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Temperature dependence of resistivity of thin film samples of chalcogenide glasses (open access)

Temperature dependence of resistivity of thin film samples of chalcogenide glasses

None
Date: October 1, 1975
Creator: Kulkarni, A. K.
System: The UNT Digital Library
Inductively coupled plasma--atomic emission spectrometry: trace elements in oil matrices (open access)

Inductively coupled plasma--atomic emission spectrometry: trace elements in oil matrices

The simultaneous determination of up to 20 trace elements in various oil matrices by inductively coupled plasma-atomic emission spectrometry is reported. The oil matrices investigated were lubricating oils (for wear metals), fuel oil, centrifuged coal liquefaction product, crude soybean oil, and commercial edible oils. The samples were diluted with appropriate organic solvents and injected into the plasma as an aerosol generated by a pneumatic nebulization technique. Detection limits of the 28 elements studied ranged from 0.0006 to 9 ..mu..g/g with the majority falling in the 0.01 to 0.1 ..mu..g/g range. Analytical calibration curves were linear over at least two orders of magnitude and for some elements this linearity extended over 4.5 orders of magnitude. Relevant data on precision and accuracy are included. Because metals often occur as particles in lubricating oil and coal liquefaction products, the effect of particles on the analytical results was examined. Wear metal particles in used oil did not appear to affect the analytical results. However, incomplete recovery relative to organometallic reference solutions was obtained for iron particles with a nominal mean diameter of 3.0 ..mu..m suspended in oil. It was shown that the following factors contributed to incomplete recovery for the particles: settling of the …
Date: December 1, 1977
Creator: Peterson, C. A.
System: The UNT Digital Library
Analytical applications of resins containing amide and polyamine functional groups (open access)

Analytical applications of resins containing amide and polyamine functional groups

A dibutyl amide resin is used for the separation of uranium(VI), thorium(IV), and zirconium(IV) from each other and several other metal ions. Uranium(VI) and thorium(IV) are determined in the presence of large excesses of foreign metal ions and anions. A practical application of the amide resin is studied by determining uranium in low grade uranium ores. The amide resin is also used for the selective concentration of gold(III) from sea water.
Date: December 1, 1977
Creator: Orf, G. M.
System: The UNT Digital Library
A Method for Estimating the Heat of Formation and Free Energy of Formation of Inorganic Compounds (open access)

A Method for Estimating the Heat of Formation and Free Energy of Formation of Inorganic Compounds

None
Date: August 1, 1962
Creator: Wilcox, D. E.
System: The UNT Digital Library
Heavy-Ion Elastic Scattering (open access)

Heavy-Ion Elastic Scattering

The elastic scattering of C/sup 12/ ions from Ar, Fe, Ni, Ag/sup 107/ In, and Ta was measured as a function of angle, at a laboratory-system energy of 124.5 Mev with the Berkeley heavy-ion linear accelerator. The experimental equipment and techniques are discussed. The angular distributions show the same general behavior as previous heavy-ion elastic scattering experiments. The experimental data were analyzed with the semiclassical Blair model as modified by McIntyre. Very good agreement with experiment was obtained. The measurements were taken with 1% statistics in order to study the structure of the angular distributions in greater detail, because only by fitting the details in the structure was it possible to obtdin unambiguous sets of parameters. The parameters indicated a nuclear radius of 1.45A/sup 1/3/ x 10/sup -13/ cm, and a nearly constant surface thick ness of 1.6 x 10/sup -13/ cm. Total reaction cross sections were obtained. A rainbow-model analysis by Goldman of the data is given. Existing alpha - and heavy-ion scattering data were analyzed with the McIntyre model and compared with previous optical-model analyses of the same data. It was found that, by independent analysis, the two models give the same imaginary phase shifts for all partial …
Date: April 17, 1961
Creator: Alster, Jonas
System: The UNT Digital Library
Dislocation morphology in deformed and irradiated niobium. [Neutron irradiation] (open access)

Dislocation morphology in deformed and irradiated niobium. [Neutron irradiation]

Niobium foils of moderate purity were examined for the morphology of dislocations or defect clusters in the deformed or neutron-irradiated state by transmission electron microscopy. New evidence has been found for the dissociation of screw dislocations into partials on the (211) slip plane according to the Crussard mechanism: (a/2) (111) ..-->.. (a/3) (111) + (a/6) (111).
Date: June 1, 1977
Creator: Chang, C. P.
System: The UNT Digital Library
Lanthanide extraction with 2,5-dimethyl-2-hydroxyhexanoic acid (open access)

