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2007

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Synthesis And Antimicrobial Activities Of Some New 1,2,4-Triazole Derivatives, Nurhan Gümrükçüoğlu, Mevlut Serdar, Eli̇f Çeli̇k, Ali̇ Sevi̇m, Nesli̇han Demi̇rbaş Jan 2007

Synthesis And Antimicrobial Activities Of Some New 1,2,4-Triazole Derivatives, Nurhan Gümrükçüoğlu, Mevlut Serdar, Eli̇f Çeli̇k, Ali̇ Sevi̇m, Nesli̇han Demi̇rbaş

Turkish Journal of Chemistry

A series of acylhydrazones (2a-f) were synthesized by the condensation of iminoester hydrochlorides (1a-f) with acyl hydrazines. 2,5-Dialkyl 1,3,4-oxadiazoles (3a,c,e) were obtained in the same reaction media. The treatment of acylhydrazones with hydrazine hydrate afforded 4-amino-3,5-dialkyl-1,2,4-triazoles (4a-c). The acetylation of 4-amino-3,5-dialkyl-1,2,4-triazoles produced N-[3,5-dialkyl-4H-1,2,4-triazol-4-yl] acetamides (5-7). The treatment of compounds 4a and 4c with various aromatic aldehydes resulted in the formation of 4-arylidenamino-3,5-dialkyl-1,2,4-triazoles (8a,d, e, and 10a-e). Sodium borohydride reduction of 4-arylidenamino derivatives afforded 4-alkylamino-3,5-dialkyl-1,2,4-triazoles (9a,d, e, and 11a-e). Compounds 4b, 4c, 7, 8d, and 11c showed good antifungal activity only against yeast-like fungi, while compounds 3e, 6, 8e, and 9e …

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New Diterpenoids From The Aerial Parts Of Salvia Pilifera, Ufuk Kolak Jan 2007

New Diterpenoids From The Aerial Parts Of Salvia Pilifera, Ufuk Kolak

Turkish Journal of Chemistry

Three new diterpenoids, piliferol (2\alpha, 20-dihydroxy-12-oxo- abieta-9(11),13-dien-8,20-ether) (1), salvipiliferol (2\alpha, 10\beta -dihydroxy-12-oxo-norabieta-9(11),13-dien) (2), and piliferalactone (2\alpha ,8-dihydroxy-12-oxo-abieta-9(11),13-dien-20-oic acid-8,20-lactone) (3), together with 7 known compounds, ursolic acid, oleanolic acid, betulinic acid, \alpha -amyrin, lupeol, \beta -sitosterol, and pectolinarigenin, have been isolated from the aerial parts of an endemic Salvia species, S. pilifera. Their structures were elucidated by spectral (UV, IR, 1D-, and 2D-NMR, and HRMS) methods.

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Speciation Of Manganese Using A Pneumatic Flow Injection Analysis-Tandem Spectrometer System, Meissam Noroozifar, Mozhgan Khorasani-Motlagh, Reza Akbari Jan 2007

Speciation Of Manganese Using A Pneumatic Flow Injection Analysis-Tandem Spectrometer System, Meissam Noroozifar, Mozhgan Khorasani-Motlagh, Reza Akbari

Turkish Journal of Chemistry

A pneumatic flow injection-tandem spectrometer system, without a delivery pump, was used for the speciation of manganese (Mn). In this system the suction force of the pneumatic nebulizer of a flame atomic absorption spectrometer (FAAS) was used for solution delivery through the manifold. Mn(VII) and total Mn (Mn(VII) and Mn(II)) concentrations were determined using a UV-Vis spectrometer and FAAS, respectively. The Mn(II) concentration was determined by the difference between the two. The calibration curves were linear up to 15.00 mg L^{-1} for Mn(VII) and total Mn, with a detection limit of 0.08 mg L^{-1} and 0.05 mg L^{-1} for Mn(VII) …

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Synthesis, Characterization, And Biocidal Studies Of The Newly Synthesized Di- And Triorganotin(Iv) Complexes With N-Butylhydrogen Phthalate, Sadiq-Ur Rehman, Saqib Ali, Saira Shahzadi, Abdul Malik, Ejaz Ahmed Jan 2007

