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2016

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Mineralogy, Geochemistry, And Depositional Environment Of The Beduh Shale(Lower Triassic), Northern Thrust Zone, Iraq, Faraj Tobia, Sirwa Shangola Jan 2016

Mineralogy, Geochemistry, And Depositional Environment Of The Beduh Shale(Lower Triassic), Northern Thrust Zone, Iraq, Faraj Tobia, Sirwa Shangola

Turkish Journal of Earth Sciences

Integrated mineralogical and geochemical methods are utilized to investigate the provenance, paleoweathering, and depositional setting of shale from the Lower Triassic Beduh Formation in the Northern Thrust Zone, Iraq. The ~64-m-thick Beduh Formation consists of calcareous shale and marl intercalations with thin calcareous sandstone interbeds. X-ray diffraction analysis revealed that clay minerals comprise illite, kaolinite, and chlorite, with a minor mixed layer of illite/smectite and illite/chlorite. Calcite and quartz are the main nonclay species with subordinate amounts of feldspar and hematite. The mineralogical and geochemical parameters of the shale (e.g., high content of illite and moderate illite crystallinity index, Al2O3/TiO2, …

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Mineral Chemistry Of Igneous Rocks In The Lar Cu-Mo Prospect, Southeastern Part Of Iran: Implications For P, T, And ƒO2, Rahele Moradi, Mohammad Boomeri, Sasan Bagheri, Kazuo Nakashima Jan 2016

Mineral Chemistry Of Igneous Rocks In The Lar Cu-Mo Prospect, Southeastern Part Of Iran: Implications For P, T, And ƒO2, Rahele Moradi, Mohammad Boomeri, Sasan Bagheri, Kazuo Nakashima

Turkish Journal of Earth Sciences

The Lar Cu-Mo prospect is located 20 km north of Zahedan in Sistan and Baluchestan Province. This area is geologically situated in the Sistan Suture Zone. The Cu-Mo mineralization occurs as silicic veins in the Lar igneous rocks and includes hypogene chalcopyrite, bornite, and molybdenite mineralization. The syenite to monzonite host rocks occur as stock and dyke and display granular to porphyritic texture. In this study, mineral chemistry and petrographic examination of igneous rocks are used to constrain the crystallization conditions of the magma. The compositional range of plagioclase is relatively narrow (0.11%-26.05% An), whereas that of potassium feldspar is …

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Distribution Of Natural Radioactivity And Assessment Of Radioactive Dose Of Western Anatolian Plutons, Turkey, Argyrios Papadopoulos, Şafak Altunkaynak, Antonis Koroneos, Alp Ünal, Ömer Kamaci Jan 2016

Distribution Of Natural Radioactivity And Assessment Of Radioactive Dose Of Western Anatolian Plutons, Turkey, Argyrios Papadopoulos, Şafak Altunkaynak, Antonis Koroneos, Alp Ünal, Ömer Kamaci

Turkish Journal of Earth Sciences

The distribution of 226Ra, 232Th, and 40K in 70 granite samples obtained from 13 Western Anatolian plutons (Turkey) was measured by using γ-ray spectroscopy. The activities of the measured radionuclides varied up to 259 Bq kg-1 for 226Ra, up to 241 Bq kg?1 for 232Th, and up to 2518 Bq kg-1 for 40K, with mean values of 66 (±44), 90 (±47), and 1097 (±410) Bq kg-1, respectively, which are smaller than the mean values given for granites worldwide. The mean value of the increase on the external γ-radiation effective dose rate is 0.21 (±0.09) mSv year-1, varying by <1 mSv year-1. The mean value of the internal α-radiation was 0.15 (±0.10) mSv year-1, varying <0.5 mSv year-1. Most of the samples cause an increase to both the external and internal dose by <30%, which is smaller than the permitted limit. Therefore, there is no radiological risk from the usage of the samples studied as decorative and ornamental building materials.

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A New Pelagic Conodont Taxon Of The Central Pontides (Turkey), Ali̇ Murat Kiliç Jan 2016

A New Pelagic Conodont Taxon Of The Central Pontides (Turkey), Ali̇ Murat Kiliç

Turkish Journal of Earth Sciences

The Hallstatt-type limestones in the Central Pontides yield abundant conodonts of the genus Gladigondolella ranging throughout the entire studied sequence and indicating Anisian to Early Carnian ages. Gladigondolella okayi n. sp. is described.

