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Accomplished Teachers' Instructional Decisions About Shakespeare
Teachers' decisions are a powerful influence on student learning and it is important to fully document accomplished teachers' instructional decisions, as well as to investigate possible influences on those decisions. Shakespearean dramas are central to high school curricula across the U.S. and pose particular instructional challenges, therefore teachers' decisions about teaching these texts are of particular interest. There is limited empirical research, however, about these instructional decisions. Thus, the purpose of this study was to describe how four accomplished high school English teachers working on a single campus make instructional decisions about teaching a Shakespearean play. Specifically, research questions addressed teachers' decisions regarding the teaching of a Shakespearean play and various influences on those decisions (self-reports and inferences from the data). Case study methodology was used, including an inductive analysis of individual teacher interviews, classroom observations, focus group, instructional artifacts, and researcher's journal. The findings revealed that instructional activities described by these teachers addressed support for meaning-making during four stages of reading instruction: (a) before, during, and after; (b) before; (c) during; and (d) after. Comparison of these cases suggests that, although each teacher brings personal preferences and unique background knowledge to her instructional decisions, all make decisions to promote …
Date:
May 2013
Creator:
Parris, Sheri Rene’
System:
The UNT Digital Library
Accreditation Facilitation Projects: Supporting High Quality Early Childhood Education and Care
High-quality early childhood education and care (ECEC) are linked to positive developmental outcomes for children. Systems have been created to define, measure and promote high-quality ECEC. National accreditation status is deemed the gold standard of a high-quality program, yet many centers are unable to achieve this without assistance. With the help of Accreditation Facilitation Projects (AFPs), many low-income centers are able to achieve accreditation. Centers collaborating with an AFP reap many benefits including financial support, ongoing training and mentoring, and guidance through the accreditation process. AFPs invest greatly in the centers they collaborate with and the longer the center takes to achieve accreditation, the more resources an AFP must expend. The purposes of this study were to understand if the educational level of center director, the total enrollment of a center, or the percentage of children receiving government subsidies could predict the time it takes for a center to complete the accreditation process while receiving assistance from an AFP, and to determine if there are differences in attitudes about program accreditation between center directors and early learning specialists who serve as accreditation mentors to the directors. Findings revealed that a) the higher educational level of program directors is associated with …
Date:
May 2013
Creator:
Reinke, Stephanie L.
System:
The UNT Digital Library
Adapting on the Plains: the United States Army's Evolution of Mobile Warfare in Texas, 1848-1859
The Army, despite having been vexed for a century on how to effectively fight the Plains Indians, ultimately defeated them only a decade after the Civil War. This thesis will bring to the forefront those individuals who adapted fighting techniques and ultimately achieved victories on the Texas frontier before the Civil War. The majority of these victories came as a result of mounted warfare under the direction of lower ranking officers in control of smaller forces. The tactic of fighting Indians from horseback was shown to be effective by the Rangers and later emulated by the Army.
Date:
May 2013
Creator:
Buchy, Mark B.
System:
The UNT Digital Library
Aging Is a Determinant in Anoxia Stress Tolerance in Caenorhabditis Elegans
Oxygen availability is critical for survival for most organisms. The nematode, C. elegans, has been useful for studying genetic regulation of anoxia tolerance due to the oxygen deprivation response mechanisms shared with other metazoans. Studies examining long-term anoxia (72h, LTA) tolerance have only been conducted at adult day 1. To investigate the effect of aging on anoxia tolerance wild-type and mutant strains were exposed to LTA between adult day 1 and day 9. Wild-type isolates and daf-16(mu86) (FOXO transcription factor regulated by insulin-signaling) and aak-2(gt33) (catalytic subunit of AMP-activated protein kinase) strains were anoxia sensitive at day 1 and displayed increased LTA tolerance with aging correlated with reproductive senescence followed by a decline in survivorhsip through day 9. The daf-2(e1370) (insulin receptor homologue of C. elegans), glp-1(e2141) (a lin-12/Notch receptor) and fog-2(q71) (required for spermatogenesis) strains were LTA-tolerant through day 5. I conclude that aging influences LTA-tolerance in a strain- and age-dependent manner. In addition to being LTA-tolerant the daf-2(e1370) and glp-1(e2141) strains have a longevity phenotype that is suppressed by loss of kri-1 or daf-12. While loss of kri-1 did not suppress the LTA-tolerant phenotype of glp-1(e2141) at day 1 the portion of impaired survivors increased at day 3 …
Date:
May 2013
Creator:
Goy, Jo M.
