Michigan Technological Center for Nanostructured and Lightweight Materials in the Department of Chemical Engineering (Phase II) (open access)

Michigan Technological Center for Nanostructured and Lightweight Materials in the Department of Chemical Engineering (Phase II)

Summaries of the followings tasks are given in this report: Task 1 - Lightweight, Thermally Conductive Bipolar Plates for Improved Thermal Management in Fuel Cells; Task 2 - Exploration of pseudomorphic nanoscale overlayer bimetallic catalysts; Task 3 - Hybrid inorganic/organic polymer nanocomposites; Task 4 - Carbonaceous Monolithic Electrodes for Fuel Cells and Rechargeable Batteries; and Task 5 - Movement and Freeze of Water in Fuel Cell Electrodes.
Date: December 10, 2009
Creator: Mullins, M.; Rogers, T.; King, J.; Holles, J.; Keith, J.; Heiden, P. et al.
Object Type: Report
System: The UNT Digital Library
SUMMARY REPORT DIRECT PUSH TECHNOLOGY BOREHOLES FOR GEOPHYSICAL LOGGING 200-IS-1 OPERABLE UNIT FY2008 (open access)

SUMMARY REPORT DIRECT PUSH TECHNOLOGY BOREHOLES FOR GEOPHYSICAL LOGGING 200-IS-1 OPERABLE UNIT FY2008

None
Date: February 10, 2009
Creator: AK, LEE
Object Type: Report
System: The UNT Digital Library
Uncertainty and Sensitivity of Contaminant Travel Times from the Upgradient Nevada Test Site to the Yucca Mountain Area (open access)

Uncertainty and Sensitivity of Contaminant Travel Times from the Upgradient Nevada Test Site to the Yucca Mountain Area

Yucca Mountain (YM), Nevada, has been proposed by the U.S. Department of Energy as the nation’s first permanent geologic repository for spent nuclear fuel and highlevel radioactive waste. In this study, the potential for groundwater advective pathways from underground nuclear testing areas on the Nevada Test Site (NTS) to intercept the subsurface of the proposed land withdrawal area for the repository is investigated. The timeframe for advective travel and its uncertainty for possible radionuclide movement along these flow pathways is estimated as a result of effective-porosity value uncertainty for the hydrogeologic units (HGUs) along the flow paths. Furthermore, sensitivity analysis is conducted to determine the most influential HGUs on the advective radionuclide travel times from the NTS to the YM area. Groundwater pathways are obtained using the particle tracking package MODPATH and flow results from the Death Valley regional groundwater flow system (DVRFS) model developed by the U.S. Geological Survey (USGS). Effectiveporosity values for HGUs along these pathways are one of several parameters that determine possible radionuclide travel times between the NTS and proposed YM withdrawal areas. Values and uncertainties of HGU porosities are quantified through evaluation of existing site effective-porosity data and expert professional judgment and are incorporated in …
Date: September 10, 2009
Creator: Zhu, J.; Pohlmann, K.; Chapman, J.; Russell, C.; Carroll, R.W.H. & Shafer, D.
Object Type: Report
System: The UNT Digital Library
Detailed Geophysical Fault Characterization in Yucca Flat, Nevada Test Site, Nevada (open access)

Detailed Geophysical Fault Characterization in Yucca Flat, Nevada Test Site, Nevada

Yucca Flat is a topographic and structural basin in the northeastern part of the Nevada Test Site (NTS) in Nye County, Nevada. Between the years 1951 and 1992, 659 underground nuclear tests took place in Yucca Flat; most were conducted in large, vertical excavations that penetrated alluvium and the underlying Cenozoic volcanic rocks. Radioactive and other potential chemical contaminants at the NTS are the subject of a long-term program of investigation and remediation by the U.S. Department of Energy (DOE), National Nuclear Security Administration, Nevada Site Office, under its Environmental Restoration Program. As part of the program, the DOE seeks to assess the extent of contamination and to evaluate the potential risks to humans and the environment from byproducts of weapons testing. To accomplish this objective, the DOE Environmental Restoration Program is constructing and calibrating a ground-water flow model to predict hydrologic flow in Yucca Flat as part of an effort to quantify the subsurface hydrology of the Nevada Test Site. A necessary part of calibrating and evaluating a model of the flow system is an understanding of the location and characteristics of faults that may influence ground-water flow. In addition, knowledge of fault-zone architecture and physical properties is a …
Date: February 10, 2009
Creator: Asch, Theodore H.; Sweetkind, Donald; Burton, Bethany L. & Wallin, Erin L.
Object Type: Report
System: The UNT Digital Library
Gordon Research Conference on Radiation & Climate in 2009, July 5 -10 (open access)

