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Articles 5071 - 5100 of 10319
Full-Text Articles in Physical Sciences and Mathematics
An Indirect Model For Sintering Thermodynamics, Yüksel Sarikaya, Müşerref Önal
An Indirect Model For Sintering Thermodynamics, Yüksel Sarikaya, Müşerref Önal
Turkish Journal of Chemistry
A model was proposed and used to calculated the changes in enthalpy $(\Delta H^{o})$, entropy $(\Delta S^{o}),$ and Gibbs energy $(\Delta G^{o})$, as well as equilibrium constant $(K)$ relating to the sintering of alumina compacts. Specific nanopore volume $(V)$ of the compacts was assumed as a thermodynamic variable. A hypothetical equilibrium constant $(K_{h})$ and corresponding Gibbs energy $(\Delta G_{h}^{o})$ were calculated depending on the $V$ value measured after each sintering. The thermodynamic relationships with the SI units were respectively evaluated for the initial-stage $(i)$ sintering between 1000 and 1200 $^{\circ}$C and final-stage $(f)$ sintering between 1200 and 1600 $^{\circ}$C in …
Latest Trends, Green Aspects, And Innovations In Liquid-Phase--Based Microextraction Techniques: A Review, Erkan Yilmaz, Mustafa Soylak
Latest Trends, Green Aspects, And Innovations In Liquid-Phase--Based Microextraction Techniques: A Review, Erkan Yilmaz, Mustafa Soylak
Turkish Journal of Chemistry
Liquid-phase microextraction (LPME) methods including single-drop microextraction (SDME), hollow-fiber LPME (HF-LPME), and dispersive liquid-liquid microextraction (DLLME) have in the very short time since their invention grabbed the attention of scientists. Up to now, LPME methods have shown important innovations for the extraction and preconcentration of both inorganic and organic trace analytes from different matrices. These LPME methods offer unique advantages such as high preconcentration factor for target analytes in a single step, low cost, simplicity, excellent preconcentration capability, sample cleanup and integration of steps, and combined use with almost every analytical measurement technique. We describe the milestones and the combined …
Chromium Redox Speciation In Food Samples, Krystyna Pyrzynska
Chromium Redox Speciation In Food Samples, Krystyna Pyrzynska
Turkish Journal of Chemistry
Chromium is an element with important biological characteristics, depending on its different species. Cr(III) is considered as essential; however, the Cr(VI) form is classified as carcinogenic.~For this reason, speciation analysis in food samples is a very important question. The proposed data procedures for chromium redox speciation in the literature can be divided into those with the use of online hyphenated techniques and those where appropriate sample pretreatment is necessary. The strategies for nonchromatographic speciation are mainly based on selective liquid--liquid extraction procedures, coprecipitation, selective separation of chromium species using a solid phase extraction column, or complexation reactions. In this paper, …
Remediation Of Cr(Vi) Via Combined Self-Reduction And Adsorption Bychemically Modified Carbon Sorbents, Mohamed E. Mahmoud, Amr. A. Yakout, Asmaa M. Halbas, Maher M. Osman
Remediation Of Cr(Vi) Via Combined Self-Reduction And Adsorption Bychemically Modified Carbon Sorbents, Mohamed E. Mahmoud, Amr. A. Yakout, Asmaa M. Halbas, Maher M. Osman
Turkish Journal of Chemistry
Hexavalent chromium, Cr(VI), is a highly toxic species, while trivalent chromium, Cr(III), is an essential trace element for humans and other organisms. In the present work, a simple, rapid, and efficient procedure for water treatment of Cr(VI) is described. Active carbon (AC) was chemically treated with HCl and NaOH for the formation of surface modified Acidic-AC and Basic-AC sorbents, respectively. In addition, AC sorbent was treated with HNO$_{3}$ as an oxidizing agent and sodium sulfite as a reducing agent for the formation of Ox-AC and Rd-AC sorbents, respectively. The modified AC sorbents were tested to identify their potential applications in …
