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Thesis (Ph. D.)--Oregon Graduate Center, 1980.

Ph.D. / Inorganic Chemistry / Copper (I) forms π complexes with olefin-containing metal complexes in aqueous solution. Reduction of a series of pyridinepentaammineruthenium (III) ions, where L is a pyridine or 4-substituted pyridines, was studied. For the (NH[subscript 3]) [subscript 5] Ru (III)-4-viny1pyridine ion it is possible to measure separately preequilibrium binuclear ion formation and electron transfer. The electron transfer pathway is determined to be intramolecular from comparison with rate behavior of (NH[subscript 3]) [subscript 5] (III)-4-ethylpyridine, Cu (I) and (NH[subscript 3]) [subscript 5] (III)-pyridine, Cu (I) redox pairs. Rate parameters are also determined for the reverse reaction. Cu (II) catalyzed autoxidation of the (NH[subscript 3]) [subscript 5] (II) - 4-vinylpyridine ion. The redox equilibrium constant determined from the kinetic data agrees reasonably with that calculated from the redox potentials of the reactants. Qualitative models have been advanced from which it is suggested that the entropy of activation gives a measure of the probability for electron transfer in the activated complex, values near zero indicating that electron-tunneling is not rate-limiting. Cu(I)-olefin containing binuclear ions of (NH[subscript 3])[subscript 5]Co(III)L, where L is an alkylpyridine or alkylamine, undergo efficient intramolecular electron transfer when irradiated in the Cu(I)-olefin(n*) absorption band. The results of photoredox studies of a series of alkylamine and alkylpyridine containing binuclear ions are reported. The quantum yields for Co (II) production is shown to falloff monotonically for increasing number of methylene carbons in the chain. Binuclear ions containing polyisoprenyl bridging ligands were also investigated. Mixed solvent studies show decreased quantum yield with increasing ethanol content of the aqueous media. Medium and chain configuration effects are discussed.

Electron scattering cross sections have been computed for pyridine and pyrimidine using the static-exchange approximation with model potential to account for dynamic electron correlation. To obtain well-converged orbitals, we have expanded all partial waves to a maximum angular momentum of l = 60 for both targets. We have obtained total cross sections for electron scattering energies to 20 eV. Both targets display similar features, namely a dipole-induced increase in the integrated cross section at scattering energies below 5 eV, and peaks corresponding to resonances in b1, a2, and b1 symmetries. These resonances were investigated through a Siegert eigenstate analysis and Breit-Wigner fit of the SECP eigenphase sums. They were also compared to the virtual orbitals obtained from a minimum basis set Hartree-Fock calculation on both targets. We consider electron scattering resonances from cis-diamminedichloroplatinum, [Pt(NH3)2Cl2], the ligand molecular species Cl2 (1Sigma+g ), and the isolated transition metal center Pt in a nondegenerate atomic state (1S) at the SECP level of theory. As a rigorous comparison to the single-state, single-configuration SECP level results of these smaller, yet electron dense targets, we have also considered scattering from ground state Cl2 and Pt in the 1S and 3D states in the multichannel configuration-interaction (MCCI) approximation originally developed for photoionization for scattering up to 10 eV. Photoionization cross sections and angular distributions in the recoil frame (RFPAD) and molecular frame (MFPAD) have been computed for inner-shell C 1s and Cl 2p ionization from the chloroalkanes chloromethane and chloroethane, with ionization leading to a variety of ionic fragment states. We have also computed valence level ionization from the nitro molecule nitromethane CH3NO2 leading to the dissociation of the CN bond. All of these calculations were performed in the frozen-core Hartree-Fock approximation. Even at this level of theory, we obtain computed results that compare well to the photoelectronphotoion coincidence measurements. The fullerene C20 is the smallest fullerene predicted to exist, with most relevant structural calculations suggesting the reduction of the icosahedral symmetry into one in which the target species possesses at maximum only a dihedral axis. We have computed positron scattering cross sections for the molecule in two low-symmetry structural isomers Ci and C2, within the HF approximation. Density functional expressions were used to incorporate important positron-electron interactions within the calculation. We have found similar cross sections and resonance features for both isomers, including a positron scattering resonance whose density is found within the framework of the fullerene cluster.

Structural determinations and electrochemical properties in the series of multinuclear ferrocenyl¡Vethynyl complexes with formula [(£b5-C5H5)(P2)MII-C¡ÝC-(fc)n-C¡ÝC-MII(P2)(£b5-C5H5)] (fc = ferrocenyl; M = Fe(II), Os(II); P2 = Ph2PCH2CH2PPh2 (dppe)) are reported. These complexes undergo sequential reversible oxidation events from 0.0 to 1.0 V referred to the Ag/AgCl electrode in anhydrous CH2Cl2 solution and the low-potential waves have been assigned to the two end-capped metallic centers. The magnitude of the electronic coupling between the two terminal metallic centers in the series of complexes was estimated by the electrochemical technique. Based on the correlation between the ¡µE1/2 values and the second redox potentials of the end-capping metallic centers in the series of complexes, a qualitative explanation for the difference of the electronic coupling is given. Furthermore, we attempt to fabricate the SAMs of ferrocenyl-ethynyl molecules on gold surface and confirmed by XPS spectrum and the RAIR spectrum. CV and CA electrochemistry technique was employed in studied electron transfer rate (k).

