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Absence of Rapid Proton Decay and Origin of Low-Energy Particlesand Yukawa Couplings

Description: In string theory, massless particles often originate from a symmetry breaking of a large gauge symmetry G to its subgroup H. The absence of dimension-4 proton decay in supersymmetric theories suggests that ({bar D},L) are different from {bar H}({bar 5}) in their origins. In this article, we consider a possibility that they come from different irreducible components in g/h. Requiring that all the Yukawa coupling constants of quarks and leptons be generated from the super Yang-Mills interactions … more
Date: January 1, 2006
Creator: Tatar, Radu & Watari, Taizan
open access

Advanced Combustion Systems for Next Generation Gas Turbines

Description: Next generation turbine power plants will require high efficiency gas turbines with higher pressure ratios and turbine inlet temperatures than currently available. These increases in gas turbine cycle conditions will tend to increase NOx emissions. As the desire for higher efficiency drives pressure ratios and turbine inlet temperatures ever higher, gas turbines equipped with both lean premixed combustors and selective catalytic reduction after treatment eventually will be unable to meet the ne… more
Date: January 1, 2006
Creator: Haynes, Joel; Janssen, Jonathan; Russell, Craig & Huffman, Marcus
open access

ALEGRA-HEDP validation strategy.

Description: This report presents a initial validation strategy for specific SNL pulsed power program applications of the ALEGRA-HEDP radiation-magnetohydrodynamics computer code. The strategy is written to be (1) broadened and deepened with future evolution of particular specifications given in this version; (2) broadly applicable to computational capabilities other than ALEGRA-HEDP directed at the same pulsed power applications. The content and applicability of the document are highly constrained by the R… more
Date: January 1, 2006
Creator: Garasi, Christopher Joseph; Mehlhorn, Thomas Alan & Trucano, Timothy Guy
open access

Algorithm and simulation development in support of response strategies for contamination events in air and water systems.

Description: Chemical/Biological/Radiological (CBR) contamination events pose a considerable threat to our nation's infrastructure, especially in large internal facilities, external flows, and water distribution systems. Because physical security can only be enforced to a limited degree, deployment of early warning systems is being considered. However to achieve reliable and efficient functionality, several complex questions must be answered: (1) where should sensors be placed, (2) how can sparse sensor inf… more
Date: January 1, 2006
Creator: Waanders, Bart Van Bloemen
open access

Analysis: Economic Impacts of Wind Applications in Rural Communities; June 18, 2004 -- January 31, 2005

Description: The purpose of this report is to compile completed studies on the economic impact of wind farms in rural communities and then to compare these studies. By summarizing the studies in an Excel spreadsheet, the raw data from a study is easily compared with the data from other studies. In this way, graphs can be made and conclusions drawn. Additionally, the creation of a database in which economic impact studies are summarized allows a greater understanding of the type of information gathered in an… more
Date: January 1, 2006
Creator: Pedden, M.
open access

Analysis of B → ωlν Decays With BaBar

Description: As part of the BaBar project at SLAC to study the properties of B mesons, we have carried out a study of the exclusive charmless semileptonic decay mode B → ωlν, which can be used to determine the magnitude of the Cabbibo- Kobayashi-Maskawa matrix element Vub. Using simulated event samples, this study focuses on determining criteria on variables for selection of B → ωlν signal and suppression of background from other types of BB events and continuum processes. In addition, we determine optimal … more
Date: January 1, 2006
Creator: Chu, Yiwen; Littlejohn, Bryce & Binfelder, J.
open access

An analysis of the causes of failure in high chrome oxide refractory materials from slagging gasifiers

Description: High Cr2O3 refractory materials are used to line the hot face of slagging gasifiers. Gasifiers are reaction chambers that convert water, oxygen, and a carbon feedstock into CO, H2, and methane at temperatures as high as 1575DGC and pressures up to 1000 psi. Ash in the carbon feedstock liquefies, erodes and corrodes the gasifier's refractory liner, contributing to liner failure within a few months to two years. The failure of a refractory liner decreases a gasifier's on-line availability and cau… more
Date: January 1, 2006
Creator: Bennett, James P.; Kwong, Kyei-Sing; Powell, Cynthia A.; Thomas, Hugh & Krabbe, Rick
open access

Analysis of the Habitat of Henslow's Sparrows and Grasshopper Sparrows Compared to Random Grassland Areas

Description: ABSTRAC T Henslow’s Sparrows are endangered prairie birds, and Grasshopper Sparrows are considered rare prairie birds. Both of these birds were abundant in Illinois, but their populations have been declining due to loss of the grasslands. This begins an ongoing study of the birds’ habitat so Fermilab can develop a land management plan for the Henslow’s and Grasshoppers. The Henslow’s were found at ten sites and Grasshoppers at eight sites. Once the birds were located, the vegetation at their si… more
Date: January 1, 2006
Creator: Maier, K.; Walton, R. & Kasper, P.
open access

Analytic and computational micromechanics of clustering and interphase effects in carbon nanotube composites.

