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2013

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Articles 18811 - 18840 of 20110

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Synthesis Of Novel Benzimidazole Salts And Microwave-Assisted Catalytic Activity Of In Situ Generated Pd Nanoparticles From A Catalyst System Consisting Of Benzimidazol Salt, Pd(Oac)_2, And Base In A Suzuki-Miyaura Reaction, Ülkü Yilmaz, Hasan Küçükbay, Sevi̇m Türkteki̇n Çeli̇kesi̇r, Mehmet Akkurt, Orhan Büyükgüngör Jan 2013

Synthesis Of Novel Benzimidazole Salts And Microwave-Assisted Catalytic Activity Of In Situ Generated Pd Nanoparticles From A Catalyst System Consisting Of Benzimidazol Salt, Pd(Oac)_2, And Base In A Suzuki-Miyaura Reaction, Ülkü Yilmaz, Hasan Küçükbay, Sevi̇m Türkteki̇n Çeli̇kesi̇r, Mehmet Akkurt, Orhan Büyükgüngör

Turkish Journal of Chemistry

Novel benzimidazolium salts having N-benzyl or N-(4-substitutedbenzyl) groups were synthesized and their microwave-promoted catalytic activity for the Suzuki--Miyaura cross-coupling reaction were determined using in situ formed palladium(0) nanoparticles (PdNPs) from a catalytic system consisting of Pd(OAc)_2/K2CO_3 in DMF/H_2O. PdNPs were characterized by X-ray diffraction (XRD) pattern and particle size of in situ generated PdNPs from the Pd(111) plane was determined to be of diameter 19.6 nm by the Debye--Scherrer equation. Moreover, the yield of the Suzuki--Miyaura reactions with aryl iodides and aryl bromides was found to be nearly quantitative. The synthesized benzimidazole salts (1--5) were identified by ^1H and ^{13}C …

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Optimization Of Synthesizing Glucose 1-Phosphate By Sodium Tripolyphosphate As A Phosphorus Acylating Agent Using Response Surface Methodology, Li 'E Jin, Fenfen Chang, Xiao Juan Wang, Qing Cao Jan 2013

Optimization Of Synthesizing Glucose 1-Phosphate By Sodium Tripolyphosphate As A Phosphorus Acylating Agent Using Response Surface Methodology, Li 'E Jin, Fenfen Chang, Xiao Juan Wang, Qing Cao

Turkish Journal of Chemistry

With glucose as the starting material, sodium tripolyphosphate as the phosphorus acylating agent, and urea as the catalyst, glucose 1-phosphate was synthesized and its properties were analyzed. The synthesis conditions were selected according to the phosphorus content and optimized through the response surface methodology (RSM), based on a 3-level, 3-variable Box--Behnken experimental design. The results showed that the phosphorus content of glucose 1-phosphate was 8.12% using a reaction temperature of 70 °C, a molar ratio of glucose to sodium tripolyphosphate of 1.54:1, and catalyst amount of 3.7 g. It coincided well with the experimental value (8.34%). The structure of the …

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Poly(4-Vinylpyridine)-Supported Dual Acidic Ionic Liquid: An Environmentally Friendly Heterogeneous Catalyst For The One-Pot Synthesis Of 4,4'-(Arylmethylene)Bis(3-Methyl-1-Phenyl-1h-Pyrazol-5-Ols), Kaveh Parvanak Boroujeni, Pegah Shojaei Jan 2013

Poly(4-Vinylpyridine)-Supported Dual Acidic Ionic Liquid: An Environmentally Friendly Heterogeneous Catalyst For The One-Pot Synthesis Of 4,4'-(Arylmethylene)Bis(3-Methyl-1-Phenyl-1h-Pyrazol-5-Ols), Kaveh Parvanak Boroujeni, Pegah Shojaei

Turkish Journal of Chemistry

A poly(4-vinylpyridine)-supported Brønsted ionic liquid was easily prepared from its starting materials and used as a novel, highly efficient, and reusable heterogeneous catalytic system for the synthesis of 4,4'-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ols) from the condensation reaction between aromatic aldehydes and 2 equivalents of 3-methyl-l-phenyl-5-pyrazolone.

