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2017

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Articles 10741 - 10770 of 12443

Full-Text Articles in Physical Sciences and Mathematics

Enzymatically Active Microspheres For Self-Propelled Colloidal Engines, Jungeun Park Jan 2017

Enzymatically Active Microspheres For Self-Propelled Colloidal Engines, Jungeun Park

Dissertations and Theses

Micro- and nano-motors have attracted numerous attentions from various scientific areas due to their potential applications. Most studies on self-propelled colloidal engines have exploited catalytic decomposition of hydrogen peroxide to drive the motor. Since the hydrogen peroxide is caustic, it is not suitable to use in biological applications, encouraging people to develop “greener” fuels. The aim of this research is to study a new transduction mechanism for self-propulsion not tied to hydrogen peroxide, and which can in particular be used with biological molecules as fuels. In this study, we focus on making particles with enzymatic activity which can effectively decompose …

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Fukushima Daiichi-Derived Radionuclides In The Ocean: Transport, Fate, And Impacts, Ken O. Buesseler, Minhan Dai, Michio Aoyama, Claudia R. Benítez-Nelson,, Sabine S. Charmasson, Kathryn A. Higley, Vladimir S. Maderich, Pere Masqué, Paul J. Morris, Deborah H. Oughton, John N. Smith Jan 2017

Fukushima Daiichi-Derived Radionuclides In The Ocean: Transport, Fate, And Impacts, Ken O. Buesseler, Minhan Dai, Michio Aoyama, Claudia R. Benítez-Nelson,, Sabine S. Charmasson, Kathryn A. Higley, Vladimir S. Maderich, Pere Masqué, Paul J. Morris, Deborah H. Oughton, John N. Smith

Research outputs 2014 to 2021

The events that followed the Tohoku earthquake and tsunami on March 11, 2011, included the loss of power and overheating at the Fukushima Daiichi nuclear power plants, which led to extensive releases of radioactive gases, volatiles, and liquids, particularly to the coastal ocean. The fate of these radionuclides depends in large part on their oceanic geochemistry, physical processes, and biological uptake. Whereas radioactivity on land can be resampled and its distribution mapped, releases to the marine environment are harder to characterize owing to variability in ocean currents and the general challenges of sampling at sea. Five years later, it is …

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Pso Algorithm For An Optimal Power Controller In A Microgrid, Waleed Al-Saedi, Stefan Lachowicz, Daryoush Habibi, Octavian Bass Jan 2017

Pso Algorithm For An Optimal Power Controller In A Microgrid, Waleed Al-Saedi, Stefan Lachowicz, Daryoush Habibi, Octavian Bass

Research outputs 2014 to 2021

This paper presents the Particle Swarm Optimization (PSO) algorithm to improve the quality of the power supply in a microgrid. This algorithm is proposed for a real-time selftuning method that used in a power controller for an inverter based Distributed Generation (DG) unit. In such system, the voltage and frequency are the main control objectives, particularly when the microgrid is islanded or during load change. In this work, the PSO algorithm is implemented to find the optimal controller parameters to satisfy the control objectives. The results show high performance of the applied PSO algorithm of regulating the microgrid voltage and …

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A Synergistic Approach For Evaluating Climate Model Output For Ecological Applications, Rochelle Cavanaugh, Ej Murphy, Et Al, Walker O. Smith Jr., Et Al Jan 2017

A Synergistic Approach For Evaluating Climate Model Output For Ecological Applications, Rochelle Cavanaugh, Ej Murphy, Et Al, Walker O. Smith Jr., Et Al

VIMS Articles

Increasing concern about the impacts of climate change on ecosystems is prompting ecologists and ecosystem managers to seek reliable projections of physical drivers of change. The use of global climate models in ecology is growing, although drawing ecologically meaningful conclusions can be problematic. The expertise required to access and interpret output from climate and earth system models is hampering progress in utilizing them most effectively to determine the wider implications of climate change. To address this issue, we present a joint approach between climate scientists and ecologists that explores key challenges and opportunities for progress. As an exemplar, our focus …

