Current Search: remediation (x)
View All Items
- Title
- REACTION RATES FOR THE DEHALOGENATION OF TRICHLOROETHYLENE USING VARIOUS TYPES OF ZERO-VALENT IRON.
- Creator
-
Stewart, Neil, Clausen, Christian, University of Central Florida
- Abstract / Description
-
Remediation of trichloroethylene (TCE) and other chlorinated solvents is of great concern due to their toxicity and their persistence in the environment. Iron has been used extensively in the past decade as a subsurface reactive agent for the remediation of dense, nonaqueous-phase liquids (DNAPLs). Permeable reactive barrier walls (PRBW) have been installed at many sites around the country to treat contaminated plumes resulting from the presence of DNAPL pools. The use of zero-valent metals,...
Show moreRemediation of trichloroethylene (TCE) and other chlorinated solvents is of great concern due to their toxicity and their persistence in the environment. Iron has been used extensively in the past decade as a subsurface reactive agent for the remediation of dense, nonaqueous-phase liquids (DNAPLs). Permeable reactive barrier walls (PRBW) have been installed at many sites around the country to treat contaminated plumes resulting from the presence of DNAPL pools. The use of zero-valent metals, such as iron, to effectively reductively dechlorinate DNAPLs has been employed as the reactive material in these PRBWs (Gillham et al., 1993). However, limited work has been conducted to compare the kinetics of TCE degradation related to various manufacturing sources of iron and the pretreatment the iron receives prior to subsurface installation. Determination of iron reactivity through kinetic studies makes it possible to compare different types of iron and the effects that pretreatment has on reactivity. This research utilized rate studies, scanning electron microscopy, and BET surface area analysis for iron particles that were obtained from several sources. Peerless Metal Powders and Abrasive, Inc., Connelly-GPM, Inc., and Alfa Aesar Inc., produced the iron particles using various manufacturing techniques, and nanoscale iron was synthesized in our laboratory. By utilizing zero-headspace batch vial experiments and gas chromatography, changes in TCE concentration were determined. The data obtained produced linear first order rate plots from which dehalogenation rate constants were obtained. The rate constants were normalized by iron mass, solution volume, and surface area. The pretreatment techniques employed in this study, including ultrasonication and acid washing, demonstrated a beneficial effect by removing oxide precipitates from the iron surface, thus increasing the reactivity of the iron. Mass loading studies revealed how physical factors, associated with the experimental setup, could influence reaction rates. Surface area studies confirmed that the smaller iron particles, such as the nanoscale iron, have a greater surface area per unit mass. The large mass and volume normalized rate constant, kMV, obtained for the nanoscale iron was a result of this high surface area. However, the calculated surface area normalized rate constant, kSA, for the nanoscale iron was significantly lower than those for the granular iron samples tested. It was concluded that differences in surface area normalized rate constants, between different iron particle types, could be attributed to inherent characteristics of the iron, such as composition and crystal structure.
Show less - Date Issued
- 2005
- Identifier
- CFE0000797, ucf:46583
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000797
- Title
- IN SITU REMEDIATION OF HEAVY METAL CONTAMINATED SEDIMENTS USING EMULSIFIED ZERO-VALENT METAL PARTICLES.
- Creator
-
Milum, Kristen, Geiger, Cherie, University of Central Florida
- Abstract / Description
-
Sediments can act as both a sink for pollutants and a source for aquatic contaminants. Natural and human disturbances of the sediments can release the contaminants to the overlying water where bottom dwelling, or benthic, organisms may be exposed through direct contact, ingestion of sediment particles, or uptake of dissolved contaminants present in the water. Dredging, the most common remediation technology for heavy metals, exacerbates this process. The in situ use of emulsified metal has...
Show moreSediments can act as both a sink for pollutants and a source for aquatic contaminants. Natural and human disturbances of the sediments can release the contaminants to the overlying water where bottom dwelling, or benthic, organisms may be exposed through direct contact, ingestion of sediment particles, or uptake of dissolved contaminants present in the water. Dredging, the most common remediation technology for heavy metals, exacerbates this process. The in situ use of emulsified metal has been studied for its ability to pull heavy metals from aqueous solution and from saturated soils. It has proven successful in the laboratory with removal of lead, cadmium, copper, nickel, and uranium from aqueous solution and removal of lead and cadmium from saturated spiked soils. The use of zero-valent metal particles, particularly those of zero-valent iron (Fe0), as an in situ remediation technique, is currently undergoing evaluation. The basic mechanism for removal appears to be reduction of contaminant metals followed by the subsequent precipitation of their insoluble forms. This is accompanied by the oxidation of the zero-valent metal. In the case of iron, Fe0 undergoes oxidation to Fe2+ and then to the Fe3+ state. Particulate Fe0 has been shown to precipitate Cr6+ to Cr3+ and Pb2+ undergoes reduction to Pb0. Initially, zero-valent iron filings were used to reduce the metal contaminants, but it has been shown that smaller size iron particles, such as nano-scale iron, have higher initial reduction rates as well as a higher concentration of contaminant removal per mole of iron. Emulsion liquid membrane (ELM) technology has been employed as a remediation technique for the removal of metals from wastewater where extraction and stripping processes are performed in a single operation. The ELMs are made by forming an emulsion between two immiscible liquids, such as oil and water, and are often stabilized by a surfactant. We have attempted to demonstrate the application of the combination of these two technologies through the use of emulsified zero-valent metal (EZVM) to treat sediments with heavy metal contamination. Emulsions were prepared using vegetable oil, water, Span 85, and either nanoscale Fe, 1-3 Ým Fe, 4 Ým Mg, or a 20 wt % Fe-Mg mixture. The results presented in this study demonstrate that EZVM is a viable technique for in situ remediation of heavy metals in sediments. Laboratory scale studies have shown high levels of removal of lead and cadmium from solution using emulsified zero-valent iron. Additionally, the use of emulsified magnesium has shown the ability for high levels of removal of copper, cadmium, nickel, lead, and uranium from solution. A variety of solution matrices were also explored for a lead solution including seawater, the presence of complexing agents and humic acids. Small-scale laboratory studies have shown 65% removal of lead and 45% removal of cadmium from saturated, spiked soils. A bench scale test to demonstrate the applicability of this technique in the environment revealed similar results for the removal of lead.
