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A Theoretical Investigation Of The One– And Two–Photon Properties Of Porphyrins, Mark Masthay, Leonore A. Findsen, Brian M. Pierce, David F. Bocian, James S. Lindsey, Robert R. Birge

Chemistry Faculty Publications

The one‐ and two‐photon properties of free base porphin, free base porphin dianion, and the 2,4‐substituted diformyl and divinyl analogs of these molecules are studied using a semiempirical SCF‐MO formalism (CNDO‐π‐SCF‐MO‐PSDCI) including extensive single and double configuration interaction. Strongly two‐photon allowed states are predicted to lie in the Soret region as well as in the region between the Soret and visible bands. A number of the two‐photon allowed states in the Soret region are predicted to have two‐photon absorptivities exceeding 100×10−50 cm4 s molecule−1 photon−1. The calculations indicate that the visible (Q) states are well characterized by the …

Flow Injection And Photometric Determination Of S(Iv) In Rainwater With Pararosaniline, Frank A. Hedgecock

Retrospective Theses and Dissertations

The photometric pararosaniline (pRA) method for determination of S(IV) has been adapted to flow injection sample processing (FIA). Prominent features of the method include a limit of detection of 0.010 ppm of dissolved sulfur dioxide and a sampling rate of 20 per hour. The concentration range investigated was 0.010 to 0.200 ppm S0₂. Sequential samples were collected from two rainstorms and SO₂ concentrations were measured for 19 samples. The suppression of interference by Cr(III), Mn(II), and Fe(III) using 1,2-cyclohexylenedinitrilotetraacetic acid (CDTA) and ethylenediaminetetraacetic acid (EDTA) was investigated. A comparison of the adapted FIA method and its parent …

The Use Of Scheffe-Equivalent Equations To Predict Physical Properties Of Neoprene, Cheng Y. Loh

Retrospective Theses and Dissertations

The goal of this study is to find a more organized and directed approach to build models for mixture systems. An attempt is made to generate and then compare Scheffe (mixture) models with those generated by McGee using the ‘conventional’ method for neoprene data. The models are judged on their ability to predict physical properties of neoprene by comparing the following: predicted and actual values by inspection; the calculated % error of prediction; the squared multiple correlation coefficients; adjusted squared multiple correlation coefficients; the Fisher statistic and significance probability. Scheffe models do not have an intercept term and test statistics …

Ion Selective Electrodes Based On Aza- Substituted Crown Ethers, Lisa Ann Wellington

Retrospective Theses and Dissertations

A cation-responsive electrode system has been developed which incorporates aza-substituted crown ethers as ligands. In a novel application, uncomplexed crown ethers were used in the pelletized form for ionic transport. Electrodes have been produced which can be conditioned for a particular ion and following their use, be reconditioned and reused for other ions. Preparation method and lifetime studies are included.

The responses of two crown ethers with plasticizers were evaluated for thirteen representative cations. The concentration range covered in each evaluation was 1 x 10^-1 to 1 x 10^-7 M. For those ions exhibiting Nernstian or near-Nernstian response, …

New Synthetic Applications Of Enaminoketones, Timothy J. Buck

Retrospective Theses and Dissertations

This report discusses research concerning synthetic applications of enaminoketones. The work may be divided into four parts as follows: a) replacement of the dimethylamino group of certain enaminones by other amine groups through a simple procedure; b) formation of 3-alkyl-pyrazoles; c) formation of 2-amino-4-alkyl-pyrimidines; d) synthesis and subsequent reduction of iminium salts. The starting materials (E-1-(N,N-dimethylamino)-1-alkene-3-ones) have been condensed with hydrazine and guanidine to form pyrazoles and pyrimidines, respectively. The same starting materials have been reacted with POCl₃ in CH₂Cl₂ to produce chlorovinyliminium salts. These have then been reacted in situ with reducing agents to produce …

The Potential Energy Surface Of (Nh3)2, Z. Latajka, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Ab initio calculations at the SCF and correlated levels are carried out to characterize the potential energy surface of the NH₃ dimer. The two basis sets used are 4‐31G∗ and a larger one containing two sets of d‐functions on N centers, 6‐31G∗∗ (1p, 2d). The only minimum occurring on the surface is a cyclic C_2h structure in which the two H‐bonding protons are displaced 42° from the N‐‐N axis. The surface contains a very shallow valley along the direction leading from this geometry to a single linear H bond although …

