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2003

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Articles 301 - 330 of 463

Full-Text Articles in Chemistry

^1h Nmr Studies Of Some Imidazole Ligands Coordinated To Co(Iii), Kosrow Zamani, Akbar Mobinikhaledi, Naser Foroughifar, Khalil Faghihi, Vahid Mahdavi Jan 2003

^1h Nmr Studies Of Some Imidazole Ligands Coordinated To Co(Iii), Kosrow Zamani, Akbar Mobinikhaledi, Naser Foroughifar, Khalil Faghihi, Vahid Mahdavi

Turkish Journal of Chemistry

Chemical shifts for proton signals of an imidazole ring coordinated to Co(III) move downfield as the total complex charge increases. However, the C_{(2) - H} chemical shift of the imidazole ring in cis-[Co(en)_{2}(N-mIm) OPO_{3}H]°, which has no charge compared to those of cis-[Co(en)_{2}(N-mIm) OPO_{3}H]^{+} and cis}-[Co(en)_{2}(N-mIm) OPO_{3}H_{2}]^{2 +} , moves downfield. These unexpected phenomena could be attributed to an intramolecular interaction between the phosphate anion group and C_{(2) - H} of the imidazole ligand.

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Thermal Decomposition Kinetics Of Anilino-P-Chlorophenylglyoxime Complexes Of Cobalt (Ii), Nickel (Ii) And Copper (Ii), Hakan Arslan, Nevzat Külcü, Ali̇ İhsan Pekacar Jan 2003

Thermal Decomposition Kinetics Of Anilino-P-Chlorophenylglyoxime Complexes Of Cobalt (Ii), Nickel (Ii) And Copper (Ii), Hakan Arslan, Nevzat Külcü, Ali̇ İhsan Pekacar

Turkish Journal of Chemistry

The Co(II), Ni(II) and Cu(II) complexes of anilino-p-chlorophenylglyoxime were synthesised. The thermal behaviour of all complexes was studied by DTA and TG. It was found that pyrolytic decomposition occurs with melting in metal complexes and that metal oxides remain as final products of the metal complexes. A GC-MS combined system was used to identify the products during pyrolytic decomposition. The pyrolytic end products were identified by x-ray powder diffraction. The orders, n, the activation energies, E^*, the pre-exponential factors, A, and the entropies, \Delta S^*, of thermal decomposition reactions were derived from thermogravimetric and differential thermogravimetric curves. The kinetic analysis …

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Conductimetric And Potentiometric Investigation Of Effects Of Solvents And Titrant On Formation Of Homoconjugates, Esi̇n Canel, Mustafa Taşteki̇n, Orhan Atakol, Esma Kiliç Jan 2003

Conductimetric And Potentiometric Investigation Of Effects Of Solvents And Titrant On Formation Of Homoconjugates, Esi̇n Canel, Mustafa Taşteki̇n, Orhan Atakol, Esma Kiliç

Turkish Journal of Chemistry

Trichloro-, tribromo- and trifluoro- acetic acids were both conductimetrically and potentiometrically titrated in acetonitrile and 2-propanol media. The titrations were carried out at 25°C under nitrogen atmosphere and titrants used were the solutions of triethyl, di-n-butyl and n-butyl amines prepared in the same solvents. Whether these acids gave a homoconjugation reaction during titration was investigated by the use of conductimetric and potentiometric titration curves. In acetonitrile media trichloro- and tribromo-acetic acids decomposed to give chloroform and carbon dioxide, and bromoform and carbon dioxide respectively. It was observed that the acid concentration and the type of titrant used had no effect …

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Chromatographic Determination Of Phenolic Acids In The Snowdrop By Hplc, Mustafa Tüzen, Mustafa Özdemi̇r Jan 2003

Chromatographic Determination Of Phenolic Acids In The Snowdrop By Hplc, Mustafa Tüzen, Mustafa Özdemi̇r

Turkish Journal of Chemistry

Free and esterified phenolic acids of Galanthus elwesii (snowdrop) were extracted with petroleum ether and determined by HPLC. Cinnamic, ferulic, vanillic, p-coumaric, p-hydroxy benzoic, and caffeic acids were detected by a linear gradient elution with acetic acid/water (2:98 v/v) and acetic acid/acetonitrile/water (2:30:68 v/v) as the mobile phases in 30 min with a flow rate of 1.5 mL/min. Among the acids from snowdrop extracts, p-hydroxy benzoic was the major constituent followed by vanillic and ferulic acids.