Show less - Date Issued
- 2005
- Identifier
- CFE0000665, ucf:46510
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000665
- Title
- Math Remediation for High School Freshmen.
- Creator
-
Borhon, Kambiz, Boote, David, Hynes, Mike, Gunter, Glenda, Miller, Margaret, University of Central Florida
- Abstract / Description
-
This study is an attempt to address the problem associated with a high percentage of freshman students, at a private Christian high school in Florida, who either fail Algebra 1 or pass with a low percentage rate. As a result, these students either retake Algebra 1 or continue on(-)being inadequately prepared to successfully pass Geometry and Algebra 2. This study concentrates on the student background knowledge of mathematics, which is among the causes associated with this problem, and...
Show moreThis study is an attempt to address the problem associated with a high percentage of freshman students, at a private Christian high school in Florida, who either fail Algebra 1 or pass with a low percentage rate. As a result, these students either retake Algebra 1 or continue on(-)being inadequately prepared to successfully pass Geometry and Algebra 2. This study concentrates on the student background knowledge of mathematics, which is among the causes associated with this problem, and proposes remediation. As such, a mathematics remediation course is designed and implemented for a select number of incoming freshmen. This study includes a correlational examination to determine a possible correlation between students' background knowledge of the middle school mathematics and predicts a possible failure or successful completion of Algebra I in high school. In addition, it purposes a two-stage evolution plan in order to determine the effectiveness of the design of the remedial course as well as its effectiveness. Undertaking the design evaluation, this study uses a mixed-modes design consisting of a qualitative (interview and observation) of a number of participants and a quantitative examination (survey) of a larger sample. The correlational study indicates that there is a positive and moderately strong correlation between students' background knowledge in (middles school) mathematics and their grades in Algebra 1. The evaluation concludes that students find the design of the MIP program helpful and aesthetically appealing; however, its usability did not meet the evaluation criteria. Furthermore, the MIP Program Manager and teacher are fully satisfied with its design, content, and components.
Show less - Date Issued
- 2015
- Identifier
- CFE0005581, ucf:50251
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005581
- Title
- Remediation of chlorinated alkanes by zero valent iron with vitamin B12 and Utilization of a modified Gradual Release of Responsibility model in a large enrollment chemistry course.
- Creator
-
Lapeyrouse, Nicole, Yestrebsky, Cherie, Beazley, Melanie, Chen, Gang, Rex, Matthew, Randall, Andrew, University of Central Florida
- Abstract / Description
-
The following dissertation looks at addressing environmental contaminants in the environment and the integration of an active learning style in an introductory chemistry course. It begins with addressing the concern for chlorinated propanes and ethane in the environment and the importance of looking into environmental remediation applications. This research looks at incorporating vitamin B12 as an environmentally friendly catalyst in the presence of zero valent iron for the reduction of...
Show moreThe following dissertation looks at addressing environmental contaminants in the environment and the integration of an active learning style in an introductory chemistry course. It begins with addressing the concern for chlorinated propanes and ethane in the environment and the importance of looking into environmental remediation applications. This research looks at incorporating vitamin B12 as an environmentally friendly catalyst in the presence of zero valent iron for the reduction of chlorinated propanes and ethane. Chapter 2 presents the analytical methods and conditions in which samples were run. The results from these experiments are discussed in length in Chapter 3. Our results confirmed the hypothesis that vitamin B12 could act as an electron mediator to facilitate the reduction of the chlorinated propanes and ethane. Degradation was examined by observing the formation of byproduct peaks and the release of free chloride into solution. In Chapter 4, vitamin B12 is integrated into an already established industrial application technique, emulsified zero valent iron, and we observed the degradation of 1,2,3-trichloropropane with the formation of byproducts as the reaction progressed. In Chapter 5, this section of the dissertation focused on chemical education and observing an active learning technique in a fundamental chemistry course. The following study was designed to increase students' positive attitude, engagement, and responsibility in a large enrollment chemistry course by utilizing a modified Gradual Release of Responsibility (GRR) model. GRR progressively transfers responsibility from the instructor to the student, allowing students to be more independent and helping them to address atypical problems. Students were assessed using iClickers to monitor their understanding and engagement, as well as surveys to determine their attitudes regarding this specific style of teaching. The results from this study demonstrated that implementing the GRR teaching style had a positive effect on student academic performance and shows the importance of using an active teaching model in a large enrollment course.
Show less - Date Issued
- 2018
- Identifier
- CFE0007759, ucf:52373
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007759
- Title
- A PHENOMENOLOGICAL INVESTIGATION OF COUNSELING STUDENTS' AND PRACTICUM SUPERVISORS' EXPERIENCES WITH THE COUNSELOR COMPETENCIES SCALE.
- Creator
-
Ascher, David, Lambie, Glenn, University of Central Florida
- Abstract / Description
-
Counselor educators are charged with facilitating the development of counseling students towards becoming ethical and competent counselors (American Counseling Association , 2005; Council for Accreditation for Counseling and Related Educational Programs , 2009). In addition, counselor educators serve as gatekeepers for the profession and deny entry to counseling students who demonstrate deficiency of necessary competencies (ACA, 2005; Association for Counselor Education and Supervision , 1993...
