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Spectroscopic study of partially-ordered semiconductor heterojunction under high pressure and high magnetic field (open access)

Spectroscopic study of partially-ordered semiconductor heterojunction under high pressure and high magnetic field

Photoluminescence upconversion (PLU) is a phenomenon in which a sample emits photons with energy higher than that of the excitation photon. This effect has been observed in many materials including rare earth ions doped in insulating hosts and semiconductor heterostructures without using high power lasers as the excitation source. Recently, this effect has been observed also in partially CuPt-ordered GaInP{sub 2} epilayers grown on GaAs substrates. As a spectroscopic technique photoluminescence upconversion is particularly well suited for studying band alignment at heterojunction interface. The value of band-offset has been determined with meV precision using magneto-photoluminescence. Using the fact that the pressure coefficient of electrons in GaAs is higher than those in GaInP{sub 2} they have been able to manipulate the band-offset at the GaInP/GaAs interface. By converting the band-offset from Type I to Type II they were able to demonstrate that the efficiency of the upconversion process is greatly enhanced by a Type II band-offset.
Date: December 31, 2000
Creator: Yu, P.Y.; Martinez, G.; Zeman, J. & Uchida, K.
Object Type: Article
System: The UNT Digital Library

[Stone Jaguars in Enclosure]

Photograph of two stone jaguars in a garden, each holding something round. Two little boys and adults are walking in the background, behind glass.
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library
Sum frequency generation vibrational spectroscopy studies of adsorbates on Pt(111): Studies of CO at high pressures and temperatures, coadsorbed with olefins and its role as a poison in ethylene hydrogenation (open access)

Sum frequency generation vibrational spectroscopy studies of adsorbates on Pt(111): Studies of CO at high pressures and temperatures, coadsorbed with olefins and its role as a poison in ethylene hydrogenation

High pressure high temperature CO adsorption and coadsorption with ethylene and propylene on Pt(111) was monitored in situ with infrared-visible sum frequency generation (SFG). At high pressures and high temperatures, CO dissociates on a Pt(111) surface to form carbon. At 400 torr CO pressure and 673K, CO modifies the Pt(111) surface through a carbonyl intermediate, and dissociates to leave carbon on the surface. SFG was used to follow the CO peak evolution from monolayer adsorption in ultra high vacuum (UHV) to 400 torr CO pressure. At this high pressure, a temperature dependence study from room temperature to 823K was carried out. Auger electron spectroscopy was used to identify carbon on the surface CO coadsorption with ethylene and CO coadsorption with propylene studies were carried out with 2-IR 1-visible SFG. With this setup, two spectral ranges covering the C-H stretch range and the CO stretch range can be monitored simultaneously. The coadsorption study with ethylene reveals that after 5L ethylene exposure on a Pt(111) surface to form ethylidyne , CO at high pressures cannot completely displace the ethylidyne from the surface. Instead, CO first adsorbs on defect sites at low pressures and then competes with ethylidyne for terrace sites at high …
Date: December 31, 2000
Creator: Kung, Kyle Yi
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Summary of Miniature NMR Development (open access)

Summary of Miniature NMR Development

The effort in this project has been in 3 distinct directions: (1) First, they focused on development of miniature microfabricated micro-coil NMR detectors with maximum Signal-to-Noise (SNR) ratio. (2) Secondly, they focused on design of miniature micro-coil NMR detectors that have minimal effect on the NMR spectrum distortions. (3) Lastly they focused on the development of a permanent magnet capable of generating fields on the order of 1 Tesla with better than 10 ppm uniformity.
Date: December 31, 2000
Creator: Friedman, Gennady & Feinerman, Alan
Object Type: Report
System: The UNT Digital Library
Thermal Energy for Space Cooling--Federal Technology Alert (open access)

Thermal Energy for Space Cooling--Federal Technology Alert

Cool storage technology can be used to significantly reduce energy costs by allowing energy-intensive, electrically driven cooling equipment to be predominantly operated during off peak hours when electricity rates are lower. This Federal Technology Alert, which is sponsored by DOE's Federal Energy Management Program (FEMP), describes the basic types of cool storage technologies and cooling system integration options. In addition, it defines the savings potential in the federal sector, presents application advice, and describes the performance experience of specific federal users. The results of a case study of a GSA building using cool storage technology are also provided.
Date: December 31, 2000
Creator: Brown, Daryl R.
Object Type: Report
System: The UNT Digital Library
Thermal Energy Storage for Space Cooling--Federal Technology Alert (open access)

Thermal Energy Storage for Space Cooling--Federal Technology Alert

Cool storage technology can be used to significantly reduce energy costs by allowing energy-intensive, electrically driven cooling equipment to be predominantly operated during off peak hours when electricity rates are lower. This Federal Technology Alert, which is sponsored by DOE's Federal Energy Management Program (FEMP), describes the basic types of cool storage technologies and cooling system integration options. In addition, it defines the savings potential in the federal sector, presents application advice, and describes the performance experience of specific federal users. The results of a case study of a GSA building using cool storage technology are also provided.
Date: December 31, 2000
Creator: Brown, Daryl R
Object Type: Report
System: The UNT Digital Library

