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Experimental Demonstration of Guiding and Bending of Electromagnetic Waves in a Photonic Crystal

Description: The routing and interconnection of optical signals through narrow channels and around sharp corners is important for large-scale all-optical circuit applications. A recent computational result suggests that photonic crystals may offer a novel way of achieving this goal by providing a mechanism for guiding light that is fundamentally different from traditional index guiding. Waveguiding in a photonic crystal, and near 100% transmission of electromagnetic waves around sharp 90o corners were observed experimentally. Bend- ing radii were made smaller than one wavelength.
Date: October 15, 1998
Creator: Chow, E.; Hietala, .; Joannopoulos, J.D.; Lin, S. & Villeneuve, P.R.
Partner: UNT Libraries Government Documents Department

Overview of the Target Systems for the Spallation Neutron Source

Description: The technologies that are being utilized to design and build the target systems for a state-of-the-art accelerator- based neutron source, the Spallation Neutron Source (SNS), are discussed. Emphasis is given to the technology issues that present the greatest challenges. The present facility configuration, ongoing analysis, and planned research and development program are also described.
Date: October 15, 1998
Creator: Gabriel, T.A.; Haines, J.R. & McManamy, T.J.
Partner: UNT Libraries Government Documents Department

Dynamic Fiber Optic Sensors Under Intense Radioactive Environments

Description: A liquid mercury target will be used as the neutron source for the proposed Spallation Neutron Source facility. This target is subjected to bombardment by short-pulse, high-energy proton beams. The intense thermal loads caused by interaction of the pulsed proton beam with the mercury create an enormous rate of temperature rise ({approximately}10{sup 7} K/s) during a very brief beam pulse ({approximately } 0.5 {micro}s). The resulting pressure waves in the mercury will interact with the walls of the mercury target and may lead to large stresses. To gain confidence in the mercury target design concept and to benchmark the computer design codes, we tested various electrical and optical sensors for measuring the transient strains on the walls of a mercury container and the pressures in the mercury. The sensors were attached on several sample mercury targets that were tested at various beam facilities: Oak Ridge Electron Linear Accelerator, Los Alamos Neutron Science Center-Weapons Neutron Research, and Brookhaven National Laboratory's Alternating Gradient Synchrotron. The effects of intense background radiation on measured signals for each sensor are described and discussed. Preliminary results of limited tests at these facilities indicate that the fiber optic sensors function well in this intense radiation environment, whereas conventional electrical sensors are dysfunctional.
Date: October 15, 1998
Creator: Allison, S.W.; Earl, D.D.; Haines, J.R. & Tsai, C.C.
Partner: UNT Libraries Government Documents Department

Proton Decay Studies of the Light Lu, Tm and Ho Isotopes

Description: A double-sided Si-strip detector system has been installed and commissioned at the focal plane of the Recoil Mass Spectrometer at the Holifield Radioactive Ion Beam Facility. The system can be used for heavy charged particle emission studies with half-lives as low as a few {micro}sec. In this paper the authors present identification and study of the decay properties of the five new proton emitters: {sup 140}Ho, {sup 141m}Ho, {sup 145}Tm, {sup 150m}Lu and {sup 151m}Lu.
Date: October 15, 1998
Creator: Akovali, Y.; Batchelder, J.C.; Bingham, C.R.; Davinson, T.; Ginter, T.N.; Gross, C.J. et al.
Partner: UNT Libraries Government Documents Department

The MINOS long-baseline experiment at Fermilab.

Description: The MINOS long-baseline experiment will search for neutrino oscillations by measuring an intense {nu}{sub {mu}} beam at the end of a 730 km flight path. The 10,000 ton MINOS far detector will utilize magnetized steel plates interleaved with track chambers to reconstruct event topologies and to measure the energies of the muons, hadrons and electromagnetic showers produced by neutrino interactions. The experiment is designed to detect {nu}{sub {mu}} {r_arrow} {nu}{sub {tau}} and {nu}{sub {mu}} {r_arrow} {nu}{sub e} oscillations with {Delta}m{sup 2} {ge} 0.001 eV{sup 2} and sin{sup 2}(2{theta}) {ge} 0.01. Any oscillation signal observed can be verified and studied by several independent tests: a near/far rate comparison, the NC/CC event ratio, the CC and NC event energy spectra, and the identification of electrons and {tau} leptons. The neutrino beam can be operated in both wide-band and narrow-band configurations, allowing the detailed study oscillation phenomena. The experiment is scheduled to begin operation in 2001.
Date: October 15, 1997
Creator: Ayres, D. S.
Partner: UNT Libraries Government Documents Department

CO{sub 2} Huff-n-Puff process in a light oil shallow shelf carbonate reservoir. Quarterly technical progress report, July--September, 1995