Correction Of The Basis Set Superposition Error In Scf And Mp2 Interaction Energies. The Water Dimer, M. M. Szczesniak, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

There has been some discussion concerning whether basis set superposition error is more correctly evaluated using the full set of ghost orbitals of the partner molecule or some subset thereof. A formal treatment is presented, arguing that the full set is required at the Møller–Plesset level. Numerical support for this position is provided by calculation of the interaction energy between a pair of water molecules, using a series of moderate sized basis sets ranging from 6‐31G∗∗ to the [432/21] contraction suggested by Clementi and Habitz. These energies, at both the SCF and MP2 levels, behave erratically with respect to changes …

Electrochemistry Of Dihalogenated Nicotonic Acids In Aqueous And Aprotic Media, Ali U. Shaikh, Tappi A. Dixon, Lourie A. Battles, Frank L. Setliff

Journal of the Arkansas Academy of Science

The electrochemical reduction of several 2,5- and 5,6- dihalonicotinic acids have been studied in dimethyl sulfoxide as well as in aqueous buffers of different pH. The polarographic half-wave potentials for the reduction of these compounds in both media are reported here. The compounds appear to reduce at the carboxyl group. The presence of halogen atoms on the pyridine ring facilitates reduction.

Amphiphilic Association Structures And Some Aspects Of Foam Stability, Jia-Hwa Fang

Doctoral Dissertations

"This investigation was performed in order to study two interesting and important problems in foams.

Foam separation was studied in the model system of water - sodium octylsulfonate - decanol. The efficiency of foam separation as a function of surfactant concentration and decanol content were measured. The results were related to the association structures of amphiphiles in aqueous systems.

Foam polymerization was conducted in the amphiphilic system containing water, polymerizable surfactant and oleyl alcohol. Liquid foams were produced in one three - phase region. The location and optical pattern of liquid crystals on the foam surface were observed by photomicroscope …

Race, Sex And Occlusive Cerebrovascular Disease: A Review, L. R. Caplan, P. B. Gorelick, D. B. Hier

Chemistry Faculty Research & Creative Works

No abstract provided.

Interobserver Agreement In The Diagnosis Of Stroke Type, Cynthia R. Gross, David Shinar, Jay P. Mohr, Daniel B. Hier, Louis R. Caplan, Thomas R. Price, Philip A. Wolf, Carlos S. Kase, Irene G. Fishman, Sandra Calingo, Selma C. Kunitz

Chemistry Faculty Research & Creative Works

Interobserver Agreement is Essential to the Reliability of Clinical Data from Cooperative Studies and Provides the Foundation for Applying Research Results to Clinical Practice. in the Stroke Data Bank, a Large Cooperative Study of Stroke, We Sought to Establish the Reliability of a Key Aspect of Stroke Diagnosis: The Mechanism of Stroke. Seventeen Patients Were Evaluated by Six Neurologists. Interobserver Agreement Was Measured When Diagnosis Was based on Patient History and Neurologic Examination Only, as Well as When It Was based on Results of a Completed Workup, Including a Computed Tomographic Scan. Initial Clinical Impressions, based Solely on History and …

Solvation Changes Induced In A Lyotropic Lamellar Liquid Crystal Containing Solubilized Benzene, Anthony J.I. Ward, Shankar B. Rananavare, Stig Friberg

Chemistry Faculty Research & Creative Works

Deuterium NMR quadrupole splitting's of deuterated benzene and water were studied as a function of their composition in the aqueous lamellar phase of Penta ethylene glycol n-dodecyl ether. An interpretation of the results is given in terms of hydration changes of the poly(oxyethylene) chains related to changes in the benzene solvation and location within the head-group region. © 1986, American Chemical Society. All rights reserved.

Surfactant Association Structures And The Stability Of Emulsions And Foams, Stig Friberg, Concepcion Solans

Chemistry Faculty Research & Creative Works

Traditional surfactants in combination with water and a more hydrophobic amphiphile, such as an alcohol or a carboxylic acid, present a rich variety of colloidal association structures, both micelles and lyotropic liquid crystals. The presence of such association structures has a pronounced influence on the stability of macro dispersed systems such as emulsions and foams. A few examples of such an influence are discussed. © 1986, American Chemical Society. All rights reserved.

