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Using Transition State Theory to Understand the Kinetics for the Gas-Phase Synthesis of Ammonia
Get PDFTo identify the rate-determining step and the most stable transition state for the Haber-Bosch synthesis of gas-phase ammonia, electronic structure calculations for the reactants (N2, H2, NNH2, H2NNH2, HNNH3), intermediates, and transition states were found using the program GAMESS and the basis sets 6-31G*, 6-311G**, and STO-3G (1). The basis set 6-31G* revealed N2(g) + 3H2(g) ⇌ TS1 ⇌ NNH2(g)+ 2H2(g) as the rate-determining step because it had the smallest equilibrium constant (Keq) of 4.2085*10-36. The reaction coordinate diagram showed the most stable transition state was TS4 from the step HNNH3(g) + H2(g) ⇌ TS4 ⇌ 2NH3(g), which had the smallest change in complex enthalpy (ΔHc) of -17.058 kJ/mol. Finally, comparing the resulting changes in reaction Gibbs free energy (ΔGrxn’s), enthalpies (ΔHrxn’s) and entropies (ΔSrxn’s) to values calculated from literature revealed that 6-31G* was the most accurate basis set with a ΔHrxn of -9.6639*101 kJ/mol which had an error of 5.2712*100 % compared to the literature value of -9.1800*101 kJ/mol, ΔSrxn of -6.7433*101 J/mol*K with an error of -6.5960*101 % compared to the literature value of -1.9810*102 J/mol*K, and ΔGrxn of -7.6534*104 J/mol with an error of 1.3379*102 % compared to the literature value of -3.2736*104 kJ/mol (2). Though STO-3G had lower errors of -9.8536*10-1 % and -1.4340*102 % for ΔSrxn and ΔGrxn compared to 6-311G**’s errors of -6.5945*101 % and 2.0873*102 %, it had enthalpies for the forward and reverse equilibrium reactions that were so large that Keq for step NNH2(g) + 2H2(g) ⇌ H2NNH2(g) + H2(g) could not be calculated. STO-3G assumes that all orbitals are spherical which results in its inability to describe orbitals that participate in bonding. This assumption makes the basis set unreliable when used to find the Keq‘s for each step. Both 6-31G* and 6-311G** are ideal basis sets for such an experiment because they are polarization sets created to describe electron distribution between bonds
“Every Nation Except Our Own”: The Social Gospel, Anti-Immigrant Sentiments, and U.S. Foreign Policy
Get PDFThis thesis concerns the social gospel, a liberal Protestant movement that enjoyed its heyday in the late 19th and early 20th centuries. The thesis argues that the movement’s two most prominent figures, Washington Gladden and Walter Rauschenbusch, expressed an antipathy toward immigrants and a paternalistic attitude toward foreign nations and cultures. These attitudes then laid the foundation for contemporary anti-immigrant sentiments and US foreign policy. Gladden and Rauschenbusch’s rhetoric contains sentiments which act as a precursor to various elements of American exceptionalism, from missionary activity abroad to liberal attitudes toward the Middle East after 9/11. These links have not been explored extensively in previous literature, and the thesis aims to fill this gap
Using Machine Learning to Measure Political Polarization on Social Media
Get PDFPolarization in the political sphere, seen through combative communication and stalemate, may impose negative social impacts on the population. Attempting to measure political polarization in the masses through self-reported surveys and interviews can present response biases of social desirability. The classification of thought freely written online allows political polarization to be measured in an impartial manner. Reddit is one application that enables users to share opinions and create discussions anonymously; this text can be used to measure the political climate at any given time. Disagreement has grown over the perceived level of polarization in our society. The purpose of my research is to measure the degree of political polarization over time by collecting and classifying threads of dialogue within political communities on Reddit.
I utilized Reddit APIs to gather threads of text from multiple subreddit communities online. I recruited a team of evaluators to hand-annotate the threads for polarization. Then, I created a machine learning classifier to predict whether a thread posted on Reddit is polarized or not. I trained a multilayer perceptron on the hand-tagged data. Depending on parameter choices, the classifier performed with an accuracy of between 75% and 80% on an independent test set. There does not appear to be a strong pattern indicating a rise in polarization overall on Reddit during the period 2008 to the present. However, when looking at some of the subreddits individually, there is evidence of an increase in polarization
Asymmetric Synthesis of the Oxidative Metabolites of Di(2-ethylhexyl) Phthalate and Analysis of Binding with Peroxisome Proliferator-Activated Receptors
Get PDFDi(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer that is known to be an endocrine disrupting chemical (EDC). Exposure to its primary metabolite, mono(2-ethylhexyl) phthalate (MEHP) and other secondary oxidative metabolites is associated with adverse health effects in vivo which are linked to interactions with nuclear hormone receptors such as peroxisome-proliferator activated receptors (PPARs). Although these molecules are chiral, differences in the toxicity of each stereoisomer are not well studied. By synthesizing the enantiomers of these molecules and testing their affinity for PPARγ by thermal shift assay (TSA), potential differences in binding affinity of each form can be determined. Enzymatic resolution of racemic 2-ethyl-1-hexanol by a combination of non-immobilized and immobilized Amano Lipase species gave enantiomerically pure primary alcohols. These alcohols were esterified with phthalic anhydride, yielding (R)-MEHP (68% yield), (S)-MEHP (68% yield), (R,R)-DEHP (34% yield), (R,S)-DEHP (13 % yield), and (S,S)-DEHP (94 % yield). Thereafter, racemic synthesis of three secondary oxidative metabolites, mono-[2-(carboxymethyl)hexyl]phthalate (2cx-MMHP), mono-(2-ethyl-5-carboxypentyl)phthalate (5cx-MEPP), and mono-(2-ethyl-5-oxohexyl)phthalate (5oxo-MEHP), was completed in four steps with yields of 11%, 5.7%, and 11%, respectively. Preliminary TSA results show the need for further optimization of protein:dye ratios and evaluation of the PPARγ solution used for unwanted binding with pre-existing ligands. Ultimately, completed asymmetric synthesis of the secondary oxidative metabolites and evaluation of all products by TSA, or other measure of protein-ligand stability, will serve as a means for determining if a chiral component to phthalate toxicity is present within DEHP metabolism
