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- Synthesis (4)
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- Oxidation (3)
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- 1-(2-pyridylazo)-2-naphthol (1)
- 1-hydroxylinaloyl-6-O-\beta -D-glucopyranoside (1)
- 10-phenanthroline (1)
- 2 (1)
- 2-Oxo-3H-benzoxazole (1)
Articles 31 - 60 of 89
Full-Text Articles in Physical Sciences and Mathematics
Potentiometric And Spectroscopic Studies With Chromium(Iii) Complexes Of Hydroxysalicylic Acid Derivatives In Aqueous Solution, M. Suat Aksoy, Ulvi̇ye Özer
Potentiometric And Spectroscopic Studies With Chromium(Iii) Complexes Of Hydroxysalicylic Acid Derivatives In Aqueous Solution, M. Suat Aksoy, Ulvi̇ye Özer
Turkish Journal of Chemistry
The stoichiometries and stability constants of the chromium(III) complexes of hydroxysalicylic acid ligands (2,x-dihydroxy benzoic acids; 2,x-DHBA, x = 4-6)(H_3L) were determined in aqueous solution by potentiometry and spectroscopy at 25 °C and at an ionic strength of 0.1 mol L^- (KNO_3). The existence of Cr(HL)^+ type complex was verified. The stability constants of coordination species that exist in Cr(III):2,x-DHBA systems were defined. In the acidic medium the major coordination species involve salicylate type coordination. The formation of monohydroxo complexes was observed at higher pH values.
Investigation Of The Surface Acidity Of A Bentonite Modified By Acid Activation And Thermal Treatment, Tülay Alemdaroğlu, Gülcan Akkuş, Müşerref Onal, Yüksel Sarikaya
Investigation Of The Surface Acidity Of A Bentonite Modified By Acid Activation And Thermal Treatment, Tülay Alemdaroğlu, Gülcan Akkuş, Müşerref Onal, Yüksel Sarikaya
Turkish Journal of Chemistry
The adsorption of n-butylamine from its solution in cyclohexane on acid-activated and thermally treated Kütahya/Turkey bentonite (KB) samples was followed using a UV-VIS spectrophotometric method. The experimental data were evaluated by the Langmuir adsorption equation and the total number of surface acid centers (n_{m/mol} g^{-1}) was determined. The variation in n_m values as a function of the mass percent of H_2SO_4 used in activation (10%-70%) and its correlation with variations in surface area (A) and pore volume (V) as a function of the mass percent of H_2SO_4 were investigated for acid- activated KB samples. The variation in n_m values as …
Kinetics Of Oxidation Of Pyridylmethylsulphinylbenzimidazole By Cerium(Iv) In An Aqueous Perchloric Acid Medium, Dinesh C. Bilehal, Ravi̇raj M. Kulkarni, Sharanappa T. Nandibewoor
Kinetics Of Oxidation Of Pyridylmethylsulphinylbenzimidazole By Cerium(Iv) In An Aqueous Perchloric Acid Medium, Dinesh C. Bilehal, Ravi̇raj M. Kulkarni, Sharanappa T. Nandibewoor
Turkish Journal of Chemistry
The kinetics of oxidation of pyridylmethylsulphinylbenzimidazole [PMSB] by Ce(IV) in an aqueous perchloric acid medium at a constant ionic strength of 1.50 mol dm^{-3} were studied spectrophotometrically. The reaction showed first order kinetics with respect to Ce(IV) concentration and an apparent less than unit order dependence in [PMSB] and a zero order in [H^+]. The initial addition of products has no significant effect on the rate of the reaction. A possible mechanism is proposed here. The reaction constants involved in the mechanism have been computed. There is good agreement between the observed and calculated rate constants under different experimental conditions. …
The Composition Of Fatty Acids In Hypericum Scabrum, H. Scabroides And H. Amblysepalum, Hasan Çeti̇n Özen, Mehmet Başhan
The Composition Of Fatty Acids In Hypericum Scabrum, H. Scabroides And H. Amblysepalum, Hasan Çeti̇n Özen, Mehmet Başhan
Turkish Journal of Chemistry
The chemical composition of the fatty acid methyl esters (FAMEs) of flowering tops of Hypericum scabrum, H. scabroides and H. amblysepalum were identified by gas chromatography. In this work 5 FAMEs for H. scabrum, 9 FAMEs for H. scabroides and 8 FAMEs for H. amblysepalum were identified. The major components were alpha-linolenic (48.60%), linoleic (32.53%) and oleic (11.45%) acids in H. scabrum. Alpha-linolenic (29.84%), palmitic (27.90%) and oleic (16.49%) acids were present in H. scabroides and alpha linolenic (41.79%) and palmitic acids (32.28%) were found in H. amblysepalum.
