properties in different regions and energy distributions. The electron temperature and electron density of the plasmas are derived and discussed. This study provides a physical mechanism for double-discharge pulsed plasma thrusters.

  19. The diverse applications of plasma

    Science.gov (United States)

    Sharma, Mukul; Dubey, Shivani; Darwhekar, Gajanan; Jain, Sudhir Kumar

    2015-07-01

    Plasma being the fourth state of matter has always been an attraction for Physicists and Chemists. With the advent of time, plasma energy has been recognized in having widening horizons in the field of Biomedical Sciences. Plasma medicine can be subdivided into three main fields; Non-thermal atmospheric-pressure direct plasma for medical therapy; Plasma-assisted modification of bio-relevant surfaces and Plasma-based bio-decontamination and sterilization. The basis of the research is that as it has free carrier molecules, it has the ability to target specific cells and regulate functions like wound healing. Plasma does not harm healthy human cells but can kill bacteria and possibly even cancer cells to help treat various diseases. Nosocomial infection control, prevention and containment of contagious diseases, disinfection of medical devices, surface treatment (heat and UV sensitive surfaces) are research of interest. Recent success in generating plasma at very low temperature ie. Cold plasma makes the therapy painless. It has the ability to activate cellular responses and important mechanisms in the body. They target specific molecules such as prothrombin for blood coagulation, cytokines for killing bacteria, and angiogenesis for tissue regeneration. Plasma has bactericidal, fungicidal and virucidal properties. Plasma technology has flourishing future in diverse fields like Textiles, Nanofabrication, Automotives, Waste management, Microbiology, Food Hygiene, Medical Science like Skin treatments, sterilisation of wounds, Hand disinfection, Dental treatments etc. Food hygiene using plasma can be achieved in disinfection of food containers, food surface disinfection, hygiene in food handling, preparation and packaging. Therefore Plasma is most promising field for budding Scientist for fluorishing research in Biological Sciences.

  20. The diverse applications of plasma

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Mukul, E-mail: mukulsharma@acropolis.edu.in; Darwhekar, Gajanan, E-mail: gdarwhekar@acropolis.edu.in [Acropolis Institute of Pharmaceutical Education & Research, Indore MP India (India); Dubey, Shivani, E-mail: dubeyshivani08@rediffmail.com [Mata Gujri College of Professional Studies, Indore MP India (India); Jain, Sudhir Kumar, E-mail: sudhirkjain1@rediffmail.com [School of Studies in Microbiology, Vikram University, Ujjain MP India (India)

    2015-07-31

    Plasma being the fourth state of matter has always been an attraction for Physicists and Chemists. With the advent of time, plasma energy has been recognized in having widening horizons in the field of Biomedical Sciences. Plasma medicine can be subdivided into three main fields; Non-thermal atmospheric-pressure direct plasma for medical therapy; Plasma-assisted modification of bio-relevant surfaces and Plasma-based bio-decontamination and sterilization. The basis of the research is that as it has free carrier molecules, it has the ability to target specific cells and regulate functions like wound healing. Plasma does not harm healthy human cells but can kill bacteria and possibly even cancer cells to help treat various diseases. Nosocomial infection control, prevention and containment of contagious diseases, disinfection of medical devices, surface treatment (heat and UV sensitive surfaces) are research of interest. Recent success in generating plasma at very low temperature ie. Cold plasma makes the therapy painless. It has the ability to activate cellular responses and important mechanisms in the body. They target specific molecules such as prothrombin for blood coagulation, cytokines for killing bacteria, and angiogenesis for tissue regeneration. Plasma has bactericidal, fungicidal and virucidal properties. Plasma technology has flourishing future in diverse fields like Textiles, Nanofabrication, Automotives, Waste management, Microbiology, Food Hygiene, Medical Science like Skin treatments, sterilisation of wounds, Hand disinfection, Dental treatments etc. Food hygiene using plasma can be achieved in disinfection of food containers, food surface disinfection, hygiene in food handling, preparation and packaging. Therefore Plasma is most promising field for budding Scientist for fluorishing research in Biological Sciences.

  1. A novel cupping-assisted plasma treatment for skin disinfection

    Science.gov (United States)

    Xiong, Zilan; Graves, David B.

    2017-02-01

    A novel plasma treatment method/plasma source called cupping-assisted plasma treatment/source for skin disinfection is introduced. The idea combines ancient Chinese ‘cupping’ technology with plasma sources to generate active plasma inside an isolated, pressure-controlled chamber attached to the skin. Advantages of lower pressure include reducing the threshold voltage for plasma ignition and improving the spatial uniformity of the plasma treatment. In addition, with reduced pressure inside the cup, skin pore permeability might be increased and it improves attachment of the plasma device to the skin. Moreover, at a given pressure, plasma-generated active species are restricted inside the cup, raising local reactive species concentration and enhancing the measured surface disinfection rate. A surface micro-discharge (SMD) device is used as an example of a working plasma source. We report discharge characteristics and disinfection efficiency as a function of pressure and applied voltage.

