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2013

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Computation Of Grade Values Of Sediment-Hosted Barite Deposits In Northeastern Isparta (Western Turkey), Numan Elmas, Uğur Şahi̇n Jan 2013

Computation Of Grade Values Of Sediment-Hosted Barite Deposits In Northeastern Isparta (Western Turkey), Numan Elmas, Uğur Şahi̇n

Turkish Journal of Earth Sciences

Grade value is a crucial parameter for the mineral industry. Investigation of grade value of mineral resources provides the optimum benefit. In this study, an adaptive neuro-fuzzy inference system (ANFIS) and artificial neural network (ANN) model were applied for the prediction of grade values. The spatial coordinates X, Y, and Z of the study area along with bore hole geochemical data were used as input variables in the model. In order to illustrate the applicability and capability of these methods, the western part of Turkey, between the latitudes 38°01 45 N and 38°09 52 N and between the longitudes 31°23 …

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Cover And Contents Jan 2013

Cover And Contents

Turkish Journal of Earth Sciences

No abstract provided.

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Dorothy Perry Thompson Papers - Accession 1352, Dorothy Perry Thompson Jan 2013

Dorothy Perry Thompson Papers - Accession 1352, Dorothy Perry Thompson

Manuscript Collection

Dr. Dorothy Perry Thompson was a Winthrop professor of English and an accomplished poet and writer. As well as teaching in the English Department, Dr. Thompson also coordinated the African American Studies program which she helped found. The Dorothy Perry Thompson Papers consists of her poems and writings, drafts, research, notes, contract agreements, awards and certificates, speaking engagement flyers and records, thank you letters, and promotion and tenure records.

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South Carolina Association Of Family And Consumer Sciences Records - Accession 180, Family And Consumer Sciences, South Carolina Association Of Jan 2013

South Carolina Association Of Family And Consumer Sciences Records - Accession 180, Family And Consumer Sciences, South Carolina Association Of

Manuscript Collection

This South Carolina Association of Family and Consumer Sciences Records (SCAFCS) is a valuable source on Family and Consumer Science history in South Carolina during the twentieth and twenty-first centuries. The organization was known as the South Carolina Home Economics Association (SCHEA) from 1914 to 1995. This collection contains records created by the organization, including correspondence, meeting agendas and minutes, reports, handbooks, financial records, newsletters, constitution and by-laws, newspaper clippings, photographs, and memorabilia, as well as information about the organization’s annual meeting, various committees within the organization and the College Club Section of the organization. There is also a reference …

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Alice Henrietta Gregg Papers - Accession 312, Alice Henrietta Gregg Jan 2013

Alice Henrietta Gregg Papers - Accession 312, Alice Henrietta Gregg

Manuscript Collection

Dr. Alice Henrietta Gregg (1893-1978) was a 1914 graduate of Winthrop College and she served as a Christian missionary to China from 1916 to 1950. The Alice Henrietta Gregg Papers in box one primarily consist of dissertation notes on Chinese culture, pamphlets, & magazines relating to China, a dedication book, drawings, pictures, a portfolio of Indian art, and a scrapbook (1950-1967) which contains some correspondence and biographical information. The collection in box 2 primarily consist of Dr. Alice Gregg’s bible, a copy of her book titled: Hsin Hsin Yin; Hearts Touch Hearts, a book titled: Fifty Years in China, The …

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Fabrication Of Layer-By-Layer Deposited Films Containing Carbon Nanotubes And Poly(Malachite Green) As A Sensor For Simultaneous Determination Of Ascorbic Acid, Epinephrine, And Uric Acid, Jahan Bakhsh Raoof, Reza Ojani, Mehdi Baghayeri Jan 2013

Fabrication Of Layer-By-Layer Deposited Films Containing Carbon Nanotubes And Poly(Malachite Green) As A Sensor For Simultaneous Determination Of Ascorbic Acid, Epinephrine, And Uric Acid, Jahan Bakhsh Raoof, Reza Ojani, Mehdi Baghayeri

