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2002

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Articles 301 - 330 of 429

Full-Text Articles in Chemistry

Radio Frequency-Induced Plasma Polymerization Of Allyl Alcohol And 1-Propanol, Şennur Candan Jan 2002

Radio Frequency-Induced Plasma Polymerization Of Allyl Alcohol And 1-Propanol, Şennur Candan

Turkish Journal of Chemistry

The effect of the composite parameters' plasma power (P)-to-monomer flow rate (\phi) ratio (P/\phi) in the plasma polymerization of allyl alcohol and 1-propanol was studied. The radio-frequency plasmas of deposits operated at low power (1-15 W) were investigated using deposition rate measurements. Detailed chemical information on the plasma polymers was obtained by X-ray photoelectron spectroscopy (XPS). The study of the surface chemistry of films created from allyl alcohol and 1-propanol demonstrates the importance of the double bond for good \underline{C}-O group retention. The deposition rates of both plasma polymers were found to increase with increasing P. The comparison of the …

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Bifunctional Allyl-Sulphonium Salt As A Novel Addition--Fragmentation Agent For Photoinitiated Cationic Polymerization, Utku Küçüktömbeki̇ci̇, Mustafa Deği̇rmenci̇, Yusuf Yağci Jan 2002

Bifunctional Allyl-Sulphonium Salt As A Novel Addition--Fragmentation Agent For Photoinitiated Cationic Polymerization, Utku Küçüktömbeki̇ci̇, Mustafa Deği̇rmenci̇, Yusuf Yağci

Turkish Journal of Chemistry

Bifunctional allyl tetrahydrothiophenium hexafluoroantimonate was synthesized via a one-pot reaction of 3-chloro-2-chloromethylpropene with thiophene in the presence of sodium hexafluoroantimonate. The initiation capability of this salt, in conjunction with a photochemical free radical source such as 2,2-dimethoxy-2-phenyl acetophenone and benzophenone, via an addition-fragmentation mechanism in the cationic polymerization of cyclohexene oxide and butyl vinyl ether is investigated.

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Synthesis And Characterization Of Some 3-Alkyl-4-Amino-5-Cyanomethyl-4h-1,2,4-Triazoles, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Kemal Sancak Jan 2002

Synthesis And Characterization Of Some 3-Alkyl-4-Amino-5-Cyanomethyl-4h-1,2,4-Triazoles, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Kemal Sancak

Turkish Journal of Chemistry

The preparation and characterization of some 3-alkyl-4-amino-5-cyanomethyl-4H-1,2,4-triazoles with active methylene groups are described and their structural properties using NMR and IR spectra and elemental analyses are given.

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Conformational Analysis Of Pol-Rfamide Ii (Glu}^{1}-Trp^{2}-Leu^{3}-Lys^{4}-Gly^{5}-Arg^{6}-Phe^{7}-Nh_{2}) Heptapeptide, Lütfü Demi̇r, Niftali Mihrali Godjaev Jan 2002

Conformational Analysis Of Pol-Rfamide Ii (Glu}^{1}-Trp^{2}-Leu^{3}-Lys^{4}-Gly^{5}-Arg^{6}-Phe^{7}-Nh_{2}) Heptapeptide, Lütfü Demi̇r, Niftali Mihrali Godjaev

Turkish Journal of Chemistry

The geometrical structure of the sea anemone and sea pansies neuropeptide Pol-RFamide II Glu^{1}-Trp^{2}-Leu^{3}-Lys^{4}-Gly^{5}-Arg^{6}-Phe^{7}-NH_{2} was carried out by molecular mechanics (MM). The linkage bonds are characterised by the torsional angles \phi, \psi and \omega and the side groups characterised by the torsional angles \chi_{1}, \chi_{2}, \chi_{3},... subsequently. The energy-map for each monopeptide of the Pol-RFamide II was drawn in the range of -180° to 180° with increments of 20°. Conformation facilities for monopeptides were decided from these maps. These results were used in the analysis of the dipeptide Glu^{1}-Trp^{2}. Then, the Glu^{1}-Trp^{2}-Leu^{3} tripeptide was examined by using the calculated results …

