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{sup 17}O NMR Investigation of Oxidative Degradation in Polymers Under Gamma-Irradiation (open access)

{sup 17}O NMR Investigation of Oxidative Degradation in Polymers Under Gamma-Irradiation

The {gamma}-irradiated-oxidation of pentacontane (C{sub 50}H{sub 102}) and the polymer polyisoprene was investigated as a function of oxidation level using {sup 17}O nuclear magnetic resonance (NMR) spectroscopy. It is demonstrated that by using {sup 17}O labeled O{sub 2} gas during the {gamma}-irradiation process, details about the oxidative degradation mechanisms can be directly obtained from the analysis of the {sup 17}O NMR spectra. Production of carboxylic acids is the primary oxygen-containing functionality during the oxidation of pentacontane, while ethers and alcohols are the dominant oxidation product observed for polyisoprene. The formation of ester species during the oxidation process is very minor for both materials, with water also being produced in significant amounts during the radiolytic oxidation of polyisoprene. The ability to focus on the oxidative component of the degradation process using {sup 17}O NMR spectroscopy demonstrates the selectivity of this technique over more conventional approaches.
Date: March 8, 2000
Creator: Alam, Todd M.; Celina, Mathias C.; Assink, Roger A.; Clough, Roger Lee & Gillen, Kenneth T.
Object Type: Article
System: The UNT Digital Library
Improvements in bis(cyclopentadienyl)magnesium purity as determined with gas chromatography-mass spectroscopy (open access)

Improvements in bis(cyclopentadienyl)magnesium purity as determined with gas chromatography-mass spectroscopy

Bis(cyclopentadienyl)magnesium (MgCp2) is used commonly as a source for doping nitride materials with magnesium. Increased oxygen incorporation known to accompany the use of MgCp2 makes the purity of this precursor an important consideration in nitride CVD. Gas chromatography-mass spectroscopy (GCMS) methods have now been developed for the identification of volatile impurities in MgCp2. Diethylether, an oxygen containing organic compound (CH{sub 3}CH{sub 2}OCH{sub 2}CH{sub 3}), and additional organic impurities were found in the MgCp2 supplied by three manufacturers. Subsequent refinements in the synthetic processes by these companies have resulted in the availability of MgCp2 free of ether and other organic impurities as determined by GCMS.
Date: March 8, 2000
Creator: BARTRAM,MICHAEL E.
Object Type: Article
System: The UNT Digital Library
Imaging System for the Automated Determination of Microscopical Properties in Hardened Portland Concrete (open access)

Imaging System for the Automated Determination of Microscopical Properties in Hardened Portland Concrete

During this CRADA, Honeywell FM and T and MoDOT personnel designed a unique scanning system (including both hardware and software) that can be used to perform an automated scan and evaluation of a concrete sample. The specific goals of the CRADA were: (1) Develop a combined system integration, image acquisition, and image analysis approach to mimic the manual scanning and evaluation process. Produce a prototype system which can: (a) automate the scanning process to improve its speed and efficiency; (b) reduce operator fatigue; and (c) improve the consistency of the evaluation process. (2) Capture and preserve the baseline knowledge used by the MoDOT experts in performing the evaluation process. At the present time, the evaluation expertise resides in two MoDOT personnel. Automation of the evaluation process will allow that knowledge to be captured, preserved, and used for training purposes. (3) Develop an approach for the image analysis which is flexible and extensible in order to accommodate the inevitable pathologies that arise in the evaluation process. Such pathologies include features such as cracks and fissures, voids filled with paste or debris, and multiple, overlapping voids. FM and T personnel used image processing, pattern recognition, and system integration skills developed for other …
Date: March 8, 2000
Creator: Baumgart, C.W.; Cave, S.P. & Linder, K.E.
Object Type: Report
System: The UNT Digital Library
Defect diffusion during annealing of low-energy ion-implanted silicon (open access)

Defect diffusion during annealing of low-energy ion-implanted silicon

We present a new approach for investigating the kinetics of defect migration during annealing of low-energy, ion-implanted silicon, employing a combination of computer simulations and atomic-resolution tunneling microscopy. Using atomically-clean Si(111)-7x7 as a sink for bulk point defects created by 5 keV Xe and Ar irradiation, we observe distinct, temperature-dependent surface arrival rates for vacancies and interstitials. A combination of simulation tools provides a detailed description of the processes that underly the observed temperature-dependence of defect segregation, and the predictions of the simulations agree closely with the experimental observations.
Date: March 8, 2000
Creator: Bedrossian, P J; Caturla, M-J & Diaz de la Rubia, T
Object Type: Article
System: The UNT Digital Library
Recent plant studies using Victoria 2.0 (open access)