Chromate Surface-Imprinted Silica Gel Sorbent For Speciation Of Cr In Surface Waters, Mariya Mitreva, Ivanka Dakova, Tanya Yordanova, Irina Karadjova
Chromate Surface-Imprinted Silica Gel Sorbent For Speciation Of Cr In Surface Waters, Mariya Mitreva, Ivanka Dakova, Tanya Yordanova, Irina Karadjova
Turkish Journal of Chemistry
This study is focused on the synthesis of chromate anion imprinted sorbent supported on silica gel for nonchromatographic Cr speciation in surface waters. The preparation procedure is based on grafting of 3-methyl-1-trimethoxysilylpropylimidazolium, preliminarily coordinated to CrO$_{4}^{2-}$ as a template ion, onto the surface of silica gel. Sorption and desorption characteristics of surface-imprinted sorbent toward Cr(III) and Cr(VI) were examined by batch solid-phase extraction. An excellent separation of Cr(VI), selectively retained on the sorbent, from Cr(III) remained in the solution, was achieved at pH 2-3 for 20 min. A freshly prepared mixture of ascorbic acid and nitric acid was selected as …
A Novel Ion-Imprinted Polymeric Sorbent For Separation And Determination Of Chromium(Iii) Species In Wastewater, Barbara Lesniewska, Iwona Jakubowska, Elzbieta Zambrzycka, Beata Godlewska - Zylkiewicz
A Novel Ion-Imprinted Polymeric Sorbent For Separation And Determination Of Chromium(Iii) Species In Wastewater, Barbara Lesniewska, Iwona Jakubowska, Elzbieta Zambrzycka, Beata Godlewska - Zylkiewicz
Turkish Journal of Chemistry
A new chromium(III) ion-imprinted polymer (IIP) was prepared from a Cr(III)-nicotinate complex (template), acrylamide (functional monomer), and ethylene glycol dimethacrylate (cross-linking agent) using 2,2'-azobisisobutyronitrile as the radical initiator. IIP was characterised and used as a selective sorbent for the solid-phase extraction of Cr(III) ions. The conditions for dynamic separation of Cr(III) on IIP were optimised. Cr(III) ions are selectively retained on the sorbent in a pH range from 9 to 10 and can be eluted with 4 mol L$^{-1}$ acetic acid. Cr(III) ions were determined by flame atomic absorption spectrometry (FAAS) with a detection limit of 0.08 $\mu $g mL$^{-1}$. …
Determination Of Hexavalent Chromium In Aqueous And Alkaline Soil Extracts, Tsvetomil Voyslavov, Stefan Tsakovski, Sonya Ganeva
Determination Of Hexavalent Chromium In Aqueous And Alkaline Soil Extracts, Tsvetomil Voyslavov, Stefan Tsakovski, Sonya Ganeva
Turkish Journal of Chemistry
A fast, simple, and reliable method for determination of hexavalent chromium species in soil aqueous and alkaline extracts has been developed. The procedure is based on the ion-pair extraction of Cr(VI) with methyltrioctylammonium chloride (Aliquat 336) into xylene. The extract is analyzed by flame (FAAS) or electrothermal atomic absorption spectrometry (ETAAS). The method allows the detection of up to 2 mg kg$^{-1}$ Cr(VI) by FAAS and up to 25 $\mu $g kg$^{-1}$ Cr(VI) by ETAAS. The relative standard deviation varied in the range 2%-12% depending on the Cr(VI) levels in the samples. The analysis of certified reference material CRM041-30G Chromium …
Schiff Base Immobilized Silica Gel Framework As An Efficient Sorbent For Preconcentration Of Pb And Zn Ions In Aqueous Media, Murat Koluman, Feyzullah Tokay, Sema Bağdat
Schiff Base Immobilized Silica Gel Framework As An Efficient Sorbent For Preconcentration Of Pb And Zn Ions In Aqueous Media, Murat Koluman, Feyzullah Tokay, Sema Bağdat
Turkish Journal of Chemistry
A novel preconcentration method for Pb and Zn ions using a column packed with Schiff base modified silica gel is described. The method was based on the sorption of analytes on N,N'-bis(4-methoxysalicylidene)-1,3-propanediamine modified silica gel and elution with HNO$_{3}$ prior to flame atomic absorption analysis. The parameters pH, flow rate, sample volume, eluent volume, and concentration were optimized using a central composite design. The detection limits were 10.0 $\mu $g L$^{-1}$ for Pb and 1.1 $\mu $g L$^{-1}$ for Zn. The suggested procedure was validated with Lake Ontario water as a certified reference material and recovery percentages were 101.8% for …
