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2013

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Articles 18721 - 18750 of 20110

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Design, Construction And Load Testing Of The Pat Daly Road Bridge In Washington County, Mo, With Internal Glass Fiber Reinforced Polymers Reinforcement, Zhibin Lin, Mostafa Fakharifar, Chenglin Wu, Genda Chen, Wesley James Bevans, Arun Vijay Kumar Gunasekaran, Sahra Sedigh Jan 2013

Design, Construction And Load Testing Of The Pat Daly Road Bridge In Washington County, Mo, With Internal Glass Fiber Reinforced Polymers Reinforcement, Zhibin Lin, Mostafa Fakharifar, Chenglin Wu, Genda Chen, Wesley James Bevans, Arun Vijay Kumar Gunasekaran, Sahra Sedigh

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The overarching goal of this project is to deploy and assess an innovative corrosion-free bridge construction technology for long-term performance of new and existing bridges. The research objective of this project is to conduct a comprehensive study (instrumentation, construction, both laboratory and field evaluation) of a rapidly constructed and durable, three-span bridge with cast-in-place cladding steel reinforced concrete substructure and precast concrete decks/girders reinforced with glass fiber reinforced polymers (GFRP). The bridge has one conventional concrete-girder span, one conventional steel-girder span, and one innovative concrete box-girder span. The conventional concrete and steel girders were used to demonstrate the effective use …

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Ivory Tower Graduates In The Red: The Role Of Debt In Higher Education, Nicholas D. Hartlep, Lucille Eckrich Jan 2013

Ivory Tower Graduates In The Red: The Role Of Debt In Higher Education, Nicholas D. Hartlep, Lucille Eckrich

Faculty Publications - College of Education

No abstract provided.

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Meta-For, Vincent Mario Pignatiello Ii Jan 2013

Meta-For, Vincent Mario Pignatiello Ii

Antioch University Dissertations & Theses

A clinician is entrusted with the difficult task of organizing, integrating, and formulating a vast amount of information provided by a patient in order to conduct therapy. Typically, a theoretical paradigm is employed in this endeavor. This paper constructs a theory of theoretical paradigms—a meta-theory—to understand better how clinicians organize and understand patient information. The theory of theory posits that theoretical paradigms function as complex metaphors developed within a culture. The argument presented here utilizes research from various areas of psychology—including those focusing on cognitive research, psycholinguistics, and philosophy of theory—to develop the meta-theory. The central thesis of this research …

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Existential Concerns Of Individuals Living With Chronic Mental Illness In Guam, Christina Maria B. Dela Cruz Jan 2013

Existential Concerns Of Individuals Living With Chronic Mental Illness In Guam, Christina Maria B. Dela Cruz

Antioch University Dissertations & Theses

Individuals living with chronic mental illness experience a host of challenges associated with the symptoms of their illness. In an effort to help restore healthy functioning, mental health treatment for individuals with chronic mental illness thus focuses primarily on symptom reduction and management. Recent research exploring the lived experience of individuals with chronic mental illness suggests that apart from their symptoms, these individuals also encounter existential issues related to the self, relationships with others, temporality, making meaning out of the illness experience, and managing life with the illness. At the same time, however, this research has tended to focus on …

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Applying A Leadership Framework To Historically Black Colleges And Universities (Hbcus) Post Fordice, Armenta Hinton Jan 2013

Applying A Leadership Framework To Historically Black Colleges And Universities (Hbcus) Post Fordice, Armenta Hinton

Antioch University Dissertations & Theses

Historically Black Colleges and Universities (HBCUs) have a list of outstanding accomplishments that span over a century; however, this segment of higher education continues to be underfunded and remains in a position of justifying its existence in a postracial America. The issues facing HBCUs are significant. Race-based legislation has created a dual system of American higher education that adversely affects these minority serving institutions, impacting the quality of education they dispense and producing potentially negative effects on vulnerable and under-served collegians. Supreme Court Justice Thomas’s opinion in the U.S. v. Fordice (1992) case opposed the creation of HBCUs as “enclaves …

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A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur Jan 2013