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The Protonation Constants Of Some Aliphatic Alkylamines In Ethanol-Water Mixtures, Esma Kiliç, Gülteki̇n Gökçe, Esi̇n Canel Jan 2002

The Protonation Constants Of Some Aliphatic Alkylamines In Ethanol-Water Mixtures, Esma Kiliç, Gülteki̇n Gökçe, Esi̇n Canel

Turkish Journal of Chemistry

Protonation constants of methyl-, ethyl-, propyl- and butylamines Were determined potentiometrically using an electrode system calibrated in concentration units of hydrogen ion in ethanol-water mixtures (10\% -80\% ethanol, v/v) at an ionic strength of 0.1 and at 25°C. The trend in the values of protonation constants of these aliphatic amines was explained in terms of the number of alkyl groups and solvent composition. The basicity orders were found to be NH_{3} < R_{3}N < RNH_{2} < R_{2}NH (R:-CH_{3}, -C_{2}H_{5}, -n-C_{3}H_{7} and --n-C_{4}H_{9}) in all the solvent mixtures studied.

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Dna Biosensor For Microcystis Spp. Sequence Detection By Using Methylene Blue And Ruthenium Complex As Electrochemical Hybridization Labels, Arzum Erdem, Kagan Kerman, Burcu Meri̇ç, Di̇lşat Özkan, Pinar Kara, Mehmet Özsöz Jan 2002

Dna Biosensor For Microcystis Spp. Sequence Detection By Using Methylene Blue And Ruthenium Complex As Electrochemical Hybridization Labels, Arzum Erdem, Kagan Kerman, Burcu Meri̇ç, Di̇lşat Özkan, Pinar Kara, Mehmet Özsöz

Turkish Journal of Chemistry

An electrochemical biosensor for the voltammetric detection of DNA sequences related to the bloom-forming genera of cyanobacteria, Microcystis spp., is described. A specific DNA ``probe'' is designed based on sequence polymorphism within the 16S ribosomal DNA (rDNA) of the Microcystis spp. These single-stranded probes were immobilized onto carbon paste electrode (CPE) with the adsorption at a controlled potential. The probes were hybridized with the complementary ``target'' sequences at the electrode. The formed hybrids on the electrode surface were evaluated by differential pulse voltammetry (DPV) and cyclic voltammetry (CV) using methylene blue (MB) and tris (2,2' -- bipyridine) ruthenium (II) chloride …

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Modeling Of Taqi Endonuclease Purification By Hplc, Mehmet Düzenli̇, Kutlu Ö. Ülgen Jan 2002

Modeling Of Taqi Endonuclease Purification By Hplc, Mehmet Düzenli̇, Kutlu Ö. Ülgen

Turkish Journal of Chemistry

The present work is based on the previously reported purification study of TaqI endonuclease^{5} and aimed to simulate the experimentally obtained chromatograms in order to reduce the time and cost in the design, optimization and scaling up of purification processes. Three different models depending on equilibrium, rate and plate theories are used in the mathematical description of experimental elution profiles and the solutions of the model equations are compared. The equilibrium-dispersive theory provides excellent results in predicting the experimental chromatograms. It is thus recognized that band dispersion takes place in the column through axial dispersion and nonequilibrium effects. The user-friendly …

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Synthesis And Spectral Characterization Of Unsymmetric Organotin(Iv) Derivatives, Sadiq-Ur Rehman, Saqib Ali, Moazzam H. Ghatti, Khadija Shahid, M. Mazhar, M. Kaleem, Amin Badshah Jan 2002

Synthesis And Spectral Characterization Of Unsymmetric Organotin(Iv) Derivatives, Sadiq-Ur Rehman, Saqib Ali, Moazzam H. Ghatti, Khadija Shahid, M. Mazhar, M. Kaleem, Amin Badshah

Turkish Journal of Chemistry

Unsymmetric Organotin(IV) compounds of general formula R_{4-n}SnR^\prime_{n} have been synthesized by the reaction of corresponding organotin(IV) chlorides with n-hexyl magnesium bromide prepared in dry ether in situ, where R = CH_{3}, n-C_{4}H_{9}, C_{6}H_{5}, C_{6}H_{5}CH_{2} and R^\prime = n-C_{6}H_{13}. The reactions were carried out in dry toluene, refluxed for 6 h and the final products were purified through vacuum distillation. These compounds were characterized by multinuclear NMR (^{1}H, ^{13}C, ^{119}Sn), IR spectroscopy and mass spectrometry to predict their structures. All spectroscopic results support the four-coordination and tetrahedral geometry of the compounds.

