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Halogenated 2-Oxetanones

Description: The purpose of this investigation is threefold: (1) to examine in detail the cycloaddition of halogenated ketenes and carbonyl compounds, (2) to study the decarboxylation of the resulting halogenated 2-oxetanones,and (3) to investigate the effect of halogens in the halogenated 2-oxetanones on the nucleophilic addition reaction.
Date: May 1973
Creator: Patel, Arvind D.
Item Type: Refine your search to only Thesis or Dissertation
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N-Heterocyclic Carbenes of the Late Transition Metals: A Computational and Structural Database Study

Description: A computational chemistry analysis combined with a crystallographic database study of the bonding in late transition metal N-heterocyclic carbene (NHC) complexes is reported. The results illustrate a metal-carbon bond for these complexes, approximately 4% shorter than that of a M-C single bond found in metal alkyl complexes. As a consequence of this result, two hypotheses are investigated. The first hypothesis explores the possibility of multiple-bond character in the metal-carbon linkage of t… more
Date: May 2005
Creator: Baba, Eduard
Item Type: Refine your search to only Thesis or Dissertation
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High-Energy, Long-Lived Charge-Separated States via Molecular Engineering of Triplet State Donor-Acceptor Systems

Description: Molecular engineering of donor-acceptor dyads and multimodular systems to control the yield and lifetime of charge separation is one of the key goals of artificial photosynthesis for harvesting sustainably solar energy. The design of the donor-acceptor systems mimic a part of green plants and bacterial photosynthetic processes. The photochemical events in natural photosynthesis involve the capturing and funneling of solar energy by a group of well-organized chromophores referred to as an ‘anten… more
Date: August 2018
Creator: Obondi, Christopher O
Item Type: Refine your search to only Thesis or Dissertation
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High Temperature Enthalpies of the Lead Halides: Enthalpies and Entropies of Fusion

Description: The objectives of this investigation were: 1. To establish calorimetrically the transition temperature for the orthorhombic to cubic transition exhibited by PbF₂ and to determine the enthalpy of this transition. 2. To determine if the solid-solid phase transitions claimed in the literature for PbCl₂, PbF₂, PbBr₂, and PbI₂ were of thermodynamic importance, and if so, to determine the enthalpies of transition. 3. To determine if the discontinuous thermal expansions reported by Hsu for the lead ha… more
Date: June 1970
Creator: Linsey, Clarence W.
Item Type: Refine your search to only Thesis or Dissertation
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Homework versus daily quizzes: The effects on academic performance within high school pre-AP chemistry.

Description: 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: Refine your search to only Thesis or Dissertation

Homoleptic and Heteroleptic Platinum(II) Complexes for Organic Light Emitting Diodes and Humidity Sensors: Synthesis, Characterization, and Applications

Description: This dissertation focuses on the design, synthesis, characterization of platinum (II) pyridylazolate complexes and develop high performance organic light emitting diodes (OLEDs) and design and execute high-sensitivity humidity sensors based on the luminescent metal-organic complexes of platinum. A majority of existing platinum compounds do not dissolve in organic solvents, making it difficult to analyze the photophysical characteristics of complexes in solution, a key part of understanding chem… more
This item is restricted from view until January 1, 2029.
Date: December 2023
Creator: Farvid, Seyedmajid
Item Type: Refine your search to only Thesis or Dissertation
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Hydantoin Derivatives as Anticonvulsants. I. 5-Cyclohexylalkyl-5-(2-Thienyl)Hydantoins

Description: The study herein described represents a continuation of the work on 5-(2-thienyl)-5-substituted hydantoins which has been in progress in the laboratories of the North Texas State College for the past several years. It has for its purpose the study of the effect of lengthening the carbon chain connecting a cyclohexyl radical to 5-(2-thienyl)hydantoin in the 5- position.
Date: 1949
Creator: Baker, Andy Albert
Item Type: Refine your search to only Thesis or Dissertation
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Hydantoins as Anticonvulsants. III. 5-Alkoxy- and Aryloxymethyl-5-(2-Thienyl) Hydantoins

Description: It has been shown in the case of a compound synthesized in this laboratory that substitution of the thienyl group for one of the phenyl groups in diphenyl hydantoin produces a compound with less toxicity and somewhat greater activity. It was considered of interest to carry out an analogous substitution in the series of 5-phenyl-5-alkoxymethylhydantions.
Date: 1950
Creator: Sadler, Jack W.
Item Type: Refine your search to only Thesis or Dissertation
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Hydantoins as Anticonvulsants. VI. 5-Substituted-Alkoxy Derivatives of 5-Phenylhydantoin

Description: No derivatives of 5-phenylhydantoin with an oxygen atom attached directly in the five position of the hydantoin nucleus have been found in the literature. It was therefore considered of interest to synthesize a series of compounds of this type to determine the effect of the change of the position of the oxygen atom on anticonvulsant activity.
Date: January 1954
Creator: Hoffman, James Rucker
Item Type: Refine your search to only Thesis or Dissertation
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Hydantoins as Anticonvulsants. VIII. 5-Alkylmercapto Derivatives of 3-Methyl-5-Phenylhydantoin