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Interactive Effects Of Elevated Temperature And Co2 On Nitrate, Urea, And Dissolved Inorganic Carbon Uptake By A Coastal California, Usa, Microbial Community, Jl Spackeen, Rachel E. Sipler, K Xu, Et Al, Da Bronk Jan 2017

Interactive Effects Of Elevated Temperature And Co2 On Nitrate, Urea, And Dissolved Inorganic Carbon Uptake By A Coastal California, Usa, Microbial Community, Jl Spackeen, Rachel E. Sipler, K Xu, Et Al, Da Bronk

VIMS Articles

Average global temperatures and carbon dioxide (CO2) levels are expected to increase in the coming decades. Implications for ocean ecosystems include shifts in microbial community structure and subsequent modifications to nutrient pathways. Studying how predicted future temperature and CO2 conditions will impact the biogeochemistry of the ocean is important because of the ocean’s role in regulating global climate. We determined how elevated temperature and CO2 affect uptake rates of nitrate, urea, and dissolved inorganic carbon (DIC) by 2 size classes (0.7-5.0 and >5.0 µm) of a microbial assemblage collected from coastal California, USA. This microbial community was incubated for 10 …

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Unification Of Gravity And Quantum Theory, Adam Daniels Jan 2017

Unification Of Gravity And Quantum Theory, Adam Daniels

Faculty-Sponsored Student Research & Capstones

An overview of the four fundamental forces of physics as described by the Standard Model (SM) and prevalent unifying theories beyond it is provided. Background knowledge of the particles governing the fundamental forces is provided, as it will be useful in understanding the way in which the unification efforts of particle physics has evolved, either from the SM, or apart from it. It is shown that efforts to provide a quantum theory of gravity have allowed supersymmetry (SUSY) and M-Theory to become two of the prevailing theories for unifying gravity with the remaining non-gravitational forces.

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Semiconductor Photocatalysis: Mechanisms, Photocatalytic Performances And Lifetime Of Redox Carriers, Ruixin Zhou Jan 2017

Semiconductor Photocatalysis: Mechanisms, Photocatalytic Performances And Lifetime Of Redox Carriers, Ruixin Zhou

Theses and Dissertations--Chemistry

Photocatalytic reactions mediated by semiconductors such as ZnS, TiO2, ZnO, etc. can harvest solar energy into chemical bonds, a process with important prebiotic and environmental chemistry applications. The recycling of CO2 into organic molecules (e.g., formate, methane, and methanol) facilitated by irradiated semiconductors such as colloidal ZnS nanoparticles has been demonstrated. ZnS can also drive prebiotic reactions from the reductive tricarboxylic acid (rTCA) cycle such as the reduction of fumarate to succinate. However, the mechanism of photoreduction by ZnS of the previous reaction has not been understood. Thus, this thesis reports the mechanisms for heterogeneous photocatalytic reductions …

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Edge Colorings Of K(M,N) With M+N-1 Colors Which Forbid Rainbow Cycles, Peter Johnson, Claire Zhang Jan 2017

Edge Colorings Of K(M,N) With M+N-1 Colors Which Forbid Rainbow Cycles, Peter Johnson, Claire Zhang

Theory and Applications of Graphs

For positive integers m, n, the greatest number of colors that can appear in an edge coloring of K(m,n) which avoids rainbow cycles is m + n - 1. Here these colorings are constructively characterized. It turns out that these colorings can be encoded by certain vertex labelings of full binary trees with m + n leafs.

