The spallation of aluminum, chromium, and iron oxide scales is a chronic problem that critically impacts technological applications like aerospace, power plant operation, catalysis, petrochemical industry, and the fabrication of composite materials. The presence of interfacial impurities, mainly sulfur, has been reported to accelerate spallation, thereby promoting the high-temperature corrosion of metals and alloys. The precise mechanism for sulfur-induced destruction of oxides, however, is ambiguous. The objective of the present research is to elucidate the microscopic mechanism for the high-temperature corrosion of aluminum alloys in the presence of sulfur. Auger electron spectroscopy (AES), low energy electron diffraction (LEED), and scanning tunneling microscopy (STM) studies were conducted under ultrahigh vacuum (UHV) conditions on oxidized sulfur-free and sulfur-modified Al/Fe and Ni3Al(111). Evaporative deposition of aluminum onto a sulfur-covered iron surface results in the insertion of aluminum between the sulfur adlayer and the substrate, producing an Fe-Al-S interface. Aluminum oxidation at 300 K is retarded in the presence of sulfur. Oxide destabilization, and the formation of metallic aluminum are observed at temperatures > 600 K when sulfur is located at the Al2O3-Fe interface, while the sulfur-free interface is stable up to 900 K. In contrast, the thermal stability (up to at least 1100 …

The purpose of this study is to analyze sets of variations on Paganini's theme by three twentieth-century composers: Ferruccio Busoni, Ignaz Friedman, and Robert Muczynski, in order to examine, identify, and trace different variation techniques and their applications. Chapter 1 presents the purpose and scope of this study. Chapter 2 provides background information on the musical form "theme and variations" and the theme of Paganini's Twenty-fourth Caprice, Op. 1. Chapter 2 also deals with the question of which elements have made this theme so popular. Chapters 3,4, and 5 examine each of the three sets of variations in detail using the following format: theme, structure of each variation, harmony and key, rhythm and meter, tempo and dynamics, motivic development, grouping of variations, and technical problems. Chapter 6 summarizes the findings from this study and attempts to compare those elements among the three variations. Special attention is given to the application of the motivic cells, which are drawn from the original Paganini theme, in the development of succeeding variations. This study shows how these motivic cells contribute to the construction of new motives and melodies in each variation. Additionally, this study attempts to examine each composer's efforts in expanding variation procedure …

The first purpose of this study was to develop and validate the Inventory of Opinions About Persons with Disabilities (IOPD). The IOPD was developed to collect preservice early childhood educators’self-report data related to inclusion. A total of 332 participants enrolled in graduate programs in a college of education served as the validation sample. After validation and revision of the IOPD, the researcher used the instrument to investigate preservice early childhood educators’ beliefs, attitudes, and knowledge about students with disabilities and their inclusion in general education classrooms. Data were collected from 172 participants from 10 universities in Texas during their student teaching/final intern semesters. This research demonstrated that an instrument, the IOPD, could be developed to effectively measure preservice early childhood educators’ beliefs, attitudes, and knowledge about the inclusion of children with disabilities in their classrooms. The participants reported positive self-perceptions (mean = 2.0388) about their beliefs and attitudes toward inclusion. However, the participants reported less positive attitudes about training (mean = -.09884). Discriminant function analyses indicated a negligible statistical effect for type of program (professional development school or traditional) and a statistically significant effect for preferred classroom setting (non-inclusive, special education, inclusive). Further research with the same participants or similar …

Because computer use become more and more important in the educational environment, the attitudes of students toward computer may play an important role in their learning success. This study investigated the attitudes toward computers and gender differences of sixth-grade Kuwaiti students and examined the relationships between students’ attitudes toward computers and school, motivation/persistence, study habits, empathy, creative tendencies, and achievement in the Informatics field. The Computer Attitude Questionnaire (CAQ), translated from the English into Arabic Language for this study, was originally developed by Knezek and Miyashita for the Texas Center for Educational Technology (University of North Texas). The CAQ was administered to a random cluster sample of 10 public middle schools: (5 boys’ and 5 girls’ schools), with a total of 562 students, (265 boys and 297 girls), in the State of Kuwait during the academic year 1999-2000. The pilot test was conducted to calculate the reliability with Cronbach’s alpha = .87 for the CAQ Arabic version. This study found positive attitudes toward computer use (mean = 3.31 on 4-point Likert-scale); however, girls had significantly more positive attitudes toward computers (mean = 3.36) than did boys (mean = 3.26). It also found statistically significant correlations between attitudes toward computers and …

Quarterly publication of the Alpha Chi Sigma chemistry fraternity containing articles related to chemistry research and the activities of the organization, including local chapters and groups.

