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2013

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The Mineralogy And Geochemistry Of Neogene Sediments From Eastern Turkey, Southeast Of Arapgir (Malatya), Di̇cle Bal Akkoca, Zeynep Baytaşoğlu Jan 2013

The Mineralogy And Geochemistry Of Neogene Sediments From Eastern Turkey, Southeast Of Arapgir (Malatya), Di̇cle Bal Akkoca, Zeynep Baytaşoğlu

Turkish Journal of Earth Sciences

The mineralogy and geochemistry of volcaniclastic sediments in the southeastern part of the Arapgir area (Malatya) were studied by optical microscopy, XRD, SEM, ICP-AES, and MS techniques. Samples were collected from the marine and lacustrine deposits of the Dibekli and Böğürlüdağ sections that contained calcite, clay minerals, feldspar, quartz, dolomite, and opal. Clay minerals were mixed layer smectite-chlorite, illite, and palygorskite, with Ca-smectite being the dominant clay phase. Smectite was derived from the transformation of volcanic glass and volcanic rock fragments. The fact that Y, Sc, Co and \SigmaREE concentrations and (La/Lu)N, La/Sc, Sc/Th, Co/Th, Th/U, and Zr/Hf ratios of …

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Preliminary Geoelectrical Identification Of A Low-Temperature Hydrothermal System In The Anzer Glacial Valley, İkizdere, Rize, Turkey, Abdullah Karaman Jan 2013

Preliminary Geoelectrical Identification Of A Low-Temperature Hydrothermal System In The Anzer Glacial Valley, İkizdere, Rize, Turkey, Abdullah Karaman

Turkish Journal of Earth Sciences

The Anzer glacial valley, at an elevation of over 2300 m in the Eastern Black Sea region of Turkey, exhibits evidence for a low-temperature hydrothermal system (40-100 °C). Low-temperature hydrothermal systems usually do not receive attention since they are not useful for energy production. However, in areas where natural beauty is prominent, as in the Anzer valley, such resources can easily trigger investment for all-season resorts that significantly contribute to the economy. In this study, we examine the site evidence and carry out self-potential and dc-resistivity sounding surveys using a Schlumberger electrode configuration. The resistivity cross-section obtained from the inversion …

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Coastal Inundation Due To Sea Level Rise And Extreme Sea State And Its Potential Impacts: Çukurova Delta Case, Özlem Si̇mav, Dursun Zafer Şeker, Cem Gazi̇oğlu Jan 2013

Coastal Inundation Due To Sea Level Rise And Extreme Sea State And Its Potential Impacts: Çukurova Delta Case, Özlem Si̇mav, Dursun Zafer Şeker, Cem Gazi̇oğlu

Turkish Journal of Earth Sciences

With the rising sea level becoming a more pressing issue to coastal areas, a comprehensive analysis has been conducted to assess the vulnerability of the Çukurova Delta under the projected inundation by the end of the century. The level of inundation was estimated from a multimission satellite altimetry sea level anomaly and significant wave height data between September 1992 and February 2012. Superposed to the clear annual oscillation with 6.2 cm amplitude peaking around the beginning of October, the mean sea level signal exhibits a positive trend of 3.4 ± 0.1 mm/year over the altimetric data period. The extreme wave …

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Cover And Contents Jan 2013

Cover And Contents

Turkish Journal of Earth Sciences

No abstract provided.

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Central Anatolian Plateau, Turkey: Incision And Paleoaltimetry Recorded From Volcanic Rocks, Erkan Aydar, Hüseyi̇n Evren Çubukçu, Erdal Şen, Lütfi̇ye Akin Jan 2013

Central Anatolian Plateau, Turkey: Incision And Paleoaltimetry Recorded From Volcanic Rocks, Erkan Aydar, Hüseyi̇n Evren Çubukçu, Erdal Şen, Lütfi̇ye Akin

Turkish Journal of Earth Sciences

The erosion/incision patterns of radiometrically well-constrained volcanic rocks provide excellent markers for revealing the landscape evolution. The Central Anatolian High Plateau represents an uplifted area that reaches up to 1500 m above sea level and includes the Cappadocian Volcanic Province (CVP). The CVP is composed of horizontally emplaced Neogene-Quaternary ignimbrites intercalated with lava flows and epiclastic continental sediments. River incision rates have been calculated using the morphological/paleoaltimetric features of radiometrically well-constrained volcanic units in the area. Starting from 10 Ma until 5 Ma, there was no major erosion or incision. The morphology, uplift rate, and incision rates of the CVP …

