Physical Sciences and Mathematics Commons^™

Gc/Ms And Lc/Ms Approaches To Chemical Communication In Plants And Marine Cyanobacteria, Carolyn Keim

University of the Pacific Theses and Dissertations

Natural products are small organic compounds synthesized by living organisms including plants, animals, and microbes. These fall into one of two categories, primary metabolites are required for survival, but secondary metabolites usually play a more accessory role. Extracts from organisms have proven to be useful to humans throughout history. Prior to evidence-based western medicine practices, natural products were the only source of medicine and remain as a treatment source for underdeveloped nations. Today, natural products have either been approved by or have served as the template for many FDA approved drugs. Based on a survey of all FDA approved drugs …

The Vagabond Flourine Atom Revisited: Dissociative Photoionization Of Tri- And Pentafluoropropene, Jessica K. De La Cruz

University of the Pacific Theses and Dissertations

Photoelectron Photoion Coincidence (PEPICO) Spectroscopy studies on two unsaturated hydrofluorocarbons (HFCs), also known as hydrofluoroolefines (HFOs), are presented here. Previously, the Sztáray group has studied the dissociation of trans-1,3,3,3-tetrafluoroprop-1-ene (ElixClean), which is a fourth-generation refrigerant and propellant and has lower global warming potential than its precursors. My study is an extension of the ElixClean study as it aims to explore how the different number of fluorine atoms impact the dissociation reactions of these molecules. Both 3,3,3-trifluoropropene (TFP) and cis-1,2,3,3,3- pentafluoropropene (PFP) are also utilized as propellants and refrigerants.Measurements were carried out with remote access to the CRF-PEPICO (combustion reactions followed …

Gas-Phase Acid-Base Properties And Conformations Of Oligopeptides Through Mass Spectrometry And Computational Studies, Yuntao Zhang

University of the Pacific Theses and Dissertations

This dissertation presents a comprehensive study of the peptides of interest to deeper understand the gas-phase acid-base properties in relation to their conformations and chirality. In the first part of the study, two pairs of alanine (A)-based isomeric peptides consisting of a basic probe, lysine (Lys) or 2,3-diaminopropionic acid (Dap), were investigated to understand the nature of the enhanced basicity when the basic probe was moved from the N-terminus to the C-terminus. In the second part of the study, alanine-based peptides containing a cysteine (C) as the acidic probe were investigated to understand the chirality effects on the gas-phase acidity …

Synthesis And Conformational Study Of Triazolylcyclohexanols And Trans-2-(Azaarylsulfanyl)-Cyclohexanols, Mulinde R. Ruyonga

University of the Pacific Theses and Dissertations

Amino-cyclohexanol derivatives have been successful models for pH-triggered conformational switches. By changing the groups on the amine nitrogen, these models provide a wide pH-range in which a switch can occur. The pH-induced switch of conformation can be monitored by 1H NMR.In this work, structurally similar trans-2-(azaarylsulfanyl)-cyclohexanol derivatives (Scheme 1) and trans-2-triazolylcyclohexanol derivatives (Scheme 2) have been explored for the first time as compounds with a potential for the analogous pH-induced conformational switch. The azaarylsulfanyl groups showed selective conformational flexibility while the triazolyl group showed a strong preference for the equatorial position. Further, conformational studies were done on a series of …

Elephant And Anchors ‒ Photoelectron Photoion Coincidence Spectroscopy Of Small Oxygenated Molecules, Apeter Weidner

University of the Pacific Theses and Dissertations

The dissociative photoionization reactions of two small, oxygenated organics, namely 1,3-dioxolane and methyl vinyl ketone, were studied by photoelectron photoion coincidence (PEPICO) spectroscopy. Experiments involving 1,3-dioxolane were carried out in the photon energy range of 9.5‒13.5 eV. The statistical thermodynamics model shows that a total of six dissociation channels are involved in the formation of three fragment ions, namely C3H5O2+ (m/z 73), C2H5O+ (m/z 45) and C2H4O+ (m/z 44), with two channels contributing to the formation of each. By comparing the results of ab initio quantum chemical calculations to the experimentally derived appearance energies of the fragment ions, the most …

Approaches To The Search Of Platinum Anticancer Agents: Derivatizing Current Drugs And Incorporating Hdac Inhibition, Chao Feng

University of the Pacific Theses and Dissertations

Platinum-based anticancer drugs, such as cisplatin, carboplatin, and oxaliplatin, have been approved for clinical use worldwide for decades. Despite their enormous success, their widespread application is hindered by either cross-resistance or toxic side effects, including nephrotoxicity and neurotoxicity. The need to overcome these drawbacks has stimulated the search for new platinum-based drugs.