Synthesis, Characterization, And Biocidal Studies Of The Newly Synthesized Di- And Triorganotin(Iv) Complexes With N-Butylhydrogen Phthalate, Sadiq-Ur Rehman, Saqib Ali, Saira Shahzadi, Abdul Malik, Ejaz Ahmed

Turkish Journal of Chemistry

Di-(1, 3, 8) and triorganotin(IV) complexes (2, 5, 7) with the general formula R_nSnL_{4-n}, where R = Me, Et, n-Bu, n-Oct, Ph, and Bz, and L = the n-C_4H_9OCOC_6H_4COO^- monoanionic ligand have been synthesized by the reaction of the silver salt of the n-butylhydrogen phthalate with di- and triorganotin chloride in dry chloroform. However, di-n-butyl- and di-n-octyltin(IV) derivatives (4 and 6, respectively) were synthesized by the reaction of the corresponding organotin(IV) oxide with n-butylhydrogen phthalate in dry toluene. All the synthesized complexes were characterized by elemental analysis, FT-IR, multinuclear (^1H, ^{13}C, ^{119}Sn) NMR, and mass spectrometric techniques to assess the …

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Synthesis Of Some New 1-Acylthiosemicarbazides And 1,2,4-Triazol-5-Thiones, And Their Analgesic And Anti-Inflammatory Activities, Yasemi̇n Dündar, Bi̇lge Çakir, Esra Küpeli̇, M. Fethi̇ Şahi̇n, Ni̇ngur Noyanalpan Jan 2007

Synthesis Of Some New 1-Acylthiosemicarbazides And 1,2,4-Triazol-5-Thiones, And Their Analgesic And Anti-Inflammatory Activities, Yasemi̇n Dündar, Bi̇lge Çakir, Esra Küpeli̇, M. Fethi̇ Şahi̇n, Ni̇ngur Noyanalpan

Turkish Journal of Chemistry

We synthesized new 1-[3-(2-oxobenzothiazolin-3-yl)propanoyl]-4- substituted-thiosemicarbazides and their corresponding cyclized 3-[2-(2-oxobenzothiazoline-3-yl)ethyl]-4-substituted-1,2,4-triazol-5-thione ana-logs in which position 4 of the triazole ring was substituted by cyclohexyl, methyl, allyl, phenyl, p-methylphenyl, p-methoxyphenyl, p-chlorophenyl, p-nitrophenyl, benzyl, and phenylethyl to screen their analgesic and anti-inflammatory activities as well as gastric ulceration potential in test animals. None of the compounds, except 5a, 5e, and 5h, caused gastric lesions or bleeding. Compound 5g was found to have higher analgesic and anti-inflammatory activity among the synthesized compounds.

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Benzimidazolylidene Carbene Ligated Palladium Catalysis Of The Heck Reaction In Aqueous Media, İsmai̇l Özdemi̇r, Yetki̇n Gök, Nevi̇n Gürbüz, Beki̇r Çeti̇nkaya Jan 2007

Benzimidazolylidene Carbene Ligated Palladium Catalysis Of The Heck Reaction In Aqueous Media, İsmai̇l Özdemi̇r, Yetki̇n Gök, Nevi̇n Gürbüz, Beki̇r Çeti̇nkaya

Turkish Journal of Chemistry

A highly effective, easy to handle and environmentally benign process for a palladium mediated Heck reaction was developed. The in situ prepared 3-component system, Pd(OAc)_2 / 1,3-dialkylbenzimidazolium chlorides (LHX = 1a-g) and Cs_2CO_3, catalyzes quantitatively the Heck coupling of aryl bromides under mild conditions in aqueous media.

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Role Of Tridentate Schiff Base And Methoxyethylindenyl Derivatives Of Lanthanocene Complexes For The Synthesis Of High Molecular Weight Polymethyl Methacrylate (Pmma), Muhammad Yousaf, Aftab Ahmad Chatha, Abdul Jabbar, H. Badaruddin Ahmad, Ameer Fawad Zahoor, Muhammad Kaleem Khosa, Syed Sarwar Alam Jan 2007

Role Of Tridentate Schiff Base And Methoxyethylindenyl Derivatives Of Lanthanocene Complexes For The Synthesis Of High Molecular Weight Polymethyl Methacrylate (Pmma), Muhammad Yousaf, Aftab Ahmad Chatha, Abdul Jabbar, H. Badaruddin Ahmad, Ameer Fawad Zahoor, Muhammad Kaleem Khosa, Syed Sarwar Alam