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Bromination Of Benzonorbornadiene Using A Mixture Of Sodium Bromide And Sodium Perborate At High Temperatures, Erdal Şenocak, Yavuz Taşkesenli̇gi̇l, Ferhan Tümer Jan 2002

Bromination Of Benzonorbornadiene Using A Mixture Of Sodium Bromide And Sodium Perborate At High Temperatures, Erdal Şenocak, Yavuz Taşkesenli̇gi̇l, Ferhan Tümer

Turkish Journal of Chemistry

Bromination of benzonorbornadiene (1) with sodium bromide in the presence of sodium perborate at room temperature gave only one product, the dibromide 2 produced via Wagner-Meerwein rearrangement. However, at high temperatures, bromination resulted predominantly in the formation of rearranged solvolytic products whose formation mechanisms are discussed.

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Atomic And Molecular Electron Affinities: Photoelectron Experiments And Theoretical Computations, Jonathan C. Rienstra-Kiracofe, Gregory S. Tschumper, Henry F. Schaefer, Sreela Nandi, G. Barney Ellison Jan 2002

Atomic And Molecular Electron Affinities: Photoelectron Experiments And Theoretical Computations, Jonathan C. Rienstra-Kiracofe, Gregory S. Tschumper, Henry F. Schaefer, Sreela Nandi, G. Barney Ellison

Chemistry Faculty Research & Creative Works

A review is given of the experimental determination of electron affinities (EAs). Also considered is the ability of computational chemistry methods to predict electron affinities. The development and present status of computational chemistry techniques for the prediction of atomic molecular EAs is also reviewed in a historical context. Through comparisons to experimental EAs and results from other theoretical methods, analysis of DFT EAs is given. In the context of other theoretical methods, the successes and failures of DFT EA predictions are detailed.

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Reproduction In West Virginia Populations Of The Southern Two-Lined Salamander (Eurycea Cirrigera), Timothy R. Brophy, Thomas K. Pauley Jan 2002

Reproduction In West Virginia Populations Of The Southern Two-Lined Salamander (Eurycea Cirrigera), Timothy R. Brophy, Thomas K. Pauley

Faculty Publications and Presentations

We describe reproduction in West Virginia populations of the southern two-lined salamander (Eurycea cirrigera) and provide insights into the behavioral ecology of this wide-ranging urodele. The first signs of reproduction are evident well before the arrival of Spring. Sexually mature adults inhabit the cold, rocky streams of southwestern West Virginia in early February. Females arc known by the presence of large oocytes visible through the body wall and males by their extremely swollen heads. Breeding occurs in the stream during late March and is marked by the presence of gravid females with sperm caps in their posterior cloacae. Eggs are …

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Effect Of Oxygen Vacancies On The Magnetic Structure Of The La₀.₆Sr₀.₄Feo3-Δ Perovskite: A Neutron Diffraction Study, Zili Chu, William B. Yelon, Jinbo Yang, William Joseph James, Harlan U. Anderson, Yixiang Xie, Satish K. Malik Jan 2002

Effect Of Oxygen Vacancies On The Magnetic Structure Of The La₀.₆Sr₀.₄Feo3-Δ Perovskite: A Neutron Diffraction Study, Zili Chu, William B. Yelon, Jinbo Yang, William Joseph James, Harlan U. Anderson, Yixiang Xie, Satish K. Malik