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Aerosol-Assisted Chemical Vapor Deposition Of Copper Sulfide Nanostructured Thin Film From Newly Synthesized Single-Source Precursor, Sohail Saeed, Naghmana Rashid, Khurram Shahzad Ahmad Jan 2013

Aerosol-Assisted Chemical Vapor Deposition Of Copper Sulfide Nanostructured Thin Film From Newly Synthesized Single-Source Precursor, Sohail Saeed, Naghmana Rashid, Khurram Shahzad Ahmad

Turkish Journal of Chemistry

The copper(II) complex of N-[ethyl(butyl)carbamothioyl]- 3,5-dinitrobenzamide (1) has been synthesized and characterized by elemental analysis, IR spectroscopy, and atmospheric pressure chemical ionization-mass spectrometry. Thermogravimetric analysis shows that complex 2 decomposes in 2 steps to form copper sulfide. The complex was used as a single-source precursor for the deposition of copper sulfide thin film by aerosol-assisted chemical vapor deposition at 350 °C. The powder X-ray diffraction pattern of thin film of the complex showed the deposition of monoclinic roxbyite Cu_7S_4 and orthorhombic anilite Cu_7S_4 phases at 350 °C with spherical crystallites. The degree of film surface roughness was determined by atomic …

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Palladium-Edta And Palladium-Edteh_4 Catalyzed Heck Coupling Reactions In Pure Water, Süleyman Gülcemal, Beki̇r Çeti̇nkaya Jan 2013

Palladium-Edta And Palladium-Edteh_4 Catalyzed Heck Coupling Reactions In Pure Water, Süleyman Gülcemal, Beki̇r Çeti̇nkaya

Turkish Journal of Chemistry

Palladium-catalyzed Heck coupling reactions of styrene with bromoarene derivatives are carried out under aerobic conditions in water using water-soluble N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (EdteH_4) and ethylenediaminetetraacetic acid disodium salt (Na_2EDTA) as ligands. The effect of different bases, catalyst loading, and additives is also monitored. The olefination of bromoarenes with styrene affords the desired products in high yields. The Na_2PdCl_4-Na_2EDTA precatalyst system is also used for the preparative scale (50.0 mmol) synthesis of 4-acetyl-trans-stilbene and 4-styrylbenzaldehyde without a noticeable decrease in the activity. Recycling studies on the Na_2PdCl_4 - Na_2EDTA precatalyst system are also tested in the coupling of 4-bromoacetophenone with styrene.

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Synthesis Of 3,4-Diaryl-1-Phenyl-4,5-Dihydro-1h-Pyrazole-5-Carbonitriles Via 1,3-Dipolar Cycloaddition Reactions, Jayaroopa Prabhashankar, Vasanth Kumar Govindappa, Ajay Kumar Kariyappa Jan 2013

Synthesis Of 3,4-Diaryl-1-Phenyl-4,5-Dihydro-1h-Pyrazole-5-Carbonitriles Via 1,3-Dipolar Cycloaddition Reactions, Jayaroopa Prabhashankar, Vasanth Kumar Govindappa, Ajay Kumar Kariyappa

Turkish Journal of Chemistry

Nitrile imines generated by the oxidative dehydrogenation of aromatic aldehyde phenylhydrazones with chloramine-T as a catalytic dehydrogenating agent were trapped in situ by 4-methoxy cinnamonitrile to afford 3,4-diaryl-1-phenyl-4,5-dihydro-1H-pyrazole-5-carbonitrile in moderate to good yields. The structures of the cycloadducts were confirmed by spectral studies and elemental analysis.

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Synthesis, Characterization, And Fluorescence Study Of Phthalhydrazidylazo Derivative Of An Unsaturated Diketone And Its Metal Complexes, Radhika Pallikkavil, Muhammed Basheer Ummathur, Krishnannair Krishnankutty Jan 2013

Synthesis, Characterization, And Fluorescence Study Of Phthalhydrazidylazo Derivative Of An Unsaturated Diketone And Its Metal Complexes, Radhika Pallikkavil, Muhammed Basheer Ummathur, Krishnannair Krishnankutty

Turkish Journal of Chemistry

The coupling of diazotized luminol with the unsaturated diketone 1,7-diphenylhepta-4,6-diene-1,3-dione yielded a new type of tridentate ligand (H_2L). Analytical, IR, ^1H NMR, and mass spectral data indicate the existence of the compound in the intramolecularly hydrogen-bonded keto-hydrazone tautomeric form. Dibasic tridentate coordination of the compound in its [ML(H_2O)] complexes [M = Cu(II), Ni(II) and Zn(II)] was established on the basis of analytical and spectral data. The Ni(II) and Zn(II) chelates are diamagnetic while Cu(II) complex showed normal paramagnetic moment. The fluorescence maxima of the compound in different solvents show that the emission wavelength increases with increases in the polarity of …