A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur

Antioch University Dissertations & Theses

This study investigated a terrestrial climate proxy, phytoliths, as a complimentary approach to documenting the dynamics of present and past vegetation on Sanak Island, the largest island in a small island group in the eastern Aleutian archipelago, and as a new basis by which to interpret Holocene environmental variability in Alaska. A phytolith reference collection was established from 59 selected plant species of maritime tundra belonging to 27 families. The grass species and a sedge species produced abundant phytolith forms whereas the majority of dicotyledons in this study were trace producers of phytoliths. A paleoenvironmental reconstruction from fossil phytoliths recovered …

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Edison State College General Catalog 2012-2013, Edison State College Jan 2013

Edison State College General Catalog 2012-2013, Edison State College

FSW Course Catalogs

Edison State College General Catalog Volume Fifty One. 2012-2013. Scanned by Internet Archive.

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An Experiment To Assess The Utilization Of Adaptive Control Technology On A Cnc Lathe To Reduce Energy Consumption During Machining: A Step Towards Environmentally Conscious Manufacturing, Dean L. Bartles Jan 2013

An Experiment To Assess The Utilization Of Adaptive Control Technology On A Cnc Lathe To Reduce Energy Consumption During Machining: A Step Towards Environmentally Conscious Manufacturing, Dean L. Bartles

All-Inclusive List of Electronic Theses and Dissertations

Global warming is a well-documented concern. If left unabated, many scientists believe that global warming could potentially have devastating impacts to life on earth. Current research points to greenhouse gas emissions caused by the burning of fossil fuels to produce electricity as one of the primary causes of global warming. The more electricity produced and consumed the more greenhouse gas emissions are released to the atmosphere. Industry is one of the most significant consumers of electricity. Within industry, manufacturing accounts for a significant majority of all energy consumed with machine tools being one of the largest consumers. Machine tool builders …

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Mathematics Career Simulations: An Invitation, Robb Sinn, Marnie Phipps Jan 2013

Mathematics Career Simulations: An Invitation, Robb Sinn, Marnie Phipps

International Journal for the Scholarship of Teaching & Learning

A simulated academic career was combined with inquiry-based learning in an upper-division undergraduate mathematics course. Concepts such as tenure, professional conferences and journals were simulated. Simulation procedures were combined with student-led, inquiry-based classroom formats. A qualitative analysis (ethnography) describes the culture that emerged within the simulation during a pilot test. A discussion follows evaluating the potential for career simulations to invite students to consider graduate studies and academic careers in the STEM disciplines.

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2013 Web Features, Office Of Communications & Marketing, Morehead State University. Jan 2013

2013 Web Features, Office Of Communications & Marketing, Morehead State University.

Morehead State Press Release Archive, 1961 to the Present

Web features for 2013.

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Women In Science 2013, Clark Science Center's Summer Research Fellows Program Jan 2013

Women In Science 2013, Clark Science Center's Summer Research Fellows Program

SURF Abstracts (Women in Science)

“Women in Science” summarizes research done by Smith College’s Summer Research Fellowship (SURF) Program participants. Ever since its 1967 start, SURF has been a cornerstone of Smith’s science education. In 2013, 167 students participated in SURF, supervised by 57 faculty mentor-advisors drawn from the Clark Science Center’s fourteen science, mathematics, and engineering departments and programs, and associated centers and units. At summer’s end, SURF participants were asked to summarize their research experiences for this publication.

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Bacterial Colonization And Extinction On Marine Aggregates: Stochastic Model Of Species Presence And Abundance, Andrew M. Kramer, M. Maille Lyons, Fred C. Dobbs, John M. Drake Jan 2013

Bacterial Colonization And Extinction On Marine Aggregates: Stochastic Model Of Species Presence And Abundance, Andrew M. Kramer, M. Maille Lyons, Fred C. Dobbs, John M. Drake