Physics Faculty Research & Creative Works

Magnetic interactions in perovskite compounds of the type La1-xSrxMO3-δ (M=3d transition such as Mn and Fe) are presumed to arise through a super exchange between 3d electrons of the magnetic ions via oxygen orbitals. The magnetic structure of La0.6Sr0.4FeO3-δ has been studied with neutron diffraction. Oxygen vacancies were created by annealing samples under various gases including N2, air and mixtures of CO/CO2. All La0.6Sr0.4FeO3-δ compounds maintain the rhombohedral structure (space group R3̄c). The air- or oxygen-annealed samples have almost no oxygen …

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Electrical And Magnetotransport Properties Of Canted Antiferromagnet Dy₅Si₂Ge₂, R. Nirmala, V. Sankaranarayanan, K. Sethupathi, Zili Chu, William B. Yelon, V. Prasad, A. V. Morozkin, Satish K. Malik, S. V. Subramanyam Jan 2002

Electrical And Magnetotransport Properties Of Canted Antiferromagnet Dy₅Si₂Ge₂, R. Nirmala, V. Sankaranarayanan, K. Sethupathi, Zili Chu, William B. Yelon, V. Prasad, A. V. Morozkin, Satish K. Malik, S. V. Subramanyam

Physics Faculty Research & Creative Works

Summary form only given. Since the giant magnetocaloric effect is encountered in a ferromagnetic Gd5Si2Ge2 alloy near room temperature it is considered as a suitable material for magnetic refrigerator applications. Also a commensurate structural transition occurs at the magnetic transition temperature and there is a good correlation between the crystal structure and magnetic properties. Such observations have triggered numerous experimental studies on similar rare earth alloys and compounds. We have synthesized its Dy- analogue, namely, Dy5Si2Ge2 and have characterized it by means of room temperature X-ray diffraction, ac magnetic susceptibility (15 K - 300 K), electrical resistivity (at zero field …

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Bromination Of 2,3-Dibromobenzobarrelene At Different Conditions: Highly Brominated Benzobicyclic Systems, Ari̇f Daştan Jan 2002

Bromination Of 2,3-Dibromobenzobarrelene At Different Conditions: Highly Brominated Benzobicyclic Systems, Ari̇f Daştan

Turkish Journal of Chemistry

The electrophilic addition of bromine to 2,3-dibromobenzobarrelene at 10^oC led to the formation of completely rearranged products in high yield. Bromination of 2,3-dibromobenzobarrelene with molecular bromine in decalin at 150^oC and with DBTCE in CCl_{4} at 77^oC gave rearranged and non-rearranged products. The radical and ionic mechanism are discussed. All compounds were characterized properly, by NMR spectroscopy and chemical transformation.

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Synthesis And Magnetic, Spectral And Thermal Studies On Metal 1,3,8,10,15,17,22,24-Octanitrophthalocyanines, Kallam R. Venugopala Reddy, Jathi Keshavayya Jan 2002

Synthesis And Magnetic, Spectral And Thermal Studies On Metal 1,3,8,10,15,17,22,24-Octanitrophthalocyanines, Kallam R. Venugopala Reddy, Jathi Keshavayya

Turkish Journal of Chemistry

A simple and novel method for the preparation of 1,3,8,10,15,17,22,24-octanitrophthalocyanine derivatives, MPcON's (M = Fe (III)Cl, Zn(II), Co(II), Cu(II) and Ni(II)), was developed. The dark green complexes were characterized by elemental analysis, electronic spectra, IR spectra, thermogravimetry, differential thermal analysis, powder X-ray diffraction and magnetic susceptibility.

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Synthesis Of Novel Acidic Mono Azo Dyes And An Investigation Of Their Use In The Textile Industry, Emel Yildiz, Hami̇t Boztepe Jan 2002

Synthesis Of Novel Acidic Mono Azo Dyes And An Investigation Of Their Use In The Textile Industry, Emel Yildiz, Hami̇t Boztepe

Turkish Journal of Chemistry

1,2-hydroxo phenyl azo,8-amino naphthalene, 3,6-disulfonic acid Mono sodium salt (HFANS) and its metal complex with chromium (III) salt (ligand metal ratio 1:1) were synthesized as H-acid derivatives. Having an acidic character these dyes are used for dyeing polyamide and protein fibers. Their properties such as dyeing, wash fastness and color classification were investigated according to international standard methods.