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Comparative Study Of Microwave-Assisted And Conventional Synthesis Of Ibuprofen-Based Acyl Hydrazone Derivatives, Ayşe Uzgören Baran Jan 2013

Comparative Study Of Microwave-Assisted And Conventional Synthesis Of Ibuprofen-Based Acyl Hydrazone Derivatives, Ayşe Uzgören Baran

Turkish Journal of Chemistry

A series of potential biological active acyl hydrazone derivatives containing ibuprofen moiety (compounds 4a--4p) was synthesized by the condensation of ibuprofen hydrazone with aromatic aldehydes using conventional and microwave irradiation methods. The microwave method was found to be successful with nearly the same or higher yields and shorter reaction time, and it was more environmentally friendly compared to the conventional heating method. The chemical structures of the synthesized compounds were characterized by IR, ^1H NMR, and APT-NMR spectroscopy.

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Syntheses, Characterization, And Antibacterial Study Of Titanium Complexes, Raj Kaushal, Nitesh Kumar, Pamita Awasthi, Kiran Nehra Jan 2013

Syntheses, Characterization, And Antibacterial Study Of Titanium Complexes, Raj Kaushal, Nitesh Kumar, Pamita Awasthi, Kiran Nehra

Turkish Journal of Chemistry

Titanium(II) complexes of composition TiCl_2(L)_2 [where L = 2,2'-bipyridine (bipy), 4,4'-dimethyl-2,2'-bipyridine (bpMe), 4,4'-dimethoxy-2,2'-bipyridine (bpoMe), 6,6'-dimethyl-2,2'-bipyridine (dpMe), adamantylamine (ada)] were prepared by reacting titanium tetrachloride and N-containing bulky ligands in predetermined molar ratios. The complexes synthesized were characterized by different spectroscopic techniques, viz. UV-visible, FTIR, ^1H NMR, and mass spectrometry. The stoichiometry of the complexes was established by their elemental analysis (chlorine and titanium estimation). The unit cell parameters calculated by using the powder XRD tool confirm the monoclinic unit system and P lattice type for all complexes. Antibacterial screening of the ligands as well as the complexes was carried out …

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Synthesis, Characterization, And Dft Calculation Of A Pd(Ii) Schiff Base Complex, Alireza Akbari, Zahra Alinia Jan 2013

Synthesis, Characterization, And Dft Calculation Of A Pd(Ii) Schiff Base Complex, Alireza Akbari, Zahra Alinia

Turkish Journal of Chemistry

The 4-((E)-(2-((E)-2, 4-dihydroxybenzylideneamino) ethylimino) methyl) benzene-1,3-diol tetradentate ligand, H_2L, reacted with PdCl_2 to produce the related complex. The complex was characterized by elemental analysis, infrared and electronic spectroscopy, thermogravimetric study, and molar conductance. Furthermore, the fully optimized geometries were calculated using the ADF 2009.01 package. Comparison between the calculated and experimental results covering molecular structures, assignment of fundamental vibrational modes, and thermodynamic properties were investigated. The optimized molecular geometries were compared with the experimental data obtained from X-ray data of a similar complex, which indicated that the theoretical results agree with the corresponding experimental values. The UV-Vis spectrum of the …

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Synthesis, Characterization, And Biological Activity Of Coordination Polymers Derived From Pyromellitic Dianhydride, Yogesh Patel, Ritu Dixit, Hasmukh Shanubhai Patel Jan 2013

Synthesis, Characterization, And Biological Activity Of Coordination Polymers Derived From Pyromellitic Dianhydride, Yogesh Patel, Ritu Dixit, Hasmukh Shanubhai Patel

Turkish Journal of Chemistry

A new ligand, 2,5-bis(furan-2-ylmethylcarbamoyl)terephthalic acid (BFMTA), was synthesized using 1,2,4,5-benzenetetracarboxylic dianhydride (pyromellitic dianhydride-PMDA) with furan-2-ylmethanamine (2-furfurylamine). New coordination polymers of the ligand (BFMTA) were also prepared using transition metal ions Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) metal salts. The coordination polymers and ligand were characterized by physico-chemical characteristics, magnetic susceptibilities, spectroscopic investigations, and thermogravimetry. Antimicrobial activity was tested using the agar-plate method against various strains of bacteria and spores of fungi. The results showed significantly higher antimicrobial activity of coordination polymers compared to the ligand.