[Two small boys look at the aquarium]

Two boys at the Aquarium enjoy looking at the fish. A yellow fish is in the foreground of the photo.
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Two stone jaguars in a garden]

Two stone statues of jaguars sit in a garden.
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library
USE OF SONICATION FOR IN-WELL SOFTENING OF SEMIVOLATILE ORGANIC COMPOUNDS (open access)

USE OF SONICATION FOR IN-WELL SOFTENING OF SEMIVOLATILE ORGANIC COMPOUNDS

This project investigates the in-situ degradation of semivolatile organic compounds (SVOCs) and volatile organic compounds (VOCs) using in-well sonication, in-well vapor stripping, and bioremediation. Pretreating groundwaters with sonication techniques in-situ would form VOCs that can be effectively removed by in-well vapor stripping and bioremediation. The mechanistic studies focus on the coupling of megasonics and ultrasonics to ''soften'' (i.e., partially degrade) the SVOCs; oxidative reaction mechanism studies; surface corrosion studies (on the reactor walls/well); enhancement due to addition of oxidants, quantification of the hydroxyl radical formation; identification/quantification of degradation products; volatility/degradability of the treated waters; development of a computer simulation model to describe combined in-well sonication/in-well vapor stripping/bioremediation; systems analysis/economic analysis; large laboratory-scale experiment verification; and field demonstration of the integrated technology. Benefits of this approach include: (1) Remediation is performed in-situ; (2) The treatment systems complement each other; their combination can drastically reduce or remove SVOCs and VOCs; (3) Ability to convert hard-to-degrade organics into more volatile organic compounds; (4) Ability to remove residual VOCs and ''softened'' SVOCs through the combined action of in-well vapor stripping and biodegradation; (5) Does not require handling or disposing of water at the ground surface; and (6) Cost-effective and improved efficiency, resulting in shortened …
Date: December 31, 2000
Creator: Peters, Robert W.
Object Type: Report
System: The UNT Digital Library
Utility Advanced Turbine Systems Program (ATS) Technical Readiness Testing and Pre-Commercial Demonstration (open access)

Utility Advanced Turbine Systems Program (ATS) Technical Readiness Testing and Pre-Commercial Demonstration

The objective of the ATS program is to develop ultra-high efficiency, environmentally superior and cost competitive gas turbine systems for base load application in utility, independent power producer and industrial markets. Specific performance targets have been set using natural gas as the primary fuel: {lg_bullet} System efficiency that will exceed 60%(lower heating value basis) on natural gas for large scale utility turbine systems; for industrial applications, systems that will result in a 15% improvement in heat rate compared to currently available gas turbine systems. {lg_bullet} An environmentally superior system that will not require the use of post combustion emissions controls under full load operating conditions. {lg_bullet} Busbar energy costs that are 10% less than current state-of-the-art turbine systems, while meeting the same environmental requirements. {lg_bullet} Fuel-flexible designs that will operate on natural gas but are capable of being adapted to operate on coal-derived or biomass fuels. {lg_bullet} Reliability-Availability-Maintainability (RAM) that is equivalent to the current turbine systems. {lg_bullet} Water consumption minimized to levels consistent with cost and efficiency goals. {lg_bullet} Commercial systems that will enter the market in the year 2000. In Phase I of the ATS program, Siemens Westinghouse found that efficiency significantly increases when the traditional combined-cycle power …
Date: December 31, 2000
Creator: Westinghouse, Siemens
Object Type: Report
System: The UNT Digital Library

[View of a shark from below]

A shark's white underbelly shows as he swims overhead.
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Visitors in a glass tunnel look at sharks swimming past]

Several visitors in a glass tunnel gaze at sharks swimming past them.
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Visitors walk in a glass tunnel through the Aquarium]

A crowd of people walk in a glass tunnel through the Aquarium.
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library
[Wheeler Avenue Baptist Church Bulletin: December 31, 2000] (open access)

[Wheeler Avenue Baptist Church Bulletin: December 31, 2000]

Church bulletin listing the order of worship for the 7:30 and 11:00 Sunday morning services at the Wheeler Avenue Baptist Church, as well as various notes about upcoming events, congregational news, and other information of relevance to church members.
Date: December 31, 2000
Creator: Wheeler Avenue Baptist Church (Houston, Tex.)
Object Type: Pamphlet
System: The Portal to Texas History

[Woman holding small child at counter]

None
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Woman with computer photographing another woman]

None
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Young couple sit inside a stone structure, near a window]

A young man and woman sit on the floor together inside a stone structure, while the young man looks up and out a nearby window.
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 79, No. 34, Ed. 1 Saturday, December 30, 2000 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 79, No. 34, Ed. 1 Saturday, December 30, 2000

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: December 30, 2000
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Demonstration of Decision Support Tools for Sustainable Development - An Application on Alternative Fuels in the Greater Yellowstone-Teton Region (open access)

Demonstration of Decision Support Tools for Sustainable Development - An Application on Alternative Fuels in the Greater Yellowstone-Teton Region

