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in creator/contributor: "Zuhr, R.A."

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Characterization of the TEXTOR plasma edge using deposition probe techniques

Carbon and single crystal silicon passive deposition probes were used to measure the characteristics of the plasma edge region of the TEXTOR tokamak. Analysis of the probes was done by Rutherford backscattering for impurities and nuclear reaction analysis and elastic recoil detection for hydrogen isotopes. Plasma fluxes and energies in the edge were measured using probe techniques. The principal impurities in the plasma edge were determined and their behavior as a function of time and position … more

Date: October 1, 1983

Creator: Zuhr, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Accelerator-based plasma-wall interaction studies on the TEXTOR tokamak

Deposition probes are commonly used to determine plasma edge characteristics in tokamaks. Such probes are frequently analyzed using accelerator-based techniques and can yield information on impurity fluxes, hydrogen fluxes and energies, and surface erosion rates in the plasma edge. Several types of deposition probes have been employed to investigate the plasma edge region of the TEXTOR tokamak in Juelich, FRG. TEXTOR is a moderate size tokamak (major radius = 1.75 m) that is capable of 2 to 3 s… more

Date: September 1, 1984

Creator: Zuhr, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Weight change measurements of erosion/deposition at beryllium limiter tiles in ISX-B

The weight changes of Be tiles which functioned as a rail limiter in ISX-B for more than 3500 beam-heated discharges have been determined. The net weight loss for the limiter was 2.0 g, with the central tiles losing a total of 3.2 g and inboard tiles gaining 1.2 g. The weight loss is attributed primarily to the release of Be droplets as a result of limiter surface melting. The weight gains resulted from an inward flow of molten material along the limiter surface. The results indicate high erosi… more

Date: July 1, 1985

Creator: Roberto, J.B.; Edmonds, P.H.; England, A.C.; Gabbard, A. & Zuhr, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Pump limiter studies on the Heliotron-E device

Particle control with pump limiters has been successfully demonstrated in a variety of tokamaks. This experiment has obtained, for the first time, experimental data on pump limiter operation in a heliotron configuration. A movable pump limiter module was installed on a horizontal midplane port of Heliotron-E. The limiter assembly consists of a TiC-coated graphite head with single-sided particle collection and active pumping. The location of the limiter is varied from near the vacuum vessel wall… more

Date: May 1, 1986

Creator: Hillis, D.L.; Mioduszewski, P.K.; Zuhr, R.A.; Clausing, R.E.; Baity, F.W.; Fowler, R.H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Formation of aluminum films on silicon by ion beam deposition: A comparison with ionized cluster beam deposition

The direct ion beam deposition (IBD) technique has been used to study the formation of oriented aluminum films on single crystal silicon substrates. In the IBD process, thin film growth is accomplished by decelerating a magnetically-analyzed ion beam to low energies (10--200 eV) for direct deposition onto the substrate under UHV conditions. The energy of the incident ions can be selected to provide the desired growth conditions, and the mass analysis ensures good beam purity. The aluminum on si… more

Date: January 1, 1990

Creator: Zuhr, R.A.; Haynes, T.E.; Galloway, M.D. (Oak Ridge National Lab., TN (USA)); Tanaka, S.; Yamada, A. & Yamada, I. (Kyoto Univ. (Japan). Ion Beam Engineering Lab.)

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Surface probe measurements in ISX-B and EBT-S

Surface deposition probe techniques have been shown to be an effective means of determining the characteristics of the plasma edge region of magnetic confinement devices. Experimental results on ISX-B and EBT-S have led to a consistent picture of the edge plasma and the dominant impurity introduction mechanisms. This picture is supported by numerous other measurements and emphasizes the importance of concentrating several techniques on the complex problems of plasma fusion.

Date: December 1, 1982

Creator: Zuhr, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Structure and Electrochemical Properties of LiMn2O4 Thin Films

The structure and electrochemical properties of LiMn{sub 2}O{sub 4} films depend upon the deposition and annealing conditions. Films which were deposited by rf magnetron sputtering of LiMn{sub 2}O{sub 4} in Ar + N{sub 2} gas mixtures and annealed in O{sub 2} at temperatures between 400 to 1000{degrees}C had the cubic spinel structure with an a-axis length that increased linearly from 8.13 to 8.25 {Angstrom} with increasing anneal temperature. Thin-film lithium cells with cathodes of different a… more

Date: November 1, 1998

Creator: Bates, J.B.; Ueda, A. & Zuhr, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

3d-Metal Doped into LiMn2O4 Thin Films

3d-metal (Me) doped LiMn{sub 2}O{sub 4} thin films were deposited by rf magnetron sputtering of Li[Mn{sub 1.9}Me{sub 0.1}]O{sub 4} targets in Ar + N{sub 2} and Ar + O{sub 2} gas mixtures and annealed at 750{degrees}C in O{sub 2} for 1 h. From XRD measurements, the structure of the Me-doped thin film was dependent upon the element and the deposition conditions. The doping level of Me/Mn of cubic phase was less than 0.1 by EDX measurements. The Ti-LiMn{sub 2}O{sub 4} films exhibited a capacity cl… more

Date: November 1, 1998

Creator: Bates, J.B.; Ueda, A. & Zuhr, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ionic conductivities of lithium phosphorus oxynitride glasses, polycrystals, and thin films