OES Faculty Publications

Organic aggregates provide a favorable habitat for aquatic microbes, are efficiently filtered by shellfish, and may play a major role in the dynamics of aquatic pathogens. Quantifying this role requires understanding how pathogen abundance in the water and aggregate size interact to determine the presence and abundance of pathogen cells on individual aggregates. We build upon current understanding of the dynamics of bacteria and bacterial grazers on aggregates to develop a model for the dynamics of a bacterial pathogen species. The model accounts for the importance of stochasticity and the balance between colonization and extinction. Simulation results suggest that while …

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Intercalibraton In Chemical Oceanography-- Getting The Right Number, Gregory A. Cutter Jan 2013

Intercalibraton In Chemical Oceanography-- Getting The Right Number, Gregory A. Cutter

OES Faculty Publications

Intercalibration has a strict metrological definition, but in brief, it's an open sharing of methods and results between laboratories to achieve the most accurate data with the fewest random and systematic errors. In the field of chemical oceanography where concentrations of many constituents can be in the nano- to picomolar range, the salt water matrix can be difficult to analyze, and knowing the exact concentrations, or even chemical forms, of biologically required elements is essential, intercalibration is a very relevant and needed tool. Implementing it is not simple because errors can occur at any step in the process of taking …

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Surface Production Fuels Deep Heterotrophic Respiration In Northern Peatlands, J. Elizabeth Corbett, David J. Burdige, Malak M. Tfaily, Angela R. Dial, William T. Cooper, Paul H. Glaser, Jeffrey P. Chanton Jan 2013

Surface Production Fuels Deep Heterotrophic Respiration In Northern Peatlands, J. Elizabeth Corbett, David J. Burdige, Malak M. Tfaily, Angela R. Dial, William T. Cooper, Paul H. Glaser, Jeffrey P. Chanton

OES Faculty Publications

Multiple analyses of dissolved organic carbon (DOC) from pore waters were conducted to define the processes that govern carbon balance in peatlands: (1) source, reactivity, and transport of DOC with respect to vegetation, peat, and age of carbon substrate, (2) reactivity of DOC with respect to molecular size, and (3) lability to photoxidation of surficial DOC. We found that surface organic production fuels heterotrophic respiration at depth in advection-dominated peatlands, especially in fens. Fen DOC was Δ14Cenriched relative to the surrounding fen peat, and fen respiration products were similar to this enriched DOC indicating that DOC was the …

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Using Ammonium Pore Water Profiles To Assess Stoichiometry Of Deep Remineralization Processes In Methanogenic Continental Margin Sediments, David J. Burdige, Tomoko Komada Jan 2013

Using Ammonium Pore Water Profiles To Assess Stoichiometry Of Deep Remineralization Processes In Methanogenic Continental Margin Sediments, David J. Burdige, Tomoko Komada

OES Faculty Publications

In many continental margin Sediments, a deep reaction zone exists which is separated from remineralization processes near the sediment surface. Here, methane diffuses upward to a depth where it is oxidized by downwardly diffusing sulfate. However, the methane sources that drive this anaerobic oxidation of methane (AOM) in the sulfate-methane transition zone (SMT) may vary among sites. In particular, these sources can be thought of as either (i) "internal" sources from in situ methanogenesis (regardless of where it occurs in the sediment column) that are ultimately coupled to organic matter deposition and burial, or (ii) "external" sources such as hydrocarbon …

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Adsorption Equilibrium Of Water Vapor On Activated Carbon And Alumina And Carbon And Alumina Impregnated With Hygroscopic Salt, Ioan Solomon, Ana Mafalda Ribeiro, Joao Carlos Santos, Jose Miguel Loureiro, Alirio E. Rodrigues, Ion Sandu, Ioan Mamaliga Jan 2013

Adsorption Equilibrium Of Water Vapor On Activated Carbon And Alumina And Carbon And Alumina Impregnated With Hygroscopic Salt, Ioan Solomon, Ana Mafalda Ribeiro, Joao Carlos Santos, Jose Miguel Loureiro, Alirio E. Rodrigues, Ion Sandu, Ioan Mamaliga