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Palaeoenvironmental And Chronological Constraints On The Tuğlu Formation (Çankırı Basin, Central Anatolia, Turkey), Ilaria Mazzini, Natalia Hudáková, Peter Joniak, Marianna Kovacova, Tamás Mikes, Andreas Mulch, Fuat Bora Rojay, Stella Lucifora, Daniela Esu, Ingeborg Soulie-Marsche Jan 2013

Palaeoenvironmental And Chronological Constraints On The Tuğlu Formation (Çankırı Basin, Central Anatolia, Turkey), Ilaria Mazzini, Natalia Hudáková, Peter Joniak, Marianna Kovacova, Tamás Mikes, Andreas Mulch, Fuat Bora Rojay, Stella Lucifora, Daniela Esu, Ingeborg Soulie-Marsche

Turkish Journal of Earth Sciences

The Çankırı Basin, located in the northern part of the Central Anatolian Plateau, is a large Tertiary basin where thick Miocene to Quaternary continental sediments overlay the Cretaceous-Tertiary units. This investigation focuses on the Tuğlu Formation, an Upper Miocene succession mainly composed of dark grey silty and organic rich clays. The type section of Tuğlu has been sampled for an array of multidisciplinary analyses. The palaeontological proxies included ostracod, foraminifer, nannoplankton, pollen, molluscs, charophytes, small mammal assemblages, fish, and crab remains. The abiotic parameters studied were: palaeomagnetism and environmental magnetism, stable carbon and oxygen isotope ratios (on ostracods and bulk …

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Paleomagnetic Rotations In The Late Miocene Sequence From The Çankırı Basin (Central Anatolia, Turkey): The Role Of Strike-Slip Tectonics, Stella Lucifora, Francesca Cifelli, Fuat Bora Rojay, Massimo Mattei Jan 2013

Paleomagnetic Rotations In The Late Miocene Sequence From The Çankırı Basin (Central Anatolia, Turkey): The Role Of Strike-Slip Tectonics, Stella Lucifora, Francesca Cifelli, Fuat Bora Rojay, Massimo Mattei

Turkish Journal of Earth Sciences

In this paper, new paleomagnetic and anisotropy of magnetic susceptibility (AMS) data from Miocene continental units of the Çankırı Basin are presented, with the main goal of providing additional constraints on its deformational and rotational history during the Late Cenozoic. AMS data indicate a tectonic origin for the magnetic fabric, suggesting that Upper Miocene units were still involved in the deformation processes. Paleomagnetic data show that tectonic rotations in the Çankırı Basin do not show a symmetrical distribution along the opposite edges of the basin, as expected from the observed omega-shape. In particular, by combining our data with those already …

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Stable Isotope-Based Reconstruction Of Oligo-Miocene Paleoenvironment And Paleohydrology Of Central Anatolian Lake Basins (Turkey), Tina Lüdecke, Tamás Mikes, Fuat Bora Rojay, Michael A. Cosca, Andreas Mulch Jan 2013

Stable Isotope-Based Reconstruction Of Oligo-Miocene Paleoenvironment And Paleohydrology Of Central Anatolian Lake Basins (Turkey), Tina Lüdecke, Tamás Mikes, Fuat Bora Rojay, Michael A. Cosca, Andreas Mulch

Turkish Journal of Earth Sciences

Isotope geochemistry of lacustrine carbonate represents a powerful tool to reconstruct paleoclimatic and paleoenvironmental conditions. Here, we present a comprehensive set of long-term oxygen (delta^{18}O) and carbon (delta^{13}C) stable isotope records from 5 Chattian to Burdigalian lacustrine sequences distributed over the Central Anatolian Plateau. Field relationships combined with stable isotope geochemistry indicate a relatively humid subtropic Late Oligocene climate with an environment characterized by large, temporally open freshwater lakes. Approximately during the middle Aquitanian, a 4%o-5%o increase in lake delta^{18}O values indicates changes in regional climate including more arid conditions and an increasing dominance of closed saline lake conditions in …

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Cenozoic Tectonics Of The Tuz Gölü Basin (Central Anatolian Plateau, Turkey), David Fernández-Blanco, Giovanni Bertotti, Tahsi̇n Atti̇la Çi̇ner Jan 2013