Directing Lemons Lemons Lemons Lemons Lemons
No full textIn Fall 2023, I completed my senior project in the theatre major by directing the play Lemons Lemons Lemons Lemons Lemons in Studio 115, the student-run black box theatre. My blog contains my research documents, rehearsal logs, journals, and production photos. Alongside being directed by myself, it was acted, designed, and produced by UMW students. This project was designed as a culmination of my coursework as a directing student and gives me the opportunity to engage fully in the production and rehearsal processes for a full-length play
A Novel Generative Paradigm for Carnatic Rhythmic Composition
Get PDFMathematical structures are deeply embedded in the aesthetics of South Indian Carnatic music. Kōrvais, which are rhythmic compositions performed in triplets in various parts of a concert, are the culmination of this mathematical aesthetic. Each kōrvai has two parts, the first called the pūrvārdha and the second called the uttarārdha, both based on mathematical structures that are aesthetically acceptable according to certain constraints. These structures have evolved traditionally and can accommodate most rhythmic requirements. However, the traditional methods are inadequate in addressing certain specialized constraints. Therefore, this article revisits rhythmic composition through conceptualization of newer rhythmic patterns and use of algorithmic approaches to determine the components of the kōrvai. Specifically, we systematically address the need for newer rhythmic compositional paradigms in Carnatic music by first introducing the fundamentals of Carnatic rhythmic compositional theory and practice via a collection of mathematical models. We subsequently highlight the limitations of traditional methods and outline the requirements of newer approaches, which will be exemplified through four new kōrvais. We further exemplify, via video-recorded performances, how the proposed approach can be easily extended beyond percussion solos to Carnatic vocal presentations. The final section considers how these algorithmic approaches to Carnatic rhythmic composition could also be useful in other, non-Carnatic systems of music, with newly composed examples for illustration
Declining Rural Influence in Virginia Politics
No full textThis chapter traces the declining influence of rural Virginia through a comparison of statewide election results nearly two decades apart: 2001 and 2020. The authors compare Mark Warner’s 2001 election as governor, which included significant rural support, and his 2020 senate campaign, which did not. Although both contests involved victorious statewide campaigns by the same Democratic candidate, the political and cultural changes that have taken place in Virginia over this period could suggest something comparable to two different states: the Virginia of 2001 and the Virginia of 2020. As this chapter shows, the Virginia political environment of 2020 was far different from the environment of 2001—and those differences were not advantageous for the advancement of rural interests
The Ethics of Care and the U.S. Covid-19 Pandemic Response
Get PDFThroughout the pandemic, many conservatives like President Donald Trump lacked emotional sensitivity in regards to the millions of lives affected by COVID-19. They believed themselves to be too strong for the virus to take them down, and viewed those who wore masks as weak and afraid. Unlike Democrats, Republican governors entrusted their constituents to take necessary safety precautions and avoided statewide mask mandates, vaccine requirements, and lockdowns. Their policies and rhetoric demonstrated the overlap in harmful masculine traits and the conservative values of self-sufficiency and independence. Using a case study method, this paper analyzes the role of gender in a governor’s pandemic response by comparing women and men of the same party, and the role of partisanship by comparing Republicans to Democrats of the same gender. By applying Carol Gilligan\u27s Ethics of Care theory to each governor\u27s response, this paper concludes with the understanding that (1) Care Ethics are essential in matters of public health; (2) Democrats and women tend to base their responses to COVID-19 using an ethic of care over an ethic of justice, but not exclusively; (3) Gender and partisanship are critical factors in determining ethical behavior during the pandemic, but so is personal tragedy, personal suffering, and caregiving experience; and (4) Justice Ethics and Care Ethics are not incompatible with each other and should both be used in matters of public health
Effectiveness of Virginia Teacher Preparation Programs
Get PDFThe perspective of first-year teachers is valuable in identifying the ways in which preparation programs are successfully educating their student teachers. This qualitative study investigates the effectiveness of university-based teacher preparation programs accredited by the Commonwealth of Virginia. Specifically, this study is attempting to gain a better understanding of how the knowledge and skills of novice teachers were efficiently developed in the areas of differentiation, multiculturalism, classroom management, and content knowledge as well as how mentorship through field experience contributes to their growth. To answer the research question, seven interviews were analyzed from in-state, first-year teachers that recently graduated from a Virginia education program. Findings indicated that the evaluation of Virginia programs is consistent with average ratings across the United States except for higher rates of preparation in multiculturalism. It is also recommended that programs instruct using frequent field experience in conjunction with courses
How Rhythm Affects Prosody
Get PDFMusic interventions and how they benefit reading fluency have been researched, but there is more to be done in discovering the benefits of rhythm and prosody. This quantitative research study looked at how rhythm-based interventions affect student prosody in a second-grade classroom. Data were gathered from a music experience survey, a prosody pre-assessment, and a prosody post-assessment. The music intervention in this study involved three rhythm-based interventions called “DeeDee games.” This research analyzed and compared the growth between the prosody pre-and post-assessments and the results between students with musical backgrounds and students without musical backgrounds. This study found insufficient evidence to support that there is any significant growth after completing the rhythm interventions