  2. Plasma-based EUV light source

    Science.gov (United States)

    Shumlak, Uri; Golingo, Raymond; Nelson, Brian A.

    2010-11-02

    Various mechanisms are provided relating to plasma-based light source that may be used for lithography as well as other applications. For example, a device is disclosed for producing extreme ultraviolet (EUV) light based on a sheared plasma flow. The device can produce a plasma pinch that can last several orders of magnitude longer than what is typically sustained in a Z-pinch, thus enabling the device to provide more power output than what has been hitherto predicted in theory or attained in practice. Such power output may be used in a lithography system for manufacturing integrated circuits, enabling the use of EUV wavelengths on the order of about 13.5 nm. Lastly, the process of manufacturing such a plasma pinch is discussed, where the process includes providing a sheared flow of plasma in order to stabilize it for long periods of time.

  3. Plasma diagnostics surface analysis and interactions

    CERN Document Server

    Auciello, Orlando

    2013-01-01

    Plasmas and their interaction with materials have become subjects of major interest because of their importance in modern forefront technologies such as microelectronics, fusion energy, and space. Plasmas are used in microelectronics to process semiconductors (etching of patterns for microcircuits, plasma-induced deposition of thin films, etc.); plasmas produce deleterious erosion effects on surfaces of materials used for fusion devices and spaceships exposed to the low earth environment.Diagnostics of plasmas and materials exposed to them are fundamental to the understanding of the physical a

  4. Plasma physics

    CERN Document Server

    Drummond, James E

    2013-01-01

    A historic snapshot of the field of plasma physics, this fifty-year-old volume offers an edited collection of papers by pioneering experts in the field. In addition to assisting students in their understanding of the foundations of classical plasma physics, it provides a source of historic context for modern physicists. Highly successful upon its initial publication, this book was the standard text on plasma physics throughout the 1960s and 70s.Hailed by Science magazine as a ""well executed venture,"" the three-part treatment ranges from basic plasma theory to magnetohydrodynamics and microwa

  5. Laser device

    Science.gov (United States)

    Scott, Jill R.; Tremblay, Paul L.

    2008-08-19

    A laser device includes a virtual source configured to aim laser energy that originates from a true source. The virtual source has a vertical rotational axis during vertical motion of the virtual source and the vertical axis passes through an exit point from which the laser energy emanates independent of virtual source position. The emanating laser energy is collinear with an orientation line. The laser device includes a virtual source manipulation mechanism that positions the virtual source. The manipulation mechanism has a center of lateral pivot approximately coincident with a lateral index and a center of vertical pivot approximately coincident with a vertical index. The vertical index and lateral index intersect at an index origin. The virtual source and manipulation mechanism auto align the orientation line through the index origin during virtual source motion.

  6. "Distinvar" device

    CERN Multimedia

    CERN PhotoLab

    1965-01-01

    The alignment of one of the accelerator magnets being checked by the AR Division survey group. A "distinvar" device, invented by the group, using calibrated invar wires stretched between the fixed survey pillar (on the left) and a fixed point on the magnet. In two days it is thus possible to measure the alignment of the 100 magnets with an accuracy better than 1/10.

  7. Theoretical aspects of Dust in fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Pigarov, A.Yu.; Smirnov, R.D. [University of California at San Diego, La Jolla, CA (United States); Soboleva, T.K. [ICN, Universidad Nacional Autonoma de Mexico, Mexico D. F. (Mexico); Krasheninnikov, S.I.

    2010-05-15

    It is known that micro-particles (dust) exist in fusion devices. However, an impact of dust on plasma contamination, material migration, and performance of fusion devices is still under debate. In burning plasma experiments like ITER dust can also pose safety problems related to it's chemical activity, toxicity, tritium retention, and radioactive content. In order to address all these issues we need to understand the physics of dust generation, dynamics, and transport. In this paper, the results of recent theoretical studies of dust in fusion plasmas are reviewed. Different aspects of the physics of dust in fusion plasmas, including the processes of dust generation, charging, heating, destruction, spinning, forces acting on dust, dust collision with material walls, etc are discussed. The numerical models of these processes have been incorporated into the dust transport code DUSTT, which is capable of tracking of dust particles in fusion devices in 3D geometry. The results of the simulations of dust particle dynamics, transport, and the impact on edge plasma performance are considered. The latest results on nonlinear interactions of dust grain with tokamak plasma as well as remaining gaps in the understanding of physics of dust in fusion devices are discussed (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. Cold plasma processing to improve food safety

    Science.gov (United States)

    Cold plasma is an antimicrobial process being developed for application as a food processing technology. This novel intervention is the subject of an expanding research effort by groups around the world. A variety of devices can be used to generate cold plasma and apply it to the food commodity bein...