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Simple And Convenient Preparation Of Novel 6,8-Disubstituted Quinoline Derivatives And Their Promising Anticancer Activities, Sali̇h Ökten, Osman Çakmak, Ramazan Erenler, Önem Yüce Şahi̇n, Şaban Teki̇n Jan 2013

Simple And Convenient Preparation Of Novel 6,8-Disubstituted Quinoline Derivatives And Their Promising Anticancer Activities, Sali̇h Ökten, Osman Çakmak, Ramazan Erenler, Önem Yüce Şahi̇n, Şaban Teki̇n

Turkish Journal of Chemistry

A short and easy route is described for 6,8-disubstituted derivatives of quinoline and 1,2,3,4-tetrahydroquinoli- ne from 6,8-dibromoquinolines 2 and 7 by various substitution reactions. While copper-promoted substitution of 6,8-dibromide 2 produced monomethoxides 3 and 4, a prolonged reaction time mainly afforded dimethoxide 6 instead of 5, whose aromatization with DDQ and substitution reaction of dibromide 7 with NaOMe in the presence of CuI also gave rise to dimethoxide 6. Several 6,8-disubstituted quinolines were obtained by treatment of 6,8-dibromoquinoline (7) with n-BuLi followed by trapping with an electrophile [Si(Me)_3Cl, S_2(Me)_2, and DMF]. Furthermore, 7 was also converted to mono and dicyano …

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Synthesis Of Tetrakis(Carboxyphenyl)Porphyrin Coated Paramagnetic Iron Oxide Nanoparticles Via Amino Acid For Photodegradation Of Methylene Blue, Rahmatollah Rahimi, Azadeh Tadjarodi, Mina Imani, Mahboubeh Rabbani, Samaneh Safalou Moghaddam, Hamed Kerdari Jan 2013

Synthesis Of Tetrakis(Carboxyphenyl)Porphyrin Coated Paramagnetic Iron Oxide Nanoparticles Via Amino Acid For Photodegradation Of Methylene Blue, Rahmatollah Rahimi, Azadeh Tadjarodi, Mina Imani, Mahboubeh Rabbani, Samaneh Safalou Moghaddam, Hamed Kerdari

Turkish Journal of Chemistry

In this paper, synthesis of tetrakis(carboxyphenyl)porphyrin (TCPP) coated cadmium ferrite (CdFe_2O_4) nanoparticles by using L-lysine as an anchor is reported for the first time. The ferrimagnetic CdFe_2O_4 nanoparticles were prepared via the facile self-assembly method of reflux followed by a heating treatment. The obtained magnetic nanoparticles were coated with TCPP in the presence of the amino acid L-lysine by sonication in ethanol and then refluxing for 12 h. The structural characteristics of the products were determined using FT-IR and XRD pattern. Scanning electron microscopy (SEM) images indicated uniform morphologies of the magnetic nanoparticles with an average size of 43 nm. …

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Novel Flame Retardant Poly(Thiourea-Sulfone-Imide)S For High Temperature Applications: Synthesis And Characterization, Ghulam Waris, Humaira Masood Siddiqi, Lance Twyman, Rizwan Hussain, Zareen Akhter, Muhammad Saeed Butt Jan 2013

Novel Flame Retardant Poly(Thiourea-Sulfone-Imide)S For High Temperature Applications: Synthesis And Characterization, Ghulam Waris, Humaira Masood Siddiqi, Lance Twyman, Rizwan Hussain, Zareen Akhter, Muhammad Saeed Butt

Turkish Journal of Chemistry

The synthesis and polymerization of a novel diamine monomer, 1,1-(sulfonylbis (4,1-phenylene)) bis (thiourea) (SPT), with various aromatic dianhydrides were carried out. In addition, the fabrication of poly(thiourea-sulfone-imide)s (PTSIs) with noble thermal properties and flame retardancy was conducted. The structures of SPT and polymers were characterized by FT-IR, ^1H NMR, and ^{13}C NMR spectroscopy along with elemental analysis. Crystallinity, organosolubility, inherent viscosity, and gel permeation chromatographic measurements were taken as well. The amorphous nature was exhibited by PTSIs containing C=S and --SO_2- moieties in the backbone that were readily soluble in highly polar organic solvents. The inherent viscosities of PTSIs were …

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Synthesis Of New N-[3-(Benzo[D]Thiazol-2-Yl)-4-Methylthiazol-2(3h)-Ylidene] Substituted Benzamides, Aamer Saeed, Hummera Rafique Jan 2013

Synthesis Of New N-[3-(Benzo[D]Thiazol-2-Yl)-4-Methylthiazol-2(3h)-Ylidene] Substituted Benzamides, Aamer Saeed, Hummera Rafique

Turkish Journal of Chemistry

A series of novel N-[3-(2-benzo[d]thiazol-2-yl)-4-methylthiazol-2(3H)-ylidene] substituted benzamides (2a--k) were efficiently synthesized by heterocyclization of the corresponding 1-(benzo[d]thiazol-2-yl)-3-aroylthioureas (1a--k). The cyclization was achieved by the reaction of \alpha-bromoacteone produced in situ using bromine in dry acetone in the presence of triethylamine.