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Purification And Partial Characterization Of Catalase From Chicken Erythrocytes And The Effect Of Various Inhibitors On Enzyme Activity, Tüli̇n Aydemi̇r, Kevser Kuru Jan 2003

Purification And Partial Characterization Of Catalase From Chicken Erythrocytes And The Effect Of Various Inhibitors On Enzyme Activity, Tüli̇n Aydemi̇r, Kevser Kuru

Turkish Journal of Chemistry

Catalase plays a major role in the protection of tissues from the toxic effects of H_{2}O_{2} and partially reduced oxygen species. A nearly 136-fold enzyme purification was obtained from chicken erythrocyte by acetone precipitation, ethanol-chloroform treatment, CM-cellulose and Sephadex G-200 chromatography. The specific activity of purified enzyme was 42,556 U/mg. The molecular weight of the native chicken erythrocyte catalase was estimated at 240 kDa by gel filtration. SDS-gel electrophoresis results indicated that chicken erythrocyte catalase consists of four apparently identical subunits, with a molecular weight of around 57.5 kDa. The optical spectrum of the purified enzyme shows a Soret band …

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Kinetics Of Aqueous Pyrite Oxidation By Potassium Dichromate - An Experimental Study, Paul Chirita Jan 2003

Kinetics Of Aqueous Pyrite Oxidation By Potassium Dichromate - An Experimental Study, Paul Chirita

Turkish Journal of Chemistry

The kinetics of pyrite oxidation in perchloric acid solutions were investigated at temperatures ranging from 30°C to 40°C, potassium dichromate concentration from 0.001 to 0.05 mol L^{ - 1}, particle size fractions from 50 to 150 \mu m and pH values down to 2.83. The rate of the oxidation reaction is described by the following expression: r = bkS^{0.51}[K_{2}Cr_{2}O_{7}]^{0.64}[H^{+} ]^{0.22} where S is the surface area of reacting solid, r represents the amount of Fe release in solution per unit surface area per unit time, b is a stoichiometric factor, k is the rate constant, and [K_{2}Cr_{2}O_{7}] and [H^{+} ] …

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Electrochemical Behaviour Of Thymolphthalein, Mustafa Uçar, Necati̇ Menek Jan 2003

Electrochemical Behaviour Of Thymolphthalein, Mustafa Uçar, Necati̇ Menek

Turkish Journal of Chemistry

The polarographic and voltammetric behaviour of thymolphthalein in ethanol-water (1/5 v/v) was studied using various electrochemical techniques. The reduction of thymolphthalein on a mercury drop electrode was investigated. The adsorption effect on the electrode surface was observed. The rate constants for the electron transfer steps were determined by and without taking adsorption into occount using the Laviron technique and Nicholson technique respectively. The diffusion coefficients were calculated from the cyclic voltammetric data using the method developed by Garrido. Reversibility for the electrode reaction was investigated and a mechanism for the electrode reaction was proposed.

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Flow Injection Amperometric Determination Of Ascorbic Acid Using A Photoelectrochemical Reaction After Immobilization Of Methylene Blue On Muscovite, Yusuf Di̇lgi̇n, Zekerya Dursun, Gürel Ni̇şli̇ Jan 2003

Flow Injection Amperometric Determination Of Ascorbic Acid Using A Photoelectrochemical Reaction After Immobilization Of Methylene Blue On Muscovite, Yusuf Di̇lgi̇n, Zekerya Dursun, Gürel Ni̇şli̇

