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Assessing Student Perceptions in Short Research Experiences and Course Research Experiences in Undergraduate Biology Laboratories

This study examined students' perception between short research experiences (SRE) courses and full-semester course research experiences (CRE) using the Persistence in the Sciences (PITS) survey and the interview questionnaire. The study also aimed to correlate the influence of student's demographic as a predictive indicator for Project Ownership Scores (POS) and Quantitative Literacy (QL) score means. The three courses studied at the University of North Texas were Biology for Science Majors Lab… more

Date: August 2022

Creator: Alberts, Arland Dulcey

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Allowing Students to Have VOICES (Voluntary Options in Chemical Education Schedules) in General Chemistry I

The purpose of this investigation (a quasi-experimental design called a non-equivalent design group (NEDG)) was to determine if allowing students in a science majors general Chemistry I course the choice in establishing the due dates that their homework was due to the instructor would improve course averages. This study covered two semesters with a total of 288 students participating with n = 158 in the fall and n = 130 in the spring. The students self-selected the homework group, VOICES, tha… more

Date: December 2018

Creator: Ford, Robyn Lynn

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Teaching First-Semester General Chemistry Using 3D Video Games following an Atoms First Approach to Chemistry

The unified learning model (ULM) focuses on students' engagement, motivation, prior knowledge, and working memory. This study employs the use of video games to assess students' learning through a 3D chemistry gaming environment. In this human-subjects research, students carried out missions and applied reasoning to solve problems appropriate for general chemistry content. For learning to occur, students must be engaged and motivated as stated in the ULM. Learning cannot necessarily be accomplis… more

Date: August 2018

Creator: Jenkins, Dave A

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Using the Abraham Solvation Parameter Model to Predict Solute Transfer into Various Mono- and Multi-Functional Organic Solvents

The Abraham Solvation Parameter Model (ASPM) is a linear, free-energy relationship that can be used to predict various solute properties based on solute-solvent interactions. The ASPM has been used to predict log (K or Cs,organic/Cs,gas) values, as well as log (P or Cs,organic/Cs,water) values for solute transfer into the following organic solvents: 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-isopropoxyethanol and 2-butoxyethanol. The derived log (K or Cs,organic/Cs,gas) correlations… more

Date: May 2018

Creator: Hart, Erin F

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

First-Semester General Chemistry Curriculum Comparison of Student Success on ACS Examination Questions Grouped by Topic Following an Atoms First or Traditional Instructional Approach

This study uses the ACS first-term general chemistry exam to determine if one curriculum approach is more effective in increasing student success than the other based on their performance on the ACS exam. Two chemistry curriculum approaches were evaluated in this study; the traditional curriculum (TC) and the Atoms First (AF) approach. The sample population was first-semester general chemistry students at Collin College in Frisco, TX. An independent sample t-test was used to determine if there… more

Date: August 2014

Creator: Molina, Cathy D.

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

A Vygotskian Analysis of Preservice Teachers’ Conceptions of Dissolving and Density

The purpose of this study was to examine the content knowledge of 64 elementary preservice teachers for the concepts of dissolving and density. Vygotsky’s (1987) theory of concept development was used as a framework to categorize concepts and misconceptions resulting from evidences of preservice teacher knowledge including pre/post concept maps, writing artifacts, pre/post face-to-face interviews, examination results, and drawings. Statistical significances were found for pre- and post-concep… more

Date: May 2014

Creator: Shaker elJishi, Ziad

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Impact of Texas High School Science Teacher Credentials on Student Performance in High School Science

A study was conducted to determine the relationship between the credentials held by science teachers who taught at a school that administered the Science Texas Assessment on Knowledge and Skills (Science TAKS), the state standardized exam in science, at grade 11 and student performance on a state standardized exam in science administered in grade 11. Years of teaching experience, teacher certification type(s), highest degree level held, teacher and school demographic information, and the percen… more

Date: August 2012

Creator: George, Anna Ray Bayless

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Incorporating Electrochemistry and X-ray Diffraction Experiments Into an Undergraduate Instrumental Analysis Course

Experiments were designed for an undergraduate instrumental analysis laboratory course, two in X-ray diffraction and two in electrochemistry. Those techniques were chosen due their underrepresentation in the Journal of Chemical Education. Paint samples (experiment 1) and pennies (experiment 2) were characterized using x-ray diffraction to teach students how to identify different metals and compounds in a sample. in the third experiment, copper from a penny was used to perform stripping analyses… more

Date: May 2012

Creator: Molina, Cathy

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Relationships of Approaches to Studying, Metacognition, and Intellectual Development of General Chemistry Students

This study investigated approaches to studying, intellectual developments, and metacognitive skills of general chemistry students enrolled for the spring 2011 semester at a single campus of a multi-campus community college. the three instruments used were the Approaches and Study Skills Inventory for Students (ASSIST), the Learning Environment Preferences (LEP), and the Executive Process Questionnaire (EPQ). the subjects were 138 students enrolled in either general chemistry 1 or 2. the resu… more

Date: May 2012

Creator: Egenti, Henrietta N.