Show moreCounselor educators are charged with facilitating the development of counseling students towards becoming ethical and competent counselors (American Counseling Association , 2005; Council for Accreditation for Counseling and Related Educational Programs , 2009). In addition, counselor educators serve as gatekeepers for the profession and deny entry to counseling students who demonstrate deficiency of necessary competencies (ACA, 2005; Association for Counselor Education and Supervision , 1993; CACREP, 2009). Numerous assessment tools utilized for the evaluation of counseling competencies have been developed, yet none has gained universal acceptance in the field of counselor education. The Counseling Competencies ScaleĀ© (CCS, UCF Counselor Education Faculty, 2009) is a 32 item counseling-student assessment tool developed to measure counselors-in-training counselor competencies (counseling skills, professional dispositions, and behaviors). The psychometric properties of the CCS have been investigated (Swank, 2010); however, questions related to perceptions, purposes, and uses of the CCS remained. Therefore, the purpose of this descriptive, exploratory phenomenology was to understand counseling students' and practicum supervisors' lived experiences with the CCS. The sample included counseling practicum students (N = 23 [individual student interviews only, n = 11; student focus group interviews only, n = 4, individual student interviews and student focus group participants, n = 8]) and practicum supervisors (N = 6) from a CACREP accredited counselor education program in the Southeastern United States. The data was collected through individual interviews and focus groups with practicum students and individual interviews with practicum supervisors. All data was recorded, transcribed, coded, and analyzed for themes (Creswell, 2007; Moustakas, 1994). The data analyses utilized a research key comprised of 34 meaning units (Devenish, 2002; Moustakas, 1994) and identified five themes within the data: (a) Cognitive understanding, (b) Emotional Understanding, (c) Feedback, (d) Trustworthiness, and (e) Gatekeeping. A visual metaphor was developed to illustrate the interaction of the five themes. Trustworthiness measures employed throughout the research included the use of (a) descriptions of researcher positionality, (b) a self-reflective field journal, (c) triangulation (student and supervisor individual interviews, student focus group interviews, and examination of the CCS document), (d) member checking, (e) peer debriefers, (f) an external auditor, (g) an extensive description of previous literature, and (h) an openness to disconfirming evidence (Creswell, 2007; Marshall and Rossman, 2006; Moustakas, 1994). The results supported that counseling students and their clinical supervisors identified the CCS as an appropriate and comprehensive supervisory tool; however, they acknowledged CCS-related limitations including inconsistent application, problematic scoring system, pass/fail structure, and delivery by instructors and practicum supervisors who demonstrated minimal investment of time and effort. Implications for counselor educators include the importance of program and faculty members' engagement and consistency regarding the use of (a) evaluation and feedback tools, (b) remediation and gatekeeping processes, and (c) counseling student performance expectations. Replication of this study at diverse institutions is suggested. In addition, quantitative and qualitative investigations examining counseling student competencies and development (e.g., CCS) would contribute to the counselor education, counseling-student development, and counseling supervision literature. A discussion of the investigation's limitations is included.
Show less - Date Issued
- 2011
- Identifier
- CFE0003739, ucf:48764
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003739
- Title
- PEDAGOGICAL RE-MEDIATION IN HYBRID COURSES: A CASE STUDY OF FIVE FIRST-YEAR COMPOSITION INSTRUCTORS.
- Creator
-
Middlebrook, Rebecca, Wallace, David, University of Central Florida
- Abstract / Description
-
As the move to increase availability of composition courses in the online environment continues, it is important to understand the ways in which composition instructors have taken on the challenges associated with moving their teaching online and how they modify, or re-mediate, their pedagogy for the this new teaching and learning environment. This study takes on the task of examining re-mediation as it occurs in the pedagogical practices used by instructors to facilitate peer review...
Show moreAs the move to increase availability of composition courses in the online environment continues, it is important to understand the ways in which composition instructors have taken on the challenges associated with moving their teaching online and how they modify, or re-mediate, their pedagogy for the this new teaching and learning environment. This study takes on the task of examining re-mediation as it occurs in the pedagogical practices used by instructors to facilitate peer review activities in hybrid, first-year composition courses. At the same time, it is important to understand the varying factors that may influence the degree to which instructors re-mediate their pedagogy for this hybrid environment. This study also uncovers four factors that appeared to influence the degree to which the instructors re-mediated their pedagogical practices over the course of the semester in which this study was conducted. Results from this study will contribute to the field by serving as a guide to instructors and administrators who will teach and design hybrid composition courses or curricula in the future.
Show less - Date Issued
- 2009
- Identifier
- CFE0002881, ucf:48040
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002881
- Title
- POLITICAL SPACES AND REMEDIATED PLACES: REARTICULATING THE ROLE OF TECHNOLOGY IN THE WRITING CENTER.
- Creator
-
Carpenter, Russell, Bowdon, Melody, University of Central Florida
- Abstract / Description
-
Writing center directors (WCDs) often situate their programs in physical and virtual spaces without fully studying the pedagogical and political implications of their decisions. Without intense study, writing centers risk building programs within spaces that undermine their missions and philosophies. In The Production of Space, Henri Lefebvre argues that "From the analytic standpoint, the spatial practice of a society is revealed through the deciphering of its space" (38). The study of space...