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A Statistical Analytical Model For Hydrophilic Electropore Characterization: A Comparison Study, P. Marracino, M. Liberti, P.T. Vernier, F. Apollonio Jan 2017

A Statistical Analytical Model For Hydrophilic Electropore Characterization: A Comparison Study, P. Marracino, M. Liberti, P.T. Vernier, F. Apollonio

Bioelectrics Publications

Molecular dynamics (MD) simulations have proved to be a useful tool for unveiling many aspects of pore formation in lipid membranes under the influence of external electric fields. In order to compare the size-related properties of pores in bilayers of various compositions, generated and maintained under different physical and chemical conditions, reference metrics are needed for characterizing pore geometry and its evolution over time. In the present paper three different methodologies for evaluating electropore geometrical behavior will be compared: (i) the first allows analysis of the dimensions of the pore through an algorithm that uses a Monte Carlo simulated annealing …

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Homeomorphic Tetrahedralization Of Multi-Material Images With Quality And Fidelity Guarantees, Jing Xu, Andrey N. Chernikov Jan 2017

Homeomorphic Tetrahedralization Of Multi-Material Images With Quality And Fidelity Guarantees, Jing Xu, Andrey N. Chernikov

Computer Science Faculty Publications

We present a novel algorithm for generating three-dimensional unstructured tetrahedral meshes of multi-material images. The algorithm produces meshes with high quality since it provides a guaranteed dihedral angle bound of up to 19.47° for the output tetrahedra. In addition, it allows for user-specified guaranteed bounds on the two-sided Hausdorff distance between the boundaries of the mesh and the boundaries of the materials. Moreover, the mesh boundary is proved to be homeomorphic to the object surface. The algorithm is fast and robust, it produces a sufficiently small number of mesh elements that comply with these guarantees, as compared to other software. …

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Accounting For Locational, Temporal, And Physical Similarity Of Residential Sales In Mass Appraisal Modeling: The Development And Application Of Geographically, Temporally, And Characteristically Weighted Regression, Paul E. Bidanset, Michael Mccord, John R. Lombard, Peadar Davis, William J. Mccluskey Jan 2017

Accounting For Locational, Temporal, And Physical Similarity Of Residential Sales In Mass Appraisal Modeling: The Development And Application Of Geographically, Temporally, And Characteristically Weighted Regression, Paul E. Bidanset, Michael Mccord, John R. Lombard, Peadar Davis, William J. Mccluskey

School of Public Service Faculty Publications

Geographically weighted regression (GWR) has been recognized in the assessment community as a viable automated valuation model (AVM) to help overcome, at least in part, modeling hurdles associated with location, such as spatial heterogeneity and spatial autocorrelation of error terms. Although previous researchers have adjusted the GWR weights matrix to also weight by time of sale or by structural similarity of properties in AVMs, the research described in this paper is the first that has done so by all three dimensions (i.e., location, structural similarity, and time of sale) simultaneously. Using 24 years of single-family residential sales in Fairfax, Virginia, …

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Influence Of Macular Pigment Optical Density Spatial Distribution On Intraocular Scatter, Christopher Putnam, Pauline Bland, Carl Bassi Jan 2017

Influence Of Macular Pigment Optical Density Spatial Distribution On Intraocular Scatter, Christopher Putnam, Pauline Bland, Carl Bassi

College of Optometry Faculty Works

No abstract provided.

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Research And Resources, Center For Sea Level Rise, Old Dominion University Jan 2017

Research And Resources, Center For Sea Level Rise, Old Dominion University

Hampton Roads Intergovernmental Pilot Project: Reports

Bibliography of Research and Resources from the Center for Sea Level Rise web site. Reformatted from the web site, March, 2017.

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Secrecy Rates And Optimal Power Allocation For Full-Duplex Decode-And-Forward Relay Wire-Tap Channels, Lubna Elsaid, Leonardo Jimenez-Rodriguez, Nghi H. Tran, Sachin Shetty, Shivakumar Sastry Jan 2017

Secrecy Rates And Optimal Power Allocation For Full-Duplex Decode-And-Forward Relay Wire-Tap Channels, Lubna Elsaid, Leonardo Jimenez-Rodriguez, Nghi H. Tran, Sachin Shetty, Shivakumar Sastry

