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2011

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Articles 16111 - 16140 of 17310

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Directional Limits On Persistent Gravitational Waves Using Ligo S5 Science Data, J. Abadie, B. P. Abbott, Matthew Benacquista, Teviet Creighton, R. Grosso, J. Li, Soma Mukherjee, Soumya Mohanty, Malik Rakhmanov, Volker Quetschke, Robert Stone, Joseph D. Romano, B. Vaishnav Jan 2011

Directional Limits On Persistent Gravitational Waves Using Ligo S5 Science Data, J. Abadie, B. P. Abbott, Matthew Benacquista, Teviet Creighton, R. Grosso, J. Li, Soma Mukherjee, Soumya Mohanty, Malik Rakhmanov, Volker Quetschke, Robert Stone, Joseph D. Romano, B. Vaishnav

Physics & Astronomy Faculty Publications

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2−20×10−50  strain2 Hz−1 and 5−35×10−49  strain2 Hz−1 sr−1 for pointlike and extended sources, respectively. The latter result is the first of its kind. We also set 90% C.L. limits on the narrow-band root-mean-square GW …

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Magnetization Precession And Domain-Wall Structure In Cobalt-Ruthenium-Cobalt Trilayers, Zhen Li, Ralph Skomski, Sy-Hwang Liou, Steven Michalski, Mircea Chipara, Roger D. Kirby Jan 2011

Magnetization Precession And Domain-Wall Structure In Cobalt-Ruthenium-Cobalt Trilayers, Zhen Li, Ralph Skomski, Sy-Hwang Liou, Steven Michalski, Mircea Chipara, Roger D. Kirby

Physics & Astronomy Faculty Publications

The magnetization dynamics of Co(5 nm)/Ru/Co(5 nm) trilayers with Ru thicknesses from 0.3–0.6 nm is experimentally and theoretically investigated. The coupling between the Co layers is antiferromagnetic (AFM) and yields a stable AFM domain structure with frozen domain walls. Comparing high-resolution magnetic force microscopy (MFM) and pump-probe measurements, we analyze the behavior of the films for different field-strength regimes. For moderate magnetic fields, pump-probe measurements provide dynamic characterization of the coupled precessional modes in the GHz range. The dynamics at small fields is realized by the pinning of AFM domain walls at inhomogeneities. The MFM images yield a domain-wall width …

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Magnetization Precession And Domainwall Structure In Cobalt-Ruthenium-Cobalt Trilayers, Zhen Li, Ralph Skomski, Sy-Hwang Liou, Steven Michalski, Mircea Chipara, Roger D. Kirby Jan 2011

Magnetization Precession And Domainwall Structure In Cobalt-Ruthenium-Cobalt Trilayers, Zhen Li, Ralph Skomski, Sy-Hwang Liou, Steven Michalski, Mircea Chipara, Roger D. Kirby

Physics & Astronomy Faculty Publications

The magnetization dynamics of Co(5 nm)/Ru/Co(5 nm) trilayers with Ru thicknesses from 0.3–0.6 nm is experimentally and theoretically investigated. The coupling between the Co layers is antiferromagnetic (AFM) and yields a stable AFM domain structure with frozen domain walls. Comparing high-resolution magnetic force microscopy (MFM) and pump-probe measurements, we analyze the behavior of the films for different field-strength regimes. For moderate magnetic fields, pump-probe measurements provide dynamic characterization of the coupled precessional modes in the GHz range. The dynamics at small fields is realized by the pinning of AFM domain walls at inhomogeneities. The MFM images yield a domain-wall width …

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Teaching Introductory Undergraduate Physics Using Commercial Video Games, Soumya Mohanty, Sergio Cantu Jan 2011

Teaching Introductory Undergraduate Physics Using Commercial Video Games, Soumya Mohanty, Sergio Cantu

Physics & Astronomy Faculty Publications

Commercial video games are increasingly using sophisticated physics simulations to create a more immersive experience for players. This also makes them a powerful tool for engaging students in learning physics. We provide some examples to show how commercial off-the-shelf games can be used to teach specific topics in introductory undergraduate physics. The examples are selected from a course taught predominantly through the medium of commercial video games.