Turkish Journal of Chemistry

The adsorption equilibrium of water vapor on different adsorbent materials has been studied. Small grains of commercial activated carbon and alumina, with a diameter of d_g = 1.5 \times 10^{-3} m, were impregnated with a hygroscopic salt (calcium chloride) to improve the performance of these materials. The main characteristics of the new composite materials were obtained by adsorption/desorption of nitrogen at 77 K and salt distribution on the adsorbent surface was shown using scanning electron microscopy. The adsorption equilibrium isotherms of water vapor were measured by a gravimetric system at 2 different temperatures in the case of alumina and impregnated …

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A Two-Component Protocol For Synthesis Of 3-(2-(Substituted Phenylamino)Thiazol-4-Yl)-2h-Chromen-2-Ones, Aamer Saeed, Mubeen Arif, Madiha Irfan, Michael Bolte Jan 2013

A Two-Component Protocol For Synthesis Of 3-(2-(Substituted Phenylamino)Thiazol-4-Yl)-2h-Chromen-2-Ones, Aamer Saeed, Mubeen Arif, Madiha Irfan, Michael Bolte

Turkish Journal of Chemistry

An efficient 2-component synthesis of a series of 3-(2-(substituted phenylamino)thiazol-4-yl)-2H-chromen-2-ones (3a--j) was achieved by the reaction of 3-(2-thiocyanatoacetyl)-2H-chromen-2-one (1) with a variety of suitably substituted anilines in 1:1 molar ratio in ethanol. The structures of the products were established by elemental analyses, and UV-vis, FTIR, ^1H and ^{13}C NMR, and mass spectroscopy. 3-(2-(4-Methylphenylamino)thiazol-4-yl)-2H-chromen-2-one (3j) was further characterized by single crystal X-ray diffraction study. This compound, C_{19}H_{14}N_2OS, crystallizes in the orthorhombic space group Pna21, with Z = 4, and unit cell parameters a = 13.0785(11), b = 25.746(2), c = 4.7235(3) Å, \alpha = \beta = \gamma = 90°.

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Asymmetric Synthesis Of \Alpha-(Heteroaryl)Alkylamines And \Alpha -Amino Acids Via Nucleophilic 1,2-Addition Of Lithiated Heterocycles To Aldehyde Samp-Hydrazones, Dieter Enders, Giuseppe Del Signore, Gerhard Raabe Jan 2013

Asymmetric Synthesis Of \Alpha-(Heteroaryl)Alkylamines And \Alpha -Amino Acids Via Nucleophilic 1,2-Addition Of Lithiated Heterocycles To Aldehyde Samp-Hydrazones, Dieter Enders, Giuseppe Del Signore, Gerhard Raabe

Turkish Journal of Chemistry

The asymmetric synthesis of \alpha-(heteroaryl)alkylamines was accomplished by employing a diastereoselective nucleophilic 1,2-addition of lithiated aromatic heterocycles to aldehyde SAMP-hydrazones, followed by BH_3 . THF or SmI_2 promoted removal of the chiral auxiliary. The CBz or benzoyl-protected amines were obtained in good yields (40\%--78\%) and excellent enantiomeric excesses (ee = 88\%--99\%). The methodology can be applied to the synthesis of highly enantioenriched \alpha-amino acids (ee = 90\%--99\%).

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An Expedient Synthesis Of 6-Vinylfulvene, İhsan Erden, Jenny Sabol, Ana Gubeladze, Andrea Ruiz Jan 2013

An Expedient Synthesis Of 6-Vinylfulvene, İhsan Erden, Jenny Sabol, Ana Gubeladze, Andrea Ruiz

Turkish Journal of Chemistry

6-Vinylfulvenes constitute a class of fulvenes that are difficult to access due to the lack of a general method for their synthesis. In particular, the unsubstituted parent system has been very difficult to obtain by existing methods. In this communication we describe a convenient 3-step protocol for the synthesis of the title compound by way of sulfide oxidation and subsequent sulfoxide elimination.