This dissertation will start with the accidental discovery of cisplatin, followed by an introduction of other platinum-based anticancer agents, including the action mechanism, general structures, and development history. Picoplatin is a newer generation of platinum-based anticancer agent. The bulky 2-methylpyridine as a non-leaving group on picoplatin could reduce …

Exploring The Molecular Origin Of Jet Fuel Thermal Oxidative Deposition Through Statistical Analysis Of Mass Spectral Data And Pyrolysis Gas Chromatography/Mass Spectrometry Of Deposits, Krege Matthew Christison

University of the Pacific Theses and Dissertations

ASTM D3241 (Standard Test Method for Thermal Oxidation Stability of Aviation Turbine Fuels) measures the thermal oxidative stability of jet fuels under elevated temperature and pressure conditions. When jet fuels fail ASTM D3241, either at the refinery or in the distribution system, there can be supply disruptions and financial losses. Understanding the causes of poor thermal oxidative stability in jet fuels could help prevent or mitigate issues. In order to develop a deeper understanding of the molecular precursors that lead to ASTM D3241 failures, a number of analytical methodologies and data treatment techniques have been developed, applied, and reported here. …

Roaming Transition States And Highly Accurate Thermochemistry: A Pepico Study Of Two Small Combustion Systems, Kyle John Covert

University of the Pacific Theses and Dissertations

Two small combustion systems, methyl hydroperoxide (CH₃OOH) and 2-propanol ((CH₃)₂CHOH), were studied using imaging photoelectron photoion coincidence spectroscopy (iPEPICO), which combines photoelectron spectroscopy and photoionization mass spectrometry to detect coincident photoelectron-photoion pairs. In the photon energy range of 11.4–14.0 eV, energy selected CH₃OOH⁺ ions dissociate into CH₂OOH⁺, HCO⁺, CH₃⁺, and H₃O⁺ ions. The lowest-energy dissociation channel is the formation of the cation of the smallest “QOOH” radical, CH₂OOH⁺. A statistical rate model fitted to the …

Liposome-Coated Magnesium Phosphate Nanoparticle For Delivery Of Cytochrome C Into Lung Cancer Cells A549, Weizhou Yue

University of the Pacific Theses and Dissertations

Proteins are large biomolecules that have great therapeutic potential in treating many human diseases. However, chemical/enzymatic degradation, denaturation, and poor penetration into cells are some of the challenges for clinical use of intracellular proteins.

Previously, our group has developed cationic lipid-coated magnesium phosphate nanoparticle (LP MgP NP-CAT) formulations to enhance the intracellular delivery of the negatively charged protein catalase. The goal of the current research is to develop a formulation to deliver cytochrome c (CytC), a positively charged protein into lung cancer cells A549. Specifically, this thesis research prepares and tests liposome-coated magnesium phosphate nanoparticle for delivery of cytochrome c …

Synthetic Methods For Ester Bond Formation And Conformational Analysis Of Ester-Containing Carbohydrates, Sven Hackbusch

University of the Pacific Theses and Dissertations

This dissertation encompasses work related to synthetic methods for the formation of ester linkages in organic compounds, as well as the investigation of the conformational influence of the ester functional group on the flexibility of inter-saccharide linkages, specifically, and the solution phase structure of ester-containing carbohydrate derivatives, in general.

Stereoselective reactions are an important part of the field of asymmetric synthesis and an understanding of their underlying mechanistic principles is essential for rational method development. Here, the exploration of a diastereoselective O-acylation reaction on a trans-2-substituted cyclohexanol scaffold is presented, along with possible reasons for the observed reversal of stereoselectivity …

The Effect Of Tungsten(0)Pentacarbonyl On Coordinated Ligands, Janice Imada Byington

University of the Pacific Theses and Dissertations

A series of monosubstituted tungsten(0)pentacarbonyl complexes, W(CO)₅L (L = water, hydrogen sulfide, pyrazine, pyrimidine, 4,4'-bipyridine, 4-cyanopyridine, isonicotinamide, and methanol) were synthesized and characterized. The purpose of this project was to determine the effect of the W(CO)₅ moiety on the coordinated ligand, L.

