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2012

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Articles 931 - 960 of 1111

Full-Text Articles in Chemistry

Cbe5e− (E = Al, Ga, In, Tl): Planar Pentacoordinate Carbon In Heptaatomic Clusters, Abril C. Castro, Gerarso Martinez-Guajardo, Thomas Johnson, Jesus M. Ugalde, Yan-Bo Wu, Jose M. Mercero, Thomas Heine, Kelling J. Donald, Gabriel Merino Jan 2012

Cbe5e− (E = Al, Ga, In, Tl): Planar Pentacoordinate Carbon In Heptaatomic Clusters, Abril C. Castro, Gerarso Martinez-Guajardo, Thomas Johnson, Jesus M. Ugalde, Yan-Bo Wu, Jose M. Mercero, Thomas Heine, Kelling J. Donald, Gabriel Merino

Chemistry Faculty Publications

A series of clusters with the general formula CBe5E- (E = Al, Ga, In, Tl) are theoretically shown to have a planar pentacoordinate carbon atom. The structures show a simple and rigid topological framework—a planar EBe4 ring surrounding a C center, with one of the ring Be–Be bonds capped in-plane by a fifth Be atom. The system is stabilized by a network of multicenter σ bonds in which the central C atom is the acceptor, and π systems as well by which the C atom donates charge to the Be and E atoms that encircle it.

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Resonant Inelastic X-Ray Scattering Of Methyl Chloride At The Chlorine K Edge, L. El Khoury, Loic Journel, Renaud Guillemin, Stephane Carniato, Wayne C. Stolte, T. Marin, Dennis W. Lindle, Marc Simon Jan 2012

Resonant Inelastic X-Ray Scattering Of Methyl Chloride At The Chlorine K Edge, L. El Khoury, Loic Journel, Renaud Guillemin, Stephane Carniato, Wayne C. Stolte, T. Marin, Dennis W. Lindle, Marc Simon

Chemistry and Biochemistry Faculty Research

We present a combined experimental and theoretical study of isolated CH3Cl molecules using resonant inelastic x-ray scattering (RIXS). The high-resolution spectra allow extraction of information about nuclear dynamics in the core-excited molecule. Polarization-resolved RIXS spectra exhibit linear dichroism in the spin-orbit intensities, a result interpreted as due to chemical environment and singlet-triplet exchange in the molecular core levels. From analysis of the polarization-resolved data, Cl 2px, y and 2pz electronic populations can be determined.

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Thomson-Resonant Interference Effects In Elastic X-Ray Scattering Near The Cl K Edge Of Hcl, Stephane Carniato, P. Selles, Loic Journel, Renaud Guillemin, Wayne C. Stolte, L. El Khoury, T. Marin, Faris Gel'mukhanov, Dennis W. Lindle, Marc Simon Jan 2012

Thomson-Resonant Interference Effects In Elastic X-Ray Scattering Near The Cl K Edge Of Hcl, Stephane Carniato, P. Selles, Loic Journel, Renaud Guillemin, Wayne C. Stolte, L. El Khoury, T. Marin, Faris Gel'mukhanov, Dennis W. Lindle, Marc Simon

Chemistry and Biochemistry Faculty Research

We experimentally observed interference effects in elastic x-ray scattering from gas-phase HCl in the vicinity of the Cl K edge. Comparison to theory identifies these effects as interference effects between non-resonant elastic Thomson scattering and resonant Raman scattering. The results indicate the non-resonant Thomson and resonant Raman contributions are of comparable strength. The measurements also exhibit strong polarization dependence, allowing an easy identification of the resonant and non-resonant contributions.