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Dft Study Of Tautomerism In Aklavinone, Burhan Lemi̇ Türker Jan 2013

Dft Study Of Tautomerism In Aklavinone, Burhan Lemi̇ Türker

Turkish Journal of Chemistry

Aklavinone has an anthraquinone-based chromophore and its backbone highly resembles the kernel of some anthracycline antibiotics that possess anticancer activity, e.g., daunomycin. Since aklavinone's structure possesses many --OH groups and 2 keto groups, it is quite probable that certain tautomeric equilibria may occur. Presently, aklavinone prototropic tautomers possessing embedded anthraquinone moiety have been investigated quantum chemically by using density functional theory at the levels of RB3LYP/6-31G(d) and RB3LYP/6-31G(d,p). Additionally, IR spectra of the tautomers were calculated. Moreover, the phenolate ions obtained from the most stable tautomer in water were considered, and the protonation of this tautomer at various possible sites …

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Umpolung Strategy: Advances In Catalytic C-C Bond Formations, Serkan Eymur, Mehmet Göllü, Ci̇hangi̇r Tanyeli̇ Jan 2013

Umpolung Strategy: Advances In Catalytic C-C Bond Formations, Serkan Eymur, Mehmet Göllü, Ci̇hangi̇r Tanyeli̇

Turkish Journal of Chemistry

This mini-review examines the recent advances in umpolung strategy, devised originally by Corey and Seebach. Although numerous stoichiometric variants have been published to date, this article covers just the catalytic C-C bond forming reactions due to their major benefits such as atom economy, less pollution, and workable simplicity. In the context of umpolung, the studies are evaluated under 3 main titles: enzyme, N-heterocyclic carbene, and cyanide ion catalyzed reactions. In particular, enzyme and NHC catalyzed reactions mainly involve asymmetric applications.

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An Amphipathic Thioxanthone-Anthracene Photoinitiator For Free-Radical Polymerization, Deni̇z Tunç Beyazit, Burçi̇n Gacal, Yusuf Yağci Jan 2013

An Amphipathic Thioxanthone-Anthracene Photoinitiator For Free-Radical Polymerization, Deni̇z Tunç Beyazit, Burçi̇n Gacal, Yusuf Yağci

Turkish Journal of Chemistry

A novel thioxanthone-anthracene (TX-A) photoinitiator possessing an octyl group, TX-A-Oct, as amphipathic photoinitiator was synthesized by click chemistry. Its ability to initiate photopolymerization of various monomers, namely methyl methacrylate (MMA), acryl amide (Am), butyl acrylate (BA), styrene (St), and a multifunctional monomer trimethylolpropane triacrylate (TMPTA), was examined in both the presence and absence of air. TX-A-Oct was found to be effective in initiating polymerization also in the absence of a co-initiator. UV, FTIR, and fluorescence spectroscopic analysis and polymerization studies revealed that depending on the conditions photoinitiations occur through both anthracene and thioxanthone chromophoric groups by hydrogen abstraction and endoperoxide …

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Calixarene-Based Receptors For Molecular Recognition, Mustafa Yilmaz, Serkan Erdemi̇r Jan 2013

Calixarene-Based Receptors For Molecular Recognition, Mustafa Yilmaz, Serkan Erdemi̇r

Turkish Journal of Chemistry

Calixarene-based molecular receptors have been a widely developing area in material science and technology for the last few decades. Due to their bowl-shaped geometry, calixarene macrocycles are used as hosts allowing organic and inorganic guests to coordinate/sorb onto their cavity. This work briefly reviews the recent development of calixarenes.

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Optimization Of A Gas Chromatography--Mass Spectrometry Method Using Chemometric Techniques For The Determination Of Ezetimibe In Human Plasma, Ebru Uçaktürk, Nuran Özaltin Jan 2013

Optimization Of A Gas Chromatography--Mass Spectrometry Method Using Chemometric Techniques For The Determination Of Ezetimibe In Human Plasma, Ebru Uçaktürk, Nuran Özaltin