Various lithium phosphorus oxynitrides have been prepared in the form of glasses, polycrystals, and thin films. The structures of these compounds were investigated by X-ray and neutron diffraction, X-ray photoelectron spectroscopy (XPS), and high-performance liquid chromatography (HPLC). The ac impedance measurements indicate a significant improvement of ionic conductivity as the result of incorporation of nitrogen into the structure. In the case of polycrystalline Li{sub 2.88}PO{sub 3.73}N{sub… more

Date: November 1, 1994

Creator: Wang, B.; Bates, J.B.; Chakoumakos, B.C.; Sales, B.C.; Kwak, B.S.; Zuhr, R.A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Carbon implanted in optical grade fused silica: annealing effects in reducing and oxidizing atmospheres

Carbon is implanted into fused silica with doses of 1, 3, 6, 10X10{sup 16} ions/cm{sup 2}. Infrared spectroscopy identified the formation of CO and CO{sub 2} molecules in the implanted glasses. Relations among concentrations of carbon dioxide, carbon monoxide, and carbon doses are established by the infrared measurements. Annealing under different atmospheres have dramatic effects on CO and CO{sub 2} concentrations.

Date: January 1, 1997

Creator: Tsung, Y.S.; Mu, R.; Ueda, A.; Henderson, D.O.; Wang, P.W.; White, C.W. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Vibrational and electronic transition in InAs quantum dots formed by sequential implantation of In and As in a-SiO[sub 2]

Optical, structural, and thermodynamic properties of materials can be changed by reducing their dimensions. We sequentially implanted In and As into fused silica windows in order to investigate formation and properties of InAs nano-particles. UV/VIS/NIR, FTIR in mid-IR, and far-IR spectroscopy were used to study change in electronic transitions and in vibrational modes (phonons) of the nano-particles InAs. The phonons can be confined to the surface of nano-particles and have frequencies falling… more

Date: January 1, 1996

Creator: Ueda, A.; Henderson, D.O.; Mu, R.; Tung, Y.S.; Hall, C.; Zhu, J.G. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

CdS Nanocrystals Formed in SiO{sub 2} Substrates by Ion Implantation

No Description Available.

Date: May 30, 2000

Creator: Desnica, U.V.; Ivanda, M.; Gamulin, O.; Tonejc, A.M.; White, C.W.; Sonder, E. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Optical and magnetic properties of silica implanted with N{sup +} and Fe{sup +}

Silica platelets (Corning 7940) were implanted sequentially with N{sup +} at 52 keV to different doses ranging from 0 to 1.2{times}10{sup 17} ions cm{sup {minus}2} and then with Fe{sup +} at 160 keV to a dose of 6{times}l0{sup 16} ions cm{sup {minus}2}. The optical absorption decreased with increasing N{sup +} dose at photon energies ranging from 1.4 to 6.5 eV. The relative intensity, S(0{degrees}), of the ferromagnetic resonance absorption and its resonance field, H{sub s}(0{degrees}), at {the… more

Date: December 1, 1995

Creator: Isobe, T.; Weeks, R.A. & Zuhr, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Sputter deposition and characterization of lithium cobalt oxide thin films and their applications in thin-film rechargeable lithium batteries

Li Co oxide thin films were deposited by rf magnetron sputtering of a LiCoO{sub 2} target in a 3:1 Ar/O{sub 2} mixture gas. From proton-induced gamma-ray emission analysis and Rutherford backscattering spectrometry, the average composition of these films was determined to be Li{sub 1.15}CoO{sub 2.16}. X-ray powder diffraction patterns of films annealed in air at 500-700 C were consistent with regular rhombohedral structure of crystalline LiCoO{sub 2}. Discharge curves of thin film lithium cells… more

Date: January 1, 1996

Creator: Wang, B.; Bates, J.B.; Luck, C.F.; Sales, B.C.; Zuhr, R.A. & Robertson, J.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Mesoscale Engineering of Nanocomposite Nonlinear Optical Materials

Complex nonlinear optical materials comprising elemental, compound or alloy quantum dots embedded in appropriate dielectric or semiconducting hosts may be suitable for deployment in photonic devices. Ion implantation, ion exchange followed by ion implantation, and pulsed laser deposition have ail been used to synthesize these materials. However, the correlation between the parameters of energetic-beam synthesis and the nonlinear optical properties is still very rudimentary when one starts to as… more

Date: November 1, 1999

Creator: Afonso, C.N.; Feldman, L.C.; Gonella, F.; Haglund, R.F.; Luepke, G.; Magruder, R.H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Laser induced diffusion of ion-implanted bismuth in fused silica

The near surface regions of optical grade fused silica discs (Spectrosil A) were modified by implantation with bismuth ions at 160 and 320 keV and at room temperature. The glasses implanted with a nominal dose of 6 {times} l0{sup 16} Bi{sup 2+} ions/cm{sup 2} were subsequently annealed with a 5 eV KrF pulsed excimer laser and by a furnace in oxygen atmosphere. Rutherford backscattering and optical absorption were measured before and after the anneals. Backscattering profiles after laser anneal … more

Date: December 31, 1994

Creator: Park, S.Y.; Weeks, R.A. & Zuhr, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department