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Progress Towards A Facile Synthesis Of A Gadolinium (Iii) Octabrominated Porphyrin, Tseng Xiong Jan 2012

Progress Towards A Facile Synthesis Of A Gadolinium (Iii) Octabrominated Porphyrin, Tseng Xiong

The Corinthian

Towards preparing porphyrin complexes that combine contrast agent and photodynamic therapy capabilities at tumor sites, the Gd(III) porphyrin derivative of the octabrominated meso-tetrakis(N-methyl-4-pyridyl)porphyrin, GdTMPyPBr8 5+ was synthesized by refluxing Gd(III) ion with H3TMPyPBr8 5+ at pH 7. The metallocomplex was characterized by UV-visible spectroscopy and showed a Soret band shift from 503 nm to 463 nm at pH 7, suggesting that metal insertion of Gd(III) into the core of porphyrin ligand had occurred. However, synthesis of the Gd(III) complex required high temperatures and long reaction times. To circumvent these harsh conditions, the lithium porphyrin derivative was first prepared and subsequently …

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Ni_{55} Nanocluster: A Density Functional Theory Study Of The Binding Energy Of Nickel And Ethylene Adsorption, Nusret Duygu Yilmazer, Mehmet Ferdi̇ Fellah, Işik Önal Jan 2012

Ni_{55} Nanocluster: A Density Functional Theory Study Of The Binding Energy Of Nickel And Ethylene Adsorption, Nusret Duygu Yilmazer, Mehmet Ferdi̇ Fellah, Işik Önal

Turkish Journal of Chemistry

Ethylene adsorption on a Ni_{55} nanocluster was studied by means of the density functional theory (DFT)/B3LYP using the basis sets of 6-31G(d,p) and 86-411(41d)G in Gaussian 03. The Ni_{55} nanocluster was found to have a distorted icosahedral geometry, in accordance with the experimental findings. The binding energy value for the Ni_{55} nanocluster was calculated to be 3.51 eV/atom using equilibrium geometry calculations. The estimated bulk nickel binding energy was in reasonable agreement with the experimental value (4.85 versus 4.45 eV/atom). In addition, equilibrium geometry calculations were performed for ethylene adsorption on the Ni_{55} nanocluster for 2 different coordination numbers of …

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Synthesis And Characterization Of Transition Metal Coordination Polymers Derived From 1,4-Benzenedicarboxylate And Certain Azoles, Aref A. M. Aly, Mahmoud Ghandour, Maged S. Alfakeh Jan 2012

Synthesis And Characterization Of Transition Metal Coordination Polymers Derived From 1,4-Benzenedicarboxylate And Certain Azoles, Aref A. M. Aly, Mahmoud Ghandour, Maged S. Alfakeh

Turkish Journal of Chemistry

A series of coordination polymers of the general formula {[M(BDC)(azoles)(H_2O)_m].xH_2O}_n (where M = Co(II), Ni(II), and Cu(II); BDC = 1,4-benzenedicarboxylate; azoles = 2-aminobenzothiazole, 2-aminothiazole, and 2-amino-4-methyl-thiazole; m = 0 or 1; and x = 1 or 2) were prepared and characterized. The complexes were characterized based on elemental analysis, infrared and electronic spectral studies, magnetic measurements, molar conductance, thermal analysis, X-ray diffraction, scanning electron microscopy, and biological activity. Thermogravimetry, derivative thermogravimetry, and differential thermal analysis were used to study the thermal decomposition of the complexes. The kinetic parameters were calculated making use of the Coats-Redfern and Horowitz-Metzger equations.

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Four-Component Synthesis Of 1,3,4-Oxadiazole Derivatives From N-Isocyaniminotriphenylphosphorane, Aromatic Carboxylic Acids, Aromatic Bis-Aldehydes, And Secondary Amines, Ali Ramazani, Zahra Karimi, Ali Souldozi, Yavar Ahmadi Jan 2012

Four-Component Synthesis Of 1,3,4-Oxadiazole Derivatives From N-Isocyaniminotriphenylphosphorane, Aromatic Carboxylic Acids, Aromatic Bis-Aldehydes, And Secondary Amines, Ali Ramazani, Zahra Karimi, Ali Souldozi, Yavar Ahmadi

Turkish Journal of Chemistry

The 1:1 iminium intermediate generated by the addition of a secondary amine to aromatic bis-aldehydes (isophthalaldehyde and terphthalaldehyde) is trapped by the N-isocyaniminotriphenylphosphorane in the presence of a aromatic carboxylic acid derivative, which leads to the formation of corresponding iminophosphorane intermediate. Then disubstituted 1,3,4-oxadiazole derivatives are formed via intramolecular aza-Wittig reaction of the iminophosphorane intermediates. The reactions were completed in neutral conditions at room temperature and the corresponding disubstituted 1,3,4-oxadiazole derivatives were produced in excellent yields.