Influence Of Geometric Factors Of The Substrate On Hydrophilic Surface Modification Of Polyurethane Sponges By Plasma Treatment, D. L. Cho, H. Yasuda

Chemistry Faculty Research & Creative Works

The surface modification by plasma treatment occurs by consecutive processes of excitation of gas(es) and deexcitation of excited species. The deexcitation occurs primarily at the surface yielding chemical modification of the surface (nonpolymer-forming plasmas) or deposition of material (polymer-forming plasma) on the substrate surface. Because of this sequence, geometric factors of the substrate in relation to the surrounding plasma phase have crucial influence on the effectiveness of plasma treatments. Simple mathematical models were developed to illustrate the effect of geometric factors involved in plasma treatments, and experimental results obtained with porous polyurethane sponges in various sizes were examined by the …

The Synthesis And Characterization Of Some Thermally Stable Polypyrazoles And Acetylene Terminated Aspartimides, John W. Connell

Theses and Dissertations

Reactions involving the nucleophilic addition cyclization to activated acetylenes have been employed as a novel route to moderate to high molecular weight polymers. Polypyrazoles (PI to P12) have been prepared from the Michael-type addition cyclization of various aromatic dihydrazines to aromatic dipropynones in m-cresol. The aromatic dihydrazines employed were 4, 4'-dihydrazinodiphenyl ether (4,4' -DHDPE), 4,4 '-dihydrazinodiphenylmethane (4, 4'-DHDPM), and 4, 4' -dihydrazinodiphenyl sulfone (4,4'-DHDPS). The dipropynone sutilized were 1,1’- (1,4-phenylene) bis (3-phenyl- 2-propyn-l-one), (l,4 -PPPO), 1,1’ - (1, 3-phenylene) bis (3 -phenyl- 2 -propyn-l-one), (1,3-PPPO), 1,1 '-(1,4 -phenylene) bis (2 -propyn- l-one), (1,4 -PPO), and 1,1’- (1,3 -phenylene) bis (2 …

Electrochemical Investigation Of The Effects Of Temperature, Ph, And Electrolyte On The Electron Transfer Reactions Of Cytochrome C, Kent Brian Koller

Theses and Dissertations

Spectroelectrochemical and electrochemical methods have been used to investigate the characteristics of heterogeneous electron transfer between cytochrome c and indium oxide electrodes. Direct electron transfer between cytochrome c and solid electrodes is of interest due to the interfacial character of electron transfer between the protein and its membrane-bound physiological redox partners. The conformation of ferricytochrome c is affected more by changes in temperature or pH than is its reduced form, ferrocytochrome c. This difference in conformational stability is attributed to the +1 charge of the heme in ferricytochrome c that is largely embedded in the hydrophobic interior of the enzyme. …

Empirical Equations For Activity And Osmotic Coefficients, N. Ragunathan

Masters Theses

A system of equations for fitting the experimental activity and osmotic coefficients of single and mixed electrolytes in aqueous solutions has been empirically developed in the present research. The results obtained through the equations developed here are comparable to the Pitzer equations in terms of accuracy and range of fitting. The equation for activity coefficient developed in the present research compared to the Pitzer activity coefficient equation has a form which is conveinient for computational purposes. The equation for activity coefficients is ln g = -╎Z_mZ_x╎A_D[I^1/2/(1 + bI^1/2)] + E …

Studies Of Sodium Dodecylbenzenesulfonate-Water-Electrolyte Interactions, Xiaoxiang Zhu

Masters Theses

A surfactant selective electrode using a PVC membrane was constructed. A surfactant (sodium dodecylbenzene-sulfonate)-H₂O system was studied at 15°, 19°, 25°, and 40°C with the PVC electrodes, a Na⁺ selective electrode, and a conductivity bridge. Pre-micelle regions at the above temparatures were observed. The critical micelle concentrations (CMC^b) obtained by the PVC electrodes in salt-free systems are: 1.63x10^-3 M at 15°C, 1.48x10^-3 M at 19.1°C, 1.52x10^-3 M at 25°C, and 1.73x10^-3 M at 41.6°C. The CMC'c obtained by the Na⁺ electrode are: 1.62x10^-3 M at 15°C, 1.37x10^-3 M …