Gordon Research Conference on Radiation & Climate in 2009, July 5 -10

The 2009 Gordon Research Conference on Radiation and Climate will present cutting-edge research on the outstanding issues in global climate change with focus on the radiative forcing and sensitivity of the climate system and associated physical processes. The Conference will feature a wide range of topics, including grand challenges in radiation and climate, radiative forcing, climate feedbacks, cloud processes in climate system, hydrological cycle in changing climate, absorbing aerosols and Asian monsoon, recent climate changes, and geo-engineering. The invited speakers will present the recent most important advances and future challenges in these areas. The Conference will bring together a collection of leading investigators who are at the forefront of their field, and will provide opportunities for scientists especially junior scientists and graduate students to present their work in poster format and exchange ideas with leaders in the field. The collegial atmosphere of this Conference, with programmed discussion sessions as well as opportunities for informal gatherings in the afternoons and evenings, provides an avenue for scientists from different disciplines to brainstorm and promotes cross-disciplinary collaborations in the various research areas represented.
Date: July 10, 2009
Creator: Fu, Quiang
Object Type: Article
System: The UNT Digital Library
Me-3,2-HOPO Complexes of Near Infra-Red (NIR) Emitting Lanthanides: Efficient Sensitization of Yb(III) and Nd(III) in Aqueous Solution (open access)

Me-3,2-HOPO Complexes of Near Infra-Red (NIR) Emitting Lanthanides: Efficient Sensitization of Yb(III) and Nd(III) in Aqueous Solution

The synthesis, X-ray structure, solution stability, and photophysical properties of several trivalent lanthanide complexes of Yb(III) and Nd(III) using both tetradentate and octadentate ligand design strategies and incorporating the 1-methyl-3-hydroxy-pyridin-2-one (Me-3,2-HOPO) chelate group are reported. Both the Yb(III) and Nd(III) complexes have emission bands in the Near Infra-Red (NIR) region, and this luminescence is retained in aqueous solution ({Phi}{sub tot}{sup Yb} {approx} 0.09-0.22%). Furthermore, the complexes demonstrate very high stability (pYb {approx} 18.8-21.9) in aqueous solution, making them good candidates for further development as probes for NIR imaging. Analysis of the low temperature (77 K) photophysical measurements for a model Gd(III) complex were used to gain an insight into the electronic structure, and were found to agree well with corresponding TD-DFT calculations at the B3LYP/6-311G{sup ++}(d,p) level of theory for a simplified model monovalent sodium complex.
Date: November 10, 2009
Creator: Moore, Evan G.; Xu, Jide; Dodani, Sheel; Jocher, Christoph; D'Aleo, Anthony; Seitz, Michael et al.
Object Type: Article
System: The UNT Digital Library
Escapement and Productivity of Spring Chinook Salmon and Summer Steelhead in the John Day River Basin, 2005-2006 Annual Technical Report. (open access)

Escapement and Productivity of Spring Chinook Salmon and Summer Steelhead in the John Day River Basin, 2005-2006 Annual Technical Report.