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Synthesis Of The Novel Benzothiazole Compounds From 7-Benzylidenebicyclo [3.2.0] Hept-2-En-6-Ones And 2-Aminobenzenethiol, Esra Findik Jan 2012

Synthesis Of The Novel Benzothiazole Compounds From 7-Benzylidenebicyclo [3.2.0] Hept-2-En-6-Ones And 2-Aminobenzenethiol, Esra Findik

Turkish Journal of Chemistry

Synthesis of the 2-(2-styrylcyclopent-3-enyl)benzo-[d]thiazoles (6a-i) is reported for the first time. Reaction of 7-benzylidenebicyclo [3.2.0] hept-2-en-6-ones (3a-i) and 2-aminobenzenethiol (4) in the presence of p-TsOH as a catalyst, in ethanol under reflux, resulted in the formation of novel 2-(2-styrylcyclopent-3-enyl)benzo[d]thiazoles in high yields.

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Synthesis Of \Alpha-Aminonitriles Catalyzed By Montmorillonite K10 In The Presence Of Dicationic Phosphonium Salt In Water Under Ultrasonic Effect, Çi̇ğdem Yildirim, Çi̇ğdem Yolaçan, Feray Aydoğan Jan 2012

Synthesis Of \Alpha-Aminonitriles Catalyzed By Montmorillonite K10 In The Presence Of Dicationic Phosphonium Salt In Water Under Ultrasonic Effect, Çi̇ğdem Yildirim, Çi̇ğdem Yolaçan, Feray Aydoğan

Turkish Journal of Chemistry

The synthesis of \alpha-aminonitriles was successfully accomplished by the 1-pot 3-component reaction of several aldehydes with (S)-\alpha-phenylethylamine and sodium cyanide in water in the presence of montmorillonite K10 and dicationic phosphonium salt under ultrasonic effect with good yields and moderate diastereoselectivities.

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A Dft Study On The Structural And Optical Properties And Cation Selectivities Of Some Metal-Coumarin-Crown Ether Complexes, Emi̇ne Esra Kasapbaşi, Mi̇ne Yurtsever Jan 2012

A Dft Study On The Structural And Optical Properties And Cation Selectivities Of Some Metal-Coumarin-Crown Ether Complexes, Emi̇ne Esra Kasapbaşi, Mi̇ne Yurtsever

Turkish Journal of Chemistry

Macrocyclic ethers are well-known molecules because of their high cation-binding capacities. They form stable complexes with alkaline and soil alkaline metals through strong oxygen bridges in solution. For enhanced optical properties, a new series of crown ethers was synthesized with a coumarin ring fused to it. The effects of the position of the coumarin ring, the type of the substituent on the coumarin ring, and the size of the crown on the optical properties of the material were studied according to the density functional theory (DFT) method at the B3LYP/6-31g(d) level of theory in the gas phase as well as …

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Theory Of Adsorption Equilibria Analysis Based On General Equilibrium Constant Expression, Abdul Sattar Ali Khan Jan 2012

Theory Of Adsorption Equilibria Analysis Based On General Equilibrium Constant Expression, Abdul Sattar Ali Khan

Turkish Journal of Chemistry

Adsorption equilibria were analyzed on the basis of general equilibrium constant expression for the development of fundamental adsorption equations (Freundlich, Langmuir, and BET) in connection with the establishment of a general approach towards physical interpretations of adsorption parameters. Theoretically it was proved that Freundlich plot analysis cannot be used to find useful parameters such as the monolayer adsorption capacity of an adsorbent. The present theory also indicated that the adsorption process with known value of monolayer adsorption capacity can be studied for finding various equilibrium constants on the basis of the Fronaeus equation, which is commonly used in the complexation …

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Synthesis And Antimicrobial Evaluation Of Some Annelated Phthalazine Derivatives And Acyclo C-Nucleosides From 1-Chloro-4-(2,4,6-Trimethylphenyl) Phthalazine Precursor, Maher Abdel Aziz El-Hashash, Ahmed Youssef Soliman, Ibrahim Essam Elshamy Jan 2012

