Physical Sciences and Mathematics Commons^™

Reactions Of Hydroxylamine With Metal Porphyrins, In Kyu Choi, Yanming Liu, Zhongcheng Wei, Michael D. Ryan

Chemistry Faculty Research and Publications

The reaction of hydroxylamine with a series of metal porphyrins was examined in methanol/chloroform media. The reductive nitrosylation reaction was observed for the manganese and iron porphyrins, leading to a nitrosyl complex that precipitated out of the solution in good isolatable yield (80−90%). This reaction could be used synthetically for the generation of iron and manganese porphyrin nitrosyl complexes and was particularly useful for making isotopically labeled nitrosyl complexes. On the other hand, Co^II(TPP) and Cr(TPP)(Cl) did not react with hydroxylamine under anaerobic conditions. With trace amounts of oxygen, the reaction of Co^II(TPP) with hydroxylamine led …

Tb164: Precipitation Chemistry At The Greenville, Maine, Nadp/Ntn Station, Ivan J. Fernandez, Llew Wortman

Technical Bulletins

This report details results from the Greenville, Maine, NADP/NTN site supported by the Maine Agricultural and Forest Experiment Station. The site is located in Piscataquis County at 69°39'52" longitude and 45°29'23" latitude at approximately 322 m elevation. The site consists of a single Aerochem Metrics® Automatic Sensing Wet/Dry Precipitation Collector that provides samples for chemical analysis and a Belfort® Recording Rain Gage and Event Recorder for accurate determinations of precipitation volume. Samples are collected every Tuesday morning 52 weeks a year.

Monte Carlo Simulation Of The Solid To Superliquid Phase Transition Of Langmuir Monolayers. Ii. Characteristics Of Phase Transition, M.D. Gibson, D.R. Swanson, Craig J. Eckhardt, Xiao Cheng Zeng

Craig J. Eckhardt Publications

The restricted-to-free rotator phase transition of fatty acid monolayers has been modeled using a potential which represents the amphiphiles as planar cross sections of fourfold symmetry. Using much larger system sizes than paper I [D. R. Swanson, R. J. Hardy, and C. J. Eckhardt, J. Chem. Phys. 99, 8194 (1993)], Monte Carlo simulations of the isobaric–isothermal ensemble of model systems with varied number of objects were undertaken to study the effect of system size on the characteristics and order of the phase transition. A peak in the specific heat vs temperature curve was observed near the transition. For each system …

44. Vogl Receives Honorary Doctoral Degree From Osaka University, Koichi Hatada

Otto Vogl

No abstract provided.

Quantitation Of Ethidium-Stained Closed Circular Dna In Agarose Gels, Michael F. Shubsda, Jerry Goodisman, James C. Dabrowiak

Chemistry - All Scholarship

The fluorescence of ethidium bromide (EB) bound to equimolar amounts of supercoiled form I and unstrained linear form III pBR322, SV40 and PM2 DNA in agarose gels has been measured by scanning a photographic negative of the gel with a microdensitometer. For SV40 and PM2 DNA, commonly used staining conditions cause both forms, i.e. linear and supercoiled, to fluoresce to the same extent. This obviates the need to use a correction factor for the fluorescence of form I DNA when measuring the amount of this form relative to the amounts of unstrained forms in agarose gels. In the case of …

Fragment Multiplicity Dependent Charge Distributions In Heavy Ion Collisions, M. B. Tsang, C. Williams, M. J. Huang, W. G. Lynch, L. Phair, D. R. Bowman, J. Dinius, C. K. Gelbke, D. O. Handzy, W. C. Hsi, G. J. Kunde, M. A. Lisa, Graham F. Peaslee, A. Botvina, M-C. Lemaire, S. R. Souza, G. Van Buren, R. J. Charity, L. G. Sobotka, C. Schwarz, U. Lynen, J. Pochodzalla, H. Sann, W. Trautmann, D. Fox, R. T. De Souza, N. Carlin

Faculty Publications

The dependence of intermediate-mass-fragment (IMF) element distributions on the multiplicity, NIMF, of detected fragments has been measured for 84Kr+197Au collisions at E/A=35, 55, 70, 100, 200, and 400 MeV. The observed dependence can be parametrized as P(NIMF|Z)∝P(Z)exp(-c⋅NIMF⋅Z), where c is a beam-energy and excitation-energy dependent parameter. Previous work indicated this parameter is zero in the liquid-gas coexistence region and positive in the gaseous phase. In contrast, we observe both negative and positive values for c, revealing the meaning of this parameter to be less straightforward than previously assumed. The magnitude of c appears nonetheless to provide a nontrivial test of …