Turkish Journal of Chemistry

The photoelectrochemical determination of ascorbic acid (AA) was studied based on the photochemical reduction of methylene blue (MB) in 0.1 M phosphate buffer (pH 7.0). MB was used as a redox mediator for the modification of a carbon paste electrode (CPE) due to its facile reducible-oxidizible behaviour. Muscovite, which has a layered structure, was found to be a good and stable supporting material for the immobilization of MB by an ion exchange reaction. The dye is strongly retained and not easily leached from the matrix. MB was reduced to nearly quasi-reversible at the modified carbon paste electrode (MCPE). The oxidation …

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Inhibition Studies Of A Few Organic Compounds And Their Condensation Products On The Corrosion Of Zinc In Hydrochloric Acid Medium, Shanthamma K. Rajappa, Thimmappa V. Venkatesha Jan 2003

Inhibition Studies Of A Few Organic Compounds And Their Condensation Products On The Corrosion Of Zinc In Hydrochloric Acid Medium, Shanthamma K. Rajappa, Thimmappa V. Venkatesha

Turkish Journal of Chemistry

The corrosive behavior of zinc in HCl solution containing various concentrations of glutaraldehyde GTD, glycine GLN, methionine MTN, and their condensation products formed between GTD + GLN (CP1) and GTD + MTN (CP2) was investigated. The corrosion-inhibitive action of these compounds on zinc metal was studied using chemical and electrochemical methods. The results showed that the compound CP2 is the best inhibitor and that its inhibition efficiency reaches 92.56% at 10^{-2} M in 0.05 M acid concentration. As an inhibitor, CP2 was found to have a predominant cathodic effect and its adsorption was confirmed with the Temkin isotherm. The effect …

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Evaluation Of Thermal Decomposition Kinetics Of Borax Pentahydrate Using Genetic Algorithm Method By Isothermal Analysis, Ömer Şahi̇n, A. Nusret Bulutcu Jan 2003

Evaluation Of Thermal Decomposition Kinetics Of Borax Pentahydrate Using Genetic Algorithm Method By Isothermal Analysis, Ömer Şahi̇n, A. Nusret Bulutcu

Turkish Journal of Chemistry

The thermal calcination of borax pentahydrate was investigated for both dehydration and decomposition steps at temperatures between 392 and 573 K in a controlled fluidized bed drier. The best kinetic parameters (reaction rate constants, reaction order and equilibrium values) of both steps were determined by the genetic algorithm (GA) method for each calcination temperature in respect of relative standard deviation. The values of the kinetic parameters showed that the dehydration step of borax pentahydrate was controlled by a homogeneous reaction of the order of about 2/3 whereas the decomposition step was controlled by a reaction order of about 1. These …

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Organotin(Iv) Complexes Of Aniline Derivatives Part-Ii - Synthesis And Spectroscopic Characterization Of Organotin(Iv) Derivatives Of 2-[(4-Bromoanilino)Carboxyl]Benzoic Acid, Khadija Shahid, Saqib Ali, Saira Shahzadi, Zareen Akhtar Jan 2003

Organotin(Iv) Complexes Of Aniline Derivatives Part-Ii - Synthesis And Spectroscopic Characterization Of Organotin(Iv) Derivatives Of 2-[(4-Bromoanilino)Carboxyl]Benzoic Acid, Khadija Shahid, Saqib Ali, Saira Shahzadi, Zareen Akhtar

Turkish Journal of Chemistry

A series of organotin(IV) complexes with the general formula R_{2}SnL_{2} and R_{3}SnL, where R = CH_{3}, C_{2}H_{5}, n-C_{4}H_{9}, C_{6}H_{5}, C_{6}H_{5}CH_{2} and L = 2-[(4-bromoanilino)carboxyl]benzoate, were synthesized and characterized by infrared, mass and multinuclear NMR (^{1}H, ^{13}C, ^{119}Sn) spectroscopies. The coordination around tin in solid as well as in solution has been proposed on the basis of spectroscopic results.

