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Altus Times (Altus, Okla.), Vol. 106, No. 296, Ed. 1 Monday, March 21, 2005 (open access)

Altus Times (Altus, Okla.), Vol. 106, No. 296, Ed. 1 Monday, March 21, 2005

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 21, 2005
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, March 21, 2005 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, March 21, 2005

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: March 21, 2005
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Oklahoma Daily (Norman, Okla.), Vol. 88, No. 118, Ed. 1 Monday, March 21, 2005 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 88, No. 118, Ed. 1 Monday, March 21, 2005

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: March 21, 2005
Creator: Warren, Lee B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Baytown Sun (Baytown, Tex.), Vol. 84, No. 107, Ed. 1 Monday, March 21, 2005 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 84, No. 107, Ed. 1 Monday, March 21, 2005

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: March 21, 2005
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 90, No. 163, Ed. 1 Monday, March 21, 2005 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 90, No. 163, Ed. 1 Monday, March 21, 2005

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: March 21, 2005
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
A Dual-Mode Actinic EUV Mask Inspection Tool (open access)

A Dual-Mode Actinic EUV Mask Inspection Tool

To qualify the performance of non-actinic inspection tools, a novel EUV mask inspection system has been installed at the Advanced Light Source (ALS) synchrotron facility at Lawrence Berkeley National Laboratory. Similar to the older generation actinic mask inspection tool, the new system can operate in scanning mode, when mask blanks are scanned for defects using 13.5-nm in-band radiation to identify and map all locations on the mask that scatter a significant amount of EUV light. By modifying and optimizing beamline optics (11.3.2 at ALS) and replacing K-B focusing mirrors with a high quality Schwarzschild illuminator, the new system achieves an order of magnitude improvement on in-band EUV flux density at the mask, enabling faster scanning speed and higher sensitivity to smaller defects. Moreover, the system can also operate in imaging mode, when it becomes a zone-plate-based full-field EUV microscope with spatial resolution better than 100 nm. The microscope utilizes an off-axis setup, making it possible to obtain bright field images over a field-of-view of 5 x 5 {micro}m.
Date: March 21, 2005
Creator: Liu, Y.; Barty, A.; Gullikson, E.; S. Taylor, J.; Liddle, J. A. & Wood, O.
Object Type: Article
System: The UNT Digital Library
Bounds on Transport Coefficients of Porous Media (open access)

Bounds on Transport Coefficients of Porous Media

An analytical formulation of conductivity bounds by Bergman and Milton is used in a different way to obtain rigorous bounds on the real transport coefficients (electrical conductivity, thermal conductivity, and/or fluid permeability) of a fluid-saturated porous medium. These bounds do not depend explicitly on the porosity, but rather on two formation factors--one associated with the pore space and the other with the solid frame. Hashin-Shtrikman bounds for transport in random polycrystals of porous-material laminates will also be discussed.
Date: March 21, 2005
Creator: Berger, E. L.
Object Type: Article
System: The UNT Digital Library
Required Be Capsule Strength For Room Temperature Transport (open access)

Required Be Capsule Strength For Room Temperature Transport

The purpose of this memo is to lay out the criteria for the Be capsule strength necessary for room temperature transport. Ultimately we will test full thickness capsules by sealing high pressures inside, but currently we are limited to both thinner capsules and alternative measures of capsule material strength.
Date: March 21, 2005
Creator: Cook, B
Object Type: Report
System: The UNT Digital Library
Ultrasonic Examination of Double-Shell Tank 241-AP-102. February 2005 (open access)