Synthesis And Analgesic And Anti-Inflammatory Activity Of New Pyridazinones, Deni̇z S. Doğruer, M. Fethi̇ Şahi̇n, Esra Küpeli̇, Erdem Yeşi̇lada
Synthesis And Analgesic And Anti-Inflammatory Activity Of New Pyridazinones, Deni̇z S. Doğruer, M. Fethi̇ Şahi̇n, Esra Küpeli̇, Erdem Yeşi̇lada
Turkish Journal of Chemistry
A new series of 2-(6-oxo-3,5-diphenyl-6H-pyridazin-1-yl)- acetamides and 3-[6-oxo-3,5-diphenyl-6H-pyridazin-1-yl)-propanamides were synthesized and evaluated in terms of their analgesic and anti-inflammatory activities. All compounds except for 7g were more potent than aspirin in a p-benzoquinone--induced writhing test at 100 mg/kg dose. Compounds 7b, 7c and 7e had the highest anti-inflammatory activity; compound 7e was the most potent in terms of analgesic and anti-inflammatory activities and had no ulcerogenic side effects.
Chemical Constituents Of Campanula Lactiflora, Nuretti̇n Yayli, Nuri̇ Yildirim, Asu Usta, Serpi̇l Özkurt, Vi̇ldan Akgün
Chemical Constituents Of Campanula Lactiflora, Nuretti̇n Yayli, Nuri̇ Yildirim, Asu Usta, Serpi̇l Özkurt, Vi̇ldan Akgün
Turkish Journal of Chemistry
A new flavonoid glycoside, 4'-O-(p-hydroxybenzoyl)-isorhamnetin-3,7- di-O-\beta-D-glucopyranoside (1), and 4 known compounds, sitosterol \beta-D-glucoside (2), bis(2-ethylhexyl) adipate (3), p-hydroxybenzoic acid (4) and ethyl docosanoate (5), were isolated for the first time from Campanula lactiflora and their structures were deduced by high field 1D and 2D NMR and (+) FAB and EI mass spectra.
6-O-\Alpha-L-Rhamnopyranosylcatalpol Derivative Iridoids From Verbascum Cilicicum, İ. İrem Tatli, Zeli̇ha Ş. Akdemi̇r, Erdal Bedi̇r, Ikhlas A. Khan
6-O-\Alpha-L-Rhamnopyranosylcatalpol Derivative Iridoids From Verbascum Cilicicum, İ. İrem Tatli, Zeli̇ha Ş. Akdemi̇r, Erdal Bedi̇r, Ikhlas A. Khan
Turkish Journal of Chemistry
From the aerial parts of Verbascum cilicicum Boiss., 6 iridoid glycosides, namely catalpol (1), verbaspinoside [= 6-O-(2'' -O-trans-cinnamoyl)-\alpha-L-rhamnopyranosylcatalpol] (2), 6-O-(3''-O-trans-cinna\-moyl)-\alpha-L-rhamnopyranosylcatalpol (3), 6-O-(4''-O-trans-cinnamoyl)-\alpha -L-rhamnopyranosylcatalpol (4), saccatoside [= 6-O-(2''-O-trans-p-coumaroyl)-\alpha-L-rhamnopyranosylcatalpol] (5), and 6-O-(3''-O-trans-p-coumaroyl)-\alpha-L-rhamnopyranosylcatalpol (6), were isolated. The structures of the compounds were elucidated by means of 1 and 2 dimensional (DQF-COSY, HMQC and HMBC) NMR techniques and LC-ESIMS.
