Physical Sciences and Mathematics Commons^™

Synthesis Of 3, 6-Dimethyl-9, 10-Bis (Trimethylsilyl) Diimine: Structural Modification Of An Electrically Conductive Organic Solid, Cynthia A. Morphet

Honors Theses

The current, intense interest in non-classical electrical conductivity and superconductivity has stimulated an equally intense effort to synthesize new materials which exhibit enhanced electrical conductivities. This thesis reports such an effort. Previous work had resulted in the formation of planar aromatic compounds capable of acting as "synthetic metals", i.e.: of conducting an electrical charge. These efforts had focused on compounds utilizing heteroatoms from Group VIA. Efforts to synthesize analogous compounds utilizing heteroatoms from Group VA had been partially successful, but were hampered by solubility considerations. This research focuses on the synthetic procedure developed to produce an analog of one of …

Spectral Studies Of Pyrene Carboxylic Acids, Jeannie Haller

Honors Theses

The pKa and pKa* of 1-pyrenecarboxylic acid (PCA) in a 50% ethanol/water solvent were experimentally (letermined to be 4.3 and 5.2, respectively. The pK8 of pyrene acrylic acid (PAA) in the same solvent was experimentally determined to be 4.6. An excited state equilibrium was not reached at the buffer concentrations used for the pKa* analysis; therefore, a valid value for the pKa* can not be reported at this time, but taking both the experimental results and the calculated pK8.'s into account, it appears that the pKa* of PAA is in the range 6.6 < pKa* < 7.4. The fluorescence of PCA, PAA, and 1-anthroic acid (1-AA) were studied as a function of solvent. The fluorescence of PCA was solvent independent- small spectral shifts as well as the retention of structure were observed in solvents of varying polarity. The fluorescence of 1-AA and PAA exhibited a solvent dependence. The results of both the pKa analysis and the fluorescence studies indicate that the S0 and the S1 states of PCA have a similar geometry, but that the geometry of the S0 and the S1 states of PAA differ. The change in geometry may be the rotation of the carboxyl group from its nearly perpendicular position with the ring in the S0 state to a more coplanar position with the ring in the S1 state. The effects of hydrogen bonding in hexafluoroisopropanol on the spectral properties of PAA were studied, and the results of the studies indicate that PAA forms a hydrogen-bonded complex with hexafluoroisopropanol in both the ground and the excited states.

Determination Of The Kinetic And Thermodynamic Properties For Bisulfite Addition To: Acetophenone, 2-Chloroacetophenone And Trans-Cinnamaldehyde, Laurie Ann Le Tarte

Honors Theses

The equilibrium constants for bisulfite addition to acetophenone, 2-choloroacetophenone and trans-cinnamaldehyde were determined using an ultraviolet spectrophotometric method. The absorbance of the carbonyl compound was monitored as aliquots of a bisulfite solution were added to the reaction cell. By plotting 1/A versus [HSO3-], and dividing the slope by the intercept, it was possible to determine Keq. All determinations were made at pH 4.66 and ionic strength 1.0. By determining Keq at various temperatures it was also possible to determine ΔH° and ΔS°. The equilibrium constants for bisulfite addition to: acetophenone, 2-choloracetophenone and trans-cinnamaldehyde, were determined to be: 5.8 M-1, 53 …

The Synthesis Of Homoallylic Alcohols Through Diasteriomeric Transition States, Jeffrey Lee Osofsky

Honors Theses

Theoretically, optically active homoallylic alcohols can be synthesized by reacting an optically active organotin with an aldehyde in the presence of a Lewis acid. It is expected that the chirality of the organotin will induce one diastereomeric transition state which will have a significantly reduced activation energy than the transition state of the other diastereomer. If the difference between the two activation energies is substantial enough, the transition state with the lower activation energy will be preferred over the other transition state. If the preference is absolute one completely pure alcohol enantiomer will be produced. If there is a preference, …

Making A Rainbow Workstation For A Chemistry Lab, John D. Bak

Honors Theses

Chemical kinetics is the study of how quickly and by what means chemical reactions proceed. Some reactions are so fast and complicated that data must be taken very quickly and then lengthy calculations must be done to get results. Computers speed these studies greatly. The system to he described uses a DEC-Rainbow microcomputer as a terminal for a workstation. The system may collect 8k of buffered data at a rate of 1MHz and then upload the data to a VAX for analysis using the same Rainbow u a graphics terminal. The program for data analysis, called KinSim, will then accept …