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Combinatorial Chemistry: A Guide For Librarians, Philip Barnett Jan 2002

Combinatorial Chemistry: A Guide For Librarians, Philip Barnett

Publications and Research

No abstract provided.

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Applications Of Bismuth(Iii) Compounds In Organic Synthesis, Ram Mohan, Nicholas Leonard, Laura Wieland Jan 2002

Applications Of Bismuth(Iii) Compounds In Organic Synthesis, Ram Mohan, Nicholas Leonard, Laura Wieland

Scholarship

No abstract provided.

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Bismuth Triflate Catalyzed Allylation Of Acetals: A Simple And Mild Method For Synthesis Of Homoallyl Ethers, Ram Mohan, Laura Wieland, Herbert Zerth Jan 2002

Bismuth Triflate Catalyzed Allylation Of Acetals: A Simple And Mild Method For Synthesis Of Homoallyl Ethers, Ram Mohan, Laura Wieland, Herbert Zerth

Scholarship

The allylation of acetals using allyltrimethylsilane is efficiently catalyzed by bismuth triflate (1.0 mol%). The reaction proceeds smoothly at room temperature to afford the corresponding homoallyl ether in good yield. The mild reaction conditions, the low toxicity of bismuth salts, and the high catalytic efficiency of the system make this procedure particularly attractive for large-scale synthesis.

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Induction Of Myocarditis And Valvuluitis In Lewis Rats By Different Epitopes Of Cardiac Myosin And Its Implications In Rheumatic Carditis, Jeffrey E. Galvin, Mark E. Hemric, Stanley D. Konsanke, Stephen M. Factor, Anthony Quinn, Madeleine W. Cunningham Jan 2002

Induction Of Myocarditis And Valvuluitis In Lewis Rats By Different Epitopes Of Cardiac Myosin And Its Implications In Rheumatic Carditis, Jeffrey E. Galvin, Mark E. Hemric, Stanley D. Konsanke, Stephen M. Factor, Anthony Quinn, Madeleine W. Cunningham

Faculty Publications and Presentations

Immune responses against cardiac myosin and group A streptococcal M protein have been implicated in the pathogenesis of rheumatic heart disease. Although cardiac myosin is known to produce myocarditis in susceptible animals, it has never been investigated for its role in production of valvular heart disease, the most serious sequelae of group A streptococcal infection in acute rheumatic fever. In our study, cardiac myosin induced valvulitis in the Lewis rat, and epitopes responsible for production of valvulitis were located in the rod region. Human and rat cardiac myosins induced severe myocarditis in the Lewis rats as expected. A purified S2 …

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Effect Of Polymer-Surface Mobility On Adhesion In Poly(Methyl Methacrylate)-Tape System, Bhavesh C. Gandhi, Frank D. Blum, Lokeswarappa R. Dharani Jan 2002

Effect Of Polymer-Surface Mobility On Adhesion In Poly(Methyl Methacrylate)-Tape System, Bhavesh C. Gandhi, Frank D. Blum, Lokeswarappa R. Dharani

Chemistry Faculty Research & Creative Works

The interaction between two polymer layers, especially adhesion between them, plays an important role in polymer processing and other applications. Detailed knowledge of the molecular structure and dynamics of polymer interfaces, and how they relate to macroscopic mechanical properties, should help designers construct more functional systems. Unfortunately, there have been few studies where both molecular and macroscopic studies have been performed on similar systems. In previous studies from our group, we have probed the dynamics of poly(methyl acrylate) (PMA) and thermal behavior of poly(methyl methacrylate) (PMMA) on silica. These studies helped us paint a picture for strongly bound molecules on …

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Purification Of The Hmg1 Protein And Investigation Of Its Interactions With Diepoxide Cross-Linked Dna, Gayle Pageau Jan 2002

Purification Of The Hmg1 Protein And Investigation Of Its Interactions With Diepoxide Cross-Linked Dna, Gayle Pageau