Ultrasonic Examination of Double-Shell Tank 241-AP-102. February 2005

COGEMA Engineering Corporation (COGEMA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic nondestructive examination of selected portions of Double-Shell Tank 241-AP-102. The purpose of this examination was to provide information that could be used to evaluate the integrity of the wall of the primary tank. The requirements for the ultrasonic examination of Tank 241-AP-102 were to detect, characterize (identify, size, and locate), and record measurements made of any wall thinning, pitting, or cracks that might be present in the wall of the primary tank. Any measurements that exceed the requirements set forth in the Engineering Task Plan (ETP), RPP-22571 (Jensen 2004) and summarized on page 1 of this document, are reported to CH2M Hill and the Pacific Northwest National Laboratory (PNNL) for further evaluation. Under the contract with CH2M Hill, all data is to be recorded on disk and paper copies of all measurements are provided to PNNL for third-party evaluation. PNNL is responsible for preparing a report that describes the results of the COGEMA ultrasonic examinations.
Date: March 21, 2005
Creator: Pardini, Allan F. & Posakony, Gerald J.
Object Type: Report
System: The UNT Digital Library
An Integrated Modeling Analysis of Unsaturated Flow Patterns inFractured Rock (open access)

An Integrated Modeling Analysis of Unsaturated Flow Patterns inFractured Rock

Characterizing percolation patterns in unsaturated zones hasposed a greater challenge to numerical modeling investigations thancomparable saturated zone studies, because of the heterogeneous nature ofunsaturated media as well as the great number of variables impactingunsaturated zone flow. This paper presents an integrated modelingmethodology for quantitatively characterizing percolation patterns in theunsaturated zone of Yucca Mountain, Nevada, a proposed undergroundrepository site for storing high-level radioactive waste. It takes intoaccount the multiple coupled processes of air, water, heat flow andchemical isotopic transport in Yucca Mountain s highly heterogeneous,unsaturated fractured tuffs. The modeling approach integrates a widevariety of moisture, pneumatic, thermal, and isotopic geochemical fielddata into a comprehensive three-dimensional numerical model for modelinganalyses. Modeling results are examined against different types offield-measured data and then used to evaluate different hydrogeologicalconceptual models and their results of flow patterns in the unsaturatedzone. In particular, this integration model provides a much clearerunderstanding of percolation patterns and flow behavior through theunsaturated zone, both crucial issues in assessing repositoryperformance. The integrated approach for quantifying Yucca Mountain sflow system is also demonstrated to provide a comprehensive modeling toolfor characterizing flow and transport processes in complex subsurfacesystems.
Date: March 21, 2005
Creator: Wu, Yu-Shu; Lu, Guoping; Zhang, Keni; Pan, Lehua & Bodvarsson,Gudmundur S.
Object Type: Article
System: The UNT Digital Library
Mutual Passivation in Dilulte GaNxAs1-x Alloys (open access)

Mutual Passivation in Dilulte GaNxAs1-x Alloys

The dilute GaN{sub x}As{sub 1-x} alloys (with x up to 0.05) have exhibited many unusual properties as compared to the conventional binary and ternary semiconductor alloys. We report on a new effect in the GaN{sub x}As{sub 1-x} alloy system in which electrically active substitutional group IV donors and isoelectronic N atoms passivate each other's activity. This mutual passivation occurs in dilute GaN{sub x}As{sub 1-x} doped with group IV donors through the formation of nearest neighbor IV{sub Ga-}N{sub As} pairs when the samples are annealed under conditions such that the diffusion length of the donors is greater than or equal to the average distance between donor and N atoms. The passivation of the shallow donors and the N{sub As} atoms is manifested in a drastic reduction in the free electron concentration and, simultaneously, an increase in the fundamental band gap. This mutual passivation effect is demonstrated in both Si and Ge doped GaN{sub x}As{sub 1-x} alloys. Analytical calculations of the passivation process based on Ga vacancies mediated diffusion show good agreement with the experimental results.
Date: March 21, 2005
Creator: Yu, K.M.; Walukiewicz, W.; Wu, J.; Mars, D.E.; Scarpulla, M.A.; Dubon, O.D. et al.
Object Type: Article
System: The UNT Digital Library
The effects of zirconia morphology on methanol synthesis from COand H2 over Cu/ZrO2 catalysts: Part I -- Steady-State Studies (open access)

The effects of zirconia morphology on methanol synthesis from COand H2 over Cu/ZrO2 catalysts: Part I -- Steady-State Studies