Show moreWriting center directors (WCDs) often situate their programs in physical and virtual spaces without fully studying the pedagogical and political implications of their decisions. Without intense study, writing centers risk building programs within spaces that undermine their missions and philosophies. In The Production of Space, Henri Lefebvre argues that "From the analytic standpoint, the spatial practice of a society is revealed through the deciphering of its space" (38). The study of space also reveals important political and financial priorities within the institution. Furthermore, the positioning of buildings and the spatial layout of a campus display the institution's priorities and attitudes toward writing center work. Theorizing the Online Writing Lab (OWL) through the lens of cultural and political geographies, it becomes apparent that the physical spaces of many writing centers are not as sustainable as WCDs might like, and in many ways, they are marginalized within the larger institution. This dissertation prompts a rearticulation of place and space in the writing center. In this dissertation, I argue that in an attempt to rethink current practices, the virtual space of the writing center should perpetuate, extend, and improve the social practices employed in our physical spaces. I draw from mapping exercises to inform my critique in an attempt to advance our understanding of writing center physical and virtual spaces. The changing geographical and cultural landscape of the institution demands that writing centers pay close attention to spatial implications as they employ technology to create dynamic virtual resources and more sustainable spaces. I rearticulate writing center spaces through cognitive and digital mapping, urban planning, and architectural theories. I make several contributions through this work: theoretical, to rearticulate the physical and virtual space of writing center work; political, to understand the constructions of the writing center's pedagogical spaces; and pedagogical, to understand best practices for creating virtual spaces that enhance learning, unlike those we have seen before or have had available in the writing center.
Show less - Date Issued
- 2009
- Identifier
- CFE0002776, ucf:48092
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002776
- Title
- THE INFLUENCE OF HIGH SCHOOL DRAMATIC ARTS CLASSES ON REMEDIAL READERS ON THE FLORIDA COMPREHENSIVE ASSESSMENT TEST.
- Creator
-
Backel, Michelle, Murray, Barbara, University of Central Florida
- Abstract / Description
-
This is the age of accountability in public schools. The public wants to know that the schools are producing high achieving students who are ready for the future. With this push for accountability the rise in standardized testing should not be surprising. However, it is difficult to test an abstract course such as the arts. With the increase of standardized testing and the recent tough economic times, it is no wonder that performing arts classes in our public schools are often the first to be...
Show moreThis is the age of accountability in public schools. The public wants to know that the schools are producing high achieving students who are ready for the future. With this push for accountability the rise in standardized testing should not be surprising. However, it is difficult to test an abstract course such as the arts. With the increase of standardized testing and the recent tough economic times, it is no wonder that performing arts classes in our public schools are often the first to be pared down or dissolved (Mendels, 2008). It is the presiding feeling that these courses, while nice and fun for the students, do not offer any tangible, real, or marketable skills. ÃÂ"àimparting knowledge about the arts typically has not been a priority goal in our nationÃÂ's schoolsÃÂ" (Ward, 1983, ö 2). This study explored the benefits that students can achieve through their participation in the dramatic arts courses including, but not limited to, enhancement of reading and verbal scores. This study was designed to illustrate that the arts are a natural and necessary part of the high school educational experience and can play an instrumental part of learning even in a distressed economy, and/or in a regulated testing arena. Students who were freshmen or sophomores in 2008-2009 and scored a Level 1 or 2 (below average) score on the reading portion of the state test, the FCAT, and were from Orange and Seminole Counties in Florida became the sample set. These students were disaggregated into categories of students who took a dramatic arts course or not, by gender, by race, and by socioeconomic status to determine if participation in a dramatic arts course in high school would help raise a remedial reading score on the required state test. Although the data did not show a statistical significance, it did show a positive trend in a few of the tested areas. Suggestions for why the data appear to show only a trend and not significance are discussed further in Chapter 5.
Show less - Date Issued
- 2010
- Identifier
- CFE0003219, ucf:48582
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003219
- Title
- The Effectiveness of Placement Exams and a Free Remedial Summer Program at a Midsized Selective Private University.
- Creator
-
Mullins, Kadie, Murray, Kenneth, Baldwin, Lee, Doherty, Walter, Lindsley, Boyd, University of Central Florida
- Abstract / Description
-
In order to explore the effectiveness of MSSPU's remedial placement practices and the impacts of participation in the Free Remedial Summer Program on student outcomes, this ex post facto study examined performance in remedial courses, persistence to graduation, and time to graduation as it relates to mathematics and English composition placement level, high school grade point averages, entrance exam scores, and participation in the Free Remedial Summer Program. Five unique statistical tests...
Show moreIn order to explore the effectiveness of MSSPU's remedial placement practices and the impacts of participation in the Free Remedial Summer Program on student outcomes, this ex post facto study examined performance in remedial courses, persistence to graduation, and time to graduation as it relates to mathematics and English composition placement level, high school grade point averages, entrance exam scores, and participation in the Free Remedial Summer Program. Five unique statistical tests were utilized to address fifteen hypothesis related to seven research questions. Several major findings were a result of this study. First, students who complete the mathematics placement exam and enroll outside of their recommended level, either above or below their placement level, perform better in both their first and second mathematics courses, on average, than those who enroll at the recommended level. The same was found for English composition. Second, students who place at a non-remedial level are more likely to persist to graduation, statistically. Third, neither high school grade point average nor entrance exam scores alone are strong indicators of time or persistence to graduation. However, fourth, the factors of high school grade point average, entrance exam score, and placement exam performance may be a better indicator of persistence to graduation when analyzed in a combined fashion. Finally, students who enroll in the Free Remedial Summer Program are less likely to persist to graduation than those who enroll in remedial coursework as part of their first term. These students also are more likely to fail their first and subsequent mathematics courses. This study concludes with a brief analysis of implications for practice, recommendations for further research, and a review of best practices.
Show less - Date Issued
- 2016
- Identifier
- CFE0006150, ucf:51138
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006150
- Title
- Evaluation of the Effectiveness of the Third Grade Summer Reading Camp Intervention Program in a Larger Urban School District.