Cenozoic Tectonics Of The Tuz Gölü Basin (Central Anatolian Plateau, Turkey), David Fernández-Blanco, Giovanni Bertotti, Tahsi̇n Atti̇la Çi̇ner

Turkish Journal of Earth Sciences

We present a new 3D geologic model for the architecture and Cenozoic tectonic evolution of the Tuz Gölü Basin, a major sedimentary basin in the Central Anatolian orogenic plateau. This model is grounded on 7 depth-converted seismic reflection profiles in combination with the analysis of backstripped subsidence curves, isochore maps, and a palinspastically restored cross-section. Two stages of basin formation are detected during Cenozoic times. During the Palaeogene, around 2 km of basement subsidence led to the development of a sag basin broader than the present basin in the absence of bounding faults. After a period of uplift and erosion, …

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Middle-Upper Miocene Paleogeography Of Southern Turkey: Insights From Stratigraphy And Calcareous Nannofossil Biochronology Of The Olukpınar And Başyayla Sections (Mut-Ermenek Basin), Paola Cipollari, Eva Halásová, Kemal Gürbüz, Domenico Cosentino Jan 2013

Middle-Upper Miocene Paleogeography Of Southern Turkey: Insights From Stratigraphy And Calcareous Nannofossil Biochronology Of The Olukpınar And Başyayla Sections (Mut-Ermenek Basin), Paola Cipollari, Eva Halásová, Kemal Gürbüz, Domenico Cosentino

Turkish Journal of Earth Sciences

The age of the marine succession capping the basement rocks of the central Taurides in the Mut-Ermenek Basin is constrained using calcareous nannofossil biochronology. The Olukpınar section, which correlates with the biozones between MNN5a and MNN6b (late Langhian-late Serravallian), represents a deeper marine environment developed lateral to the Ermenek platform. The long-term transgressive-regressive cycle of the Olukpınar section, which corresponds to the middle-upper part of the TB2 supercycle, can be subdivided into 2 large-scale (10^6 years) cycles (TB2.4 and TB2.5) based on the occurrence of 2 major debris flow deposits linked to sea-level drop. The younger late Tortonian Başyayla section …

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Circum-Tethyan Carbonate Platform Evolution During The Palaeogene: The Prebetic Platform As A Test For Climatically Controlled Facies Shifts, Stefan Höntzsch, Christian Scheibner, Johannes P. Brock, Jochen Kuss Jan 2013

Circum-Tethyan Carbonate Platform Evolution During The Palaeogene: The Prebetic Platform As A Test For Climatically Controlled Facies Shifts, Stefan Höntzsch, Christian Scheibner, Johannes P. Brock, Jochen Kuss

Turkish Journal of Earth Sciences

The distribution of selected shallow-benthic biota at circum-Tethyan carbonate platforms demonstrates an excellent proxy for the impact of latitudinally controlled cooling and variations in the trophic resources during the Palaeogene. In this study, we link and compare the spatial distribution and abundance of larger benthic foraminifera and hermatypic corals of Tethyan carbonate successions with new records from the Prebetic platform in SE Spain. The succession of the Prebetic platform is dominated by larger benthic foraminifera and coralline red algae throughout the Eocene, whereas corals were not recorded until the Late Eocene. Similar biotic trends were reported from 10 selected circum-Tethyan …

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Impact Of Pb-Zn Mining Activity On Surficial Sediments Of Lake Kalimanci(Fyr Macedonia), Petra Vrhovnik, Nastja Rogan Smuc, Tadej Dolenec, Todor Serafimovski, Matej Dolenec Jan 2013

Impact Of Pb-Zn Mining Activity On Surficial Sediments Of Lake Kalimanci(Fyr Macedonia), Petra Vrhovnik, Nastja Rogan Smuc, Tadej Dolenec, Todor Serafimovski, Matej Dolenec

Turkish Journal of Earth Sciences

The activities of the Sasa mine have led to industrial discharge being released into Lake Kalimanci since the beginning of mining activity in 1954. For this reason, an ecological risk assessment is urgently required. In the present study, surficial lake sediments were analyzed using inductively coupled plasma mass spectrometry (ICP-MS), with all geochemistry data processed using Statistica 8. In order to assess the environmental pollution status, 2 environmental factors were established, while for the determination of chemical fractionation of toxic metals a sequential extraction procedure was carried out. Concentrations of As, Mo, Zn, Ni, Co, Pb, Cd, and Cu in …

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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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