Turkish Journal of Chemistry

A simple approach to constructing a double-layer voltammetric sensor is described. The poly(malachite green) (PMG) and multiwalled carbon nanotubes (MWCNTs) were coimmobilized at the surface of the glassy carbon electrode (GCE) for fabrication of PMG/MWCNT/GCE. The modified electrode was characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), differential pulse voltammetry (DPV), and chronoamperometric techniques. Using DPV, the obtained catalytic peak current was linearly dependent on the ascorbic acid (AA), epinephrine (EP), and uric acid (UA) concentrations in the ranges of 0.4-100.0, 0.1-100.0, and 0.3-90.0 \muM, respectively. The resultant detection limits for AA, EP, and UA were 0.23, 0.0820, and …

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A New Method For Calculating The Vibration-Rotation-Tunneling Spectra Of Molecular Clusters And Its Application To The Water Dimer, Mahi̇r Erteki̇n Ocak Jan 2013

A New Method For Calculating The Vibration-Rotation-Tunneling Spectra Of Molecular Clusters And Its Application To The Water Dimer, Mahi̇r Erteki̇n Ocak

Turkish Journal of Chemistry

A new method is developed for calculating the vibration-rotation-tunneling spectra of molecular clusters consisting of rigid monomers. The method is based on generation of optimized bases for each monomer. First, a sequential symmetry adaptation procedure is developed for relating the symmetries of monomer basis functions with the symmetries of the eigenstates of the cluster. Then this symmetry adaptation procedure is used in the generation of optimized bases and combining them for finding the eigenstates. Symmetry adaptation problems related to the generation of optimized bases are identified and solutions are suggested. The method is applied to the water dimer by using …

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Disposable Carbon Electrodes As An Alternative For The Direct Voltammetric Determination Of Alkyl Phenols From Water Samples, Iulia Gabriela David, Irinel Adriana Badea, Gabriel Lucian Radu Jan 2013

Disposable Carbon Electrodes As An Alternative For The Direct Voltammetric Determination Of Alkyl Phenols From Water Samples, Iulia Gabriela David, Irinel Adriana Badea, Gabriel Lucian Radu

Turkish Journal of Chemistry

Disposable sensors based on a pencil graphite electrode were described for detection of alkyl phenols. The performances of the disposable bare pencil graphite electrode (PGE) and PGE modified with carbon nanotubes, regarding the cyclic and differential pulse voltammetric determination of 4-nonylphenol, 4-octylphenol, and 4-tert-octylphenol, were compared. Some experimental variables of the electrode surface pretreatment and measurement parameters were optimized. Using a phosphate buffer solution (pH 7.40) as the supporting electrolyte, alkyl phenols gave a well-defined oxidation peak at about 700 mV vs. Ag/AgCl. The detection limits established for each alkyl phenol were: 0.25 \muM for 4-octylphenol, 0.42 \muM for 4-nonylphenol, …

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Synthesis And Characterization Of Ni(Ii) And Cu(Ii) Complexes Derived From Novel Phenolic Mannich Bases, Nurgün Büyükkidan, Sali̇h Özer Jan 2013

Synthesis And Characterization Of Ni(Ii) And Cu(Ii) Complexes Derived From Novel Phenolic Mannich Bases, Nurgün Büyükkidan, Sali̇h Özer

Turkish Journal of Chemistry

The novel phenolic Mannich bases 2,2'-(2-hydroxy-4,5- dimethylbenzylazanediyl)diethanol (1) and 2-((2-(4-(2-hydroxy-4,5- dimethylbenzyl)piperazin-1-yl)ethylamino)methyl)-4,5-dimethylphenol (2) have been synthesized in good yield by using a microwave-induced technique from 3,4-dimethylphenol and corresponding amines in the presence of formaldehyde. Metal complexes of 1 and 2 for Ni(II) (3 and 5) and for Cu(II) (4 and 6) have also been prepared and all compounds have been characterized by elemental and spectral analyses. Thermal, magnetic, and electronic studies have also been reported for metal complexes. Electronic spectra and magnetic susceptibility measurements suggested tetrahedral geometry for Ni(II) (3), square planar geometry for Cu(II) (4) complexes of 1, and octahedral …

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Molecular Docking And Qsar Study On Imidazole Derivatives As 14 /Alpha -Demethylase Inhibitors, Asghar Davood, Maryam Iman Jan 2013