Chirality Transfer In The Synthesis Of Homoallylic Alcohols, Simon Paul Drew

Honors Theses

Previous studies on the reaction of the optically active organotin, diallylisopropylmyrtanyltin, to produce homoallylic alcohols, using boron trifluoride as a Lewis acid, produced racemic mixtures regardless of the aldehyde used.1 In this experiment bromine was attached to the tin atom in allylmyrtanylphenyltin bromide, letting tin become an internal Lewis acid. Benzaldehyde was reacted with this compound to see it a single optically active product could be synthesized. After the alcohol had been separated out using vacuum distillation, the optical rotation of the product was taken and showed no appreciable rotation; thus a racemic mixture was produced.

Determination Of The Kinetic And Thermodynamic Properties For Bisulfite Addition To: Acetophenone, 2-Chloroacetophenone And Trans-Cinnamaldehyde, Laurie Ann Letarte

Honors Theses

The equilibrium constants for bisulfite addition to acetophenone, 2-choloroacetophenone and trans-cinnamaldehyde were determined using an ultraviolet spectrophotometric method. The absorbance of the carbonyl compound was monitored as aliquots of a bisulfite solution were added to the reaction cell. By plotting 1/A versus [HSO3-], and dividing the slope by the intercept, it was possible to determine Keq. All determinations were made at pH 4.66 and ionic strength 1.0. By determining Keq at various temperatures it was also possible to determine ΔH° and ΔS°. The equilibrium constants for bisulfite addition to: acetophenone, 2-choloracetophenone and trans-cinnamaldehyde, were determined to be: 5.8 M-1, 53 …

Equilibrium Constant Determination For Bisulfite Addition To Aromatic Aldehydes, Daniel Y. Choi

Honors Theses

Equilibrium constants for bisulfite addition to benzaldehyde and its derivatives were determined by a spectrophotometric method developed by Kokesh and Hall. The concentration of the benzaldehyde derivative was monitored by UV as aliquots of a bisulfite solution are added to a buffered solution of the aldehyde. Additional data on ΔH° and ΔS° for the reactions were derived from the temperature variation of the equilibrium constants. For benzaldehyde, the reaction had an equilibrium constant at 25°C of 6.2 x 103 M-1, a ΔH° of -54.3 kJ/mol, and a ΔS° of -111 J/Mol·K. o-Tolualdehyde exhibited a lower Keq of 2.4 x 103 …

The Synthesis Of Homoallylic Alcohols Through Diasteriomeric Transition States, Jeffrey Lee Osofsky

Honors Theses

Theoretically, optically active homoallylic alcohols can be synthesized by reacting an optically active organotin with an aldehyde in the presence of a Lewis acid. It is expected that the chirality of the organotin will induce one diastereomeric transition state which will have a significantly reduced activation energy than the transition state of the other diastereomer. If the difference between the two activation energies is substantial enough, the transition state with the lower activation energy will be preferred over the other transition state. If the preference is absolute one completely pure alcohol enantiomer will be produced. If there is a preference, …

Fluoride As A Therapeutic Drug In Osteoporosis Treatment, Rita Priyadarshani Francis

Honors Theses

The use of fluoride as a therapeutic drug is not a novel idea. Studies dealing with the effects of fluoride on the skeletal system date back to the late 1960's. This paper will define osteoporosis, examine methods of detection, and will discuss various methods of treatment with emphasis on the use of fluoride supplements in the form of tablets or fluorinated drinking water.

Search For Isotope Effect In Superconducting Y-Ba-Cu-O, L C. Bourne, M F. Crommie, A Zettl, Hans Conrad Zur Loye, S W. Keller, K L. Leary, Angelica M. Stacy, K J. Chang, Marvin L. Cohen, Donald E. Morris

Faculty Publications

An isotope effect has been searched for in the high-T_c, superconductor YBa₂Cu₃0_{7 —b} through substitution of ¹⁸0 for ¹⁶O. No shift in the superconducting transition temperature T, is observed by electrical resistivity or magnetic susceptibility measurements. We discuss the implications of this result for mechanisms of superconductivity in the high-T, oxides.