System:
The UNT Digital Library
An Analysis of Pitch Organization in Villa-lobos's Rudepoêma
Heitor Villa-Lobos (1887-1959) stands central to the music history of the Brazilian twentieth century. His music represents a synthesis of the European art influences he absorbed and his quest to find a true Brazilian identity, which was not rooted in the deliberate imitation of Brazilian folk elements, but rather in the natural assimilation of them in his compositional style. His early compositions embody strong post-romantic, impressionistic tendencies, especially in regard to their harmonies and use of tone color, whereas the works from the 1920's and onwards show Villa-Lobos increasingly asserting his unusual and strong voice. Villa-Lobos's large-scale composition for piano, Rudepoêma, was composed between 1921 and 1926, and stands as one of the most significant contributions to the Latin-American piano literature. Despite of its importance in Villa-Lobos's oeuvre, it has largely eluded analytical attention. Discourse on Villa-Lobos is often marked by a somewhat one-dimensional approach that identifies the folk and rhythmic elements as the most important characteristics of his compositional style, and displays a certain reticence with regard to in-depth analysis of other parameters of his works. This study redresses the imbalance in the general approach to analytical assessment of Villa-Lobos's oeuvre by illustrating that pitch organization plays an indispensable …
Date:
May 2013
Creator:
Kruger, Esthea
System:
The UNT Digital Library
Analytical Model of Cold-formed Steel Framed Shear Wall with Steel Sheet and Wood-based Sheathing
The cold-formed steel framed shear walls with steel sheets and wood-based sheathing are both code approved lateral force resisting system in light-framed construction. In the United States, the current design approach for cold-formed steel shear walls is capacity-based and developed from full-scale tests. The available design provisions provide nominal shear strength for only limited wall configurations. This research focused on the development of analytical models of cold-formed steel framed shear walls with steel sheet and wood-based sheathing to predict the nominal shear strength of the walls at their ultimate capacity level. Effective strip model was developed to predict the nominal shear strength of cold-formed steel framed steel sheet shear walls. The proposed design approach is based on a tension field action of the sheathing, shear capacity of sheathing-to-framing fastener connections, fastener spacing, wall aspect ratio, and material properties. A total of 142 full scale test data was used to verify the proposed design method and the supporting design equations. The proposed design approach shows consistent agreement with the test results and the AISI published nominal strength values. Simplified nominal strength model was developed to predict the nominal shear strength of cold-formed steel framed wood-based panel shear walls. The nominal shear …
Date:
May 2013
Creator:
Yanagi, Noritsugu
System:
The UNT Digital Library
Arvo Pärt and Three Types of His Tintinnabuli Technique
Arvo Pärt, an Estonian composer, was born in 1935. Most of the works at the beginning of his career were for piano in the neo-classical style. After that, he turned his interest to serial music and continued creating works with serial techniques throughout the 1960s. After his "self-imposed silence" period (during the years 1968-1976), Pärt emerged with a new musical style, which he called tintinnabuli. Although, this technique was influenced by music from the medieval period, the texture and function of its musical style cannot be described easily in terms of any single musical technique of the past. This study explores the evolution of Arvo Pärt's tintinnabuli technique in its first decade 1976-1985, which is divided into three different types. It provides musical examples from the scores of selected works, Für Alina, Cantus in Memory of Benjamin Britten, Cantate Domino canticum novum, Missa Sillabica, Stabat Mater and Es sang vor langen Jahren, and their analyses with supporting interpretative sketches. The goal of this thesis is to provide the reader a basis for understanding and recognizing the different types of Pärt's tintinnabuli technique.