Molecular Docking And Qsar Study On Imidazole Derivatives As 14 /Alpha -Demethylase Inhibitors, Asghar Davood, Maryam Iman

Turkish Journal of Chemistry

14\alpha-Demethylase (CYP51) inhibitors have been widely used in the treatment of fungal infections. In this study, a series of imidazole derivatives with CYP51 inhibitory activity were subjected to a molecular docking study followed by quantitative structure-activity relationship (QSAR) analyses in search of the ideal physicochemical characteristics of potential CYP51 inhibitors. Desired imidazoles were built using the HyperChem program, and conformational studies were performed through a semiempirical method followed by the PM3 method. Docking study was performed using the AutoDock program on all of the compounds. Different QSAR descriptors were calculated using DRAGON, AutoDock, and HyperChem. Multilinear regression was used as …

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Enaminonitriles In Heterocyclic Synthesis: Synthesis And Biological Evaluation Of Novel Indeno[2,1-B]Thiophene Derivatives, Ahmed A. Fadda, Abd El Galil M. Khalil, Eman H. Tawfik Jan 2013

Enaminonitriles In Heterocyclic Synthesis: Synthesis And Biological Evaluation Of Novel Indeno[2,1-B]Thiophene Derivatives, Ahmed A. Fadda, Abd El Galil M. Khalil, Eman H. Tawfik

Turkish Journal of Chemistry

No abstract provided.

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Synthesis, Characterization, And Swelling Behaviors Of A Ph-Responsive Cmc-G-Poly(Aa-Co-Amps) Superabsorbent Hydrogel, Yizhe Wang, Xiaoning Shi, Wenbo Wang, Aiqin Wang Jan 2013

Synthesis, Characterization, And Swelling Behaviors Of A Ph-Responsive Cmc-G-Poly(Aa-Co-Amps) Superabsorbent Hydrogel, Yizhe Wang, Xiaoning Shi, Wenbo Wang, Aiqin Wang

Turkish Journal of Chemistry

New superabsorbent hydrogels were synthesized through free radical graft copolymerization of partially neutralized acrylic acid (AA) and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) onto carboxymethyl cellulose (CMC) backbones. The structure and morphology of the synthesized superabsorbent hydrogels were characterized by Fourier transform infrared spectroscopy and scanning electron microscope. The effect of the molar ratio of AMPS to AA, the APS concentration, and the CMC content on swelling ratio was optimized. The swelling properties in various pH solutions and saline solutions as well as the swelling kinetics were also evaluated. Results showed that the introduction of AMPS enhanced the swelling capacity, swelling rate, and …

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Spectrophotometric Determination Of 3-Hydroxy-3-Methylglutaryl Coenzyme-A Reductase Inhibitors In Pharmaceutical Preparations, Gamze Ergi̇n, Sena Çağlar, Armağan Önal, Sidika Ertürk Toker Jan 2013

Spectrophotometric Determination Of 3-Hydroxy-3-Methylglutaryl Coenzyme-A Reductase Inhibitors In Pharmaceutical Preparations, Gamze Ergi̇n, Sena Çağlar, Armağan Önal, Sidika Ertürk Toker

Turkish Journal of Chemistry

Simple and accurate spectrophotometric methods are presented for the determination of five 3-hydroxy-3-methylglutaryl coenzyme-A (HMG-CoA) reductase inhibitors (statins), namely atorvastatin, fluvastatin, pitavastatin, rosuvastatin, and simvastatin, in pharmaceutical preparations. The methods are based on the reaction of drugs as n-electron donor with 7,7,8,8-tetracyanoquinodimethane as \pi-acceptors to give highly colored complex species. All variables were studied in order to optimize the reaction conditions. Beer's law was obeyed in the concentration ranges 4--20 \mu g mL^{-1}, 4--12 \mu g mL^{-1}, 0.8--2.4 \mu g mL^{-1}, 4--14 \mu g mL^{-1}, and 2.5--20 \mu g mL^{-1} for atorvastatin, fluvastatin, pitavastatin, rosuvastatin, and simvastatin, respectively. The proposed …