  9. Hydrodynamic blood plasma separation in microfluidic channels

    DEFF Research Database (Denmark)

    Jouvet, Lionel

    2010-01-01

    The separation of red blood cells from plasma flowing in microchannels is possible by biophysical effects such as the Zweifach–Fung bifurcation law. In the present study, daughter channels are placed alongside a main channel such that cells and plasma are collected separately. The device is aimed...

  10. Dynacore Final Report , Plasma Physics prototype

    NARCIS (Netherlands)

    Lourens, W.

    2000-01-01

    The generation and behaviour of plasma in a fusion device and its interaction with sur-rounding materials is studied by observing several phenomena that will accompany a plasma discharge. These phenomena are recorded by means of so called Diagnostics. These are instruments that comprise complex

  11. Plasma spectroscopy

    CERN Document Server

    Fujimoto, Takashi

    2004-01-01

    Plasma is ubiquitous, whether it occurs in cooking gas flames, fluorescent lamps or in the sun and the stars. This book deals with the light that these plasmas emit, the characteristics of the light, and why it occurs. The author provides a framework from which a coherent account of this phenomena can be made.

  12. The effect of cavity tuning on oxygen beam currents of an A-ECR type 14 GHz electron cyclotron resonance ion source

    Energy Technology Data Exchange (ETDEWEB)

    Tarvainen, O., E-mail: olli.tarvainen@jyu.fi; Orpana, J.; Kronholm, R.; Kalvas, T.; Laulainen, J.; Koivisto, H. [Department of Physics (JYFL), University of Jyväskylä, 40500 Jyväskylä (Finland); Izotov, I.; Skalyga, V. [Institute of Applied Physics, RAS, 46 Ul’yanova St., 603950 Nizhny Novgorod (Russian Federation); Lobachevsky State University of Nizhny Novgorod (UNN), 23 Gagarina St., 603950 Nizhny Novgorod (Russian Federation); Toivanen, V. [European Organization for Nuclear Research (CERN), 1211 Geneva 23 (Switzerland)

    2016-09-15

    The efficiency of the microwave-plasma coupling plays a significant role in the production of highly charged ion beams with electron cyclotron resonance ion sources (ECRISs). The coupling properties are affected by the mechanical design of the ion source plasma chamber and microwave launching system, as well as damping of the microwave electric field by the plasma. Several experiments attempting to optimize the microwave-plasma coupling characteristics by fine-tuning the frequency of the injected microwaves have been conducted with varying degrees of success. The inherent difficulty in interpretation of the frequency tuning results is that the effects of microwave coupling system and the cavity behavior of the plasma chamber cannot be separated. A preferable approach to study the effect of the cavity properties of the plasma chamber on extracted beam currents is to adjust the cavity dimensions. The results of such cavity tuning experiments conducted with the JYFL 14 GHz ECRIS are reported here. The cavity properties were adjusted by inserting a conducting tuner rod axially into the plasma chamber. The extracted beam currents of oxygen charge states O{sup 3+}–O{sup 7+} were recorded at various tuner positions and frequencies in the range of 14.00–14.15 GHz. It was observed that the tuner position affects the beam currents of high charge state ions up to several tens of percent. In particular, it was found that at some tuner position / frequency combinations the plasma exhibited “mode-hopping” between two operating regimes. The results improve the understanding of the role of plasma chamber cavity properties on ECRIS performances.

  13. PLASMA ENERGIZATION

    Science.gov (United States)

    Furth, H.P.; Chambers, E.S.

    1962-03-01

    BS>A method is given for ion cyclotron resonance heatthg of a magnetically confined plasma by an applied radio-frequency field. In accordance with the invention, the radiofrequency energy is transferred to the plasma without the usual attendent self-shielding effect of plasma polarlzatlon, whereby the energy transfer is accomplished with superior efficiency. More explicitly, the invention includes means for applying a radio-frequency electric field radially to an end of a plasma column confined in a magnetic mirror field configuration. The radio-frequency field propagates hydromagnetic waves axially through the column with the waves diminishing in an intermediate region of the column at ion cyclotron resonance with the fleld frequency. In such region the wave energy is converted by viscous damping to rotational energy of the plasma ions. (AEC)

  14. Low Temperature Metal Free Growth of Graphene on Insulating Substrates by Plasma Assisted Chemical Vapor Deposition.

    Science.gov (United States)

    Muñoz, R; Munuera, C; Martínez, J I; Azpeitia, J; Gómez-Aleixandre, C; García-Hernández, M

    2017-03-01

    Direct growth of graphene films on dielectric substrates (quartz and silica) is reported, by means of remote electron cyclotron resonance plasma assisted chemical vapor deposition r-(ECR-CVD) at low temperature (650°C). Using a two step deposition process- nucleation and growth- by changing the partial pressure of the gas precursors at constant temperature, mostly monolayer continuous films, with grain sizes up to 500 nm are grown, exhibiting transmittance larger than 92% and sheet resistance as low as 900 Ω·sq-1. The grain size and nucleation density of the resulting graphene sheets can be controlled varying the deposition time and pressure. In additon, first-principles DFT-based calculations have been carried out in order to rationalize the oxygen reduction in the quartz surface experimentally observed. This method is easily scalable and avoids damaging and expensive transfer steps of graphene films, improving compatibility with current fabrication technologies.