Conformations And Relative Stabilities Of The Cis And Trans Isomers In A Series Of Isolated N-Phenylamides, V. P. Manea, K. J. Wilson, John R. Cable

Chemistry Faculty Publications

The gas-phase conformations of a series of isolated N-phenylamides have been determined from vibrationally resolved electronic spectra obtained by resonant two-photon ionization in a supersonic jet expansion. Both the cis and trans isomers of formanilide were identified, with the cis isomer in 6.5% abundance. The spectral features displayed by this isomer are consistent with a nonplanar geometry which undergoes a large change in the phenyl torsional angle following electronic excitation. The more abundant trans isomer of formanilide adopts a planar structure and is stabilized by 2.5 kcal/mol with respect to the cis isomer. In the excited electronic state the relative …

Oxidized Sterols In Patients With Diabetic Heart Disease And Microwave-Mediated Stereoselective Synthesis Of 3-Keto Cholesterol And Cholesterol Epoxide, Cholesteryl Ester Epoxides, Meenakashi N. Kothavale

Theses

Oxidized low density lipoproteins (ox-LDL) may play important role in mediating hypercholesterolemic endothelial dysfunction. The uptake of modified LDL by macrophages to form foam cells has been implicated in the enhancement of atherosclerosis. Recent reports have suggested that when LDL undergoes oxidation in vitro , it is accompanied by a substantial loss of free and esterified cholesterol leading to the formation of oxidation products of cholesterol ( oxysterols). These compounds are present in human atherosclerotic plaques and in human foam cells.

In this regard we have recently studied the plasma sterol composition in diabetic heart patients We have found cholesterol …

Catalytic Control Of Nitric Oxide With Gaseous Or Solid Reducing Materials, Xiaoyong Tang

Theses

Air pollution from mobile sources is an increasingly serious problem throughout most of the industrialized would. Diesel powered vehicles, because of their higher thermal efficiency, tend to emit less carbon monoxide and unburned hydrocarbons than gasoline vehicles, but emit significant quantities of NO_x. Therefore, it is essential to develop improved emission control equipment in diesel engines. A fixed bed catalytic reactor was used to study the decomposition of NO and the reduction of NO to N₂ by different reductants that can be found in diesel exhaust, such as hydrocarbons, CO and elemental carbon over different catalysts. The …

Chiral Separation Of Monoterpenes Using Mixtures Of Sulfated Β-Cyclodextrins And Α-Cyclodextrin As Chiral Additives In The Reversed-Polarity Capillary Electrophoresis Mode, Kyung Hyun Gahm, Lisa W. Chang, Daniel W. Armstrong

Chemistry Faculty Research & Creative Works

The use of mixtures of sulfated β-cyclodextrins and native α-cyclodextrin as chiral additives in capillary electrophoresis was evaluated for the chiral resolution of neutral, cyclic and bicyclic monoterpenes, including α-pinene, (β-pinene, camphene and limonene. Binding properties of sulfated β-cyclodextrins towards these monoterpenes were studied. It was found that there was no enantioresolution of these terpenoids over the concentration range studied. However, the addition of α-cyclodextrin to the running electrolyte in addition to 6.5 mM sulfated β-cyclodextrins, imparted differences in the mobilities of the terpenoid enantiomers and resulted in remarkable enantiomeric separations of α-pinene (R(s)=25), β-pinene (R(s)=12), camphene (R(s)=12) and limonene …

Nucleotide Or Nucleoside Photoaffinity Compound Modified Antibodies, Methods For Their Manufacture And Use Thereof As Diagnostics And Therapeutics, Boyd E. Haley, Heinz Köhler, Krishnan Rajagopalan, Gabriela Pavlinkova

Chemistry Faculty Patents

Sites on antibodies having affinity for photoaffinity compounds, in particular purine or azidopurine containing compounds are taught. These sites provide for the site-specific attachment of nucleotide photoaffinity compounds to antibodies, e.g., ATP- or GTP-analog photoaffinity compounds by photochemical reaction. These nucleotide photoaffinity compounds may additionally be attached to molecules having a desired therapeutic or diagnostic activity, and the resultant conjugates used as diagnostics or therapeutics.