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Antimicrobial Activity And Chemical Composition Of The Essential Oils Of Mosses (Hylocomium Splendens (Hedw.) Schimp. And Leucodon Sciuroides (Hedw.) Schwägr.) Growing In Turkey, Tayyi̇be Beyza Cansu, Büşra Yayli, Turan Özdemi̇r, Nevzat Batan, Şengül Alpay Karaoğlu, Nuretti̇n Yayli Jan 2013

Antimicrobial Activity And Chemical Composition Of The Essential Oils Of Mosses (Hylocomium Splendens (Hedw.) Schimp. And Leucodon Sciuroides (Hedw.) Schwägr.) Growing In Turkey, Tayyi̇be Beyza Cansu, Büşra Yayli, Turan Özdemi̇r, Nevzat Batan, Şengül Alpay Karaoğlu, Nuretti̇n Yayli

Turkish Journal of Chemistry

In the present work, the volatiles of mosses [Hylocomium splendens (Hedw.) Schimp. (Hylocomiaceae) and Leucodon sciuroides (Hedw.) Schwägr. (Leucodontaceae)] have been investigated by GC-FID and GC/MS. Fifty-eight compounds in the oil of H. splendens, representing 75.4%, and 41 compounds in the oil of L. sciuroides, representing 87.6%, were identified. The major components were found to be \beta-pinene (11.6%) and \alpha-pinene (8.9%) in the oil of H. splendens, and nonanal (26.8%) and heptanal (13.7%) in the oil of L. sciuroides. The essential oil of H. splendens was rich in monoterpenes (30.8%), and aldehydes (49.9%) were the major constituents in the oil …

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Study On Crystal Transformation Process Of Magnesium Carbonate Hydrate Based On Salt Lake Magnesium Resource Utilization, Juan Du, Zhen Chen, Yulong Wu, Mingde Yang, Jie Dang, Jianjun Yuan Jan 2013

Study On Crystal Transformation Process Of Magnesium Carbonate Hydrate Based On Salt Lake Magnesium Resource Utilization, Juan Du, Zhen Chen, Yulong Wu, Mingde Yang, Jie Dang, Jianjun Yuan

Turkish Journal of Chemistry

The crystal transformation process of magnesium carbonate hydrate by the reaction of magnesium sulfate (MgSO_4) with ammonium carbonate [(NH_4)_2CO_3] was investigated. MgSO_4 is one of the main magnesium resources of the Lop Nur salt lake in the Xinjiang Autonomous Region of China. Magnesium carbonate hydrates with different chemical compositions were prepared. The transformation process of the 2 crystals, MgSO_4 and (NH_4)_2CO_3, was analyzed by Raman spectroscopy, and the associated changes in crystal morphology were observed by scanning electron microscopy. The needle-like MgCO_3 \cdot 3H_2O transformed into sheet-like 4MgCO_3 \cdot Mg(OH)_2 \cdot 4H_2O when the temperature was increased from 323 K …

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Synthesis And Characterization Of New Chromogenic Substrates For Exoglycosidases: \Alpha-Glucosidase, \Alpha-Mannosidase, And \Beta-Galactosidase, Dumitru Petru Iga, Richard Schmidt, Silvia Iga, Corina Loredana Hotoleanu, Florentina Duica, Alina Nicolescu, Silvia Stefania Gitman Jan 2013

Synthesis And Characterization Of New Chromogenic Substrates For Exoglycosidases: \Alpha-Glucosidase, \Alpha-Mannosidase, And \Beta-Galactosidase, Dumitru Petru Iga, Richard Schmidt, Silvia Iga, Corina Loredana Hotoleanu, Florentina Duica, Alina Nicolescu, Silvia Stefania Gitman

Turkish Journal of Chemistry

Glycosides of 4-nitrocatechol (1,2-dihydroxy 4-nitrobenzene) with \alpha-D-glucopyranose and \alpha-D-mannopyranose were synthesized by the glycosylation of phenol with peracetylated sugars in the presence of BF_3\cdot OBu_2. The glycoside of 4-nitrocatechol with \beta-D-galactopyranose was prepared by the glycosylation of this phenol as sodium phenoxide with tetra-O-benzoyl-\alpha-D- galactopyranosyl bromide. The structure of the reaction products was confirmed by ^1 H and ^{13}C NMR spectra and by chemical analysis. The latter consisted of acidic hydrolysis, followed by ethyl ether extraction and colorimetric determination of 4-nitrocatechol in the ether phase and application of the anthrone method for the sugar in the water phase. The synthetic …