- Creator
-
Alchin, Danielle, Murray, Barbara, Taylor, Rosemarye, Murray, Kenneth, Baldwin, Gordon, University of Central Florida
- Abstract / Description
-
This study sought to evaluate the effectiveness of the third grade Summer Reading Camp (SRC) in a large urban school district. The SRC curriculum was assessed to determine if it aligned with effective remediation and filled the third grade students' knowledge voids in reading. The study further analyzed how the school district officials selected the curriculum content utilized in the SRC. This study was conducted using qualitative and quantitative methods. Data were collected through...
Show moreThis study sought to evaluate the effectiveness of the third grade Summer Reading Camp (SRC) in a large urban school district. The SRC curriculum was assessed to determine if it aligned with effective remediation and filled the third grade students' knowledge voids in reading. The study further analyzed how the school district officials selected the curriculum content utilized in the SRC. This study was conducted using qualitative and quantitative methods. Data were collected through questionnaires and interviews of school district personnel on the SRC committee regarding the implementation of the 2012 lesson plan, and from students' Winter Benchmark Assessment scores. The school district implemented the SRC to fulfill a state requirement that all students who received a Level 1 on the reading Florida Comprehensive Assessment Test (FCAT) Reading must receive remediation. The SRC committee designed the curriculum using the state reading benchmarks and decided the activities required during SRC would be whole group, small group, writing, and independent reading. The program was to be evaluated each year using teacher and administrator survey data and the analysis of test scores to determine changes to be implemented. Of the 10 benchmarks assessed on the school district reading benchmark test, only three were aligned with the students' knowledge voids. There were a total of eight FCAT tested reading benchmarks that were not taught during SRC. The researcher suggests the school district re-align the curriculum with the needs of the students as identified by the Winter Reading Benchmark. It is further recommended that each student's specific remediation needs be evaluated to ensure the curriculum is meeting the needs of all the students in attendance at SCR.
Show less - Date Issued
- 2013
- Identifier
- CFE0004803, ucf:49750
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004803
- Title
- LATINATE WORD PARTS AND VOCABULARY:CONTRASTS AMONG THREE GROUPS COMPRISINGTHE COMMUNITY COLLEGE PREPARATORY READING CLASS.
- Creator
-
Bellomo, Tom, Taylor, Rosemarye, University of Central Florida
- Abstract / Description
-
Students enrolled in a college preparatory reading class at one particular community college were categorized based on language origin. Native English speaking students comprised one group and foreign students formed two additional groups--students whose language origin was Latin-based (i.e. Romance languages) and students whose language origin was not Latin-based (i.e. Japanese). A pretest assessment measure was used to quantify the extent that pre-existing knowledge of Latinate word parts...
Show moreStudents enrolled in a college preparatory reading class at one particular community college were categorized based on language origin. Native English speaking students comprised one group and foreign students formed two additional groups--students whose language origin was Latin-based (i.e. Romance languages) and students whose language origin was not Latin-based (i.e. Japanese). A pretest assessment measure was used to quantify the extent that pre-existing knowledge of Latinate word parts and morphologically complex vocabulary differed among groups based on language origin. The identical instrument served as a posttest to measure the extent that direct instruction in morphological analysis resulted in change among the same groups after one semester of instruction. Two sections on both the pretest and posttest yielded a total of four distinct mean scores that formed the primary basis for comparison. Categorizing students within the college preparatory reading class based on language origin revealed distinctive strengths and weaknesses relative to group identity when learning Latin-based word parts and vocabulary. Results of a one-way fixed-factor analysis of variance, in conjunction with multiple comparison procedures, indicated that the Latin-based group performed the strongest. This group had the greatest mean score on all four measurements; however, only for the word part section of the pretest was the difference statistically significant. The non Latin-based group performed the poorest as evidenced by scoring the lowest on three of the four measures, with a statistically significant difference for the vocabulary pretest. Additionally, a disproportionately large number of students within the native English-speaking group had difficulty mastering word parts. Though the lower group mean was statistically significant for the word part section of the posttest, practical significance was not observable from the descriptive data. A follow-up frequency tabulation revealed a dichotomization within the native English speaking group between those who proceeded to master word parts and those who did not. Furthermore, results from a pretest/posttest comparison for each respective group indicated that all three groups made significant gains on both sections of the test instrument as a result of direct instruction in Latinate word parts and vocabulary. However, there was an incongruity between word part and vocabulary mastery as all three group means were markedly better on the word part section of the instrument. The results of this study suggest that college preparatory students, regardless of their language origin, enter higher education with limited knowledge of Latinate word parts and vocabulary. The results further suggest that students comprising the heterogeneously populated college preparatory reading class can profit from direct instruction in morphological analysis--regardless of language origin. Prior research has demonstrated that college-level content words tend to be morphologically complex, singular in meaning, and likely to be Latinate in origin. Reading is the salient skill utilized across the curriculum and often the primary means of content dissemination. Reading, in turn, is principally linked to the extent of one's vocabulary. Consequently, teaching morphologically complex vocabulary at the college preparatory level along with providing a working knowledge of morphemes can assist students toward college readiness.
Show less - Date Issued
- 2005
- Identifier
- CFE0000444, ucf:46384
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000444
- Title
- REMEDIATION OF HEAVY METAL CONTAMINATION IN SEDIMENTS: APPLICATION OF IN SITU TREATMENT UTILIZING EMULSIFIED LIQUID MEMBRANE AND ZERO-VALENT METAL TECHNOLOGIES.