Turkish Journal of Chemistry

Different mixed ligand lanthanocene complexes along with Al(i-Bu)_3 are capable of synthesizing partially syndiotactic high molecular weight polymethylmethacrylate. The Schiff base derivative of mixed ligand lanthanocene complexes (1-4) showed better efficiency (Mv = 227 \times 10^3-354 \times 10^3) compared to the methoxyethylindenyl derivative of mixed ligand lanthanocene complexes (5-9) (Mv = 72 \times 10^3, 172 \times 10^3). The effects of the catalyst, temperature, catalyst/MMA molar ratio, and catalyst/Al(i-Bu)_3 molar ratio on the polymerization of MMA at 60 °C suggested that ligand size and radius of rare earth metals play an important role in determining the activity of the catalyst.

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N,N`-Bis(1`-Hydroxy-2`-Acetonaphthone)Propylenediamine: Synthesis, Extractive Properties, And Use As An Ionophore In A Cu(Ii)-Selective Potentiometric Sensor, Daryoush Emadi, Mohammad Reza Yaftian, Saeed Rayati Jan 2007

N,N`-Bis(1`-Hydroxy-2`-Acetonaphthone)Propylenediamine: Synthesis, Extractive Properties, And Use As An Ionophore In A Cu(Ii)-Selective Potentiometric Sensor, Daryoush Emadi, Mohammad Reza Yaftian, Saeed Rayati

Turkish Journal of Chemistry

The binding ability of N,N'-bis(1'-hydroxy-2'-acetonaphthone)propylenediimine (H_2L) towards metal ions was investigated by performing liquid-liquid extraction experiments to extract Cu^{2+}, Ni^{2+}, Co^{2+}, and Zn^{2+} ions from nitrate solutions. Extraction takes place by a cation exchange mechanism and the ligand shows a pronounced selectivity towards Cu^{2+} ions. Conventional log-log analysis of the extraction data reveals that the Cu^{2+} ions are extracted by a 1:1 (metal to ligand) complex formation. The effect of parameters influencing the extraction process, such as type of diluent and concentration of electrolyte in the aqueous phase, has been studied. The selectivity of the ligand was evaluated by competitive …

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Preparation, Spectroscopy, Antimicrobial Assay, And X-Ray Structure Of Dimethyl Bis-(4-Methylpiperidine Dithiocarbamato-S,S`)-Tin(Iv), Zia-Ur Rehman, Saira Shahzadi, Saqib Ali, Guo-Xin Jin Jan 2007

Preparation, Spectroscopy, Antimicrobial Assay, And X-Ray Structure Of Dimethyl Bis-(4-Methylpiperidine Dithiocarbamato-S,S`)-Tin(Iv), Zia-Ur Rehman, Saira Shahzadi, Saqib Ali, Guo-Xin Jin

Turkish Journal of Chemistry

Dimethyl bis(4-methylpiperidine dithiocarbamato-S,S')-tin(IV) was synthesized and characterized by elemental analysis, IR and mass spectrometry, multinuclear NMR (^1H- and ^{13}C-NMR), and X-ray single crystal analysis. IR data showed that the ligand acts as a bidentate in the solid state. X-ray data showed the unsymmetrical nature of the ligand towards coordination to tin. It crystallized in the monoclinic P2_1/n space group. Its geometry is distorted octahedral. Antimicrobial activity data shows that the complex exhibits significantly more activity than the free ligand.

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Pvc-Membrane Electrodes Based On 18-Crown-6 And Dibenzo-18-Crown-6 Ethers For Determination Of Silver, Mohsen Mousa Zareh, Magda A. Akl, Ahmd Khlil Gohneim, Mohmed Hussin Abd El-Aziz Jan 2007

Pvc-Membrane Electrodes Based On 18-Crown-6 And Dibenzo-18-Crown-6 Ethers For Determination Of Silver, Mohsen Mousa Zareh, Magda A. Akl, Ahmd Khlil Gohneim, Mohmed Hussin Abd El-Aziz