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Potentiometric Determination Of Some Food Additives And Their Binding To A Polycationic Species Using Polyion Sensors, Nedi̇me Dürüst, Ali̇ Kayansalan Jan 2013

Potentiometric Determination Of Some Food Additives And Their Binding To A Polycationic Species Using Polyion Sensors, Nedi̇me Dürüst, Ali̇ Kayansalan

Turkish Journal of Chemistry

Polycation-sensitive membrane electrodes based on dinonylnaphthalene sulfonate (DNNS) were examined for the determination of some polyanions, namely xanthan (Xanth), alginate (Alg), carboxymethyl cellulose (CMC), and carrageenan (Carr). The potentiometric titrations of polyanionic analytes yielded sharp end points and correlative stoichiometries. After the determinations were successfully performed in saline, these polyanions were also determined in some food products consumed in Bolu (Turkey). In addition, the titration data were used to estimate the interactions between titrant and polyanionic analytes. The equilibrium constants, K_{eq}, and the number of titrant binding sites (n) per mole of analyte polyanion were calculated using Scatchard plots. The …

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Theoretical Study On The Addition Reaction Between Propadienylidene And Methyleneimine, Mengyuan Wang, Yungang Chen, Shanshan Ding, Yingde Wang, Qianchao Cao, Xiaojun Tan, Jinsong Gu Jan 2013

Theoretical Study On The Addition Reaction Between Propadienylidene And Methyleneimine, Mengyuan Wang, Yungang Chen, Shanshan Ding, Yingde Wang, Qianchao Cao, Xiaojun Tan, Jinsong Gu

Turkish Journal of Chemistry

The reaction mechanism between propadienylidene and methyleneimine was systematically investigated employing the second-order Møller--Plesset perturbation theory (MP2) method with the 6 -- 31 + G* basis set. Geometry optimization, vibrational analysis, and energy property of the involved stationary points on the potential energy surface were calculated. The energies of the different species were corrected by single point energy calculations at the CCSD (T) // MP2 / 6 -- 31 + G* level. From the surface energy profile, one important initial intermediate characterized by a 3-membered ring structure was located via a transition state firstly. After that, 3 different products possessing …

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Adsorption Equilibrium Of Water Vapor On Activated Carbon And Alumina And Carbon And Alumina Impregnated With Hygroscopic Salt, Ioan Solomon, Ana Mafalda Ribeiro, Joao Carlos Santos, Jose Miguel Loureiro, Alirio E. Rodrigues, Ion Sandu, Ioan Mamaliga Jan 2013

Adsorption Equilibrium Of Water Vapor On Activated Carbon And Alumina And Carbon And Alumina Impregnated With Hygroscopic Salt, Ioan Solomon, Ana Mafalda Ribeiro, Joao Carlos Santos, Jose Miguel Loureiro, Alirio E. Rodrigues, Ion Sandu, Ioan Mamaliga

Turkish Journal of Chemistry

The adsorption equilibrium of water vapor on different adsorbent materials has been studied. Small grains of commercial activated carbon and alumina, with a diameter of d_g = 1.5 \times 10^{-3} m, were impregnated with a hygroscopic salt (calcium chloride) to improve the performance of these materials. The main characteristics of the new composite materials were obtained by adsorption/desorption of nitrogen at 77 K and salt distribution on the adsorbent surface was shown using scanning electron microscopy. The adsorption equilibrium isotherms of water vapor were measured by a gravimetric system at 2 different temperatures in the case of alumina and impregnated …

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Establishment Of An Electrochemical Rna Aptamer-Based Biosensor To Trace Nanomolar Concentrations Of Codeine, Mehdi Saberian, Davoud Asgari, Yadollah Omidi, Jaleh Barar, Hossein Hamzeiy Jan 2013