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Characterization Of Polyphenol Oxidase From Jerusalem Artichoke (Helianthus Tuberosus), Emi̇ne Zi̇yan, Şule Pekyardimci Jan 2003

Characterization Of Polyphenol Oxidase From Jerusalem Artichoke (Helianthus Tuberosus), Emi̇ne Zi̇yan, Şule Pekyardimci

Turkish Journal of Chemistry

Polyphenol oxidases (PPO) in Jerusalem arthichoke (Helianthus tuberosus) skin and flesh were extracted and purified through (NH_{4})_{2}SO_{4} precipitation, dialysis and gel filtration chromatography. The samples obtained from ammonium sulfate precipitation and dialysis were used for the characterization of crude skin and flesh PPO. Optimum pH values were 7.5 for skin PPO and 8.0 for flesh PPO with 50 mM catechol. The optimum temperatures for skin and flesh PPO were 25 °C and 30 °C respectively with catechol. Six inhibitors were tested in the study and the most effective inhibitors were found to be sodium azide and thiourea for both flesh …

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Flow Injection Speciation Analysis Of Manganese In Real Samples By Diphenylcarbazide-Spectrophotometric Determination, Kazem Kargosha, Meissam Noroozifar Jan 2003

Flow Injection Speciation Analysis Of Manganese In Real Samples By Diphenylcarbazide-Spectrophotometric Determination, Kazem Kargosha, Meissam Noroozifar

Turkish Journal of Chemistry

The flow injection speciation of manganese in aqueous solution using a spectrophotometry method of detection is presented. Manganese (VII) can be determined spectrophotometrically at 308 nm after the reaction with Sym-diphenycarbazide in buffered at pH = 3.05 with phosphate. Under the optimized conditions, total manganese concentration can also be determined after oxidation of Mn^{2+} to MnO_{4}^{-} and then Mn^{2+} concentration can be calculated from the difference. The linear range of determination is 0.047-4.50 mg/l with a 3\sigma detection limit of 31 \mu g/l. The proposed method is applied to the determination of MnO_{4}^{-} and Mn^{2+} in effluent streams and foods …

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The Kinetic Study Of The Chemical Oscillating System Of 1,3-Propanediol/Acetone As The Organic Substrate, Shi-Gang Shen, Caiqin Yang, Han-Wen Sun, Jin-Huan Shan, Ying Liu Jan 2003

The Kinetic Study Of The Chemical Oscillating System Of 1,3-Propanediol/Acetone As The Organic Substrate, Shi-Gang Shen, Caiqin Yang, Han-Wen Sun, Jin-Huan Shan, Ying Liu

Turkish Journal of Chemistry

This work was primarily an experimental investigation of the bromate oscillator using 1,3-propanediol and acetone as the mixed organic substrates. The empirical equation of the induction period and oscillating period with the concentrations of the reactants and temperature were obtained. The oscillating characteristic and possible oscillation mechanism were studied.

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Kinetics And Mechanism Of Oxidation Of Some Hydroxy Butyric Acid Salts By Ditelluratocuprate(Iii) In Alkaline Medium, Jin-Huan Shan, Li-Ping Wang, Shi-Gang Shen, Han-Wen Sun Jan 2003

Kinetics And Mechanism Of Oxidation Of Some Hydroxy Butyric Acid Salts By Ditelluratocuprate(Iii) In Alkaline Medium, Jin-Huan Shan, Li-Ping Wang, Shi-Gang Shen, Han-Wen Sun

Turkish Journal of Chemistry

The kinetics of oxidation of 2-hydroxy butyric acid salt (2-HBAS) and 3-hydroxy butyric acid salt (3-HBAS) by ditelluratocuprate(III) (DTC) were studied spectrophotometrically between 298.2 K and 313.2 K in alkaline medium. The reaction rate showed first order dependence in DTC and a fractional order in HBAS. It was found that the pseudo-first order rate constant k_{obs} increased with an increase in the concentration of OH^- and a decrease in the concentration of TeO_{4}^{2-}. The reaction rate changed with the position of the hydroxyl group. There was a negative salt effect. A plausible mechanism involving a pre-equilibrium of adduct formation between …

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Iridoid And Phenylpropanoid Glycosides From Phlomis Samia, P. Monocephala And P. Carica, Funda Nuray Yalçin, Tayfun Ersöz, Pinar Akbay, İhsan Çaliş, Ali̇ Arslan Dönmez, Otto Sticher Jan 2003