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Electrochemical Determination Of Sudan Iv In Food Samples By Using Graphene-Modified Glassy Carbon Electrodes, Meifeng Chen, Xinying Ma, Xia Li Jan 2013

Electrochemical Determination Of Sudan Iv In Food Samples By Using Graphene-Modified Glassy Carbon Electrodes, Meifeng Chen, Xinying Ma, Xia Li

Turkish Journal of Chemistry

A simple and sensitive modified electrode was fabricated with graphene via the drop-casting method and applied for the electrochemical detection of Sudan IV. Cyclic voltammetry (CV) was used to investigate the electrochemical behaviors of Sudan IV in phosphate buffer solution (PBS). The experimental conditions such as determining medium, scan rate, and accumulation time were optimized for the determination of Sudan IV. The sensor has excellent performance associated with high sensitivity, a low detection limit (6.00 \times 10^{-8} M), and a wide linear range of 2.00 \times 10^{-7} M to 8.00 \times 10^{-5} M with a correlation coefficient as follows: i_{pc} …

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N-Functionalized Benzimidazol-2-Ylidene Silver Complexes: Synthesis, Characterization, And Antimicrobial Studies, Yetki̇n Gök, Senem Akkoç, Özlem Özeroğlu Çeli̇kal, İlknur Özdemi̇r, Selami̇ Günal, Eli̇f Sayin Jan 2013

N-Functionalized Benzimidazol-2-Ylidene Silver Complexes: Synthesis, Characterization, And Antimicrobial Studies, Yetki̇n Gök, Senem Akkoç, Özlem Özeroğlu Çeli̇kal, İlknur Özdemi̇r, Selami̇ Günal, Eli̇f Sayin

Turkish Journal of Chemistry

2-Methoxyethyl, 2-diethylaminoethyl, and 2-phenylethyl-substituted N-heterocyclic carbene (NHC) precursors were treated with Ag_2CO_3 to yield silver(I)-NHC complexes (1a--g) in dichloromethane as a solvent at room temperature. The 7 new silver-NHC complexes were fully characterized by means of ^1H NMR, ^{13}C NMR, and elemental analysis techniques. Using the agar dilution procedure recommended by the Laboratory and Clinical Standards Institute, the antimicrobial activities of all the silver-NHC complexes were studied against 2 gram-negative bacterial strains (Pseudomonas aeruginosa and Escherichia coli), 2 gram-positive bacterial strains (Enterococcus faecalis and Staphylococcus aureus), and 2 fungi (Candida tropicalis and Candida albicans).

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Review Of Us And Eu Initiatives Toward Development, Demonstration, And Commercialization Of Lignocellulosic Biofuels, Venkatesh Balan, David Chiaramonti, Sandeep Kumar Jan 2013

Review Of Us And Eu Initiatives Toward Development, Demonstration, And Commercialization Of Lignocellulosic Biofuels, Venkatesh Balan, David Chiaramonti, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

Advanced biofuels produced from lignocellulosic biomass offer an exciting opportunity to produce renewable liquid transportation fuels, biochemicals, and electricity from locally available agriculture and forest residues. The growing interest in biofuels from lignocellulosic feedstock in the United States (US) and the European Union (EU) can provide a path forward toward replacing petroleum-based fuels with sustainable biofuels which have the potential to lower greenhouse gas (GHG) emissions. The selection of biomass conversion technologies along with feedstock development plays a crucial role in the commercialization of next-generation biofuels. There has been synergy and, even with similar basic process routes, diversity in the …

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Flexural Rigidity Characterization Of Retrofitted Frp Plates, Steven J. Makonis Jr., Stella B. Bondi, Zia Razzaq Jan 2013

Flexural Rigidity Characterization Of Retrofitted Frp Plates, Steven J. Makonis Jr., Stella B. Bondi, Zia Razzaq