Effect Of Phosphate On The Kinetics And Specificity Of Glycation Of Protein, Nancy G. Watkins, Carolyn I. Neglia-Fisher, Daniel G. Dyer, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

The glycation (nonenzymatic glycosylation) of several proteins was studied in various buffiner os rder to assess the effects of buffering ions on the kinetics and specificity of glycation of protein. Incubation of RNase with glucose in phosphate buffer resulted in inactivation of the enzyme because of preferential modification of lysine residues ino r near the activsei te. In contrast, in the cationic buffers, 3-(N-morpholino)propanesulfonic acid and 3-(N-tris(hydroxymethyl)rnethylamino)- 2-hydroxypropanesulfonica cid, the kineticso f glycation of RNase were decreased 2- to 3-fold, there was a decrease in glycation of active site versus peripheral lysines, and the enzyme was resistant to inactivation by …

Direct Coal Liquefaction Using Bis(Dihydrobis(1-Pyrazolyl)Borate)Nickel (Ii) As A Catalyst, Pong Kau Yuen

Theses (Pre-2016)

The direct coal liquefaction of Illinois Number Six River King coal using bis(dihydrobis(l-pyrazolyl)borate)nickel (II) as a catalyst in SRC II (a distillate at 240-450°C) was evaluated at times of 15 minutes. Each run was carried out in a 300 ml magnedrive autoclave reactor under an initial hydrogen pressure of 900-1200 psig and/or at 425-475°C. In case of different hydrogen pressures, the tetrahydrofuran (THF) and cyclohexane conversions increased with increased hydrogen pressure. At the two temperatures of 425°C and 475°C the cyclohexane conversion increased with the increased temperature but the THF conversion decreased. The effects of different solvents and heating-rate of …

Electrochemical Reduction Of 1,1,4,4-Tetraphenylbutatriene, Tsu-Yu Chen, Mark Anderson, Dennis Peters

Mark R. Anderson

Polarograms and cyclic voltammograms for reduction of 1,1,4,4-tetraphenylbutatriene at mercury electrodes in dimethylformamide containing tetra-n-butylammonium perchlorate exhibit four waves; the first and second waves are due to stepwise formation of the radical anion and dianion of the starting material, whereas the third and fourth waves are attributable to reduction of 1,1,4,4-tetraphenyl-1,2-butadiene and 1,1,4,4-tetraphenyl-1-butene, respectively. Electrolysis of 1,1,4,4-tetraphenylbutatriene at potentials corresponding to the second wave yields 1,1,4,4-tetraphenyl-1,3-butadiene exclusively; at a slightly more negative potential, the latter undergoes reduction to 1,1,4,4-tetraphenyl-1-butene. When 1,1,4,4-tetraphenylbutatriene is electrolyzed in the presence of glacial acetic acid and at any potential on the first or second wave, …

Rise To Power Of Senator Joseph R. Mccarthy: Reflections Of The Cold War Mccarthy Era In American Film, Scott Lainer

Honors Theses

The common bond between much of the film industry and Joseph McCarthy was insecurity and the drive for national approval. If one grasps the specific characteristics of McCarthy the man, and the methods of these politically "inspired" movies, we can to better place the period into context and acknowledge the fact that, if the citizenry is not aware, and is again caught by an ever-building wave of trickle down sentiment, the 1950s might not prove to be an isolated period in American history. Insecurity was not a fifties novelty. It still exists, and could potentially escalate anti-Communist policy and sentiment …

Las Vegas Wash And Lake Mead Proposed Water Quality Standards: Revisions And Rationale, State Of Nevada: Division Of Environmental Protection

Publications (WR)

Rationale of review and for proposed changes to the Nevada Pollution Control Regulations (NAC 445.1354, 445.1355, 445.1356, 455.1367, 445.1352, 445.1353, 445.1350, 445.1351) before the State Environmental Commission on June 23 and 24, 1987.

Raw Nutrient Data, Leanna Gail

Publications (WR)

Data collected at various stations around Lake Mead. Includes information about substances present in various water samples.