Date:
May 2013
Creator:
Kongwattananon, Oranit
System:
The UNT Digital Library
Assessing the Role of Smaller Format Retailers on the Food Desert Landscape in Dallas, Texas
Many policy and business decisions regarding food deserts in the U.S. are based on the United States Department of Agriculture (USDA) definition of a food desert. This definition only includes large/national chain grocery retailers, based on the assumption that these major retailers are the only affordable sources of food contributing to balanced diets. As alternative distribution channels, including smaller stores, start to include groceries in their product offering, the need to consider the role of other businesses in the food retailing environment should be addressed. This thesis assesses the role of smaller format grocery retailers (small local grocers, convenience stores, gas stations, dollar stores, and drug stores) in shaping the food desert landscape in Dallas, Texas. The analysis evaluates the products offered in these stores, and then identifies the difference these stores make when included in the USDA analysis. This was done by collecting in-store data to determine the variety of products offered, the affordability of those products, and the overall healthfulness of the store. In addition, the gaps in supply and demand were identified in the USDA-defined food deserts in order to identify the impact any smaller format retailer may have. The findings suggest that, overall, smaller format retailers …
Date:
May 2013
Creator:
Regan, Amanda D.
System:
The UNT Digital Library
Attention Biases Associated with Vulnerability to Bipolar Disorder
Bipolar disorder is associated with significant social and occupational impairments, as well as increased risk for substance abuse and suicide. More research is needed to identify potential mechanisms associated with vulnerability to the disorder. Previous research has identified altered processing of emotional information in bipolar and bipolar-prone individuals, including attentional biases which appear to differ based on the current affective state of the individual. The current study applied a sensitive measure of attention (i.e., eye-tracking) to assess whether vulnerability to bipolar disorder, as indexed by hypomanic personality traits, would be correlated with biases in attention to emotional facial stimuli, independent of mood state. Hypomanic personality traits were hypothesized to be associated with greater attention to happy and angry faces, as indexed by faster initial orientation, more frequent gazes, and longer gaze duration for these stimuli. Participants completed self-report measures assessing current mood symptoms, positive and negative affect, and hypomanic personality traits. They then completed two tasks assessing attention for emotional faces. The first was an eye-tracking task, which measured latency to first fixation, total gaze duration and total number of gazes for each emotional face category. The second was a spatial cueing task which assessed both attentional engagement with emotional …
Date:
May 2013
Creator:
Bain, Kathleen Marie
System:
The UNT Digital Library
Automated Treetop Detection and Tree Crown Identification Using Discrete-return Lidar Data
Accurate estimates of tree and forest biomass are essential for a wide range of applications. Automated treetop detection and tree crown discrimination using LiDAR data can greatly facilitate forest biomass estimation. Previous work has focused on homogenous or single-species forests, while few studies have focused on mixed forests. In this study, a new method for treetop detection is proposed in which the treetop is the cluster center of selected points rather than the highest point. Based on treetop detection, tree crowns are discriminated through comparison of three-dimensional shape signatures. The methods are first tested using simulated LiDAR point clouds for trees, and then applied to real LiDAR data from the Soquel Demonstration State Forest, California, USA. Results from both simulated and real LiDAR data show that the proposed method has great potential for effective detection of treetops and discrimination of tree crowns.
Date:
May 2013
Creator:
Liu, Haijian
System:
The UNT Digital Library
The Beliefs and Expectations of Effective Secondary Choral Teachers in Culturally Diverse Schools
Through the years, educational theorists and researchers have been interested in a possible relationship between teachers' effectiveness and their beliefs and expectations. Three concepts underpinned this work: teacher effectiveness, cultural diversity, and teachers' beliefs and expectations. The premise of the study was that the beliefs and expectations of effective secondary choral teachers are related to the social-cultural contexts in which they teach. The study implemented critical discourse analysis as the theoretical framework and the in-depth phenomenological long interview for data collection. Three secondary choral teachers were selected to participate in the study based on the researcher's criteria. The study revealed how each teacher conceptualized student cultural diversity during the teaching experience. Teacher beliefs about effective teaching in culturally diverse settings were described as developing over time in phases along a continuum. The study also confirmed that teachers' beliefs about students can be changed through experiences and reflection. The study revealed effective teachers focused on three different types of expectations in the teaching and learning context and affirmed diverse cultural identities and backgrounds. Recommendations included the development of stronger mentorship programs to increase effective teaching strategies for the secondary choral classroom. The findings of this study support my previous work, which …
Date:
May 2013
Creator:
Spradley, Mackie V.