The objectives are: (1) Estimate number and distribution of spring Chinook salmon Oncorhynchus tshawytscha redds and spawners in the John Day River subbasin; and (2) Estimate smolt-to-adult survival rates (SAR) and out-migrant abundance for spring Chinook and summer steelhead O. mykiss and life history characteristics of summer steelhead. The John Day River subbasin supports one of the last remaining intact wild populations of spring Chinook salmon and summer steelhead in the Columbia River Basin. These populations, however, remain depressed relative to historic levels. Between the completion of the life history and natural escapement study in 1984 and the start of this project in 1998, spring Chinook spawning surveys did not provide adequate information to assess age structure, progeny-to-parent production values, smolt-to-adult survival (SAR), or natural spawning escapement. Further, only very limited information is available for steelhead life history, escapement, and productivity measures in the John Day subbasin. Numerous habitat protection and rehabilitation projects to improve salmonid freshwater production and survival have also been implemented in the basin and are in need of effectiveness monitoring. While our monitoring efforts outlined here will not specifically measure the effectiveness of any particular project, they will provide much needed background information for developing context …
Date: April 10, 2009
Creator: Schultz, Terra Lang; Wilson, Wayne H. & Ruzycki, James R.
Object Type: Report
System: The UNT Digital Library
Time-Based Data Streams: Fundamental Concepts for a Data Resource for Streams (open access)

Time-Based Data Streams: Fundamental Concepts for a Data Resource for Streams

Real time data, which we call data streams, are readings from instruments, environmental, bodily or building sensors that are generated at regular intervals and often, due to their volume, need to be processed in real time. Often a single pass is all that can be made on the data, and a decision to discard or keep the instance is made on the spot. Too, the stream is for all practical purposes indefinite, so decisions must be made on incomplete knowledge. This notion of data streams has a different set of issues from a file, for instance, that is byte streamed to a reader. The file is finite, so the byte stream is becomes a processing convenience more than a fundamentally different kind of data. Through the duration of the project we examined three aspects of streaming data: the first, techniques to handle streaming data in a distributed system organized as a collection of web services, the second, the notion of the dashboard and real time controllable analysis constructs in the context of the Fermi Tevatron Beam Position Monitor, and third and finally, we examined provenance collection of stream processing such as might occur as raw observational data flows from the …
Date: October 10, 2009
Creator: Plale, Beth A.
Object Type: Report
System: The UNT Digital Library
The Impact of IBM Cell Technology on the Programming Paradigm in the Context of Computer Systems for Climate and Weather Models (open access)

The Impact of IBM Cell Technology on the Programming Paradigm in the Context of Computer Systems for Climate and Weather Models

The call for ever-increasing model resolutions and physical processes in climate and weather models demands a continual increase in computing power. The IBM Cell processor's order-of-magnitude peak performance increase over conventional processors makes it very attractive to fulfill this requirement. However, the Cell's characteristics, 256KB local memory per SPE and the new low-level communication mechanism, make it very challenging to port an application. As a trial, we selected the solar radiation component of the NASA GEOS-5 climate model, which: (1) is representative of column physics components (half the total computational time), (2) has an extremely high computational intensity: the ratio of computational load to main memory transfers, and (3) exhibits embarrassingly parallel column computations. In this paper, we converted the baseline code (single-precision Fortran) to C and ported it to an IBM BladeCenter QS20. For performance, we manually SIMDize four independent columns and include several unrolling optimizations. Our results show that when compared with the baseline implementation running on one core of Intel's Xeon Woodcrest, Dempsey, and Itanium2, the Cell is approximately 8.8x, 11.6x, and 12.8x faster, respectively. Our preliminary analysis shows that the Cell can also accelerate the dynamics component (~;;25percent total computational time). We believe these dramatic performance …
Date: January 10, 2009
Creator: Zhou, Shujia; Duffy, Daniel; Clune, Thomas; Suarez, Max; Williams, Samuel & Halem, Milton
Object Type: Article
System: The UNT Digital Library
2008 Brookhaven National Laboratory Annual Illness and Injury Surveillance Report (open access)

2008 Brookhaven National Laboratory Annual Illness and Injury Surveillance Report

The U.S. Department of Energy’s (DOE) commitment to assuring the health and safety of its workers includes the conduct of epidemiologic surveillance activities that provide an early warning system for health problems among workers. The Illness and Injury Surveillance Program monitors illnesses and health conditions that result in an absence of workdays, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: December 10, 2009
Creator: United States. Department of Energy. Office of Illness and Injury Prevention Programs.
Object Type: Report
System: The UNT Digital Library
Final Technical Report: Genetic and Molecular Analysis of a new control pathway in assimilate partitioning. (open access)

Final Technical Report: Genetic and Molecular Analysis of a new control pathway in assimilate partitioning.

