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NMR study of 2-ethylhexyllithium aggregate and 2- ethylhexyllithium/lithium 2-ethyl-1-hexoxide mixed aggregates.

Description: A 1H, 13C, and 6Li NMR study of 2-ethylhexyllithium showed that 2- ethylhexyllithium exists solely as a hexamer in cyclopentane solution over the temperature range from 25 to -65 °C. Furthermore, 2-ethylhexyllithium and lithium 2- ethyl-1-hexoxide were shown to form mixed aggregates when the alkoxide was formed in situ by reacting 2-ethylhexyllithium with 2-ethyl-1-hexanol. A multinuclear, variable temperature NMR study of a sample with an O:Li ratio of 0.2 led to the identification of at least… more
Date: December 2001
Creator: Petros, Robby A.
Partner: UNT Libraries

Alexander Johnson's Ni' Concerto (1994) - Concerto no. 1 for Piano and Orchestra: a Discussion of Influences from Africa, Eastern and Western Europe

Description: In the new generation of artists emerging in South Africa, Alexander Johnson is considered the most prolific young composer of his day. In a recent review in the Pretoria News, Johnson has been praised by eminent critic Paul Boekkooi as a composer who has “an ear for the exotic and knows exactly how to bring it off....” He continued by noting that his music is “mentally engrossing, pleasurable to the senses and seems refreshingly free from dogmatic formulas." Johnson writes for musicians and th… more
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Date: August 2001
Creator: Malan, Petronel
Partner: UNT Libraries
open access

An NMR study of 2-ethyl-1-butyllithium and of 2-ethyl-1-butyllithium/lithium 2-ethyl-1-butoxide mixed aggregates

Description: A 1H, 13C, and 6Li NMR study of 2-ethyl-1-butyllithium indicated that 2-ethyl-1-butyllithium exists only as a hexameric aggregate over the entire temperature range of 25 to - 92.1 ° C in cyclopentane. Reacting 2-ethyl-1-butyllithium with 2-ethyl-1-butanol resulted in alkyllithium/lithium alkoxide mixed aggregates, apparently of the form Ra(RO)bLia+b. A multinuclear, variable temperature NMR study of samples with O:Li ratios of 0.2 and 0.4 showed, in addition to the alkyllithium, the formation o… more
Date: May 2001
Creator: Ferreira, Aluisio V. C.
Partner: UNT Libraries
open access

Symphony No. 1

Description: Symphony No. 1 is an orchestral composition for twenty-four instrumental groups without percussion instruments. It was composed with Algorithmic Composition System software, which gives driving forces for composition to the composer through the diverse compositional methods largely based on physical phenomena. The symphony consists of three movements. It lasts about sixteen minutes and twenty-six seconds--five minutes and twenty-two seconds for the first movement, five minutes and forty seconds… more
Date: May 2001
Creator: Choi, Jongmoon
Partner: UNT Libraries
open access

A Search for new physics in photon-lepton events in proton-antiproton collisions at {radical} s = 1.8 TeV

Description: We present the results of a search in p{bar p} collisions at {radical}s = 1.8 TeV for anomalous production of events containing a photon with large transverse energy and a lepton (e or {mu}) with large transverse energy, using 86 pb{sup -1} of data collected at the Collider Detector at Fermilab during the 1994-95 collider run at the Fermilab Tevatron. The presence of large missing transverse energy (E{sub T}), additional photons, or additional leptons in these events is also analyzed. The resul… more
Date: April 30, 2001
Creator: Berryhill, J. W.
Partner: UNT Libraries Government Documents Department
open access

Electroproduction of Photons and of Pawns on the Proton in Quadrimoment of Transfer Q2=1.0GeV2. Measure Cross Sections and Extraction of Polarizabilities Generalities; Electroproduction de Photons et de Pions sur le Proton au Quadrimoment de Transfert Q2=1.0GeV2. Mesure des Sections Efficaces et Extraction des Polarisabilites Generalisees

Description: In hadronic physics, the nucleon structure and the quarks confinement are still topical issues. The neutral pion electroproduction and virtual Compton scattering (VCS) reactions allow us to access new observables that describe this structure. This work is focused on the VCS experiment performed at Jefferson Lab in 1998.
Date: November 6, 2001
Creator: Laveissiere, Geraud
Partner: UNT Libraries Government Documents Department
open access

Substitution chemistry of the cobalt complexes RCCo3(CO)9 (R = H, CHO) with the diphosphine ligand: 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd). Syntheses, X-ray structures and reactivity.