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Organic Geochemistry And Element Distribution In Coals Formed In Eocene Lagoon Facies From The Eastern Black Sea Region, Ne Turkey, Çi̇ğdem Saydam Eker, İbrahi̇m Akpinar, Ferkan Si̇pahi̇ Jan 2016

Organic Geochemistry And Element Distribution In Coals Formed In Eocene Lagoon Facies From The Eastern Black Sea Region, Ne Turkey, Çi̇ğdem Saydam Eker, İbrahi̇m Akpinar, Ferkan Si̇pahi̇

Turkish Journal of Earth Sciences

The amount and type, the inorganic element content, and the maturity of organic materials of Eocene coals, shaly coals, and coaly shales exposed in the Gümüşhane and Bayburt districts of the Eastern Black Sea Region of Turkey were investigated. The depositional environments and hydrocarbon potentials were also interpreted. The total organic carbon concentrations in the studied samples ranged from 0.50% to 63.08%. The samples from Özyurt, Kayadibi, and Tarhanas contained types II and III kerogen, and those from Sökmen and Manas contained type III kerogen. The samples contained Co, Cs, Ga, Hf, Th, U, Y, Mo, Be, Cd, Sb, and …

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Geochemistry And C, O, And Sr Isotope Composition Of The Föderata Group Metacarbonates (Southern Veporicum, Western Carpathians, Slovakia):Constraints On The Nature Of Protolith And Its Depositional Environment, Marek Vdacny, Peter Ruzicka, Anna Vozarova Jan 2016

Geochemistry And C, O, And Sr Isotope Composition Of The Föderata Group Metacarbonates (Southern Veporicum, Western Carpathians, Slovakia):Constraints On The Nature Of Protolith And Its Depositional Environment, Marek Vdacny, Peter Ruzicka, Anna Vozarova

Turkish Journal of Earth Sciences

Major, trace, and rare earth element as well as C, O, and Sr isotope geochemistry is used to provide new insights into the characteristics and depositional environment of the protolith of the Föderata Group metacarbonates in the southern Veporicum cover sequence (Western Carpathians, Slovakia). The metacarbonates are characterized by high LOI and CaO and by small contents of various insoluble components. Among the trace elements investigated, only As, Ba, Co, Cu, Hg, Nb, Ni, Pb, Rb, Sb, Sr, Th, U, Y, Zn, and Zr display concentrations beyond their detection limits. The metacarbonates are strongly depleted in Rb, Ba, Th, Nb, …

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Geochemical Characterization And Palynological Studies Of Some Agbada Formation Deposits Of The Niger Delta Basin: Implications For Paleodepositional Environments, Olajide Femi Adebayo, Segun Ajayi Akinyemi, Henry Yemagu Madukwe, Adeyinka Oluyemi Aturamu, Adebayo Olufemi Ojo Jan 2016

Geochemical Characterization And Palynological Studies Of Some Agbada Formation Deposits Of The Niger Delta Basin: Implications For Paleodepositional Environments, Olajide Femi Adebayo, Segun Ajayi Akinyemi, Henry Yemagu Madukwe, Adeyinka Oluyemi Aturamu, Adebayo Olufemi Ojo

Turkish Journal of Earth Sciences

Forty-two ditch cutting samples of the KR-1 offshore well from depths of 9660 ft to 10,920 ft composited at 90-ft intervals were subjected to sedimentological, micropaleontological, and geochemical analyses using standard procedures and the laser ablation-induced coupled plasma mass spectrometry technique, respectively. Sedimentological analysis revealed the presence of glauconites and the rare occurrence of framboidal pyrites, indicative of deposition in a slightly anoxic marine environment. Palynomorph percentage distribution shows that there are more terrestrially derived miospores (dominated by Zonocostites ramonae (Rhizophora spp.), Psilatricolporites crassus (Tabernaemontana crassa), Acrotichum aureum, and Laevigatosporites sp.) than marine phytoplanktons. Rare occurrence of Globoquadrina venezuelana, Globigerinoides …

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Clay Mineralogy And Geochemistry Of Three Offshore Wells In The Southwestern Black Sea, Northern Turkey: The Effect Of Burial Diagenesis On The Conversion Of Smectite To Illite, Yi̇nal Neşes Huvaj, Warren D. Huff Jan 2016