Assimilate partitioning refers to the systemic distribution of photoassimilate from sites of primary assimilation (source tissue) to import-dependent tissues and organs (sinks). One of the defining questions in this area is how plants balance source productivity with sink demand. We discovered a sucrose-sensing signal transduction pathway that controls the activity of BvSUT1, a proton-sucrose symporter in sugar beet leaf tissue. Sucrose symporters are responsible for sucrose accumulation in the phloem of many plants and, therefore, they mediate the pivotal step in the long-distance transport of photoassimilate to non-photosynthetic tissues, such as roots and seed. We previously showed that sucrose transport activity is directly proportional to the transcription rate of BvSUT1 and that symporter mRNA and protein have high rates of turnover with half-lives on the order of 2 h. We further demonstrated that symporter transcription is regulated by sucrose levels in the leaf and that sucrose-dependent regulation of BvSUT1 transcription is mediated, at least in part, by a protein phosphorylation relay pathway. The goal of the experiments during this current grant were to use genetic and molecular approaches to identify essential components of this vital regulatory system. The initial objectives were to: (1) to characterize Arabidopsis mutants we've isolated that …
Date: March 10, 2009
Creator: Bush, Daniel, R.
Object Type: Report
System: The UNT Digital Library
Interpretation of Wild 2 Dust Fine Structure: Comparison of Stardust Aluminium Foil Craters to the Three-Dimensional Shape of Experimental Impacts by Artificial Aggregate Particles and Meteorite Powders (open access)

Interpretation of Wild 2 Dust Fine Structure: Comparison of Stardust Aluminium Foil Craters to the Three-Dimensional Shape of Experimental Impacts by Artificial Aggregate Particles and Meteorite Powders

New experimental results show that Stardust crater morphology is consistent with interpretation of many larger Wild 2 dust grains being aggregates, albeit most of low porosity and therefore relatively high density. The majority of large Stardust grains (i.e. those carrying most of the cometary dust mass) probably had density of 2.4 g cm{sup -3} (similar to soda-lime glass used in earlier calibration experiments) or greater, and porosity of 25% or less, akin to consolidated carbonaceous chondrite meteorites, and much lower than the 80% suggested for fractal dust aggregates. Although better size calibration is required for interpretation of the very smallest impacting grains, we suggest that aggregates could have dense components dominated by {micro}m-scale and smaller sub-grains. If porosity of the Wild 2 nucleus is high, with similar bulk density to other comets, much of the pore-space may be at a scale of tens of micrometers, between coarser, denser grains. Successful demonstration of aggregate projectile impacts in the laboratory now opens the possibility of experiments to further constrain the conditions for creation of bulbous (Type C) tracks in aerogel, which we have observed in recent shots. We are also using mixed mineral aggregates to document differential survival of pristine composition and …
Date: December 10, 2009
Creator: Kearsley, A T; Burchell, M J; Price, M C; Graham, G A; Wozniakiewicz, P J; Cole, M J et al.
Object Type: Article
System: The UNT Digital Library
The Synthesis, Structures and Chemical Properties of Macrocyclic Ligands Covalently Bonded into Layered Arrays (open access)

The Synthesis, Structures and Chemical Properties of Macrocyclic Ligands Covalently Bonded into Layered Arrays

The overall goal of this project is to utilize mixed metal phosphonate phosphates for the separation of lanthanides as a group from actinides and further separate individual actinides.
Date: July 10, 2009
Creator: Clearfield, Abraham
Object Type: Report
System: The UNT Digital Library
Photoelectrochemistry of Semiconductor Nanowire Arrays (open access)

