Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Chemistry

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 14941 - 14970 of 15524

Full-Text Articles in Entire DC Network

Redox Reaction Kinetics Between Cobalt(Ii)-4,4',4",4'"-Tetrasulfophthalocyanine & Iodine In Various Solvents, Byung-Soo Yu Dec 1985

Redox Reaction Kinetics Between Cobalt(Ii)-4,4',4",4'"-Tetrasulfophthalocyanine & Iodine In Various Solvents, Byung-Soo Yu

Masters Theses & Specialist Projects

Analyses of the kinetic data obtained on the redox reaction between cobalt(II)-4,4',4",4"-tetrasulfophthalocyanine [Co(II)TSPC4-] and iodine in the presence of air show three reactions in dimethylsulfoxide(DMS0), N,N-dimethylacetamide(DMA), and diethylene glycol(DEG) while there are two reactions in methanol(Me0H). Two of the three reactions in DMSO, DMA, and DEG are biphasic with one reaction in all of the solvents being too fast to be accurately measured on the Cary Model 14 spectrophotometer. When the reactant solutions are purged with argon for 40 minutes under identical conditions, the same biphasic reactions are observed in DMSO and DEG while only one of the …


Reductive Dechlorination Of Toxic Chlorocarbons, K. Grant Taylor Dec 1985

Reductive Dechlorination Of Toxic Chlorocarbons, K. Grant Taylor

KWRRI Research Reports

The sodium hydride based reducing agents were prepared the method of Caubere (Angew. Chem. Int. Ed. Engl., 1983, 22, 599-613). Reagents were prepared containing nickel, iron and zinc metals. All were effective in dechlorinating 1,3-dichlorobenzene, 4-methoxy-chlorobenzene, and arochlor 1254. Most work focused on nickel based reagents, the most active. The nickel-based reducing agent used in THF at 65°C reduced to 200 ppm 1,3-dichlorobenzene (to benzene) and arochlor 1254 (to biphenyl) to below 0.2 ppm in less than 15 minutes. A two stage reduction reduced arochlor 1254 to below a detectable level as determined by gas chromatography using f.i.d. detector. Using …


Glycation Of Amino Groups In Protein, Nancy G. Watkins, Suzanne R. Thorpe, John W. Baynes Sep 1985

Glycation Of Amino Groups In Protein, Nancy G. Watkins, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

Ribonuclease A has been used as a model protein for studying the specificity of glycation of amino groups in protein under physiological conditions (phosphate buffer, pH 7.4, 37 “C). Incubation of RNase with glucose led to an enhanced rate of inactivation of the enzyme relative to the rate of modification of lysine residues, suggesting preferential modification of active site lysine residues. Sites of glycation of RNase were identified by amino acid analysis of tryptic peptides isolated by reverse-phase high pressure liquid chromatography and phenylboronate affinity chromatography. Schiff base adducts were trapped with Na- BH&N and the a-amino group of Lys-1 …


The Survival Of Mesophilic And Thermophilic Bacteria Subjected To Uv Irradiation, Sajida A. Shaikh Aug 1985

The Survival Of Mesophilic And Thermophilic Bacteria Subjected To Uv Irradiation, Sajida A. Shaikh

Masters Theses

Survival curves were determined for the mesophile, Bacillus licheniformis and the thermophile, Bacillus stearothermophilus after subjecting the cells to ultraviolet irradiation. Cells were grown at 37°C for the mesophile and at 55°C for the thermophile.

At low UV exposure times, the thermophile was more resistant to UV irradiation (had a better survival rate) than was the case for the mesophile. At higher exposure times, the situation was reversed, the mesophile having a greater survival rate than the thermophile.

The effect of changes in the temperature during irradiation was also determined. Thermophiles were greatly affected by changes in temperature while the …


The Synthesis And Evaluation Of A New Analog Of Phencyclidine (Pcp), William H. Johnson Jr. Apr 1985

The Synthesis And Evaluation Of A New Analog Of Phencyclidine (Pcp), William H. Johnson Jr.

Chemistry & Biochemistry Theses & Dissertations

Based on an interpretation of the literature of phencyclidine (PCP) together with an examination of the relevant models or prototype structures, this research has attempted to design and synthesize a rigid analog of the phencyclidine structure. The parent ring systems suggested for this study were the 1-arnino and 2-arninornethyltetralins, 10 and, 12.