The visible spectra of the synthesized W(CO)₅L complexes typically exhibited a maximum around 400 nm ((epsilon) (TURN) 4000). The infrared spectra of these complexes exhibited the characteristic three band pattern (2A₁ + E) in the carbonyl region ((TURN)2070 cm^-1, (TURN)1930 cm^-1, (TURN)1900 cm^-1. The pKa's of …

A Matrix Isolation Study Of The Reactions Of Oxygen(Singlet-D) With The Chlorofluoromethanes Fluorotrichloromethane, Dichlorodifluoromethane And Chlorotrifluoromethane, Richard Thomason Burke

University of the Pacific Theses and Dissertations

We have studied the reactions of O(¹D) with CC1₃F, CC1₂F₂ and CC1F₃ in CO₂, SF₆ and N₂O matrices, and in neat mixtures. Photolysis of cryogenic mixtures of ozone and the chlorofluoromethanes in various matrix hosts resulted in production of O(¹D) which migrated through the matrix to react with the Freon molecules. Products were detected by infrared spectroscopy of the matrix deposits, with assignments confirmed by comparison of ¹⁶O and ¹⁸O absorption bands with literature values. Evidence for oxygen atom insertion into a C-C1 …

Isoviscosity Curves In The Analysis Of The Pressure--Temperature Dependence Of Liquid Viscosity., Gayle Nathaniel King

University of the Pacific Theses and Dissertations

The temperature and pressure dependence of liquid viscosity has been extensively discussed in the chemistry, physics, and engineering literature for over half a century. Thus far, theoretical ab initio calculations of temperature and pressure effects on viscosity have been unsuccessful. Therefore there have been numerous attempts to relate fundamental properties of liquid state models with experimental viscosity, temperature, pressure, and density (η,T, P, ρ) data. This work has resulted in many semi-empirical equations expressing η as functions of temperature, pressure, volume, density, chain length, molecular weight, degrees of freedom, etc.

Analysis Of Rocks And Minerals By Attenuated Total Reflection With Atlas, Donald Franklin Anderson

University of the Pacific Theses and Dissertations

Routine non-destructive analyses of rocks and minerals in slab or powder form maybe practicable by the application of the technique of attenuated total reflection [ATR] in infrared [IR] spectrophotometry.

An atlas of spectra would serve the analytical chemist and geologist, who in turn would serve the miner, the lapidarist, and other groups interested in rocks and minerals.

No effort has been made to produce an atlas of spectra of rocks and minerals by ATR. No ATR spectra of rocks and minerals were found in the literature. The history of ATR indicates that it is still in its early stages of …

The Preparation And Characterization Of The Palladium(Ii) And Platinum(Ii) Chelates Of Three Cyclic Tertiary Amino Acids., Floyd Michael Hogue

University of the Pacific Theses and Dissertations

The purpose of this study was to prenare and characterize the palladium (II) and platinum (II) chelates of 1-pyrrolidineacetic acid, 1-piperidineacetic acid, and hexahydro-1-azepineacetic acid.

The ligands were prepared by reacting the cyclic secondary arnines (pyrrolidine, piperidine, and hexahydroazepine) with sodium chloroacetate. The resulting cyclic tertiary amino acids were saponified and, finally, converted to the hydrochloride salts by neutralization with hydrochloric acid.

The chelates were prepared by adding 1.0 millimole of K₂PdC1₄ or K₂PtC1₄ to a solution made by dissolving 2.0 Millimoles of amino acid hydrochloride in 25 ml. of water. The pH was …

The Kinetics And Mechanism Of The Reaction Of Chromium(Ii) With Pentaaquodiiodomethyl Chromium(Iii) And Pentaaquomonoiodomethyl Chromium(Iii) Ions., Ronald Sinclair Nohr

University of the Pacific Theses and Dissertations

Transition metal ions, in low oxidation states, have gained increasing use as versatile reducing agents for a number of organic compounds. The ability of metal ion to act as reducing agents in organic reactions is frequently thought to be due to the formation of intermediates which contain an organic species bound to a metal, although the identy of these organo-metallic intermediates has been determined in relatively few cases.