Plasticiser Effect On Water Vapour Permeability Properties Of Locust Bean Gum--Based Edible Films, Özgür Altan Bozdemi̇r, Mehmet Tutaş
Plasticiser Effect On Water Vapour Permeability Properties Of Locust Bean Gum--Based Edible Films, Özgür Altan Bozdemi̇r, Mehmet Tutaş
Turkish Journal of Chemistry
The barrier properties of edible films prepared from polysaccharide polymer (locust bean gum) and various plasticisers (glycerol, propylene glycol, sorbitol, and polyethylene glycol 200) together with hydrophobic modifiers (stearopten and beeswax) were examined. It was determined that the films containing polyethylene glycol 200 (PEG 200) and sorbitol have the lowest water vapour permeability values and the films containing glycerol have the highest WVP values. It was found that the most reasonable of the studied plasticisers was PEG 200. Polysaccharide--based edible films have higher WVP values than those of lipid-- and protein--based edible films. In order to reduce the WVP of …
Flow Injection Amperometric Determination Of Ascorbic Acid Using A Photoelectrochemical Reaction After Immobilization Of Methylene Blue On Muscovite, Yusuf Di̇lgi̇n, Zekerya Dursun, Gürel Ni̇şli̇
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 …
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
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 …
Evaluation Of Thermal Decomposition Kinetics Of Borax Pentahydrate Using Genetic Algorithm Method By Isothermal Analysis, Ömer Şahi̇n, A. Nusret Bulutcu
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 …
Characterization Of Polyphenol Oxidase From Jerusalem Artichoke (Helianthus Tuberosus), Emi̇ne Zi̇yan, Şule Pekyardimci
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 …
Flow Injection Speciation Analysis Of Manganese In Real Samples By Diphenylcarbazide-Spectrophotometric Determination, Kazem Kargosha, Meissam Noroozifar
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 …
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
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.
Gas Chromatographic Separation Of Phenol Derivatives By Schiff-Base Liquid Crystalline Stationary Phases, M. A. Ali, A. M. Al-Haideri, M. T. S. Al-Mehdawy
Gas Chromatographic Separation Of Phenol Derivatives By Schiff-Base Liquid Crystalline Stationary Phases, M. A. Ali, A. M. Al-Haideri, M. T. S. Al-Mehdawy
Turkish Journal of Chemistry
The chromatographic behaviour of liquid crystalline compounds benzylidene-p-aminobenzoic acid and 4-(p-methyl benzylidene)-p-aminobenzoic acid as stationary phases for the separation of dimethylphenol isomers was investigated. These isomers were analysed on benzylidene-p-aminobenzoic acid within a nematic range of 169-194 °C with a temperature interval of 5 °C. Better peak resolution was at a column temperature of 190 °C. The analysis was repeated on a 4-(p-methyl benzylidene)-p-aminobenzoic acid column at a nematic temperature of 256 °C, which represented the end of the nematic range, and gave the optimum peak resolution. It was found that isomer better separation was obtained at 20% loading for …
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
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 …
Crystal Structure Of Cis-Bis(N,N-Dimethyl-N'-Benzoylthioureato)Palladium(Ii), Göktürk Avşar, Hakan Arslan, Hans-Jurgen Haupt, Nevzat Külcü
Crystal Structure Of Cis-Bis(N,N-Dimethyl-N'-Benzoylthioureato)Palladium(Ii), Göktürk Avşar, Hakan Arslan, Hans-Jurgen Haupt, Nevzat Külcü
Turkish Journal of Chemistry
In this study cis-bis(N,N-dimethyl-N'-benzoylthioureato) palladium(II) is synthesised and the crystal structure is determined by X-ray diffraction methods. It crystallises in the space group P2_{1}/c, with a = 11.943(1) Å, b = 11.713(1) Å, c = 15.345(1) Å, \beta = 93.90(1)°, and D_{calc} = 1.616 g cm^{-1} for Z = 4. The Pd(II) atom is in a four-coordinate geometry consisting of two thiocarbonyl S and two carbonyl O atoms from two ligand groups. The Pd-S and Pd-O bond lengths are 2.2313(6) and 2.0211(16) Å, respectively.