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Characterization of Novel Solvents and Absorbents for Chemical Separations

Predictive methods have been employed to characterize chemical separation mediums including solvents and absorbents. These studies included creating Abraham solvation parameter models for room-temperature ionic liquids (RTILs) utilizing novel ion-specific and group contribution methodologies, polydimethyl siloxane (PDMS) utilizing standard methodology, and the micelles cetyltrimethylammonium bromide (CTAB) and sodium dodecylsulfate (SDS) utilizing a combined experimental setup methodology with … more

Date: May 2011

Creator: Grubbs, Laura Michelle Sprunger

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Effects of Using Logic and Spatial Cybergames to Improve Student Success Rates in Lower-Division Chemistry Courses

A study was conducted to investigate the relationships between cybergaming treatment groups and the control group (N = 99: ncontrol = 8; nlogic = 29; nspatial = 30; ncombination = 32) with success in the organic chemistry I course as measured by achievement over a 10-week period. The treatment groups included logic training, spatial training, and combination logic-spatial training. Students' ability was measured by pre/post exams using the Group Assessment of Logical Thinking (GALT) to measure … more

Date: May 2011

Creator: Manrique, Carissa Janice

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Affordances of Instrumentation in General Chemistry Laboratories

The purpose of this study is to find out what students in the first chemistry course at the undergraduate level (general chemistry for science majors) know about the affordances of instrumentation used in the general chemistry laboratory and how their knowledge develops over time. Overall, students see the PASCO system as a useful and accurate measuring tool for general chemistry labs. They see the probeware as easy to use, portable, and able to interact with computers. Students find that the … more

Date: August 2010

Creator: Sherman, Kristin Mary Daniels

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Examining and Characterizing Changes in First Year High School Chemistry Curricula

Many students currently entering college are able to solve mathematical problems but often do not understand the chemistry concepts underlying their calculations. High school chemistry teachers from Texas and the United States (US) were surveyed as to what topics they teach in their chemistry classes. A subset of Texas teachers was also interviewed about their instruction. The survey indicated that less-experienced Texas teachers are omitting a number of topics from their chemistry instruction,… more

Date: August 2010

Creator: Holley, Kerry Kathleen McGee

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Homework versus daily quizzes: The effects on academic performance within high school pre-AP chemistry.

This research proposed to evaluate whether homework or daily quizzes were better for academic success within high-school pre-AP chemistry or if differences in the two methods were detectable. The study involved two years of data where homework was assigned and graded and one year of data where homework was suggested but daily quizzes provided the assessment. The mean of each of the unit tests were evaluated and t-tests were calculated. The results showed that over two-thirds of the units had st… more

Date: August 2010

Creator: King, Jo Laurie Marushia

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Podcast Effectiveness as Scaffolding Support for Students Enrolled in First-Semester General Chemistry Laboratories

Podcasts covering essential first-semester general chemistry laboratory techniques and central concepts that aid in experimental design or data processing were prepared and made available for students to access on an as-needed basis on iPhones- or iPod touches-. Research focused in three areas: the extent of podcast usage, the numbers and types of interactions between instructors and research teams, and student performance on graded assignments. Data analysis indicates that the podcast treatmen… more

Date: August 2010

Creator: Powell, Mary Cynthia Barton

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

The Pure Rotational Spectra of Diatomics and Halogen-Addition Benzene Measured by Microwave and Radio Frequency Spectrometers

Two aluminum spherical mirrors with radii of 203.2 mm and radii of curvature also of 203.2 mm have been used to construct a tunable Fabry-Perót type resonator operational at frequencies as low as 500 MHz. The resonator has been incorporated into a pulsed nozzle, Fourier transform, Balle-Flygare spectrometer. The spectrometer is of use in recording low J transitions of large asymmetric molecules where the spectra are often greatly simplified compared to higher frequency regions. The resonators u… more

Date: August 2010

Creator: Etchison, Kerry C.

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Interaction of learning approach with concept integration and achievement in a large guided inquiry organic class.