An Application Of Coacervate-Based Extraction For The Separation And Preconcentration Of Cadmium, Lead, And Nickel Ions Prior To Their Determination By Flame Atomic Absorption Spectrometry In Various Water Samples, Anies Awad Satti, İlknur Durukan Temuge, Sema Bektaş, Çi̇ğdem Arpa Şahi̇n
An Application Of Coacervate-Based Extraction For The Separation And Preconcentration Of Cadmium, Lead, And Nickel Ions Prior To Their Determination By Flame Atomic Absorption Spectrometry In Various Water Samples, Anies Awad Satti, İlknur Durukan Temuge, Sema Bektaş, Çi̇ğdem Arpa Şahi̇n
Turkish Journal of Chemistry
Cloud point extraction (CPE), which is the most popular coacervate-based extraction method, was utilized for the separation and preconcentration of trace amounts of cadmium, lead, and nickel. Quinalizarin was used as complexing agent and Triton X-114 was used as surfactant. After extraction, analyte ions were determined by flame atomic absorption spectrometry. The detection limits (3$s)$ of 1.8 $\mu $g L$^{-1}$ for Cd(II), 3.2 $\mu $g L$^{-1}$ for Pb(II), and 2.8 $\mu $g L$^{-1}$ for Ni(II) were obtained using 50 mL of solutions. The relative standard deviation was calculated as 4.3% for 10 $\mu $g L$^{-1}$ Cd(II), 4.9% for 50 $\mu …
A Simple And Efficient Approach For Preconcentration Of Some Heavy Metals In Cosmetic Products Before Their Determinations By Flame Atomic Absorption Spectrometry, Nai̇l Altunay, Ramazan Gürkan
A Simple And Efficient Approach For Preconcentration Of Some Heavy Metals In Cosmetic Products Before Their Determinations By Flame Atomic Absorption Spectrometry, Nai̇l Altunay, Ramazan Gürkan
Turkish Journal of Chemistry
In the current study, a simple and efficient analytical method for preconcentration and determination of Cd(II), Pb(II), and Sn(II) in some cosmetic samples, using ultrasonic assisted-cloud point extraction and flame atomic absorption spectrometry, was developed. The method is based on the ternary complex formations of Sn(II), Pb(II), and Cd(II), which are available in the form of neutral and/or anionic hydroxo complexes (Sn(OH)$_{3}^{-}$, Pb(OH)$_{3}^{-}$, Cd(OH)$_{2}$, and/or Cd(OH)$_{3}^{-})$, with Victoria Pure Blue BO (VPB$^{+})$ in the presence of cetylpyridinium chloride at pH 8.5, and then extraction of the formed ternary complexes into the micellar phase of polyoxyethylene sorbitan monostearate (Tween 60). Using …
Solidified Floating Organic Drop Microextraction For Speciation Of Se (Iv) And Se (Vi) In Water Samples Prior To Electrothermal Atomic Absorption Spectrometric Detection, Demi̇rhan Çitak, Mustafa Tüzen
Solidified Floating Organic Drop Microextraction For Speciation Of Se (Iv) And Se (Vi) In Water Samples Prior To Electrothermal Atomic Absorption Spectrometric Detection, Demi̇rhan Çitak, Mustafa Tüzen
Turkish Journal of Chemistry
A simple and fast solidified floating organic drop microextraction (SFODME) method is suggested for the speciation of Se (IV) and Se (VI) in water samples prior to electrothermal atomic absorption spectrometric (ETAAS) detection. For that purpose, 1-phenylthiosemicarbazide (PTC) was used as chelating agent and undecanol was used as extraction solvent. The pH of solution, extraction solvent volume, amount of ligand, effect of time for complex formation, and effect of possible foreign ions were also evaluated for quantitative and effective extraction of analyte. Under optimized parameters, detection limit (0.19 $\mu $g L$^{-1})$, limit of quantification (0.60 $\mu $g L$^{-1})$, relative standard …
Ionic Liquid Based Microextraction Combined With Derivatization For Efficient Enrichment/Determination Of Asulam And Sulfide, Habibollah Eskandari, Mahnaz Shahbazi-Raz