Description: The principal objective of the Central Vacuum Unit (CVU) CO{sub 2} Huff-n-Puff (H-n-P) project is to determine the feasibility and practicality of the technology in a waterflooded shallow shelf carbonate environment. The results of parametric simulation of the CO{sub 2} H-n-P process, coupled with the CVU reservoir characterization components will determine if this process is technically and economically feasible for field implementation. The technology transfer objective of the project is to disseminate the knowledge gained through an innovative plan in support of the Department of Energy`s (DOE) objective of increasing domestic oil production and deferring the abandonment of shallow shelf carbonate (SSC) reservoirs. Tasks associated with this objective are carried out in what is considered a timely effort for near-term goals.
Date: October 15, 1995
Creator: Cole, R.; Prieditis, J. & Vogt, J. Wehner, S.
Partner: UNT Libraries Government Documents Department

Use of Dissolved and Colloidal Actinide Parameters within the 1996 Waste Isolation Pilot Plant Compliance Certification Application

Description: Many of the papers in this volume present detailed descriptions of the chemical analyses and methodologies that have been used to evaluate the maximum dissolved and colloid concentrations of actinides within the WIPP repository as part of the performance assessment. This paper describes the program fcm collecting experimental data and provides an overview of how the PA modeled the release of radionuclides to the accessible environment, and how volubility and colloid parameters were used by the PA models.
Date: October 15, 1998
Creator: Moore, R.C. & Stockman, C.T.
Partner: UNT Libraries Government Documents Department

Native Americans and Yucca Mountain: A revised and updated summary report on research undertaken between 1987 and 1991; Volume 2

Description: This report consists of Yucca Mountain Project bibliographies. It is the appendix to a report that summarizes data collected between September 1986 and September 1988 relative to Native American concerns involving the potential siting of a high-level nuclear waste repository at Yucca Mountain, Nevada. The data were collected from Western Shoshone and Southern Paiute people upon whose aboriginal lands the repository potentially is to be located. Western Shoshone people involved in the study were those resident or affiliated with reservation communities at Yomba and Duckwater, Nevada, and Death Valley, California. Southern Paiute people were at reservation communities at Moapa and Las Vegas. Additional persons of Western Shoshone and Southern Paiute descent were interviewed at Beatty, Tonopah, Caliente, Pahrump, and Las Vegas, Nevada. The work was part of a larger project of socioeconomic studies for the State of Nevada`s Nuclear Waste Projects office, conducted by Mountain West of Phoenix, Arizona.
Date: October 15, 1991
Creator: Fowler, C.S.
Partner: UNT Libraries Government Documents Department

The 2009 Influenza Pandemic: An Overview

Description: This report first provides a synopsis of key events, actions taken, and authorities invoked by World Health Organization (WHO), the U.S. federal government, and state and local governments.
Date: October 15, 2009
Creator: Lister, Sarah A. & Redhead, C. Stephen
Partner: UNT Libraries Government Documents Department

Afghanistan and Pakistan Reconstruction Opportunity Zones (ROZs), H.R. 1318/H.R. 1886/H.R. 2410 and S. 496: Issues and Arguments

Description: This report discusses proposed legislation that would establish a unilateral U.S. trade preference program for Afghanistan and parts of Pakistan. The legislation would permit certain goods produced in designated geographic areas called Reconstruction Opportunity Zones (ROZs) to be imported into the United States duty-free.
Date: October 15, 2009
Creator: Bolle, Mary Jane
Partner: UNT Libraries Government Documents Department

Synthesis report on thermally driven coupled processes

Description: The main purpose of this report is to document observations and data on thermally coupled processes for conditions that are expected to occur within and around a repository at Yucca Mountain. Some attempt is made to summarize values of properties (e.g., thermal properties, hydrologic properties) that can be measured in the laboratory on intact samples of the rock matrix. Variation of these properties with temperature, or with conditions likely to be encountered at elevated temperature in the host rock, is of particular interest. However, the main emphasis of this report is on direct observation of thermally coupled processes at various scales. Direct phenomenological observations are vitally important in developing and testing conceptual models. If the mathematical implementation of a conceptual model predicts a consequence that is not observed, either (1) the parameters or the boundary conditions used in the calculation are incorrect or (2) the conceptual basis of the model does not fit the experiment; in either case, the model must be revised. For example, the effective continuum model that has been used in thermohydrology studies combines matrix and fracture flow in a way that is equivalent to an assumption that water is imbibed instantaneously from fractures into adjacent, partially saturated matrix. Based on this approximation, the continuum-flow response that is analogous to fracture flow will not occur until the effective continuum is almost completely saturated. This approximation is not entirely consistent with some of the experimental data presented in this report. This report documents laboratory work and field studies undertaken in FY96 and FY97 to investigate thermally coupled processes such as heat pipes and fracture-matrix coupling. In addition, relevant activities from past years, and work undertaken outside the Yucca Mountain project are summarized and discussed. Natural and artificial analogs are also discussed to provide a convenient source of material ...
Date: October 15, 1997
Creator: Hardin, E.L.
Partner: UNT Libraries Government Documents Department