Characterization Of The Capsular Polysaccharides On Cell Membranes Of Rhizobium Trifolii And Three Of Its Nod- Mutants, Jesse Ardosa

Masters Theses

The ever-present specter of the inavailability of food production to increase in direct proportion to population growth haunts practically every nation of the world. As more and more tracts of land are incorporated to accommodate expanding cities, they become less available for food production. Emphasis, therefore, is placed on obtaining a higher yield per acreage planted. Since fertilization is not reliable in the long term due to an eventual depletion of raw materials for fertilizers, the ability of plants like legumes to assimilate free soil nitrogen on their own has become increasingly important [1,11,14,17]. However, the mechanisms involved are still …

Isolation And Partial Analysis Of Proteins And Polysaccharides Of Rhizobium Trifolii, Manuelito M. Ordonez

Masters Theses

The outer membrane and periplasmic proteins of Rhizobium trifolii ANU 843 and its mutants ANU 851 and ANU 845(pRt150) were isolated and analyzed by polyacrylamide gel electrophoresis (PAGE). ANU 843 is the wild type strain which possesses all the characteristics necessary for nitrogen fixation. ANU 851 has a transposon (Tn5) inserted into the nodD gene of the root hair curling region of the symbiotic plasmid. It has lost its ability to cause root hair curling and therefore can not form nodules and can not fix nitrogen. ANU 845(pRt150) harbors only the 5.5 kb root hair curling region of the …

A Non-Aqueous Lamellar Liquid Crystal With An Ionic Surfactant-Long Chain Alcohol Combination, Stig Friberg, Paul Liang, Yuh Chirn Liang, Bettye Greene, Ron Van Gilder

Chemistry Faculty Research & Creative Works

A non-aqueous lamellar liquid crystal of sodium dodecyl sulfate, decanol and glycerol was prepared and compared with its aqueous counterpart. The results show that the stability of the liquid crystal with glycerol is critically dependent on the surfactant/alcohol ratio, whereas the liquid cry. The interlayer spacing was smaller for the glycerol system than for the water system at finite amount of solvent, but the value extrapolated to zero so. © 1986.

Use Of Isomerizable N-Alkylmerocyanine Dyes To Robe Molecular Interactions Within Micellar Solubilization Sites, Kim Jason Dennis

University of the Pacific Theses and Dissertations

Effects of aqueous surfactant solutions upon cis/trans isomerization reactions of various N-alkyl-merocyanine dyes (II) were studied. Dramatic rate enhancements were found for all dyes in CTAB and SDS solutions above the CMC. CTAB solutions showed the greatest effect with some dye isomerizations catalyzed in excess of 1000-fold. Increases in either CTAB concentration or dye isomerization rates. N-methyl through N-pentyl dye isomerization rates were measured as a function of CTAB concentration and the data treated according to the pseudophase model for micellar catalysis. K_S values ranged from 198 to 2000 M^-1 for N-methyl to N-pentyl dyes, respectively. Micellar rate …

Nonadiabatic Theory Of Fine-Structure Branching Cross Sections For Na-He, Na-Ne, And Na-Ar Optical Collisions, Linda L. Vahala, P. S. Julienne, Mark D. Havey

Electrical & Computer Engineering Faculty Publications

The nonadiabatic close-coupled theory of atomic collisions in a radiation field is generalized to include electron spin and is used to consider the weak-field Na–rare-gas (RG) optical collision Na(²S_1/2)+RG+nhν μNa(²P_j)+RG+(n-1)hν. The effects of detuning and incident energy on the branching into the atomic Na 3p²P_3/2 and 3p²P_1/2 states are examined. The cross sections σ(j) are found to have a strong asymmetry between red and blue detuning as well as a complex threshold and resonance structure dependence on energy. A partial cross-section analysis …

The Association Of Nadph With The Guanine Nucleotide Exchange Factor From Rabbit Reticulocytes: A Role Of Pyridine Dinucleotides In Eukaryotic Polypeptide Chain Initiation, Jaydev N. Dholakia, Timothy C. Muesser, Charles L. Woodley, Lawrence J. Parkhurst, Albert J. Wahba