Turkish Journal of Chemistry

PVC-membrane electrodes for Ag^+ based on either 18-crown-6 (I) or di-benzo-18-crown-6 ether (II) were applied for the first time. The effect of solvent mediator on the electrode performance was discussed. Nernstian slope values were 59 and 58.9 mV/decade for both I and II electrode types, respectively. The linear concentration range was 10^{-5}-10^{-1}M. The detection limit was 7.9 \times 10^{-6} M. The working pH ranges were 5-9 or 4-9, depending on the concentration of Ag^+ ion. The electrodes showed good selectivity towards most of the common alkali, alkaline earths, and transition metal cations. The electrodes were applied successfully for the determination …

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A Novel Degradable Adsorbent Of The Hyperbranched Aliphatic Polyester Grafted Cellulose For Heavy Metal Ions, Peng Liu Jan 2007

A Novel Degradable Adsorbent Of The Hyperbranched Aliphatic Polyester Grafted Cellulose For Heavy Metal Ions, Peng Liu

Turkish Journal of Chemistry

A novel degradable adsorbent for the removal of heavy metal ions from waste water, a hyperbranched aliphatic polyester grafted cellulose (HAPE-Cell), was successfully prepared by the simple one-pot method for the first time. The hyperbranched aliphatic polyester was grafted from the surface hydroxyl groups of natural cotton fibers via the solution polycondensation of the AB_2 monomer, 2, 2-bis(hydroxymethyl)propionic acid (bis-MPA), with the catalysis of p-toluenesulfonic acid (p-TSA). The HAPE-Cell was characterized by elemental analysis, Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The adsorption properties of the HAPE-Cell towards the heavy metal ions (Cu(II), Hg(II), …

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Development Of A New Set Of Additive Parameters For The Estimation Of Geometrical Distortion Of Cycloalkanes From C-13 Nmr Chemical Shifts, Emad A. S. Al-Hyali Jan 2007

Development Of A New Set Of Additive Parameters For The Estimation Of Geometrical Distortion Of Cycloalkanes From C-13 Nmr Chemical Shifts, Emad A. S. Al-Hyali

Turkish Journal of Chemistry

A previous model for the calculation of C-13 chemical shifts is modified by replacement of 3 parameters representing the p-character of carbon atom in cyclic systems with a single parameter aiming for the development of a new set of parameters with a wide range of application for the calculation of C-13 NMR chemical shifts. The considered systems are cyclohexanes, trans decalins, and a number of hypothetical polycyclic 6-member ring hydrocarbons. The developed parameters include a combination of quantum mechanical and statistical methods. They are based on 2 factors: through bond (electronic) effect represented by the partial electronic charge on the …

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The Synthesis Of 2-(Chloromethyl)-6-Hydroxy-2h-Pyran-3 (6h)-One Via Achmatowicz Rearrangement, Zuhal Gerçek Jan 2007

The Synthesis Of 2-(Chloromethyl)-6-Hydroxy-2h-Pyran-3 (6h)-One Via Achmatowicz Rearrangement, Zuhal Gerçek

Turkish Journal of Chemistry

Achmatowicz rearrangement was carried out with 2-chloro-1-(furan-2-yl) ethanol, which was synthesized starting from 1-(furan-2-yl) ethanone. It was shown that the oxidation of 2-chloro-1-(furan-2-yl) ethanol with m-CPBA produced 2-(chloromethyl)-6-hydroxy-2H-pyran-3 (6H)-one in good yield (70%).

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Cover And Contents Jan 2007

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

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Preconcentration Of Trace Elements On Amberlite Xad-4 Resin Functionalised With 1,2-Bis (O-Aminophenylthio) Ethane And Their Determination By Faas In Environmental Samples, Ömer Dalman, Volkan Numan Bulut, İsmai̇l Deği̇rmenci̇oğlu, Mehmet Tüfekçi̇ Jan 2007

Preconcentration Of Trace Elements On Amberlite Xad-4 Resin Functionalised With 1,2-Bis (O-Aminophenylthio) Ethane And Their Determination By Faas In Environmental Samples, Ömer Dalman, Volkan Numan Bulut, İsmai̇l Deği̇rmenci̇oğlu, Mehmet Tüfekçi̇