System:
The UNT Digital Library
Bioconcentration and Morphological Effects of Triclosan on Three Species of Wetland Plants
Triclosan (TCS) is an antimicrobial compound found in several types of common household products. After being washed down the drain, TCS will then end up in the local watershed. Although numerous studies have been conducted to evaluate the fate and effects of TCS in aquatic environments, there have been no studies evaluating the role arbuscular mycorrhizal fungi (AM) play in a plants response to TCS exposure. Three species of wetland plants native North Texas were inoculated with AM spores and exposed to 0, 0.4 g/L and 4.0 g/L TCS concentrations. Root morphology of E. prostrata and S. herbacea showed AM and exposure responses. S. herbacea produced the greatest amounts biomass and TCS bioaccumulation, in all but one treatment. It also displayed opposing results to E. prostrata in measures of root length, root surface area, relative root mass, relative shoot mass and shoot:root ratio. TCS root tissue concentrations increased with increased exposures for both E. prostrata and S. herbacea. Even though E. prostrata had the lowest levels in each measure of biomass production, it had the highest amount of root TCS bioaccumulation in the AM inoculated 4.0 g/L treatment. H. laevis was between the other two species in terms of biomass …
Date:
May 2013
Creator:
Smith, Caleb M.
System:
The UNT Digital Library
Blood and Earth: Indivisible Territory and Terrorist Group Longevity
The study of terrorism has been both broad in scope and varied in approach. Little work has been done, however, on the territorial aspects of terrorist groups. Most terrorist groups are revolutionary to one degree or another, seeking the control of a piece of territory; but for the supportive population of a terrorist group, how important is the issue of territory? Are the intangible qualities of territory more salient to a given population than other factors? Are territorially based terrorist groups more durable than their ideologically or religiously motivated cohorts? This paper aims to propose the validity of the territorial argument for the study of political terrorism.
Date:
May 2013
Creator:
Glass, Richard A.
System:
The UNT Digital Library
Brass Band History and Idiomatic Writing in Brass Music
The purpose of this research was to explore historical perspective of brass music. There is a brief history of brass bands in Britain. Furthermore, the paper examines the differences between two brass band pieces in the repertoire, A Western Fanfare by Eric Ewazen and Brass Symphony by Jan Koetsier. Both of these pieces were compared and contrasted against the author's newly composed work for brass, Two Companion Pieces for Brass Ensemble. The paper covers different techniques commonly used in brass writing and points these techniques out in all three pieces.
Date:
May 2013
Creator:
Kahler, Elyse T.
System:
The UNT Digital Library
Breaking Outside: Narratives of Art and Hawaii
This research examines the personal narratives of two contemporary non-native artists living and working on the island of Oahu, Hawaii. Issues related to narratives, power structures, artistic processes, insider/outsider dynamics, Hawaiian culture, island life, surfing, and the researcher's own experiences are woven together to formulate realizations surrounding alternative knowledge systems and the power of multiple or hidden narratives to the practice of art education.
Date:
May 2013
Creator:
Davidson, Allison B.
System:
The UNT Digital Library
The Character of Environmental Citizenship: Virtue Education for Raising Morally Responsible Individuals
Surely, moral education is not merely intended to result in theoretical knowledge, but instead attempts to change people's behavior. However, when examining and evaluating current trends in moral education, it appears that hitherto moral education has fallen short of its goal to make people better. In this paper, I try to determine what has caused this perceived failure of moral education and conclude that approaches that focus on teaching moral reasoning skills rather than on teaching actual moral content, i.e., values and virtues, are generally ineffective for moral improvement. However, a more traditional form of moral education, namely character education, appears to be a viable alternative to the moral reasoning methods. Since character education can be regarded as the practical application of virtue ethics, I first describe and evaluate virtue ethics and defend it against potential criticisms. I then examine what methods are effective for teaching virtues, and how such methods can potentially be incorporated into the curriculum. Since virtues cannot be taught through theoretical instruction, the acquisition of good habits constitutes the necessary foundation for the establishment of good moral character. Some methods that have been suggested for laying the foundation for virtue are the use of stories, role …
Date:
May 2013
Creator:
Lindemann, Monica A.
System:
The UNT Digital Library
Classless: on Being Middle Class in America
Classless: On Being Middle Class in America is a documentary film that explores what it means to be middle class in America. The film combines personal narrative, folksy reporting, and comedy as the film's director— Joe Brown, tries to reconcile his own status anxiety with everyday understandings of social class. Classless takes the form of a journey; the film travels through the American South, Northeast, and the Mountain West while trying to get at the heart of our middle class American Dream. Classless forwards three main arguments: (1) the American middle class is not as all-encompassing as seems; (2) Americans are more concerned about inequality than both politicians and the media suggest; and (3) many Americans are not actually middle class, economically speaking.