The effect of zirconia phase on the activity and selectivityof Cu/ZrO2 for the hydrogenation of CO has been investigated. Relativelypure t-ZrO2 and m-ZrO2 were prepared with high surface areas (~; 145m2/g). Copper was then deposited onto the surface of these materials byeither incipient-wetness impregnation or deposition-precipitation. For afixed Cu surface area, Cu/m-ZrO2 was tenfold more active for methanolsynthesis than Cu/t-ZrO2 from a feed of 3/1 H2/CO at 3.0 MPa andtemperatures between 473 and 523 K. Cu/m-ZrO2 also exhibited a higherselectivity to methanol. Increasing the Cu surface area on m-ZrO2resulted in further improvement in activity with minimal change inselectivity. Methanol productivity increased linearly for both Cu/t-ZrO2and Cu/m-ZrO2 with increasing Cu surface area. The difference in inherentactivity of each phase paralleled the stronger and larger CO adsorptioncapacity of the Cu/m-ZrO2 as quantified by CO-TPD. The higher COadsorption capacity of Cu/m-ZrO2 is attributed to the presence of a highconcentration of anionic vacancies on the surface of m-ZrO2. Suchvacancies expose cus-Zr4+ cations, which act as Lewis acid centers andenhance the Bronsted acidity of adjacent Zr-OH groups. The presence ofcus-Zr4+ sites and adjacent Bronsted acidic Zr-OH groups contributes tothe adsorption of CO as HCOO-Zr groups, which are the initial precursorsto methanol.
Date: March 21, 2005
Creator: Rhodes, Michael J. & Bell, Alexis T.
Object Type: Article
System: The UNT Digital Library
Highly Mismatched Alloys for Intermediate Band Solar Cells (open access)

Highly Mismatched Alloys for Intermediate Band Solar Cells

It has long been recognized that the introduction of a narrow band of states in a semiconductor band gap could be used to achieve improved power conversion efficiency in semiconductor-based solar cells. The intermediate band would serve as a ''stepping stone'' for photons of different energy to excite electrons from the valence to the conduction band. An important advantage of this design is that it requires formation of only a single p-n junction, which is a crucial simplification in comparison to multijunction solar cells. A detailed balance analysis predicts a limiting efficiency of more than 50% for an optimized, single intermediate band solar cell. This is higher than the efficiency of an optimized two junction solar cell. Using ion beam implantation and pulsed laser melting we have synthesized Zn{sub 1-y}Mn{sub y}O{sub x}Te{sub 1-x} alloys with x<0.03. These highly mismatched alloys have a unique electronic structure with a narrow oxygen-derived intermediate band. The width and the location of the band is described by the Band Anticrossing model and can be varied by controlling the oxygen content. This provides a unique opportunity to optimize the absorption of solar photons for best solar cell performance. We have carried out systematic studies of the …
Date: March 21, 2005
Creator: Walukiewicz, W.; Yu, K. M.; Wu, J.; Ager, J. W., III; Shan, W.; Scrapulla, M. A. et al.
Object Type: Article
System: The UNT Digital Library
The Decovalex III Project: A Summary of Activities and LessonsLearned (open access)

The Decovalex III Project: A Summary of Activities and LessonsLearned

Initiated in 1992, the DECOVALEX project is an international collaboration for advancing the understanding and modeling of coupled thermo-hydro-mechanical (THM) processes in geologic systems. The project has made important scientific achievements through three stages and is progressing in its fourth stage. It has played a key role in the development of mathematical modeling and in situ testing of coupled THM processes in fractured rock and buffer/backfill materials, a subject of importance for performance assessment of radioactive waste geologic repositories. This paper summarizes studies under the most recent stage of the project, DECOVALEX III (2000-2003). These studies include those of two major field experiments: (a) the FEBEX experiment at Grimsel, Switzerland, investigating coupled THM processes in a crystalline rock-bentonite system, and (b) the Drift Scale Test (DST) experiment at Yucca Mountain, Nevada, investigating coupled THM processes in unsaturated tuff. These are two of the largest multiyear heater tests undertaken to date for the study of coupled THM processes in geological systems. In addition, three so-called benchmark tests are also studied to evaluate the impact of coupled THM processes under different scenarios and geometries. Within the DECOVALEX project, multiple research teams participated in each of the studies, using different approaches and computer …
Date: March 21, 2005
Creator: Tsang, Chin-Fu; Jing, Lanru; Stephansson, Ove & Kautsky, Fritz
Object Type: Article
System: The UNT Digital Library
Strees Corrosion Cracking Initiation of Ni-Bassed Alloys in High Temperature Water (open access)