Turkish Journal of Chemistry

The use of chemically modified XAD-4-1,2-bis (o-aminophenylthio) ethane chelating resin for preconcentrating Cr^{6+}, Mn^{2+}, Fe^{3+}, Co^{2+}, Cu^{2+}, Cd^{2+}, Zn^{2+}, Pb^{2+}, and Ni^{2+} was studied using flame atomic absorption spectrometry (FAAS) for metal monitoring in environmental samples. Cd^{2+}, Zn^{2+}, Pb^{2+}, and Ni^{2+} ions were quantitatively recovered at the rate of 96.0%, 101.0%, 101.0%, and 95.0%, respectively (RSD < 5%), from the studied solutions. The procedure is based on the retention of analytes on a short column of 1,2-bis (o-aminophenylthio) ethane-XAD-4 chelating resin from a buffered sample solution and subsequent elution with 1 M HNO_3. Various parameters, such as pH, eluent type, and concentration, flow rate of sample solution and matrix interference effect on the retention of the metal ions have been studied. The optimum pH for the sorption of the above-mentioned metal ions was about 6. The adsorption and batch capacity of adsorbent and loading half time (t_{1/2}) for Ni^{2+}, Zn^{2+}, Cd^{2+}, and Pb^{2+} were established. The limit of detection was 3.0 \mu g L^{-1} for Pb^{2+} and Ni^{2+}, 0.6 \mu g L^{-1} for Cd^{2+}, and 0.3 \mu g L^{-1} for Zn^{2+}. The validation of the procedure was carried out by analysis of certified reference materials and standard addition. The proposed enrichment method was applied to environmental samples from Trabzon.

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Catalytic Combustion Of Ethyl Acetate, Tuğba Gürmen Özçeli̇k, Süheyda Atalay, Erden Alpay Jan 2007

Catalytic Combustion Of Ethyl Acetate, Tuğba Gürmen Özçeli̇k, Süheyda Atalay, Erden Alpay

Turkish Journal of Chemistry

The catalytic combustion of ethyl acetate over prepared metal oxide catalysts was investigated. CeO, Co_2O_3, Mn_2O_3, Cr_2O_3, and CeO-Co_2O_3 catalysts were prepared on monolith supports and they were tested. Before conducting the catalyst experiments, we searched for the homogeneous gas phase combustion reaction of ethyl acetate. According to the homogeneous phase experimental results, 45% of ethyl acetate was converted at the maximum reactor temperature tested (350 °C). All the prepared catalysts were tested in order to find the best catalyst for the complete combustion of ethyl acetate. According to the results, all these catalysts produced higher conversion rates than that …

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Synthesis Of Piperazine Based Polyimide In The Presence Of Ionic Liquids, Bülent Alici, Süleyman Köytepe, Turgay Seçki̇n Jan 2007

Synthesis Of Piperazine Based Polyimide In The Presence Of Ionic Liquids, Bülent Alici, Süleyman Köytepe, Turgay Seçki̇n

Turkish Journal of Chemistry

Ionic liquids derived from imidazolium, pyridinium, and alkylammonium salts were investigated not only as catalysts but also as solvents in polymerization of 1,4-bis(3-aminopropyl) piperazine. Results were compared with the conventional polymerizations in N-methylpyrrolidone (NMP). The catalyst has not only a detectable influence on polymer solubility, but also the degrees of polymerization are notably higher. They are even greater than the values obtained by conventional 2-stage polymerization in organic liquids. Ionic liquids based on imidazolium salts seem preferable over pyridinium and alkylammonium salts due to the higher degree of polydispersity of the polyimides obtained. The glass transition temperatures and thermal stabilities …

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Examination Of Some Commercial Sorptive Organobentonites, Müşerref Önal Jan 2007

Examination Of Some Commercial Sorptive Organobentonites, Müşerref Önal

Turkish Journal of Chemistry

For controlling organophilic partition nanophase (OPN) formation in some commercial sorptive organobentonites (OBs), 4 sample were selected randomly and examined by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, differential thermal analysis (DTA), thermal gravimetric analysis (TGA), element analysis (EA), and nitrogen adsorption/desorption (N_2-AD) techniques. Since the d(001) values of the OB samples are between 1.94 and 3.36 nm, the pseudotrilayer or paraffin-type alkylammonium configuration located between the 2:1 layers of smectites is dominant. The bending and stretching type FTIR bands of the smectite surface and alkylammonium cations (AACs) are evidence of the formation of the OPN in the OBs. …