Several organic compounds, based on this design, have been prepared by classical examples of reductive alkylation reactions of the corresponding 2-hydroxyciethylene-1-tetralones, 11, and by the condensation and subsequent reductive alkylation of the 1-arninotetralin, 9. These arninomethyltetralones, 28, 29 and 30, together with an example of a substituted 1-arninotetralin, …


Influence Of Basis Set On The Calculated Properties Of (H3n–Hcl), Z. Latajka, Steve Scheiner Jan 1985

Influence Of Basis Set On The Calculated Properties Of (H3n–Hcl), Z. Latajka, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The structure of (H3N–HCl) is investigated by ab initio calculations using a number of different basis sets ranging from minimal to split valence. The effects of including a diffuse sp shell and d orbitals on Cl are considered as well. The geometries of the complex and the isolated subunits are fully optimized. Minimal basis sets (STO‐3G, STO‐6G, and MINI‐1) lead to an overestimate of the interaction between the subunits. Addition of d functions produces only a marginal improvement. The 3‐21G, 3‐21+G, MIDI‐1, and LP‐31G split‐valence sets erroneously predict an ion pair …


Thermodynamics Of Ion Association In Aqueous Fluoride Solutions. Determination Of Stability Constants For (Naf), (Mgf)+ And (Caf)+ Ion Pairs, Waldo Zamorano-Santander Jan 1985

Thermodynamics Of Ion Association In Aqueous Fluoride Solutions. Determination Of Stability Constants For (Naf), (Mgf)+ And (Caf)+ Ion Pairs, Waldo Zamorano-Santander

Masters Theses

Stoichiometric ion-association constants were determined at several ionic strengths for (NaF) over the temperature range 15-40°C and for (MgF)+ and (CaF)+ over the temperature range 25-45°C using fluoride ion selective electrode measurements.

Thermodynamic association constants, K°, were obtained through extrapolation of the stoichiometric values to infinite dilution. Values of K° for (NaF) are 1.70, 2.16 and 2.54 at 15, 25 and 40°C, respectively. The K° values for (MgF)+ are 73.4, 88.0 and 98.2, and for (CaF)+ are 13.7, 17.5 and 21.9 at 25, 35 and 45°C., respectively.

The stoichiometric association constants for (NaF) can be reproduced …


I. The Use Of Polyethers As Phase Transfer Catalysts For The Fluoroalkoxylation Of Halogenated Aromatic And Heteroaromatic Systems Ii. The Grignard Addition And Sodium Cyanoborohydride Reduction Of Arylchloropropeniminium Salts, Martin A.M. Moebus Jan 1985

I. The Use Of Polyethers As Phase Transfer Catalysts For The Fluoroalkoxylation Of Halogenated Aromatic And Heteroaromatic Systems Ii. The Grignard Addition And Sodium Cyanoborohydride Reduction Of Arylchloropropeniminium Salts, Martin A.M. Moebus

Retrospective Theses and Dissertations

This research addresses two distinct areas of synthetic organic chemistry: the use of phase transfer catalysts for the fluoroalkoxylation of activated haloaromatic and haloheteroaromatic systems, as well as the Grignard addition and sodium cyanoborohydride reduction of aryl chloropropeniminium salts. In Part I of this research, a number of macrocyclic- and linear polytethers were studied as phase transfer catalysts in the nucleophilic aromatic substitution of haloaromitc systems. The most effective catalyst was determined to be poly(ethylene glycol)-8000 and the reaction conditions were optimized for this catalyst. Subsequently isomer reactivity, effects of activating groups, effects of leaving groups, and nucleophiles were studied …


Removal Of Colloidal Silica In Simulated Seawater By A Dynamic Multi-Short-Circuited Galvanic Cell, Jan E. Osterholm, Paul W. Kramer, Hlrotsugu K. Yasuda Jan 1985

Removal Of Colloidal Silica In Simulated Seawater By A Dynamic Multi-Short-Circuited Galvanic Cell, Jan E. Osterholm, Paul W. Kramer, Hlrotsugu K. Yasuda