Society's growing demands for energy results in rapid increase in oil consumption and motivates us to make unconventional resources conventional resources. There are enormous amounts of heavy oil reserves in the world but the lack of cost effective technologies either for extraction, transportation, or refinery upgrading hinders the development of heavy oil reserves. One of the critical problems with heavy oil and bitumen is that they require large amounts of thermal energy and expensive catalysts to upgrade. This thesis demonstrates that electron beam (E-Beam) heavy oil upgrading, which uses unique features of E-Beam irradiation, may be used to improve conventional heavy oil upgrading. E-Beam processing lowers the thermal energy requirements and could sharply reduce the investment in catalysts. The design of the facilities can be simpler and will contribute to lowering the costs of transporting and processing heavy oil and bitumen. E-Beam technology uses the high kinetic energy of fast electrons, which not only transfer their energy but also interact with hydrocarbons to break the heavy molecules with lower thermal energy. In this work, we conducted three major stages to evaluate the applicability of E-Beam for heavy oil upgrading. First, we conducted laboratory experiments to investigate the effects of E-Beam on hydrocarbons. To do so, we used a Van de Graff accelerator, which generates the high kinetic energy of electrons, and a laboratory scale apparatus to investigate extensively how radiation effects hydrocarbons. Second, we studied the energy transfer mechanism of E-Beam upgrading to optimize the process. Third, we conducted a preliminary economic analysis based on energy consumption and compared the economics of E-Beam upgrading with conventional upgrading. The results of our study are very encouraging. From the experiments we found that E-Beam effect on hydrocarbon is significant. We used less thermal energy for distillation of n-hexadecane (n-C16) and naphtha with E-Beam. The results of experiments with asphaltene indicate that E-Beam enhances the decomposition of heavy hydrocarbon molecules and improves the quality of upgraded hydrocarbon. From the study of energy transfer mechanism, we estimated heat loss, fluid movement, and radiation energy distribution during the reaction. The results of our economic evaluation show that E-Beam upgrading appears to be economically feasible in petroleum industry applications. These results indicate significant potential for the application of E-Beam technology throughout the petroleum industry, particularly near production facilities, transportation pipelines, and refining industry.

A range of shortwave frequencies will be returned to earth by the ionosphere such that long-distance shortwave communication is accomplished. Because of ionospheric variations, operation parameters are not the same in different time duration. We must select optimized parameters with the aim of utilizing the ionosphere effectively for shortwave radio communications. Shortwave propagation prediction programs can provide such information. Empirical models are often used to represent the variations of the electron density with height in the ionosphere, since radio propagations are concerned with electron density. We develop a graphical user interface based on VOACAP that is one of the most widely used prediction programs. We also improve the electron density model in VOACAP. A gradient discontinuity occurs in the original parabolic ionospheric model. We incorporate an electron density model that does not contain any gradient discontinuities. In this model the electron density profile is composed of three segments: (1) a cosine F2 layer; (2) an E-F layer comprising a secant function, and optional cosine function to provide an F1 ledge (3) a parabolic E layer. Compared with experimental data, our modified model results in more accurate predictions.

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The E-beam curable BMI resin systems and phenylethynyl terminated AFR-PEPA-4 oligomer together with an imide model compound N-phenyl-[4-(phenylethynyl) phthalimide] were synthesized and characterized. E-beam exposure cannot propagate the polymerization of BMI system until the temperature goes up to 100oC. However, a small amount of oligomers may be generated from solid-state cure reaction under low E-beam intensity radiation. Higher intensity E-beam at 40 kGy per pass can give above 75% reaction conversion of BMI with thermal cure mechanism involved. NVP is a good reactive diluent for BMI resin. The cure extents of BMI/NVP increase with the increase of the dosage and applied dosage per pass. The reaction rate is much higher at the beginning of the E-beam cure and slows down after 2 dose passes due to diffusion control. Free radical initiator dicumyl peroxide can accelerate the reaction rate at the beginning of E-beam cure reaction but doesn’t affect final cure conversion very much. According to the results from FT-IR, 200 kGy total dosage E- beam exposure at 10 kGy per pass can give 70% reaction conversion of BMI/NVP with the temperature rise no more than 50oC. The product has a Tg of 180oC. The predicted ultimate Tg of cured AFR-PEPA-4 polyimide is found to be 437.2oC by simulation of DSC Tg as a function of cure. The activation energy of thermal cure reaction of AFR-PEPA-4 oligomer is 142.6 ± 10.0 kJ/mol with the kinetic order of 1 when the reaction conversion is less than 80%. The kinetics analysis of the thermal cure of N-phenyl-[4-(phenylethynyl) phthalimide] was determined by FT-IR spectroscopy by following the absorbance of the phenylethynyl triple bond and conjugated bonds. The thermal crosslinking of N-phenyl-[4-(phenylethynyl) phthalimide] through phenylethynyl addition reaction has a reaction order of 0.95 and an activation energy of 173.5 ± 8.2 kJ/mol. The conjugated bond addition reactions have a lower reaction order of 0.94 and lower activation energy (102.7 ± 15.9 kJ/mol). The cure reaction of N-phenyl-[4-(phenylethynyl) phthalimide] can be described as a fast first-order reaction stage followed by a slow second stage that is kinetically controlled by diffusion.