Recent plant studies using Victoria 2.0

VICTORIA 2.0 is a mechanistic computer code designed to analyze fission product behavior within the reactor coolant system (RCS) during a severe nuclear reactor accident. It provides detailed predictions of the release of radioactive and nonradioactive materials from the reactor core and transport and deposition of these materials within the RCS and secondary circuits. These predictions account for the chemical and aerosol processes that affect radionuclide behavior. VICTORIA 2.0 was released in early 1999; a new version VICTORIA 2.1, is now under development. The largest improvements in VICTORIA 2.1 are connected with the thermochemical database, which is being revised and expanded following the recommendations of a peer review. Three risk-significant severe accident sequences have recently been investigated using the VICTORIA 2.0 code. The focus here is on how various chemistry options affect the predictions. Additionally, the VICTORIA predictions are compared with ones made using the MELCOR code. The three sequences are a station blackout in a GE BWR and steam generator tube rupture (SGTR) and pump-seal LOCA sequences in a 3-loop Westinghouse PWR. These sequences cover a range of system pressures, from fully depressurized to full system pressure. The chief results of this study are the fission product fractions that …
Date: March 8, 2000
Creator: Bixler, Nathan E. & Gasser, Ronald D.
Object Type: Article
System: The UNT Digital Library
University Press (Beaumont, Tex.), Vol. 76, No. 38, Ed. 1 Wednesday, March 8, 2000 (open access)

University Press (Beaumont, Tex.), Vol. 76, No. 38, Ed. 1 Wednesday, March 8, 2000

Semiweekly newspaper from Lamar University in Beaumont, Texas that includes local, national, and campus news along with advertising.
Date: March 8, 2000
Creator: Bordeman, Christina
Object Type: Newspaper
System: The Portal to Texas History
Oral History Interview with Ray Bowden, March 8, 2000 transcript

Oral History Interview with Ray Bowden, March 8, 2000

The National Museum of the Pacific War presents an oral interview with Ray Bowden. Bowden joined the Navy in November 1938 and received basic training in San Diego. He went aboard the USS Oklahoma (BB-37) and was made coxswain of a liberty boat. During the attack on Pearl Harbor, he ran to his battle station. By the time he arrived, the ship had already been torpedoed seven times and was beginning to roll. He was hit by a piece of shrapnel that killed the men next to him but left him with only a broken rib. After the attack, he searched for his brother, who was also aboard the Oklahoma. He was safe at a nearby Marine encampment. Bowden participated in one diving mission as part of the effort to clean up the harbor, assessing damage and closing water-tight doors. Late in the war, he was transferred to the USS Santee (ACV-29) as a chief boatswain’s mate. He encountered kamikazes near Okinawa. At the end of the war, Bowden had enough points to be discharged but chose to remain in the Navy until 1947.
Date: March 8, 2000
Creator: Bowden, Ray
Object Type: Sound
System: The Portal to Texas History
Oral History Interview with Ray Bowden, March 8, 2000 (open access)

Oral History Interview with Ray Bowden, March 8, 2000

The National Museum of the Pacific War presents an oral interview with Ray Bowden. Bowden joined the Navy in November 1938 and received basic training in San Diego. He went aboard the USS Oklahoma (BB-37) and was made coxswain of a liberty boat. During the attack on Pearl Harbor, he ran to his battle station. By the time he arrived, the ship had already been torpedoed seven times and was beginning to roll. He was hit by a piece of shrapnel that killed the men next to him but left him with only a broken rib. After the attack, he searched for his brother, who was also aboard the Oklahoma. He was safe at a nearby Marine encampment. Bowden participated in one diving mission as part of the effort to clean up the harbor, assessing damage and closing water-tight doors. Late in the war, he was transferred to the USS Santee (ACV-29) as a chief boatswain’s mate. He encountered kamikazes near Okinawa. At the end of the war, Bowden had enough points to be discharged but chose to remain in the Navy until 1947.
Date: March 8, 2000
Creator: Bowden, Ray
Object Type: Text
System: The Portal to Texas History
Perry Daily Journal (Perry, Okla.), Vol. 107, No. 48, Ed. 1 Wednesday, March 8, 2000 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 107, No. 48, Ed. 1 Wednesday, March 8, 2000

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: March 8, 2000
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, March 8, 2000 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, March 8, 2000

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: March 8, 2000
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Altus Times (Altus, Okla.), Vol. 100, No. 302, Ed. 1 Wednesday, March 8, 2000 (open access)

Altus Times (Altus, Okla.), Vol. 100, No. 302, Ed. 1 Wednesday, March 8, 2000

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 8, 2000
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Campaign Financing: Highlights and Chronology of Current Federal Law (open access)