Chemistry Faculty Research & Creative Works

A dynamic multi-short-circuited galvanic cell (MSCGC) with Pt-AI electrodes has been used to study the removal of colloidal silica from seawater as a pretreatment step for the desalination of seawater by use of reverse osmosis. The rate of silica removal is observed to be affected by the flow rate of the solution through the cell and the dissolved oxygen content of the solution as well as by the nature of the aluminum electrode surface and the number of contact points (short circuits) between the aluminum and platinum. The total silica content is reduced by 95 % by use of this …


The Determination Of Biological Activity And Biochemical Mode Of Action For The Oxadiazole And Diacylhdrazine Insecticides, Bonnie M. Gunn Jan 1985

The Determination Of Biological Activity And Biochemical Mode Of Action For The Oxadiazole And Diacylhdrazine Insecticides, Bonnie M. Gunn

Retrospective Theses and Dissertations

This report includes the determination of activity and possible mode of action for a group of potential new insecticides. The biological screening procedure was developed using Drosophila melanogaster as the test organism while Musca domestica was used for mode of action assays. The percent kill for each compound is based on the number of eggs placed on media containing the insecticide minus the number of adults enclosed as compared to the control media reared flies. Observations were made on all stages from eggs through adults to determine time of death and if any malformations were present. These observations aided in …


Kinetics Of Reduction Of Cytochrome C Oxidase By Dithionite And The Effect Of Hydrogen Peroxide, M. Brunori, D. Bickar, J. Bonaventura, C. Bonaventura Jan 1985

Kinetics Of Reduction Of Cytochrome C Oxidase By Dithionite And The Effect Of Hydrogen Peroxide, M. Brunori, D. Bickar, J. Bonaventura, C. Bonaventura

Chemistry: Faculty Publications

The reduction of cytochrome c oxidase by dithionite was reinvestigated with a flow-flash technique and with varied enzyme preparations. Since cytochrome a3 may be defined as the heme in oxidase which can form a photolabile CO adduct in the reduced state, it is possible to follow the time course of cytochrome a3 reduction by monitoring the onset of photosensitivity. The onset of photosensitivity and the overall rate of heme reduction were compared for Yonetani and Hartzell-Beinert preparations of cytochrome c oxidase and for the enzyme isolated from blue marlin and hammer-head shark. For all of these preparations the faster phase …


Trans Diequatorially Fused 3',3'-Diphenyl-2'-Morpholinone Derivatives Of 2-Amino-2-Deoxy-D-Glucose, Julian Guardado Puentes Jan 1985

Trans Diequatorially Fused 3',3'-Diphenyl-2'-Morpholinone Derivatives Of 2-Amino-2-Deoxy-D-Glucose, Julian Guardado Puentes

University of the Pacific Theses and Dissertations

The chemistry of amino sugar compounds has been studied in the last years in connection with the study of natural products, and many of them have been isolated. 57,17,18 Amino sugars play an important role in biochemistry, forming blocks of homo- and heteropolymers and complex molecules such as microbial polysaccharides, enzymes, gangliosides, glycoproteins, and antibiotics.

This research project had the purpose of preparing a derivative of 2-amino-2-deoxy-D-glucose, with a free hydroxyl group at the anomeric carbon, with the 4,6-positions blocked with the benzylidene cyclic acetal, and the 2,3-positions being blocked by a 3,3-diphenyl-2-morpholinone ring trans diequatorially fused to the amino …


Chemical Studies On Oxomolybdenum(Vi,Iv) Complexes As Bioinorganic Models For The Molybdenum Oxidases, James Thomas Lyon Iii Jan 1985

Chemical Studies On Oxomolybdenum(Vi,Iv) Complexes As Bioinorganic Models For The Molybdenum Oxidases, James Thomas Lyon Iii

Theses and Dissertations

The synthesis, characterization, and chemical properties of Mo(VI)o2(5-X-SSP) and Mo(VI)o2(5-X-SSE), (5-X- SSP2- = 2-((5-X-salicylidene)amino)benzenethiolate; 5-X- SSE2- = 2-((5-X-salicylidene)amino)ethanethiolate; X = Br, Cl, H, CH3O), which contain tridentate (ONS) Schiff base ligands is described. The chemical properties of these molybdenum complexes are compared with those which possess tridentate (ONO) Schiff base ligands. Cyclic voltammetry was used to obtain cathodic reduction potentials (EPC) for the quasi-reversible reduction of the cis-dioxomolybdenum (VI) complexes. Although the reductions are quasi-reversible, trends are observed in EPC both within series and when different series are …