Clay Mineralogy And Geochemistry Of Three Offshore Wells In The Southwestern Black Sea, Northern Turkey: The Effect Of Burial Diagenesis On The Conversion Of Smectite To Illite, Yi̇nal Neşes Huvaj, Warren D. Huff

Turkish Journal of Earth Sciences

The conversion of smectite to illite has long been studied by numerous researchers because of its importance as a diagenetic metric. Interpreting the pressure, temperature, and age of the sequences in which this conversion occurs provides the possibility to identify the historical maturation parameters of hydrocarbon sources. The Black Sea Basin is known to be an area that can provide source rocks for oil and gas production. The purpose of this study was to determine the clay minerals and their abundances, to establish a stratigraphic correlation among three wells, which is useful to select specific stratigraphic horizons for hydrocarbon exploration, …

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Monitoring Voip Speech Quality For Chopped And Clipped Speech, Andrew Hines, Jan Skoglund, Anil C. Kokaram, Naomi Harte Jan 2016

Monitoring Voip Speech Quality For Chopped And Clipped Speech, Andrew Hines, Jan Skoglund, Anil C. Kokaram, Naomi Harte

Articles

No abstract provided.

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A New Educational Mobile Devices Platform For Social Inclusion In Tanzania, Fredrick Mtenzi Jan 2016

A New Educational Mobile Devices Platform For Social Inclusion In Tanzania, Fredrick Mtenzi

Articles

Abstract— It is evident that advances in technology has led to improvement in societal wellbeing. In this paper we demonstrate how mobile phones are used in providing reliable and quality education to students in disadvantaged areas of Tanzania. The main contribution is on leveraging on the success that Tanzania has had on using mobile banking to the un-banked population. These lessons are adapted to the education sector, where clever/smart integration of existing disruptive technologies such as mobile phones and social networks are be used to provide access to high quality educational contents. Further, the paper shows how educational content can …

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Face Recognition-Based Real-Time System For Surveillance, Fahad Parvez Mahdi, Md. Mahmudul Habib, Susan Mckeever, A.S.M. Moslehuddin, Pandian Vasant Jan 2016

Face Recognition-Based Real-Time System For Surveillance, Fahad Parvez Mahdi, Md. Mahmudul Habib, Susan Mckeever, A.S.M. Moslehuddin, Pandian Vasant

Articles

The ability to automatically recognize human faces based on dynamic facial images is important in security, surveillance and the health/independent living domains. Specific applications include access control to secure environments, identification of individuals at a particular place and intruder detection. This research proposes a real-time system for surveillance using cameras. The process is broken into two steps: (1) face detection and (2) face recognition to identify particular persons. For the first step, the system tracks and selects the faces of the detected persons. An efficient recognition algorithm is then used to recognize detected faces with a known database. The proposed …

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Synthetic Protocols On 6$H$-Benzo[$C$]Chromen-6-Ones: A Review, Ofentse Mazimba Jan 2016

Synthetic Protocols On 6$H$-Benzo[$C$]Chromen-6-Ones: A Review, Ofentse Mazimba

Turkish Journal of Chemistry

6$H$-Benzo[$c$]chromen-6-ones serve as core structures of secondary metabolites and are of considerable pharmacological importance. Natural sources produce limited quantities, hence the need for synthetic procedures for 6$H$-benzo[$c$]chromen-6-ones, which are herein reviewed. The literature describes protocols such as the Suzuki coupling reactions for the synthesis of biaryl, which then undergoes lactonization, reactions of 3-formylcoumarin (chromenones) with 1,3-bis(silylenol ethers), radical mediated cyclization of arylbenzoates, metal or base catalyzed cyclization of phenyl-2-halobenzoates and 2-halobenzyloxyphenols, and benzoic acid coupling with benzoquinone using electrophilic metal-based catalyst. The efficient and simple procedures are those involving the reactions of Michael acceptor (chromenones and chalcones) with 1,3- and …

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Characterization And Photocatalytic Properties Of Tio$_{2}$/Chitosan Nanocomposites Synthesized By Hydrothermal Process, Funda Okuşluk, Fatma Bi̇lge Emre Jan 2016