Campaign Financing: Highlights and Chronology of Current Federal Law

This report provides a summary of major provisions of federal law and a chronology of key legislative and judicial actions.
Date: March 8, 2000
Creator: Cantor, Joseph E.
Object Type: Report
System: The UNT Digital Library
Campaign Financing: Highlights and Chronology of Current Federal Law (open access)

Campaign Financing: Highlights and Chronology of Current Federal Law

Current law governing financial activity of campaigns for federal office is based on two principal statutes: the Federal Election Campaign Act (FECA) of 1971, as amended in 1974, 1976, and 1979, and the Revenue Act of 1971. These laws were enacted to remedy widely perceived shortcomings of existing law, the Corrupt Practices Act of 1925, and in response to reports of campaign finance abuses over the years, culminating in the 1972-1974 Watergate scandal. This report provides a summary of major provisions of federal law and a chronology of key legislative and judicial actions.
Date: March 8, 2000
Creator: Cantor, Joseph E.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 78, No. 111, Ed. 1 Wednesday, March 8, 2000 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 78, No. 111, Ed. 1 Wednesday, March 8, 2000

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: March 8, 2000
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Statistical Evaluation of Effluent Monitoring Data for the 200 Area Treated Effluent Disposal Facility (open access)

Statistical Evaluation of Effluent Monitoring Data for the 200 Area Treated Effluent Disposal Facility

This report updates the original effluent variability study for the 200 Area Treated Effluent Disposal Facility (TEDF) and provides supporting justification for modifying the effluent monitoring portion of the discharge permit. Four years of monitoring data were evaluated and used to statistically justify changes in permit effluent monitoring conditions. As a result, the TEDF effluent composition and variability of the effluent waste stream are now well defined.
Date: March 8, 2000
Creator: Chou, Charissa J & Johnson, Vernon G
Object Type: Report
System: The UNT Digital Library
Statistical Evaluation of Effluent Monitoring Data for the 200 Area Treated Effluent Disposal Facility (open access)

Statistical Evaluation of Effluent Monitoring Data for the 200 Area Treated Effluent Disposal Facility

This report updates the original effluent variability study for the 200 Area Treated Effluent Disposal Facility (TEDF) and provides supporting justification for modifying the effluent monitoring portion of the discharge permit. Four years of monitoring data were evaluated and used to statistically justify changes in permit effluent monitoring conditions. As a result, the TEDF effluent composition and variability of the effluent waste stream are now well defined.
Date: March 8, 2000
Creator: Chou, Charissa J. & Johnson, Vernon G.
Object Type: Report
System: The UNT Digital Library
Computational Study of Polarizabilities and Second Hyperpolarizabilities of Inorganic Transition Metal Thiometalates and Metalates in Solution (open access)

Computational Study of Polarizabilities and Second Hyperpolarizabilities of Inorganic Transition Metal Thiometalates and Metalates in Solution

This article discusses a computational study of polarizabilities and second hyperpolarizabilities of inorganic transition metal thiometalates and metalates in solution.
Date: March 8, 2000
Creator: Cundari, Thomas R., 1964-; Kurtz, Henry A. & Zhou, Tie
Object Type: Article
System: The UNT Digital Library
Facility Effluent Monitoring Plan for the Waste Receiving and Processing (WRAP) Facility (open access)

Facility Effluent Monitoring Plan for the Waste Receiving and Processing (WRAP) Facility

A facility effluent monitoring plan is required by the U.S. Department of Energy in Order 5400.1 for any operations that involve hazardous materials and radioactive substances that could impact employee public safety, or the environment. This facility effluent monitoring plan assesses effluent monitoring systems and evaluates whether these systems are adequate to ensure the public health and safety as specified in applicable federal, state, and local requirements. This facility effluent monitoring plan ensures long-range integrity of the effluent monitoring systems by requiring an update whenever a new process or operation introduces new hazardous materials or significant radioactive materials. This document must be reviewed annually even if there are no operational changes, and must be updated, as a minimum, every 3 years.
Date: March 8, 2000
Creator: Davis, W. E.
Object Type: Report
System: The UNT Digital Library
Seminole Sentinel (Seminole, Tex.), Vol. 93, No. 41, Ed. 1 Wednesday, March 8, 2000 (open access)

Seminole Sentinel (Seminole, Tex.), Vol. 93, No. 41, Ed. 1 Wednesday, March 8, 2000

Semiweekly newspaper from Seminole, Texas that includes local, state, and national news along with advertising.
Date: March 8, 2000
Creator: Dow, M. Gene & Fisher, David
Object Type: Newspaper
System: The Portal to Texas History
On the continuum-scale simulation of gravity-driven fingers with hysteretic Richards equation: Trucation error induced numerical artifacts (open access)