Enhancing The Performance Of Membrane Introduction Mass Spectrometry By Organic Carrier And Liquid Chromatographic Separation, Shi Ouyang, Yong Hong Chen, Yan Xu

Chemistry Faculty Publications

A method of membrane introduction mass spectrometry with liquid chromatographic separation (LC/MIMS) for the analysis of volatile organic compounds (VOCs) in water has been developed. The method not only inherited all the advantages of membrane introduction mass spectrometry by flow-injection analysis (FIA/MIMS), but also expanded the application of MIMS to the determination of compounds with identical quantitation ions. Because the quantitation by LC/MIMS is based on two-dimensional identification (retention time (tr) and mass-to-charge ratio ()), it provides a tangible approach to the analysis of VOCs in complex aqueous samples. In this work, a C18 column and a mobile phase (methanol/water) …

The Voltammetry Of Sc3@C82, Mark Anderson, Harry Dorn, Paul Burbank, Steven Stevenson, James Gibson

Mark R. Anderson

Many endohedral metallofullerenes have a C82 cage surrounding the metals, even though the normal arc-vaporization method of fullerene preparation does not generate C82 in significant abundance.1-10Manolopous et al.11-13attribute the low abundance of empty-cage C82 to the unfavorable electron configuration of this species. Consequently, the prevalence of C82 in metallofullerenes may be the result of an electron transfer from the encapsulated metal atoms to the fullerene cage.10-13 The extent of this charge transfer also contributes to the properties (e.g. catalytic, superconductive, nonlinear optical, and ferromagnetic) that are attributed to the endohedral metallofullerenes.14,15Because of the importance of the charge transfer reaction, characterization …

Synthetic Strategies For The Construction Of Enantiomeric Azanoradamantanes, Daniel Becker, Roger Nosal, Daniel L. Zabrowski, Daniel Flynn

Chemistry: Faculty Publications and Other Works

The amino azanoradamantane hexahydro-2,5b-methano-IH-3aS,3aa,6aa-cyclopenta-[clpyrrole-4a-amine 1and the corresponding enantiomer ent-1 have been prepared along with benzamide derivatives SC-52491and SC-52490, respectively, which are of pharmaceutical interest. The key meso-azabicyclo[3.3.0] intermediate 3 was prepared via three separate routes: a [3+2] cycloaddition route, a radical cyclization/ionic cyclization route, and a reductive Pauson-Khand route.

Molecular Dynamics Of Crosslinked And Normal Hemoglobins, Liang Zhao

Master's Theses

No abstract provided.

Development Of Crosslinking Reagents, And Intra- And Intermolecular Multi-Linking Hemoglobin Molecules As Potential Blood Substitutes, Yaguo Zheng

Dissertations

No abstract provided.

Multinuclear Magnetic Resonance Studies Of Anion Binding To Copper, Zinc-Superoxide Dismutase, And Of Lithium Transport And Binding In Cultured Neuroblastoma Cells, Cherian Zachariah

Dissertations

No abstract provided.

Ionic Interaction Studies Of Bovine Copper, Zinc-Superoxide Dismutase, Hanan A. Hasan

Dissertations

No abstract provided.

The Computational Study Of "Model" Pollutants In Clay Montmorillonite, Sung-Ho Park

Dissertations

No abstract provided.

Ph And Osmolality Effects On Lipid-Enhanced Sickle And Normahemoglobin Oxidation, Sharron Kay Jenkins

Dissertations

No abstract provided.

Molecular Engineering Of Side-Chain Liquid Crystalline Polymers By Living Polymerizations, Coleen Pugh, Alan L. Kiste

Chemistry and Biochemistry

“Living” anionic, cationic, metalloporphyrin and ring-opening metathesis polymerizations have been used to prepare well-defined side-chain liquid crystalline homopolymers, block and graft copolymers and statistical copolymers. This paper analyzes their successes and failures by reviewing the mechanistic aspects and experimental conditions of each type of polymerization, and identifies other classes of mesogenic monomers that could be polymerized in a controlled manner in the future. The emerging structure/property relationships are then identified using well-defined SCLCPs in which only one structural feature is varied while all others remain constant.

The thermal transitions of liquid crystalline polymethacrylates, polynorbomenes and poly(viny1 ether)s reach their limiting …

Identification Of The Adp-L-Glycero-D-Manno-Heptose-6-Epimerase (Rfad) And Heptosyltransferase Ii (Rfaf) Biosynthesis Genes From Nontypeable Haemophilus Influenzae 2019, W A. Nichols, B W. Gibson, William Melaugh, N G. Lee, M Sunshine, M A. Apicella

Chemistry Faculty Publications

Haemophilus influenzae is an important human pathogen. The lipooligosaccharide (LOS) of H. influenzae has been implicated as a virulence determinant. To better understand the assembly of LOS in nontypeable H. influenzae (NtHi), we have cloned and characterized the rfaD and rfaF genes of NtHi 2019, which encode the ADP-L-glycero-D-manno-heptose-6-epimerase and heptosyltransferase II enzymes, respectively. This cloning was accomplished by the complementation of Salmonella typhimurium lipopolysaccharide (LPS) biosynthesis gene mutants. These deep rough mutants are novobiocin susceptible until complemented with the appropriate gene. In this manner, we are able to use novobiocin resistance to select for specific NtHi LOS inner core …