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Cover And Contents Jan 2007

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

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Synthesis And Isolation Of 1-Cyclohex-1,2-Dien-1-Ylbenzene From 1-(2-Iodocyclohex-1-En-1-Yl)Benzene And 1-(2-Iodocyclohex-2-En-1-Yl)Benzene, Mustafa Ceylan, Yakup Budak, M. Burcu Gürdere, İrfan Özdemi̇r, Esra Findik Jan 2007

Synthesis And Isolation Of 1-Cyclohex-1,2-Dien-1-Ylbenzene From 1-(2-Iodocyclohex-1-En-1-Yl)Benzene And 1-(2-Iodocyclohex-2-En-1-Yl)Benzene, Mustafa Ceylan, Yakup Budak, M. Burcu Gürdere, İrfan Özdemi̇r, Esra Findik

Turkish Journal of Chemistry

The key compounds, 1-(2-iodocyclohex-1-en-1-yl) benzene (12) and 1-(2-iodocyclohex-2-en-1-yl) benzene (13), for the generation of 1-cyclohex-1,2-dien-1-ylbezene (20) were synthesized starting with cyclohexanone. Separate reactions of 12 and 13 with KOtBu in benzene in a sealed tube at 180 °C gave 6 products: 1-cyclohex-1-en-1-ylbenzene (8), 2-phenylcyclohexanone (10), 1,8-diphenyl-2,3,4,4a,4b,5,6,7-octahydrobiphenylene (21), 8a-phenyl-1,2,3,4,6,7,8,8a-octahyd-rotriphenylene (22), 1,2-diphenylcyclohexene (23), and 1-(2-tert-butoxycyclohex-1-enyl) benzene (24). In addition, reactions of 12 and 13 under the same conditions in the presence of diphenylisobenzofuran and furan as trapping reagents afforded the [4 + 2] cyclo-adducts 30, 31, and 32 in good yields, respectively.

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Synthesis Of The Amide Derivatives Of 3-[1-(3-Pyridazinyl)-5-Phenyl-1h-Pyrazole-3-Yl]Propanoic Acids As Potential Analgesic Compounds, Erden Banoğlu, Murat Şüküroğlu, Burcu Çalişkan Ergün, Sultan Nacak Baytaş, Eda Aypar, Mustafa Ark Jan 2007

Synthesis Of The Amide Derivatives Of 3-[1-(3-Pyridazinyl)-5-Phenyl-1h-Pyrazole-3-Yl]Propanoic Acids As Potential Analgesic Compounds, Erden Banoğlu, Murat Şüküroğlu, Burcu Çalişkan Ergün, Sultan Nacak Baytaş, Eda Aypar, Mustafa Ark

Turkish Journal of Chemistry

A series of structurally diverse amide derivatives of 3-[1-(3-pyridazinyl)-5-phenyl-1H-pyrazole-3-yl]propanoic acids were prepared and tested for their in vivo analgesic activity using an acetic acid induced writhing test. All the test compounds displayed approximately equipotent analgesic activity to aspirin. The results showed that the analgesic activity of 5a, 5f, 5n, and 5o is significantly higher than that of 5d.

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Dinuclear Molybdenum Tetracarbonyl Complexes Of Tetradentate Nitrogen Ligands And Intermolecular Hydrogen Bonding In The Crystal Structure Of N,N´-Bis-[1-(Pyridin-2-Yl)Ethylidene]-Ethane-1,2-Diamine, Ayfer Menteş, Seda Sezek, M. Emre Hanhan, Orhan Büyükgüngör Jan 2007

Dinuclear Molybdenum Tetracarbonyl Complexes Of Tetradentate Nitrogen Ligands And Intermolecular Hydrogen Bonding In The Crystal Structure Of N,N´-Bis-[1-(Pyridin-2-Yl)Ethylidene]-Ethane-1,2-Diamine, Ayfer Menteş, Seda Sezek, M. Emre Hanhan, Orhan Büyükgüngör