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Predicted Ultrafast Dynamic Metallization Of Dielectric Nanofilms By Strong Single-Cycle Optical Fields, Maxim Durach, Anastasia Rusina, Matthias F. Kling, Mark I. Stockman Jan 2011

Predicted Ultrafast Dynamic Metallization Of Dielectric Nanofilms By Strong Single-Cycle Optical Fields, Maxim Durach, Anastasia Rusina, Matthias F. Kling, Mark I. Stockman

Physics & Astronomy: Faculty Publications

We predict a dynamic metallization effect where an ultrafast (single-cycle) optical pulse with a ≲1  V/Åfield causes plasmonic metal-like behavior of a dielectric film with a few-nm thickness. This manifests itself in plasmonic oscillations of polarization and a significant population of the conduction band evolving on a ∼1  fs time scale. These phenomena are due to a combination of both adiabatic (reversible) and diabatic (for practical purposes irreversible) pathways.

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Behavioral Momentum Theory: Equations And Applications, John A. Nevin, Timothy A. Shahan Jan 2011

Behavioral Momentum Theory: Equations And Applications, John A. Nevin, Timothy A. Shahan

Psychology Faculty Publications

Behavioral momentum theory provides a quantitative account of how reinforcers experienced within a discriminative stimulus context govern the persistence of behavior that occurs in that context. The theory suggests that all reinforcers obtained in the presence of a discriminative stimulus increase resistance to change, regardless of whether those reinforcers are contingent on the target behavior, are noncontingent, or are even contingent on an alternative behavior. In this paper, we describe the equations that constitute the theory and address their application to issues of particular importance in applied settings. The theory provides a framework within which to consider the effects of …

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Design Of Superconducting Parallel-Bar Deflecting/Crabbing Cavities With Improved Properties, Jean R. Delayen, Subashini De Silva Jan 2011

Design Of Superconducting Parallel-Bar Deflecting/Crabbing Cavities With Improved Properties, Jean R. Delayen, Subashini De Silva

Physics Faculty Publications

The superconducting parallel-bar cavity is a deflecting/crabbing cavity with attractive properties, compared to other conventional designs, that is being considered for a number of applications. All designs to-date have been based on straight loading elements and rectangular outer conductors. We present new designs of parallel-bar cavities using curved loading elements and circular or elliptical outer conductors, with significantly improved properties such as reduced surface fields and wider higher-order mode separation.

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Synthesis Of Some 2,3,6,8-Tetraarylimidazo[1,2-A]Pyrazine Derivatives By Using Either Reflux Or Microwave Irradiation Method, And Investigation Their Anticancer Activities, İsmai̇l Kayaği̇l, Şeref Demi̇rayak Jan 2011

Synthesis Of Some 2,3,6,8-Tetraarylimidazo[1,2-A]Pyrazine Derivatives By Using Either Reflux Or Microwave Irradiation Method, And Investigation Their Anticancer Activities, İsmai̇l Kayaği̇l, Şeref Demi̇rayak

Turkish Journal of Chemistry

In this study, some 2,3,6,8-tetraarylimidazo[1,2-a]pyrazine derivatives were synthesized by reacting 1-(2-aryl-2-oxoethyl)-2-aryloyl-4,5-diarylimidazoles from 2-aryloyl-4,5-diarylimidazole and 2-bromoacetophenone derivatives with ammonium acetate in acetic acid by using the method that was previously developed and repeatedly tested in our studies. Structural elucidation of the compounds was performed by IR, ^1H-NMR, and MASS spectroscopic data and elemental analysis results. Anticancer activities of selected compounds were evaluated and the noticeable activity values were reported.