Translational Control By Adenovirus: Lack Of Virus-Associated Rna(I) During Adenovirus Infection Results In Phosphorylation Of Initiation Factor Eif-2 And Inhibition Of Protein Synthesis, John Siekierka, Thomas M. Mariano, Patricia Reichel, Michael B. Mathews Jan 1985

Translational Control By Adenovirus: Lack Of Virus-Associated Rna(I) During Adenovirus Infection Results In Phosphorylation Of Initiation Factor Eif-2 And Inhibition Of Protein Synthesis, John Siekierka, Thomas M. Mariano, Patricia Reichel, Michael B. Mathews

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

The dl331 mutant of adenovirus serotype 5 fails to produce virus-associated (VA) RNA(I), and cells infected with this mutant do not synthesize proteins efficiently at late times in infection. The translational defect occurs at the level of polypeptide chain initiation, and cell-free extracts prepared from dl331-infected cells exhibit the defect observed in vivo. Addition of either eukaryotic initiation factor 2 (eIF-2) or guanine nucleotide exchange factor (GEF) to these cell-free extracts restores translational activity, with GEF functioning more efficiently in this regard. These results suggest that cells infected with the dl331 mutant develop a translational block at the level of …


Search For New Membrane Active Substances: Synthesis Of 3-Tropanols With Alkyl, Alkenyl And Alkenynyl Group At The Bridgehead, Ramalinga Murty Dharanipragada Jan 1985

Search For New Membrane Active Substances: Synthesis Of 3-Tropanols With Alkyl, Alkenyl And Alkenynyl Group At The Bridgehead, Ramalinga Murty Dharanipragada

Graduate Theses, Dissertations, and Problem Reports (ETD)

In recent years, Witkop and coworkers have isolated several structurally unique alkaloids from the colombian frog belonging to the genera Dendrobates. These alkaloids, which occur in the defensive skin secretions of the frog have been found to be highly active venoms as well as mucosal tissue irritants towards both mammals and reptiles. Among them are three important alkaloids histrionicotoxin, isodihydrohistronicotoxin and octahydrohistronicotoxin.


A Proposal To Fertilize The Overton Arm And Gregg Basin Areas Of Lake Mead, Larry J. Paulson Nov 1984

A Proposal To Fertilize The Overton Arm And Gregg Basin Areas Of Lake Mead, Larry J. Paulson

Publications (WR)

Several limnological studies have been conducted in Lake Mead during the past decade. The recent studies clearly show that most of Lake Mead is deficient in nutrients, especially phosphorus, and very low in productivity. The reservoir-wide average total phosphorus concentration for 1981 - 1982 was only 9 mg/m3. This is below levels found In most oligotrophic lakes and reservoirs. Algal biomass, as measured by chlorophyll-a, averaged only 1.5 mg/m3. That also places Lake Mead in the oligotrophic range. Transparency, as measured by a Secchi disc, averaged 9-5 m in Lake Mead during 1981-1982. That far exceeds …


Expression Of Epstein-Barr Virus (Ebv) Dna And Cloned Dna Fragments In Human Lymphocytes Following Sendai Virus Envelope-Mediated Gene Transfer, David J. Volsky, Thomas Gross, Faruk Sinangil, Charles Kuszynski, Ronald Bartzatt, Timothy Dambaugh, Elliott Kieff Oct 1984

Expression Of Epstein-Barr Virus (Ebv) Dna And Cloned Dna Fragments In Human Lymphocytes Following Sendai Virus Envelope-Mediated Gene Transfer, David J. Volsky, Thomas Gross, Faruk Sinangil, Charles Kuszynski, Ronald Bartzatt, Timothy Dambaugh, Elliott Kieff