Lanthanide extraction with 2,5-dimethyl-2-hydroxyhexanoic acid

This research is concerned with the solvent extraction into chloroform of the lanthanides, using 2,5-dimethyl-2-hydroxyhexanoic acid (DMHHA). This acid is the first ..cap alpha..-hydroxy aliphatic acid to be studied as an extracting agent for the lanthanides. The chloroform-water DMHHA partition constant was determined to be 1.0 (at 0.1 M ionic strength and 25/sup 0/C). The acid dimerizes in chloroform with a constant of 56. The light lanthanides can be extracted into chloroform by forming complexes with the DMHHA anions. The extracted metal species is highly aggregated. This extraction has a solubility limit which increases with the addition of unionized acid. The resultant extract is also highly aggregated. At unionized acid-to-metal ratios greater than one, extractions first occur followed by the slow precipitation of the lanthanide. At the tracer level, neodymium is extracted primarily as NdA/sub 3/(HA)/sub 5/ and (NdA/sub 3/)/sub 2/(HA)/sub q/. Very small amounts of (NdA/sub 3/)/sub 2/ and other metal aggregates are also present. The heavy lanthanides do not extract from solutions of DMHHA and its potassium salt, but form aqueous emulsions and precipitates. In the presence of the organic soluble tetrabutylammonium ion the heavy lanthanides can be extracted, presumably as ion pairs. The stability constants of the …
Date: December 1, 1977
Creator: Miller, J. H.
System: The UNT Digital Library
Child-Centered Play Therapy (CCPT) with Latina/o Children Exhibiting School Behavior Problems: Comparative Effects of Delivery by Spanish-Speaking and English-Speaking Counselors (open access)

Child-Centered Play Therapy (CCPT) with Latina/o Children Exhibiting School Behavior Problems: Comparative Effects of Delivery by Spanish-Speaking and English-Speaking Counselors

The shortage of bilingual counselors is one barrier to young Latina/o children receiving mental health services. Child-centered play therapy (CCPT) is a developmentally responsive intervention based on the premise that play is children's natural means of communication across cultures. This randomized controlled study examined the effects of CCPT with young Spanish-speaking Latina/o children exhibiting clinical levels of school behavior problems. Participants were 57 pre-K to kindergarten Latina/o children (72% male; mean age = 4.0) randomly assigned to three treatment groups: CCPT with Spanish-speaking, bilingual counselors; CCPT with English-speaking, monolingual counselors; or active control (bilingual mentoring). Monolingual counselors participated in cultural competency training and supervision with bilingual counselors and supervisors. According to independent observers and teachers blinded to children's group assignment, both the bilingual CCPT group and the monolingual CCPT group demonstrated moderate treatment effects over bilingual mentoring, yet between-group differences were not statistically significant. Analysis of within-group change over time indicated that children in both CCPT interventions demonstrated statistically significant improvement, while the mentoring group did not. The percentage of children in each treatment group who improved from clinical to normal behavioral functioning suggests the clinical significance of the findings: 80% bilingual CCPT, 70% monolingual CCPT, 15% bilingual mentoring. Overall, …
Date: December 2017
Creator: Barcenas Jaimez, Gustavo
System: The UNT Digital Library
Human-Machine Interface Using Facial Gesture Recognition (open access)

Human-Machine Interface Using Facial Gesture Recognition

This Master thesis proposes a human-computer interface for individual with limited hand movements that incorporate the use of facial gesture as a means of communication. The system recognizes faces and extracts facial gestures to map them into Morse code that would be translated in English in real time. The system is implemented on a MACBOOK computer using Python software, OpenCV library, and Dlib library. The system is tested by 6 students. Five of the testers were not familiar with Morse code. They performed the experiments in an average of 90 seconds. One of the tester was familiar with Morse code and performed the experiment in 53 seconds. It is concluded that errors occurred due to variations in features of the testers, lighting conditions, and unfamiliarity with the system. Implementing an auto correction and auto prediction system will decrease typing time considerably and make the system more robust.
Date: December 2017
Creator: Toure, Zikra
System: The UNT Digital Library
Exploring the Process of Developing a Glocally Focused Art Curriculum for Two Communities (open access)

Exploring the Process of Developing a Glocally Focused Art Curriculum for Two Communities

The world is becoming progressively interconnected through technology, politics, culture, economics, and education. As educators we strive to provide instruction that prepares students to become active members of both their local and global communities. This dissertation presents one possible avenue for engaging students with art and multifaceted ideas about culture, community, and politics as it explores the possibilities for creating a community-based, art education curriculum that seeks a merger of global and local, or "glocal" thinking. Through curriculum action research, I explored the process of writing site-specific curriculum that focuses on publicly available, local works of art and encourages a connection between global experiences and local application. I have completed this research for two communities, one in Ohio and one in Texas, and investigated the similarities and differences that exist in the process and resulting curriculum for each location. Through textual analysis, interviews, curriculum writing, and personal reflections, I identified five essential components of a community-based, glocal art education curriculum: flexibility, authenticity, connectedness, glocal understandings, and publicly available art. Additionally, I developed a template for writing glocally focused, community-based art education curriculum and produced completed curricular units for each of the communities. Finally, I have made suggestions for the future …
Date: December 2017
Creator: Hartman, Jennifer D
System: The UNT Digital Library
When Race Matters: The Influence of Race on Case Clearances in Capital vs. Non-Capital Homicides in Texas (open access)