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Simultaneous Determination Of Trace Sn(Ii) And Sn(Iv) Using Differential Pulse Polarography And Application, Güler Somer, Ülkü Ünal Jan 2011

Simultaneous Determination Of Trace Sn(Ii) And Sn(Iv) Using Differential Pulse Polarography And Application, Güler Somer, Ülkü Ünal

Turkish Journal of Chemistry

A new method was established for the simultaneous determination of Sn(II) and Sn(IV) using differential pulse polarography (DPP). Among several electrolytes, 0.1 M NaOH in the presence of 0.1 M KNO_3 was found to be the most suitable one. In this medium, Sn(II) had 2 peaks, at -0.74 and -1.17 V, which were sharp and very sensitive. Sn(IV), on the other hand, had a very small peak at -0.92 V when its concentration was higher than 4.0 \times 10^{-4} M. Thus, it was decided to determine Sn(IV) after reduction into Sn(II). In the presence of both Sn(II) and Sn(IV), Sn(II) …

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Reaction Of Cycloheptatriene Derivatives With 1,3-Diketones In The Presence Of Mn(Oac)_3, Mahi̇r Burak Südemen, Mustafa Zengi̇n, Hayri̇ye Genç, Meti̇n Balci Jan 2011

Reaction Of Cycloheptatriene Derivatives With 1,3-Diketones In The Presence Of Mn(Oac)_3, Mahi̇r Burak Südemen, Mustafa Zengi̇n, Hayri̇ye Genç, Meti̇n Balci

Turkish Journal of Chemistry

The reactions of some 1,3-dicarbonyl compounds with cycloheptatriene derivatives in the presence of Mn(OAc)_3 were examined. Cycloheptatriene forms mainly [2+3] and [6+3] dihydrofuran addition products derived from cycloheptatriene. However, the reaction of acetylacetone with cycloheptatriene substituted with an electron withdrawing group exclusively gave products derived from the norcaradiene structure. The formation mechanism of the products as well as the role of the substituent attached to cycloheptatriene is discussed.

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Effect Of Cmc And Hpc Mixture On The Photocatalytic Activity Of Nd-Tio_2/Sio_2 Film Under Visible Light Irradiation, Parviz Aberoomand, Shahram Moradi, Susan Samadi, Mohammad Saber Tehrani, Mohammad Hadi Givianrad Jan 2011

Effect Of Cmc And Hpc Mixture On The Photocatalytic Activity Of Nd-Tio_2/Sio_2 Film Under Visible Light Irradiation, Parviz Aberoomand, Shahram Moradi, Susan Samadi, Mohammad Saber Tehrani, Mohammad Hadi Givianrad

Turkish Journal of Chemistry

Neodymium-titania/silica films were prepared by the sol-gel method with the addition of various amounts of hydroxy propyl cellulose (HPC) and 5.09 \times 10^{-5} g g^{-1}_{solution} of carboxy methyl cellulose (CMC) in saturated conditions. The porous Nd-TiO_2/SiO_2 was obtained after heat treatment for 2 h at 500 °C, with the surface area up to 276 m^2 g^{-1}, which was measured using the Brunauer, Emmett, and Teller (BET) method. Scanning electron microscopy (SEM) showed that the particle size of Nd-TiO_2/SiO_2 decreased and the microstructure of the film became loose in suitable conditions with the addition of CMC to HPC. Subsequently, the photocatalytic …

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Azocalixarenes.7: Synthesis And Study Of The Absorption Properties Of Novel Mono-Azo Substituted Chromogenic Calix[4]Arenes, Hasaletti̇n Deli̇göz, Özlem Özen Karakuş Jan 2011

Azocalixarenes.7: Synthesis And Study Of The Absorption Properties Of Novel Mono-Azo Substituted Chromogenic Calix[4]Arenes, Hasaletti̇n Deli̇göz, Özlem Özen Karakuş

Turkish Journal of Chemistry

Eight new mono-azo substituted chromogenic calix[4]arenes (1-8) were synthesized by diazo-coupling reactions in which 25,26,27-tribenzoyloxy-28-hydroxy-5,11,17-tri-(tert-butyl)calix[4]arene and diazonium salts (2-, 3-, and 4-nitroaniline; 4-phenyl azoaniline; 3- and 4-chloroaniline; or 2- and 4-methylaniline) formed the corresponding mono-azo substituted derivatives in high yields. The mono-azo substituted calix[4]arenes were characterized by UV-Vis, FT-IR, and ^1H-NMR spectroscopic techniques. Elemental analysis was also carried out. In addition, the effects of varying pH levels and solvents upon the absorption ability of azocalix[4]arenes substituted with electron-donating and electron-withdrawing groups at their o-, m-, and p- positions were studied. The results proved that the absorption maxima of the prepared …