A study was conducted to investigate the relationship of students' concept integration and achievement with time spent within a topic and across related topics in a large first semester guided inquiry organic chemistry class. Achievement was based on evidence of algorithmic problem solving; and concept integration was based on demonstrated performance explaining, applying, and relating concepts to each other. Twelve individual assessments were made of both variables over three related topics - … more

Date: August 2009

Creator: Mewhinney, Christina

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Comparison of Homework Systems (Four Web-Based) used in First-Semester General Chemistry

Web-based homework systems are becoming more common in general chemistry as instructors face ever-increasing enrollment. Yet providing meaningful feedback on assignments remains of the utmost importance. Chemistry instructors consider completion of homework integral to students' success in chemistry, yet only a few studies have compared the use of Web-based systems to the traditional paper-and-pencil homework within general chemistry. This study compares the traditional homework system to four … more

Date: May 2009

Creator: Belland, Joshua

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Predicting Chemical and Biochemical Properties Using the Abraham General Solvation Model

Several studies were done to illustrate the versatillity of the Abraham model in mathematically describing the various solute-solvent interactions found in a wide range of different chemical and biological systems. The first study focused on using the solvation model to construct mathematical correlations describing the minimum inhibitory concentration of organic compounds for growth inhibition towards the three bacterial strains Porphyromonas gingivalis, Selenomonas artemidis, and Streptococc… more

Date: May 2009

Creator: Mintz, Christina

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Synthesis, characterization, and kinetics of isomerization, C-H and P-C bond activation for unsaturated diphosphine-coordinated triosmium carbonyl clusters.

Substitution of MeCN ligands in the activated cluster Os3(CO)10(MeCN)2 by the unsaturated diphosphine ligands (Z)-Ph2PCH=CHPPh2 (cDPPEn) or 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) proceeds rapidly at room temperature to furnish the ligand-bridged cluster 1,2-Os3(CO)10(P-P) (P-P represents cDPPEn or bpcd). Heating 1,2-Os3(CO)10(P-P) leads to the formation of the thermodynamically more stable chelating isomer 1,1-Os3(CO)10(P-P). Each compound of Os3(CO)10(P-P) has been characte… more

Date: May 2008

Creator: Wu, Guanmin

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Synthesis and characterization of diphosphine ligand substituted osmium and ruthenium clusters.

The kinetics for the bridge-to-chelate isomerization of the dppe ligand in H4Ru4(CO)10(dppe) have been investigated by UV-vis and NMR spectroscopies over the temperature range of 308-328 K. The isomerization of the ligand-bridged cluster 1,2-H4Ru4(CO)10(dppe) was found to be reversible by 31P NMR spectroscopy, affording a Keq = 15.7 at 323 K in favor of the chelating dppe isomer. The forward (k1) and reverse (k-1) first-order rate constants for the reaction have been measured in different sol… more

Date: August 2007

Creator: Kandala, Srikanth

Item Type: Thesis or Dissertation

Partner: UNT Libraries

Diphosphine Ligand Substitution in H4Ru4(CO)12: X-ray Diffraction Structures and Reactivity Studies of the Diphosphine Substituted Cluster Products

The tetraruthenium cluster H4Ru4(CO)12 has been studied for its reactivity with the unsaturated diphosphine ligands (Z)-Ph2PCH=CHPPh2, 4,5-bis (diphenylphosphino)-4-cyclopenten-1,3-dione, bis(diphenyphosphino)benzene and 1,8- bis(diphenyl phosphino)naphthalene under thermal, near-UV photolysis, and Me3NO-assisted activation. All three cluster activation methods promote loss of CO and furnish the anticipated substitution products that possess a chelating diphosphine ligand. Clusters 1, 2, 3 and … more

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Date: December 2006

Creator: Kandala, Srikanth

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

General Chemistry Topic Coverage (GCTC) comparison between community colleges and universities in the United States.

This study is based on survey responses of 224 general chemistry instructors at United States (U.S.) community colleges and universities representing 46 states. The mean values of General Chemistry Topic Coverage (GCTC) score, developed by this researcher specifically for this dissertation study as a measure of course content, were statistically analyzed. The aim of this study is to answer five research questions: (a) Is there a difference in mean GCTC scores between U.S. community colleges and… more

Date: December 2006

Creator: El-Ashmawy, Amina Khalifa

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Synthesis and Characterization of 2,3-Dichloropyrrolo[1,2-a]benzimidazol-1-one and Its Methylthiol Derivatives

Condensation of 2,3-dichloromaleic anhydride and o-phenylenediamine in refluxing toluene affords the three compounds 2,3-dichloro-N-o-C6H4(NH2)maleimide (1), N,N¢-o-C6H4-bis(2,3-dichloromaleimide) (2), and 2,3-dichloropyrrolo[1,2-a]benzimidazol-1-one (3), with compound 1 as the major product. Repeating the same reaction in the presence of added PTSA furnishes compound 3 as the major product. Treatment of 3 with methylthiol in the presence of pyridine affords monosulfide compounds 2-chloro-3-met… more

Date: May 2006

Creator: Wu, Guanmin

Item Type: Thesis or Dissertation

Partner: UNT Libraries