Characterization And Photocatalytic Properties Of Tio$_{2}$/Chitosan Nanocomposites Synthesized By Hydrothermal Process, Funda Okuşluk, Fatma Bi̇lge Emre

Turkish Journal of Chemistry

Nanocomposites of TiO$_{2}$/chitosan (nTC) were synthesized by hydrothermal process at 200 $^{\circ}$C. Photocatalytic activity of the nanocomposites was studied with degradation of malachite green (MG) in aqueous medium. Structural and physico-chemical properties of the obtained nanocomposites were characterized by XRD, SEM, BET, FTIR, and particle size analyzer. Complete photodegradation of MG was successfully achieved with the aid of the nanocomposites. The optimum photocatalytic degradation conditions, irradiation time, irradiation power, and amount of catalyst were studied. Photocatalytic activity of the synthesized nanocomposites in terms of degradation of MG was compared with that of undoped TiO$_{2}$ (synthesized by our team) and chitosan …

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Synthesis And Evaluation Of A Novel N--P-Containing Oil-Based Fire-Retardant Plasticizer For Poly(Vinyl Chloride), Pu-You Jia, Guo-Dong Feng, Yun Hu, Yong-Hong Zhou Jan 2016

Synthesis And Evaluation Of A Novel N--P-Containing Oil-Based Fire-Retardant Plasticizer For Poly(Vinyl Chloride), Pu-You Jia, Guo-Dong Feng, Yun Hu, Yong-Hong Zhou

Turkish Journal of Chemistry

A novel N--P-containing soybean-oil-based fire-retardant plasticizer was synthesized using soybean oil methyl ester, 9,10-dihydro-9-oxa-phosphaphenanthrene-10-oxide (DOPO), and tris(2-hydroxyethyl) isocyanurate (THEIC). The structure was verified by Fourier transform infrared (FTIR) spectrometry and nuclear magnetic resonance (NMR) spectroscopy. The blends were characterized by thermogravimetric analysis (TGA), FTIR spectrometry, scanning electron microscopy (SEM), and dynamic mechanical analysis (DMA). TGA showed that the thermal stability of the blends were acceptable. DMA indicated that the plasticizer had good plasticity for PVC. The limiting oxygen index (LOI) of the blends ranged from 21.3 to 29.6. The flammability and thermal stability of PVC/THEIC-DOPO-ESOME was better than that of …

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Comparative Study For The Separation, Preconcentration, And Determination Of Copper And Cadmium In Real Samples By Using Two Different Ligands, Hami̇de Elvan Bayrak, Volkan Numan Bulut, Mehmet Tüfekçi̇, Hacer Bayrak, Celal Duran, Mustafa Soylak Jan 2016

Comparative Study For The Separation, Preconcentration, And Determination Of Copper And Cadmium In Real Samples By Using Two Different Ligands, Hami̇de Elvan Bayrak, Volkan Numan Bulut, Mehmet Tüfekçi̇, Hacer Bayrak, Celal Duran, Mustafa Soylak

Turkish Journal of Chemistry

Two new solid phase extraction methods have been developed for simultaneous separation and preconcentration of Cu(II) and Cd(II) in some food and environmental samples before their determination by flame atomic absorption spectrometry (FAAS). One of these methods is based on the absorption of the Cu(II) and Cd(II) complexes with [3-(cyanomethyl)-5-(4-methylphenyl)-4$H$-1,2,4-triazol-4-yl]carbamate (L1) and the other is based on the absorption of the Cu(II) and Cd(II) complexes with 4-(4-methylphenyl)-5-{[pyridine-4-yl-4$H$-1,2,4-triazole-3-yl)thio]methyl}-4$H$-1,2,4-triazole-3-thiol (L2) on Amberlite XAD-1180 resin. The metal complexes are retained on resin at pH 6.0 and eluted with 1.0 mol L$^{-1}$ HCl in acetone in both methods. After the optimum conditions were determined, …

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Square Wave Voltammetric Determination Of Valproic Acid In Pharmaceutical Preparations, Ebru Türköz Acar, Ati̇ye Nur Onar Jan 2016

Square Wave Voltammetric Determination Of Valproic Acid In Pharmaceutical Preparations, Ebru Türköz Acar, Ati̇ye Nur Onar