Turkish Journal of Chemistry

Multidentate N-ligands (Schiff bases) were prepared by the condensation of 2-acetylpyridine or 2-benzoylpyridine, and 1,2-diaminoethane or 1,6-diaminohexane (2:1 ratio) in ethanol. These ligands were reacted with Mo(CO)_6 to obtain dinuclear metal tetracarbonyl compounds. Both terminal amine groups were seen to form imines from the reaction of mono-ketones with diamines in 2:1 or 1:1 ratios. The structures of these ligands and metal complexes were characterized by elemental analysis, and FT-IR, ^1H-NMR, ^{13}C-NMR, and LC-MS spectral techniques. N,N'-bis[1-(pyridin-2-yl)ethylidene]ethane-1, 2-diamine, which was obtained by the reaction of 2-acetylpyridine and 1,2-diaminoethane, was also characterized by single crystal X-ray structure analysis. The crystal packing is …

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Synthesis And Characterization Of Nife_2o_4 Nano-Octahedrons By Edta-Assisted Hydrothermal Method, Nermi̇n Kasapoğlu, Abdulhadi̇ Baykal, Muhammet S. Toprak, Yüksel Köseoğlu, Harun Bayrakdar Jan 2007

Synthesis And Characterization Of Nife_2o_4 Nano-Octahedrons By Edta-Assisted Hydrothermal Method, Nermi̇n Kasapoğlu, Abdulhadi̇ Baykal, Muhammet S. Toprak, Yüksel Köseoğlu, Harun Bayrakdar

Turkish Journal of Chemistry

Octahedral-like NiFe_2O_4 ferrite nanocrystals were synthesized using EDTA-assisted hydrothermal method under mild conditions. XRD and FTIR analysis were used for composition and structure investigation. XRD analysis revealed a pure ferrite phase with high crystallinity. Morphological investigation by SEM showed octahedral nanocrystals with an average particle size of \sim 40 nm. Crystallite size calculated from XRD peak broadening resulted in an average crystallite size of 39 nm, matching well with the SEM observations. TEM analysis and corresponding electron diffraction confirmed the octahedral morphology and single crystallinity of octahedral nanoparticles. Magnetic measurements showed that NiFe_2O_4 octahedrons have smaller coercivity than bulk ferrite …

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Direct Hydrothermal Synthesis Of Palladium-Incorporated Silicate-Structured Mesoporous Catalysts, Canan Şener, Ti̇mur Doğu, Gülşen Doğu Jan 2007

Direct Hydrothermal Synthesis Of Palladium-Incorporated Silicate-Structured Mesoporous Catalysts, Canan Şener, Ti̇mur Doğu, Gülşen Doğu

Turkish Journal of Chemistry

Pd-Si-structured novel mesoporous nanocomposite catalytic materials, having quite high Pd/Si ratios, were synthesized by an acidic direct hydrothermal synthesis route. The nanocomposite catalytic materials were then characterized by XRD, XPS, EDS, nitrogen adsorption, and SEM techniques. Unlike MCM-41, the XRD patterns indicated a rather wide d_{(100)} band at a 2\theta value of about 1.9. The materials, with very high Pd/Si wt ratios between 1.43 and 2.66, were synthesized and had BJH surface area values between 600 and 200 m^2/g. The pore size distributions of these materials were also quite narrow, indicating pores between 2 and 7 nm.

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Characterization And Co Oxidation Activity Studies Of Co-Based Catalysts, Fi̇li̇z Balikçi, Çi̇ğdem Güldür Jan 2007

Characterization And Co Oxidation Activity Studies Of Co-Based Catalysts, Fi̇li̇z Balikçi, Çi̇ğdem Güldür

Turkish Journal of Chemistry

Cobalt oxide based catalysts were developed for carbon monoxide oxidation at low temperature. The catalysts were prepared by co-precipitation and calcined at 200 °C. Several techniques were used to characterize the catalysts, such as X-ray diffractometer system, N_2 physisorption measurements, scanning electron microscope (SEM), and X-ray photoelectron spectroscopy. Carbon monoxide oxidation studies were carried out to investigate the relation between the characteristic properties of the catalysts and the catalytic activity. Catalytic activity measurements were studied from room temperature to 200 °C, using a feed composition of 1% CO, 21% O_2, and remaining He. X-ray studies showed that the catalysts have …

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Kinetics Of Synthesis Of Isobutyl Propionate Over Amberlyst-15, Ali̇me İzci̇, Hali̇t Levent Hoşgün Jan 2007

Kinetics Of Synthesis Of Isobutyl Propionate Over Amberlyst-15, Ali̇me İzci̇, Hali̇t Levent Hoşgün