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Synthesis And Evaluation Of The Analgesic Activity Of Some New Isoxazolo[4,5-D]Pyridazin-4(5h)-One Derivatives, Oya Ünsal Tan, Keri̇man Özadali, Özgür Yeşi̇lyurt, Hakan Kayir, İsmai̇l Tayfun Uzbay, Ayla Balkan Jan 2011

Synthesis And Evaluation Of The Analgesic Activity Of Some New Isoxazolo[4,5-D]Pyridazin-4(5h)-One Derivatives, Oya Ünsal Tan, Keri̇man Özadali, Özgür Yeşi̇lyurt, Hakan Kayir, İsmai̇l Tayfun Uzbay, Ayla Balkan

Turkish Journal of Chemistry

Some isoxazolo[4,5-d]pyridazin4(5H)-one derivatives were synthesized and tested for their analgesic activity. The analgesic activities of the compounds were determined by hot-plate and acetic acid writhing tests using morphine and diclofenac as references. Compounds 4a, 4f, 4g, and 4i (25 mg/kg) showed analgesic profiles similar to that of morphine (5 mg/kg).

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Antimicrobial Activity And Volatile Constituents Of The Flower, Leaf, And Stem Of Paeonia Daurica Grown In Turkey, Gonca Tosun, Nuran Kahri̇man, Canan Albay, Şengül Alpay Karaoğlu, Nuretti̇n Yayli Jan 2011

Antimicrobial Activity And Volatile Constituents Of The Flower, Leaf, And Stem Of Paeonia Daurica Grown In Turkey, Gonca Tosun, Nuran Kahri̇man, Canan Albay, Şengül Alpay Karaoğlu, Nuretti̇n Yayli

Turkish Journal of Chemistry

The volatile constituents of the essential oils from the flower, leaf, and stem of Paeonia daurica Andrews were analyzed by GC and GC-MS. A total of 74 compounds were identified, constituting over 95.0%, 80.8%, and 98.2% of the oil composition of the flower, leaf, and stem of P. daurica, respectively. Aldehydes were shown to be the main group of constituents of the flower and stem parts, at 39.1% and 79.8%, respectively. However, the major group in the leaf oil was found to be oxygenated monoterpenes (43.5%). Salicylaldehyde (20.7% and 79.5%) was the major component of the flower and stem oils …

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Enantioselective Complexation Of Chiral Lariat Crown Ethers And Chiral Primary Alkylammonium Perchlorates, Mehmet Zafer Köylü, Tarik Aral, Mehmet Karakaplan, Şafak Özhan Kocakaya, Hali̇l Hoşgören Jan 2011

Enantioselective Complexation Of Chiral Lariat Crown Ethers And Chiral Primary Alkylammonium Perchlorates, Mehmet Zafer Köylü, Tarik Aral, Mehmet Karakaplan, Şafak Özhan Kocakaya, Hali̇l Hoşgören

Turkish Journal of Chemistry

In order to investigate the enantiomeric recognition abilities toward 2 chiral alkylammonium perchlorates (AmI, AmII) by ^1H-NMR titration method in CDCl_3, 4 chiral lariat ethers 8-11 with a (p-methoxyphenoxy) methyl flexible side arm were used. The most effective enantiomeric recognition was obtained by LCEs 9 and 11 toward AmII, by K_R/K_S 6.58 and K_S/K_R 6.63, respectively. The effect of macroring size, subunit of macroring, and side arm appeared to have strong influence on the binding ability of these alkylammonium ions.

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Controlled Growth Of Two-Dimensional Copper Nanoplates In Graphite Gallery, Xiaobei Bin, Jiazang Chen, Hong Cao Jan 2011

Controlled Growth Of Two-Dimensional Copper Nanoplates In Graphite Gallery, Xiaobei Bin, Jiazang Chen, Hong Cao

Turkish Journal of Chemistry

Copper nanoplates embedded in a graphite gallery were obtained by in situ reduction of stage 1, stage 2, and stage 3 CuCl_2-graphite intercalation compound precursors. The characterization results indicated that the morphology of the copper species was that of a 2-dimensional or quasi-2-dimensional nanoplate in the graphite gallery. Interaction between the metallic nanoplates and graphene sheet was also detected. The hexagonal graphene network restricted the crystallization orientation of the copper nanoparticles, and, at the same time, the finite space between the graphene sheets prevented the increase of the thickness. This method would provide a convenient route to synthesize or assemble …