Change is best carried out by individual teachers, and, thus, identifying and resolving teachers’ concerns about an innovation is imperative in guiding the change process to a successful point of implementation. The purpose of this study was to identify concerns that teachers experienced when implementing the Information Technology curriculum in all intermediate schools in Kuwait and to examine the relationships among teachers’ reported stages of concern and other factors, such as gender and experience. The stages of concern, one dimension of the Concerns-Based Adoption Model (CBAM), was applied to reveal teachers’ concerns. The Stages of Concern Questionnaire (SoCQ) and a demographic survey were completed by 248 respondents. The SoCQ measures seven stages of concern that reflect three dimensions: self (awareness, informational, and personal); task (management); and impact (consequence, collaboration, and refocusing Group profile analysis revealed that teachers had four high concerns related to collaboration, personal, refocusing, and informational stages. Teachers also reported low concerns at the management and awareness stages. Both females and males reported collaboration as their greater concern. Teachers with more years of experience reported higher impact concerns. The analysis of individuals’ peak concerns revealed that the majority of the respondents were adopters of the innovation. The analysis …

Human operant studies frequently use points exchangeable for money as reinforcers. Some studies employ more immediately consumable reinforcers to emulate properties of food reinforcers. This study examined demand for points/money and for sound-clips to compare their economic characteristics. Across four participants, demand was often higher and less elastic for points/money than for sounds. During subsequent exposures at each response requirement, demand for sounds often decreased to a greater degree than demand for points/money. Thus, sound-clips seem less durable than points/money across prices and across repeated exposure to the same price. Response rates for points/money were often higher than for sounds, suggesting that reinforcers that generate higher response rates may be less elastic than reinforcers that generate lower response rates.

The purpose of this study was to investigate the effects of web-based instruction (WBI) on cognitive and psychomotor learning. The subjects of the study received two types of instructional methods, WBI (experimental group) and traditional classroom instruction (control group). Each group received 30 minutes of instruction on "Soldering a Circuit Board." The researcher chose this content subject because it involved both cognitive and psychomotor objectives, which suited the purpose of this study. It was hypothesized that there would be no significant difference between the two methods of instruction, and also that there would be no significant interaction effects between methods of instruction and gender. Forty-six subjects from a population of students enrolled in summer classes offered by the Applied Technology, Training and Development (ATTD) program at the University of North Texas voluntarily participated in this study. Random assignment of subjects was applied in this study. A subject matter expert delivered the content for both the experimental and control groups. To measure cognitive variable, a 10 item, multiple-choice test was administered immediately after instruction. To measure the psychomotor variable, a 15-item checklist was utilized by trained judges to evaluate learners’ performances while soldering. The 2 x 2 factorial model with interaction …

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.

Periodic supplement for "the regular journals of the American Chemical Society," containing annotated bibliographies of chemical documentation literature as well as information about meetings, conferences, awards, scholarships, and other news from the American Chemical Society (ACS) Division of Chemical Literature.

Periodic supplement for "the regular journals of the American Chemical Society," containing annotated bibliographies of chemical documentation literature as well as information about meetings, conferences, awards, scholarships, and other news from the American Chemical Society (ACS) Division of Chemical Literature.

This experiment examined the effects of extinction on rate of responding and several topographical and temporal measures in adult humans. Three college students were trained to type the sequence 1•5•3 on a numeric keypad on a computer. The subjects were exposed to different fixed-ratio schedules of reinforcement (FR1, FR 5, and FR10 respectively) and extinction. Subjects displayed typical schedule performances during the maintenance phase of the experiment. During extinction the performances were disrupted, they showed a "break and run" pattern and a general decrease in responding. Also, new topographical and temporal patterns emerged. These data are consistent with those reported for non-human species and special human populations.

Heart of the Fathers is a programmatic, seven movement work for wind symphony depicting my ancestors and their role as part of the history of The Church of Jesus Christ of Latter-day Saints. The movements represent their spiritual experiences, labors, times of joy, persecution, migration, and finally their arrival and success in their new homeland. The piece is organized in seven movements. Each movement represents a different portion of history leading to the western migration of my ancestors. The programmatic music contains a variety of symbols depicting the experiences of the pioneers. In the paper, each chapter addresses an individual movement. For each movement, the following information is provided: the historical events that inspired the piece, the musical symbols that characterize the program, and an analysis of the function of the music.

Journal containing essays, commentaries, and exhibition information regarding Texas artwork and other contemporary art issues.

The purpose of this study was to use the Global Water Stormwater Sampler SS201 to characterize the urban runoff in Pecan Creek. Location of the samplers was influenced by land use and ease of installation. Determination of the constituents for analysis was modeled after those used in the NPDES permit for seven cities within the Dallas/Ft.Worth metroplex. Some metals, notably cadmium and arsenic, exceeded the U.S. EPA's MCL's. Statistical analysis revealed first flush samples to be significantly more concentrated than composite samples. Minimum discharge loadings were found to be significantly lower than maximum discharge loadings. Additionally there were significant differences of specific constituents between station locations and storm events.

The purpose of this qualitative multi-case study was to explore the nature of the impact that a tutoring program, which featured preservice teachers as tutors, had on participating fifth grade at-risk students’ literacy behaviors in the classroom.The researcher served in the role of passive participant observer during the scheduled language arts period three days per week in the participating students’ classroom for a period of twenty-three weeks. Field notes were made in the classroom and coded, and audio tapes were recorded and transcribed of the tutoring sessions. Formal and informal interviews with the teacher, tutors, and participating students were conducted, transcribed, and coded. Lesson plans and reflections developed and written by the tutors were gathered and coded. Observations indicated that there were four types of reading required on a daily basis in the classroom. Assigned readings made by the teacher included narrative and expository texts. Pleasure readings were materials chosen by the students, but at certain times were teacher initiated and at other times, student initiated. The four types of reading found in the classroom were mirrored by the tutoring sessions. Students observed in the classroom could be divided into two types and four categories. Those with positive attitudes were …