  15. Development of high energy pulsed plasma simulator for plasma-lithium trench experiment

    Science.gov (United States)

    Jung, Soonwook

    To simulate detrimental events in a tokamak and provide a test-stand for a liquid lithium infused trench (LiMIT) device, a pulsed plasma source utilizing a theta pinch in conjunction with a coaxial plasma accelerator has been developed. An overall objective of the project is to develop a compact device that can produce 100 MW/m2 to 1 GW/m2 of plasma heat flux (a typical heat flux level in a major fusion device) in ~ 100 mus (≤ 0.1 MJ/m2) for a liquid lithium plasma facing component research. The existing theta pinch device, DEVeX, was built and operated for study on lithium vapor shielding effect. However, a typical plasma energy of 3 - 4 kJ/m2 is too low to study an interaction of plasma and plasma facing components in fusion devices. No or little preionized plasma, ringing of magnetic field, collisions of high energy particles with background gas have been reported as the main issues. Therefore, DEVeX is reconfigured to mitigate these issues. The new device is mainly composed of a plasma gun for a preionization source, a theta pinch for heating, and guiding magnets for a better plasma transportation. Each component will be driven by capacitor banks and controlled by high voltage / current switches. Several diagnostics including triple Langmuir probe, calorimeter, optical emission measurement, Rogowski coil, flux loop, and fast ionization gauge are used to characterize the new device. A coaxial plasma gun is manufactured and installed in the previous theta pinch chamber. The plasma gun is equipped with 500 uF capacitor and a gas puff valve. The increase of the plasma velocity with the plasma gun capacitor voltage is consistent with the theoretical predictions and the velocity is located between the snowplow model and the weak - coupling limit. Plasma energies measured with the calorimeter ranges from 0.02 - 0.065 MJ/m2 and increases with the voltage at the capacitor bank. A cross-check between the plasma energy measured with the calorimeter and the triple probe

  16. Simulations of a Plasma Thruster Utilizing the FRC Configuration

    Energy Technology Data Exchange (ETDEWEB)

    Rognlien, T. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Cohen, B. I. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-10-10

    This report describes work performed by LLNL to model the behavior and performance of a reverse-field configuration (FRC) type of plasma device as a plasma thruster as summarized by Razin et al. [1], which also describes the MNX device at PPPL used to study this concept.

  17. Paper-based plasma sanitizers

    Science.gov (United States)

    Xie, Jingjin; Chen, Qiang; Suresh, Poornima; Roy, Subrata; White, James F.; Mazzeo, Aaron D.

    2017-05-01

    This work describes disposable plasma generators made from metallized paper. The fabricated plasma generators with layered and patterned sheets of paper provide a simple and flexible format for dielectric barrier discharge to create atmospheric plasma without an applied vacuum. The porosity of paper allows gas to permeate its bulk volume and fuel plasma, while plasma-induced forced convection cools the substrate. When electrically driven with oscillating peak-to-peak potentials of ±1 to ±10 kV, the paper-based devices produced both volume and surface plasmas capable of killing microbes. The plasma sanitizers deactivated greater than 99% of Saccharomyces cerevisiae and greater than 99.9% of Escherichia coli cells with 30 s of noncontact treatment. Characterization of plasma generated from the sanitizers revealed a detectable level of UV-C (1.9 nWṡcm-2ṡnm-1), modest surface temperature (60 °C with 60 s of activation), and a high level of ozone (13 ppm with 60 s of activation). These results deliver insights into the mechanisms and suitability of paper-based substrates for active antimicrobial sanitization with scalable, flexible sheets. In addition, this work shows how paper-based generators are conformable to curved surfaces, appropriate for kirigami-like “stretchy” structures, compatible with user interfaces, and suitable for sanitization of microbes aerosolized onto a surface. In general, these disposable plasma generators represent progress toward biodegradable devices based on flexible renewable materials, which may impact the future design of protective garments, skin-like sensors for robots or prosthetics, and user interfaces in contaminated environments.