Synthesis And Antimicrobial Evaluation Of Some Annelated Phthalazine Derivatives And Acyclo C-Nucleosides From 1-Chloro-4-(2,4,6-Trimethylphenyl) Phthalazine Precursor, Maher Abdel Aziz El-Hashash, Ahmed Youssef Soliman, Ibrahim Essam Elshamy

Turkish Journal of Chemistry

A highly efficient and versatile synthetic approach to the synthesis of annelated phthalazine derivatives viz. 1,2,4-triazolo [3,4-a]phthalazine 11a,b, 14, 18, 19a,b, 29-31, 33, 1,2,4-triazino [3,4-a]phthalazine 25a,b-28, 1,3,5-triazino[4,3-a]phthalazine 22, tetrazolo[5,1-a] phthalazine 23, imidazophthalazine 9a,b,15, and pyrimidinophthlazine 6, 10, 16, 17, 20 is presented. Moreover, acyclo C-nucleoside and double headed acyclo C-nucleoside of 1,2,4-triazolo[3,4-a]phthalazine 12, 13 were obtained via heterocyclization reaction of 1-chloro-4-(2,4,6-trimethylphenyl) phthalazine (4) with gluconic acid hydrazide and galactaric acid bis hydrazide, respectively. The new compounds were synthesized with the objective of studying their antimicrobial activity.

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Evaluation Of Thermodynamic Parameters Of Cadmium Adsorption On Sand From Temkin Adsorption Isotherm, Abdul Sattar Ali Khan Jan 2012

Evaluation Of Thermodynamic Parameters Of Cadmium Adsorption On Sand From Temkin Adsorption Isotherm, Abdul Sattar Ali Khan

Turkish Journal of Chemistry

Thermodynamic parameters provide clues for finding the spontaneity of a given process at a given temperature. In the present work, the Temkin adsorption model was applied for evaluation of the thermodynamic parameters of cadmium adsorption studied on sand. The lateral interaction energy parameter was found to be unity, which showed that the heat of adsorption is directly proportional to the fraction of free adsorption sites. The values of \Delta H° and \Delta S° were --4.8 kJ mol^{-1} and 42 J mol^{-1} K^{-1}, respectively. The value of \Delta G° was negative, indicating the spontaneity of cadmium adsorption on sand.

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Transmission Ft-Ir Spectroscopic Analysis Of Human Kidney Stones In The Hyderabad Region Of Pakistan, Muhammad Hussan Khaskheli, Syed Tufail Hussain Sherazi, Huma Mazhar Ujan, Sarfaraz Ahmed Mahesar Jan 2012

Transmission Ft-Ir Spectroscopic Analysis Of Human Kidney Stones In The Hyderabad Region Of Pakistan, Muhammad Hussan Khaskheli, Syed Tufail Hussain Sherazi, Huma Mazhar Ujan, Sarfaraz Ahmed Mahesar

Turkish Journal of Chemistry

The purpose of the present study was to investigate the composition of kidney stones removed from human patients. Seventeen samples were collected after surgery (5 females and 12 males; age range 2 to 60 years). The samples were analyzed for composition by transmission Fourier transform infrared (FT-IR) spectroscopy. The 17 analyzed samples of kidney stones comprised 29.4% calcium oxalate, 29.4% uric acid, 29.4% calcium oxalate (CaOx)-uric acid, 5.9% phosphate, and 5.9% calcium oxalate-phosphate stones. The results of the study indicated that transmission FT-IR spectroscopy could be used as an environmentally friendly technique for rapid screening of kidney stones.

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Synthetic Access To Benzazolyl (Pyrazoles, Thiazoles, Or Triazoles), Bakr Fathy Abdelwahab, Hanan Ahmed Mohamed Jan 2012

Synthetic Access To Benzazolyl (Pyrazoles, Thiazoles, Or Triazoles), Bakr Fathy Abdelwahab, Hanan Ahmed Mohamed

Turkish Journal of Chemistry

This review surveys data published in recent years on the synthesis of benzazoles linked directly with pyrazoles, thiazoles, or triazoles. Some of the commercial applications are mentioned.