The Aminolysis Of N-Hydroxysuccinimide Esters. A Structure-Reactivity Study, Gary W. Cline, Samir B. Hanna

Chemistry Faculty Research & Creative Works

Twelve amines, which vary substantially in basicity and in steric environment around N, have been allowed to compete—in anhydrous dioxane solution—in the aminolysis of the N-hydroxysuccinimide esters of unsubstituted, p-OCH₃, p-N0₂, and 3,5-(N0₂)₂ benzoic acids. The amines, which encompass a basicity range of 6.5 pk units, display a 10000-fold variation in reactivity in their reaction with the p-N0₂ester. for the sterically unhindered amines, a Bronsted-type plot of log k_obsdvs. pK_a has a slope of ~0.7. The data fit a model (Satterthwait, A. C.; Jencks, W. P. J. Am. …

University Of Missouri--Rolla Cloud Simulation Facility: Proto Ii Chamber, Daniel R. White, James L. Kassner, John C. Carstens, Donald E. Hagen, John L. Schmitt, Darryl J. Alofs, Alfred Raymond Hopkins, Max B. Trueblood, Max W. Alcorn, William L. Walker

Physics Faculty Research & Creative Works

The Graduate Center for Cloud Physics Research at UMR has developed a cloud simulation facility to study phenomena occurring in terrestrial clouds and fogs. The facility consists of a pair of precision cooled-wall expansion chambers along with extensive supporting equipment. The smaller of these chambers, described in this article, is fully operational, and is capable of simulating a broad range of in-cloud thermodynamic conditions. It is currently being used to study water drop growth and evaporation for drops nucleated (activated) on well-characterized aerosol particles. Measurements have been made not only for continuous expansions (simulated updraft) but also for cyclic conditions, …

Synthetic Studies Toward B-Alkylthiolanthionines, Hwa-Ok Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Synthetic routes toward a B-alkylthiolanthionine derivative, as found in the quinomycin depsipeptide antibiotics, have been studied through a sequence involving as the key intermediates and steps (a) (S) - Z-[(benzyloxycarbonyl)amino]-3,3-dimethoxy-l-propanol (2), prepared from N-benzyloxycarbonyl-L-serine in 3 or 4 steps, (b) N-benzyloxycarbonyl- 0 - tetrahydropyranyl-B,B-(ethylsulfinylethylthio)-alaninol (4a), converted from 2, and (c) attempted Lewis acid catalyzed replacement of alkylsulfinyl function by thiol moiety of cysteine, which gave undesired products. Stability of protecting groups used in this study, which are N,0-isopropylidenyl and tetrahydropyranyl functions in N-protected-L-serinol 20 or 26, under acidic conditions was found to play an important role in determining the optical …

Light Charged Particle Emission In 485 Mev56fe + 197au Reactions: Correlations With Heavy Fragments And Relationships To Spin And Lifetime, David J. Moses, Morton Kaplan, M. Kildir, D. R.G. Logan, G. La Rana, W. E. Parker, R. Lacey, Graham F. Peaslee, John M. Alexander, N. N. Ajitanand, Louis C. Vaz, M. S. Zisman

Faculty Publications

Emission of 4He and 1H has been studied in reactions of 485 MeV 56Fe + 197Au, using low-threshold detector arrays for light charged particles, and two heavy-fragment trigger detectors placed at symmetrically opposite angles with respect to the beam direction. The light charged particles were measured both in singles and in coincidence with heavy products of deeply inelastic and fission reactions detected near the grazing angle. Statistical model analyses of the data show that most of the 4He/1H intensity is due to evaporation from energy equilibrated emitters both in deeply inelastic and fission reactions. In deeply inelastic reactions, the observed …

Heats Of Formation For Third-Period Hydrides: Test Of An Extended Basis Set, Mark S. Gordon, John Heitzinger

Mark S. Gordon

The extended basis set developed by McLean and Chandler for third-period atoms is combined with the -311G hydrogen basis and augmented by polarization functions to predict the heats of formation of third-period hydrides at the full MP4 computational level. The calculated heats of formation are at least as accurate as those predicted for second-row hydrides by using MP4/6-311G(d,p) wave functions, with a root mean square error of approximately 4 kcaljmol.

The Preparation And Reaction Of Novel Glycosyl Ureas And Thioureas, Robert Scott Johnson

Masters Theses

No abstract provided.