When Race Matters: The Influence of Race on Case Clearances in Capital vs. Non-Capital Homicides in Texas

Texas leads the nation in the number of executions carried out since capital punishment was reinstated in 1976. Race was a key factor in the 1972 moratorium, and though the Supreme Court allowed for its return under new statutes, race continues to plague the capital punishment legal system. In this study, I examine the influence of race on case clearances in capital and non-capital homicides in Texas, using the extra-legal and non-discretionary theories from existing clearance literature. I find that race influences the probability of cases being cleared in non-capital cases but has no statistically significant effect in clearing capital cases.
Date: December 2017
Creator: Samaniego, Rebekah
System: The UNT Digital Library
Child-Centered Play Therapy with Children Affected by Adverse Childhood Experiences: A Single Case Design (open access)

Child-Centered Play Therapy with Children Affected by Adverse Childhood Experiences: A Single Case Design

Child centered play therapy (CCPT) is a therapeutic intervention that provides the environment for children to work through and heal from difficult experiences through expression of play and therapeutic relationship. It has been demonstrated effective with multiple types of disruptive behaviors. I conducted single-case research to explore CCPT's influence on children who had four or more adverse childhood experiences (ACEs) and provided analysis of data collected from one assessment administered weekly and one assessment at pre-, mid-, and post-intervention: the Strength and Difficulties Questionnaire and the Trauma Symptoms Checklist for Young Children. The two participants (one 8-year-old White American male and one 9-year-old White American female) demonstrated significant improvement in total difficulties and prosocial behaviors. The study revealed potential therapeutic benefits for utilizing CCPT with children who had four or more ACEs. Encompassed in discussion of study results are implications for practice, suggestions for future research, and limitations.
Date: December 2017
Creator: Haas, Sara C
System: The UNT Digital Library
Mediational Pathways between High School Extracurricular Participation and Young Adult Educational Attainment: A Structural Equation Analysis (open access)

Mediational Pathways between High School Extracurricular Participation and Young Adult Educational Attainment: A Structural Equation Analysis

Little is known about the mechanisms by which extracurricular participation in high school influences educational attainment in young adulthood. Also limited is an understanding of the different types of extracurricular participation and how various activities may manifest within the relationship. The purpose of this study was to examine the link between high school extracurricular participation and educational attainment, with social capital, parental expectations, and academic achievement presented as mediators. Additionally, the present study will explore socioeconomic differences in the proposed relationships. The sample consisted of 5,239 ninth through twelfth graders from the National Longitudinal Study of Adolescent Health (Add Health). Structural equation modeling (SEM) and multiple-group SEM were used to test pathways. Extracurricular participation was categorized into sports participation, non-sport participation, mixed participation (including both sport and non-sport), and no participation. Social capital, a latent factor, was measured by the latent variables of family and school capital. Various indicators of family closeness and inclusion of school culture from survey items operationalize social capital. Parental expectations, another latent factor, was measured by one survey indicator using the question of how disappointed would your resident father and mother be if you did not graduate from college. Academic achievement was measured by grade …
Date: December 2017
Creator: Long, Roxanne
System: The UNT Digital Library
Who is Really in Charge Here: An Exploration of the Formation and Empowerment of Opinion Leaders in a Reddit Gaming Community (open access)

Who is Really in Charge Here: An Exploration of the Formation and Empowerment of Opinion Leaders in a Reddit Gaming Community

In an attempt to shed light on the further sophistication of opinion leadership in online communities, this study examined the forces and structures that affect their formation in the League of Legends subreddit. By investigating what users thought about the various types of individuals with which the communicate, the researcher hoped to begin to understand and record how those forces work bother on this particular subreddit and in mass media beyond. Opinion leadership continues to be an integral force in deciding what information is consumed by a public and under what frames and agendas it is contextualized. If researchers can operationalize formal definitions for the influences and structures that occur online, they can better navigate the deep waters that are global communication on the internet.
Date: December 2017
Creator: Carter, Clinton Chase
System: The UNT Digital Library
An Assessment of Extant Euphonium Methodologies for Developing and Performing in the Upper Register (open access)

An Assessment of Extant Euphonium Methodologies for Developing and Performing in the Upper Register