Computational Modeling & Simulation Engineering Faculty Publications

This paper investigates the secrecy rates and optimal power allocation schemes for a decode-and-forward wiretap relay channel where the transmission from a source to a destination is aided by a relay operating in a full-duplex (FD) mode under practical residual self-interference. By first considering static channels, we address the non-convex optimal power allocation problems between the source and relay nodes under individual and joint power constraints to establish closed-form solutions. An asymptotic analysis is then given to provide important insights on the derived power allocation solutions. Specifically, by using the method of dominant balance, it is demonstrated that full power …

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A Product Structure On Generating Family Cohomology For Legendrian Submanifolds, Ziva Myer Jan 2017

A Product Structure On Generating Family Cohomology For Legendrian Submanifolds, Ziva Myer

Bryn Mawr College Dissertations and Theses

One way to obtain invariants of some Legendrian submanifolds in the standard contact manifolds of 1-jet spaces, J1M, is through the Morse theoretic technique of generating families. This dissertation extends the elective but not complete invariant of generating family cohomology by giving it a product μ2. To define the product, moduli spaces of gradient flow trees are constructed and shown to live as the 0-stratum of a compact smooth manifold with corners. These spaces consist of intersecting gradient trajectories of functions whose critical points correspond to Reeb chords of the Legendrian. This dissertation lays the foundation for an A1 algebra …

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Rapid Quantification Of Trypsin Inhibitors In Food And Feed Formulations With Electrospray Ionization Mass Spectrometry, Radheshyam Panta Jan 2017

Rapid Quantification Of Trypsin Inhibitors In Food And Feed Formulations With Electrospray Ionization Mass Spectrometry, Radheshyam Panta

Doctoral Dissertations

"Presence of anti- nutrients deteriorate the nutritional value of animal foods and feed formulations. The important one being trypsin inhibitors. Trypsin inhibitors in food and feed formulations lower the protein supplement and hence the ultimate consequence is the decrease in growth and development of animals. It is therefore, crucial to monitor trypsin inhibitors in animal food and feed formulations. Research work mentioned in this dissertation is based on the development of rapid, more accurate and robust method for determination of trypsin inhibitor in food and feed formulations. The developed method includes extraction of trypsin inhibitor from food and feed formulation …

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The Maculoprotective Effect Of A Thiol Antioxidant In Retinal Degeneration Models, Hsiu-Jen Wang Jan 2017

The Maculoprotective Effect Of A Thiol Antioxidant In Retinal Degeneration Models, Hsiu-Jen Wang

Doctoral Dissertations

"Age-related macular degeneration (AMD) is a leading cause of irreversible blindness among adults, age 60 and older, in developed countries. While oxidative stress is implicated in the pathogenesis of AMD, clinical studies have shown that dietary antioxidants can delay progression of AMD. Currently, there is no FDA-approved treatment for AMD. Therefore, we hypothesized that N-acetylcysteine amide (NACA), a thiol antioxidant, would protect retinal pigment epithelium and impede the progression of retinal degeneration. The goal of this work was to evaluate the efficacy of NACA in preventing retinal pigment epithelial cell and photoreceptor death in AMD models. To achieve this, we …

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Geophysical Interpretation And Static Reservoir Modeling Of Structurally Complex Reservoir, Rg Oil Field Area, Sirte Basin, Libya, Abdalla A. Abdelnabi Jan 2017

Geophysical Interpretation And Static Reservoir Modeling Of Structurally Complex Reservoir, Rg Oil Field Area, Sirte Basin, Libya, Abdalla A. Abdelnabi

Doctoral Dissertations

"Cambrian-Ordovician and Upper Cretaceous reservoir formations are found in the central western Sirte Basin, the main oil producing region in the Sirte Basin, Libya. As a result of changes in sedimentary environments and structural activities, a number of irregularities in reservoir continuity have developed, which negatively affected the overall performance of the reservoir. Effective simulation of such complex reservoirs can be achieved by integrating geophysical, geological, and petrophysical data to construct a reliable full-field static model, which has the potential to simulate the vertical and lateral variations in the reservoir formations. In this study, 2D and 3D seismic data acquired …

