Core-level spectroscopy of thin oxides and oxynitrides (open access)

Core-level spectroscopy of thin oxides and oxynitrides

Several spectroscopic methods are discussed that use core levels, such as photoelectron spectroscopy and absorption spectroscopy with photoelectron or fluorescence detection. Measurements are presented on the desorption of a chemical oxide and the growth of oxynitrides with N{sub 2}0 on Si(100). The stoichiometry is found to change strongly with thickness, from a nitrogen-terminated Si surface to a nearly-pure oxide in the outer region of 40--60 {Angstrom} films. Using a third generation synchrotron beam line a sensitivity of better than a tenth of a monolayer is achieved by a simple photocurrent measurement.
Date: July 19, 1994
Creator: Himpsel, F. J.; Akatsu, H. & Carlisle, J. A.
Object Type: Article
System: The UNT Digital Library
Development of a transient three-dimensional neutron transport code with feedback (open access)

Development of a transient three-dimensional neutron transport code with feedback

A new code is being developed at the Y-12 Plant for solving the time-dependent, three-dimensional Boltzmann transport model with feedback. The new code, PADK, uses the quasi-static method in its adiabatic form and is to be utilized to analyze hypothetical criticality accidents. A description of the code along with preliminary results without feedback are presented in this paper. The code is applied to 2 standard benchmark problems and the results are compared to another method. Also, the code is used to model the GODIVA reactor. Further work needed to be completed is described.
Date: July 19, 1994
Creator: Waddell, M.W. Jr.
Object Type: Article
System: The UNT Digital Library
Preparation of dielectrics HR mirrors from colloidal oxide suspensions containing organic polymer binders (open access)

Preparation of dielectrics HR mirrors from colloidal oxide suspensions containing organic polymer binders

Colloidal suspensions of oxides have been used to prepare dielectric HR (high reflective) mirrors, specifically for high power fusion case applications, on substrates up to 38 cm square using a meniscus coater. These coatings consist of porous quarterwave layers of alternating high and low refractive index oxides. Silica was used as the low index oxide and AlOOH, ZrO{sub 2}, or HfO{sub 2} as the high index material. Coatings were weak because of low particle-to-particle adhesion. Use of organic polymer binders in the high index component was found to increase strength, thereby improving the laser damage threshold and also reducing the number of layers required for 99% reflection due to increased refractive index.
Date: July 19, 1994
Creator: Thomas, I. M.
Object Type: Article
System: The UNT Digital Library
Program status 3. quarter -- FY 1994: Confinement systems programs (open access)

Program status 3. quarter -- FY 1994: Confinement systems programs

Highlights of the DIII-D Research Operations are: began experimental research operations; successfully passed radiative divertor project review; presented papers at PSI, Diagnostics, and EPS meetings and prepared IAEA synopses; new computer speeds up data acquisition; completed installation of FWCD antennas with Faraday shields; and completed report of radiative divertor preliminary design with review committee. Summaries are given for progress in research programs; operations; mechanical engineering; electrical engineering; upgrade project; operations support; and collaborative efforts. Brief summaries are given for progress on the International Cooperation task which include JET, ASDEX, TEXTOR, TORE SUPRA, JAERI, TRINTI, T-10, and ARIES support. The work in support of the development plan for the TPX (Tokamak Physics Experiment) goals and milestones continued. Progress in improving on existing models and codes leading to improved understanding of experiments is given. Highlights from the User Service Center are: 18 gigabytes of disks were purchased for exclusive fusion use; a Hewlett-Packard 9000 Series 800 T500 computer was selected as the fusion complete server; the first VAX was removed from the USC cluster; security vulnerability on HP VUE software was corrected; and a cleanup script was developed for the NERSC Cray system. A list of personnel and their assignments is given …
Date: July 19, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Program status 3. quarter -- FY 1994: ITER and technology (open access)

Program status 3. quarter -- FY 1994: ITER and technology

During this quarter all technical work and documentation of the PULSAR design was completed. They also assisted UCLA in the planning of the DEMO program.In the area of RF technology, a decision was made to fabricate 4in x 4in gyrotron distributed window. An finally, they obtained good agreement between code predictions and measured data for the up and down field redeposition of tungsten in the DIMES-8 experiment.
Date: July 19, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Static internal pressure capacity of Hanford Single-Shell Waste Tanks (open access)

Static internal pressure capacity of Hanford Single-Shell Waste Tanks

Underground single-shell waste storage tanks located at the Hanford Site in Richland, Washington, generate gaseous mixtures that could be ignited, challenging the structural integrity of the tanks. The structural capacity of the single-shell tanks to internal pressure is estimated through nonlinear finite-element structural analyses of the reinforced concrete tank. To determine their internal pressure capacity, designs for both the million-gallon and the half-million-gallon tank are evaluated on the basis of gross structural instability.
Date: July 19, 1994
Creator: Julyk, L. J.
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 19, Number 53, Pages 5557-5664, July 19, 1994 (open access)

Texas Register, Volume 19, Number 53, Pages 5557-5664, July 19, 1994

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: July 19, 1994
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Thermal effects on the STAR electromagnetic calorimeter (open access)

Thermal effects on the STAR electromagnetic calorimeter

The STAR detector for the RHIC colliding beam accelerator is under construction at Brookhaven National Laboratory. This detector will consist of a number of subsystems. These include a silicon vertex detector (SVT) for charged particle tracks near the interaction region, a time projection chamber (TPC) for charged particle tracking, an array of plastic scintillation counters (CTB) in a layer around the TPC for triggering on charged particles, a conventional solenoidal magnet, and some additional small triggering detectors along the beam-line. An electromagnetic calorimeter (EMC) is an upgrade to the ``baseline`` detector configuration above. The conventional magnet and numerous electronic channels for the SVT and TPC subsystems will generate a considerable amount of heat during the operation of STAR. However, it is possible that a chiller for the magnet cooling water will not be available during some of the early STAR runs. As a result, the average magnet temperature may vary considerably between winter and summer. This note summarizes calculations and measurements performed to evaluate the effects of an elevated magnet temperature on the performance of the electromagnetic calorimeter.
Date: July 19, 1994
Creator: Fornek, T.; Guarino, V.; Spinka, H. & Underwood, D.
Object Type: Report
System: The UNT Digital Library