Chemistry Faculty Proceedings & Presentations

Purified EBV DNA and cloned DNA fragments were trapped in Sendai virus (SV) envelopes during envelope reconstitution. The DNA-loaded reconstituted envelopes (RSVE/DNA) served as gene-transfer vehicles using the capability of RSVE to fuse with normal and tumor cells. The efficiency of RSVE-mediated EBV DNA transfer into lymphoid tumor cells and fresh human lymphocytes was 5-10% of the enveloped 3H-labeled EcoRI fragment B of EBV DNA. Purified intracellular EBV (B95-8 strain) DNA induced EBV nuclear antigen (EBNA) in 0.2-1% of human lymphocytes, transiently stimulated cellular DNA synthesis, but did not fully transform cells. Cloned Sal I F1 fragment [approximately equal to …


Characterization Of Glycated Proteins By 13C Nmr Spectroscopy, Carolyn I. Neglia, Helga J. Cohen, Albert R. Garber, Suzanne R. Thorpe, John W. Baynes Sep 1984

Characterization Of Glycated Proteins By 13C Nmr Spectroscopy, Carolyn I. Neglia, Helga J. Cohen, Albert R. Garber, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

13C NMR spectroscopy has been used to characterize Amadori (ketoamine) adducts formed by reaction of [2-13C]glucose with free amino groups of protein. The spectra of glycated proteins were acquired in phosphate buffer at pH 7.4 and were interpreted by reference to the spectra of model compounds, N alpha-formyl-N epsilon-fructose-lysine and glycated poly-L-lysine (GlcPLL). The anomeric carbon region of the spectrum (approximately 90-105 ppm) of glycated cytochrome c was superimposable on that of N alpha-formyl-N epsilon-fructose-lysine, and contained three peaks characteristic of the alpha- and beta-furanose and beta-pyranose anomers of Amadori adducts to peripheral lysine residues on protein (pK alpha approximately …


26th Rocky Mountain Conference Aug 1984

26th Rocky Mountain Conference

Rocky Mountain Conference on Magnetic Resonance

Program and abstracts from the 26th annual meeting of the Rocky Mountain Conference, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, August 7-8, 1984.


Naphthalene-2,3-Dialdehyde: A Synthon To 7,9-Polymethylene-8h-Cyclohepta[B]Naphthalene-8-One And A Study Of Their Aromaticity, Edward O. Crapps Aug 1984

Naphthalene-2,3-Dialdehyde: A Synthon To 7,9-Polymethylene-8h-Cyclohepta[B]Naphthalene-8-One And A Study Of Their Aromaticity, Edward O. Crapps

Dissertations

This report describes the synthesis of naphthalene-2,3-dialdehyde, and an analytical method for determining its purity by thin layer chromatography. Subsequently, the dialdehyde was condensed with various cyclic ketones to generate a series of polymethylene bridged naphthotropones. It was found that planarity and aromaticity increase with the size of the methylene bridge, although, the bridge must contain six or more methylene groups for the latter to be true. The claim for aromaticity is supported by NMR and IR data, which indicates the positive charge for a perchlorate cation salt is delocalized over the naphthalene and tropone ring system. Furthermore, from the …


Characterization Of Trihalomethane Formation From Proteins In Chlorinated Water, Robert Aaron Kravitz Jul 1984

Characterization Of Trihalomethane Formation From Proteins In Chlorinated Water, Robert Aaron Kravitz

Chemistry & Biochemistry Theses & Dissertations

Traditionally humates have been considered the most significant precursor in the formation of trihalomethanes in finished drinking water. This study investigates another potential precursor, namely proteins. The chlorination of aqueous protein solutions yields significant levels of trihalomethanes in terms of the maximum contaminant level (MCL) of 0.100 mg/L imposed by the USEPA. Molar yields for several proteins were determined. The average yield per unit of organic carbon was 0.5% as compared to 0.8% for a humic acid studied. A model protein, bovine serum albumin, was studied extensively to ascertain the effects of total organic carbon, chlorine dose, and time on …


Derivatives Of Trifluorovinylsulfur Pentafluoride And F-(Tert-Butyl) Hypochlorite, Jo Ann Marie Canich May 1984

Derivatives Of Trifluorovinylsulfur Pentafluoride And F-(Tert-Butyl) Hypochlorite, Jo Ann Marie Canich