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N-Heterocyclic Carbenes Bearing A Naphthyl Substituent And Their Metal Complexes: Synthesis, Structure, And Application In Catalytic Transfer Hydrogenation, Ayli̇n Ati̇k, Lütfi̇ye Gök Pezük, Hayati̇ Türkmen Jan 2017

N-Heterocyclic Carbenes Bearing A Naphthyl Substituent And Their Metal Complexes: Synthesis, Structure, And Application In Catalytic Transfer Hydrogenation, Ayli̇n Ati̇k, Lütfi̇ye Gök Pezük, Hayati̇ Türkmen

Turkish Journal of Chemistry

A series of unsymmetrical imidazolinium bromides (3a-d) bearing naphthyl and benzyl groups (R' = CH$_{2}$C$_{6}$H$_{2}$(CH$_{3})_{3}$-2,4,6 (a); CH$_{2}$C$_{6}$H(CH$_{3})_{4}$-2,3,5,6 (b); CH$_{2}$C$_{6}$(CH$_{3})_{5}$ (c); CH$_{2}$C$_{6}$F$_{5\, }$(d)) at the N$^{1}$ and N$^{3}$ positions were successfully synthesized. [RuCl$_{2}$(NHC)($p$-cymene)] (NHC= N-heterocyclic carbene) complexes (4a-d) were prepared by the reaction of [RuCl$_{2}(p$-cymene)]$_{2}$ with imidazolinium salts (3a-d). The new salts (3a-d) and their ruthenium(II) complexes (4a-d) were characterized by $^{1}$H, $^{13}$C, $^{19}$F NMR, and elemental analysis. The ruthenium(II) complexes (4a-d) were employed as catalysts for the transfer hydrogenation (TH) of ketones in the presence of KOH using 2-propanol as a hydrogen source and the results were compared. The best …

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Recent Advances In Thymidine Phosphorylase Inhibitors: Syntheses And Prospective Medicinal Applications, Muhammad Aamir Sajid, Zulfiqar Ali Khan, Sohail Anjum Shahzad, Syed Ali̇ Raza Naqvi, Muhammad Usman, Ahsan Iqbal Jan 2017

Recent Advances In Thymidine Phosphorylase Inhibitors: Syntheses And Prospective Medicinal Applications, Muhammad Aamir Sajid, Zulfiqar Ali Khan, Sohail Anjum Shahzad, Syed Ali̇ Raza Naqvi, Muhammad Usman, Ahsan Iqbal

Turkish Journal of Chemistry

This review paper covers recent advances in the synthetic strategies for novel TPase inhibitors and their potential medicinal applications over the last few decades. A brief introduction covering the structural aspects of TPase inhibitors is also included to facilitate understanding of diverse approaches to monitor the design of new inhibitors. TPase is an essential enzyme and its inhibition is a potential target in the development of anticancer drugs.

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Electrochemical Detection Of Dna Interaction With Mannich Base Derivatives By Disposable Graphite Electrodes, Hüseyi̇n İstanbullu, Hakan Karadeni̇z, Erçi̇n Erci̇yas, Kadri̇ye Arzum Erdem Gürsan Jan 2017

Electrochemical Detection Of Dna Interaction With Mannich Base Derivatives By Disposable Graphite Electrodes, Hüseyi̇n İstanbullu, Hakan Karadeni̇z, Erçi̇n Erci̇yas, Kadri̇ye Arzum Erdem Gürsan