- Creator
-
Maxwell, Deborah, Clausen, Christian, University of Central Florida
- Abstract / Description
-
Heavy metal contamination of soils, sediments and groundwater presents an ongoing source of hazardous and persistent environmental pollution. How best to remediate these contaminants is the impetus of continuing research efforts. Methods include containment, ex situ and in situ techniques. A successful in situ method utilizing a combination of emulsified liquid membranes, ELM, and zero-valent metal, ZVM, and bimetals has demonstrated impressive heavy metal reduction in 100 ppm solutions of Cd...
Show moreHeavy metal contamination of soils, sediments and groundwater presents an ongoing source of hazardous and persistent environmental pollution. How best to remediate these contaminants is the impetus of continuing research efforts. Methods include containment, ex situ and in situ techniques. A successful in situ method utilizing a combination of emulsified liquid membranes, ELM, and zero-valent metal, ZVM, and bimetals has demonstrated impressive heavy metal reduction in 100 ppm solutions of Cd, Cu, Ni, Pb, Cr and U. This promising in situ method has been employed by the Industrial Chemistry Laboratory at the University of Central Florida and it has demonstrated considerable success in treating several environmental threats. Contaminated soils, surfaces, sediments and groundwater with offending agents such as trichloroethene, polychorobiphenyls and heavy metals have been treated utilizing emulsified liquid membrane systems containing zero-valent iron or bimetal particles. In vial studies, lead spiked sediments have shown repeatable 60% removal of lead after seven days of treatment. A persistent pattern emerged at ten days whereupon remediation levels began to drop. The current study was established to determine the reason for the decline at ten days and beyond. Questions addressed: Does the formation of an impeding oxide layer diminish the remediation capacity of the iron/magnesium system? Does the emulsion reach a maximum capacity to withdraw the contaminant? Do the soil components or the soil structure interfere with the access to the contaminant? This study has yielded insight into the reasons emulsified liquid membrane systems containing zero-valent metals achieved maximum lead removal at day seven, and thereafter begin to lose their effectiveness. A three part study was implemented to address and to answer the three questions pertaining to the consistent pattern of diminishing remediation levels exhibited at day ten and beyond. Initially, from Study I results it appeared that the formation of an impeding oxide layer on the bi-metal which was inside the emulsion droplet and which plated or precipitated with the lead was not occurring at day ten. Results indicated that the iron/magnesium was still capable of removing lead. Furthermore, from Study II results the emulsion dose injected appeared adequate to remove the lead, meaning that the emulsion had not reached its maximum capacity for remediation. The emulsion dose was not a limiting factor. Lastly, Study III results seemed to indicate that the drop in remediation after day seven pertained to the soil structure. There appeared to be some merit to the idea that with aging of the sediment, the lead was diffusing and migrating to some inaccessible interior sites within the sediment particles. Additionally, indications from day ten and day fourteen delineated that a second emulsion dose injection might restore lead removal levels to approach those first observed at day seven and consequently be a useful field application. In order to explore the effectiveness of injecting a second dose of emulsion, another vial study was implemented. The typical pattern of observing sixty percent maximum lead removal at day seven was observed. In separate groups, a second injection of emulsion was added at day five, and then for another vial series, a second dose was added at day seven. The second emulsion dose treatment for either day five or day seven did not yield any increases in percent lead removal. Another theory emerged after viewing micrographs of recovered iron/magnesium compared with fresh ball-milled bimetal. In addition, scanning electron microscopy appeared to confirm the explanation that the emulsified zero-valent metal system might be compromised after day seven. This would lead to exposure of the iron/magnesium to the air and the elements. Corrosion of the bimetal might be occurring. With time, release of the plated or precipitated lead back into the sediment mixture could follow. The results of Study I had led to the conclusion that an impeding oxide layer had not formed; however, this conclusion may have been premature because the recovered iron/magnesium was exposed to lead solution in the vial study. Perhaps if the recovered iron/magnesium was inserted back into an emulsion and injected into lead spiked sediments the percent lead removed might give a more accurate picture of the iron/magnesium's capability to continue performing remediation. Remediation of sediments contaminated with lead is a complicated task because of the complex nature of sediment components. Emulsified liquid membranes utilizing zero-valent bimetals has repeatedly demonstrated impressive results at day seven; however, this treatment method is not without its limitations. Optimal results appear to be gained at day seven after emulsion injection. The bimetal and plated or precipitated lead must be removed at that point; otherwise the effective remediation of the contaminant is progressively reversed.
Show less - Date Issued
- 2007
- Identifier
- CFE0001786, ucf:47274
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001786
- Title
- An Evaluation Study of the Effectiveness of Using a Reaction-Based Process for Hydrazine Remediation.
- Creator
-
Oropeza, Cristina, Clausen, Christian, Yestrebsky, Cherie, Miles, Delbert, Elsheimer, Seth, Griffin, Timothy, University of Central Florida
- Abstract / Description
-
Hydrazine (HZ) and monomethylhydrazine (MMH) are used extensively as hypergolic propellants at Kennedy Space Center. These highly reactive fuels are considered highly toxic, and potentially carcinogenic. Consequently, the transport, handling, and disposal of hydrazines is strictly regulated to protect personnel and the environment. Currently, KSC generates large volumes of hydrazine-laden wastewater for disposal. This waste is contained and shipped on public highways for subsequent disposal...