  18. Paper-based plasma sanitizers.

    Science.gov (United States)

    Xie, Jingjin; Chen, Qiang; Suresh, Poornima; Roy, Subrata; White, James F; Mazzeo, Aaron D

    2017-05-16

    This work describes disposable plasma generators made from metallized paper. The fabricated plasma generators with layered and patterned sheets of paper provide a simple and flexible format for dielectric barrier discharge to create atmospheric plasma without an applied vacuum. The porosity of paper allows gas to permeate its bulk volume and fuel plasma, while plasma-induced forced convection cools the substrate. When electrically driven with oscillating peak-to-peak potentials of ±1 to ±10 kV, the paper-based devices produced both volume and surface plasmas capable of killing microbes. The plasma sanitizers deactivated greater than 99% of Saccharomyces cerevisiae and greater than 99.9% of Escherichia coli cells with 30 s of noncontact treatment. Characterization of plasma generated from the sanitizers revealed a detectable level of UV-C (1.9 nW⋅cm -2 ⋅nm -1 ), modest surface temperature (60 °C with 60 s of activation), and a high level of ozone (13 ppm with 60 s of activation). These results deliver insights into the mechanisms and suitability of paper-based substrates for active antimicrobial sanitization with scalable, flexible sheets. In addition, this work shows how paper-based generators are conformable to curved surfaces, appropriate for kirigami-like "stretchy" structures, compatible with user interfaces, and suitable for sanitization of microbes aerosolized onto a surface. In general, these disposable plasma generators represent progress toward biodegradable devices based on flexible renewable materials, which may impact the future design of protective garments, skin-like sensors for robots or prosthetics, and user interfaces in contaminated environments.

  19. Dynamical Coupling between Gradients and Transport in Fusion Plasmas

    Science.gov (United States)

    Hidalgo, C.; Silva, C.; Carreras, B. A.; van Milligen, B.; Figueiredo, H.; García, L.; Pedrosa, M. A.; Gonçalves, B.; Alonso, A.

    2012-02-01

    The dynamical coupling between density gradients and particle transport has been investigated using similar experimental tools in the plasma boundary of different tokamak (JET, ISTTOK) and stellarator (TJ-II) devices, showing that the size of turbulent events is minimum in the proximity of the most probable density gradient. Experimental results were found to be consistent with results from two very different models of plasma turbulence and transport. The present findings, common to several plasma devices, suggest the importance of self-regulation mechanisms between plasma transport and gradients in fusion devices.

  20. Multi-Scale Investigation of Sheared Flows In Magnetized Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Edward, Jr., Thomas [Auburn Univ., Auburn, AL (United States)

    2014-09-19

    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.

  1. Scalable devices

    KAUST Repository

    Krüger, Jens J.

    2014-01-01

    In computer science in general and in particular the field of high performance computing and supercomputing the term scalable plays an important role. It indicates that a piece of hardware, a concept, an algorithm, or an entire system scales with the size of the problem, i.e., it can not only be used in a very specific setting but it\\'s applicable for a wide range of problems. From small scenarios to possibly very large settings. In this spirit, there exist a number of fixed areas of research on scalability. There are works on scalable algorithms, scalable architectures but what are scalable devices? In the context of this chapter, we are interested in a whole range of display devices, ranging from small scale hardware such as tablet computers, pads, smart-phones etc. up to large tiled display walls. What interests us mostly is not so much the hardware setup but mostly the visualization algorithms behind these display systems that scale from your average smart phone up to the largest gigapixel display walls.

  2. Physics of semiconductor devices

    Energy Technology Data Exchange (ETDEWEB)

    Prew, B.A.

    1975-09-01

    The properties of semiconductors which make them important in the electronic devices industry, and how these properties are controlled by doping, are described. The physics and applications of p-n and other junction devices, and of bulk effect devices are discussed. Avalanche devices, optical devices, solar cells, Schottky barriers, MOS devices, heterojunctions, photoconductors, and transferred electron devices are considered.

  3. Experimental investigation of plasma relaxation using a compact coaxial magnetized plasma gun in a background plasma

    Science.gov (United States)

    Zhang, Yue; Lynn, Alan; Gilmore, Mark; Hsu, Scott; University of New Mexico Collaboration; Los Alamos National Laboratory Collaboration

    2013-10-01

    A compact coaxial plasma gun is employed for experimental studies of plasma relaxation in a low density background plasma. Experiments are being conducted in the linear HelCat device at UNM. These studies will advance the knowledge of basic plasma physics in the areas of magnetic relaxation and space and astrophysical plasmas, including the evolution of active galactic jets/radio lobes within the intergalactic medium. The gun is powered by a 120pF ignitron-switched capacitor bank which is operated in a range of 5-10 kV and ~100 kA. Multiple diagnostics are employed to investigate plasma relaxation process. Magnetized Argon plasma bubbles with velocities ~1.2Cs and densities ~1020 m-3 have been achieved. Different distinct regimes of operation with qualitatively different dynamics are identified by fast CCD camera images, with the parameter determining the operation regime. Additionally, a B-dot probe array is employed to measure the spatial toroidal and poloidal magnetic flux evolution to identify detached plasma bubble configurations. Experimental data and analysis will be presented.