Turkish Journal of Chemistry

Four different Mannich base derivatives containing an aromatic/heteroaromatic propanone structure (C1 (3-(dimethylamino)-1-(thiophen-2-yl)propan-1-one hydrochloride); C2 (3-morpholino-1-(pyridin-3-yl)propan-1-one hydrochloride); C3 (3-(dimethylamino)-1-(1H-indol-3-yl)propan-1-one hydrochloride), C4 (3-(piperidin-1-yl)-1-(pyren-1-yl)propan-1-one hydrochloride)) were earlier synthesized and characterized with $^{1}$H NMR, $^{13}$C NMR, MS, and elemental analysis. The interaction of these compounds with fish sperm double stranded DNA (fs-dsDNA) was investigated by using differential pulse voltammetry (DPV) in connection with a disposable pencil graphite electrode (PGE). After the interaction procedure, there was a meaningful decrease in the oxidation signal of the electroactive DNA base guanine due to possible intercalation and/or alkylation mechanism between these Mannich base derivatives and DNA. The features …

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Investigation Of The Effects Of Purification And Characterization Of Turkey (Meleagris Gallopavo) Liver Mitochondrial Thioredoxin Reductase Enzyme And Some Metal Ions On Enzyme Activity, Yusuf Temel, Ö. İrfan Küfrevi̇oğlu, Mehmet Çi̇ftci̇ Jan 2017

Investigation Of The Effects Of Purification And Characterization Of Turkey (Meleagris Gallopavo) Liver Mitochondrial Thioredoxin Reductase Enzyme And Some Metal Ions On Enzyme Activity, Yusuf Temel, Ö. İrfan Küfrevi̇oğlu, Mehmet Çi̇ftci̇

Turkish Journal of Chemistry

The thioredoxin system, found in all living creatures, consists of thioredoxin protein (Trx), thioredoxin reductase enzyme (TrxR), and NADPH. In this study, turkey liver mitochondrial TrxR enzyme with 3.07 EU $\times $ mg$^{-1}$ specific activity was purified 990-fold in a yield of 2.05{\%} using 2',5'-ADP Sepharose 4B affinity chromatography. The purity of the enzyme was measured and the molecular weight of its subunits was determined to be 45.5 kDa by SDS-PAGE. The molecular mass of the enzyme's natural state was found to be 88 kDa using Sephadex-G 150 gel filtration chromatography. In addition, characteristic and kinetic properties of the enzyme …

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Supramolecular Solvent Microextraction Of Uranium At Trace Levels From Water And Soil Samples, Mansoor Khan, Erkan Yilmaz, Mustafa Soylak Jan 2017

Supramolecular Solvent Microextraction Of Uranium At Trace Levels From Water And Soil Samples, Mansoor Khan, Erkan Yilmaz, Mustafa Soylak

Turkish Journal of Chemistry

A supramolecular solvent microextraction procedure was established for the separation/preconcentration of uranium(VI) (U(VI)) prior to its determination by UV-Vis spectrophotometry. 1-(2-Pyridylazo)-2-naphthol (PAN) was used to form a red chelate (U-PAN) with U(VI) at pH 10. U-PAN was extracted by undecanol in tetrahydrofuran. All the parameters that affect extraction efficiency like solution pH, amount of ligand, type and volume of supramolecular solvent, sample volume, and diverse ion effect were optimized. The preconcentration factor was 17. The detection limit was 0.31 $\mu $g L$^{-1}$. The method was validated using GBW07424 (GSS-10 certified reference material). Microextraction was also applied to water and soil …

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Graphite Oxide Catalyzed Synthesis Of $\Beta $-Amino Alcohols By Ring-Opening Of Epoxides, Maryam Mirza-Aghayan, Farzaneh Alvandi, Mahdieh Molaee Tavana, Rabah Boukherroub Jan 2017

Graphite Oxide Catalyzed Synthesis Of $\Beta $-Amino Alcohols By Ring-Opening Of Epoxides, Maryam Mirza-Aghayan, Farzaneh Alvandi, Mahdieh Molaee Tavana, Rabah Boukherroub

Turkish Journal of Chemistry

Graphite oxide as a heterogeneous and recyclable solid acid catalyzed a simple and efficient method for the synthesis of $\beta $-amino alcohols by ring opening of epoxides with amines. This method is effective with various aromatic and aliphatic amines under solvent-free conditions. The corresponding $\beta $-amino alcohols are obtained in high yields (56%-95%) and short reaction times (15-30 min) with high regio- and chemoselectivity under metal-free conditions.