Description: Effective elastic properties for carbon nanotube reinforced composites are obtained through a variety of micromechanics techniques. Using the in-plane elastic properties of graphene, the effective properties of carbon nanotubes are calculated utilizing a composite cylinders micromechanics technique as a first step in a two-step process. These effective properties are then used in the self-consistent and Mori-Tanaka methods to obtain effective elastic properties of composites consisting of align… more
Date: January 1, 2006
Creator: Seidel, Gary D.; Hammerand, Daniel Carl & Lagoudas, Dimitris C. (Texas A&M University, College Station, TX)
open access

Applicability of Related Data, Algorithms, and Models to the Simulation of Ground-Coupled Residential Hot Water Piping in California

Description: Residential water heating is an important consideration in California?s building energy efficiency standard. Explicit treatment of ground-coupled hot water piping is one of several planned improvements to the standard. The properties of water, piping, insulation, backfill materials, concrete slabs, and soil, their interactions, and their variations with temperature and over time are important considerations in the required supporting analysis. Heat transfer algorithms and models devised for gen… more
Date: January 1, 2006
Creator: Warner, J. L. & Lutz, J. D.
open access

Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration

Description: The Nature Conservancy is participating in a Cooperative Agreement with the Department of Energy (DOE) National Energy Technology Laboratory (NETL) to explore the compatibility of carbon sequestration in terrestrial ecosystems and the conservation of biodiversity. The title of the research project is ''Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration''. The objectives of the project are to: (1) improve carbon offset estimates produced in … more
Date: January 1, 2006
Creator: Stanley, Bill; Gonzalez, Patrick; Brown, Sandra; Henman, Jenny; Kant, Zoe; Murdock, Sarah Woodhouse et al.
open access

Application of Hydrogen Assisted Lean Operation to Natural Gas-Fueled Reciprocating Engines (HALO)

Description: Two key challenges facing Natural Gas Engines used for cogeneration purposes are spark plug life and high NOx emissions. Using Hydrogen Assisted Lean Operation (HALO), these two keys issues are simultaneously addressed. HALO operation, as demonstrated in this project, allows stable engine operation to be achieved at ultra-lean (relative air/fuel ratios of 2) conditions, which virtually eliminates NOx production. NOx values of 10 ppm (0.07 g/bhp-hr NO) for 8% (LHV H2/LHV CH4) supplementation at … more
Date: January 1, 2006
Creator: Smutzer, Chad
open access

Assessment of the potential for karst in the Rustler Formation at the WIPP site.

Description: This report is an independent assessment of the potential for karst dissolution in evaporitic strata of the Rustler Formation at the Waste Isolation Pilot Plant (WIPP) site. Review of the available data suggests that the Rustler strata thicken and thin across the area in depositional patterns related to lateral variations in sedimentary accommodation space and normal facies changes. Most of the evidence that has been offered for the presence of karst in the subsurface has been used out of conte… more
Date: January 1, 2006
Creator: Lorenz, John Clay
open access

Atomic scale investigations of the thermal and electron induced chemistry of small molecules on platinum(111) as revealed by scanning tunneling microscopy

Description: The work presented here can be divided into two parts: 1) an experimental and analysis section dealing with the investigation of small molecules such as methyl bromide, carbon dioxide, diatomic nitrogen, methane and methane?s photochemical derivative methyl radical adsorbed onto the Pt(111) surface, and 2) A detailed explanation of the current STM and chamber, with included designs and detailed instructions for operation and maintenance of both the STM and chamber. The investigations of the met… more
Date: January 1, 2006
Creator: Schwendemann, Todd Charles
open access

A Bayesian method for characterizing distributed micro-releases: II. inference under model uncertainty with short time-series data.

Description: Terrorist attacks using an aerosolized pathogen preparation have gained credibility as a national security concern after the anthrax attacks of 2001. The ability to characterize such attacks, i.e., to estimate the number of people infected, the time of infection, and the average dose received, is important when planning a medical response. We address this question of characterization by formulating a Bayesian inverse problem predicated on a short time-series of diagnosed patients exhibiting sym… more
Date: January 1, 2006
Creator: Marzouk, Youssef; Fast P. (Lawrence Livermore National Laboratory, Livermore, CA); Kraus, M. (Peterson AFB, CO) & Ray, J. P.
open access

Beam Energy Scaling on Ion-Induced Electron Yield from K+ Impacton Stainless Steel

Description: Electron clouds limit the performance of many major accelerators. Significant quantities of electrons result when halo ions are lost to beam tubes, generating gas which can be ionized and ion-induced electrons that can multiply and accumulate, causing degradation or loss of the ion beam. In order to understand the physical mechanisms of ion-induced electron production, experiments studied the impact of 50 to 400 keV K{sup +} ions on stainless steel surfaces near grazing incidence, using the 500… more
Date: January 1, 2006
Creator: Kireeff Covo, Michel; Molvik, Arthur; Friedman, Alex; Westenskow,Glen; Barnard, John J.; Cohen, Ronald et al.
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