GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Various divertor biasing configurations and improved divertor performance with biasing on Tokamak de Varennes (TdeV)* (1994)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 1 (1994), S. 1497-1502 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Electrically insulated divertor plates are used on TdeV (Tokamak de Varennes) [18th EPS Conference on Controlled Fusion and Plasma Physics Berlin (European Physical Society, Petit-Lancy, 1991), Vol. 15C, Part I, pp. 1–141] to produce various biasing configurations, which can be decomposed into two basic modes. Plasma biasing, with a radial electric field Er in the scrape-off layer (SOL), is most promising for divertor applications. The Er field is produced with a particular divertor plate geometry, causing a nonambipolar radial current and a particle flow in the Er×BT direction, toward one of the divertors (the active divertor). The pressure and impurity retention in the active divertor are shown, in the Ohmic regime, to be strongly increased by biasing. He exhaust through this divertor is increased by a factor of almost 3 with modest biasing voltages and currents scalable to larger devices. Biasing also modifies the power repartition between the divertors, with the active divertor also receiving a larger fraction of the power.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.870699
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Optimization of the extracted current density from the high energy diagnostic neutral beam injector of TdeV : Proceedings of the eleventh topical conference on high temperature plasma diagnostics (1997)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 68 (1997), S. 289-291 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Development of a high energy (40 kV, 1 A) neutral beam injector for diagnostic applications on TdeV is in progress. The injector operates with its source at ground potential and the neutralizer canal at ≤−40 kV. The electrons in the neutralizer canal are retained by an electrostatic trap. The residual ions are collected near ground potential. Several diagnostics, including calorimetry, spectroscopy and a scanning multipin open probe array, are used to study the beam characteristics on its test stand. Hall probes and voltage dividers coupled with fiber optic links are used to optimize the efficiency of the extraction system, the electron trap, and the residual ion collection units. In its first stage of development, the injector has been optimized for operation with a single hydrogen beamlet. A beamlet divergence of less than 0.5 degrees was obtained. Up to 75 mA of ion current at 35 kV was extracted. The addition of another six extraction holes boosted the total extracted current to more than 600 mA at 36 kV. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1147739
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Tokamak de Varenne's diagnostic neutral beam injector : Proceedings of the 7th international conference on ion sources (1998)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 69 (1998), S. 923-925 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A fully automated and remote controlled neutral beam injector has been designed, built, and characterized on a test stand for use as a diagnostic aid on Tokamak de Varennes (TdeV). The injector has a duoPIGatron ion source with a LaB6 coaxial cathode. A cusped magnetic field surrounding the plasma chamber is used to enhance the plasma confinement. The beam current is modulated by switching the arc current, and it has a 70 μs rise time. Two, in-house-built, titanium sublimation pumps provide up to 16 000 l s−1 pumping capacity for differential pumping between the source and the tokamak. The injector operates with its source at ground potential, and its neutralizer canal at a negative potential |Vb|≤40 kV. An electrostatic trap biased to −6 kV with respect to the neutralizer canal retains the electrons in the neutralizer. The residual ions are collected on an ion collector that is biased to −5 kV. The design of the extraction system and the electrostatic trap was optimized with a numerical code. The injector has been operated with hydrogen and helium beams. A multi-aperture three-grid extraction system provides up to 2.4 A of proton or 1.2 A of He+ current. The maximum average proton current density extracted from the 19 extraction holes was 650 mA cm−2 at 35 kV extraction voltage, which was obtained with 60 A of arc current. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1148702
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Design of an ion temperature diagnostic based on neutral beam scattering (1986)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 57 (1986), S. 1792-1793 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Small-angle neutral beam scattering will be used on the STOR-M tokamak to obtain space and time-resolved measurements of the ion temperature. Advantages of the technique and experimental considerations leading to the design are discussed. It is expected that a 20–30-keV helium beam of 35–65-A/m2 current density together with a large area chevron channel-plate detector and automatic data handling will allow direct determination of ion temperatures at an accuracy of 10%, a temporal resolution of 40 μs, and a spatial resolution better than 1 cm.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1139184
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Design of the motional Stark effect diagnostic in FTU : Papers from the thirteenth topical conference on high temperature plasma diagnostics (2001)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 72 (2001), S. 1015-1017 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: This article reports on the design of the motional Stark effect diagnostic (MSE) for the Frascati Tokamak Upgrade tokamak (Rmaj=93 cm, rmin=33 cm, BT〈8 T). The attenuation and emissivity of a diagnostic hydrogen beam have been estimated for typical discharges to assess the feasibility of the diagnostic. Due to the geometrical constraints the beam direction and the polarimeter lines of sight lie on a vertical plane on the same horizontal port. This layout has the advantage of a more convenient projection of the polarization vector on the line of sight, which increases the sensitivity of the measure. The relay optics has been designed so as to minimize Faraday rotation effects which would perturb the measurements. Two polarimeters based on different modulating techniques are compared and discussed. The first one makes use of photoelastic modulators. The second employs a fast rotating retarder plate. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1319610