Dissertations and Theses

Trifluorovinylsulfur pentafluoride dimerizes to (SF5CFCF2)2 in the presence of cesium fluoride. Two derivatives of trifluorovinylsulfur pentafluoride, SF5CF(CF3)C(O)F and SF5CF(CF3)C(O)NH2, were used to prepare the new compounds, SF5CF(CF3)CO2H and SF5CF(CF3)CN, respectively. The first was prepared by reacting the SF5-acid fluoride with water, while the second involved the abstraction of water from the SF5-amide using P4O10. The attempted preparation of a bis-pentafluorosulfur ketone and a pentafluorosulfur containing acid anhydride …


Photoaffinity Labeling Of The Antimycin Binding Site In Rhodopseudomonas Sphaeroides, Emily Wilson May 1984

Photoaffinity Labeling Of The Antimycin Binding Site In Rhodopseudomonas Sphaeroides, Emily Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to identify the site of interaction of antimycin with the ubiquinone-cytochrome b-c1 oxidoreductase in the photosynthetic bacteria, Rhodopseudomonas sphaeroides. To accomplish this goal, three areas of research were undertaken: the synthesis of a radiolabeled, photoaffinity analog of antimycin, identification of the inhibitory characteristics of this analog, and the photoaffinity labeling of the antimycin binding site. All three areas were accomplished.

The major finding of this study was the identification of an 11,000 dalton polypeptide as the predominantly labeled protein. Although this polypeptide was not exclusively labeled, it was consistently labeled and showed competition …


Investigation Of Matrix Effects On The Furnace Atomic Absorption Signals Of Chromium, Nickel And Selenium, Susan Marie Viet Apr 1984

Investigation Of Matrix Effects On The Furnace Atomic Absorption Signals Of Chromium, Nickel And Selenium, Susan Marie Viet

Chemistry & Biochemistry Theses & Dissertations

The flameless atomic absorption signals of chromium, nickel and selenium are subject to matrix interferences arising from inorganic salts and anions commonly found in urine. The effects of such salts on the atomic absorption signals were investigated using Polarized Zeeman Effect background correction in conjunction with a detector/readout system capable of resolving absorbance signals in 18 msec readings. Both optical temperature control and current temperature control were employed for each analysis. Peak area, peak height, peak shape and appearance time were compared for matrix-free standards and matrix-containing standards.

The influence of the inorganic salts on the metal analyses was found …


Las Vegas Wash Multispectral Scanner Survey, T. H. Mace, M. V. Olsen, Environmental Protection Agency Feb 1984

Las Vegas Wash Multispectral Scanner Survey, T. H. Mace, M. V. Olsen, Environmental Protection Agency

Publications (WR)

At the request of the U.S. Bureau of Reclamation, Boulder City, Nevada, the U.S. Environmental Protection Agency's Environmental Monitoring Systems Laboratory at Las Vegas collected multispectral scanner imagery of Las Vegas Wash on October 1, 1982. A combined maximum likelihood classification and editing procedure was used to classify the multispectral scanner imagery into 12 categories of land cover. The classification identified four categories of marsh vegetation, one category of riparian, two categories of mixed scrub, and two desert categories. Turbid water and cultivated land formed an "other" category. Area tabulations were formed by georeferencing the classification to the Universal Transverse …


Hydrogeochemical Aspects Of Surface Mine Reclamation In The Northern Great Plains, Gerald H. Groenewold, Robert D. Koob Jan 1984

Hydrogeochemical Aspects Of Surface Mine Reclamation In The Northern Great Plains, Gerald H. Groenewold, Robert D. Koob

Office of the Provost Scholarship

Studies of several coal-mining sites in western North Dakota have resulted in the development of a hydrogeochemical model which accounts for the observed chemical characteristics of subsurface water in undisturbed settings. Critical hydrogeochemical processes include sulfide oxidation, gypsum precipitation and dissolution, carbonate mineral dissolution and cation exchange.

In the semi-arid climate of western North Dakota, the near-surface several meters of the landscape is constantly subjected to alternate wetting/drying. This mechanism is the key to hydrogeochemical evolution of both pore water in the rooting zone and subsurface water that eventually reaches the water table.

