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1-(4, 4'-Dinitrodiphenylmethyl)-Piperidines; 1-(4-Nitrobenzyl)-and 1-(4-Nitrobenzoyl)-Piperdines: This study experiments with the methods of 1-(4, 4'-Dinitrodiphenylmethyl)-Piperidines; 1-(4-Nitrobenzyl)-and 1-(4-Nitrobenzoyl)-Piperdines.
Ab Initio and Density Functional Investigation of the Conformer Manifold of Melatonin and a Proposal for a Simple Dft-based Diagnostic for Nondynamical Correlation: In this work we address two problems in computational chemistry relevant to biomolecular modeling. In the first project, we consider the conformer space of melatonin as a a representative example of “real-life” flexible biomolecules. Geometries for all 52 unique conformers are optimized using spin-component scaled MP2, and then relative energies are obtained at the CCSD (T) level near the complete basis set limit. These are then used to validate a variety of DFT methods with and without empirical dispersion corrections, as well as some lower-level ab initio methods. Basis set convergence is found to be relatively slow due to internal C-H…O and C-H…N contacts. Absent dispersion corrections, many DFT functionals will transpose the two lowest conformers. Dispersion corrections resolve the problem for most functionals. Double hybrids yield particularly good performance, as does MP2.5. In the second project, we propose a simple DFT-based diagnostic for nondynamical correlation effects. Aλ= (1-TAE [ΧλC]/TAE[XC])/λ where TAE is the total atomization energy, XC the “pure” DFT exchange-correlation functional, and ΧλC the corresponding hybrid with 100λ% HF-type exchange. The diagnostic is a good predictor for sensitivity of energetics to the level of theory, unlike most of the wavefunction-based diagnostics. For GGA functionals, Aλ values approaching unity indicate severe non-dynamical correlation. The diagnostic is only weakly sensitive to the basis set (beyond polarized double zeta) and can be applied to problems beyond practical reach of wavefunction ab-initio methods required for other diagnostics.
Acetophenone Derivatives; N-Diphenylmethyl and N-Fluorenyl Piperidines: This thesis is a study of α-(4-aminophenylsulfonyl)-acetophenone derivatives; n-diphenylmethyl and n-fluorenyl piperidines.
Addition Reactions of Some Aromatic Aldazines: The paper explores the conclusion that the addition compound was bicyclic, and that the addition of each of the two moles of cyanic acid was dependent upon the other.
The Adsorption of Radioactive Isotopes on Precipitates: This thesis concerns the investigation of radioisotopes as indicators for precipitation reactions. As a precipitate forms in the presence of a radioisotope, adsorption may take place on its surface. If this adsorption changes markedly at the stoichiometric point it will be possible to use this variation as an indicator for the reaction.
The Adsorption of Radioactive Isotopes on Specific Precipitates: The purpose of this investigation is to reveal the effects of certain factors affecting adsorption on some specific precipitates. It is hoped that the choice of precipitate types will enable extension of the information gained here to other precipitates similar to those investigated.
Amine Derivatives of 3-chloro-5(8?)-nitro-1,4-naphthoquinone: This work deals with the preparation of amine derivatives of 3-chloro-5(8?)-nitro-1,4-naphthoquinone which are to be tested for anti-tubercular activity by Parke, Davis and Company.
Amino Acid Complexes of Rhodium(III): This thesis will explore and study rhodium, a group VIII element that has rarely been studied.
a-Amino Alcohol Derivatives of Methyl P-Nitrophenyl Acetate: This thesis describes the synthesis of a series of dialkylaminoalkoxy derivatives of methyl p-nitrophenylacetate for testing as anti-histamine or hay fever drugs.
An Analysis of Elementary Science Material Included in Certain Courses of Study and Text Books: The purpose of this study is to assess the contribution of elementary science to the curriculum. The finding of the investigation summarized in table form.
The Analysis of Fire Debris Using Nuclear Magnetic Resonance Spectroscopy: This paper describes a new technique for analyzing fire debris using nuclear magnetic resonance (NMR) spectroscopy. Petroleum distillates, which are commonly used accelerants, were weathered, burned, and steamdistilled. These, as well as virgin samples of the accelerants, were analyzed by gas chromatography and nuclear magnetic resonance spectroscopy. In addition, solvent studies and detectibility limit studies were conducted. The use of NMR is described as a valuable adjunct to the existing methods of analysis.