Turkish Journal of Chemistry

The electrochemical behavior of valproic acid (VAL) was investigated using square wave voltammetry, cyclic voltammetry, and sampled direct current polarography and a new square wave voltammetric method was developed for determination of VAL in pharmaceutical preparations. VAL showed two reduction peaks at about --0.2 V and --0.8 V vs. Ag/AgCl 3 M KCl with a hanging mercury drop electrode in 0.05 M pH 3.3 Britton--Robinson (BR) buffer. These peaks were named peak I and peak II, respectively. The types of limiting current of both peaks were determined as diffusion controlled based on cyclic voltammetry studies. A linear calibration graph was …

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Durability Of Carbon/Conducting Polymer Composite Supported Pt Catalysts Prepared By Supercritical Carbon Dioxide Deposition, Gamze Bozkurt, Fulya Memi̇oğlu, Ayşe Bayrakçeken Yurtcan Jan 2016

Durability Of Carbon/Conducting Polymer Composite Supported Pt Catalysts Prepared By Supercritical Carbon Dioxide Deposition, Gamze Bozkurt, Fulya Memi̇oğlu, Ayşe Bayrakçeken Yurtcan

Turkish Journal of Chemistry

Polypyrrole (PPy)/carbon (C) composites were synthesized by oxidative chemical polymerization and used as support material for Pt nanoparticles. PPy/C supported Pt nanoparticles were prepared by using a promising catalyst preparation method, supercritical carbon dioxide (scCO$_{2})$ deposition. The prepared materials were characterized by using BET, TGA, XRD, and TEM techniques. Cyclic voltammetry was used in order to determine the electrocatalytic activity of the prepared catalyst for hydrogen oxidation and oxygen reduction reactions that occur in proton exchange membrane fuel cells (PEMFCs). The Pt loading obtained over the composite material was around 10{\%}. TEM results showed highly dispersed and small nanoparticles over …

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Sentiment Classification Using Negation As A Proxy For Negative Sentiment, Bruno Ohana, Brendan Tierney, Sarah Jane Delany Jan 2016

Sentiment Classification Using Negation As A Proxy For Negative Sentiment, Bruno Ohana, Brendan Tierney, Sarah Jane Delany

Conference papers

We explore the relationship between negated text and neg- ative sentiment in the task of sentiment classification. We propose a novel adjustment factor based on negation occur- rences as a proxy for negative sentiment that can be applied to lexicon-based classifiers equipped with a negation detec- tion pre-processing step. We performed an experiment on a multi-domain customer reviews dataset obtaining accuracy improvements over a baseline, and we further improved our results using out-of-domain data to calibrate the adjustment factor. We see future work possibilities in exploring nega- tion detection refinements, and expanding the experiment to a broader spectrum of opinionated …

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Voltammetric Determination Of Famotidine On A Disposable Pencil Graphite Electrode, Iulia Gabriela David, Dana Elena Popa, Andreea-Alexandra Calin, Mihaela Buleandra, Emilia-Elena Iorgulescu Jan 2016

Voltammetric Determination Of Famotidine On A Disposable Pencil Graphite Electrode, Iulia Gabriela David, Dana Elena Popa, Andreea-Alexandra Calin, Mihaela Buleandra, Emilia-Elena Iorgulescu

Turkish Journal of Chemistry

The present paper describes the use of a disposable pencil graphite electrode (PGE) for the voltammetric determination of famotidine. Cyclic voltammetric studies using different supporting electrolytes emphasized an irreversible oxidation of famotidine on the PGE. The electrode process is diffusion-controlled and pH-dependent. Differential pulse voltammetry (DPV) in phosphate buffer solution of pH 6.81 was employed for famotidine's quantitative determination. The anodic peak current of famotidine varies linearly with the analyte concentration in the range 4.72 $\times $ 10$^{-7}$--4.95 $\times $ 10$^{-4}$ M. Detection and quantification limits were 1.51 $\times $ 10$^{-7}$ M and 5.04 $\times $ 10$^{-7}$ M famotidine, respectively. …

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Adsorptive Features Of Polyacrylamide--Aluminosilicate Composites For Methylene Blue, Demet Baybaş, Ulvi̇ Ulusoy Jan 2016

Adsorptive Features Of Polyacrylamide--Aluminosilicate Composites For Methylene Blue, Demet Baybaş, Ulvi̇ Ulusoy