Recent refinements in the hydrogeochemical model have …


Ab Initio Comparison Of H Bonds And Li Bonds. Complexes Of Lif, Licl, Hf, And Hcl With Nh3, Z. Latajka, Steve Scheiner Jan 1984

Ab Initio Comparison Of H Bonds And Li Bonds. Complexes Of Lif, Licl, Hf, And Hcl With Nh3, Z. Latajka, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Ab initio calculations are carried out on the complexes H3N–LiF, H3N–LiCl and their analogs H3N–HF and H3N–HCl as well as the isolated subunits. Double‐zeta basis sets, augmented by two sets of polarization functions, are used in conjunction with second‐order Moller–Plesset perturbation theory (MP2) for evaluation of electron correlation effects. The Li bonds are found to be substantially stronger than their H‐bonding counterparts, due in large measure to the greater dipole moments of the LiX subunits. Correlation has a large effect on the geometry and energetics of …


Ab Initio Study Of Fh–Ph3 And Clh–Ph3 Including The Effects Of Electron Correlation, Z. Latajka, Steve Scheiner Jan 1984

Ab Initio Study Of Fh–Ph3 And Clh–Ph3 Including The Effects Of Electron Correlation, Z. Latajka, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Ab initio calculations are carried out for FH–PH3 and ClH–PH3 using a basis set including two sets of polarization functions. Electron correlation is incorporated via Møller–Plesset perturbation theory to second and (in part) to third orders. The basis set is tested and found to produce satisfactory treatments of subsystem properties including geometries and dipole moments as well as the proton affinity and inversion barrier of PH3. Electron correlation is observed to markedly enhance the interaction between PH3 and the hydrogen halides. Its contribution to the complexation energy is 30% …


A Three Part Research Report: The Synthesis Of Potential Insecticides, N-(4-Heteroaryloxybenzoyl)-N'-(2,4-Dichlorobenzoyl) Hydrazines: A Reinvestigation Of Hexamethylphosphoramide With Ketoximes; Regioselective Fluoralkoxylation And Polyfluoroalkoxylation Of Activated Dihalobenzenes And Dihaloheterocycles, Gary A. Decrescenzo Jan 1984

A Three Part Research Report: The Synthesis Of Potential Insecticides, N-(4-Heteroaryloxybenzoyl)-N'-(2,4-Dichlorobenzoyl) Hydrazines: A Reinvestigation Of Hexamethylphosphoramide With Ketoximes; Regioselective Fluoralkoxylation And Polyfluoroalkoxylation Of Activated Dihalobenzenes And Dihaloheterocycles, Gary A. Decrescenzo

Retrospective Theses and Dissertations

This report discusses research in three areas of organic synthesis: The synthesis of potential insecticides; the reinvestigation of the reaction of hexamethylphosphoramide with ketoximes; and the regioselective fluoroalkoxylation and polyfluoroalkoxylation of activated dihalobenzenes and dihaloheterocycles. In Part I, a series of N-(4-heteroaryloxybenzoyl)-N'-(2, 3-dichlorobenzoyl) hydrazines are synthesized, and attempts at cyclic dehydration to the corresponding 2, 5-disubstituted-1, 3, 4-oxadiazoles are discussed. In Part II, the synthesis of N, N-dimethyl-N'-aryl amidines by the reaction of aryl alkyl and diaryl ketoximes with HMPA is discussed. In Part III, a series of activated dihalobenzenes and dihaloheterocycles are reacted with sodium trifluoroethoxide to study the …


Effects Of N-Substituents On The Polymerization Properties Of Maleimide, Dilip R. Abayasekara Jan 1984

Effects Of N-Substituents On The Polymerization Properties Of Maleimide, Dilip R. Abayasekara

Theses and Dissertations

The effect of the amide function and the carbethoxy function on the polymerization properties of maleimide are reported. The effects of these functions on homopolymerization and copolymerization (with styrene) were examined. These electron-withdrawing groups appeared to decrease the rate of homopolymerization and increase the rate of copolymerization.

N-carbamylmaleimide and N-carbethoxymaleimide were copolymerized with styrene in 1,4 -dioxane at 60.0° C at different feed ratios to high conversion. Copolymer composition, determined by elemental analysis and 1H NMR, indicated that while 1:1 copolymers were obtained with an equimolar feed ratio, the two systems were not alternating. It is of note that the …