An Analysis of the Effectiveness of Computer Assisted Instruction in General Chemistry at an Urban University.: The science-major General Chemistry sequence offered at the University of Houston has been investigated with respect to the effectiveness of recent incorporation of various levels of computer technology. As part of this investigation, questionnaire responses, student evaluations and grade averages and distributions from up to the last ten years have been analyzed and compared. Increased use of web-based material is both popular and effective, particularly with respect to providing extra information and supplemental questions. Instructor contact via e-mail is also well-received. Both uses of technology should be encouraged. In contrast, electronic classroom presentation is less popular. While initial use may lead to improved grades and retention, these levels decrease quickly, possibly due to a reduction in instructor spontaneity.
An Analysis of the Naphtha Cut of Cooke county, Texas, Crude Oil: This study attempted to determine hydrocarbons in the crude oil by comparing the results obtained using the two methods of analysis: chemical analysis and Kurtz-Headington analysis. The Kurtz-Headington analysis was found to be adequate to determine hydrocarbons in the crude oil.
Analysis of Trace Amounts of Adulterants Found in Powders/Supplements Utilizing Direct Inject, Nanomanipulation, and Mass Spectrometry: The regulations of many food products in the United States have been made and followed very well but unfortunately some products are not put under such rigorous standards as others. This leads to products being sold, that are thought to be healthy, but in reality contain unknown ingredients that may be hazardous to the consumers. With the use of several instrumentations and techniques the detection, characterization and identification of these unknown contaminates can be determined. Both the AZ-100 and the TE2000 inverted microscope were used for visual characterizations, image collection and to help guide the extraction. Direct analyte-probed nanoextraction (DAPNe) technique and nanospray ionization mass spectrometry (NSI-MS) was the technique used for examination and identification of all adulterants. A Raman imaging technique was than introduced and has proven to be a rapid, non-destructive and distinctive way to localize a specific adulterant. By compiling these techniques then applying them to the FDA supplied test samples three major adulterants were detected and identified.
Anion Exchange and Competition in Layered Double Hydroxides: Exchange reactions of anions, especially ferrocyanide and carbonate, with layered double hydroxides (LDHs) were investigated in relation to the origin of life on the early Earth. The effect on ferrocyanide exchange of concentration, pH, reaction time and cations are discussed. It was found that there were two different kinds of ferrocyanide species: one was that intercalated into the layered structure, occupying a site of D symmetry within the LDHs, while in the other, the ferrocyanide group retains full O symmetry. In addition, very low concentration, ferrocyanide associated with LDH will change its FTIR absorption shape. Carbonate was much more strongly intercalated than ferrocyanide into the LDHs, probably because of the strong hydrogen bonding.
ANTI Preference of the Pyramidalized Radical Center to the Two Fluorines in Difluoro Cyclic Compounds.: An extensive study of disubstituted cycloalkanes like CnH2n where n=3,4,5 and 6 using DFT((U)B3LYP/6-31G(d) and 6-311+G(2df,2p)) calculations is presented focusing on the effect of pyramidalization of the radical center. A potential energy surface (PES) analysis shows that the radical prefers to pyramidalize anti to the two cis fluorines in the disubstituted cycloalkanes. The degree of pyramidalization for 1,2-difluorocyclopropyl radical is 43.9o away from the cis fluorines whereas for 1,3-difluorocyclobutyl radical, 1,3-difluorocyclopentyl radical and 1,3-difluorocyclohexyl radical is 3.8o, 5.4o and 14.5o respectively away from the cis fluorines. The importance of this pyramidality effect in these compounds is discussed in context with the carbon-hydrogen bond dissociation energies (BDE's) because the preference of the radical centers to pyramidalize anti to the fluorines affects the bond dissociation energy. Importance of steric effect and unfavorable electronic interactions have been extensively explored in planar permethylated cyclobutadiene (Me4CBD) and cyclooctatetraene (Me8COT) using ((U)B3LYP/6-31G(d) and 6-311+G(2df,2p)) calculations. It is thought that steric interactions dominate electronic interactions in Me8COT, while this works opposite in case of Me4CBT. Instead, in Me4CBD the number of unfavorable electronic interactions between π bonds and out-of-plane hydrogens plays the dominant role in determining the relative energies. Interactions between the π bonds of CBD and the out-of-plane hydrogens on carbons attached to the four-membered ring becomes very interesting when the ring size changes. With ethano bridge on the cyclobutadiene ring interaction with the diagonal bonds results in non-bonding AOs across the other diagonal having the opposite phase in the highest occupied (HO)MO. If the HOMO and LUMO are switched, bis-ethano-bridged tetrahedrane is formed. It is suggested that bis-ethano-bridged tetrahedrane is thermodynamically more stable than bis-ethano-bridged cyclobutadienes. While the reverse is true for unsubstituted cyclobutadienes. The ability of ethano bridges to reverse the usual order is because it causes the doubly-bonded carbons to pyramidalize.