Iridoid And Phenylpropanoid Glycosides From Phlomis Samia, P. Monocephala And P. Carica, Funda Nuray Yalçin, Tayfun Ersöz, Pinar Akbay, İhsan Çaliş, Ali̇ Arslan Dönmez, Otto Sticher

Turkish Journal of Chemistry

From the aerial parts of Phlomis samia an iridoid glucoside, shanzhiside methylester (1), and three phenylethanoid glycosides, martynoside (2), 4''-O-acetylmartynoside (3) and samioside (4), were isolated. From the overground parts of P. monocephala two iridoid glucosides, lamiide (5) and ipolamiide (6), as well as three phenylethanoid glycosides, verbascoside (= acteoside) (7), forsythoside B (8), alyssonoside (9), and one lignan glucoside, syringaresinol 4'-O-\beta -D-glucopyranoside (10), were isolated. From the aerial parts of P. carica one phenylethanoid glycoside, verbascoside (= acteoside) (7) and three phenylpropanoid monomeric glucosides, syringin (11), dihydrosyringin (12) and coniferin (13), were isolated. The structures of the isolated compounds …

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Spectrophotometric Determination Of Iron(Ii) With 5-Nitro-6-Amino-1,10-Phenanthroline, Nebahat Demi̇rhan, Fi̇kri̇ye Tuncel Elmali Jan 2003

Spectrophotometric Determination Of Iron(Ii) With 5-Nitro-6-Amino-1,10-Phenanthroline, Nebahat Demi̇rhan, Fi̇kri̇ye Tuncel Elmali

Turkish Journal of Chemistry

A new spectrophotometric method is developed for the determination of Fe(II) with 5-nitro-6-amino-1,10-phenanthroline (NAF). In this work, the effect of factors such as pH, amount of reagent (NAF), reaction time and temperature were investigated. The method is based on the formation of a colored product between Fe(II) and NAF. The reaction proceed quantitatively at 20 °C for 210 min in acidic medium. The absorption maximum was at 520 nm. A linear relationship existed between absorbance and Fe(II) concentration over the range 0.1 \mu g/mL and 0.4 \mu g/mL. The molar ratio of Fe(II) to the reagent was determined as 1:3. …

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Production Of An E. Coli Toxin Protein; Colicin A In E. Coli Using An Inducible System, İsa Gökçe, Jeremy H. Lakey Jan 2003

Production Of An E. Coli Toxin Protein; Colicin A In E. Coli Using An Inducible System, İsa Gökçe, Jeremy H. Lakey

Turkish Journal of Chemistry

Colicins are bacterial toxins that kill Escherichia coli and related cells; their mode of action is of interest in protein import and toxicology. Colicins translocate across the E. coli outer membrane and periplasm by interacting with several receptors. This translocation process involves interaction of the colicin with the outer membrane porin OmpF and subsequently with the integral membrane protein TolA. The N-terminal domain of colicin N is involved in the import process. Our aim was to produce a large quantity of colicin A for functional and structural studies. It is a prerequisite to have a correctly folded and stable protein …

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Application Of A Three-Stage Sequential Extraction Procedure For The Determination Of Extractable Metal Contents In Highway Soils, Şeri̇fe Tokalioğlu, Şenol Kartal, Gökhan Bi̇rol Jan 2003

Application Of A Three-Stage Sequential Extraction Procedure For The Determination Of Extractable Metal Contents In Highway Soils, Şeri̇fe Tokalioğlu, Şenol Kartal, Gökhan Bi̇rol

Turkish Journal of Chemistry

A sequential extraction procedure, a three-step protocol proposed by the Standards, Measurements and Testing programme (SM & T--formerly BCR) of the European Union, was applied to soil samples for the determination of metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn). This procedure provides measurements of extractable metals from media such as acetic acid (0.11 mol L^{-1}), hydroxylammonium chloride (0.1 mol L^{-1}) and hydrogen peroxide (8.8 mol L^{-1}) plus ammonium acetate (1 mol L^{ - 1}), which are exchangeable, reducible and oxidisable metals, respectively. Analyses were carried out using flame atomic absorption spectrometry (FAAS). The results obtained from …