Turkish Journal of Chemistry

The esterification of propionic acid with isobutanol in the presence of Amberlyst-15 as a catalyst was studied. Isobutyl propionate synthesized in this reaction has the fragrance of rum and is used in the food industry. The experiments were carried out in a stirred batch reactor at temperatures from 318 K to 348 K. As a solvent, 1,4 dioxan was used. The effects of the amount of catalyst used, the reaction time, the stirring speed, and the reaction temperature on the synthesis of isobutyl propionate were investigated. It was observed that solid-liquid external mass transfer resistance resulting from various stirring speeds …

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Low Temperature Co Oxidation Kinetics Over Activated Carbon Supported Pt-Sno_X Catalysts, Fatma Soyal Baltacioğlu, Berri̇n Gülyüz, Ahmet Erhan Aksoylu, Zeynep İlsen Önsan Jan 2007

Low Temperature Co Oxidation Kinetics Over Activated Carbon Supported Pt-Sno_X Catalysts, Fatma Soyal Baltacioğlu, Berri̇n Gülyüz, Ahmet Erhan Aksoylu, Zeynep İlsen Önsan

Turkish Journal of Chemistry

The kinetics of low temperature CO oxidation were studied over sequentially impregnated 1wt%Pt-0.25wt%SnO_x supported on HNO_3-oxidized activated carbon (AC3) using a wide range of CO (1-10 mol%) and O_2 (1-4 mol%) concentrations. Intrinsic kinetic data were obtained in the initial rates region at 383 K in the absence and presence of 5-45 mol% H_2 in the feed. A power-function rate expression with positive dependence on CO (0.96) and negative dependence on oxygen (--0.31) was obtained for the low temperature oxidation of CO. The effect of H_2 on CO oxidation rates was also investigated under similar conditions.

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A Mechanistic Approach To Elucidate Ethanol Electro-Oxidation, Ni̇yazi̇ Alper Tapan Jan 2007

A Mechanistic Approach To Elucidate Ethanol Electro-Oxidation, Ni̇yazi̇ Alper Tapan

Turkish Journal of Chemistry

In order to elucidate the mechanism of ethanol oxidation, a simple cylindrical diffusion-surface reaction was developed on a platinum disk electrode. An ethanol electro-oxidation mechanism was proposed, in which electrochemical reactions proceed without adsorption of any electro-oxidation products (C2 type) on the surface. After the simulation of the proposed mechanism, it was seen that the model can explain ethanol electro-oxidation behavior without any surface CO formation. The simulation of the mechanism indicated that the formation of acetaldehyde through the oxidation of bulk ethanol is the rate determining step between 0.6 and 0.75 V vs. RHE. After 0.75 V vs. RHE, …

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Port Competitiveness In North East Asia : An Integrated Fuzzy Approach To Expert Evaluations, Gi-Tae Yeo Jan 2007

Port Competitiveness In North East Asia : An Integrated Fuzzy Approach To Expert Evaluations, Gi-Tae Yeo

Plymouth Business School Theses

Despite the fact that the Northeast Asia (NEA) region, which had four of the top five and 20 of the top 30 container ports in the world in 2003, can be regarded as holding a central position in liner shipping and the handling of container cargo volumes, very little research has been done into the evaluation of its port competitiveness (EPC). For this reason, the EPC in NEA can be regarded as a problematic and urgent issue to be solved, and worthy of academic attention. From this aspect, this research set out to attempt to address the above issue by …

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Impact Of Culture On Stock Market Development And Corporate Governance, Walaa Wahid Eldin Elkelish Jan 2007

Impact Of Culture On Stock Market Development And Corporate Governance, Walaa Wahid Eldin Elkelish

Plymouth Business School Theses

This study takes a step forward to explore the dynamic relationship between cultural values and stock market development in the United Kingdom, during the period 1991- 2004. Cultural values are represented by the cultural model of Hofstede (1980) which consists of five dimensions, which are: power distance, uncertainty avoidance, individualism, masculinity and time horizon. Stock market developmenti s representedb y four indicators, which are: stock market activity, size, liquidity and concentration. Empirical results, using structural equation modelling (SEM), show that some cultural values have significant relationships with stock market development indicators. Power distance has a significant negative relationship with stock …

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