Application of Concentration, Adsorption and pH in the Precipitation of the Metal Ions of Groups II and III: In this thesis, the process involved in the precipitations and separations of the metal of Group II and Group III studied. Suggestions have also been offered whereby students can make an analysis without loosing metals in the initial precepitation.
An Application of the Reformatsky Reaction to the Thiophene Series of Compounds: In view of the increasing importance of thiophene derivatives as chemotherapeutic agents, it was considered of interest to apply the Reformatsky reaction to the synthesis of compounds containing the thiophene nucleus with the thought that these might serve as intermediates for further syntheses.
Application of UV-Vis Spectroscopy to the Monitoring, Characterization and Analysis of Chemical Equilibria of Copper Etching Baths: The continuously increasing demand for innovation in the miniaturization of microelectronics has driven the need for ever more precise fabrication strategies for device packaging, especially for printed circuit boards (PCBs). Subtractive copper etching is a fundamental step in the fabrication process, requiring very precise control of etch rate and etch factor. Changes in the etching chemical equilibrium have significant effects on etching behavior, and CuCl2 / HCl etching baths are typically monitored with several parameters including oxidation-reduction potential, conductivity, and specific gravity. However, the etch rate and etch factor can be difficult to control even under strict engineering controls of those monitoring parameters. The mechanism of acidic cupric chloride etching, regeneration and recovery is complex, and the current monitoring strategies can have difficulty controlling the interlocking chemical equilibria. A complimentary tool, thin-film UV-Vis spectroscopy, can be utilized to improve the current monitoring strategies, as UV-Vis is capable of identifying and predicting etching behavior that the current standard methodologies have difficulty predicting. Furthermore, as a chemically-sensitive probe, UV-Vis can investigate the complex changes to the chemical equilibrium and speciation of the etch bath, and can contribute overall to significant improvements in the control of the copper etching system in order to meet the demands of next-level design strategies.
Applications of Nanomanipulation Coupled to Nanospray Mass Spectrometry in Trace Fiber Analysis and Cellular Lipid Analysis.: The novel instrumentation of nanomanipulation coupled to nanospray mass spectrometry and its applications are presented. The nanomanipulator has the resolution of 10nm step sizes allowing for specific fine movement used to probe and characterize objects of interest. Nanospray mass spectrometry only needs a minimum sample volume of 300nl and a minimum sample size of 300attograms to analyze an analyte making it the ideal instrument to couple to nanomanipulation. The nanomanipulator is mounted to an inverted microscope and consists of 4 nano-positioners; these nano-positioners hold end-effectors and other tools used for manipulation. This original coupling has been used to enhance the current abilities of cellular probing and trace fiber analysis. Experiments have been performed to demonstrate the functionality of this instrument and its capabilities. Histidine and caffeine have been sampled directly from single fibers and analyzed. Lipid bodies from cotton seeds have been sampled indirectly and analyzed. The few applications demonstrated are only the beginning of nanomanipulation coupled to nanospray mass spectrometry and the possible applications are numerous especially with the ability to design and fabricate new end-effectors with unique abilities. Future study will be done to further the applications in direct cellular probing including toxicology studies and organelle analysis of single cells. Further studies will be directed in forensic applications of this instrument including gunshot residue sampled from fibers.