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Simultaneous Determination Of Copper, Zinc And Selenium In Chicken Liver By Differential Pulse Polarography, Güler Ekmekci̇, Güler Somer, Olcay Şendi̇l Jan 2003

Simultaneous Determination Of Copper, Zinc And Selenium In Chicken Liver By Differential Pulse Polarography, Güler Ekmekci̇, Güler Somer, Olcay Şendi̇l

Turkish Journal of Chemistry

A differential pulse polarographic method for the determination of copper, zinc and selenium in chicken liver is described. It was possible to determine these elements in a single sample solution after acid digestion. Dried liver samples weighing about 3 g were digested using HNO_{3} and HClO_{4} acids. Britton-Robinson or acetate buffer has been found suitable as the supporting electrolyte. For the determination of selenium, the hydrogen catalytic peak was used after the addition of molybdenum(VI) to the buffer solution at about pH 3. Then the pH of the same solution was increased to 4 and zinc was determined. For the …

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Aluminum Fractionation In The Water Of Karakaya Dam Lake (Malatya, Turkey), F. Zehra Küçükbay, Mustafa Demi̇r Jan 2003

Aluminum Fractionation In The Water Of Karakaya Dam Lake (Malatya, Turkey), F. Zehra Küçükbay, Mustafa Demi̇r

Turkish Journal of Chemistry

A method was developed for the determination of trace amounts of Al species in water samples using the amberlite type XAD-4 resin. For this purpose, total dissolved Al, organically bonded Al and particulate Al in water samples taken from Karakaya dam lake (Malatya, Turkey) were determined by flame atomic absorption spectroscopy (FAAS) or graphite furnace atomic absorption spectroscopy (GFAAS) after an enrichment procedure. The total dissolved Al in the water samples was determined using 8-hydroxyquinoline as complexing reagent at pH 8 and amberlite type XAD-4 resins for the enrichment. The organically bonded Al species in the water samples were destroyed …

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Atomic Absorption And Spectrophotometeric Determinations Of Salicylhydroxamic Acid In Its Pure And Pharmaceutical Dosage Forms, Alaaeldin Abdelaziz Salem, Mohamed Mohamed Omar Jan 2003

Atomic Absorption And Spectrophotometeric Determinations Of Salicylhydroxamic Acid In Its Pure And Pharmaceutical Dosage Forms, Alaaeldin Abdelaziz Salem, Mohamed Mohamed Omar

Turkish Journal of Chemistry

A new method for the indirect determination of salicylhydroxamic acid (SHAM) using atomic absorption spectrometry (AAS) was proposed. The method is based on precipitating the ion associate complex of SHAM with [Cu (NH_{3})_{4}]^{2+}. The excess, unreacted, Cu^{2+} ions were determined using AAS. Another spectrophotometric method based on measuring the absorbance of the formed [Cu (NH_{3})_{4}]-SHAM complex in dioxane was proposed. The green color of the complex formed was measured at 330 nm. The two methods were successfully used for determining SHAM in its pure and pharmaceutical dosage forms. Using AAS, the drug was determined over a concentration range of 3.06 …

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Purification And Characterization Of Glucose 6-Phosphate Dehydrogenase From Sheep Liver, Vedat Türkoğlu, Si̇nan Aldemi̇r, Mehmet Çi̇ftçi̇ Jan 2003

Purification And Characterization Of Glucose 6-Phosphate Dehydrogenase From Sheep Liver, Vedat Türkoğlu, Si̇nan Aldemi̇r, Mehmet Çi̇ftçi̇

Turkish Journal of Chemistry

Glucose 6-phosphate dehydrogenase (D-glucose 6-phosphate: NADP^{+} oxidoreductase, EC 1.1.1.49; G6PD) was purified from sheep liver by a simple and rapid method. The purification process consisted of two steps: preparation of the homogenate, and 2', 5'-adenosine diphosphate (ADP) Sepharose 4B affinity chromatography. Through the use of these two consecutive steps, the enzyme was purified with a yield of 35.6% and 1,920 fold, having the specific activity of 11.2 enzyme units (EU/mg protein). A K_{M} of 0.176 mM and a V_{\max} of 0.0179 EU/ml were obtained for G6-P, and 0.0194 mM and 0.0223 EU/ml for NADP^{+}. Enzymatic activity was measured spectrophotometrically according …