Establishment Of An Electrochemical Rna Aptamer-Based Biosensor To Trace Nanomolar Concentrations Of Codeine, Mehdi Saberian, Davoud Asgari, Yadollah Omidi, Jaleh Barar, Hossein Hamzeiy

Turkish Journal of Chemistry

Codeine is an opium alkaloid with a great potential of abuse among opioid consumers. Detection of codeine is a routine procedure in the military and government of some countries for personnel recruitment. Therefore, a specific, selective, and easy to use method would be an important improvement in such detection procedures. According to previous reports, short single-stranded DNA or RNA sequences with high affinity and specificity to their targets, aptamers, could be used for designing an accurate and specific biosensor for codeine. This study introduces an aptamer-based biosensor for codeine detection in nanomolar concentrations by an electrochemical method, and ferrocene carboxylic …

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New Synthetic Strategy For Novel 6-Arylazo-5-Methyl-3-Aryl-Thiazolo[2,3-C]- [1,2,4]Triazoles And Study Of Their Solvatochromic Properties, Ahmad Sami Shawali, Mohie Eldin Moustafa Zayed Jan 2013

New Synthetic Strategy For Novel 6-Arylazo-5-Methyl-3-Aryl-Thiazolo[2,3-C]- [1,2,4]Triazoles And Study Of Their Solvatochromic Properties, Ahmad Sami Shawali, Mohie Eldin Moustafa Zayed

Turkish Journal of Chemistry

Two series of 6-arylazothiazol[2,3-c][1,2,4]triazoles were prepared via oxidative cyclization of the respective aldehyde N-(5-arylazo-4-methylthiazol-2-yl)-hydrazones. The structures of the latter hydrazone precursors and the azo compounds were confirmed by spectral and elemental analyses. The solvatochromism of the title azo dyes is evaluated by means of the Kamlet--Taft equation and discussed.

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Synthesis, Spectroscopic Characterization, And Genotoxicity Of A New Group Of Azo-Oxime Metal Chelates, Beyza Cabi̇r, Bariş Avar, Mehmet Gülcan, Ahmet Kayraldiz, Mükerrem Kurtoğlu Jan 2013

Synthesis, Spectroscopic Characterization, And Genotoxicity Of A New Group Of Azo-Oxime Metal Chelates, Beyza Cabi̇r, Bariş Avar, Mehmet Gülcan, Ahmet Kayraldiz, Mükerrem Kurtoğlu

Turkish Journal of Chemistry

A new azo-oxime ligand, 2-[(E)-(hydroxyimino)methyl]-4-[(E)- (4-nitrophenyl)diazenyl]phenol, (pxoxH_2) (2), was prepared by condensation of hydroxylamminehydrochloride and 2-hydroxy5- [(4-nitrophenyl)diazenyl]benzaldehyde (1) with treatment of a solution of diazonium salt of p-nitroaniline and 2-hydroxybenzaldehyde in ethanol. The 6 coordination compounds, [Mn(pxoxH)_2(H_2O)_2].H_2O (3), [Co(pxoxH)_2(H_2O)_2].4H_2O (4), [Ni(pxoxH)_2(H_2O)_2].2H_2O (5), [Cu(pxoxH)_2].H_2O (6), [Zn(pxoxH)_2].6H_2O (7), and [Cd(pxoxH)_2(H_2O)_2].H_2O (8), were prepared by reacting Mn(II), Ni(II) Cu(II), Co(II), Zn(II), and Cd(II) ions with the ligand. The structures of the compounds were elucidated from the elemental analysis data and spectroscopic studies. The azo-oxime metal complexes were also characterized by XRD, magnetic moment, molar conductivity, and thermal analyses. Elemental analyses of the chelates …

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Potentiometric Study Of Equilibrium Constants Of A Novel Triazine--Thione Derivative And Its Stability Constants With Hg^{2+}, Cu^{2+}, Ni^{2+}, Pb^{2+}, And Zn^{2+} Metal Ions In Ethanol And Water Mixed, Fati̇h Polat, Hasan Atabey, Hayati̇ Sari, Alaaddi̇n Çukurovali Jan 2013