Turkish Journal of Chemistry

Polyacrylamide--montmorillonite (PAAm-Mt) and polyacrylamide--clinoptilolite (PAAm-Z) composites were prepared by cross-linked polymerization of acrylamide in dispersions of Mt and Z. The composites were characterized by FT-IR, SEM, XRD, CEC, and PZC analysis. The adsorptive features of PAAm-Mt and PAAm-Z for methylene blue (MB) were investigated by their relevance to initial dye concentration, temperature, contact time, PZC, and pH. The monolayer adsorption capacities were 0.14 and 0.08 mol kg$^{-1}$ for PAAm-Z and PAAm-Mt, respectively. The changes in pH of MB solution had an insignificant influence on their adsorption capacities. The values of enthalpy and entropy changes were positive ($\Delta $H$_{PAAm-Mt}$ = 7.6 …

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Liquid State $^{15}$N Nmr Studies Of $^{15}$N Isotope Labeled Phthalocyanines, Armağan Atsay, Ahmet Gül, Makbule Koçak Jan 2016

Liquid State $^{15}$N Nmr Studies Of $^{15}$N Isotope Labeled Phthalocyanines, Armağan Atsay, Ahmet Gül, Makbule Koçak

Turkish Journal of Chemistry

$^{15}$N labeled soluble metallo- and metal-free phthalocyanines are described for the first time. The complexes were synthesized starting from phthalic anhydride derivatives using 98{\%} $^{15}$N enriched urea. The effects of the substitution pattern, aggregation, and coordinated metal on $^{15}$N chemical shifts in liquid state NMR were studied.

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A Convenient Route For The Synthesis Of New Thiadiazoles, Abdelwahed Sayed, Yasser Zaki, Emad Aish Jan 2016

A Convenient Route For The Synthesis Of New Thiadiazoles, Abdelwahed Sayed, Yasser Zaki, Emad Aish

Turkish Journal of Chemistry

The present work describes the preparation of new thiadiazoles through a simple intramolecular reaction of mono- and bis-hydrazonoyl halides with methyl hydrogen phenyl carbonimidodithioate or methyl-2-arylidene hydrazinecarbodithioate. The synthetic method involves nucleophilic substitution followed by intramolecular cyclization reactions mediated by evolution of methanethiol. The structures of the title compounds were elucidated by elemental analyses, and FTIR, MS and NMR spectra.

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Wittig--Horner Reagents: Powerful Tools In The Synthesis Of 5-And 6-Heterocyclic Compounds; Shedding Light On Their Application In Pharmaceutical Chemistry, Rizk Elsayed Khidre, Wafaa Mahmoud Abdou Jan 2016

Wittig--Horner Reagents: Powerful Tools In The Synthesis Of 5-And 6-Heterocyclic Compounds; Shedding Light On Their Application In Pharmaceutical Chemistry, Rizk Elsayed Khidre, Wafaa Mahmoud Abdou

Turkish Journal of Chemistry

This paper reviews literature over 25 years' activity on phosphoryl carbanion reagents and shows that these compounds are powerful tools in organic chemistry. The main target of this review is to outline some of the reactive peculiarities that make this class of compounds powerful tools in the synthesis of 5- and 6-heterocyclic compounds and/or substituted heterocycle phosphor esters. The importance of these latter compounds in pharmacology is also discussed.

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Synthetic Approaches Towards The Synthesis Of Beta-Blockers (Betaxolol, Metoprolol, Sotalol, And Timolol), Furqan Ahmad Saddique, Ameer Fawad Zahoor, Muhammmad Yousaf, Muhammmad Irfan, Matloob Ahmad, Asim Mansha, Zulfiqar Ali Khan, Syed Ali Raza Naqvi Jan 2016

Synthetic Approaches Towards The Synthesis Of Beta-Blockers (Betaxolol, Metoprolol, Sotalol, And Timolol), Furqan Ahmad Saddique, Ameer Fawad Zahoor, Muhammmad Yousaf, Muhammmad Irfan, Matloob Ahmad, Asim Mansha, Zulfiqar Ali Khan, Syed Ali Raza Naqvi

Turkish Journal of Chemistry

Numerous efficient synthetic methodologies have been elaborated for the synthesis of $\beta $-blockers since the introduction of propranolol (a beta-blocker) in 1968. In this review, focus is placed on the more concise asymmetric and bioenzymatic synthetic approaches attempted towards the synthesis of beta-blockers (betaxolol, metoprolol, sotalol, and timolol).