Description: The reaction between the tetrahedrane cluster RCCo3(CO)9{R = CHO (1), H (3)} and the redox-active diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3- dione (bpcd) leads to the replacement of two CO groups and formation of RCCo3(CO)7(bpcd) {R = CHO (2), H (4)}. Clusters 2 and 4 are thermally unstable and readily transform into the new P-C bond cleavage cluster 5. All three clusters 2, 4, and 5 have been isolated and fully characterized in solution by IR and 31P NMR spectroscopy. VT … more
Date: December 2001
Creator: Liu, Jie
Partner: UNT Libraries

Mechanisms of Methoxide Ion Substitution and Acid- Catalyzed Z/E Isomerization of N-Methoxyimines

Description: The second order rate constants for nucleophilic substitution by methoxide of (Z)- and (E)-O-methylbenzohydroximoyl fluorides [C6H4C(F)=NOCH3] with various substituents on the phenyl ring [p-OCH3 (1h, 2h), p-CH3 (1g, 2g), p-Cl (1f, 2f), p-H (1e, 2e), (3,5)-bis-CF3 (1i, 2i)] in 90:10 DMSO:MeOH have been measured. A Hammett plot of these rate constants vs σ values gave positive ρ values of 2.95 (Z isomer) and 3.29 (E isomer). Comparison of these rates with methoxide substitution rates for Ometh… more
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Date: December 2001
Creator: Dolliver, Debra D.
Partner: UNT Libraries
open access

Spatial and Temporal Patterns of Areal and Volumetric Phytoplankton Productivity of Lake Texoma

Description: Phytoplankton productivity of Lake Texoma was measured for one year from August 1999 to August 2000 for four stations, using the oxygen change method and laboratory incubation. Mean values of the photosynthetic parameters, PBmax and alphaB ranged from 4.86 to 46.39 mg O2.mg Chl-1.hr-1 for PBmax and 20.06 to 98.96 mg O2.mg Chl-1.E-1.m2 for alphaB. These values were in the range to be expected for a highly turbid, temperate reservoir. Estimated gross annual areal productivity ranged from 594 g… more
Date: August 2001
Creator: Baugher, Tessy
Partner: UNT Libraries

The Effects of a Conflicting Instruction on a Fr 5 Performance

Description: The purpose of this experiment was to evaluate the effects of a conflicting instruction on FR-5 performances by an ABABC design. After all four college students were consistently pressing 1-5-3 followed by sound-clips, the schedule value changed to FR-5 (A). Then they were presented with the written instruction "Press 426" (B) in addition to the previous condition. In the last condition (C), 1-5-3 responses were then scheduled for extinction in three participants and the reinforcer was changed … more
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Date: May 2001
Creator: Koremura, Yuka
Partner: UNT Libraries

Layered Double Hydroxides and the Origins of Life on Earth

Description: A brief introduction to the current state of research in the Origins of Life field is given in Part I of this work. Part II covers original research performed by the author and co-workers. Layered Double Hydroxide (LDH) systems are anion-exchanging clays that have the general formula M(II)xM(III)(OH)(2x+2)Y, where M(II) and M(III) are any divalent and trivalent metals, respectively. Y can be nearly any anion, although modern naturally occuring LDH systems incorporate carbonate (CO32-), chloride… more
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Date: May 2001
Creator: Brister, Brian
Partner: UNT Libraries
open access

Focus on NIF May 2001

Description: The National Ignition Facility, a stadium-size, 192-beam laser, is an essential tool for maintaining the safety and reliability of our nuclear weapons, harnessing fusion energy for future generations, and unlocking the origins of the universe. In the FY2001 Energy and Water Appropriations Act (FPN00-48), Congress appropriated $199.1 million for the continued construction of NIF. Immediately, $130 million became available. After March 31, 2001, $69.1 million was to be made available only after D… more
Date: May 1, 2001
Creator: Warner, B
Partner: UNT Libraries Government Documents Department
open access

Rhapsody for Piano and Small Orchestra

Description: Rhapsody for Piano and Small Orchestra is a one-movement composition in a concerto fashion for seventeen players, and is about nine minutes in duration. The overall form of this work is A B C D E D1 C1 B1 A1. This work contains various hidden compositional devices such as the golden section principle and a palindrome structure. These devices are applied not only to the structure of the work, but also to the pitch related and rhythm-related matters. Also, certain melodic and rhythmic cells are … more
Date: December 2001
Creator: Ahn-Kim, Yong Hee
Partner: UNT Libraries

Characterization of Moraxella bovis Aspartate Transcarbamoylase

Description: Aspartate transcarbamoylase (ATCase) catalyzes the first committed step in the pyrimidine biosynthetic pathway. Bacterial ATCases have been divided into three classes, class A, B, and C, based on their molecular weight, holoenzyme architecture, and enzyme kinetics. Moraxella bovis is a fastidious organism, the etiologic agent of infectious bovine keratoconjunctivitis (IBK). The M. bovis ATCase was purified and characterized for the first time. It is a class A enzyme with a molecular mass of 4… more
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Date: December 2001
Creator: Hooshdaran, Sahar
Partner: UNT Libraries
open access