This dissertation presents a categorization of existing methodologies of upper register development for euphoniumists with evaluation of effectiveness and current use of these methodologies. The purpose of this study is to provide euphonium musicians as well as educators with essential references and guides to applicable methods for developing the upper register more effectively with greater efficacy. The assessments of current methodologies include three steps: categorization, summarization, and evaluation. To support the significance why it could be more beneficial than the methodology alone, the dissertation will include the examination of the aspect of biomechanics and ergonomics, suggestions, and discussion of particular issues of the upper register.
Date: December 2017
Creator: Chou, Wei Chien
System: The UNT Digital Library
Stability of Myosin Subfragment-2 Modulates the Force Produced by Acto-Myosin Interaction of Striated Muscle (open access)

Stability of Myosin Subfragment-2 Modulates the Force Produced by Acto-Myosin Interaction of Striated Muscle

Myosin subfragment-2 (S2) is a coiled coil linker between myosin subfragment-1 and light meromyosin (LMM). This dissertation examines whether the myosin S2 coiled coil could regulate the amount of myosin S1 heads available to bind actin thin filaments by modulating the stability of its coiled coil. A stable myosin S2 coiled coil would have less active myosin S1 heads compared to a more flexible myosin S2 coiled coil, thus causing increased force production through acto-myosin interaction. The stability of the myosin S2 coiled coil was modulated by the binding of a natural myosin S2 binding protein, myosin binding protein C (MyBPC), and synthetic myosin S2 binding proteins, stabilizer and destabilizer peptide, to myosin S2. Competitive enzyme linked immunosorbent assay (cELISA) experiments revealed the cross specificity and high binding affinity of the synthetic peptides to the myosin S2 of human cardiac and rabbit skeletal origins. Gravitational force spectroscopy (GFS) was performed to test the stability of myosin S2 coiled coil in the presence of these myosin S2 binding proteins. GFS experiments demonstrated the stabilization of the myosin S2 coiled coil by the binding of MyBPC and stabilizer peptide to myosin S2, while the binding of destabilizer peptide to the same resulted …
Date: December 2017
Creator: Singh, Rohit Rajendraprasad
System: The UNT Digital Library
TRANSPORT REACTIONS OF THORIUM OXYDIIODIDE. (open access)

TRANSPORT REACTIONS OF THORIUM OXYDIIODIDE.

None
Date: January 1, 1969
Creator: Adolphson, D.G.
System: The UNT Digital Library
Anomalous Radial Plasma Losses in a Q-Machine With Mirror Magnetic Fields. (open access)

Anomalous Radial Plasma Losses in a Q-Machine With Mirror Magnetic Fields.

None
Date: April 1972
Creator: Searing, Richard Manor
System: The UNT Digital Library
DESIGN MODEL FOR THE DYNAMIC ADSORPTION OF URANIUM HEXAFLUORIDE ON FIXED BEDS OF SODIUM FLUORIDE. (open access)

DESIGN MODEL FOR THE DYNAMIC ADSORPTION OF URANIUM HEXAFLUORIDE ON FIXED BEDS OF SODIUM FLUORIDE.

None
Date: December 1, 1968
Creator: Stephenson, M.J.
System: The UNT Digital Library
Magnetic excitations above the critical temperature (open access)

Magnetic excitations above the critical temperature

None
Date: October 1, 1975
Creator: Swanson, P. A.
System: The UNT Digital Library
Investigation of high energy runaway electron confinement in the Oak Ridge tokamak (open access)

Investigation of high energy runaway electron confinement in the Oak Ridge tokamak

High energy runaway electrons in the Oak Ridge tokamak ORMAK have been investigated through measurement of the bremsstrahlung produced when these electrons leave the discharge and strike the limiting aperture of the torus. The experimental results have been interpreted in terms of a classical single-particle model appropriate for collisionless particles in a tokamak, and it has been found that most of the confinement properties of high energy runaways in ORMAK can be understood on this basis. An experiment designed to directly test this model has disclosed an anomalous transport which has been described by a runaway diffusion coefficient D approximately 10/sup 2/ to 10/sup 4/ cm/sup 2//sec appropriate for runaways near the outside of the plasma. A discussion of the possible mechanisms for this anomalous transport is given.
Date: November 1, 1977
Creator: Zweben, S. J.
System: The UNT Digital Library
Low-Energy, High-Resolution, Variable Angle Electron Impact Spectroscopy. (open access)

Low-Energy, High-Resolution, Variable Angle Electron Impact Spectroscopy.

None
Date: January 1, 1969
Creator: Rice, J. K.
System: The UNT Digital Library
DEFORMED POTENTIAL MANY-PARTICLE THEORY. (open access)

DEFORMED POTENTIAL MANY-PARTICLE THEORY.

None
Date: January 1, 1968
Creator: Draayer, J.P.
System: The UNT Digital Library
ELECTRON TRANSFER REACTIONS OF FERROCENE. (open access)

ELECTRON TRANSFER REACTIONS OF FERROCENE.

None
Date: January 1, 1971
Creator: Pladziewicz, J R
System: The UNT Digital Library