Show moreHydrazine (HZ) and monomethylhydrazine (MMH) are used extensively as hypergolic propellants at Kennedy Space Center. These highly reactive fuels are considered highly toxic, and potentially carcinogenic. Consequently, the transport, handling, and disposal of hydrazines is strictly regulated to protect personnel and the environment. Currently, KSC generates large volumes of hydrazine-laden wastewater for disposal. This waste is contained and shipped on public highways for subsequent disposal by incineration presenting a potentially catastrophic threat to the environment and the general public in the event of an accidental release. Other existing remediation methods include oxidative and reductive pathways as well as biodegradation in fixed film reactors. Each of these methods has associated drawbacks and limitations that make them unsuitable for industrial use. Recently, hydrazine neutralization by reaction with alpha-ketoglutaric acid (AKGA) to form the stabilized pyridazine derivatives PCA and mPCA has been explored. The applicability of this technique for use at KSC has been established and procedural considerations for implementation have been addressed.Experimental evidence based on worst case scenario decontamination processing simulations and reaction characterization has suggested that AKGA can cost effectively function as a drop-in replacement for current neutralizers with minimal modification to existing infrastructure and operating procedures. Further work will be necessary to satisfy permitting requirements and verify that the reaction product stream is non-hazardous in light of limited toxicity data.
Show less - Date Issued
- 2011
- Identifier
- CFE0004148, ucf:49060
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004148
- Title
- Investigation of a Novel Magnesium and Acidified Ethanol System for the Degradation of Persistent Organic Pollutants.
- Creator
-
Maloney, Phillip, Yestrebsky, Cherie, Clausen, Christian, Elsheimer, Seth, Frazer, Andrew, Quinn, Jacqueline, University of Central Florida
- Abstract / Description
-
For centuries chemists have sought to improve humankind's quality of life and address many of society's most pressing needs through the development of chemical processes and synthesis of new compounds, often with phenomenal results. Unfortunately, there also are many examples where these chemicals have had unintended, detrimental consequences that are not apparent until years or decades after their initial use. There are numerous halogenated molecules in this category that are globally...
Show moreFor centuries chemists have sought to improve humankind's quality of life and address many of society's most pressing needs through the development of chemical processes and synthesis of new compounds, often with phenomenal results. Unfortunately, there also are many examples where these chemicals have had unintended, detrimental consequences that are not apparent until years or decades after their initial use. There are numerous halogenated molecules in this category that are globally dispersed, resistant to natural degradation processes, bioaccumulative, and toxic to living organisms. Chemicals such as these are classified as persistent organic pollutants (POPs), and due to their negative environmental and health effects, they require safe, effective, and inexpensive means of remediation.This research focuses on the development and optimization of a reaction matrix capable of reductively dehalogenating several POPs. Initial experiments determined that powdered magnesium and 1% V/V acetic acid in absolute ethanol was the most effective system for degrading polychlorinated biphenyl (PCB), an extraordinarily recalcitrant environmental contaminant. Further studies showed that this matrix also was capable of degrading polychlorinated dibenzo-p-dioxins (PCDDs), polybrominated diphenyl ethers (PBDEs), and four organochlorine pesticides (OCPs); dieldrin, heptachlor, heptachlor epoxide, and chlordane. During this phase of testing, field samples contaminated with chlordane were washed with ethanol and this ethanol/chlordane solution was degraded using the same reaction matrix, thereby demonstrating this technology's potential for (")real-world(") remediation projects. Finally, a set of experiments designed to provide some insight into the mechanism of dechlorination seems to indicate that two distinct processes are necessary for degradation to occur. First, the passivated outer layer of the magnesium must be removed in order to expose the zero-valent magnesium core. Next, an electron is transferred from the magnesium to the target molecule, causing the cleavage of the halide bond and the subsequent abstraction of either a hydrogen or proton from a solvent molecule. It is anticipated that an understanding of these fundamental chemical processes will allow this system to be tailored to a wide range of complex environmental media.
Show less - Date Issued
- 2013
- Identifier
- CFE0005109, ucf:50723
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005109
- Title
- A Correlational Study of Emerging Modalities of Developmental Education and Learning Styles in a Florida State College.
- Creator
-
Britt, John, Cox, Dr. Thomas, King, Kathy (Kathleen), Vitale, Thomas, Penfold Navarro, Catherine, University of Central Florida
- Abstract / Description
-
Developmental education course modalities in Florida were drastically changed in 2013 with the passage of Senate Bill 1720. These courses can no longer be offered in a traditional 16-week format as other postsecondary courses are offered. Developmental education courses must now be offered in a compressed, contextualized, or corequisite instruction modality; or direct enrollment into a gateway course (1720-Education, 2013). This changes the student's experience in the courses. This research...
Show moreDevelopmental education course modalities in Florida were drastically changed in 2013 with the passage of Senate Bill 1720. These courses can no longer be offered in a traditional 16-week format as other postsecondary courses are offered. Developmental education courses must now be offered in a compressed, contextualized, or corequisite instruction modality; or direct enrollment into a gateway course (1720-Education, 2013). This changes the student's experience in the courses. This research was framed by Kolb's experiential learning theory, which states that people learn through their experiences (Kolb, 1984). Chi-Square correlational tests were conducted to examine the relationship between students' learning types and their final grades in an accelerated developmental math course and in a combined developmental math course. The results indicate no statistically significant relationships between the variables in both modalities of developmental math. Furthermore, students were surveyed on their preferences of the developmental math modalities. The results showed positive preferences toward both modalities of developmental math. With the limited amount of research in the area of developmental math modalities, this research helps to further understand the area and provides a basis for future research.
Show less - Date Issued
- 2016
- Identifier
- CFE0006445, ucf:51473
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006445
- Title
- Magnesium and Acidified Ethanol Based Treatment Systems for the Extraction and Dechlorination of Polychlorinated Biphenyls from Contaminated Oils, Paints, and Soils.
- Creator
-
Novaes-Card, Simone, Yestrebsky, Cherie, Clausen, Christian, Elsheimer, Seth, Frazer, Andrew, Duranceau, Steven, University of Central Florida
- Abstract / Description
-
Polychlorinated biphenyls (PCBs) are a class of environmentally persistent halogenated organic compounds that were once used as stabilizers to improve the properties of a variety of materials such as lubricants, heat transfer fluids, paints, and caulking materials. PCBs are also capable of migration through processes such as spillage into soils, leaching into groundwater, and volatilization into the atmosphere. Although banned in 1979 over health concerns, PCBs persist in these materials to...