Turkish Journal of Chemistry

A new, rapid, and sensitive gas chromatography--mass spectrometry (GC-MS) method was developed for the determination of ezetimibe (EZE) in human plasma. EZE was derivatized prior to GC-MS analysis. Various derivatization techniques such as acetylation, methylation, and silylation were tried. EZE was extracted from plasma with high recovery (94.39%--97.57%) using methyl tertbutyl ether and carbonate buffer (pH 9). Chromatographic conditions were optimized using chemometric methods. In the first step, optimization with factorial design, chromatographic variables (initial and final column temperature, oven ramp rate, and flow rate of gas) were screened to select important variables for the retention of EZE. In the …

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Synthesis And Biological Activities Of Methylenebis-4h-1,2,4-Triazole Derivatives, Yildiz Uygun, Hacer Bayrak, Havva Özkan Jan 2013

Synthesis And Biological Activities Of Methylenebis-4h-1,2,4-Triazole Derivatives, Yildiz Uygun, Hacer Bayrak, Havva Özkan

Turkish Journal of Chemistry

5,5'-Methylenebis(4--phenyl-4H-1,2,4-triazole-3-thiol) (2) was synthesized starting from hydrazinecarbothioamide compound (1). Treatment of compound 2 with ethyl bromoacetate produced diethyl 5,5'-{methylenebis[(4-phenyl-4H-1,2,4-triazole-5,3-diyl)thio]}diacetate (3), which was converted to the corresponding diacetohydrazide derivative (4) by treatment with hydrazine hydrate. The reaction of compound 4 with several aldehydes produced the corresponding arylidene hydrazides, 5a--d. Syntheses of Mannich bases 6a--c were carried out by the treatment of compound 2 with several amines in the presence of formaldehyde. (4{[5-({5-[(4-Amino-2-chlorophenyl)thio]-4-phenyl-4H-1,2,4-triazol-3-ylmethyl)-4-phenyl-4H-1,2,4-triazol-3-yl]thio}-3-chlorophenyl)amine (8) was prepared by reduction of 2 nitro groups of 3,3' -methylenebis{5-[(2-chloro-4-nitrophenyl)thio]-4-phenyl-4H-1,2,4-triazole} (7) that were obtained from the condensation of 2} with 3,4-dichloronitrobenzene. The newly synthesized compounds were screened …

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Synthesis, Spectroscopic Characterization, And Biological Screening Of Binuclear Transition Metal Complexes Of Bicompartmental Schiff Bases Containing Indole And Resorcinol Moieties, Mahendra Raj Karekal, Mruthyunjayaswamy Bennikallu Hire Mathada Jan 2013

Synthesis, Spectroscopic Characterization, And Biological Screening Of Binuclear Transition Metal Complexes Of Bicompartmental Schiff Bases Containing Indole And Resorcinol Moieties, Mahendra Raj Karekal, Mruthyunjayaswamy Bennikallu Hire Mathada

Turkish Journal of Chemistry

A series of binucleating Cu(II), Ni(II), and Zn(II) complexes of bicompartmental ligands with ONO donors were prepared. The ligands were synthesized by the condensation of 5-substituted-3-phenyl-1H-indole-2-carboxyhydrazides and 4,6-diacetylresorcinol. The newly synthesized ligands and their complexes were characterized by elemental analysis and various spectral studies like IR, ^1H NMR, ESI-mass, UV-Vis, ESR, thermal studies, magnetic susceptibility, molar conductance, and powder-XRD data. All the complexes were binuclear and monomeric in nature. Cu(II) complexes have octahedral geometry, whereas Ni(II) and Zn(II) complexes have square planar and tetrahedral geometry, respectively. The redox property of the Cu(II) complex was investigated by electrochemical method using cyclic …

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Determination Of Zineb In Tap Water And Tomato Samples By Adsorptive Catalytic Stripping Voltammetry, Özlem Karakoç, Nuri̇ Naki̇boğlu Jan 2013

Determination Of Zineb In Tap Water And Tomato Samples By Adsorptive Catalytic Stripping Voltammetry, Özlem Karakoç, Nuri̇ Naki̇boğlu