Native Americans and Yucca Mountain: A revised and updated summary report on research undertaken between 1987 and 1991; Volume 1

Description: This report summarizes data collected between September 1986 and September 1988 relative to Native American concerns involving the potential siting of a high-level nuclear waste repository at Yucca Mountain, Nevada. The data were collected from Western Shoshone and Southern Paiute people upon whose aboriginal lands the repository potentially is to be located. Western Shoshone people involved in the study were those resident or affiliated with reservation communities at Yomba and Duckwater, Nevada, and Death Valley, California. Southern Paiute people were at reservation communities at Moapa and Las Vegas. Additional persons of Western Shoshone and Southern Paiute descent were interviewed at Beatty, Tonopah, Caliente, Pahrump, and Las Vegas, Nevada. The work was part of a larger project of socioeconomic studies for the State of Nevada`s Nuclear Waste Projects office, conducted by Mountain West of Phoenix, Arizona.
Date: October 15, 1991
Creator: Fowler, C.S.
Partner: UNT Libraries Government Documents Department

Improved Efficiency of Miscible CO2 Floods and Enhanced Prospects for CO2 Flooding Heterogeneous Reservoirs

Description: The goal of this project is to improve the efficiency of miscible CO2 floods and enhance the prospects for flooding heterogeneous reservoirs. This report provides results of the second year of the three-year project that will be exploring three principles: (1) Fluid and matrix interactions (understanding the problems). (2) Conformance control/sweep efficiency (solving the problems. 3) Reservoir simulation for improved oil recovery (predicting results).
Date: October 15, 1999
Creator: Grigg, Reid B. & Schechter, David S.
Partner: UNT Libraries Government Documents Department

The 2009 Influenza Pandemic: An Overview

Description: This report describes the World Health Organization (WHO) process to determine the phase of a threatened or emerging flu pandemic, and touches on several related issues.
Date: October 15, 2009
Creator: Lister, Sarah A. & Redhead, C. Stephen
Partner: UNT Libraries Government Documents Department

Greece Update

Description: This report discusses current issues regarding Greece's recent elections, economy, and foreign policies.
Date: October 15, 2009
Creator: Migdalovitz, Carol
Partner: UNT Libraries Government Documents Department

Low-(18)O Silicic Magmas: Why Are They So Rare?

Description: LOW-180 silicic magmas are reported from only a small number of localities (e.g., Yellowstone and Iceland), yet petrologic evidence points to upper crustal assimilation coupled with fractional crystallization (AFC) during magma genesis for nearly all silicic magmas. The rarity of 10W-l `O magmas in intracontinental caldera settings is remarkable given the evidence of intense 10W-l*O meteoric hydrothermal alteration in the subvolcanic remnants of larger caldera systems. In the Platoro caldera complex, regional ignimbrites (150-1000 km3) have plagioclase 6180 values of 6.8 + 0.1%., whereas the Middle Tuff, a small-volume (est. 50-100 km3) post-caldera collapse pyroclastic sequence, has plagioclase 8]80 values between 5.5 and 6.8%o. On average, the plagioclase phenocrysts from the Middle Tuff are depleted by only 0.3%0 relative to those in the regional tuffs. At Yellowstone, small-volume post-caldera collapse intracaldera rhyolites are up to 5.5%o depleted relative to the regional ignimbrites. Two important differences between the Middle Tuff and the Yellowstone 10W-180 rhyolites elucidate the problem. Middle Tuff magmas reached water saturation and erupted explosively, whereas most of the 10W-l 80 Yellowstone rhyolites erupted effusively as domes or flows, and are nearly devoid of hydrous phenocrysts. Comparing the two eruptive types indicates that assimilation of 10W-180 material, combined with fractional crystallization, drives silicic melts to water oversaturation. Water saturated magmas either erupt explosively or quench as subsurface porphyrins bejiire the magmatic 180 can be dramatically lowered. Partial melting of low- 180 subvolcanic rocks by near-anhydrous magmas at Yellowstone produced small- volume, 10W-180 magmas directly, thereby circumventing the water saturation barrier encountered through normal AFC processes.
Date: October 15, 1998
Creator: Balsley, S.D. & Gregory, R.T.
Partner: UNT Libraries Government Documents Department

Defect and dopant diffusion in ion implanted silcon: an atomic scale simulation approach

Description: We present an atomistic approach to the development of predictive process simulation tools. First principles methods are used to construct a database of defect and dopant energetics. This is used as input for kinetic Monte Carlo simulations of ion implantation and dopant diffusion under a wide variety of technologically relevant conditions. Our simulations are in excellent agreement with annealing experiments on 20-80 keV B implants into Si, and with those on 50 keV Si implants into complex B-doped structures. Our calculations produce novel predictions of the time evolution of the electrically active B fraction during annealing.
Date: October 15, 1998
Creator: Carturla, M J; Diaz de la Rubia, T; Lenosky, T J & Theiss, S K
Partner: UNT Libraries Government Documents Department

Eddy-current-induced multipole field calculations.