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Polarographic Determination Of Anticancer Drug Vitamin K_3 With Direct And Indirect Methods/Application To Serum And K_3 Injection Solution, Ümmi̇han Taşkoparan Yilmaz, Güler Somer Jan 2011

Polarographic Determination Of Anticancer Drug Vitamin K_3 With Direct And Indirect Methods/Application To Serum And K_3 Injection Solution, Ümmi̇han Taşkoparan Yilmaz, Güler Somer

Turkish Journal of Chemistry

In this work, direct and indirect methods for determination of vitamin K_3 were developed using differential pulse polarography. The reaction between sulfite and the quinone (Q) form of vitamin K_3 was used for indirect determination, since the sulfite peak at -0.7 V is sharp and very reproducible in 0.1 M HAc NaAc (pH = 5.5). It was found that at pH 4.5-5.5, this reaction was quantitative and very fast when the temperature was 45 °C. For its direct determination, on the other hand, vitamin K_3 was standardized by the indirect method using standard sulfite as the reducing agent. The calibration …

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Determination Of Stability Constants Of 5-(2-Hydroxybenzylidene)-2-Thioxodihydropyrimidine-4,6(1h,5h)-Dione With Copper(Ii) And Mercury(Ii) Ions, Morteza Bahram, Nader Noroozi Pesyan, Abdolhossein Naseri, Masomeh Tasbihforosh Jan 2011

Determination Of Stability Constants Of 5-(2-Hydroxybenzylidene)-2-Thioxodihydropyrimidine-4,6(1h,5h)-Dione With Copper(Ii) And Mercury(Ii) Ions, Morteza Bahram, Nader Noroozi Pesyan, Abdolhossein Naseri, Masomeh Tasbihforosh

Turkish Journal of Chemistry

In this work, a hard model chemometric method was used to determine the stability constants of copper(II) and mercury(II) complexes with the newly synthesized ligand 5-(2-hydroxybenzylidene)- 2-thioxodihydropyrimidine-4,6(1H,5H)-dione in acetonitrile by UV-Vis spectrophotometry. The ligand forms stable complexes with both metal cations. The protonation constants of the ligand were also measured in an ethanol-water (1:1) mixture.

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Synthesis, Crystal Structure, And Antioxidant Properties Of Novel 1,2,4-Triazol-5-Ones Containing 3,4-Dimethoxyphenyl And 3,4-Dihydroxyphenyl Moiety, Yasemi̇n Ünver, Sevgi̇ Meydanal, Kemal Sancak, Di̇lek Ünlüer, Reşat Ustabaş, Esra Düğdü Jan 2011

Synthesis, Crystal Structure, And Antioxidant Properties Of Novel 1,2,4-Triazol-5-Ones Containing 3,4-Dimethoxyphenyl And 3,4-Dihydroxyphenyl Moiety, Yasemi̇n Ünver, Sevgi̇ Meydanal, Kemal Sancak, Di̇lek Ünlüer, Reşat Ustabaş, Esra Düğdü

Turkish Journal of Chemistry

A series of new 4-(3,4-dimethoxyphenethyl)-5-akyl/aryl-2H- 1,2,4-triazol-3(4H)-ones (3a-g) was obtained by the reaction of ethyl 2-(ethoxy)(alkylidene/arylidene)hydrazinecarboxylate (1) and 2-(3,4-dimethoxyphen- yl)ethanamine (2). Compounds 4a-f and 5 were synthesized from the reaction of corresponding compounds 3a-f and 3g with BBr_3, respectively. With elemental analysis, IR, ^1H-NMR, and ^{13C-NMR spectral data, 14 newly synthesized compounds were characterized. The structure of compound 3a was inferred through IR, ^1H- and ^{13}C-NMR, elemental analysis, and X-ray spectral techniques. In addition, the newly synthesized chemicals were screened for their antioxidant properties. Among the chemicals tested, 4a, 4c, 4d, 4f, and 5 exhibited the highest degree of antioxidant activity.

