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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Methods of measuring the properties of ionized gases at high frequencies

January 1952 (has links)
Sanborn C. Brown, David J. Rose. / I. Measurements of Q / Sanborn C. Brown, David J. Rose -- II. Measurement of electric field / David J. Rose, Sanborn C. Brown -- III. Measurement of discharge admittance and electron density / Sanborn C. Brown, David J. Rose -- IV. A null method of measuring the discharge admittance / Lawrence Gould, Sanborn C. Brown. / January 22, 1952 -- v.1. / Includes bibliographies. / Army Signal Corps Contract no. DA36-039 sc-100, Project no. 8-102B-0. Dept. of the Army Project no. 3-99-10-022.
192

Probe studies of energy distributions and radial potential variations in a low-pressure mercury arc

January 1952 (has links)
R. M. Howe. / "January 18, 1952." "This report is based on a doctoral thesis in the Department of Physics, Massachusetts Institute of Technology, 1950." / Bibliography: p. 26. / Army Signal Corps Contract No. DA36-039 sc-100 Project No. 8-102B-0. Dept. of the Army Project No. 3-99-10-022.
193

Electron density distribution in a high frequency discharge in the presence of plasma resonance

January 1951 (has links)
W.P. Allis, Sanborn C. Brown [and] Edgar Everhart. / "July 16, 1951." / Bibliography: p. 9. / Army Signal Corps Contract No. DA36-039 sc-100 Project No. 8-102B-0. Dept. of the Army Project No. 3-99-10-022.
194

Methods of measuring the properties of ionized gases at microwave frequencies

January 1949 (has links)
David J. Rose ... [et al.]. / "October 17, 1949." / Army Signal Corps Contract No. W-36-039 sc-32037 Project No. 102B. Dept. of the Army Project No. 3-99-10-022.
195

Methods of measuring the properties of ionized gases at microwave frequencies

January 1948 (has links)
Sanborn C. Brown ... [et al.]. / "May 17, 1948." / Includes bibliographical references. / Army Signal Corps Contract No. W-36-039 sc-32037.
196

Surface induced dissociation of small molecules and peptides utilizing delayed extraction with tandem time-of-flight mass spectrometery [sic] /

Haney, Lisa L. January 1999 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
197

Surface induced dissociation of small molecules and peptides utilizing delayed extraction with tandem time-of-flight mass spectrometery [sic]

Haney, Lisa L. January 1999 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
198

Impurity transport studies on Alcator C-Mod tokamak using charge exchange recombination spectroscopy

Bespamyatnov, Igor Olegovich, 1978- 04 September 2012 (has links)
A Charge-Exchange Recombination Spectroscopy (CXRS) diagnostic has been installed on Alcator C-Mod to study the transport of light impurities in plasma. The system provides spatially (1 cm) and temporally (12.5 msec) resolved measurements of the impurity density, temperature and flow velocities of the particular impurity. Two optical arrays: poloidal (19 channels) and toroidal (10 channels), collect the light emitted from excited impurity ion populated by charge exchange process from the Diagnostic Neutral Beam (DNB) particle. The attention of this dissertation is focused on the B⁴⁺ (n = 7 [-->] 6) spectral line emitted by B⁴⁺ ion formed in the following charge exchange reaction (H⁰ + B⁵⁺ [-->] H+ + B⁴⁺*). A complex spectral model was developed to simulate emission. The high magnetic fields of C-Mod result in broad Zeeman patterns which must be taken into account for the interpretation of the line shift and broadening in terms of impurity ion velocity and temperature. After the spectral line fitting and careful identification of the charge exchange component, the calculated Doppler broadening and shifts of the spectral line profile yield information on the ion temperature and rotation. Together with the calculation of the beam density, the absolute calibration of the CXRS optical system provides us with B⁵⁺ density measurement capabilities. One of the main objectives of this work was to use the acquired impurity density, temperature and flow velocity profiles to investigate plasma transport behavior and infer the radial electric field E[subscript R] from plasma force balance equation. The focus here was placed on the region of the Internal Transport Barrier (ITB) formation 0.35 < p < 0.8. Radial electric field E[subscript R] is readily calculated in the region of the ITB foot using measured B⁵⁺ profiles. ExB velocity shearing turbulence stabilization are believed to play an important role in the physics of the ITB formation. The computed E[subscript R] profiles demonstrated the large difference between the H-mode and ITB discharges. Linear gyrokinetic stability analysis (GS2) demonstrated that shearing rate w[subscript ExB] prevails over the linear Ion Temperature Gradient (ITG) growth rates [gamma subscript max] in the region where ITB forms. / text
199

A self-consistent model of helicon discharge

Chen, Guangye, 1976- 06 September 2012 (has links)
We developed a self-consistent model of helicon discharges, motivated by a number of applications. One example is a plasma-based space propulsion system that employs a helicon discharge as its plasma source. Our study of helicon discharges involves two steps. An electro-magnetic wave solver is first developed to study wave phenomena and power deposition. In this work, we model a resonant response of the discharge observed in a recent experiment. The radially localized helicon (RLH) wave is identified as the primary mechanism of rf-power deposition into the plasma. The second step is to take into account electron heat transfer and ion transport so that a self-consistent simulation can be performed. As a case study of validating the model, we simulated one of Boswell’s early experiment in which a jump of plasma density in a scan of external magnetic field is observed. Calculation shows that a classical heat transport is unable to sustain the plasma density profile observed in the experiment. Solutions comparable to the experiment are obtained only when extra heat conductivity is used. The density profiles and excited wave-lengths are in good agreement with the experiment. Especially, the dual-stable solution of the simulation supports the observed plasma density jump. / text
200

Rotating mirror plasmas in the quest of magnetofluid states

Quevedo, Hernan Javier 28 August 2008 (has links)
Not available / text

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