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Immobilization Of Laccase Onto A Porous Nanocomposite: Application For Textile Dye Degradation, Sedef İlk, Deni̇z Demi̇rcan, Semran Sağlam, Necdet Sağlam, Zakir M. O. Rzayev Jan 2016

Immobilization Of Laccase Onto A Porous Nanocomposite: Application For Textile Dye Degradation, Sedef İlk, Deni̇z Demi̇rcan, Semran Sağlam, Necdet Sağlam, Zakir M. O. Rzayev

Turkish Journal of Chemistry

Poly(MA-\textit{alt}-MVE)-$g$-PLA/ODA-MMT nanocomposite was prepared by self-catalytic interlamellar graft copolymerization of L-lactic acid (LA) onto poly(maleic anhydride-\textit{alt}-methyl vinyl ether) copolymer in the presence of octadecyl amine-montmorillonite (ODA-MMT) organoclay. FTIR, $^{1}$H ($^{13}$C) NMR, XRD, and SEM-TEM were utilized for characterizing the resultant nanocomposite. Laccase from \textit{Trametes versicolor} was immobilized onto the prepared nanocomposite by adsorption or covalent coupling. Decolorization of Reactive Red 3 from aqueous solution by laccase immobilized on the nanocomposite was studied in different conditions (pH, temperature, dye concentration, and reaction time) to investigate the decolorization activity with repeated use and storage. The results indicated that more than 77{\%} of …

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The Role Of N-Heterocyclic Carbene Substituents On Ruthenium(Ii) Complexes In The Catalytic Transfer Hydrogenation Of Acetophenone, Muhammet Emi̇n Günay, Gülcan Gençay Çoğaşlioğlu Jan 2016

The Role Of N-Heterocyclic Carbene Substituents On Ruthenium(Ii) Complexes In The Catalytic Transfer Hydrogenation Of Acetophenone, Muhammet Emi̇n Günay, Gülcan Gençay Çoğaşlioğlu

Turkish Journal of Chemistry

The novel ruthenium(II) complexes [RuCl$_{2}$(NHC)($p$-cymene)], \textbf{3a}--\textbf{e}, containing 1-alkyl-3-benzylimidazol-2-ylidene ligands were prepared. All synthesized compounds were characterized by NMR spectroscopy and elemental analyses. Ru(II)-NHC complexes were tested as catalysts for the transfer hydrogenation of acetophenone, showing modest to high activity in this reaction. The results revealed that efficiencies depend on the substituents of the benzene ring of the benzyl on the N atom of the NHC ring.

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Enhanced Delivery Of Epirubicin By Polyoxometalate-Based Magnetic Nanocarriers: Controlled Drug Loading And Ph-Sensitive Drug Release, Ezzat Rafiee, Nasibeh Rahpeyma Jan 2016

Enhanced Delivery Of Epirubicin By Polyoxometalate-Based Magnetic Nanocarriers: Controlled Drug Loading And Ph-Sensitive Drug Release, Ezzat Rafiee, Nasibeh Rahpeyma

Turkish Journal of Chemistry

A series of polyoxometalate-based magnetic nanoparticles were developed as novel carriers for anticancer drugs. Characterization of the nanoparticles was done by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), wavelength dispersive X-ray (WDX), and laser particle size analyzer. Epirubicin (EPI) was selected as a model drug. EPI loading efficiency, EPI loading content, and EPI release profiles were studied. Drug loading was controlled using acid-base titration since H$^{+}$ was released during the loading process. Based on these investigations, an efficient EPI delivery system was introduced. It showed high EPI-loading capacity (35.2 wt.{\%}) and high EPI loading …

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Oxidative Dehydrogenation Of Propane Over V$_{2}$O$_{5}$ And K$_{2}$O-V$_{2}$O$_{5}$ Impregnated Mgal$_{2}$O$_{4}$Catalysts, Serkan Naci̇ Koç, Kübra Dayioğlu, Hasan Özdemi̇r Jan 2016

Oxidative Dehydrogenation Of Propane Over V$_{2}$O$_{5}$ And K$_{2}$O-V$_{2}$O$_{5}$ Impregnated Mgal$_{2}$O$_{4}$Catalysts, Serkan Naci̇ Koç, Kübra Dayioğlu, Hasan Özdemi̇r