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Synthesis And Spectral Characterization Of A Decavanadate/Chitosan Complex, Violeta Dimitrova Kassabova Zhetcheva, Lilyana Parvanova Pavlova Jan 2011

Synthesis And Spectral Characterization Of A Decavanadate/Chitosan Complex, Violeta Dimitrova Kassabova Zhetcheva, Lilyana Parvanova Pavlova

Turkish Journal of Chemistry

A decavanadate/chitosan complex was synthesized by crosslinking chitosan with decavanadate anions at a pH of 3. The materials were characterized by Fourier transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), absorption spectroscopy (UV-Vis), and transmission electron microscopy (TEM). The spectroscopic results indicated that the decavanadate/chitosan complex was successfully obtained as result of an ionic crosslinking of the chitosan with decavanadate anions.

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Molecular Modeling And Antimycobacterial Studies Of Mannich Bases: 5-Hydroxy-2-Methyl-4h-Pyran-4-Ones, Barkin Berk, Demet Us, Si̇nem Öktem, Zühtü Tanil Kocagöz, Berrak Çağlayan, Işil Aksan Kurnaz, Di̇lek Demi̇r Erol Jan 2011

Molecular Modeling And Antimycobacterial Studies Of Mannich Bases: 5-Hydroxy-2-Methyl-4h-Pyran-4-Ones, Barkin Berk, Demet Us, Si̇nem Öktem, Zühtü Tanil Kocagöz, Berrak Çağlayan, Işil Aksan Kurnaz, Di̇lek Demi̇r Erol

Turkish Journal of Chemistry

The World Health Organization lists tuberculosis among the top 3 leading causes of death from a single infectious agent, and reported cases of multidrug-resistant tuberculosis (MDR-TB) are on the rise. In an attempt to improve MDR-TB drug-directed therapy, we synthesized 11 4-substituted piperazine derivatives of 3-hydroxy-6-methyl-4H-pyran-4-one pharmacophore by reacting 5-hydroxy-2-methyl-4H-pyran-4-one with suitable piperazine derivatives under Mannich reaction conditions. Inhibitory effects of the 11 compounds on Escherichia coli DNA gyrase were evaluated via DNA gyrase supercoiling assay. The minimum inhibitory concentrations (MIC) of the 11 compounds and 41 compounds from our previous studies against Mycobacterium tuberculosis H37RV were assessed, in vitro, …

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Preparation, Morphology, And Thermomechanical Properties Of Coal Ash/Polyethylene Oxide Composites, Khalid Saeed, Muhmmad Ishaq, Muhmmad Ilyas Jan 2011

Preparation, Morphology, And Thermomechanical Properties Of Coal Ash/Polyethylene Oxide Composites, Khalid Saeed, Muhmmad Ishaq, Muhmmad Ilyas

Turkish Journal of Chemistry

Coal ash/polyethylene oxide (ash/PEO) composite films were prepared by the solution casting technique. Scanning electron microscopy (SEM) micrographs indicated that the ash particles were dispersed and embedded well within the polymer matrix. The size of the ash particles in the PEO matrix was less than 3 \mu m. The polarized optical microscopic (POM) analyses revealed that the pure PEO, upon crystallization, showed distinct crystalline spherulites of a considerable size. The size of the spherulites was decreased by the incorporation of ash particles into the polymer matrix, which might be due to the nucleation role of ash in ash/PEO composite, and …

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Synthesis And Properties Of New Optically Active And Organosoluble Poly(Ester-Imide)S Containing L-Valine Moieties In The Main Chain By Direct Polycondensation Reaction, Khalil Faghihi, Meisam Shabanian, Mohsen Hajibeygi Jan 2011

Synthesis And Properties Of New Optically Active And Organosoluble Poly(Ester-Imide)S Containing L-Valine Moieties In The Main Chain By Direct Polycondensation Reaction, Khalil Faghihi, Meisam Shabanian, Mohsen Hajibeygi