The Demonstration of Decision Support Tools for Sustainable Development project integrated the Bechtel/Nexant Industrial Materials Exchange Planner and the Idaho National Engineering and Environmental Laboratory System Dynamic models, demonstrating their capabilities on alternative fuel applications in the Greater Yellowstone-Teton Park system. The combined model, called the Dynamic Industrial Material Exchange, was used on selected test cases in the Greater Yellow Teton Parks region to evaluate economic, environmental, and social implications of alternative fuel applications, and identifying primary and secondary industries. The test cases included looking at compressed natural gas applications in Teton National Park and Jackson, Wyoming, and studying ethanol use in Yellowstone National Park and gateway cities in Montana. With further development, the system could be used to assist decision-makers (local government, planners, vehicle purchasers, and fuel suppliers) in selecting alternative fuels, vehicles, and developing AF infrastructures. The system could become a regional AF market assessment tool that could help decision-makers understand the behavior of the AF market and conditions in which the market would grow. Based on this high level market assessment, investors and decision-makers would become more knowledgeable of the AF market opportunity before developing detailed plans and preparing financial analysis.
Date: December 30, 2000
Creator: Shropshire, D.E.; Cobb, D.A.; Worhach, P.; Jacobson, J.J. & Berrett, S.
Object Type: Report
System: The UNT Digital Library
[Funeral Program for Mr. Eric Deshawn Dykes "E-Love", December 30, 2000] (open access)

[Funeral Program for Mr. Eric Deshawn Dykes "E-Love", December 30, 2000]

Funeral program for Mr. Eric Deshawn Dykes "E-Love", born September 6 1971 and died December 27, 2000. The funeral was held December 30, 2000 at Greater Love Missionary Baptist Church, officiated by Reverend L. J. Gillespie. Funeral arrangements were made through the Lewis Funeral Home and he was buried in Meadowlawn Memorial Park in San Antonio, Texas.
Date: December 30, 2000
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History
Pawhuska Journal-Capital (Pawhuska, Okla.), Vol. 90, No. 105, Ed. 1 Saturday, December 30, 2000 (open access)

Pawhuska Journal-Capital (Pawhuska, Okla.), Vol. 90, No. 105, Ed. 1 Saturday, December 30, 2000

Semiweekly newspaper from Pawhuska, Oklahoma that includes local, state, and national news along with advertising.
Date: December 30, 2000
Creator: Gann, Sherry
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 85, No. 360, Ed. 1 Saturday, December 30, 2000 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 85, No. 360, Ed. 1 Saturday, December 30, 2000

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: December 30, 2000
Creator: Quinnelly, Lorrie J.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Structure Based Predictive Model for Coal Char Combustion (open access)

Structure Based Predictive Model for Coal Char Combustion

This unique collaborative project has taken a very fundamental look at the origin of structure, and combustion reactivity of coal chars. It was a combined experimental and theoretical effort involving three universities and collaborators from universities outside the U.S. and from U.S. National Laboratories and contract research companies. The project goal was to improve our understanding of char structure and behavior by examining the fundamental chemistry of its polyaromatic building blocks. The project team investigated the elementary oxidative attack on polyaromatic systems, and coupled with a study of the assembly processes that convert these polyaromatic clusters to mature carbon materials (or chars). We believe that the work done in this project has defined a powerful new science-based approach to the understanding of char behavior. The work on aromatic oxidation pathways made extensive use of computational chemistry, and was led by Professor Christopher Hadad in the Department of Chemistry at Ohio State University. Laboratory experiments on char structure, properties, and combustion reactivity were carried out at both OSU and Brown, led by Principle Investigators Joseph Calo, Robert Essenhigh, and Robert Hurt. Modeling activities were divided into two parts: first unique models of crystal structure development were formulated by the team at …
Date: December 30, 2000
Creator: Hurt, Robert; Calo, Joseph; Essenhigh, Robert & Hadad, Christopher
Object Type: Report
System: The UNT Digital Library
Agricultural Trade in the 106th Congress: A Review of Issues (open access)

Agricultural Trade in the 106th Congress: A Review of Issues

The 106th Congress considered a number of trade policy developments against a backdrop of weak foreign demand and large world supplies of agricultural commodities. The U.S. Department of Agriculture reports that the value of U.S. agricultural exports fell between FY1996 (a record year) and FY1999 by almost $11 billion, to $49.2 billion. Agricultural exports did climb back to $50.9 billion in FY2000, and are now projected at $53 billion in FY2001. However, the pace of recovery concerned many agricultural groups and their supporters in Congress. Although they recognize that many world economic, farm production, political, and weather factors influence exports, many of these groups believe that the agricultural sector's future prosperity also depends upon such U.S. trade policies as: 1) encouraging China's entry into the World Trade Organization (WTO), with its binding rules and responsibilities; 2) exempting agricultural exports from U.S. unilateral economic sanctions; 3) fully using export and food aid programs; and 4) aggressively battling foreign-imposed barriers to the movement of U.S. farm products. A few U.S. farm groups are wary of such approaches.
Date: December 29, 2000
Creator: Becker, Geoffrey S.; Hanrahan, Charles E. & Jurenas, Remy
Object Type: Report
System: The UNT Digital Library