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Functional Promiscuity Of The Cog0720 Family, Gabriela Phillips, Laura L. Grochowski, Shilah Bonnett, Huimin Xu, Marc Bailly, Crysten Haas-Blaby, Basma El Yacoubi, Dirk Iwata-Reuyl, Robert H. White, Valérie De Crécy-Lagard Jan 2012

Functional Promiscuity Of The Cog0720 Family, Gabriela Phillips, Laura L. Grochowski, Shilah Bonnett, Huimin Xu, Marc Bailly, Crysten Haas-Blaby, Basma El Yacoubi, Dirk Iwata-Reuyl, Robert H. White, Valérie De Crécy-Lagard

Chemistry Faculty Publications and Presentations

The biosynthesis of GTP derived metabolites such as tetrahydrofolate (THF), biopterin (BH4), and the modified tRNA nucleosides queuosine (Q) and archaeosine (G+) relies on several enzymes of the Tunnel-fold superfamily. A subset of these proteins include the 6-pyruvoyl-tetrahydropterin (PTPS-II), PTPS-III, and PTPS-I homologs, all members of the COG0720 family, that have been previously shown to transform 7,8-dihydroneopterin triphosphate (H2NTP) into different products. PTPS-II catalyzes the formation of 6-pyruvoyltetrahydropterin in the BH4 pathway. PTPS-III catalyzes the formation of 6-hydroxylmethyl-7,8-dihydropterin in the THF pathway. PTPS-I catalyzes the formation of 6-carboxy-5,6,7,8-tetrahydropterin in the Q pathway. Genes of these …

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Synthesis Of Linezolid-Like Molecules And Evaluation Of Their Antimicrobial Activities, Serap Başoğlu, Meltem Yolal, Ahmet Demi̇rbaş, Hakan Bektaş, Rza Abbasoğlu, Nesli̇han Demi̇rbaş Jan 2012

Synthesis Of Linezolid-Like Molecules And Evaluation Of Their Antimicrobial Activities, Serap Başoğlu, Meltem Yolal, Ahmet Demi̇rbaş, Hakan Bektaş, Rza Abbasoğlu, Nesli̇han Demi̇rbaş

Turkish Journal of Chemistry

3-Fluoro-4-(morpholin-4-yl)aniline (2), prepared from 3,4-difluoronitrobenzene, was converted to the corresponding Schiff base (3) by treatment with indol-3-carbaldehyde. The treatment of thiourea 4 and carbothioamide derivatives 9 with ethyl bromoacetate or 4-substituted phenacyl bromides generated the corresponding thiazolidinone (5 and 13) and thiazoline (6 and 12) derivatives, respectively. The acidic or basic treatment of carbothioamide 9 produced 1,3,4-thiadiazole (11) or 1,2,4-triazole (10) compounds, respectively. The structural assignments of the new compounds were based on elemental analysis and spectral (IR, ^1H-NMR, ^{13}C-NMR, and LC-MS) data. The antimicrobial activity study revealed that all compounds showed good antitubercular activities.

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Comparative Photodecolorization Of Red Dye By Anatase, Rutile (Tio_2), And Wurtzite (Zno) Using Response Surface Methodology, Shahab Khameneh Asl, Sayad Khatib Sadrnezaad, Mansour Keyanpour-Rad, Deni̇z Üner Jan 2012

Comparative Photodecolorization Of Red Dye By Anatase, Rutile (Tio_2), And Wurtzite (Zno) Using Response Surface Methodology, Shahab Khameneh Asl, Sayad Khatib Sadrnezaad, Mansour Keyanpour-Rad, Deni̇z Üner

Turkish Journal of Chemistry

Treatment of dye pollution containing C.I. Acid Red 14 (AR14) by a coupled photocatalytic process was studied. Titanium dioxide, in the form of anatase and rutile, and zinc oxide, were used as photocatalysts. The investigated photocatalysts were Aldrich-produced nanopowders with crystallites of a mean size of 20-30 nm and a specific surface area of about 50 m^2/g. A comparison of TiO_{2(anatase)}, TiO_{2(rutile)}, TiO_{2(a,r)}, and ZnO for the decolorization of the AR14 solution was performed. Results showed that color removal followed the decreasing order of TiO_{2(a,r)}, ZnO > TiO_{2(a,r)} > TiO_{2(a)}, ZnO > TiO_{2(r)}, ZnO >TiO_{2(a,r)} > TiO_{2(a)} > ZnO > TiO_{2(r)}. Response surface methodology (RSM) was …