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Graft Copolymerization Of N-Vinylimidazole On Poly(Ethylene Terephthalate) Fibers In A Swelling Solvent Using Azobisisobutyronitrile As Initiator, Hali̇l İbrahi̇m Ünal, Can İnegöllü, Oya Şanli Jan 2003

Graft Copolymerization Of N-Vinylimidazole On Poly(Ethylene Terephthalate) Fibers In A Swelling Solvent Using Azobisisobutyronitrile As Initiator, Hali̇l İbrahi̇m Ünal, Can İnegöllü, Oya Şanli

Turkish Journal of Chemistry

In this study, poly(ethylene terephthalate) (PET) fibers were grafted in dimethylformamide (DMF) with n-vinylimidazole (n-VI) using azobisisobutyronitrile (AIBN) as an initiator. Variations of percentage grafting with time, temperature, monomer and initiator concentrations as well as monomer and initiator diffusions were investigated. It was observed that the percentage of grafting and grafting efficiency increased as time and temperature rose up to a certain value, and then they levelled off. The percentage of grafting was found to rise with increasing monomer and initiator concentrations, and then decrease. Monomer and initiator diffusions into PET fibers were shown to follow a similar trend and …

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Synthesis Of New Antimicrobial Agents; Amide Derivatives Of Pyranones And Pyridinones, Mutlu Di̇lsi̇z Aytemi̇r, Robert C. Hider, Di̇lek Demi̇r Erol, Meral Özalp, Meli̇ke Eki̇zoğlu Jan 2003

Synthesis Of New Antimicrobial Agents; Amide Derivatives Of Pyranones And Pyridinones, Mutlu Di̇lsi̇z Aytemi̇r, Robert C. Hider, Di̇lek Demi̇r Erol, Meral Özalp, Meli̇ke Eki̇zoğlu

Turkish Journal of Chemistry

In this study, 4(1H)-pyridinones with an amide function in Position 2 of the pyridinone ring showed antimicrobial activity. The synthesis and the biological properties of some novel amide derivatives of pyran-4(1H)-one and 4(1H)-pyridinone have been reported. Amide derivatives of pyran-4(1H)-one and 4(1H)-pyridinone were prepared using two different methods. Antimicrobial activities were determined as MIC values using the microdilution broth method against the bacteria Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa and the fungi Candida albicans, Candida krusei and Candida parapsilosis. Compounds 6 and 9 exhibited the best inhibitor activity against S. aureus.

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Some Polyamidoxime Derivatives And Their Metal Complexes, Fatma Kari̇pci̇n, İbrahi̇m Karataş, Hali̇l İsmet Uçan Jan 2003

Some Polyamidoxime Derivatives And Their Metal Complexes, Fatma Kari̇pci̇n, İbrahi̇m Karataş, Hali̇l İsmet Uçan

Turkish Journal of Chemistry

In this paper the synthesis of six polyamidoximes from their corresponding diamines with 4,4'-methylenebis (phenylglyoxylohydroximoyl chloride) and 4,4'-methylenebis(chlorophenylgly-oxime) is presented. The average molecular weights of these organic polymers were determined. In addition, the complexes of 4,4'-methylenebis (phenylglyoxylohydroximoyl chloride) with Ni(II), Co(II) and Cu(II) salts were prepared. The structures of these compounds were identified by IR or ^{1}H NMR spectral data, elemental analyses, magnetic measurements and thermal analysis.