Description: Recent years have seen a rapid increase in the search for new compounds to be employed in the treatment of convulsions associated with epilepsy and related ailments. The properties desired are a higher degree of effectiveness and lower toxicity than those already in use. This thesis describes the effect of methylation of the 5-alkylmercapto-5-phenylhydantoins.
Date: January 1954
Creator: Dick, Clarence Reinhardt
Item Type: Refine your search to only Thesis or Dissertation
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Hydraulic Activity in Synthetic and Commercial Slags

Description: Slag, by itself, shows very little hydraulic activity. However, hydration is greatly accelerated by incorporation of the slag with Portland cement. This phenomenon is due to the activating role of calcium hydroxide released from the hydration of Portland cement. This study was aimed at finding other activators that will increase hydration in both synthetic and commercial slags. The effects of chemical composition and the aggregation state of the slag on the hydration process were also investiga… more
Date: May 1982
Creator: Saad, Bahruddin bin
Item Type: Refine your search to only Thesis or Dissertation
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Hydrogen terminated silicon surfaces: Development of sensors to detect metallic contaminants and stability studies under different environments

Description: Hydrogen terminated silicon surfaces have been utilized to develop sensors for semiconductor and environmental applications. The interaction of these surfaces with different environments has also been studied in detail. The sensor assembly relevant to the semiconductor industry utilizes a silicon-based sensor to detect trace levels of metallic contaminants in hydrofluoric acid. The sensor performance with respect to two non-contaminating reference electrode systems was evaluated. In the fi… more
Date: August 2002
Creator: Ponnuswamy, Thomas Anand
Item Type: Refine your search to only Thesis or Dissertation
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The Hydrolysis of α-(Benzenesulfonyl)-Acetophenone

Description: In view of the unexpected behavior of α-(benzenesulfonyl)-acetophenone toward hydrolysis and because of the possible physiological importance of its derivatives it was deemed of interest to make a further study of the hydrolysis of this compound. It was decided to study both the acid and basic hydrolysis of this compound. The problem consisted of finding a satisfactory means of analyzing the hydrolysis products, and carrying out the hydrolysis under the different conditions.
Date: 1950
Creator: Looney, Jesse M.
Item Type: Refine your search to only Thesis or Dissertation
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Hyperconjugative Interactions in Silylanilines

Description: The purpose of the present work is to study the bonding interactions between the substituents and the ring π system for a series of ortho and para MeₙH₃₋ₙM (M = C or Si, n = 0-3) substituted N,N-dimethylaniline . Both ground and excited-state interactions were studied and their magnitudes determined. The experimental data were then used in conjunction with molecular orbital calculations to differentiate among inductive, hyperconjugative, and d-pπ interactions on the ground and excited states. O… more
Date: May 1975
Creator: Jung, Il Nam
Item Type: Refine your search to only Thesis or Dissertation
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The Impact of Computational Methods on Transition Metal-containing Species

Description: Quantum chemistry methodologies can be used to address a wide variety of chemical problems. Key to the success of quantum chemistry methodologies, however, is the selection of suitable methodologies for specific problems of interest, which often requires significant assessment. To gauge a number of methodologies, the utility of density functionals (BLYP, B97D, TPSS, M06L, PBE0, B3LYP, M06, and TPSSh) in predicting reaction energetics was examined for model studies of C-O bond activation of met… more
Date: December 2015
Creator: Wang, Jiaqi
Item Type: Refine your search to only Thesis or Dissertation
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Impact of Texas High School Science Teacher Credentials on Student Performance in High School Science

Description: 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: Refine your search to only Thesis or Dissertation
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Improvement of Homogeneity and Adhesion of Diamond-Like Carbon Films on Copper Substrates

Description: Electrodeposition method is used to deposit diamond-like carbon (DLC) films on copper substrates via anodic oxidation at low temperature. These films are characterized using Raman spectroscopy, Fourier transform infrared spectroscopy and scanning electron microscopy. Homogeneity of these films is studied using Raman spectroscopy and scanning electron microscopy. Scotch tape peel tests indicate adherent film on copper substrate. Carbon phase transformation is studied using thermal annealing expe… more
Date: August 2004
Creator: Vavilala, Suma
Item Type: Refine your search to only Thesis or Dissertation

In vitro Biomedical Application and Photothermal Therapy Evaluation of Gold Complexes and Gold Nanoparticles

Description: Plasmonic photothermal therapy (PPTT) has a rising promise for treating different cancer cells such as lymphoma or stomach cancer. Technique development of PPTT using metallic nanoparticles is developed upon a modification of the irradiation therapy using two major changes: using a less harmful visible amber light (excluding blue light) and using gold-loaded biocompatible nanoparticles. Acrylate nanoparticles were loaded with desired types of gold nanoparticles at different sizes. The gold-load… more
This item is restricted from view until June 1, 2024.
Date: May 2022
Creator: Shennara, Khaled A
Item Type: Refine your search to only Thesis or Dissertation
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