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Synthesis And Antifungal Activity Of New Dihydrofurocoumarins And Dihydrofuroquinolines, Asli Ustalar, Mehmet Yilmaz, Agi̇m Osmani̇, Sema Aşkin Keçeli̇ Jan 2017

Synthesis And Antifungal Activity Of New Dihydrofurocoumarins And Dihydrofuroquinolines, Asli Ustalar, Mehmet Yilmaz, Agi̇m Osmani̇, Sema Aşkin Keçeli̇

Turkish Journal of Chemistry

We investigated the radical addition of 4-hydroxycoumarin (1a) and 4-hydroxyquinoline (1b) with conjugated dienes ({2a-f) mediated by cerium(IV) ammonium nitrate (CAN) resulting in ethenyl substituted 2,3-dihydrofurocoumarin (3a-f) and 3,5-dihydrofuroquinoline (3g, 3h) compounds in moderate to good yields. All compounds were characterized by spectroscopic methods (IR, MS, and $^{1}$H and $^{13}$C NMR) and microanalysis. Antifungal activities of these compounds were investigated against the fungi Candida albicans, C. parapsilosis, C. krusei, C. glabrata, C. tropicalis, and Aspergillus fumigatus.

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Highly Selective Schiff Base Derivatives For Colorimetric Detection Of Al$^{3+}$, Zi̇ya Aydin, Mustafa Keleş Jan 2017

Highly Selective Schiff Base Derivatives For Colorimetric Detection Of Al$^{3+}$, Zi̇ya Aydin, Mustafa Keleş

Turkish Journal of Chemistry

Schiff base derivatives NBAR and NSAR were developed for selective detection of Al$^{3+}$ in aqueous solution. UV-vis spectroscopic studies revealed that NBAR and NSAR showed marked sensitivity and selectivity to Al$^{3+}$ in acetonitrile (ACN)/water (v/v, 1:1, pH 6.80). The NBAR and NSAR receptors bound Al$^{3+}$ in a 2:1 stoichiometry with apparent binding constants 4.09 $\times $ 10$^{11}$ M$^{-2}$ and 1.65 $\times $ 10$^{12}$ M$^{-2}$, respectively. They also displayed distinct changes in color upon the alteration of free Al$^{3+}$ levels in solution with reversible responses and showed little interference with other metal ions.

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Voltammetric Analysis Of Disulfiram In Pharmaceuticals With A Cyclic Renewable Silver Amalgam Film Electrode, Sylwia Smarzewska, Natalia Festinger, Monika Skowron, Dariusz Guziejewski, Radovan Metelka, Mariola Brycht, Witold Ciesielski Jan 2017

Voltammetric Analysis Of Disulfiram In Pharmaceuticals With A Cyclic Renewable Silver Amalgam Film Electrode, Sylwia Smarzewska, Natalia Festinger, Monika Skowron, Dariusz Guziejewski, Radovan Metelka, Mariola Brycht, Witold Ciesielski

Turkish Journal of Chemistry

Electrochemical properties of disulfiram, representative of highly significant bioactive compounds, were studied with a cyclic renewable silver amalgam film electrode (Hg(Ag)FE) using square wave cathodic stripping voltammetry (SWCSV). The influence of various factors such as pH, buffer concentration, buffer composition, and SWCSV parameters on current response was investigated. The optimum results in terms of signal shape and intensity were recorded in Britton--Robinson buffer (pH 7.5) at -0.5 V versus Ag/AgCl/3 mol L$^{-1}$ KCl. An elaborated electroanalytical procedure was used to determine disulfiram at the Hg(Ag)FE in the concentration range from 0.05 to 5.00 $\mu $M. Precision, repeatability, and accuracy of …