Ionic Liquid Based Microextraction Combined With Derivatization For Efficient Enrichment/Determination Of Asulam And Sulfide, Habibollah Eskandari, Mahnaz Shahbazi-Raz
Turkish Journal of Chemistry
This study reports 2 new simple derivatization-based dispersive liquid-liquid microextraction (DLLME) methods for spectrophotometric ultratrace determination of asulam and sulfide. 1-Naphthol (in the presence of nitrite) and N,N-diethyl-p-phenylenediamine (in the presence of Fe(III)) were used to derivatize asulam and sulfide, respectively. In the enrichment methods, the formed derivatives were preconcentrated into microdroplets of the in situ formed water insoluble ionic liquid (IL), 1-hexyl-3-methylimidazolium hexafluorophosphate. Monitoring was performed at 526 nm for asulam and at 664 nm for sulfide, after dissolution of the IL-rich phases into the basic ethanolic solution and ethanol for asulam and sulfide, respectively. Beer's law was obeyed …
Separation And Preconcentration Of Pb(Ii) And Cu(Ii) Ions Via Carrier Element-Free Coprecipitation Using An Acetohydrazide Derivative, Süreyya Oğuz Tümay, Murat Yazar, Duygu Özdeş, Hakan Bektaş, Celal Duran
Separation And Preconcentration Of Pb(Ii) And Cu(Ii) Ions Via Carrier Element-Free Coprecipitation Using An Acetohydrazide Derivative, Süreyya Oğuz Tümay, Murat Yazar, Duygu Özdeş, Hakan Bektaş, Celal Duran
Turkish Journal of Chemistry
A new method based on the combination of carrier element-free coprecipitation and flame atomic absorption spectrometric determination has been investigated for simultaneous separation and preconcentration of Pb(II) and Cu(II) ions in some environmental solid and liquid samples. The 2-{3-(4-methylbenzyl)-4-[2-(1H-indol-3-yl)ethyl]-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl} -N'-(phenylmethylene) acetohydrazide (MITA) was utilized as an organic coprecipitating agent without using a carrier element for coprecipitation of the analyte ions. The effects of experimental conditions including aqueous solution pH, MITA quantity, sample volume, standing time, and centrifugation rate and time were investigated in detail and optimized. The influences of some foreign ions were also evaluated on the quantitative recoveries of …
Development Of A Method For The Determination Of Cadmium Levels In Seawater By Flame Atomic Absorption Spectrometry Using An Online Cloud-Point Extraction System, Rafael Vasconcelos Oliveira, Uelber Silva Vieira, Mardson Vasconcelos Maciel, Thais Souza Neri, Graziele Santos Sales, Rebeca Moraes Menezes, Valfredo Azevedo Lemos
Development Of A Method For The Determination Of Cadmium Levels In Seawater By Flame Atomic Absorption Spectrometry Using An Online Cloud-Point Extraction System, Rafael Vasconcelos Oliveira, Uelber Silva Vieira, Mardson Vasconcelos Maciel, Thais Souza Neri, Graziele Santos Sales, Rebeca Moraes Menezes, Valfredo Azevedo Lemos
Turkish Journal of Chemistry
A new system was developed for the preconcentration and determination of cadmium levels in water following online cloud-point extraction and analysis by flame atomic absorption spectrometry. The method uses cloud-point extraction of the complex formed between Cd(II) ions and the reagent 2-(5-bromo-2'-thiazolylazo)-$p$-cresol (Br-TAC) using Triton X-114 as a surfactant. The main steps of the procedure, extraction, filtration, and detection were conducted online. Parameters that influence the experimental conditions of online preconcentration systems were examined, including pH, concentration of reagent and surfactant, and flow of sample and eluent. The limit of detection of the method is 0.2 $\mu $g L$^{-1}$. The …
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
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 …