The purpose of this research was to investigate the kinetics and mechanism of one such reaction: the reduction of iodoform to methane by chromium(II). Two air stable organochromium(III) intermediates were separated and …

Formation And Kinetics Of Dissociation Of Some Pentaaquotrihalomethyl Chromium(Iii) Ions., Sher Khan Malik

University of the Pacific Theses and Dissertations

The present.study was an investigation of the formation and kinetic stability of store complexes contain.ir)ing a chromium-carbon bond in an aqueous medium. An orange-brown pentaaquotrifluoromethylchromium(III) ion was obtained by the reduction of trifluororrethyl iodide with Cr(II) and is the most inert of any organochrotnium(III) complex known. The initial aquation rates of trifluoromethylchromium(III) ion were described by the differential rate law -dln [(H₂O)₅CrCF₃²⁺]/dt = k_{o + k1(H⁺)}

The products of the initial reaction were hexaaquochromium (III), carbon monoxide and HF. The values of k_o and k₁ at …

Dipeptide Complexes Of Palladium(Ii) And Platinum(Ii), Lewis Enos Nance

University of the Pacific Theses and Dissertations

Due to recent interest in the role of heavy metals in enzymes. oxygen-carrying molecules. and anticarcinogenic compounds, the study of metal-protein bonding has assumed a new importance. Studies have been made utilizing platinum compounds as anticarcinogenic agents in several different types of cancerous activity. No study of the mechanism by which Pd(II) and Pt(II) compounds exhibit anticarcinogenic properties has been made to date.

The purpose of this research was to investigate the nature of bonding of Pd(II) and Pt(II) with various dipeptides, which were chosen in this study as a basic unit of protein-like material. These compounds have the advantage …

Palladium(Ii) And Platinum(Ii) Complexes Of 2-Cyanophenyl Diphenylphosphine, David Harrison Payne

University of the Pacific Theses and Dissertations

There has been no successful chelation of any phosphorus-acetylenic or phosphorous-nitrile ligand. The objectives of this study were to synthesize such ligands and to study their chemistry and chelating tendencies. The best choice appeared to be the preparation of ortho-substituted triphenylphosphines similar to the chelating ligand allylphenyldiphenylphosphine. The Grignard reactions utilized in the preparation of the olefinic compound could not be used in most cases due to the high reactivity of the acetylene and nitrile function Bromobenzene and iodobenzene have been reacted with alkali metal phosphines under conditions that were probably too drastic for the acetylenic and nitrile functions. There …

Fluorescence Lifetimes And Quantum Efficiencies Of Some 1,10-Phenanthrolines, Paul John Tabakian

University of the Pacific Theses and Dissertations

Fluorescence properties of fourteen substituted 1,10-Phenanthrolines were determined using two different solvent systems. Hour different sets of experiments were performed in order to measure fluorescence lifetimes, quantum efficiencies, absorption and corrected fluorescence spectra, oscillator strengths, and Stoke’s shifts. Two of the phenanthrolines, the 5-Nitro-1,10-Phenanthroline and the 1,10-Phenanthroline-5,6-Dione, did not fluoresce.

A new equation was developed in order to extract the true fluorescence lifetimes τ from the observed fluorescence output f(t), and the lamp decay function I(t). This equation was [see PDF] where “A” was the weight factor or the normalization constant for the appropriate functions. A test of this equation …

The Preparation And Determination Of Some Of The Properties Of The Dicarboxylic Amino Acid Chelates Of Platinum(Ii) And Palladium(Ii), Gordon Harold Williams

University of the Pacific Theses and Dissertations

It is surprising that no one has considered that coordination might have some effect on the strength of the acid group. It is the intent of this study to fill this gap in the knowledge of amino-acid chemistry.

At about the time this study began on the effect of chelation on the strength of the uncomplexed acid group, the next two higher homologs of these dicarboxylic amino acids became commercially available. It was, therefore, decided that the problem of this research should be expanded to include all four of the acidic amino acids.

The research problem was also defined to …

A Polarographic Study Of Substituent Effects In Nickel(Ii)-Complex Ions Of Pyridine And Pyridine Derivatives, Keith Edward Fester

University of the Pacific Theses and Dissertations

The electrochemical technique of polarography was used to study the complexions formed by Ni(II) ion and pyridine compounds. It was of interest to vary the substituent group on the pyridine ring in order to observe the effects on the nickel - nitrogen coordinate bonds.

Electrocapillary Studies Of Reversible Charge Transfer V(Iii)/V(Ii) Electrode, Mohammad Ali Akhtar

University of the Pacific Theses and Dissertations

Electrocapillary equation for an ideal polarized electrode based on Gibb's adsorption equation is appropriately recast into experimentally measurable quantities in order to apply it to a reversible charge transfer electrode.