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Synthesis And Cytotoxicity Of Novel Thioxo-Quinazolino[3,4-$A$]Quinazolinones, Negar Mohammadhosseini, Mina Saeedi, Shahram Moradi, Mohammad Mahdavi, Omidreza Firuzi, Alireza Foroumadi, Abbas Shafiee Jan 2017

Synthesis And Cytotoxicity Of Novel Thioxo-Quinazolino[3,4-$A$]Quinazolinones, Negar Mohammadhosseini, Mina Saeedi, Shahram Moradi, Mohammad Mahdavi, Omidreza Firuzi, Alireza Foroumadi, Abbas Shafiee

Turkish Journal of Chemistry

Various thioxo-quinazolino[3,4-$a$]quinazolinones were prepared and evaluated for their cytotoxicity in MOLT-4 (lymphoblastic leukemia) and MCF-7 (breast adenocarcinoma) cell lines. Synthesis of the target compounds was started from isatoic anhydride. Successive reaction of isatoic anhydride with benzylamine and 2-nitrobenzaldehyde, reduction of the nitro group, and reaction with CS$_{2}$ gave 12-benzyl-6-thioxo-6,7,11b,12-tetrahydro-13$H$-quinazolino[3,4-$a$]quinazolin-13-one. The latter compound reacted with various 2-chloro-$N$-substituted acetamides to afford the corresponding fused quinazolinone derivatives.

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Synthesis And Characterization Of Magnetic Amidoximated Chitosan-G Poly(Polyacrylonitrile)/Laponite Rd Nanocomposites With Enhanced Adsorption Capacity For Cu$^{2+}$, Gholam Reza Mahdavinia, Ebrahim Shokri Jan 2017

Synthesis And Characterization Of Magnetic Amidoximated Chitosan-G Poly(Polyacrylonitrile)/Laponite Rd Nanocomposites With Enhanced Adsorption Capacity For Cu$^{2+}$, Gholam Reza Mahdavinia, Ebrahim Shokri

Turkish Journal of Chemistry

Magnetic amidoximated nanocomposites based on a combination of chitosan and magnetic laponite RD were prepared and examined for the removal of Cu$^{2+}$ from aqueous solutions. Magnetic laponite RD was prepared by an in situ method. In order to prepare magnetic amidoximated nanocomposites, acrylonitrile was grafted to chitosan in the presence of magnetic laponite RD. Then the nitrile pendants on magnetic chitosan-g-polyacrylonitrile/laponite RD (mChtioPANLap) were converted to amidoxime groups. We developed a polyamidoximated magnetic nanocomposite based on a mixture of chitosan/laponite RD, possessing a high adsorption capacity for Cu$^{2+}$. By introducing magnetic laponite RD the adsorption capacity of nanocomposites for Cu$^{2+}$ …

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Homopolymerization And Synthesis Of A New Methacrylate Monomer Bearing A Boron Side Group: Characterization And Determination Of Monomer Reactivity Ratios With Styrene, Tuba Çakir Çanak, Serkan Akpinar, İ. Ersi̇n Serhatli Jan 2017

Homopolymerization And Synthesis Of A New Methacrylate Monomer Bearing A Boron Side Group: Characterization And Determination Of Monomer Reactivity Ratios With Styrene, Tuba Çakir Çanak, Serkan Akpinar, İ. Ersi̇n Serhatli

Turkish Journal of Chemistry

Boron methacrylate (BAc) monomer was synthesized via an esterification reaction. Boric acid, neopentyl glycol, and 2-hydroxyethyl methacrylate (HEMA) were reacted to obtain boron-containing acrylic monomer. Characterization was achieved by FT-IR, $^{13}$C NMR, $^{1}$H NMR, and $^{11}$B NMR and the results for the synthesized monomer were compared to those for HEMA. Homopolymer and copolymers with styrene (St) were synthesized via free radical polymerization. The properties of the synthesized styrene copolymers were investigated using several techniques. Monomer reactivity ratios for the studied monomer pair were calculated using the extended Kelen-Tüdos method. Copolymerization compositions and reactive ratios showed that the obtained copolymers had …

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