Strees Corrosion Cracking Initiation of Ni-Bassed Alloys in High Temperature Water

The goal of the work is to provide stress corrosion cracking (SCC) initiation data for Alloy 600 that is not compromised by (1) specimens that suffer from stress relaxation, (2) specimens which have an unknown stress state, (3) specimens which are tested at unknown positions electrochemically relative to the Ni/NiO phase transition, and (4) testing which relies on the period of time between specimen inspection intervals to estimate SCC initiation times. The current study was aimed at studying the effects of temperature and coolant hydrogen concentration on SCC initiation in high purity, high temperature water.
Date: March 21, 2005
Creator: Richey, E & Morton, D
Object Type: Article
System: The UNT Digital Library
A Variable-resolution Surface Wave Dispersion Study of Eurasia, North Africa, and Surrounding Regions (open access)

A Variable-resolution Surface Wave Dispersion Study of Eurasia, North Africa, and Surrounding Regions

This paper presents the results of a large-scale study of surface wave dispersion performed across Eurasia and North Africa. Improvements were made to previous surface wave work by enlarging the study region, increasing path density, improving spatial resolution, and expanding the period range. This study expands the coverage area northwards and eastwards relative to a previous dispersion analysis, which covered only North Africa and the Middle East. We have significantly increased the number of seismograms examined and group velocity measurements made. We have now made good quality dispersion measurements for about 30,000 Rayleigh wave and 20,000 Love wave paths, and have incorporated measurements from several other researchers into the study. A conjugate gradient method was employed for the group velocity tomography, which improved the inversion from the previous study by adopting a variable smoothness. This technique allows us to go to higher resolution where the data allow without producing artifacts. The current results include both Love and Rayleigh wave inversions across the region for periods from 7 to 100 seconds at 1{sup o} resolution. Short period group velocities are sensitive to slow velocities associated with large sedimentary features such as the Caspian Sea, West Siberian Platform, Mediterranean Sea, Bay of …
Date: March 21, 2005
Creator: Pasyanos, M E
Object Type: Article
System: The UNT Digital Library
Evaluation of Alternative Field Buses for Lighting Control Applications (open access)

Evaluation of Alternative Field Buses for Lighting Control Applications

The Subcontract Statement of Work consists of two major tasks. This report is the Final Report in fulfillment of the contract deliverable for Task 1. The purpose of Task 1 was to evaluate existing and emerging protocols and standards for interfacing sensors and controllers for communicating with integrated lighting control systems in commercial buildings. The detailed task description follows: Task 1. Evaluate alternative sensor/field buses. The objective of this task is to evaluate existing and emerging standards for interfacing sensors and controllers for communicating with integrated lighting control systems in commercial buildings. The protocols to be evaluated will include at least: (1) 1-Wire Net, (2) DALI, (3) MODBUS (or appropriate substitute such as EIB) and (4) ZigBee. The evaluation will include a comparative matrix for comparing the technical performance features of the different alternative systems. The performance features to be considered include: (1) directionality and network speed, (2) error control, (3) latency times, (4) allowable cable voltage drop, (5) topology, and (6) polarization. Specifically, Subcontractor will: (1) Analyze the proposed network architecture and identify potential problems that may require further research and specification. (2) Help identify and specify additional software and hardware components that may be required for the communications …
Date: March 21, 2005
Creator: Koch, Ed & Rubinstein, Francis
Object Type: Report
System: The UNT Digital Library
Corrosion Rate of Alloy 22 as a Function of Immersion Time (open access)