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Synthesis, Characterization, And Antimicrobial Activity Of A New Pyrimidine Schiff Base And Its Cu(Ii), Ni(Ii), Co(Ii), Pt(Ii), And Pd(Ii) Complexes, Mehmet Gülcan, Mehmet Sönmez, İsmet Berber Jan 2012

Synthesis, Characterization, And Antimicrobial Activity Of A New Pyrimidine Schiff Base And Its Cu(Ii), Ni(Ii), Co(Ii), Pt(Ii), And Pd(Ii) Complexes, Mehmet Gülcan, Mehmet Sönmez, İsmet Berber

Turkish Journal of Chemistry

A new Schiff base, {1-[(5-bromo-2-hydroxy-benzylidene)- amino]-4-phenyl-2-thioxo-1,2-dihyro-pyrimidin-5-yl}-phenyl-methanone, was synthesized from N-amino pyrimidine-2-thione and 5-bromsalicylaldehyde. Metal complexes of the Schiff base were prepared from acetate salts of Cu(II), Ni(II), Co(II), Pd(II), and PtCl_2 in methanol. The chemical structures of the Schiff base ligand and its metal complexes were confirmed by spectroscopic analysis. All of the compounds were evaluated for their antimicrobial against 4 gram-positive bacteria, 1 gram-negative bacterium, and 3 yeast strains. The Schiff base and the Cu(II) and Co(II) complexes showed good biological activity against all tested bacteria and yeast strains.

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Polymers From Renewable Resources: Synthesis And Characterization Of Poly(2,5-Dihydro-2,5-Dimethoxy Furan), Hakan Çi̇ftçi̇, Zeki̇ Öktem, Hasan Nur Testereci̇ Jan 2012

Polymers From Renewable Resources: Synthesis And Characterization Of Poly(2,5-Dihydro-2,5-Dimethoxy Furan), Hakan Çi̇ftçi̇, Zeki̇ Öktem, Hasan Nur Testereci̇

Turkish Journal of Chemistry

The cationic polymerization of cis, trans-2,5-dihydro-2,5-dimethoxy furan (DHMF) was studied in the presence of HClO_4, in acetonitrile. Different reaction parameters were investigated such as initiator concentration and temperature with duration. Obtained polymers were soluble in dimethylsulfoxide (DMSO) and dimethylformamide (DMF) and the M_n value was calculated as 2700 g/mol by cryoscopy. The FT-IR and ^1H-NMR results indicate that the polymerization proceeds via ring opening. Thermal properties were studied by DSC and TGA.

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Influence Of Reaction Parameters On The Synthesis Of Surfactant-Assisted Tin Oxide Nanoparticles, Muhammad Akhyar Farrukh, Prisca Tan, Rohana Adnan Jan 2012

Influence Of Reaction Parameters On The Synthesis Of Surfactant-Assisted Tin Oxide Nanoparticles, Muhammad Akhyar Farrukh, Prisca Tan, Rohana Adnan

Turkish Journal of Chemistry

Tin oxide nanoparticles were synthesized via hydrothermal method using a non-ionic surfactant, oleyl amine (OLM), in the presence of urea. The reactions were carried out at different calcination temperatures and varying concentrations of surfactant and urea. The effect of these reaction parameters on the particles' size, distribution, surface area, and the average pore diameter were investigated using X-ray diffraction analysis, transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray analysis, thermogravimetric analysis, Brunauer-Emmett-Teller method, and Fourier transform infrared spectroscopy. Larger tin oxide nanoparticles were obtained with higher concentrations of urea. At the optimum experimental conditions, tin oxide nanoparticles with mean …

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Silica Nanoparticles As A High Efficient Catalyst For The One-Pot Synthesis Of 3-Oxo-3-Phenylpropanamid Derivatives From Isocyanides, Phenylacetaldehyde And Secondary Amines, Ali Ramazani, Kourosh Dastanra, Fatemeh Zeinali Nasrabadi, Zahra Karimi, Morteza Rouhani, Mehdi Hosseini Jan 2012

Silica Nanoparticles As A High Efficient Catalyst For The One-Pot Synthesis Of 3-Oxo-3-Phenylpropanamid Derivatives From Isocyanides, Phenylacetaldehyde And Secondary Amines, Ali Ramazani, Kourosh Dastanra, Fatemeh Zeinali Nasrabadi, Zahra Karimi, Morteza Rouhani, Mehdi Hosseini

Turkish Journal of Chemistry

Reaction of an isocyanide with an iminium ion intermediate, formed by reaction between 2-oxo-2-phenylacetaldehyde and a secondary amine in the presence of silica nanoparticles, proceeds smoothly at room temperature to afford ketoamide derivatives in high yields.