Turkish Journal of Chemistry

New optically active poly(ester-imide)s (PEIs) containing bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic diimide in the main chain were prepared by the reaction of N,N'-(bicyclo[2,2,2]oct-7- ene-2,3,5,6-tetra carboxylic)-bis-L-valine 4 as a diacid monomer with various aromatic diols 5a-g in a system of tosyl chloride (TsCl), pyridine (Py), and N,N-dimethylformamide (DMF). The reactions with TsCl were significantly promoted by controlling alcoholysis with diols, in the presence of catalytic amounts of DMF, to give a series of optically active poly(ester-imide)s. The resulting new polymers were obtained in good yields and inherent viscosities, ranging between 0.36 and 0.62 dL g^{-1}, and were characterized with FT-IR and ^1H-NMR spectroscopy, including specific …

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E)--2--Acetyl--4--(4--Methoxyphenyldiazenyl) Phenol: X--Ray And Dft--Calculated Structure, Serap Yazici, Çi̇ğdem Albayrak, İsmai̇l Erdem Gümrükçüoğlu, İsmet Şenel, Orhan Büyükgüngör Jan 2011

E)--2--Acetyl--4--(4--Methoxyphenyldiazenyl) Phenol: X--Ray And Dft--Calculated Structure, Serap Yazici, Çi̇ğdem Albayrak, İsmai̇l Erdem Gümrükçüoğlu, İsmet Şenel, Orhan Büyükgüngör

Turkish Journal of Chemistry

The crystal structure of the title compound, (E)-2-acetyl-4-(4-methoxyphenyldiazenyl) phenol, displays a trans configuration of the azo moiety as found for other azo (diazene) derivatives. The aromatic mean planes are nearly coplanar and the dihedral angle between the 2 aromatic rings is 3.04(8)°. The molecules, with strong intramolecular O--H...O hydrogen bonding, are linked by weak van der Waals interactions in the 3-dimensional network. The molecular geometry, determined using X-ray diffraction techniques, was also calculated with the density functional theory (DFT), employing the hybrid exchange-correlation functional B3LYP. Experimental and theoretical IR spectra of the compound were also calculated for comparison. The results …

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Synthesis And Anti-Helicobacter Pylori Activity Of (4-Nitro-1-Imidazolylmethyl)-1,2,4-Triazoles, 1,3,4-Thiadiazoles, And 1,3,4-Oxadiazoles, Asal Fallah-Tafti, Tahmineh Akbarzadeh, Parastoo Saniee, Farideh Siavoshi, Abbas Shafiee, Alireza Foroumadi Jan 2011

Synthesis And Anti-Helicobacter Pylori Activity Of (4-Nitro-1-Imidazolylmethyl)-1,2,4-Triazoles, 1,3,4-Thiadiazoles, And 1,3,4-Oxadiazoles, Asal Fallah-Tafti, Tahmineh Akbarzadeh, Parastoo Saniee, Farideh Siavoshi, Abbas Shafiee, Alireza Foroumadi

Turkish Journal of Chemistry

A series of [(4-nitro-1H-imidazol-1-yl)methyl]-1,2,4- triazoles and 1,3,4-thiadiazoles were prepared and evaluated for their activity against sensitive and resistant H. pylori strains. Study of the structure-activity relationship of these series of compounds indicated that the type of nitroimidazole moiety and the pendent group on the heteroaryl analog dramatically impact the anti-H. pylori activity. In triazole series, compound 5d, containing a 4-methyl phenyl group on the triazole ring, was the most potent compound tested against both metronidazole-sensitive and -resistant strains at a concentration of 8 \mu g.

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Assimilable Organic Carbon Generation From Algogenic Organic Matter In Drinking Water, Ji-Hoon Kim, Young-Ju Kim, Tahir Imran Qureshi Jan 2011

Assimilable Organic Carbon Generation From Algogenic Organic Matter In Drinking Water, Ji-Hoon Kim, Young-Ju Kim, Tahir Imran Qureshi

Turkish Journal of Chemistry

A study of assimilable organic carbon (AOC) derived from algogenic organic matter in different drinking water resources was conducted. Seasonal changes in the concentration of AOC at Kamafusa Dam were dependent on the algal cell numbers. Variations in AOC concentrations were found to be more reliant on the AOC-P17 component than the AOC-NOX component. The algal culture experiment showed that extracellular organic matter (EOM) released during the growth of Phormidium tenue in M-11 culture medium led to a significant increase in AOC concentration; however, no significant variations of AOC concentration were observed in CT culture medium containing high amounts of …