Date:
May 2013
Creator:
Brown, Joseph V.
System:
The UNT Digital Library
Cold-formed Steel Framed Shear Wall Sheathed with Corrugated Sheet Steel
Incombustibility is one important advantage of the sheet steel sheathed shear wall over wood panel sheathed shear wall. Compared to shear wall sheathed with plywood and OSB panel, shear wall sheathed with flat sheet steel behaved lower shear strength. Although shear wall sheathed with corrugated sheet steel exhibited high nominal strength and high stiffness, the shear wall usually behaved lower ductility resulting from brittle failure at the connection between the sheathing to frames. This research is aimed at developing modifications on the corrugated sheathing to improve the ductility of the shear wall as well as derive practical response modification factor by establishing correct relationship between ductility factor ? and response modification factor R. Totally 21 monotonic and cyclic full-scale shear wall tests were conducted during the winter break in 2012 by the author in NUCONSTEEL Materials Testing Laboratory in the University of North Texas. The research investigated nineteen 8 ft. × 4 ft. shear walls with 68 mil frames and 27 mil corrugation sheet steel in 11 configurations and two more shear walls sheathed with 6/17-in.OSB and 15/32-in. plywood respectively for comparison. The shear walls, which were in some special cutting arrangement patterns, performed better under lateral load conditions according …
Date:
May 2013
Creator:
Yu, Guowang
System:
The UNT Digital Library
Community Resilience in Thailand: a Case Study of Flood Response in Nakhonsawan City Municipality
Natural disasters such as flooding often affect vast areas and create infinite demands that need to be addressed in the same time. The wide scopes and severe impacts of such catastrophes often exceed, if not overwhelm, capacity of the national government to handle. In such a situation, communities such as cities and neighborhoods need to rely on their own capacity (resources, strategies, and expertise) to respond to disaster impacts at least until external assistance can be reached. Thus, studying how communities can be resilient to the impacts of natural disasters is important because this would enhance their ability to respond to the next disaster better. Within the context of great flooding in Thailand in 2011, this dissertation investigated the factors that generated or enhanced resilience of flood stricken-communities in Thailand. Nakhonswan City Municipality was selected as the research site. Qualitative research methods were employed in this study. Data were collected using in-depth interview and focus group. Thirty-six participants (28 for in-depth interview and 8 for focus group interview) from various organizations were recruited using snowball and purposive sampling strategies. Interview data from the field research were transcribed, translated from Thai language to English, and then analyzed using open coding and …
Date:
May 2013
Creator:
Khunwishit, Somporn
System:
The UNT Digital Library
A Comparative Study of the Effects of State Grant Reductions on Local Expenditures: Empirical Studies in Massachusetts and Colorado Municipalities
State grants are perceived to mitigate the fiscal disparities among local governments in providing services. However, cutbacks in state grants as a result of changes in state grant policy in different states affect local expenditures dedicated to maintaining service provisions to citizens. This dissertation constructs a theoretical model to explain the extent to which and the ways in which types of state grants, revenue diversity, and form of local government impact local spending and the provision of public programs when local governments experience cuts in state grants. The dissertation also argues that when facing state grant cuts, local governments with a council-manager form of government and with higher revenue diversity will experience reduced change in local expenditures and that decreases in state categorical grants will lead to more cuts in distributive program expenditures. Given the diversity of state and local arrangements, this dissertation conducts a comparative and panel data study to test the hypotheses in 351 and 271 municipalities in Massachusetts and Colorado, respectively, in 2000 through 2008. The empirical results indicate that the form of government and the degree of revenue diversification have a greater impact on the local spending behaviors in Colorado than in Massachusetts. Meanwhile, decreases in …
Date:
May 2013
Creator:
Chaicharoen, Siwaporn
System:
The UNT Digital Library
Connecting the Circuit: Analyzing Jurors' Cognitive Gaps and Damage Awards in Patent Infringement Trials