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Synthesis Of New 4-(5-Chloro-2-Oxo-3h-Benzoxazol-3-Yl)Butanamide Derivatives And Their Analgesic And Anti-Inflammatory Properties, H. Ozan Gülcan, Serdar Ünlü, Erden Banoğlu, M. Fethi̇ Şahi̇n, Esra Küpeli̇, Erdem Yeşi̇lada Jan 2003

Synthesis Of New 4-(5-Chloro-2-Oxo-3h-Benzoxazol-3-Yl)Butanamide Derivatives And Their Analgesic And Anti-Inflammatory Properties, H. Ozan Gülcan, Serdar Ünlü, Erden Banoğlu, M. Fethi̇ Şahi̇n, Esra Küpeli̇, Erdem Yeşi̇lada

Turkish Journal of Chemistry

In this preliminary screening study for developing potent analgesic and anti-inflammatory compounds, eight new 4-(5-chloro-2-oxo-3H-benzoxazol-3-yl)butanamide derivatives were synthesized and screened for their analgesic and anti-inflammatory activities as well as gastric ulceration potential in tested animals. Their structures were elucidated by their IR, ^{1}H-NMR and elemental analysis. All of the compounds exhibited high analgesic and anti-inflammatory activities. None of the compounds except compound 2g caused gastric lesions or bleeding in tested animals.

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Isolation And Structure Elucidation Of Novel Natural Products From Turkish Lichens, Süheyla Kirmizigül, Ömer Koz, Hüseyi̇n Anil, Siddik İçli̇, Ulvi̇ Zeybek Jan 2003

Isolation And Structure Elucidation Of Novel Natural Products From Turkish Lichens, Süheyla Kirmizigül, Ömer Koz, Hüseyi̇n Anil, Siddik İçli̇, Ulvi̇ Zeybek

Turkish Journal of Chemistry

Three natural products were isolated from three different Turkish lichens. Microbiological investigations were also examined of these lichens. Compound 1 is known as 2-hydroxy-4-methoxy-3,6-dimethyl benzoic acid, and is isolated from Pseudevernia furfuracea for the first time. Compounds 2 and 3 are detected as new compounds and called, 3-acetyl-4-amino-2-chloro-1- (4-hydroxy-2-methoxy- 6-methylphenyl carbonyloxy) benzene and 2-(4-methoxyphenyl)-2-(5-oxo-4-phenyl-2,5- dihydro-2-furaniliden) acetic acid; they were isolated from Evernia prunastri and Letharia vulpina, respectively. All these compounds had different skeletons. Their structures were established by chemical methods and spectroscopic techniques using IR, UV, 1D and 2D NMR and EI and (+) FAB-Mass methods.

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Thermogravimetric Characterization Of Turkish Bituminous Coals For Combustion, Sai̇t Kizgut, Di̇lek Cuhadaroğlu, İhsan Toroğlu Jan 2003

Thermogravimetric Characterization Of Turkish Bituminous Coals For Combustion, Sai̇t Kizgut, Di̇lek Cuhadaroğlu, İhsan Toroğlu

Turkish Journal of Chemistry

This study focused on the thermal gravimetric characterization of Turkish bituminous coals for combustion. The combustion properties considered were based on the burning profile of coal samples and their chars produced in a PL 1500 TGA apparatus. The coal seam samples used in the study were obtained from TTK (Turkish Hardcoal Enterprise) mines as channel samples. The majority of the samples from 12 seams were medium-volatile bituminous and only three of them were high-volatile bituminous. Combustion profile parameters of coal samples and chars were correlated with petrographic, proximate and ultimate analysis data in order to establish the combustion differences of …

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Differential Pulse Polarographic Determination Of Cadmium After Solid Liquid Extraction And Preconcentration Using Pan, Mohammad Ali Taher Jan 2003

Differential Pulse Polarographic Determination Of Cadmium After Solid Liquid Extraction And Preconcentration Using Pan, Mohammad Ali Taher

Turkish Journal of Chemistry

A highly selective, sensitive, rapid and economical differential pulse polarographic method has been developed for the determination of trace amounts of cadmium in various samples after the adsorption of its 1-(2-pyridylazo)-2-naphthol (PAN) complex on microcrystalline naphthalene in the pH range of 8.2-11.0. After filtration, the solid mass is shaken with 9.0 mL of 1 M hydrochloric acid and cadmium is determined by differential pulse polarography. Cadmium can alternatively be quantitatively adsorbed on [1-(2-pyridylazo)-2-naphthol]-naphthalene adsorbent packed in a column and determined similarly. The detection limit is 0.07 \mu g/mL (signal-to noise ratio = 2) and the linearity is maintained in the …

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