Photoelectrochemistry of Semiconductor Nanowire Arrays

This project supported research on the growth and photoelectrochemical characterization of semiconductor nanowire arrays, and on the development of catalytic materials for visible light water splitting to produce hydrogen and oxygen. Silicon nanowires were grown in the pores of anodic aluminum oxide films by the vapor-liquid-solid technique and were characterized electrochemically. Because adventitious doping from the membrane led to high dark currents, silicon nanowire arrays were then grown on silicon substrates. The dependence of the dark current and photovoltage on preparation techniques, wire diameter, and defect density was studied for both p-silicon and p-indium phosphide nanowire arrays. The open circuit photovoltage of liquid junction cells increased with increasing wire diameter, reaching 350 mV for micron-diameter silicon wires. Liquid junction and radial p-n junction solar cells were fabricated from silicon nano- and microwire arrays and tested. Iridium oxide cluster catalysts stabilized by bidentate malonate and succinate ligands were also made and studied for the water oxidation reaction. Highlights of this project included the first papers on silicon and indium phosphide nanowire solar cells, and a new procedure for making ligand-stabilized water oxidation catalysts that can be covalently linked to molecular photosensitizers or electrode surfaces.
Date: November 10, 2009
Creator: Mallouk, Thomas E & Redwing, Joan M
Object Type: Report
System: The UNT Digital Library
Some Properties of the M3D-C1 Form of the 3D Magnetohydrodynamics Equations (open access)

Some Properties of the M3D-C1 Form of the 3D Magnetohydrodynamics Equations

We introduce a set of scalar variables and projection operators for the vector momentum and magnetic field evolution equations that have several unique and desirable properties, making them a preferred system for solving the magnetohydrodynamics equations in a torus with a strong toroidal magnetic field. We derive a "weak form" of these equations that explicitly conserves energy and is suitable for a Galerkin finite element formulation provided the basis elements have C1 continuity. Systems of reduced equations are discussed, along with their energy conservation properties. An implicit time advance is presented that adds diagonally dominant self-adjoint energy terms to the mass matrix to obtain numerical stability.
Date: July 10, 2009
Creator: J. Breslau, N. Ferraro, S. Jardin
Object Type: Report
System: The UNT Digital Library
Sampling Artifacts from Conductive Silicone Tubing (open access)

Sampling Artifacts from Conductive Silicone Tubing

None
Date: April 10, 2009
Creator: Timko, Michael T.; Yu, Zhenhong; Kroll, Jesse; Jayne, John T.; Worsnop, Douglas R.; Liscinsky, David et al.
Object Type: Article
System: The UNT Digital Library
Pretreatment Engineering Platform (PEP) Integrated Test B Run Report--Caustic and Oxidative Leaching in UFP-VSL-T02A (open access)

Pretreatment Engineering Platform (PEP) Integrated Test B Run Report--Caustic and Oxidative Leaching in UFP-VSL-T02A

Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed and operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes” of the External Flowsheet Review Team (EFRT) issue response plan.( ) The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing.
Date: December 10, 2009
Creator: Geeting, John GH; Bredt, Ofelia P.; Burns, Carolyn A.; Golovich, Elizabeth C.; Guzman-Leong, Consuelo E.; Josephson, Gary B. et al.
Object Type: Report
System: The UNT Digital Library
CORRELATION BETWEEN RAINFALL PATTERNS AND THE WATER TABLE IN THEGENERAL SEPARATIONS AREA OF THE SAVANNAH RIVERSITE (open access)

CORRELATION BETWEEN RAINFALL PATTERNS AND THE WATER TABLE IN THEGENERAL SEPARATIONS AREA OF THE SAVANNAH RIVERSITE

The objective of the study was to evaluate rainfall and water table elevation data in search of a correlation that could be used to understand and predict water elevation changes. This information will be useful in placing screen zones for future monitoring wells and operations of groundwater treatment units. Fifteen wells in the General Separations Area (GSA) at Savannah River Site were evaluated from 1986 through 2001. The study revealed that the water table does respond to rainfall with minimal delay. (Water level information was available monthly, which restricted the ability to evaluate a shorter delay period.) Water elevations were found to be related to the cumulative sum (Q-Delta Sum) of the difference between the average rainfall for a specific month and the actual rainfall for that month, calculated from an arbitrary starting point. Water table elevations could also be correlated between wells, but using the right well for correlation was very important. The strongest correlation utilized a quadratic equation that takes into account the rainfall in a specific area and the rainfall from an adjacent area that contributes through a horizontal flow. Specific values vary from well to well as a result of geometry and underground variations. R2's for …
Date: August 10, 2009
Creator: Smith, C.
Object Type: Article
System: The UNT Digital Library
Feasibility of Recycling Plutonium and Minor Actinides in Light Water Reactors Using Hydride Fuel (open access)