Potentiometric Study Of Equilibrium Constants Of A Novel Triazine--Thione Derivative And Its Stability Constants With Hg^{2+}, Cu^{2+}, Ni^{2+}, Pb^{2+}, And Zn^{2+} Metal Ions In Ethanol And Water Mixed, Fati̇h Polat, Hasan Atabey, Hayati̇ Sari, Alaaddi̇n Çukurovali

Turkish Journal of Chemistry

The deprotonation constants of 5-hydroxy-5,6-di-pyridin-2-yl-4,5-dihydro-2H-[1,2,4] triazine-3-thione (HPT) and the stability constants of its Hg^{2+}, Ni^{2+}, Cu^{2+}, Pb^{2+}, and Zn^{2+} ion complexes were studied in 20% ethanol and water mixed at 25 \pm 0.1 °C and ionic strength (I) of 0.1 M supported by NaCl. Four pK_a values of HPT were determined: 3.58, 6.30, 9.23, and 9.69. In various pH conditions, the different complex forms were formulated as ML, MHL, MH_2L, MH_3L, MH_4L, and MH_{-2}L between Hg^{2+}, Ni^{2+}, Cu^{2+}, Pb^{2+}, and Zn^{2+} ions and HPT. According to the potentiometric and spectrophotometric results, the HPT and Hg^{2+} combination formed a selective and …

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Flavonoid Constituents Of Sideritis Caesarea, Belkis Halfon, Ece Çi̇ftçi̇, Gülaçti Topçu Jan 2013

Flavonoid Constituents Of Sideritis Caesarea, Belkis Halfon, Ece Çi̇ftçi̇, Gülaçti Topçu

Turkish Journal of Chemistry

The acetone extract of the aerial parts of Sideritis caesarea Duman, Aytaç & Başer (Lamiaceae) afforded the flavonoids penduletin (1) and apigenin (2) and 6 glycosylated flavonoids, 4'-O-methyl-isoscutellarein-7-O-[6'''-O-acetyl-\beta-D-allopyranosyl- (1 \to 2)]-6\"-O-acetyl-\beta -D-glucopyranoside (3), 4'-O-methylhypolaetin- 7-O-[6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]-6\"-O-acetyl-\beta- D-glucopyranoside (4), isoscutellarein-7-O-[6'''-O-acetyl-\beta- D-allopyranosyl-(1 \to 2)]-6\"-O-acetyl-\beta -D-glucopyranoside (5), isoscutellarein-7-O-[6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]- \beta-D-glucopyranoside (6), 4'-O-methylhypolaetin-7-O- [6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]-\beta-D- glucopyranoside (7), and hypolaetin-7-O-[6'''-O-acetyl-\beta- D-allopyranosyl-(1 \to 2)]-\beta -D-glucopyranoside (8). The compounds were identified by the use of 1D- and 2D-NMR and UV spectroscopic techniques and by comparisons with the reported data. The acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities of the acetone, methanol, …

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Quasielastic Light Scattering Studies Of Polypeptides: Evidence For Chain Extension In Solution, Mehmet Bahatti̇n Baysal, Çi̇ğdem Karadağ Jan 2013

Quasielastic Light Scattering Studies Of Polypeptides: Evidence For Chain Extension In Solution, Mehmet Bahatti̇n Baysal, Çi̇ğdem Karadağ

Turkish Journal of Chemistry

Dynamic light scattering and viscosimetric methods were used to study polypeptides including polyleucine, poly (\gamma-benzyl-L-glutamate), poly (\alpha-L-glutamic acid), and polyproline II. Chain extension showing rod-like and flexible conformations occurred in poly(\gamma -benzyl-L-glutamate) and polyproline II solutions as these solutions were diluted in glacial acetic acid or in a mixed solvent of acetic acid and dichloromethane. The elongation of chains in poly(\gamma -benzyl-L-glutamate) and polyproline II solutions was studied by dynamic light scattering and viscosimetric methods. This nonenzymatic growth of peptide chains provides data on primordial synthesis of protein molecules in the absence of cell machinery and for this reason these …

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An Expedient Synthesis Of 6-Vinylfulvene, İhsan Erden, Jenny Sabol, Ana Gubeladze, Andrea Ruiz Jan 2013

An Expedient Synthesis Of 6-Vinylfulvene, İhsan Erden, Jenny Sabol, Ana Gubeladze, Andrea Ruiz

Turkish Journal of Chemistry

6-Vinylfulvenes constitute a class of fulvenes that are difficult to access due to the lack of a general method for their synthesis. In particular, the unsubstituted parent system has been very difficult to obtain by existing methods. In this communication we describe a convenient 3-step protocol for the synthesis of the title compound by way of sulfide oxidation and subsequent sulfoxide elimination.