  4. Practical microwave electron devices

    CERN Document Server

    Meurant, Gerard

    2013-01-01

    Practical Microwave Electron Devices provides an understanding of microwave electron devices and their applications. All areas of microwave electron devices are covered. These include microwave solid-state devices, including popular microwave transistors and both passive and active diodes; quantum electron devices; thermionic devices (including relativistic thermionic devices); and ferrimagnetic electron devices. The design of each of these devices is discussed as well as their applications, including oscillation, amplification, switching, modulation, demodulation, and parametric interactions.

  5. Shock Propagation and Supersonic Drag in Low Temperature Plasmas

    National Research Council Canada - National Science Library

    Miles, Richard

    1998-01-01

    .... In addition, atmospheric plasmas could influence flow control devices, electromagnetic attenuation, and hypersonic propulsion systems. As a consequence, the formation of such plasmas in atmospheric pressure environments, and the study of the properties of these plasmas, are of significant national interest.

  6. 20. AINSE plasma science and technology conference. Conference handbook

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The 20th AINSE plasma science and technology conference was held at Flinders University of South Australia on 13-14 February 1995. Topics under discussion included plasma physics studies, current status of rotamak devices, plasma processing and material studies. The handbook contains the conference program, 54 abstracts and a list of participants.

  7. Plasma chromograninx

    DEFF Research Database (Denmark)

    Goetze, Jens P; Hilsted, Linda M; Rehfeld, Jens F

    2014-01-01

    Cardiovascular risk assessment remains difficult in elderly patients. We examined whether chromogranin A (CgA) measurement in plasma may be valuable in assessing risk of death in elderly patients with symptoms of heart failure in a primary care setting. A total of 470 patients (mean age 73 years......) were followed for 10 years. For CgA plasma measurement, we used a two-step method including a screening test and a confirmative test with plasma pre-treatment with trypsin. Cox multivariable proportional regression and receiver-operating curve (ROC) analyses were used to assess mortality risk...... of follow-up showed significant additive value of CgA confirm measurements compared with NT-proBNP and clinical variables. CgA measurement in the plasma of elderly patients with symptoms of heart failure can identify those at increased risk of short- and long-term mortality....

  8. Plasma Cleaning

    Science.gov (United States)

    Hintze, Paul E.

    2016-01-01

    NASA's Kennedy Space Center has developed two solvent-free precision cleaning techniques: plasma cleaning and supercritical carbon dioxide (SCCO2), that has equal performance, cost parity, and no environmental liability, as compared to existing solvent cleaning methods.

  9. Turbulence in a cusp Q device

    DEFF Research Database (Denmark)

    D'Angelo, N.; Pécseli, Hans; Petersen, P. I.

    1974-01-01

    Spectral measurements are reported of plasma turbulence in the Cs plasma of a Q device, modified to a magnetic cusp geometry. The excitation mechanism for the fluctuations appears to be the centrifugal instability discussed by Chen. A transition from an f−5 to an f−3 power spectrum is observed...... as one moves from the hot plates to the midplane of the cusp. ©1974 American Institute of Physics...

  10. Plasma confinement

    CERN Document Server

    Hazeltine, R D

    2003-01-01

    Detailed and authoritative, this volume examines the essential physics underlying international research in magnetic confinement fusion. It offers readable, thorough accounts of the fundamental concepts behind methods of confining plasma at or near thermonuclear conditions. Designed for a one- or two-semester graduate-level course in plasma physics, it also represents a valuable reference for professional physicists in controlled fusion and related disciplines.

  11. CLOSURE DEVICE

    Science.gov (United States)

    Linzell, S.M.; Dorcy, D.J.

    1958-08-26

    A quick opening type of stuffing box employing two banks of rotatable shoes, each of which has a caraming action that forces a neoprene sealing surface against a pipe or rod where it passes through a wall is presented. A ring having a handle or wrench attached is placed eccentric to and between the two banks of shoes. Head bolts from the shoes fit into slots in this ring, which are so arranged that when the ring is rotated a quarter turn in one direction the shoes are thrust inwardly to cramp the neopnrene about the pipe, malting a tight seal. Moving the ring in the reverse direction moves the shoes outwardly and frees the pipe which then may be readily removed from the stuffing box. This device has particular application as a closure for the end of a coolant tube of a neutronic reactor.

  12. Plasma transport near material boundaries

    Energy Technology Data Exchange (ETDEWEB)

    Singer, C.E.

    1985-06-01

    The fluid theory of two-dimensional (2-d) plasma transport in axisymmetric devices is reviewed. The forces which produce flow across the magnetic field in a collisional plasma are described. These flows may lead to up-down asymmetries in the poloidal rotation and radial fluxes. Emphasis is placed on understanding the conditions under which the known 2-d plasma fluid equations provide a valid description of these processes. Attempts to extend the fluid treatment to less collisional, turbulent plasmas are discussed. A reduction to the 1-d fluid equations used in many computer simulations is possible when sources or boundary conditions provide a large enough radial scale length. The complete 1-d fluid equations are given in the text, and 2-d fluid equations are given in the Appendix.