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Synthesis And In Vitro Antimycobacterial Activities Of Novel 6-Substituted-3(2h)-Pyridazinone-2-Acetyl-2-(Substituted/ Nonsubstituted Acetophenone) Hydrazone, Semra Utku, Mehtap Gökçe, Gönül Aslan, Gül Bayram, Mahmut Ülger, Gürol Emekdaş, Mustafa Fethi̇ Şahi̇n Jan 2011

Synthesis And In Vitro Antimycobacterial Activities Of Novel 6-Substituted-3(2h)-Pyridazinone-2-Acetyl-2-(Substituted/ Nonsubstituted Acetophenone) Hydrazone, Semra Utku, Mehtap Gökçe, Gönül Aslan, Gül Bayram, Mahmut Ülger, Gürol Emekdaş, Mustafa Fethi̇ Şahi̇n

Turkish Journal of Chemistry

The difficulty in managing tuberculosis includes the prolonged duration of the treatment, the emergence of drug resistance, and coinfection with HIV/AIDS. Tuberculosis control requires new drugs that act on novel drug targets to help in combating resistant forms of Mycobacterium tuberculosis and reduce the treatment duration. For this purpose, 6-substituted-3(2H)-pyridazinone-2-acetyl-2- (substituted/nonsubstituted acetophenone) hydrazone derivatives were synthesized and their structures were elucidated by elemental analyses, IR, and ^1H-NMR. The in vitro antimycobacterial activities of synthesized compounds 5a-l were determined by the agar proportion method against Mycobacterium tuberculosis H37Rv. Among the target compounds, 5b and 5f exhibited the best antimycobacterial activity, with …

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Cover And Contents Jan 2011

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

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Zno Nanoflake Arrays Prepared Via Anodization And Their Performance In The Photodegradation Of Methyl Orange, Huey-Shya Goh, Rohana Adnan, Muhammad Akhyar Farrukh Jan 2011

Zno Nanoflake Arrays Prepared Via Anodization And Their Performance In The Photodegradation Of Methyl Orange, Huey-Shya Goh, Rohana Adnan, Muhammad Akhyar Farrukh

Turkish Journal of Chemistry

In the present work, anodization of zinc foil was investigated in a mixed electrolyte of ammonium sulfate and sodium hydroxide under the influence of different anodization times and concentrations of the electrolyte while the temperature and voltage were kept constant. The ZnO nanoflake arrays formed on Zn foil were characterized using a field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDX) analysis, and X-ray diffraction (XRD). The size of the nanoflakes increased as the anodization time increased, while increasing the concentration of (NH_4)_2SO_4 increased the dissolution of the nanoflakes. Upon stirring, the nanoflakes that formed were more uniform …

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One Pot Synthesis Of Pyridophenanthroline And Pyrrolophenanthroline Derivatives By Regioselective Reaction Between 1,7-Phenanthroline And Dialkyl Acetylenedicarboxylate: New Fused Heterocyclic Compounds, Malek Taher Maghsoodlou, Reza Heydari, Sayyed Mostafa Habibi Khorassani, Batool Tahami Pour, Ghasem Marandi, Farhad Maghfuri Jan 2011

One Pot Synthesis Of Pyridophenanthroline And Pyrrolophenanthroline Derivatives By Regioselective Reaction Between 1,7-Phenanthroline And Dialkyl Acetylenedicarboxylate: New Fused Heterocyclic Compounds, Malek Taher Maghsoodlou, Reza Heydari, Sayyed Mostafa Habibi Khorassani, Batool Tahami Pour, Ghasem Marandi, Farhad Maghfuri

Turkish Journal of Chemistry

1,7-Phenanthroline reacts with dialkyl acetylenedicarboxylate in a regioselective manner to give new macromolecules such as tetramethyl- 6aH-pyrido[1,2-i][1,7]phenanthroline-7,8,9,10-tetracarboxylate and trialkyl pyrrolo[1,2-i][1,7]phenanthroline-7,8,9-tricarboxylate derivatives.

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