Studies Of Radiation Effects In Three High Polymers, Heidi Rene-Mitchell Ries

Physics Theses & Dissertations

Three high polymers, Mylar®, Ultem®, and Kapton®, were irradiated to total doses of 1, 5, and 9.5 gigarad using 1-MeV electrons. The glass transition temperatures (T_g) of the materials before and after irradiation were measured using an AC electrical dissipation factor technique. From the T_g data, it was found that the electron radiation at these total doses results in net chain scissioning in Mylar and net crosslinking in Ultem, while self-mending is predominant in Kapton. The dielectric constant was measured before and after irradiation, but no significant changes due to irradiation were observed. Electron paramagnetic resonance (EPR) …

Electrochemical Reduction Of Phenylpropadiene At Mercury Cathodes In Dimethylformamide: Isomerization Of The Allene To 1-Phenyl-1-Propyne, Tsu-Yu Chen, Mark Anderson, Steven Grossman, Dennis Peters

Mark R. Anderson

Polarograms and cyclic voltammograms exhibit two waves for reduction of phenylpropadiene at a mercury electrode in dimethylformamide containing tetra-n-butylammonium perchlorate, the f i t wave signals reduction of phenylpropadiene to 1-phenyl-1-propene and the second wave is attributable to reduction of 1-phenyl-1-propene to 1-phenylpropane. However, the fmt wave is abnormally small because phenylpropadiene undergoes substantial rearrangement to 1-phenyl-1-propyne, which is reducible to 1-phenylpropane at nearly the same potential as 1-phenyl-1-propene. Controlled-potential electrolyses of phenylpropadiene, 1-phenyl-1-propene, and 1-phenyl-1-propyne at mercury pool cathodes have verified the processes elucidated by means of polarography and cyclic voltammetry. In the presence of diethyl malonate (a proton …

Ground-State Potential Energy Surface Of Phosphine Oxide, Jerry A. Boatz, Michael W. Schmidt, Mark S. Gordon

Mark S. Gordon

A network of elimination reactions of H3PO in its ground state is examined by using ab initio (3-21G* and 6-31G** with MP3 perturbation corrections) wave functions. In addition to the eliminations, several isomerizations and internal rotations of the parent compound and its fragments are investigated. The insertion and reactive scattering reactions of H2 + HPO, which are characterized more fully with MP4(SDTQ) perturbation corrections, are followed by using the intrinsic reaction coordinate and energy-localized orbitals.

Insertion Of Methylene Into Ethane And Cyclopropane, Mark S. Gordon, J. A. Boatz, David R. Gano, Marie G. Friederichs

Mark S. Gordon

The insertions of methylene into the CH and CC bonds of ethane and into a CC bond of cyclopropane are calculated by using third-order perturbation theory with the 6-31G(d) basis set. At this level of theory, the barriers for these reactions are predicted to be 0.2, 46.0, and 2.2 kcaljmol, respectively. Thus, the introduction of strain has a dramatic effect on the barrier to insertion into a heavy atom-heavy atom bond.

Potential Energy Surfaces For Polyatomic Reaction Dynamics, Donald G. Truhlar, Rozeanne Steckler, Mark S. Gordon

Mark S. Gordon

The last few years have seen an explosive growth of interest in detailed studies of polyatomic reaction dynamics. Improved experimental techniques, more powerful semiclassical dynamical methods, and accurate electronic structure capabilities have all combined to focus attention on detailed dynamical questions for larger and larger systems. Many of these questions have previously been tackled primarily for atom-diatom or diatom-diatom collisions or isolated triatomics. 1- 5 Although of course the final word on such simpler systems has not been said (and never will be), we will focus in the present review on more complicated cases. Thus the "polyatomic" in the title …

Maine Acid Rain Study : Reports, Maine Department Of Environmental Protection

Maine Collection

Maine Acid Rain Study : Reports

Maine Department of Environmental Protection, Augusta, Maine (February, 1987).

Contents: Acid Rain Precursor Inventory and Evaluation / Modeled Sulfur Deposition in Maine / High Elevation Lake Monitoring in Maine

Molecular Properties Of Cetiedil And Its Interactions With Human Erythrocytes, Chakravarthy Narasimhan

Dissertations

No abstract provided.