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Bolometric diagnostics in Tokamak de Varennes (1996)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 67 (1996), S. 2202-2206 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Radiative power from the main and divertor plasmas of Tokamak de Varennes (TdeV) is measured using a compact bolometric diagnostic. The diagnostic is comprised of a multichannel pin-hole camera and several collimated bolometers. The electronic circuit of the bolometers permits remotely controlled in situ calibration of the detectors. The pin-hole camera, with its 17 channels of thermistor bolometers, monitors the plasma poloidal cross section horizontally. In the same camera housing reside a pair of wide angle metal film bolometers that measure the total radiative losses from the main plasma, and a 16 channel x-ray-ultraviolet photodiode array. Five collimated thermistor bolometers project the vertical view of the plasma poloidal cross section. The divertor plasma losses are monitored by six pairs of collimated thermistor bolometers installed at different toroidal locations. One pair in the lower and three pairs in the upper divertor chamber measure the global power loss from the plasma in front of the outboard divertor plates. Two other pairs of bolometers located just behind the inclined divertor plate, measure the poloidal distribution of the plasma losses from the divertor plate to the X point with an improved spatial resolution. Three divertor bolometers and one of the wide angle bolometers in the main plasma are covered with MgF2 windows, for rough spectral analysis of the radiative power loss. Examples of bolometric measurements of the radiative loss and its distribution in the TdeV during plasma detachment, plasma biasing and lower hybrid current drive and heating experiments are given. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1147037
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Improved confinement and edge plasma fluctuations in the STOR-M tokamak (1992)
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 4 (1992), S. 3277-3284 
    Details
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: An improved Ohmic confinement phase has been observed in the STOR-M tokamak [Plasma Physics and Controlled Nuclear Fusion Research, 1988 (International Atomic Energy Agency, Vienna, 1989), Vol. 1, p. 323] after application of a turbulent heating (TH) pulse. This improved Ohmic confinement phase is characterized by (a) increased n¯e, (b) reduced Hα radiation from the edge, (c) reduced density and magnetic fluctuations at the edge, (d) a steeper density profile at the edge, and (e) a more negative radial electric field. Almost complete suppression of sawtooth oscillations during the improved confinement phase has also been observed. A linear dispersion relation describes the density and magnetic fluctuations in the frequency range up to 350 kHz. In the region r〈a (r(approximately-greater-than)a) the propagation direction of the density fluctuations is in the electron (ion) diamagnetic direction. The reduction of rms density and magnetic fluctuations after the TH pulse is largely due to suppression of relatively high frequency (≤500 kHz) components. The density fluctuations (ñ/ne) in the scrape-off layer remain intact after the pulse.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.860383
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    A Technique for Sorting Rat Gonadotropes using Anti-LH or Anti-FSH Antibodies Covalently attached to Magnetic Beads (1995)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neuroendocrinology 7 (1995), S. 0 
    Details
    ISSN: 1365-2826
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: A technique for sorting live LH- and FSH-secreting cells was developed. After enzymatic dispersion, a suspension of pituitary cells from male rats castrated 7 days earlier was incubated in potassium chloride (KCI 50 mmol/l) for 30 min and gonadotropin outflow was provoked. Then, considering either LH or FSH as temporary surface markers, we positively selected the secreting cells by means of antibodies toward either LH (anti-LH beads) or FSH (anti-FSH beads) covalently attached to magnetic beads. The spontaneous secretion of LH and FSH overnight and the release induced by KCI the following morning were calculated. A population enriched in gonadotropes (16% of the total) able to secrete both gonadotropins was selected by means of anti-LH beads; this released 7 times as much LH as non-selected cells. A similar population (14% of the total) was selected by means of anti-FSH-coated beads; this produced 3.3 times as much LH as non-selected cells.In some experiments, the cells not previously sorted with anti-LH-coated beads were further incubated in the presence of anti-FSH beads, in an attempt to isolate a population secreting only FSH. A limited number of cells were sorted (6% of the total cells), able to produce both gonadotropins, but with a lower LH/FSH ratio.Similarly, those cells excluded by the selection with anti-FSH beads were further incubated with anti-LH beads, with a view to obtaining only-LH-secreting cells. However, both gonadotropins were still secreted by these cells (8% of the total), which had the highest LH/FSH ratio.In conclusion, fractions from castrated male rats that are enriched in gonadotropes contain cells that secrete both gonadotropins in vitro. The secretion of LH is prevalent. However, differences in the LH/FSH ratio between the populations sorted and changes from spontaneous to stimulated release are observed. This suggests that some gonadotropes might ‘specialize’ in releasing LH and others in releasing both LH and FSH.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2826.1995.tb00808.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Improvements to the accuracy of measurements of NO"2 by zenith-sky visible spectrometers
    Amsterdam : Elsevier
    Journal of Quantitative Spectroscopy and Radiative Transfer 52 (1994), S. 649-657 
    Details
    ISSN: 0022-4073
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0022-4073(94)90031-0
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Improvements to the accuracy of zenith-sky measurements of total ozone by visible spectrometers
    Amsterdam : Elsevier
    Journal of Quantitative Spectroscopy and Radiative Transfer 52 (1994), S. 639-648 
    Details
    ISSN: 0022-4073
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0022-4073(94)90030-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...