To calculate the various parameters of the equation developed, experimental details were worked out. For the measurement of Current-time relationship of a single drop, a fast response potentiostat was built by using transistorized chopped stabilized operational amplifiers and precision components in the circuitry with proper compensation for IR-drop in the cell and the electrical double layer capacity. The analysis of I-t curves was done by taking into account the composite …

Measurement Of Fluorescence Lifetimes Of Biologically Significant Compounds, Irene Adele Petz

University of the Pacific Theses and Dissertations

The purpose of this research was to measure fluorescence decay-times of several biologically significant compounds. Although various equations are available which permit one to calculate fluorescence lifetimes from spectral data, ample evidence exists which indicates such calculations are at considerable variance with experimental results.

Determination Of Flow Curves From Capillary Rise Rate Measurements, Richard Lehr Kissling

University of the Pacific Theses and Dissertations

The measurement of viscosity is a common and useful technique for investigating the mechanical behavior of many real fluids. Theoretical interpretations of viscosity measurements have been important in attempts to elucidate fundamental properties of the liquid state. Brush (6) and Bondi (3) give reviews of the current status of attempts to construct theories of liquid viscosity, and it is quite apparent from these reviews that the molecular theory of rheological phenomena is in its infancy.

In addition to the fundamental aspects of viscometry, there are many practical applications to which viscosity measurements are directed (25). One has only to scan …

Palladium And Platinum Complexes Of Substituted Cycloolefins, Gerald Brady Mccauley

University of the Pacific Theses and Dissertations

Much of the fundamental work on complexation of cycloolefins by platinum metals has been laid down by several workers and ranges from complexes of butadiene those of cyclododecatriene. The work here was chiefly a continuation of research on cycloolefin complexes which appear in papers by Kuljian and Frye (30,31,44). Most of this work on the complexes of cyclic seven, eight, and twelve carbon ligands was repeated here to insure a more complete laboratory background and for verification of previously reported literature data on these compounds. These compounds were used a s basis for comparison to original compounds developed in the …

A Polarographic Study Of Selected Metal Complex Ions Of Several P-Tosyl Amino Acids, Joseph Martin Reyes

University of the Pacific Theses and Dissertations

A polarographic study of the complexes of selected metal ions and the p-Tosyl derivatives of the amino acids; glycine, glutamic acid and lysine has been made to determine their coordination number, formula, dissociation constant and free energy of formation.

Ternary Phase Diagram Determinations Concerning Potassium Electrolyte Influence On Aqueous Solutions Of Dioxane Or Tetrahydrofuran, John Albert Mcnaney

University of the Pacific Theses and Dissertations

For the graphical representation of the mutual, partial solubilities of a·ternary system, a diagram is generally employed which is based upon the equilateral triangle, whose properties are especially felicitous for this-purpose.

In this study, the phase diagrams for the following systems were determined: potassium acetate-water-dioxane, potassium acetate-water-tetrahydrofuran, potassium benzoate-water-dioxane, potassium benzoate-watertetrahydrofuran, potassium chloride-water-tetrahydrofuran, and potassium hydroxide-water-dioxane.

The systems, potassium acetate-water-dioxane and potassium hydroxidewater-dioxane, were investigated at 25° and 85°. This study indicates that they are, to a slight degree, temperature dependent. When these systems were plotted on a mole-percentage basis, it was found that both potassium compounds have about the …

Capillary Behavior Of Viscous Liquids, Marvin De Young

University of the Pacific Theses and Dissertations

A major problem confronting every investigator who works with synthetic organic chemistry is that of the crystallization of the products obtained. This problem necessitates extensive attention both on the experimental and on the theoretical level. In order to gain an understanding of the behavior of substances in the liquid state, so as to be better able to manipulate them in procedures intended to induce crystallization from complex mixtures, considerable attention has been given to various models of the liquid state. An understanding of the nature of pure liquids would seem to be an essential prelude to any attempt to understand …

The Binary Halides Of Molybdenum(Iv) And Tungsten(Iv) And The Oxochlorides Of Tungsten(Vi), Edward Roy Epperson

University of the Pacific Theses and Dissertations

It was the purpose of this study to investigate the reaction of molybdenum and tungsten dioxides with carbon tetrachloride and bromoform (via the method of Knox and Tyree) to produce anhydrous molybdenum and tungsten tetrachlorides and bromides and to determine whether the method is a reliable one for the synthesis of these compounds. Out of this grew an investigation into the preparation of the oxochlorides of tungsten(VI) using the same preparative technique.

The results of this study are here set forth. An attempt is made to systematize the published material on the synthesis and properties of the binary halides of …