Corrosion Rate of Alloy 22 as a Function of Immersion Time

Alloy 22 (N06022) is a nickel (Ni) based alloy containing nominally 22% Chromium (Cr), 13% Molybdenum (Mo) and 3% tungsten (W). Alloy 22 is highly resistant to general and localized corrosion such as pitting corrosion and stress corrosion cracking. Due to the formation of a stable passive film, when Alloy 22 is immersed in certain electrolytes, its corrosion potential (E{sub corr}) increases and its corrosion rate (CR) decreases as a function of the immersion time. This paper discusses the evolution of E{sub corr} and corrosion rate (CR) of creviced Alloy 22 specimens in six different mixtures of sodium chloride (NaCl) and potassium nitrate (KNO{sub 3}) at 100 C. Two types of specimens were used, polished as-welded (ASW) and as-welded solution plus heat-treated (ASW+SHT). The latter contained the black annealing oxide film on the surface. Results show that, for the two type of materials, as the immersion time increases, E{sub corr} increased and the CR decreased. Even for concentrated brine solutions at 100 C the CR was < 50 nm/year after more than 100 days immersion.
Date: March 21, 2005
Creator: Estill, J. C.; Hust, G. A.; King, K. J. & Rebak, R. B.
Object Type: Article
System: The UNT Digital Library
Finite Difference Modeling of Wave Progpagation in Acoustic TiltedTI Media (open access)

Finite Difference Modeling of Wave Progpagation in Acoustic TiltedTI Media

Based on an acoustic assumption (shear wave velocity is zero) and a dispersion relation, we derive an acoustic wave equation for P-waves in tilted transversely isotropic (TTI) media (transversely isotropic media with a tilted symmetry axis). This equation has fewer parameters than an elastic wave equation in TTI media and yields an accurate description of P-wave traveltimes and spreading-related attenuation. Our TTI acoustic wave equation is a fourth-order equation in time and space. We demonstrate that the acoustic approximation allows the presence of shear waves in the solution. The substantial differences in traveltime and amplitude between data created using VTI and TTI assumptions is illustrated in examples.
Date: March 21, 2005
Creator: Zhang, Linbin; Rector, James W., III & Hoversten, G. Michael
Object Type: Article
System: The UNT Digital Library
Supreme Court Nominations Not Confirmed, 1789-2004 (open access)

Supreme Court Nominations Not Confirmed, 1789-2004

This report discusses Supreme Court nominations that were not confirmed between 1789 and 2004 (comprising 34 nominations). Over the course of United States history, approximately one-quarter of the presidential nominations to the U.S. Supreme Court have failed to place a new Associate or Chief Justice on the bench.
Date: March 21, 2005
Creator: Hogue, Henry B.
Object Type: Report
System: The UNT Digital Library
Air Force FB-22 Bomber Concept (open access)

Air Force FB-22 Bomber Concept

The Air Force has expressed interest in developing a bomber variant of the F-22A Raptor to "bridge the gap" between today's bombers and a follow-on bomber in 2037. Questions exist regarding the FB-22's feasibility, cost, and combat potential.
Date: March 21, 2005
Creator: Bolkcom, Christopher
Object Type: Report
System: The UNT Digital Library
Spectrum Management: Auctions (open access)

Spectrum Management: Auctions

This report discusses the radio frequency spectrum that is used for all forms of wireless communications, including cellular telephony, paging, personal communications service, radio and television broadcast, telephone radio relay, aeronautical and maritime radio navigation, and satellite command and control.
Date: March 21, 2005
Creator: Moore, Linda K.
Object Type: Report
System: The UNT Digital Library
Nuclear Arms Control: The U.S.-Russian Agenda (open access)

Nuclear Arms Control: The U.S.-Russian Agenda

None
Date: March 21, 2005
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Consumer Bankruptcy and Household Debt (open access)

Consumer Bankruptcy and Household Debt

This report provides information about the Consumer Bankruptcy and Household Debt. The principal impetus behind bankruptcy reform is high number of consumer bankruptcy filings.
Date: March 21, 2005
Creator: Jickling, Mark
Object Type: Report
System: The UNT Digital Library