Bromination Of 1-Cyclopent-1-En-1-Ylbenzene And 1-(5-Bromocyclopent-1-En-1-Yl)Benzene And Theoretical Investigation Of The Products, Mustafa Ceylan, Armağan Kinal, Yaşar Sütbeyaz, Meti̇n Balci
Bromination Of 1-Cyclopent-1-En-1-Ylbenzene And 1-(5-Bromocyclopent-1-En-1-Yl)Benzene And Theoretical Investigation Of The Products, Mustafa Ceylan, Armağan Kinal, Yaşar Sütbeyaz, Meti̇n Balci
Turkish Journal of Chemistry
The bromination of 1-cyclopent-1-en-1-ylbenzene (4) in different solvents and at different temperatures was accompanied by the evolution of hydrogen bromide and yielded 1-(5-bromocyclopent-1-en-1-yl)benzene (8). Further bromination of 8 gave exclusively 2R(S),5R(S)-1-(1,2,5-tribromocyclopentyl)benzene (11). The experimental results were compared with the theoretical ones based on semi-empirical (MM+ and AM1), Hartree-Fock (HF) and density functional theory (DFT). The formation of 11 was explained by the formation of a weakly bridged bromoniun ion of type 9.
Determination Of Manganese, Copper, Cadmium And Lead By Faas After Solid-Phase Extraction Of Their Phenylpiperazine Dithiocarbamate Complexes On Activated Carbon, Hasan Cesur
Turkish Journal of Chemistry
A solid-phase extraction method was developed for the pre-concentration of manganese, copper, cadmium and lead in water samples prior to their determination by flame atomic absorption spectrometry using phenylpiperazine dithiocarbamate as a new reagent. The optimum pre-concentration conditions have been investigated such as pH, volume of sample solution and the effects of some matrix elements. The obtained recovery was nearly 90 to 100, while the enrichment factor was 400 for metal spiked solutions.
Spectrophotometric Determination Of Iron(Ii) With 5-Nitro-6-Amino-1,10-Phenanthroline, Nebahat Demi̇rhan, Fi̇kri̇ye Tuncel Elmali
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. …
Production Of An E. Coli Toxin Protein; Colicin A In E. Coli Using An Inducible System, İsa Gökçe, Jeremy H. Lakey
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 …
Application Of A Three-Stage Sequential Extraction Procedure For The Determination Of Extractable Metal Contents In Highway Soils, Şeri̇fe Tokalioğlu, Şenol Kartal, Gökhan Bi̇rol
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 …
Effect Of Polyoxyethylene Chain Length And Electrolyte On The Viscosity Of Mixed Micelles, Hali̇de Akbaş, Tali̇ha Si̇di̇m, Mehmet İşcan
Effect Of Polyoxyethylene Chain Length And Electrolyte On The Viscosity Of Mixed Micelles, Hali̇de Akbaş, Tali̇ha Si̇di̇m, Mehmet İşcan
Turkish Journal of Chemistry
The viscosity measurements of micelles composed of mixtures of anionic/nonionic surfactants were carried out as a function of the mole fraction of surfactants. The systems studied were sodium dodecyl sulfate (SDS)-polyoxyethylene lauryl ether (C_{12}POE_{n} n = 4, 10 and 23) in water and 0.1 M sodium chloride solution. In the single systems, the relative viscosity of nonionic surfactant is greater than that of SDS, and increases with the increasing level of ethylene oxide. In the mixed surfactant systems, the relative viscosities vary at the mixed molar fraction of SDS, between 0.2 and 0.3, and then the relative viscosities of mixed …