Civil & Environmental Engineering Faculty Publications

Presented herein is a procedure and numerical results for flexural rigidity characterization of Fiber Reinforced Polymer (FRP) plates retrofitted with various types of fabrics. The FRP plates were retrofitted with Kevlar® 49 (Aramid), Carbon Fiber (Harness-Satin H5), and Unidirectional Carbon Fiber (T700 Aerospace Grade) fabrics, respectively. The FRP plate flexural rigidity values were calculated with a central finitedifference iterative scheme while utilizing the experimental load-deflection relations based on bending tests. The tests were performed on each plate by applying a concentrated load at the center. A fourth-order partial differential equation of plate equilibrium was adopted to estimate the plate flexural …

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Stromatolites And Miss—Differences Between Relatives, N. Noffke, S. M. Awramik Jan 2013

Stromatolites And Miss—Differences Between Relatives, N. Noffke, S. M. Awramik

OES Faculty Publications

Benthic microorganisms form highly organized communities called “biofilms.” A biofilm consists of the individual cells plus their extracellular polymeric substances (EPS). In marine and non-marine environments, benthic microbial communities interact with the physical sediment dynamics and other factors in the environment in order to survive. This interaction can produce distinctive sedimentary structures called microbialites. Binding, biostabilization, baffling, and trapping of sediment particles by microorganisms result in the formation of microbially induced sedimentary structures (MISS); however, if carbonate precipitation occurs in EPS, and these processes happen in a repetitive manner, a multilayered build-up can form—stromatolites. Stromatolites and MISS are first found …

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Microbially Induced Sedimentary Structures Recording An Ancient Ecosystem In The Ca. 3.48 Billion-Year-Old Dresser Formation, Pilbara, Western Australia, Nora Noffke, Daniel Christian, David Wacey, Robert M. Hazen Jan 2013

Microbially Induced Sedimentary Structures Recording An Ancient Ecosystem In The Ca. 3.48 Billion-Year-Old Dresser Formation, Pilbara, Western Australia, Nora Noffke, Daniel Christian, David Wacey, Robert M. Hazen

OES Faculty Publications

Microbially induced sedimentary structures (MISS) result from the response of microbial mats to physical sediment dynamics. MISS are cosmopolitan and found in many modern environments, including shelves, tidal flats, lagoons, riverine shores, lakes, interdune areas, and sabkhas. The structures record highly diverse communities of microbial mats and have been reported from numerous intervals in the geological record up to 3.2 billion years (Ga) old. This contribution describes a suite of MISS from some of the oldest well-preserved sedimentary rocks in the geological record, the early Archean (ca. 3.48 Ga) Dresser Formation, Western Australia. Outcrop mapping at the meter to …

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Distributions Of Particulate Heme B In The Atlantic And Southern Oceans- Implications For Electron Transport In Phytoplankton, Martha Gledhill, Eric P. Achterberg, David J. Honey, Maria C. Nielsdottir, Micha J.A. Rijkenberg Jan 2013

Distributions Of Particulate Heme B In The Atlantic And Southern Oceans- Implications For Electron Transport In Phytoplankton, Martha Gledhill, Eric P. Achterberg, David J. Honey, Maria C. Nielsdottir, Micha J.A. Rijkenberg

OES Faculty Publications

Concentrations of heme b, the iron-containing component of b-type hemoproteins, ranged from b concentrations were enhanced in the photic zone and decreased with depth. Heme b concentrations correlated positively with chlorophyll a (chl a) in the TNA (r=0.41, pb did not correlate with chl a in the IB or SS. In the IB and SS, stations with high-chlorophyll and low-nutrient (Fe and/or Si) concentrations exhibited low heme bconcentrations relative to particulate organic carbon (< 0.1 μmolmol-1, and high chl a:heme b ratios (> 500). High chl a:heme b ratios resulted from relative decreases in …

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Synthesis And Characterization Of Thermally Stable Camphor-Based Polyimide--Clay Nanocomposites, Murat Yi̇ği̇t, Turgay Seçki̇n, Beyhan Yi̇ği̇t, Süleyman Köytepe Jan 2013

Synthesis And Characterization Of Thermally Stable Camphor-Based Polyimide--Clay Nanocomposites, Murat Yi̇ği̇t, Turgay Seçki̇n, Beyhan Yi̇ği̇t, Süleyman Köytepe