The Impact of Poverty on Comparable Improvement Ranking for Elementary Campuses in Texas

Description: The problem was to determine how comparable is comparable improvement for campuses in Texas. An alternative strategy for determining comparable improvement was developed using 2000 comparable improvement data provided by the Texas Education Agency for 2,403 elementary campuses. Comparable improvement is a measure that shows how student performance has changed from one year to the next and then compares that growth to 40 schools that are demographically most similar to the target school. Instead… more
Date: December 2001
Creator: Holland, Vicki Gay
Partner: UNT Libraries
open access

A Collapsing Result Using the Axiom of Determinancy and the Theory of Possible Cofinalities

Description: Assuming the axiom of determinacy, we give a new proof of the strong partition relation on ω1. Further, we present a streamlined proof that J<λ+(a) (the ideal of sets which force cof Π α < λ) is generated from J<λ+(a) by adding a singleton. Combining these results with a polarized partition relation on ω1
Date: May 2001
Creator: May, Russell J.
Partner: UNT Libraries
open access

Thermochemical Study of Crystalline Solutes Dissolved in Ternary Hydrogen-Bonding Solvent Mixtures

Description: The purpose of this dissertation is to investigate the thermochemical properties of nonelectrolyte solutes dissolved in ternary solvent mixtures, and to develop mathematical expressions for predicting and describing behavior in the solvent mixtures. Forty-five ternary solvent systems were studied containing an ether (Methyl tert-butyl ether, Dibutyl ether, or 1,4-Dioxane), an alcohol (1-Propanol, 2-Propanol, 1-Butanol, 2-Butanol, or 2-Methyl-1-propanol), and an alkane (Cyclohexane, Heptane, or… more
Date: May 2001
Creator: Pribyla, Karen J.
Partner: UNT Libraries
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Predictors of Use and Outcomes of Youth and Family Centers

Description: This study analyzed data from Dallas Public Schools and Dallas Youth and Family Centers (YFCs) to explore variables associated with referrals to and utilization of Youth and Family Centers. Data from students enrolled in third, eighth or tenth grade during the 1996-1997, 1997-1998 and 1998-1999 school years were analyzed to determine the reasons for YFC referral and utilization, and to compare standardized test scores and attendance. Of the 6956 students in third, eighth and tenth grades initi… more
Date: May 2001
Creator: Scharff, Karen
Partner: UNT Libraries
open access

Media Influence on Executive Police Decision-Making: A Case Study of Police and Media Interaction During the Oklahoma City Bombing Investigation and Trials

Description: Because media influence public opinion, it is often surmised that media also influence the decisions of police executives. This exploratory case study examined the relationship between police and media during the Oklahoma City bombing investigation and subsequent trials of Timothy McVeigh and Terry Nichols. Findings indicate that media influence police executive decisions when police and media interact closely. It was found that during the Oklahoma City bombing investigation and trials, police… more
Date: May 2001
Creator: Bellew, Steven S.
Partner: UNT Libraries
open access

Parent, Student, and Faculty Satisfaction With and Support of Campus Laboratory School Programs

Description: The primary purpose of the study was to investigate stakeholders' opinions concerning campus laboratory school program quality in three areas: (1) quality of teacher education, (2) research, and (3) childcare. There were 653 participants in the study: 246 parents whose children were enrolled in laboratory schools, 200 pre-service students who were taking early childhood or child development classes, and 207 faculty who were associated with campus laboratory schools. The study participants came … more
Date: May 2001
Creator: Seo, Hyunnam
Partner: UNT Libraries
open access

Mechanics of Metals with Phase Changes

Description: New experimental data is presented on some exotic metals that exhibit phase changes at cryogenic temperatures. The types of phase changes that were detected in the specific heat data range from martensitic (diffusion less) transitions to superconducting transitions. In addition, the charge density wave (CDW) state in uranium metal was detected in the specific heat. Specific-heat measurements were made in zero-magnetic field using an apparatus capable of obtaining temperatures as low as 0.4 K. C… more
Date: January 1, 2001
Creator: Lashley, J.C.
Partner: UNT Libraries Government Documents Department
open access

Geographical and Temporal Dynamics of Chaetocnema Pulicaria Populations and Their Role in Stewart's Disease of Corn in Iowa

Description: This thesis is organized into five chapters. Chapter 1 is the introduction and justification, chapters 2 and 3 are journal papers, chapter 4 is a preliminary analysis of winter environmental variables and their use in forecasting for Stewart's disease of corn, and chapter 5 is general conclusions and discussion. References can be found at the end of each chapter, except chapter 5 and are specific to that chapter.
Date: May 1, 2001
Creator: Esker, Paul David
Partner: UNT Libraries Government Documents Department
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