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An Amphipathic Thioxanthone-Anthracene Photoinitiator For Free-Radical Polymerization, Deni̇z Tunç Beyazit, Burçi̇n Gacal, Yusuf Yağci Jan 2013

An Amphipathic Thioxanthone-Anthracene Photoinitiator For Free-Radical Polymerization, Deni̇z Tunç Beyazit, Burçi̇n Gacal, Yusuf Yağci

Turkish Journal of Chemistry

A novel thioxanthone-anthracene (TX-A) photoinitiator possessing an octyl group, TX-A-Oct, as amphipathic photoinitiator was synthesized by click chemistry. Its ability to initiate photopolymerization of various monomers, namely methyl methacrylate (MMA), acryl amide (Am), butyl acrylate (BA), styrene (St), and a multifunctional monomer trimethylolpropane triacrylate (TMPTA), was examined in both the presence and absence of air. TX-A-Oct was found to be effective in initiating polymerization also in the absence of a co-initiator. UV, FTIR, and fluorescence spectroscopic analysis and polymerization studies revealed that depending on the conditions photoinitiations occur through both anthracene and thioxanthone chromophoric groups by hydrogen abstraction and endoperoxide …

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Anticholinesterase Furocoumarins From Heracleum Platytaenium, A Species Endemic To The Ida Mountains, Demet Di̇ncel, Seda Damla Hatipoğlu, Ahmet Ceyhan Gören, Gülaçti Topçu Jan 2013

Anticholinesterase Furocoumarins From Heracleum Platytaenium, A Species Endemic To The Ida Mountains, Demet Di̇ncel, Seda Damla Hatipoğlu, Ahmet Ceyhan Gören, Gülaçti Topçu

Turkish Journal of Chemistry

The petroleum ether extract of Heracleum platytaenium afforded 8 furocoumarins (psoralen, bergapten, xanthotoxin, pimpinellin, isopimpinellin, sphondin, byakangelicin, and heraclenol) and the methanol extract of H. platytaenium gave only 1 glycosylated dihydrofurocoumarin, apterin. In addition, stigmasterol was also obtained from petroleum ether extract. Structure identification of the isolated compounds has been achieved by using spectroscopic methods, namely 1D and 2D NMR experiments and mass spectral analyses. The antioxidant activity of the extracts and pure compounds was investigated by 2 methods, including DPPH free radical scavenging activity and lipid peroxidation inhibitory activity by \beta-carotene-linoleic acid assays. The anticholinesterase activity of petroleum ether …

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Cover And Contents Jan 2013

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

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Determination Of Zineb In Tap Water And Tomato Samples By Adsorptive Catalytic Stripping Voltammetry, Özlem Karakoç, Nuri̇ Naki̇boğlu Jan 2013

Determination Of Zineb In Tap Water And Tomato Samples By Adsorptive Catalytic Stripping Voltammetry, Özlem Karakoç, Nuri̇ Naki̇boğlu

Turkish Journal of Chemistry

This paper describes a sensitive and accurate adsorptive catalytic stripping voltammetric method for the determination of zineb (zinc ethylene-bis- dithiocarbamate) in tap water and tomato samples. The method is based on the reduction of adsorbed zineb at a hanging mercury drop electrode following its catalytic oxidation using peroxydisulfate as an oxidizing reagent. Chemical and instrumental parameters of the process were optimized. The catalytic mechanism of the reduction of zineb is discussed as well. The limits of detection (3 s) and quantification (10 s) and linear range of the method for accumulation time of 60 s were calculated as 8.1 nM, …

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