Turkish Journal of Chemistry

A new monomer was prepared from (1R,3S)-(+)-camphoric acid. Novel polyimide and polyimide--clay hybrid composites were developed from one-pot condensation reactions of this monomer and pyromellitic dianhyride. Polyimide-montmorillonite nanocomposites were prepared from solution of polyimide and with different weight percentages (1, 5, 10 wt %) of organo-modified montmorillonite (OM-MMT) using N-methyl-2-pyrrolidone (NMP) as aprotic solvent. The reactive organoclay was formed by using hexadecylpyridinium chloride as a swelling agent for silicate layers of montmorillonite. The polyimide--clay composites films (PI--MMT) were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD). All composites were subjected to differential scanning calorimetry …

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Synthesis And Cytotoxic Activity Of Some 2-(2,3-Dioxo-2,3-Dihydro-1h-Indol-1-Yl)Acetamide Derivatives, Özlem Akgül, Ayşe Hande Tari̇koğullari, Fadi̇me Aydin Köse, Petek Ballar Kirmizibayrak, Mehmet Varol Pabuççuoğlu Jan 2013

Synthesis And Cytotoxic Activity Of Some 2-(2,3-Dioxo-2,3-Dihydro-1h-Indol-1-Yl)Acetamide Derivatives, Özlem Akgül, Ayşe Hande Tari̇koğullari, Fadi̇me Aydin Köse, Petek Ballar Kirmizibayrak, Mehmet Varol Pabuççuoğlu

Turkish Journal of Chemistry

Isatin, 1H-indoline-2,3-dione, an endogenous compound, is also a synthetically versatile molecule that possesses a diversity of biological activities including anticonvulsant, antibacterial, antifungal, antiviral, anticancer, and cytotoxic properties. Based on the promising cytotoxic activity studies on N-substituted isatin derivatives, a series of 18 derivatives of 2-(2,3-dioxo-2,3-dihydro- 1H-indol-1-yl)-N-phenylacetamide were designed, synthesized, and characterized according to their analytical and spectral data. All of the compounds were evaluated for their cytotoxic activity against MCF7, A549, HeLa, and HEK293 cell lines by real time cell analyzer. Etoposide was used as a standard compound. Briefly, ortho substitutions gave better results compared to meta and para substitutions …

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A One-Pot Strategy For Regioselective Synthesis Of 6-Aryl-3-Oxo-2,3-Dihydropyridazine-4-Carbohydrazides, Mehdi Rimaz, Hossein Mousavi Jan 2013

A One-Pot Strategy For Regioselective Synthesis Of 6-Aryl-3-Oxo-2,3-Dihydropyridazine-4-Carbohydrazides, Mehdi Rimaz, Hossein Mousavi

Turkish Journal of Chemistry

A simple and efficient method for the synthesis of 6-aryl-3-oxo-2,3-dihydropyridazine-4-carbohydrazide derivatives was developed. The synthesis was achieved via one-pot multicomponent reaction of arylglyoxals, dialkylmalonates, and hydrazine hydrate in pyridine at room temperature. This procedure features high regioselectivity, generally good to excellent yields, the use of easily available starting materials, and operational simplicity. This chemistry provides an efficient and promising synthetic strategy for diversity-oriented construction of the 6-arylpyridazinone skeleton.

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Antimicrobial Activity And Chemical Composition Of The Essential Oils Of Mosses (Hylocomium Splendens (Hedw.) Schimp. And Leucodon Sciuroides (Hedw.) Schwägr.) Growing In Turkey, Tayyi̇be Beyza Cansu, Büşra Yayli, Turan Özdemi̇r, Nevzat Batan, Şengül Alpay Karaoğlu, Nuretti̇n Yayli Jan 2013

Antimicrobial Activity And Chemical Composition Of The Essential Oils Of Mosses (Hylocomium Splendens (Hedw.) Schimp. And Leucodon Sciuroides (Hedw.) Schwägr.) Growing In Turkey, Tayyi̇be Beyza Cansu, Büşra Yayli, Turan Özdemi̇r, Nevzat Batan, Şengül Alpay Karaoğlu, Nuretti̇n Yayli

Turkish Journal of Chemistry

In the present work, the volatiles of mosses [Hylocomium splendens (Hedw.) Schimp. (Hylocomiaceae) and Leucodon sciuroides (Hedw.) Schwägr. (Leucodontaceae)] have been investigated by GC-FID and GC/MS. Fifty-eight compounds in the oil of H. splendens, representing 75.4%, and 41 compounds in the oil of L. sciuroides, representing 87.6%, were identified. The major components were found to be \beta-pinene (11.6%) and \alpha-pinene (8.9%) in the oil of H. splendens, and nonanal (26.8%) and heptanal (13.7%) in the oil of L. sciuroides. The essential oil of H. splendens was rich in monoterpenes (30.8%), and aldehydes (49.9%) were the major constituents in the oil …