Applications of Single Reference Methods to Multi-Reference Problems: Density functional theory is an efficient and useful method of solving single-reference computational chemistry problems, however it struggles with multi-reference systems. Modifications have been developed in order to improve the capabilities of density functional theory. In this work, density functional theory has been successfully applied to solve multi-reference systems with large amounts of non-dynamical correlation by use of modifications. It has also been successfully applied for geometry optimizations for lanthanide trifluorides.
An Approach Towards the Total Synthesis of Clonostachydiol: The syntheses of the unsymmetrical 14-membered bismacrolides have been reviewed. A total synthesis of clonostachydiol, the latest to join this family, has been attempted using trimethylsilyl acetylene as the builiding block and palladium catalyzed reactions for the formation of key bonds. The alkyne groups were introduced by Stille coupling of trimethylstannylethynyltrimethylsilane with an acid chloride for one fragment and by addition of lithiotrimethylsilyl acetylene to an aldehyde for the other. Lactic acid derivatives were chosen as starting materials for both fragments, thus introducing two of the chiral centers. The remaining stereocenters were introduced using stereoselective reductions of ketones.
Aqueous Solubilities and Transformation of Chlorinated Benzenes: Aqueous solubilities of twelve chlorinated benzenes were determined by two methods. In one method, the solutions in water were prepared by a vigorous stirring method followed by n-hexane extraction and GC-ECD analysis. In the second method, HPLC was used to prepare the saturated solutions. Experimental results were compared with the predictive values, the relative standard deviations are around 10%. Most of the chlorinated benzenes exhibit water induced transformations. The transformation products were either isomeric or with higher and lower numbers of chlorine substituents. The transformation phenomena can be explained by polarity, symmetry, reactivity of the chlorine atoms, and hydrophobic interactions. The mechanism of the transformation is governed by the radical mechanism.
The Ascorbic Acid Metabolism of Fifty College Women in the North Texas State Teachers College: A study of the ascorbic acid metabolism of a group of fifty college women in the North Texas State Teachers College between the months of April and July, 1943.
Attempted Synthesis of 5-Allyl-5-(2-Thienyl)-Barbituric Acid: This thesis describes attempts to synthesize 5-allyl-5-(2-thienyl)-barbituric acid as an improved anticonvulsant.
Attempted Synthesis of Dibarbituric Acid: This study is an attempted synthesis of dithienyl barbituric acid.
The Attempted Synthesis of some Heterocyclic Sulfones: This thesis describes two experiments: one related to antihistamines, and the other related to antitubercular compounds.
Baeyer-Villiger Oxidation of 1,7- & 1,9-dibromopentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione: Baeyer-Villiger oxidation of 1,9-dibromopentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione (1,9-dibromo-PCU-8,11-dione) was performed by using an excess amount of m-chloroperbenzoic acid (3 equivalents) and resulted in the formation of the corresponding monolactone. The reaction would not proceed to the dilactone stage. The structure of the reaction product was established unequivocally via single crystal X-ray diffraction. Baeyer-Villiger oxidation of 1,9-dibromo-PCU-8,11-dione using ceric ammonium nitrate (CAN) was also performed and afforded a mixture of lactones. Only one of these lactones, which also contained an alkene functionality, could be isolated and characterized. 1,7-dibromo-PCU-8,11-dione was also reacted with CAN, yielding the mono-lactone, which has also been characterized.
Barbituric Acids as Anticonvulsants. IV. 5-Substituted-Mercapto Derivatives of 5-Phenylbarbituric Acids.: This study involves compounds of the barbituric acid series are well known for their use as anesthetics and sedatives.
Barbituric Acids. VI. 5-substituted-mercapto Derivatives of 5-ethylbarbituric Acid: The reaction of 5-bromo-5-ethylbarbituric acid with mercaptan and pyridine in cold ether solution was studied and was found to be satisfactory for the preparation of the compounds reported in this work.