Turkish Journal of Chemistry

This paper describes a sensitive and accurate adsorptive catalytic stripping voltammetric method for the determination of zineb (zinc ethylene-bis- dithiocarbamate) in tap water and tomato samples. The method is based on the reduction of adsorbed zineb at a hanging mercury drop electrode following its catalytic oxidation using peroxydisulfate as an oxidizing reagent. Chemical and instrumental parameters of the process were optimized. The catalytic mechanism of the reduction of zineb is discussed as well. The limits of detection (3 s) and quantification (10 s) and linear range of the method for accumulation time of 60 s were calculated as 8.1 nM, …

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A New Anthracene Derivative Of Calix[4]Arene As A Fluorescent Chemosensor, Özlem Şahi̇n, Mustafa Şahi̇n, Nuri̇ye Koçak, Mustafa Yilmaz Jan 2013

A New Anthracene Derivative Of Calix[4]Arene As A Fluorescent Chemosensor, Özlem Şahi̇n, Mustafa Şahi̇n, Nuri̇ye Koçak, Mustafa Yilmaz

Turkish Journal of Chemistry

A new anthracene derivative of calix[4]arene was synthesized as a highly fluorescent compound. This compound was examined for its fluorescent properties towards different metal ions (Li^+, Na^+, Mg^{2+}, Ca^{2+}, Ba^{2+}, Ni^{2+}, Cu^{2+}, Zn^{2+}, Pb^{2+}) by UV and fluorescence spectroscopy. On complexation by alkaline earth metal cations and transition metal cations, the fluorescence spectrum was quenched. In particular, Ca^{2+} caused greater than 98% quenching of the anthracene derivative of calix[4]arene.

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A Kinetic Study Of Atom Transfer Radical Polymerization Of Styrene With Bis(2-Pyridyl)Ethylenedimethanimine Derivative Ligands, Hülya Arslan, Yasemi̇n Küçük, Ayfer Menteş, Meti̇n Hayri̇ Acar Jan 2013

A Kinetic Study Of Atom Transfer Radical Polymerization Of Styrene With Bis(2-Pyridyl)Ethylenedimethanimine Derivative Ligands, Hülya Arslan, Yasemi̇n Küçük, Ayfer Menteş, Meti̇n Hayri̇ Acar

Turkish Journal of Chemistry

Atom transfer radical polymerization (ATRP) of styrene was carried out with multidentate nitrogen-based ligands, namely N,N'-bis[phenyl(pyrid-2-yl)methylene] ethane-1,2-diamine (BPDA) and N,N'-bis[methyl(pyrid-2-yl)methylene] ethane-1,2-diamine (BMDA), and catalyst systems at catalyst/ligand molar ratios of 1/0.33, 1/0.5, 1/1, and 1/1.5 by using 2 different initiators, (1-bromoethyl)benzene (BEB) and ethyl-2-bromopropionate (EBP). Linear first-order kinetic plots were observed for ATRP of styrene upon using BPDA as a ligand with both initiators. Even though the linear slopes indicate that radical concentration remains constant during reactions, high molecular weights were obtained at low conversion and showed a linear relation thereafter. To investigate the molecular weight effect, reactions were also …

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Biodegradability Of Degradable Mulching Film In A Laboratory-Controlled Composting Test, Xuemei Zhang, Yaxi Huang, Deqiang Li, Zicheng Wen, Baoxun Sui, Zhiyong Liu Jan 2013

Biodegradability Of Degradable Mulching Film In A Laboratory-Controlled Composting Test, Xuemei Zhang, Yaxi Huang, Deqiang Li, Zicheng Wen, Baoxun Sui, Zhiyong Liu

Turkish Journal of Chemistry

A series of degradable films was prepared, and 2 formulas of polyethylene (PE) films with the highest degradable performance were experimentally determined. These films contained 3.43% and 0.44% stearate, and were denoted as PE-3 and PE-4, respectively. Their biodegradability was studied in a laboratory-controlled composting test using ordinary PE film (OPEF) as a control. Contrast composting experiments indicated that the biodegradability of untreated samples was very low, and that the biodegradation rates of PE films after natural aging were significantly higher. FT-IR analysis showed that OPEF changed little after the composting experiment, and that PE-3 and PE-4 showed a carbonyl …

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