Feasibility of Recycling Plutonium and Minor Actinides in Light Water Reactors Using Hydride Fuel

The objective of this DOE NERI program sponsored project was to assess the feasibility of improving the plutonium (Pu) and minor actinide (MA) recycling capabilities of pressurized water reactors (PWRs) by using hydride instead of oxide fuels. There are four general parts to this assessment: 1) Identifying promising hydride fuel assembly designs for recycling Pu and MAs in PWRs 2) Performing a comprehensive systems analysis that compares the fuel cycle characteristics of Pu and MA recycling in PWRs using the promising hydride fuel assembly designs identified in Part 1 versus using oxide fuel assembly designs 3) Conducting a safety analysis to assess the likelihood of licensing hydride fuel assembly designs 4) Assessing the compatibility of hydride fuel with cladding materials and water under typical PWR operating conditions Hydride fuel was found to offer promising transmutation characteristics and is recommended for further examination as a possible preferred option for recycling plutonium in PWRs.
Date: March 10, 2009
Creator: Greenspan, Ehud; Todreas, Neil & Taiwo, Temitope
Object Type: Report
System: The UNT Digital Library
Alliance for Computational Science Collaboration: HBCU Partnership at Alabama A&M University Continuing High Performance Computing Research and Education at AAMU (open access)

Alliance for Computational Science Collaboration: HBCU Partnership at Alabama A&M University Continuing High Performance Computing Research and Education at AAMU

This is the final report for the Department of Energy (DOE) project DE-FG02-06ER25746, entitled, "Continuing High Performance Computing Research and Education at AAMU". This three-year project was started in August 15, 2006, and it was ended in August 14, 2009. The objective of this project was to enhance high performance computing research and education capabilities at Alabama A&M University (AAMU), and to train African-American and other minority students and scientists in the computational science field for eventual employment with DOE. AAMU has successfully completed all the proposed research and educational tasks. Through the support of DOE, AAMU was able to provide opportunities to minority students through summer interns and DOE computational science scholarship program. In the past three years, AAMU (1). Supported three graduate research assistants in image processing for hypersonic shockwave control experiment and in computational science related area; (2). Recruited and provided full financial support for six AAMU undergraduate summer research interns to participate Research Alliance in Math and Science (RAMS) program at Oak Ridge National Lab (ORNL); (3). Awarded highly competitive 30 DOE High Performance Computing Scholarships ($1500 each) to qualified top AAMU undergraduate students in science and engineering majors; (4). Improved high performance computing laboratory at …
Date: November 10, 2009
Creator: Qian, Xiaoqing & Deng, Z. T.
Object Type: Report
System: The UNT Digital Library
ANOMALY STRUCTURE OF SUPERGRAVITY AND ANOMALY CANCELLATION (open access)

ANOMALY STRUCTURE OF SUPERGRAVITY AND ANOMALY CANCELLATION

We display the full anomaly structure of supergravity, including new D-term contributions to the conformal anomaly. This expression has the super-Weyl and chiral U(1){sub K} transformation properties that are required for implementation of the Green-Schwarz mechanism for anomaly cancellation. We outline the procedure for full anomaly cancellation. Our results have implications for effective supergravity theories from the weakly coupled heterotic string theory.
Date: June 10, 2009
Creator: Butter, Daniel & Gaillard, Mary K.
Object Type: Article
System: The UNT Digital Library
Performance Analysis of Mechanical Draft Cooling Tower (open access)