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Synthesis And Structural Characterization Of Novel Square Pyramidal Oxovanadium(Iv) Complexes With Ligands Having N And O Donor Atoms, Ashok Kumar Yadava, Hardeo Singh Yadav, Uma Shanker Yadav, Devendra Pratap Rao Jan 2012

Synthesis And Structural Characterization Of Novel Square Pyramidal Oxovanadium(Iv) Complexes With Ligands Having N And O Donor Atoms, Ashok Kumar Yadava, Hardeo Singh Yadav, Uma Shanker Yadav, Devendra Pratap Rao

Turkish Journal of Chemistry

Oxovanadium(IV) complexes having the general formula [VO(L)] were designed and synthesized using vanadyl ion as kinetic template with ligands derived by condensation of \beta-diketones such as acetylacetone, benzoylacetone, thenoyltrifluoroacetone, and dibenzoylmethane with 2-amino-3-hydroxypyridine or 2-aminobenzoic acid or 2-aminonicotinic acid. Tentative structures of the complexes were proposed on the basis of elemental analysis, molar conductance, magnetic moments, and spectral (infrared, electronic and electron spin resonance) data. All the oxovanadium(IV) complexes are 5-coordinated wherein derived ligands act as tetradentate chelating agents.

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A One-Pot Efficient Four-Component Reaction For The Synthesis Of 2-(Arylamino)-2-(5-Aryl-1-Ethenyl-1,3,4-Oxadiazol-2-Yl)Propyl Benzoate (Or 4-Bromobenzoate) Derivatives, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramov, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Fatemeh Zeinali Nasrabadi, Ali Souldozi Jan 2012

A One-Pot Efficient Four-Component Reaction For The Synthesis Of 2-(Arylamino)-2-(5-Aryl-1-Ethenyl-1,3,4-Oxadiazol-2-Yl)Propyl Benzoate (Or 4-Bromobenzoate) Derivatives, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramov, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Fatemeh Zeinali Nasrabadi, Ali Souldozi

Turkish Journal of Chemistry

Reactions of N-isocyaniminotriphenylphosphorane with 2-oxopropyl benzoate (or 2-oxopropyl 4-bromobenzoate) in the presence of 3-phenyl-2-propynoic acid and primary amines proceeded smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in high yields. The reaction proceeded smoothly and cleanly under mild conditions and no side reactions were observed.

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Synthesis And Antimicrobial Activity Of Some Novel 4-Hydroxyquinolin-2(1h)-Ones And Pyrano[3,2-C] Quinolinones From 3-(1-Ethy1-4-Hydroxy-2-Oxo-1,2-Dihydroquinolin-3-Yl)-3-Oxopropanoic Acid, Hany Mohamed Hassanin, Magdy Ahmed Ibrahim, Youssef Abdel-Salam Alnamer Jan 2012

Synthesis And Antimicrobial Activity Of Some Novel 4-Hydroxyquinolin-2(1h)-Ones And Pyrano[3,2-C] Quinolinones From 3-(1-Ethy1-4-Hydroxy-2-Oxo-1,2-Dihydroquinolin-3-Yl)-3-Oxopropanoic Acid, Hany Mohamed Hassanin, Magdy Ahmed Ibrahim, Youssef Abdel-Salam Alnamer

Turkish Journal of Chemistry

Chlorination, bromination, and condensation reactions of 3-(1-ethy1-4-hydroxy-2-oxo-1,2-dihydroquinolin-3-yl)-3-oxopropanoic acid (3) were studied. Some novel 4-hydroxyquinolin-2(1H)-ones and pyrano[3,2-c]quinolin-2(1H)-ones were also prepared. The structures of the novel compounds were established by elemental analyses and spectral data. All the products were also screened in vitro for their antimicrobial activity.