Show morePolychlorinated biphenyls (PCBs) are a class of environmentally persistent halogenated organic compounds that were once used as stabilizers to improve the properties of a variety of materials such as lubricants, heat transfer fluids, paints, and caulking materials. PCBs are also capable of migration through processes such as spillage into soils, leaching into groundwater, and volatilization into the atmosphere. Although banned in 1979 over health concerns, PCBs persist in these materials to this day because they are resistant to biotic degradation and natural weathering processes. The wide variety of contaminated materials means that many existing treatment options cannot be used across all media. This research focuses on the adaptation of a reductive dehalogenation system for dechlorination of PCBs from machine oils, paints, sludges, and soils. The system utilizes magnesium, glacial acetic acid, and ethanol in order to remove the chlorine atoms from the biphenyl backbone, which is less toxic and can be broken down biotically.A treatment plan was devised for machine oil contaminated with PCBs, involving sorption of PCBs onto a column of super activated alumina followed by desorption into hexane and treatment of the hexane with magnesium and acidified ethanol to dechlorinate the PCBs. In a small-scale study, 98.5% of PCBs from an oil sample were sorbed to the column, and the PCBs that were subsequently desorbed were dechlorinated to below detectable levels within one day of magnesium and acidified ethanol treatment. Information from small-scale studies was used to design larger sorption columns intended for use at a field site.A field study was conducted to compare the effectiveness of two different treatment system pastes at removing PCBs from painted surfaces. These pastes were formulated with bulking and viscosity control agents in order to cling to vertical surfaces, and contained either acidified ethanol and magnesium (Activated Metal Treatment System, AMTS) or acidified ethanol only (Non-Metal Treatment System, NMTS). AMTS was capable of 64.8% average removal of PCBs from paint, while NMTS demonstrated 89.5% average removal but required a second step to dechlorinate the extracted PCBs. This system allows for treatment of surfaces without demolishing the structure. AMTS was also studied for in situ dechlorination of PCBs in soils, and NMTS enclosed in a polyethylene barrier was studied for extraction of PCBs from sludges.A two-step system was devised for the ex situ treatment of PCB-contaminated soils. Solvent extraction with ethanol or an ethanol/ethyl lactate cosolvent is followed by dechlorination using magnesium and glacial acetic acid. Studies included the optimization of extraction solvent, cosolvent ratio, cost, and reuse of magnesium or extraction solvent. Surface analysis of magnesium particles used in dechlorination showed a precipitate occluding part of the surface, which was thought to be a combination of magnesium ethoxide and magnesium hydroxide. This precipitate is thought to come from the reaction of magnesium ethoxide formed during the PCB dechlorination process with pore water extracted from the soil.
Show less - Date Issued
- 2013
- Identifier
- CFE0005222, ucf:50630
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005222
- Title
- Remediation of Polychlorinated Biphenyl (PCB) Contaminated Building Materials Using Non-metal and Activated Metal Treatment Systems.
- Creator
-
Legron-Rodriguez, Tamra, Yestrebsky, Cherie, Clausen, Christian, Elsheimer, Seth, Sigman, Michael, Chopra, Manoj, Quinn, Jacqueline, University of Central Florida
- Abstract / Description
-
PCBs are recalcitrant compounds of no known natural origin that persist in the environment despite their ban by the United States Environmental Protection Agency in 1979 due to negative health effects. Transport of PCBs from elastic sealants into concrete, brick, and granite structures has resulted in the need for a technology capable of removing these PCBs from the materials. This research investigated the use of a nonmetal treatment system (NMTS) and an activated metal treatment system ...
Show morePCBs are recalcitrant compounds of no known natural origin that persist in the environment despite their ban by the United States Environmental Protection Agency in 1979 due to negative health effects. Transport of PCBs from elastic sealants into concrete, brick, and granite structures has resulted in the need for a technology capable of removing these PCBs from the materials. This research investigated the use of a nonmetal treatment system (NMTS) and an activated metal treatment system (AMTS) for the remediation and degradation of PCBs from concrete, brick, and granite affixed with PCB-laden caulking. The adsorption of PCBs onto the components of concrete and the feasibility of ethanol washing were also investigated.NMTS is a sorbent paste containing ethanol, acetic acid, and fillers that was developed at the University of Central Florida Environmental Chemistry Laboratory for the in situ remediation of PCBs. Combining NMTS with magnesium results in an activated treatment system used for reductive dechlorination of PCBs. NMTS was applied to laboratory-prepared concrete as well as field samples by direct contact as well as by a novel sock-type delivery. The remediation of PCBs from field samples using NMTS and AMTS resulted in a 33-98% reduction for concrete, a 65-70% reduction for brick, and an 89% reduction in PCB concentration for granite. The limit of NMTS for absorption of Aroclor 1254 was found to be roughly 22,000 mg Aroclor 1254 per kg of treatment system or greater. The activated treatment system resulted in a 94% or greater degradation of PCBs after seven days with the majority of degradation occurring in the first 24 hours. The adsorption of PCBs to individual concrete components (hydrated cement, sand, crushed limestone, and crushed granite) was found to follow the Freundlich isotherm model with greater adsorption to crushed limestone and crushed granite compared to hydrated cement and sand. Ethanol washing was shown to decrease the concentration of laboratory-prepared concrete by 68% and the concentration of PCBs in the ethanol wash were reduced by 77% via degradation with an activated magnesium system.
Show less - Date Issued
- 2013
- Identifier
- CFE0005197, ucf:50625
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005197