Barbituric Acids. VII. 5-alkyl-derivatives of 5-ethoxy-barbituric Acid: A great deal of research has been devoted in recent years to the search for new drugs for the treatment of epilepsy and related convulsive disorders. This emphasis is occasioned by the fact that no one drug is effective for all patients, and also by the fact that the toxicity of a drug varies considerably from one patient to another. Among the most effective drugs are certain members of the hydantoin and barbituric acid series. For some time there has been in progress in this laboratory an investigation of members of these two series in which a hetro atom attached directly to the hetrocyclic nucleus is introduced into the side chain at position five of these two series.
Barbituric Acids. VIII. 5-substituted-5-(1-pyrrolidyl)barbituric Acids: The purpose of this investigation then was the preparation of a series of 5-substituted-5-(1-pyrrolidyl)barbituric acids in which R would consist of alkyl groups ranging in size from methyl to amyl, and other groups such as phenyl and benzyl. These compounds are to be tested elsewhere for hypnotic and anticonvulsant activity.
Barbituric Acids. V. 5-substituted-mercapto Derivatives of 5-isoamylbarbituric Acid: Since no mention has been found in the literature of any 5-substituted mercapto-5-alkyl derivatives of barbituric acid, it was thought to be of interest to prepare a series of compounds containing sulfur attached directly to the barbituric acid nucleus. 5-substituted mercapto-5-isoamylbarbituric acids were chosen as representative of barbituric acids in which the alkyl group has a fairly high molecular weight.
Base Effects on the Thermal Decomposition of Sec-butyllithium Solutions: The pyrolysis of sec-butyllithium in solution was studied in an attempt to understand the loss of stereo-specificity and the atypical kinetics that have been reported. Additionally, the effect of added lithium alkoxides was studied to determine their effects on the highly reactive sec-butyllithium substrate.
Bis Ammonium Salts of Dialkylaminoalkoxypropionitriles: This paper concerns the preparation of some bis derivatives of dialkylaminoalkoxypropionitirles from trimethylene, hexamethylene, octomethylene, and decamethylene bromides. These compounds are to be tested for curariform activity and anesthetic values by Parke, Davis and Company.
Bonding Studies on Organolithium Compounds: This study is concerned with the nature of the relatively unusual bonding which occurs in organolithium compounds as a direct result of the oligomerization and possible explanations for that bonding.
Boron Nitride by Atomic Layer Deposition: A Template for Graphene Growth: The growth of single and multilayer BN films on several substrates was investigated. A typical atomic layer deposition (ALD) process was demonstrated on Si(111) substrate with a growth rate of 1.1 Å/cycle which showed good agreement with the literature value and a near stoichiometric B/N ratio. Boron nitride films were also deposited by ALD on Cu poly crystal and Cu(111) single crystal substrates for the first time, and a growth rate of ~1ML/ALD cycle was obtained with a B/N ratio of ~2. The realization of a h-BN/Cu heterojunction was the first step towards a graphene/h-BN/Cu structure which has potential application in gateable interconnects.
Brainstem Lipids' Relationship to Death: Previous work relating postmortem findings with cause of death have focused on the vitreous portion of the body. This research investigated the link between phospholipids in the brainstem and cause of death. The lipids were extracted by the Folch extraction method and then separated by High Performance Thin Layer Chromatography. These techniques gave excellent separation and resolution. Results showed no link between cause of death and the type of lipids found in the brainstem after death.
A Carbon-13 and Lithium-6 NMR Study of Alkyllithium Compounds: A variable temperature 13C and 6Li NMR study has been conducted for 6Li-enriched ethyl-, n-propyl-, isopropyl-, n-butyl-, isobutyl-, t-butyl--, isopentyl-, 2-ethylbutyl-, and n-hexyllithium in cyclopentane. Significant differences in the 13C NMR parameters are observed as a function of the alkyl group and temperature. These changes are compared to the 6Li spectra and explained in terms of the aggregates present. 13C-6Li coupling is readily observed in both the 13 6 C and Li spectra of compounds which contain branching at either the alpha or beta carbons of the alkyl group. This coupling has been used to identify the aggregates present in solution and to identify the fluxional behavior of these aggregates.