Production Of Bacterial Polyesters From Some Various New Substrates By Alcaligenes Eutrophus And Pseudomonas Oleovorans, Hali̇l Koçer, Mehli̇ka Borcakli, Songün Demi̇rel, Baki̇ Hazer
Production Of Bacterial Polyesters From Some Various New Substrates By Alcaligenes Eutrophus And Pseudomonas Oleovorans, Hali̇l Koçer, Mehli̇ka Borcakli, Songün Demi̇rel, Baki̇ Hazer
Turkish Journal of Chemistry
Poly(3-hydroxy alkanoate)s (PHA)s are bacterial polyesters that have, due to their biodegradability and biocompatibility, attracted considerable industrial interest. All the substrates used in feeding Alcaligenes eutrophus and Pseudomonas oleovorans have been reviewed as far as we know, and some more new substrates or mixtures have been used in PHA production by microorganisms. Alcaligenes eutrophus was fed with 4-pentenoic acid, 2-hydroxy ethyl methacrylate (HEMA), corn oil acids, linseed oil acids and limonene as well as mixtures of acetic acid and glucose or lactose. Either HEMA as a sole carbon source or the mixture of glucose did not produce polyester; limonene as …
Simultaneous Determination Of Copper, Zinc And Selenium In Chicken Liver By Differential Pulse Polarography, Güler Ekmekci̇, Güler Somer, Olcay Şendi̇l
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 …
Purification And Characterization Of Glucose 6-Phosphate Dehydrogenase From Sheep Liver, Vedat Türkoğlu, Si̇nan Aldemi̇r, Mehmet Çi̇ftçi̇
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 …
Aluminum Fractionation In The Water Of Karakaya Dam Lake (Malatya, Turkey), F. Zehra Küçükbay, Mustafa Demi̇r
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 …
Dna Cleavage Activity Of Diazonium Salts: Chemical Nucleases, Murat Kizil, Ebru İnce Yilmaz, Necmetti̇n Pi̇ri̇nççi̇oğlu, Çeti̇n Ayteki̇n
Dna Cleavage Activity Of Diazonium Salts: Chemical Nucleases, Murat Kizil, Ebru İnce Yilmaz, Necmetti̇n Pi̇ri̇nççi̇oğlu, Çeti̇n Ayteki̇n
Turkish Journal of Chemistry
4-Fenoldiazonium tetrafluoroborate and 4-benzoicaciddiazonium tetrafluoroborate was prepared and was shown to be an effective DNA cleavage agent in the presence of the 1-electron donor copper(II) chloride. Its mechanism involves the generation of the aryl radical cleaving DNA by hydrogen atom abstraction from deoxyribose sugar.
^1h Nmr Studies Of Some Imidazole Ligands Coordinated To Co(Iii), Kosrow Zamani, Akbar Mobinikhaledi, Naser Foroughifar, Khalil Faghihi, Vahid Mahdavi
^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.
Synthesis And Antimicrobial Testing Of Some Flavonylsulfonamide Derivatives, Gülgün Ayhan Kilcigi̇l, Oya Bozdağ Dündar, Rahmi̇ye Ertan, Nurten Altanlar
Synthesis And Antimicrobial Testing Of Some Flavonylsulfonamide Derivatives, Gülgün Ayhan Kilcigi̇l, Oya Bozdağ Dündar, Rahmi̇ye Ertan, Nurten Altanlar
Turkish Journal of Chemistry
Six new 4-amino-N-heteroaryl,N-[(2-phenyl-4H-1-benzopyran-4- oxo-6-yl)metil]benzensulfonamide derivatives, (3a-3f) were prepared by reacting 6-bromomethylflavone with the corresponding sulfonamide derivatives and their antimicrobial activities against Escherichia coli were evaluated. All of the compounds exhibited better activity (except compound 3c) than the corresponding sulfonamide derivatives.