Description: Time-varying magnetic fields of magnets in booster accelerators induce substantial eddy currents in the vacuum chambers. The eddy currents in turn act to produce various multipole fields that act on the beam. These fields must be taken into account when doing a lattice design. In the APS booster, the relatively long dipole magnets (3 meters) are linearly ramped to accelerate the injected 325 MeV beam to 7 GeV. Substantial dipole and sextupole fields are generated in the elliptical vacuum chamber from the induced eddy currents. In this note, formulas for the induced dipole and sextupole fields are derived for elliptical and rectangular vacuum chambers for a time-varying dipole field. A discussion is given on how to generalize this derivation method to include eddy-current-induced multipole fields from higher multipole magnets (quadrupole, sextupole, etc.). Finally, transient effects are considered.
Date: October 15, 2003
Creator: Sereno, N. S. & Kim, S. H.
Partner: UNT Libraries Government Documents Department

Determination of the Rate of Formation of Hydroceramic Waste Forms made with INEEL Calcined Wastes

Description: The formulation, synthesis, characterization and hydration kinetics of hydroceramic waste forms designed as potential hosts for existing INEEL calcine high-level wastes have been established as functions of temperature and processing time. Initial experimentations were conducted with several aluminosilicate pozzolanic materials, ranging from fly ash obtained from various power generating coal and other combustion industries to reactive alumina, natural clays and ground bottled glass powders. The final selection criteria were based on the ease of processing, excellent physical properties and chemical durability (low-leaching) determined from the PCT test produced in hydroceramic. The formulation contains vermiculite, Sr(NO32), CsC1, NaOH, thermally altered (calcined natural clay) and INEEL simulated calcine high-level nuclear wastes and 30 weight percent of fluorinel blend calcine and zirconia calcine. Syntheses were carried out at 75-200 degree C at autogeneous water pressure (100% relative humidity) at various time intervals. The resulting monolithic compact products were hard and resisted breaking when dropped from a 5 ft height. Hydroceramic host mixed with fluorinel blend calcine and processed at 75 degree C crumbled into rice hull-side grains or developed scaly flakes. However, the samples equally possessed the same chemical durability as their unbroken counterparts. Phase identification by XRD revealed that hydroceramic host crystallized type zeolite at 75-150 degree C and NaP1 at 175-200 degree C in addition to the presence of quartz phase originating from the clay reactant. Hydroceramic host mixed with either fluorinel blend calcine or zirconia calcine crystallized type A zeolite at 75-95 degree C, formed a mixture of type A zeolite and hydroxysodalite at 125-150 degree C and hydroxysodalite at 175-200 degree C. Quartz, calcium fluoride and zirconia phases from the clay reactant and the two calcine wastes were also detected. The PCT test solution conductivity, pH and analytical concentration measured as a function of time decrease exponentially. In some ...
Date: October 15, 2001
Creator: Scheetz, Barry & Olanrewaju, Johnson
Partner: UNT Libraries Government Documents Department

E-Area Performance Assessment Interim Measures Assessment FY2003

Description: Projected impacts on disposal limits of various studies have been estimated. Interim measures to compensate for the impacts are needed for the Engineered Trench and the Intermediate Level Vault. Interim measures are due to projected decreases in the radionuclide disposal limits derived from the groundwater pathway as a result of the Aquifer Source Node study and consideration of potential artificial dilution caused by the large size of the grid elements in the Intermediate Level Vault groundwater model. Recently, it became evident that, in the development of the groundwater model for the Slit Trenches, the selection of aquifer source nodes (i.e., the spatial elements of the saturated zone model into which the flux of radionuclides from the unsaturated zone model is introduced) was not optimum6. Optimizing the source nodes would likely result in increases in the resulting groundwater concentrations, which would suggest that the radionuclide disposal limits should be reduced. However, other studies may result in increases in disposal limits 7. Therefore, a decision was made to develop and implement an annual summary of the potential impact of technical studies and other information on radionuclide disposal limits and whether mitigating measures should be imposed pending completion and implementation of the studies. This report is the first such summary.
Date: October 15, 2003
Creator: Wilhite, E.L.
Partner: UNT Libraries Government Documents Department