On the continuum-scale simulation of gravity-driven fingers with hysteretic Richards equation: Trucation error induced numerical artifacts

The authors consider the ability of the numerical solution of Richards equation to model gravity-driven fingers. Although gravity-driven fingers can be easily simulated using a partial downwind averaging method, they find the fingers are purely artificial, generated by the combined effects of truncation error induced oscillations and capillary hysteresis. Since Richards equation can only yield a monotonic solution for standard constitutive relations and constant flux boundary conditions, it is not the valid governing equation to model gravity-driven fingers, and therefore is also suspect for unsaturated flow in initially dry, highly nonlinear, and hysteretic media where these fingers occur. However, analysis of truncation error at the wetting front for the partial downwind method suggests the required mathematical behavior of a more comprehensive and physically based modeling approach for this region of parameter space.
Date: March 8, 2000
Creator: Eliassi, Mehdi & Glass Jr., Robert J.
Object Type: Article
System: The UNT Digital Library
The Wylie News (Wylie, Tex.), Vol. 53, No. 41, Ed. 1 Wednesday, March 8, 2000 (open access)

The Wylie News (Wylie, Tex.), Vol. 53, No. 41, Ed. 1 Wednesday, March 8, 2000

Weekly newspaper from Wylie, Texas that includes local, state and national news along with advertising.
Date: March 8, 2000
Creator: Engbrock, Chad B.
Object Type: Newspaper
System: The Portal to Texas History
Debt swapping as a tool for economic and social stabilization in Russia's closed nuclear cities (open access)

Debt swapping as a tool for economic and social stabilization in Russia's closed nuclear cities

The magnitude of Russian foreign debt, both official bilateral and commercial, compounded by collapse of the Russian economic system, is an obstacle in preventing the Russian Federation from effectively increasing the domestic priority of drawing down its nuclear weapons complex and providing a healthy, competitive environment to its nuclear cities. Debt-for-nature swaps, introduced in the early 1980s, provide debtor nations with a means of converting a portion of foreign debt into local currency, often at steep discounts, to use for purposes such as environmental protection that serve both a domestic and international need. This paper presents the debt-for-nature concept as a model for providing an infusion of funds to further U.S. and international nonproliferation objectives to help stabilize Russian closed city economic conditions through direct work on proliferation problems and remediation of the environment. A specific proposal is presented to demonstrate the utility and efficacy of the dept swap concept through initial collaboration with the city administration of Ozersk. The purpose of the proposal is to facilitate making Ozersk a safe, healthy competitive city, providing useful employment for its scientists and population and converting its superior infrastructure into productive activities.
Date: March 8, 2000
Creator: Fuller, JL & Leek, KM
Object Type: Report
System: The UNT Digital Library
Debt swapping as a tool for economic and social stabilization in Russia's closed nuclear cities (briefing paper) (open access)

Debt swapping as a tool for economic and social stabilization in Russia's closed nuclear cities (briefing paper)

The next great issue on the Russian landscape will be management of its foreign debt. In the near future the United States will be called upon to lead an international program of debt restructuring to assist Russia in overcoming the burden of its debt trap. With debt service obligations equal to 50{percent} of 1999 revenues, Russia has virtually no chance of sustaining a program of economic recovery without debt relief (Hardt, 1999). With some form of debt restructuring a foregone conclusion, Russia, the United States, and world community have a vital stake in searching for creative ways to transform the inevitability of debt restructuring into something of value and constructive to Russia and the problems it faces. This was the rationale behind debt-for-nature swaps which emerged in the early 1980s in Latin American and Eastern Europe as a means of relieving developing nations of their crippling foreign debt. Debt-for-nature swaps served both domestic and international needs by converting a portion of foreign debt, often at steep discounts, into local currency that was then used to fund programs to preserve the environment. The debt swap mechanism provides the prospect of getting something of real value where nothing is expected. The Pacific …
Date: March 8, 2000
Creator: Fuller, JL & Leek, KM
Object Type: Report
System: The UNT Digital Library
Pawhuska Journal-Capital (Pawhuska, Okla.), Vol. 90, No. 20, Ed. 1 Wednesday, March 8, 2000 (open access)

Pawhuska Journal-Capital (Pawhuska, Okla.), Vol. 90, No. 20, Ed. 1 Wednesday, March 8, 2000

Semiweekly newspaper from Pawhuska, Oklahoma that includes local, state, and national news along with advertising.
Date: March 8, 2000
Creator: Gann, Sherry
Object Type: Newspaper
System: The Gateway to Oklahoma History