Effects Of Variable Viscosity And Thermal Conductivity On Magnetohydrodynamic Free Convection Flow Of A Micropolar Fluid Past A Stretching Plate Through Porous Medium With Radiation, Heat Generation, And Joule Dissipation, Gopal Chandra Hazarika, Bandita Phukan
Effects Of Variable Viscosity And Thermal Conductivity On Magnetohydrodynamic Free Convection Flow Of A Micropolar Fluid Past A Stretching Plate Through Porous Medium With Radiation, Heat Generation, And Joule Dissipation, Gopal Chandra Hazarika, Bandita Phukan
Turkish Journal of Physics
The effects of temperature-dependent viscosity and thermal conductivity on free convection magnetohydrodynamic flow of an optically thin gray, viscous, and incompressible micropolar fluid and heat transfer past a stretching plate through porous medium in the presence of radiation, heat generation, and Joule dissipation were studied. The fluid viscosity and thermal conductivity were assumed to vary as inverse linear functions of temperature. Using similarity transformation, the governing partial differential equations of motion were reduced to ordinary ones, which were solved numerically for prescribed boundary conditions using the shooting method. Numerical results for the velocity, angular velocity, and temperature profiles are shown …
Amplitude Modulation Of Ion-Acoustic Waves In Magnetized Electron-Positron-Ion Plasma With Q-Nonextensive Electrons And Positrons, Basudev Ghosh, Sreyasi Banerjee
Amplitude Modulation Of Ion-Acoustic Waves In Magnetized Electron-Positron-Ion Plasma With Q-Nonextensive Electrons And Positrons, Basudev Ghosh, Sreyasi Banerjee
Turkish Journal of Physics
Using a standard reductive perturbation technique, a nonlinear Schrödinger equation has been derived that describes the nonlinear evolution of ion-acoustic waves in magnetized electron-positron-ion plasma with electrons and positrons following q-nonextensive distribution. It is shown that excitation of both bright and dark envelope solitary structures is possible in the model plasma under consideration. The conditions for the excitation and structure of these envelope solitary waves are shown to depend sensitively on the strength of the external magnetic field, obliqueness of wave propagation relative to the external magnetic field, and other plasma parameters such as the q-nonextensivity of plasma species, positron …
Effects Of Variable Viscosity And Thermal Conductivity On Magnetohydrodynamic Free Convection Dusty Fluid Along A Vertical Porous Plate With Heat Generation, Gopal Chandra Hazarika, Jadav Konch
Effects Of Variable Viscosity And Thermal Conductivity On Magnetohydrodynamic Free Convection Dusty Fluid Along A Vertical Porous Plate With Heat Generation, Gopal Chandra Hazarika, Jadav Konch
Turkish Journal of Physics
The present study investigated the effects of variable viscosity and thermal conductivity on a two-dimensional steady laminar magnetohydrodynamic (MHD) free convective boundary layer flow of a dusty fluid over a vertical porous flat plate with viscous dissipation, Joule heating, and heat generation/absorption. Governing partial differential equations of motion were reduced to a system of ordinary differential equations using similarity transformations. The resulting boundary value problem was then solved numerically using the shooting technique. Velocity, temperature, and species concentration profiles of fluid and solid particles were obtained for different flow governing parameters. The results are presented in graphs. We found that …
Pp-Waves In Modified Gravity, Ahmet Baykal
Pp-Waves In Modified Gravity, Ahmet Baykal
Turkish Journal of Physics
The family of metrics corresponding to the plane-fronted gravitational waves with parallel propagation, commonly referred to as the family of pp-wave metrics, is studied in the context of various modified gravitational models in a self-contained and coherent manner by using a variant of the null coframe formulation of Newman and Penrose and the exterior algebra of differential forms on pseudo-Riemannian manifolds.