Patent litigation is notorious for the technicality of evidence and the rhetoric of experts. Citizens selected to serve on the jury have no specialized training and have rarely been exposed to the technology or the patent process. This study provides insight into the field of jury decision-making in complex patent cases by analyzing the cognitive gaps and the tactics used by jurors to minimize them. Additionally, the study examines the justifications for the damage awards jurors provide. This analysis focused on jurors engaged in mock trial patent deliberations. The story model and sensemaking theory serve as the theoretical framework of this research and provide a structure for support and a lens for analysis. The results indicate that jurors rely on three distinct and dichotomous topologies when navigating cognitive gaps. Searching for answers either individually or as a group, relying on lists or stories, and turning to facts or emotions, jurors navigate through their uncertainty. Through the line-by-line analysis of mock jury transcriptions, three continuums regarding damage justifications emerged. Jury members found themselves navigating uncertainty versus certainty, rationality versus irrationality, and facts versus emotions. The theoretical implications broaden the story model to include cognitive gaps in all phases and increase the …
Date:
May 2013
Creator:
Drescher, L. Hailey
System:
The UNT Digital Library
Consistency, Consolidation, and Cognition in Autobiographical Memories: a Flashbulb Memory Approach
Flashbulb memories are highly vivid and long-lasting memories for events that are emotionally significant and personally important. These memories are held in very high confidence in accuracy over an extended period. In particular, individuals believe that they can remember the personal details surrounding the event such as where they were and what they were doing at the time the event occurred. Evidence from research, however, indicates that this may not be the case. The study of flashbulb memories has typically been confined to negative events such as September 11, 2001. In the current study, we employ the methods of Talarico and Rubin (2003) to investigate flashbulb memory formation to a positive event. The event is the assassination of Osama bin Laden, which resonated as a highly positive event for many Americans evidenced by the thousands of people flooding the streets of Washington, D.C. and New York City to celebrate. We examined various memory properties over a one-year period, including vividness, rehearsal, belief in accuracy, and consistency. Results confirm the formation of flashbulb memories to the assassination event, but results did not support many of the proposed hypotheses. Some differences were found for different testing groups (i.e., immediate versus one week …
Date:
May 2013
Creator:
Kraha, Amanda
System:
The UNT Digital Library
Convergent Validity of Variables Residualized By a Single Covariate: the Role of Correlated Error in Populations and Samples
This study examined the bias and precision of four residualized variable validity estimates (C0, C1, C2, C3) across a number of study conditions. Validity estimates that considered measurement error, correlations among error scores, and correlations between error scores and true scores (C3) performed the best, yielding no estimates that were practically significantly different than their respective population parameters, across study conditions. Validity estimates that considered measurement error and correlations among error scores (C2) did a good job in yielding unbiased, valid, and precise results. Only in a select number of study conditions were C2 estimates unable to be computed or produced results that had sufficient variance to affect interpretation of results. Validity estimates based on observed scores (C0) fared well in producing valid, precise, and unbiased results. Validity estimates based on observed scores that were only corrected for measurement error (C1) performed the worst. Not only did they not reliably produce estimates even when the level of modeled correlated error was low, C1 produced values higher than the theoretical limit of 1.0 across a number of study conditions. Estimates based on C1 also produced the greatest number of conditions that were practically significantly different than their population parameters.
Date:
May 2013
Creator:
Nimon, Kim
System:
The UNT Digital Library
Corrosion Protection of Low Carbon Steel By Cation Substituted Magnetite
Surfaces of low carbon steel sheet were modified by exposure to highly caustic aqueous solutions containing either chromium or aluminum cations. Corrosion resistances of such surfaces were compared with that of steel surfaces exposed to plain caustic aqueous solution. In all cases a highly uniform, black coating having a spinel structure similar to magnetite (Fe3O4) was obtained. The coated steel surfaces were characterized using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared spectrophotometry (FTIR). Polarization resistances (Rp) of modified steel surfaces were measured and compared with that of bare steel surfaces. Results indicate that chromium (Fe2+ Fe3+x Cr3+1-x) or aluminum (Fe2+ Fe3+x Al3+1-x) substituted spinel phases formed on steel surfaces showed higher Rp values compared to only magnetite (Fe2+ 2Fe3+O4) phase formed in the absence of either chromium or aluminum cations. Average Rp values for steel surfaces with chromium containing spinel phase were much higher (21.8 k?) as compared to 1.7 k? for bare steel surfaces. Steel surfaces with aluminum containing spinel phase and steels with plain magnetite coated samples showed average Rp values of 3.3 k? and 2.5 k? respectively. XPS and EDS analysis confirmed presence of cations of chromium and …
Date:
May 2013
Creator:
Phadnis, Ameya
System:
The UNT Digital Library