  13. Recent results with NBI plasmas in TJ-II stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Liniers, M.; Ascasibar, E.; Estrada, T.; Tabares, F. L.; Acedo, M.; Alonso, J.; Balbin, R.; Blanco, B.; Branas, B.; Cappa, A.; Carrasco, R.; Castejon, F.; Fernandez, A.; Fontdecaba, J. M.; Fuentes, C.; Garcia, A.; Garcia-Cortes, I.; Guasp, J.; Hidalgo, A.; Hidalgo, C.; Jimenez, R.; Lopez-Bruna, D.; Lopez-Fraguas, A.; Marcon, G.; McCarthy, K. J.; Medina, F.; Medrano, M.; Ochando, M.; Pastor, I.; Pedrosa, M. A.; Rapisarda, D.; Sanchez, E.; Sanchez, M.; Sanchez, J.; Tafalla, D.; Wolfers, G.; Zurro, B.

    2005-07-01

    During the last experimental campaign Neutral Beam Injection into TJ-II plasmas has been available, with a single H0 beam aiming tangentially in the Co-direction. As the ion source conditioning was improved along the campaign, the injected power increased from 200 kW to 400 kW port-through, and the beam energy was raised from 26 kV to 30 kV [1]. Target plasmas are created by ECR heating, using two gyrotrons of 200 kW power, at the second harmonic frequency (53 GHz). The injection direction of the microwaves can be steered by means of movable mirrors placed inside the vacuum chamber, making it possible to vary the power deposition region from the plasma core (on-axis) to the outer regions near ?=0.5 (off-axis). The plasma temperature and density profiles obtained with on-axis or off axis ECRH are seen to differ widely, allowing us to study the neutral beam absorption in two qualitatively different plasma target scenarios. Other factors affecting the plasma profiles have also been investigated, such as the magnetic configuration or the OH-driven current. TJ-II has the capability of varying the magnetic configuration by changing the ratio of the current through the circular and helical conductors that form the Central Conductor. The iota values can be swept between 0.9 and 2.2 and the magnetic well between -1% and 6% giving rise to configurations with different confinement properties. A negative OH driven current has the effect of increasing the magnetic shear value, allowing low-order rationals in the central region which have been seen to modify density profiles in ECH plasmas. In most NBI discharges the central plasma density increases continuously from ECH typical values below 1.1 x 10 19 m-3 up to 6.5 x 10 19 m-3, as the beam is injected, until a thermal collapse that terminates the discharge is reached. So far, density control with NBI plasmas has not been achieved, although an improved behaviour is observed with wall cleaning. (Author)

  14. Carbon based prosthetic devices

    Energy Technology Data Exchange (ETDEWEB)

    Devlin, D.J.; Carroll, D.W.; Barbero, R.S.; Archuleta, T. [Los Alamos National Lab., NM (US); Klawitter, J.J.; Ogilvie, W.; Strzepa, P. [Ascension Orthopedics (US); Cook, S.D. [Tulane Univ., New Orleans, LA (US). School of Medicine

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to evaluate the use of carbon/carbon-fiber-reinforced composites for use in endoprosthetic devices. The application of these materials for the metacarpophalangeal (MP) joints of the hand was investigated. Issues concerning mechanical properties, bone fixation, biocompatibility, and wear are discussed. A system consisting of fiber reinforced materials with a pyrolytic carbon matrix and diamond-like, carbon-coated wear surfaces was developed. Processes were developed for the chemical vapor infiltration (CVI) of pyrolytic carbon into porous fiber preforms with the ability to tailor the outer porosity of the device to provide a surface for bone in-growth. A method for coating diamond-like carbon (DLC) on the articulating surface by plasma-assisted chemical vapor deposition (CVD) was developed. Preliminary results on mechanical properties of the composite system are discussed and initial biocompatibility studies were performed.

  15. The target for the new plasma/wall experiment Magnum-PSI

    NARCIS (Netherlands)

    van den Berg, M. A.; Brons, S.; Kruijt, O. G.; Scholten, J.; Pasquet, R.; Smeets, P. H. M.; Schweer, B.; De Temmerman, G.

    2011-01-01

    The construction of Magnum-PSI is in its final stage. The aim is to provide a controlled and highly accessible linear plasma device to perform the basic plasma-surface interaction research needed for the design of the plasma facing components of future fusion devices. This contribution will focus on

  16. “A noite da cultura no reino da técnica”. Recensão de crise no castelo da cultura. Das estrelas para os ecrãs, de Moisés de Lemos Martins

    OpenAIRE

    Correia, Maria da Luz

    2011-01-01

    Em Crise no Castelo da Cultura, Das Estrelas para os Ecrãs, último ensaio de Moisés de Lemos Martins que reúne o trabalho de uma dezena de anos em estudos da comunicação e teoria da cultura, o sociólogo debruça-se sobre a crise do humano, o mal de vivre contemporâneo, decorrente da experiência tecnológica – da comunicação em rede às biotecnologias – , e da conversão das nossas vidas à lógica do mercado global. Na esteira daquilo que designa por “pensamento da diferença” – de Ni...