Structure And Stability Of Primordial Stars, Aysel İbrahi̇m Karafi̇stan
Structure And Stability Of Primordial Stars, Aysel İbrahi̇m Karafi̇stan
Turkish Journal of Physics
For decades large-scale cosmic structures have been modeled as the gravitational amplification of small-density perturbations of the cosmological recombination epoch of the Big Bang. In astrophysics, cosmological nucleosynthesis is considered responsible for the production of the pristine gas, which should be found in the first-generation stars in the form of hydrogen and helium as the main constituents. In the later type of second-generation stars, hydrogen is converted into helium by the CN-cycle reactions, in which heavier elements are produced. These elements are believed to enrich the intergalactic medium by possible star bursts at the last stages of evolution. Stability criteria …
Upper Cenomanian-Lower Campanian Derdere And Karababa Formations In The Çemberlitaş Oil Field, Southeastern Turkey: Their Microfacies Analyses, Depositional Environments, And Sequence Stratigraphy, Oğuz Mülayi̇m, Ernest Mancini, İbrahi̇m Çemen, İsmai̇l Ömer Yilmaz
Upper Cenomanian-Lower Campanian Derdere And Karababa Formations In The Çemberlitaş Oil Field, Southeastern Turkey: Their Microfacies Analyses, Depositional Environments, And Sequence Stratigraphy, Oğuz Mülayi̇m, Ernest Mancini, İbrahi̇m Çemen, İsmai̇l Ömer Yilmaz
Turkish Journal of Earth Sciences
The frontal belt of the southeastern Anatolia fold-thrust belt in Turkey contains several small to mid-size oilfields, producing from carbonate reservoirs of the Cretaceous Mardin group. Many of these fields are found along narrow, asymmetrical anticlinal structures, associated with the formation of the fold-thrust belt. The Çemberlitaş oil field in Adıyaman, southeastern Turkey, is one of the most important oilfields in the region. It produces from the Upper Cretaceous Derdere and Karababa formations of the Mardin group. We have conducted a detailed study of the microfacies, depositional environments, and sequence stratigraphy of the Karababa (Coniacian-lower Campanian) and Derdere (mid-Cenomanian-Turonian) formations …
Late Quaternary Paleoceanographic Evolution Of The Aegean Sea: Planktonic Foraminifera And Stable Isotopes, Ekrem Bursi̇n İşler, Ali̇ Engi̇n Aksu, Richard Nicholas Hiscott
Late Quaternary Paleoceanographic Evolution Of The Aegean Sea: Planktonic Foraminifera And Stable Isotopes, Ekrem Bursi̇n İşler, Ali̇ Engi̇n Aksu, Richard Nicholas Hiscott
Turkish Journal of Earth Sciences
Aspects of the paleoclimatic and paleoceanographic evolution of the Aegean Sea since ~130 ka are revealed by quantitative variations in planktonic faunal assemblages, the Δ18O and Δ13C isotopic composition of benthic and planktonic foraminifera, and Mg/Ca ratios in planktonic foraminifera extracted from five 6-10-m-long piston cores. Independent sea surface temperature (SST) estimates obtained using planktonic foraminiferal transfer functions and the Mg/Ca ratios show excellent agreement, with r2 correlation coefficients of 0.92-0.95. Planktonic foraminiferal assemblages are similar, through time, across several deep basins, suggesting that major changes must have occurred in near synchroneity across the Aegean Sea. The data suggest that …
Quartz-Mica Schist And Gneiss Hosted Clay Deposits Within The Yenipazar(Yozgat, Central Anatolia) Volcanogenic Massive Sulfide Ore, Şih Ali̇ Sayin
Quartz-Mica Schist And Gneiss Hosted Clay Deposits Within The Yenipazar(Yozgat, Central Anatolia) Volcanogenic Massive Sulfide Ore, Şih Ali̇ Sayin
Turkish Journal of Earth Sciences
The Yenipazar deposit of volcanogenic sulfide occurrence, situated approximately 9 km SW of Yenipazar, is hosted in quartz-muscovite schists and gneiss. Following the Late Cretaceous, the quartz-mica schists and gneiss have been altered to clay minerals, resulting in important kaolin deposits. The clay deposits consist mainly of halloysite, kaolinite, smectite, illite, muscovite, chlorite, and α-quartz. Biotite, alunite, jarosite, pyrite, hematite, calcite, low cristobalite, and feldspar are present in minor amounts. In places, some mixed-layer clays, such as kaolinite/smectite and smectite/illite, are also observed within the clay deposits. Barite is present in a few clay samples. α-Quartz is the dominant silica …