Characterization Of A Transposon Tn916-Generated Mutant Of Haemophilus Ducreyi 35000 Defective In Lipooligosaccharide Biosynthesis, B W. Gibson, A A. Campagnari, William Melaugh, M A. Apicella, S Grass, Jing Wang, Katherine L. Palmer, R S. Munson

Chemistry Faculty Publications

To define the role of the surface lipooligosaccharide (LOS) of Haemophilus ducreyi in the pathogenesis of chancroid, Tn916 mutants of H. ducreyi 35000 defective in expression of the murine monoclonal antibody (MAb) 3F11 epitope on H. ducreyi LOS were identified by immunologic screening. One mutant, designated 1381, has an LOS which lacks the MAb 3F11 epitope and migrates with an increased mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The gene disrupted by the Tn916 element in strain 1381 was identified by cloning the sequences flanking the Tn916 element. The sequences were then used to probe a lambda DASHII genomic library. …

Novel Palladium (Ii) Catalysts For Asymmetric Synthesis, Arab El-Qisairi

Dissertations

No abstract provided.

Competition Between Li+ And Mg2+ For Human Rbcmembrane Phospholipids And Guanine Nucleotide Binding Proteins, Chandra Srinivasan

Dissertations

No abstract provided.

Sodium Nitrite Alone Protects The Brain O _I_ Microsomal Ca -Atpase Against Potassium Cyanide-Induced Neurotoxicity In Rats, Odutayo O. Odunuge, G.. A. Adenuga

Faculty Publications

The effect of a short-term oral administration of potassium cyanide (KCN) (200 ppm in diet) with or without sodium nitrite (NaNO2) pretreatment on rat brain microsomal Ca2* ATPase was investigated. The specific activity value of the enzyme significantly decreased (p<0.05) by 50% compared with control and by 63% for KCN-treated rats compared with KCN-treated rats pretreated with NaNO;,. There was no significant difference at the h = 0.05 level between the values obtained for the control and KCN-treated rats pretreated with NaNO,. These results show both that feeding lowers brain microsomal Ca2f-ATPase activity and that NaNO, has a protective role (antidote function) in that respect.

Pseudo-Steady States In The Model Of The Bray-Liebhafsky Oscillatory Reaction, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.

The S0 State Of The Oxygen-Evolving Complex In Photosystem Ii Is Paramagnetic:  Detection Of An Epr Multiline Signal, Johannes Messinger, John H. Robblee, Edward Yu, Kenneth Sauer, Vittal K. Yachandra, Melvin P. Klein

Edward Yu

The photosynthetic oxidation of water to molecular oxygen is energetically driven by light-induced charge separations in the reaction center of photosystem II (PS II). The reaction is catalyzed by a tetranuclear manganese cluster contained in the oxygen-evolving complex (OEC). The OEC cycles through five different redox states termed S0 to S4, with S1 being the darkstable state. Oxygen is released during the S4 f S0 transition.1 The removal of one electron from the OEC on each S state transition leads to the idea that alternate S states should be paramagnetic because of their odd-electron number. The multiline EPR signal, which …

An Approach To A Generalized Synthesis For 2-Halo-1,1-Diarylalkenes, Cheryll R. Roberts

Theses, Dissertations and Capstones

This study was concerned with the development of a generalized synthesis of halogenated 1,1-diarylalkenes. The alkylation of 1,1-diphenylethylene was carried out by the addition of organolithium compounds (C Li, PhLi, t-BuLi, n-BuLi). N-bromo-succinimide (NBS) was used for bromination. The reaction forming triphenylbromo-ethylene gave the largest percent yield (93.6%). The reaction forming 2-bromo-3,3- dimethyl-l,l-dipheny1-1-butene resulted in a 38.1% yield. Each product structure was confirmed by proton and carbon-13 nuclear magnetic resonance, and infrared spectroscopy.

Determination Of Selected Hydrocarbon Concentrations In Reformate Using Near Infrared Spectroscopy, Roy Roger Bledsoe Jr.

Theses, Dissertations and Capstones

Near infrared spectroscopy was used as a quantitative technique employing multiple linear regression and partial least squares regression for determining the concentration of hydrocarbon groups and individual hydrocarbons present in reformate, a refinery process stream. Models were generated for total aromatics, benzene, toluene, total xylenes and individual xylene isomers, ethylbenzene, total paraffins, n-hexane, n-heptane, total isoparaffins, isopentane, 2-methylhexane, total naphthenes, methylcyclopentane, and total olefins. Some models are being used with an on-line instrument to constantly monitor a reformate stream as it leaves the reforming unit, with a standard error of performance of 0.118 volume percent for the prediction …