Turkish Journal of Chemistry

V$_{2}$O$_{5}$ and K$_{2}$O-V$_{2}$O$_{5}$ impregnated MgAl$_{2}$O$_{4}$ catalysts were prepared and tested for the oxidative dehydrogenation of propane. The as-synthesized catalysts were characterized by using the XRD, BET, NH$_{3}$-TPD, TPR, and XPS methods. The catalytic tests were performed in a fixed bed tubular quartz reactor system between 450 and 550 $^{\circ}$C. It was observed that the conversion of propane increased but hydrocarbon selectivity decreased with increasing temperature over the V$_{2}$O$_{5}$/MgAl$_{2}$O$_{4}$ catalysts. The BET surface area values and surface acidities decreased upon potassium addition for the K-V$_{2}$O$_{5}$/MgAl$_{2}$O$_{4}$ catalysts, which resulted in a drastic drop in the conversion values obtained. The propylene and total …

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Investigation Of Long-Term Water Absorption Behavior Of Carbon Fabric Reinforced Epoxy Composites Containing Hydrophobic Nanosilica, Nurten Eki̇n, Mehmet Gali̇p İçduygu, Ahmet Gültek Jan 2016

Investigation Of Long-Term Water Absorption Behavior Of Carbon Fabric Reinforced Epoxy Composites Containing Hydrophobic Nanosilica, Nurten Eki̇n, Mehmet Gali̇p İçduygu, Ahmet Gültek

Turkish Journal of Chemistry

hydrophobic filler containing epoxy matrix composites was investigated by keeping them in distilled water for 9 months. Aerosil R812 (8 nm) and Aerosil R972 (12 nm) were utilized at 3{\%} and 5{\%} w/w filler to resin ratio and the resin/filler mixture was combined with 12-ply carbon fabric to get 15 $\times $ 15 cm samples. Samples were molded under a hot press and for each sample 50 test samples obtained by cutting them with a water jet. The obtained samples were characterized by TG, FTIR, and SEM. The effect of water absorption was evaluated by measuring percentage water absorption and …

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Polybrominated Methoxy- And Hydroxynaphthalenes, Kiymet Berki̇l Akar, Osman Çakmak, Tuncay Tunç Jan 2016

Polybrominated Methoxy- And Hydroxynaphthalenes, Kiymet Berki̇l Akar, Osman Çakmak, Tuncay Tunç

Turkish Journal of Chemistry

Regio- and stereoselective synthesis are described for convenient preparation of hydroxy- and methoxynaphthalenes starting from naphthalene (\textbf{1}). \textit{cis,cis,trans}-2,3,5,8-Tetrabromo-4-methoxy-1,2,3,4-tetrahydronaphthalen-1-ol (\textbf{6}), \textit{cis,cis,trans}-2,3,5,8-tetrabromo-1,4-dimethoxy-1,2,3,4-tetrahydronaphthalene (\textbf{7}), and \textit{cis,cis,cis}-2,3,5,8-tetrabromo-1,4-dimethoxy-1,2,3,4-tetrahydronaphthalene (\textbf{8}) were obtained with silver-induced substitution of \textit{trans,cis,trans}-1,2,3,4, 5,8-hexabromo-1,2,3,4-tetrahydronaphthalene (\textbf{3}). Base-promoted aromatization of dimethoxides \textbf{7} and \textbf{8} afforded 3,5,8-tribromo-1-methoxynaphthalene (\textbf{9}) and 2,5,8-tribromo-1-methoxynaphthalene (\textbf{10}). The reaction of \textbf{6 }with sodium methoxide formed compounds \textbf{10 }and 3,5,8-tribromonaphthalen-1-ol (\textbf{16}). Bromination of \textbf{9} and\textbf{ 16} with Br$_{2}$ in dichloromethane at room temperature produced 2,3,5,8-tetrabromo-1-methoxynaphthalene (\textbf{14}) and 2,3,4,5,8-pentabromonaphthalen-1-ol (\textbf{18}), respectively, while compound \textbf{10} did not react in the same conditions. Pyridine-induced elimination of hexabromide \textbf{3} afforded 1,4,6\textbf{-}tribromnaphthalene (\textbf{21}) in 99{\%} yield and …

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