Geochemistry Of Proterozoic Clastic Rocks Of The Kerur Formation Of Kaladgi-Badami Basin, North Karnataka, South India: Implications For Paleoweathering And Provenance, Ariputhiran Ramachandran, Jayagopal Madhavaraju, Sooriamuthu Ramasamy, Yong Il Lee, Sesha Rao, David Lalhmingliana Chawngthu, Kasilingam Velmurugan
Geochemistry Of Proterozoic Clastic Rocks Of The Kerur Formation Of Kaladgi-Badami Basin, North Karnataka, South India: Implications For Paleoweathering And Provenance, Ariputhiran Ramachandran, Jayagopal Madhavaraju, Sooriamuthu Ramasamy, Yong Il Lee, Sesha Rao, David Lalhmingliana Chawngthu, Kasilingam Velmurugan
Turkish Journal of Earth Sciences
Major, trace, and rare earth element (REE) studies have been conducted on the Proterozoic clastic rocks of the Kerur Formation of the Kaladgi-Badami Basin, South India, to determine their paleoweathering conditions and provenance characteristics. Geochemically, these sedimentary rocks are classified as quartz arenite, arkose, litharenite, and sublitharenite. The chemical index of alteration values and the A-CN-K diagram suggest that the clastics rocks in this study underwent moderate to intensive weathering. Chondrite-normalized REE patterns with light REE enrichment, flat heavy REE, and a negative Eu anomaly also attribute felsic source-rock to sedimentary rocks of the Kerur Formation. In addition, Eu/Eu* (~0.77), …
Notes On Beyrichiacean Ostracodes From The Early Devonian Of Nw Turkey Andtheir Palaeobiogeographical Relations, Ati̇ke Nazi̇k, Helga Groos-Uffenorde
Notes On Beyrichiacean Ostracodes From The Early Devonian Of Nw Turkey Andtheir Palaeobiogeographical Relations, Ati̇ke Nazi̇k, Helga Groos-Uffenorde
Turkish Journal of Earth Sciences
Recently found materials of large beyrichiacean ostracodes from the Early Devonian of the Darlık, Korucuköy, and Kabalakdere sections in NW Anatolia stimulated the restudy of ostracode collections from the İstanbul area, including the Toula collection (GBA Vienna) and Endriss collection (previously in GPI Marburg and currently in SMF Frankfurt), and their biostratigraphical and palaeogeographical significance. The species Gibba kayseri, Gibba schmidti, Zygobeyrichia roemeri, Zygobeyrichia subcylindrica, and Zygobeyrichia onusta are documented and beyrichiid gen. et sp. indet. is described. There are great similarities with ostracode faunas from Early Devonian shallow-water sediments of Europe and North Africa (in Germany from the Rhenish …
Comparison Between Natural Radioactivity Levels Andgeochemistry Of Some Granitoids In Western Turkey, Si̇bel Tatar Erkül, Süleyman Fati̇h Özmen, Fuat Erkül, İsmai̇l Boztosun
Comparison Between Natural Radioactivity Levels Andgeochemistry Of Some Granitoids In Western Turkey, Si̇bel Tatar Erkül, Süleyman Fati̇h Özmen, Fuat Erkül, İsmai̇l Boztosun
Turkish Journal of Earth Sciences
Granitoids commonly include K-feldspar, biotite and zircon, apatite, titanite, allanite, and xenotime crystals, which are known to contain common radioactive elements. Radioactive isotopes of 40K, 238U, and 232Th can be harmful to human health with increasing dosage and their quantification should be well defined to assess the suitability of wall-rock granitoids for indoor and outdoor purposes. In this study, it is aimed to correlate the possible relationship between concentrations of natural radionuclides and SiO2, Na2O, K2O, and CaO together with elements U, Th, Zr, Y, Ba, Rb, and Sr to provide a basic approach to the compatibility of geochemical data …
Sulfur Isotope Study Of Vent Chimneys From Upper Cretaceous Volcanogenic Massive Sulfide Deposits Of The Eastern Pontide Metallogenic Belt, Ne Turkey, Mustafa Kemal Revan, Valeri̇y V. Maslennikov, Yurdal Genç, Okan Deli̇baş, Svetlana P. Maslennikova, Sergey A. Sadykov
Sulfur Isotope Study Of Vent Chimneys From Upper Cretaceous Volcanogenic Massive Sulfide Deposits Of The Eastern Pontide Metallogenic Belt, Ne Turkey, Mustafa Kemal Revan, Valeri̇y V. Maslennikov, Yurdal Genç, Okan Deli̇baş, Svetlana P. Maslennikova, Sergey A. Sadykov