Performance Analysis of Mechanical Draft Cooling Tower

Industrial processes use mechanical draft cooling towers (MDCT's) to dissipate waste heat by transferring heat from water to air via evaporative cooling, which causes air humidification. The Savannah River Site (SRS) has cross-flow and counter-current MDCT's consisting of four independent compartments called cells. Each cell has its own fan to help maximize heat transfer between ambient air and circulated water. The primary objective of the work is to simulate the cooling tower performance for the counter-current cooling tower and to conduct a parametric study under different fan speeds and ambient air conditions. The Savannah River National Laboratory (SRNL) developed a computational fluid dynamics (CFD) model and performed the benchmarking analysis against the integral measurement results to accomplish the objective. The model uses three-dimensional steady-state momentum, continuity equations, air-vapor species balance equation, and two-equation turbulence as the basic governing equations. It was assumed that vapor phase is always transported by the continuous air phase with no slip velocity. In this case, water droplet component was considered as discrete phase for the interfacial heat and mass transfer via Lagrangian approach. Thus, the air-vapor mixture model with discrete water droplet phase is used for the analysis. A series of parametric calculations was performed …
Date: February 10, 2009
Creator: Lee, S.; Alfred Garrett, A.; James02 Bollinger, J. & Larry Koffman, L.
Object Type: Article
System: The UNT Digital Library
Chemical Effect of Dry and Wet Cleaning of the Ru Protective Layer of the Extreme ultraviolet (EUV) Lithography Reflector (open access)

Chemical Effect of Dry and Wet Cleaning of the Ru Protective Layer of the Extreme ultraviolet (EUV) Lithography Reflector

The authors report the chemical influence of cleaning of the Ru capping layer on the extreme ultraviolet (EUV) reflector surface. The cleaning of EUV reflector to remove the contamination particles has two requirements: to prevent corrosion and etching of the reflector surface and to maintain the reflectivity functionality of the reflector after the corrosive cleaning processes. Two main approaches for EUV reflector cleaning, wet chemical treatments [sulfuric acid and hydrogen peroxide mixture (SPM), ozonated water, and ozonated hydrogen peroxide] and dry cleaning (oxygen plasma and UV/ozone treatment), were tested. The changes in surface morphology and roughness were characterized using scanning electron microscopy and atomic force microscopy, while the surface etching and change of oxidation states were probed with x-ray photoelectron spectroscopy. Significant surface oxidation of the Ru capping layer was observed after oxygen plasma and UV/ozone treatment, while the oxidation is unnoticeable after SPM treatment. Based on these surface studies, the authors found that SPM treatment exhibits the minimal corrosive interactions with Ru capping layer. They address the molecular mechanism of corrosive gas and liquid-phase chemical interaction with the surface of Ru capping layer on the EUV reflector.
Date: April 10, 2009
Creator: Belau, Leonid; Park, Jeong Y.; Liang, Ted; Seo, Hyungtak & Somorjai, Gabor A.
Object Type: Article
System: The UNT Digital Library
Analysis of major trends in U.S. commercial trucking, 1977-2002. (open access)

Analysis of major trends in U.S. commercial trucking, 1977-2002.

This report focuses on various major long-range (1977-2002) and intermediate-range (1982-2002) U.S. commercial trucking trends. The primary sources of data for this period were the U.S. Bureau of the Census Vehicle Inventory and Use Survey and Truck Inventory and Use Survey. In addition, selected 1977-2002 data from the U.S. Department of Energy/Energy Information Administration and from the U.S. Department of Transportation/Federal Highway Administration's Highway Statistics were used. The report analyzes (1) overall gasoline and diesel fuel consumption patterns by passenger vehicles and trucks and (2) the population changes and fuels used by all commercial truck classes by selected truck type (single unit or combination), during specified time periods, with cargo-hauling commercial trucks given special emphasis. It also assesses trends in selected vehicle miles traveled, gallons per vehicle miles traveled, and gallons per cargo ton-mile traveled, as well as the effect of cargo tons per truck on fuel consumption. In addition, the report examines long-range trends for related factors (e.g., long-haul mileages driven by heavy trucks) and their impacts on reducing fuel consumption per cargo-ton-mile and the relative shares of total commercial fuel use among truck classes. It identifies the effects of these trends on U.S. petroleum consumption. The report also …
Date: June 10, 2009
Creator: Bertram, K. M.; Santini, D .J. & Vyas, A. D.
Object Type: Report
System: The UNT Digital Library