Department of Chemistry: Faculty Publications

The guanine nucleotide exchange factor (GEF) was purified to apparent homogeneity from postribosomal supernatants of rabbit reticulocytes by chromatography on DEAE-celiulose and phosphocellulose, fractionation by glycerol gradients, and chromatography on Mono S and Mono Q (Pharmacia). At the Mono S step GEF is isolated as a complex with the eukaryotic polypeptide chain initiation factor 2 (eIF-2) and is separated from this factor by column chromatography on Mono Q. An emission spectrum characteristic of a reduced pyridine dinucleotide was observed when GEF was subjected to fluorescence analysis. By both coupled enzymatic analysis and chromatography on reverse-phase or Mono Q columns, the …

Structure Of L,L-Diphenylphosphorinanium Bromide Monohydrate, J. A. Campbell, R. Larsen, R. Ekeland, Sheldon E. Cremer

Chemistry Faculty Research and Publications

No abstract provided.

Some Useful Synthetic Applications Of Gold's Reagent, John T. Gupton

Chemistry Faculty Publications

While looking for some appropriate research projects, I had been impressed by and interested in the work of Danishefsky¹ and others² regarding the use of "Eschenmoser's salt" (1). During the course of a literature search on an industrial project, we came across an article by Gold,³ which described the preparation of a rather interesting vinylogous iminium salt (2). The name assigned to this compound was [3-(dimethylamino)-2-azaprop-2-en-1-ylidene]dimethylammonium chloride. This terminology seemed a little cumbersome for routine discussions so we adopted the name "Gold's Reagent" for compound 2. Although the reagent had been prepared³ in 1960, very little …

Microemulsions With High Water Solubilizing Capacity At High Hydrocarbon Levels And Very Low Surfactant Concentrations, Raymond L. Venable, Kay Lynn Elders, Jiafu Fang

Chemistry Faculty Research & Creative Works

Phase diagrams have been determined showing the extent of the inverse micellar or microemulsion region for systems consisting of water-surfactant-cosurfactant or water-surfactant-hydrocarbon cosurfactant mixture with three surfactants and four cosurfactants. The surfactants are sodium dodecyl sulfate, sodium laurate, and tetradecyltrimethylammonium bromide while the cosurfactants are pentanol, hexanol, pentylamine, and hexylamine. Hexylamine is found to be a very effective cosurfactant giving rise to very good water solubilizing capacity at extremely low surfactant concentrations and very low cosurfactant levels at rather high initial hydrocarbon levels. © 1986.

The Mechanism Of Hydrotrope Action Of A Dicarboxylic Acid, Stig Friberg, S. B. Rananavare, D. W. Osborne

Chemistry Faculty Research & Creative Works

The mechanism of the hydro trope action of a dicarboxylic acid Mono soap was investigated by determination of the change in order parameter of the amphiphile in a lamellar liquid crystal. The results showed addition of the hydro trope considerably to reduce the order while addition of a surfactant had no effect. © 1986.

Plasma‐Substrate Interaction: Effect Of Volatile Oligomers In Silicone Rubber On Plasma Polymerization Of Fluorine‐Containing Monomers, Y. ‐S Yeh, H. Yasuda

Chemistry Faculty Research & Creative Works

The cause of the conspicuous Si content consistently observed on plasma polymers deposited on silicone rubber was investigated in this study. Plasma polymers of tetrafluoroethylene and of hexafluoroethane were deposited on the inside surface of Silastic tubings with and without oligomers by using a semicontinuous plasma polymerization reactor. This tube coating reactor is unique in the sense that the only surface which interacts with the plasma is the substrate surface (i.e., inside wall of tubing) and that plasma polymerization occurs in a very small volume of 3.3‐mm‐I.D. and 2‐cm‐long section of tubing at any given time. These two factors render …

Foams From A Three-Phase Emulsion, Hironobu Kunieda, Stig Friberg

Chemistry Faculty Research & Creative Works

Foam stability was related to phase behavior in a foamed three-phase region consisting of an aqueous solution (L1), an alcohol solution (L2) and lamellar liquid-crystalline (LC) phases in the C8H17SO3Na/C8H17OH/H2O system. The state of the system before foaming was LC/L2 + LC/L1 or L1 + L2/LC type emulsions up to a high octanol/water ratio of 77/23. In L2 + LC/L1 emulsion, the LC droplets exist separately from the alcohol droplets in an aqueous continuous medium. The viscosity of the system was enhanced with an increase in the content of dispersed phases, i.e. alcohol and/or liquid crystal phases contributing to the …