Turkish Journal of Earth Sciences
We obtained sulfur isotope analysis results of sulfide samples from hydrothermal vent chimneys of the eastern Pontide volcanogenic massive sulfide (VMS) deposits. The total range of δ34S values for vent chimneys in the eastern Pontide VMS deposits is -2.7 to 6.5 per mil. Sulfide Δ34S values show narrow variation in the Lahanos, Killik, and Kutlular deposits, but wider variation in the Kızılkaya and Çayeli deposits. The δ34S values of sulfides in Çayeli chimney samples gave a slightly higher range than the other Pontide chimney samples. In some samples, a rough isotopic zonation pattern was observed throughout chimney zones. Variations in …
Comparative Study On Geochemical Characterization Of The Carboniferousaluminous Argillites From The Huainan Coal Basin, China, Bingyu Chen, Guijian Liu, Dun Wu, Ruoyu Sun
Comparative Study On Geochemical Characterization Of The Carboniferousaluminous Argillites From The Huainan Coal Basin, China, Bingyu Chen, Guijian Liu, Dun Wu, Ruoyu Sun
Turkish Journal of Earth Sciences
Aluminous argillites were widely deposited in the Taiyuan Formation at the Huainan Coalfield at the southeast margin of the North China Plate. However, knowledge about their formation conditions and geochemical characterizations is not presently known. We recovered underground aluminous argillites at depths of 485-610 m from a borehole in the Zhangji Coal Mine and characterized their geochemical parameters, including major and trace elements, by X-ray fluorescence, inductively coupled plasma optical emission spectrometry, and inductively coupled plasma mass spectrometry. The provenance, climatic conditions during the weathering process of parent rocks, weathering extent, and depositional environments of Huainan aluminous argillites were investigated. …
Assimilation And Fractional Crystallization Of Foid-Bearing Alkaline Rocks:Buzlukdağ Intrusives, Central Anatolia, Turkey, Kiymet Deni̇z, Yusuf Kağan Kadioğlu
Assimilation And Fractional Crystallization Of Foid-Bearing Alkaline Rocks:Buzlukdağ Intrusives, Central Anatolia, Turkey, Kiymet Deni̇z, Yusuf Kağan Kadioğlu
Turkish Journal of Earth Sciences
Felsic intrusive rocks within the Central Anatolian Crystalline Complex provide a window into the geodynamic processes in operation during the final closure of the Neotethys Ocean. Previous studies were largely restricted to the calc-alkaline granitoids, and the structural and petrogenetic relations of syenitoids are poorly studied. The Buzlukdağ Intrusive Complex is a silica-undersaturated alkaline syenite that is differentiated into three concentric subgroups according to texture and grain size. Mineral compositions do not vary between the subgroups but differentiation has resulted in different mineral proportions. Mafic microgranular enclaves are present throughout the suite, indicating mingling and mixing between the coeval felsic …
Geochemistry, Zircon U-Pb Age, And Tectonic Constraints On The Bazman Granitoid Complex, Southeast Iran, Mohammad Reza Ghodsi, Mohammad Boomeri, Sasan Bagheri, Daizo Ishiyama, Fernando Corfu
Geochemistry, Zircon U-Pb Age, And Tectonic Constraints On The Bazman Granitoid Complex, Southeast Iran, Mohammad Reza Ghodsi, Mohammad Boomeri, Sasan Bagheri, Daizo Ishiyama, Fernando Corfu
Turkish Journal of Earth Sciences
The Bazman granitoid complex (BGC), including a large zoned pluton, intrudes into the upper Paleozoic sedimentary cover of the Lut block. It crops out on the southern slope of the Bazman volcano in Baluchestan Province of Iran. The intrusive rocks range from gabbro to various metaluminous to weakly peraluminous granites, and they are classified as I-type magmatic series. They display geochemical characteristics of typical volcanic arc magmatism at continental margins. Major- and trace-element variation diagrams show that fractional crystallization was the major process and crustal contamination, a subordinate process during the evolution of the BGC. The decrease in CaO, MgO, …