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Chemical And Biotransformation Of Gelomulide F: A Rare Diterpene Lactone, Humaira Yasmeen Gondal, Muhammad Iqbal Choudhary Jan 2012

Chemical And Biotransformation Of Gelomulide F: A Rare Diterpene Lactone, Humaira Yasmeen Gondal, Muhammad Iqbal Choudhary

Turkish Journal of Chemistry

Chemical and biotransformations of a rare diterpene lactone, Gelomulide F (1), from the cytotoxic extract of leaves of Suregada multiflora were studied. Fermentation of compound 1 with Sachromyces cerevisiae transformed it to Gelomulide D (2) and E (3), whereas its treatment with 2N KOH yielded Gelomulide D (2). In addition, a novel compound (4) was obtained by its diastereo and chemoselective reduction with NaBH_4. All of these compounds were characterized on the basis of extensive ^1H-NMR, ^{13}C-NMR, 2D NMR, and mass spectral analyses.

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Jones Seeks To Engage Students In Chemistry, Aldemaro Romero Jr. Jan 2012

Jones Seeks To Engage Students In Chemistry, Aldemaro Romero Jr.

Publications and Research

No abstract provided.

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Investigation Of Factors Influencing Trichloromethane Levels In Milk And Its Control., Siobhan Ryan Jan 2012

Investigation Of Factors Influencing Trichloromethane Levels In Milk And Its Control., Siobhan Ryan

Theses

Trichloromethane (TCM) is an undesirable chemical residue that can develop in milk. While TCM levels in milk are not within ranges of public health concern, it is important that minimal levels are maintained in order to promote the marketing of Irish dairy products abroad. Germany has enacted strict regulations on TCM concentrations in foodstuffs with a recommended level of0.002 mg/kg and re-analyse those milks, subsequent to cause identification and provision of advice on reducing TCM levels in milk. Milk samples were analysed using Gas chromatography (GC) with electron capture detection. The GC method was adapted and a standard curve was …

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Characterisation Of Crataegus Monogyna Fractions And Assessment Of Their Functional Properties, Eilish Shortle Jan 2012

Characterisation Of Crataegus Monogyna Fractions And Assessment Of Their Functional Properties, Eilish Shortle

Theses

Hawthorn {Crataegus monogyna) is a herb that has been used medicinally since ancient times. In modern medicine it is known for its cardiotonic properties and is used as a cardiovascular protective, hypotensive and hypocholesterolemic agent. In recent years supercritical fluid extraction (SFE) has become more popular as an extraction method for botanical material as it is an environmentally-friendly method that can produce toxic-free extracts. The optimal SFE extraction conditions for the extraction of antioxidant compounds from both, hawthorn leaf & dower and hawthorn berries, using carbon dioxide, were determined in this study. The optimized extracts were then compared to pre-prepared …

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Donor-Sigma-Acceptor (D-Sigma-A) Molecules With Perylenebisimide Acceptors Having Alkyl Or Peg Swallowtails With Sulfur Or Hydroxyl Anchors: Synthesis And Applications In Langmuir-Blodgett Films, Single Molecule Spectroscopy (Sms), G-Quadruplex Studies And Passivation Of Gold Nanoparticles, Rajesh Kota Jan 2012

Donor-Sigma-Acceptor (D-Sigma-A) Molecules With Perylenebisimide Acceptors Having Alkyl Or Peg Swallowtails With Sulfur Or Hydroxyl Anchors: Synthesis And Applications In Langmuir-Blodgett Films, Single Molecule Spectroscopy (Sms), G-Quadruplex Studies And Passivation Of Gold Nanoparticles, Rajesh Kota

Electronic Theses and Dissertations

Use of single molecules as electronic devices is presently considered a potential alternative to semiconductor-based nanoscale electronics. The ability to study a single molecule or a small group of molecules provides a great opportunity to build electronic devices at the molecular level. It is vital to understand the parameters that control the device properties such as molecular structure, conformation and arrangement at the surface. Ari Aviram and Mark A. Ratner proposed the construction of a single organic molecule as an organic rectifier. Donor-Sigma-Acceptor (D-?-A ) molecules, when arranged with a proper orientation as Langmuir-Blodgett (LB) films and fixed between two …

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