Honors Theses

HMG1 is a nonhistone chromosomal protein that binds preferentially to some types of globally modified DNA. HMG1 has been implicated in the cellular response to the anti-cancer agent cisplatin, functioning to block excision repair of specific distorted platinated DNA lesions and resulting in enhanced cytotoxicity. We have investigated whether other DNA-binding agents also produce lesions that are recognized by HMG1. Specifically, we used polyacrylamide gel shift assays to monitor the potential HMG1 binding of diepoxybutane interstrand cross-links, which have been suggested to induce DNA bending. We isolated the native protein from chicken erythrocytes and expressed engineered HMG domain proteins in …

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Motion Based Event Recognition Using Hmm, Gu Xu, Yu-Fei Ma, Hong-Jiang Zhang, Shiqiang Yang Jan 2002

Motion Based Event Recognition Using Hmm, Gu Xu, Yu-Fei Ma, Hong-Jiang Zhang, Shiqiang Yang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Motion is an important cue for video understanding and is widely used in many semantic video analyses. We present a new motion representation scheme in which motion in a video is represented by the responses of frames to a set of motion filters. Each of these filters is designed to be most responsive to a type of dominant motion. Then we employ hidden Markov models (HMMs) to characterize the motion patterns based on these features and thus classify basketball video into 16 events. The evaluation by human satisfaction rate to classification result is 75%, demonstrating effectiveness of the proposed approach …

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Parameters Affecting Partitioning Of 6 Pcb Congeners In Natural Sediments, Eid A. Alkhatib, Carl Weigand Jan 2002

Parameters Affecting Partitioning Of 6 Pcb Congeners In Natural Sediments, Eid A. Alkhatib, Carl Weigand

Chemistry & Physics Faculty Publications

Polychlorinated biphenyls (PCBs) released by bottom sediments were determined by experiments in which the sediments were artificially resuspended using sediment contaminated with PCBs in a particle entrainment simulator (PES). Sediment cores, spiked with PCBs, were collected from the Housatonic River in Connecticut and run in the PES at simulated shear stresses from 0 to 0.6 N m(-2). Experimental results from these simulations have shown that mean concentration of PCBs in the solid phase for sites with high volatile organic carbon (VOC) were significantly greater than samples with low VOC; the reverse was true for the water phase. In addition, on …

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Thermogravimetric Studies Of Pmma On Silica, Bing Zhang, Frank D. Blum Jan 2002

Thermogravimetric Studies Of Pmma On Silica, Bing Zhang, Frank D. Blum

Chemistry Faculty Research & Creative Works

The thermal degradation of poly(methyl methacrylate) (PMMA) has been studied extensively. It is well accepted that the degradation process is a radical chain reaction involving initiation, depropagation, transfer, and termination reactions. In the degradation process, the factors having observable effects on the decomposition behavior include molecular mass, polydispersity, tacticity, and sample dimensions. The effects of tacticity on the degradation behavior of PMMA were investigated by Kashiwagi et al., Jellinek et al. And Chiamtore et al. The results indicated that both isotactic and syndiotactic PMMA have similar decomposition pathways and activation energies. Isotactic PMMA will decompose at a slightly lower temperature …

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Synthetic, Structural, Magnetic, And Mössbauer Spectral Study Of {Fe[Hc(3,5-Me2pz)3]2}I2 And Its Spin-State Crossover Behavior, Daniel L. Reger, Christine A. Little, Mark D. Smith, Arnold L. Rheingold, Kin Chung Lam, Thomas L. Concolino, Gary J. Long, Raphaël P. Hermann, Fernande Grandjean Jan 2002

Synthetic, Structural, Magnetic, And Mössbauer Spectral Study Of {Fe[Hc(3,5-Me2pz)3]2}I2 And Its Spin-State Crossover Behavior, Daniel L. Reger, Christine A. Little, Mark D. Smith, Arnold L. Rheingold, Kin Chung Lam, Thomas L. Concolino, Gary J. Long, Raphaël P. Hermann, Fernande Grandjean