Carbon-13-carbon-13 Coupling Constants in Fluorene and O-Methylbenzene Derivatives: A model system to calculate single-path coupling constant was devised to see if the couplings are additive in a system which has a dual-pathway. The system chosen was o-methyl-13C-benzoic acid. Because of anomalies in the data, the series was extended. Hybridization of the label appeared to have relatively little effect, and the conformation of the substituents very important.
Characterization of Aprotic Solutes and Solvents Using Abraham Model Correlations: Experimental data were obtained for the computation of mole fraction solubilities of three dichloronitrobenzenes in organic solvents at 25oC, and solubility ratios were obtained from this data. Abraham model equations were developed for solutes in tributyl phosphate that describe experimental values to within 0.15 log units, and correlations were made to describe solute partitioning in systems that contain either "wet" or "dry" tributyl phosphate. Abraham model correlations have also been developed for solute transfer into anhydrous diisopropyl ether, and these correlations fit in well with those for other ethers. Abraham correlations for the solvation of enthalpy have been derived from experimental and literature data for mesitylene, p-xylene, chlorobenzene, and 1,2-dichlorobenzene at 298.15 K. In addition, the enthalpy contribution of hydrogen bonding between these solutes and acidic solvents were predicted by these correlations and were in agreement with an established method. Residual plots corresponding to Abraham models developed in all of these studies were analyzed for trends in error between experimental and calculated values.
Characterization of Ionic Liquid As a Charge Carrier for the Detection of Neutral Organometallic Complexes Using Electrospray Ionization Mass Spectrometry: A novel application of ionic liquid as a charge carrier for the analysis and detection of neutral organometallic complexes using a mass spectrometer has been presented. The mass spectrometer detects only charged compounds which raise a difficulty in analyzing a neutral molecule that lacks a basic site to associate with charge. Therefore, an effective way of providing charge has always been an area of keen interest in the field of mass spectrometry. Ionic liquids have a very fascinating property of forming a cation-? interaction with other molecules to give a charged complex. In order to take advantage of this, it is important to know the geometric structure of the complex. Advanced methodologies like hydrogen-deuterium exchange and computational calculations have been used assisting in better understanding of the structure of the ionic liquid complexes.
A Chemical Analysis of Soft Wheat: The purpose of this piece of research is to determine the chemical composition of soft winter wheat, and to make a comparative study of it. A study is also made concerning its possibilities as a balanced food.
A Chemical Analysis of the Blackeyed Pea: The purpose of this research problem is to determine the chemical composition of the blackeyed pea and to make a comparative study of the results. The value of the blackeyed pea as food, its chemical nature, and possible industrial uses are studied and recorded.
Chemical Analysis of the Bottom Deposits of Artificial Lakes with Special Emphasis on Lake Dallas: This study is for the purpose of determining the chemical content of typical artificial reservoir bottom deposits.
A Chemical Analysis of the Important Soils of Dimmit County, Texas: The purpose of this study is to collect sample soils from uncontaminated horizon (by digging completely through the soil profile or strata) and provide a chemical analysis of the important soils of Dimmit county, Texas.
The Chemical Analysis of the Mebane Cottonseed Kernel: The purpose of this work is to make a fairly complete chemical analysis of the Mebane 804-50 cottonseed kernel. A brief history of cotton plant and the economic value of its products are also presented.
A Chemical Analysis of the Peanut: The object of this paper is to make an analysis of the mineral and food content of the peanut and to compare them with a balanced food.
A Chemical Analysis of the Soils of Denton County, Texas: The purpose of this study was to analyze the different soils in Denton, Texas. For the purpose of this study, the soils of Denton County are divided into three general groups with respect to origin: 1)those formed in place by the weathering of consolidated rocks, 2) those formed from the weathering of unconsolidated rocks, and 3) alluvial soils. A chemical analysis of representative samples of Bell Clay, Kirvin fine sandy loam, and San Saba clay has been made, and shown to have a strict correlation with their respective geological origins.
The Chemical Analysis of the Tennessee Green Pod Pole Bean: The object of this paper is to compare the Tennessee green pod pole bean with other beans as to chemical composition and food value.

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