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Potentiometric Determination Of Some Food Additives And Their Binding To A Polycationic Species Using Polyion Sensors, Nedi̇me Dürüst, Ali̇ Kayansalan Jan 2013

Potentiometric Determination Of Some Food Additives And Their Binding To A Polycationic Species Using Polyion Sensors, Nedi̇me Dürüst, Ali̇ Kayansalan

Turkish Journal of Chemistry

Polycation-sensitive membrane electrodes based on dinonylnaphthalene sulfonate (DNNS) were examined for the determination of some polyanions, namely xanthan (Xanth), alginate (Alg), carboxymethyl cellulose (CMC), and carrageenan (Carr). The potentiometric titrations of polyanionic analytes yielded sharp end points and correlative stoichiometries. After the determinations were successfully performed in saline, these polyanions were also determined in some food products consumed in Bolu (Turkey). In addition, the titration data were used to estimate the interactions between titrant and polyanionic analytes. The equilibrium constants, K_{eq}, and the number of titrant binding sites (n) per mole of analyte polyanion were calculated using Scatchard plots. The …

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Application Of Experimental Design On Determination Of Aluminum Content In Saline Samples By Adsorptive Cathodic Stripping Voltammetry, Si̇nan Yilmaz, Betül Öztürk, Durmuş Özdemi̇r, Ahmet Emi̇n Eroğlu, Fatma Ni̇l Ertaş Jan 2013

Application Of Experimental Design On Determination Of Aluminum Content In Saline Samples By Adsorptive Cathodic Stripping Voltammetry, Si̇nan Yilmaz, Betül Öztürk, Durmuş Özdemi̇r, Ahmet Emi̇n Eroğlu, Fatma Ni̇l Ertaş

Turkish Journal of Chemistry

Adsorptive cathodic stripping voltammetric determination of aluminum at ng mL^{-1} levels in salt samples based on the metal complexation with Calcon (1-(2-hydroxynaphthylazo)-2 naphthol-4-sulfonic acid) and the subsequent adsorptive deposition onto a hanging mercury drop electrode was studied. Central composite design was used as a design method. Several chemical and instrumental parameters (pH, ligand concentration, deposition time, deposition potential, and complexing time) were involved in the experimental design. Analytical parameters such as repeatability, linearity, and accuracy were also investigated and the detection limit was found as 0.32 ng mL^{-1}.

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Study On Crystal Transformation Process Of Magnesium Carbonate Hydrate Based On Salt Lake Magnesium Resource Utilization, Juan Du, Zhen Chen, Yulong Wu, Mingde Yang, Jie Dang, Jianjun Yuan Jan 2013

Study On Crystal Transformation Process Of Magnesium Carbonate Hydrate Based On Salt Lake Magnesium Resource Utilization, Juan Du, Zhen Chen, Yulong Wu, Mingde Yang, Jie Dang, Jianjun Yuan

Turkish Journal of Chemistry

The crystal transformation process of magnesium carbonate hydrate by the reaction of magnesium sulfate (MgSO_4) with ammonium carbonate [(NH_4)_2CO_3] was investigated. MgSO_4 is one of the main magnesium resources of the Lop Nur salt lake in the Xinjiang Autonomous Region of China. Magnesium carbonate hydrates with different chemical compositions were prepared. The transformation process of the 2 crystals, MgSO_4 and (NH_4)_2CO_3, was analyzed by Raman spectroscopy, and the associated changes in crystal morphology were observed by scanning electron microscopy. The needle-like MgCO_3 \cdot 3H_2O transformed into sheet-like 4MgCO_3 \cdot Mg(OH)_2 \cdot 4H_2O when the temperature was increased from 323 K …

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Development And Deployment Of A Point-Source Digital Inline Holographic Microscope For The Study Of Plankton And Particles To A Depth Of 6000 M, Alexander B. Bochdansky, Manfred H. Jericho, Gerhard J. Herndl Jan 2013

Development And Deployment Of A Point-Source Digital Inline Holographic Microscope For The Study Of Plankton And Particles To A Depth Of 6000 M, Alexander B. Bochdansky, Manfred H. Jericho, Gerhard J. Herndl

OES Faculty Publications

Bochdansky, A. B., Jericho, M. H., & Herndl, G. J. (2013). Development and deployment of a point-source digital inline holographic microscope for the study of plankton and particles to a depth of 6000 m. Limnology and Oceanography: Methods, 11, 28-40. doi: 10.4319/lom.2013.11.28

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