Chemistry Faculty Research & Creative Works

The complex {Fe [HC(3,5-Me2pz)3]2} I2 (1) has been prepared from the reaction of FeI2 and HC(3,5-Me2pz)3 (pz = pyrazolyl ring) in a 1:2 ratio. The complex is high spin in both the solid state and in solution at ambient temperature. In the solid state, magnetic susceptibility and Mössbauer spectral studies indicate that samples of the complex that have been crystallized and dried change completely from high-spin to low-spin upon cooling below 195 K, with a substantial two-step thermal hysteresis in the transition. The spin-crossover properties of 1 are sample …

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Site-Specific Modification Of De Novo Designed Coiled-Coil Polypeptides With Inorganic Redox Complexes, Anna Fedorova, Michael Y. Ogawa Jan 2002

Site-Specific Modification Of De Novo Designed Coiled-Coil Polypeptides With Inorganic Redox Complexes, Anna Fedorova, Michael Y. Ogawa

Chemistry Faculty Publications

A stepwise procedure for preparing of site-specific binuclear metallopeptides is described. The modification procedure involves the alkylation of a cysteine side chain by reaction with [Ru(bpy)(2)(phen-ClA)](2+), where bpy = 2,2'-bipyridine and phen-ClA = 5-chloroacetaniido-1,10-phenanthroline, followed by the coordination of a ruthenium pentammine complex to a histidine residue located elsewhere along the sequence. The apo and metalated versions of the peptides C10H21(30-mer) and H10C21(30-mer) display circular dichroism spectra having minima at 208 and 222 nm, with theta(222)/theta(208) = 1.04 to indicate that these peptides exist as a-helical coiled-coils in aqueous solution. When the ruthenium polypyridyl complex is attached to C10H21(30-mer), the …

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Determination Of The Micropore Structures Of Activated Carbons By Adsorption Of Various Dyestuffs From Aqueous Solution, Fuat Güzel, İlhan Uzun Jan 2002

Determination Of The Micropore Structures Of Activated Carbons By Adsorption Of Various Dyestuffs From Aqueous Solution, Fuat Güzel, İlhan Uzun

Turkish Journal of Chemistry

In this study, some activated carbons prepared from sour cherry pits under various conditions were investigated. For comparison purposes, the commercial activated carbons Merck-2514 and Merck-2184 were used. The nitrogen adsorption isotherms at 77 K were used as reference for comparison, while p-nitrophenol, methylene blue, orange-II and victoria blue adsorptions were determined from aqueous solution at 298 K. It was clear from the specific surface area values obtained that the best activated carbon was obtained by activation for 4 hours following the chemical activation. Its adsorption properties are closer to the levels of the Merck commercial carbons. It was concluded …

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A Conformational Exploration Of Dissymmetric Macrolides Antibiotics, Salah Belaidi, A. Dibi, M. Omari Jan 2002

A Conformational Exploration Of Dissymmetric Macrolides Antibiotics, Salah Belaidi, A. Dibi, M. Omari

Turkish Journal of Chemistry

Conformational analysis of the macrolides from 12 to 22 links was carried out using molecular mechanics. Calculations indicate that each studied macrocycle presents eight families of preferential conformers. They result from the combination of the conformations of the two systems diene and \alpha ,\beta -unsaturated ester. Among these conformers three families (F5, F6 and F3) have the lowest energy. The two families F5 and F6 adopt an s-cis conformation of the ester function and s-trans of the diene system with a pseudo-parallel arrangement of the two systems for the first family and a pseudo-antiparallel for the second. The third family …

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The Ligase Detection Reaction: The Evolution Of A Mutation Detection Strategy, Hannah D. Farquar Jan 2002

The Ligase Detection Reaction: The Evolution Of A Mutation Detection Strategy, Hannah D. Farquar

LSU Doctoral Dissertations

Early detection of genetic mutations is important for control of diseases such as cancer and Alzheimer's. Early detection requires methods that detect small amounts of mutated DNA in very large amounts of normal or wild type DNA. One method to detect mutated DNA is the ligase detection reaction (LDR). Since its inception LDR has evolved greatly from a simple detection reaction after PCR amplification to PCR/RE/LDR, a scheme which uses nucleoside base analogs in PCR to convert wild type sequences to sequences containing restriction endonuclease (RE) sites which can then be cleaved leaving only mutant sequences for detection by LDR. …

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