  17. Remote operation of the vertical plasma stabilization @ the GOLEM tokamak for the plasma physics education

    Energy Technology Data Exchange (ETDEWEB)

    Svoboda, V., E-mail: svoboda@fjfi.cvut.cz [Faculty of Nuclear Sciences and Physical Engineering CTU Prague, CZ-115 19 (Czech Republic); Kocman, J.; Grover, O. [Faculty of Nuclear Sciences and Physical Engineering CTU Prague, CZ-115 19 (Czech Republic); Krbec, J.; Stöckel, J. [Faculty of Nuclear Sciences and Physical Engineering CTU Prague, CZ-115 19 (Czech Republic); Institute of Plasma Physics AS CR, CZ-182 21 Prague (Czech Republic)

    2015-10-15

    Graphical abstract: * Understandable remote operation of a vertical plasma position control system in the tokamak GOLEM for educational purposes.* Two combinable modes of real-time plasma position control: position based feedback and a pre-defined waveform.* More than 20% plasma life prolongation with plasma position control in feedback mode. - Highlights: • Understandable remote operation of a vertical plasma position control system in the tokamak GOLEM for educational purposes. • Two combinable modes of real-time plasma position control: position based feedback and a pre-defined waveform. • More than 20% plasma life prolongation with plasma position control in feedback mode. - Abstract: The GOLEM tokamak at the Czech Technical University has been established as an educational tokamak device for domestic and foreign students. Remote participation in the scope of several laboratory practices, plasma physics schools and workshops has been successfully performed from abroad. A new enhancement allowing understandable remote control of vertical plasma position in two modes (i) predefined and (ii) feedback control is presented. It allows to drive the current in the stabilization coils in any time-dependent scenario, which can include as a parameter the actual plasma position measured by magnetic diagnostics. Arbitrary movement of the plasma column in a vertical direction, stabilization of the plasma column in the center of the tokamak vessel as well as prolongation/shortening of plasma life according to the remotely defined request are demonstrated.

  18. Divertor for a linear fusion device

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D. D. [Lawrence Livermore National laboratory, Livermore, CA, 94550 (United States); Yushmanov, P. N.; Barnes, D. C.; Putvinski, S. V. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, CA 92688 (United States)

    2016-03-25

    Linear fusion devices can use large magnetic flux flaring in the end tanks to reduce the heat load on the end structures. In order to reduce parallel electron heat loss, one has to create conditions where the neutral gas density in the end tanks is low, as otherwise cold electrons produced by the ionization of the neutrals would cool down the core plasma electrons. The processes determining the neutral gas formation and spatial distribution are analysed for the case where neutrals are formed by the surface recombination of the outflowing plasma. The conditions under which the cooling of the core plasma is negligible are formulated.

  19. Plasma-Materials Interactions Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Uckan, T.

    1986-11-01

    The Plasma-Materials Interactions Test Facility (PMITF), recently designed and constructed at Oak Ridge National Laboratory (ORNL), is an electron cyclotron resonance microwave plasma system with densities around 10/sup 11/ cm/sup -3/ and electron temperatures of 10-20 eV. The device consists of a mirror cell with high-field-side microwave injection and a heating power of up to 0.8 kW(cw) at 2.45 GHz. The facility will be used for studies of plasma-materials interactions and of particle physics in pump limiters and for development and testing of plasma edge diagnostics.

  20. Development of TPF-1 plasma focus for education

    Science.gov (United States)

    Picha, R.; Promping, J.; Channuie, J.; Poolyarat, N.; Sangaroon, S.; Traikool, T.

    2017-09-01

    The plasma focus is a device that uses high voltage and electromagnetic force to induce plasma generation and acceleration, in order to cause nuclear reactions. Radiation of various types (X-ray, gamma ray, electrons, ions, neutrons) can be generated using this method during the pinch phase, thus making the plasma focus able to serve as a radiation source. Material testing, modification, and identification are among the current applications of the plasma focus. Other than being an alternative option to isotopic sources, the plasma focus, which requires multidisciplinary team of personnel to design, operate, and troubleshoot, can also serve as an excellent learning device for physics and engineering students in the fields including, but not limited to, plasma physics, nuclear physics, electronics engineering, and mechanical engineering. This work describes the parameters and current status of Thai Plasma Focus 1 (TPF-1) and the characteristics of the plasma being produced in the machine using a Rogowski coil.