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Full-Text Articles in Physical Sciences and Mathematics

Pseudoscalar Higgs Boson Pair Production At A Photon-Photon Collision In Thetwo Higgs Doublet Model, Mehmet Demi̇rci̇ Jan 2019

Pseudoscalar Higgs Boson Pair Production At A Photon-Photon Collision In Thetwo Higgs Doublet Model, Mehmet Demi̇rci̇

Turkish Journal of Physics

In this study, the direct pair production of the pseudoscalar Higgs boson at a γγ collision is analyzed in the context of the two Higgs doublet model (THDM), taking into account the complete one-loop contributions. In order to illustrate the effect of the new physics, four benchmark point scenarios, which are consistent with theoretical and current experimental constraints, are chosen in the type-I THDM with an exact alignment limit. The effect of individual contributions from each type of one-loop diagram on the total cross-section is examined in detail. The dependence of the cross-section on the center-of-mass energy is also presented …


First Photometric Investigation Of Some Asas Binary Systems, Burak Ulaş Jan 2019

First Photometric Investigation Of Some Asas Binary Systems, Burak Ulaş

Turkish Journal of Physics

We present the first light curve solutions of the four binary systems observed and catalogued by the All Sky Automated Survey (ASAS) program. The light curves are analyzed by using PHOEBE software, which is based on the Wilson?Devinney method. The light curve parameters are derived and the estimated physical parameters are calculated from the result of the analyses. We compare our targets to well-known binaries of similar type on the Hertzsprung-Russell diagram and mass-radius plane. The evolutionary states of the components are also discussed.


The Behaviour Of The Diamagnetic Current Modified Mri In Different Rotationprofiles, Suzan Doğan Jan 2019

The Behaviour Of The Diamagnetic Current Modified Mri In Different Rotationprofiles, Suzan Doğan

Turkish Journal of Physics

Magnetohydrodynamic turbulence driven by magnetorotational instability (MRI) has been widely accepted as an efficient mechanism for transporting angular momentum radially outward in the discs. Previously, we have shown the triggering effect of the magnetization currents and the gradients produced by these currents on MRI for Keplerian discs. In this work, we examine the properties of the diamagnetic current modified MRI for the discs where the epicyclic frequencies deviate from Keplerian behaviour. We show that the diamagnetic effect modifies the instability both for an increasing and for a decreasing angular momentum with radius. The novel unstable region produced by magnetization effects …


Second-Order Gauge-Invariant Perturbation Theory And Conserved Charges Incosmological Einstein Gravity, Emel Altaş Ki̇raci Jan 2019

Second-Order Gauge-Invariant Perturbation Theory And Conserved Charges Incosmological Einstein Gravity, Emel Altaş Ki̇raci

Turkish Journal of Physics

Recently a new approach in constructing the conserved charges in cosmological Einstein gravity was given. In this new formulation, instead of using the explicit form of the field equations, a covariantly conserved rank-four tensor was used. In the resulting charge expression, instead of the first derivative of the metric perturbation, the linearized Riemann tensor appears along with the derivative of the background Killing vector fields. Here we give a detailed analysis of the first-order and the second-order perturbation theory in a gauge-invariant form in cosmological Einstein gravity. The linearized Einstein tensor is gauge-invariant at the first order but it is …


Ab Initio Atomistic Thermodynamics Modeling Of Adsorption Of Oxygen On Goldand Gold-Silver Surfaces, Mehmet Gökhan Şensoy Jan 2019

Ab Initio Atomistic Thermodynamics Modeling Of Adsorption Of Oxygen On Goldand Gold-Silver Surfaces, Mehmet Gökhan Şensoy

Turkish Journal of Physics

A theoretical study of oxygen adsorption on gold and gold-silver surfaces by means of density functional theory (DFT) calculations with an atomistic thermodynamic model is performed. The (111) and (211) facets of gold and gold-silver alloy surfaces are considered, and their stabilization is discussed upon adsorption of oxygen depending on O and Ag coverage. The details of how the DFT-based atomistic thermodynamic model can apply to the transition metal surface are also presented in this work.


Two-Dimensional Ti2c Monolayer (Mxene): Surface Functionalization, Inducedmetal, Semiconductor Transition, Berna Akgenc Jan 2019

Two-Dimensional Ti2c Monolayer (Mxene): Surface Functionalization, Inducedmetal, Semiconductor Transition, Berna Akgenc

Turkish Journal of Physics

Recently, two-dimensional (2D) transition metal carbides and nitrides known as MXenes, have gained a lot of attention because of their tunable electronic and magnetic properties depending on surface functionalization. In the present work, the structural, electronic, and magnetic properties of both T and H phases of bare Ti2C and fully surface terminated Ti2 CT2 (T = -F, = O, -OH) are calculated using a set of first principles calculations. The ground state structures of Ti2 CT2 are computed in two and four different configurations for both H and T phases, respectively. We demonstrate that while H phase of Ti2C exhibits …


A Hard X-Ray Self-Amplified Spontaneous Emission Free-Electron Laser Optimization Using Evolutionary Algorithms For Dedicated User Applications, Di̇dem Ketenoğlu, Gazi̇ Erkan Bostanci, Ayhan Aydin, Bora Ketenoğlu Jan 2019

A Hard X-Ray Self-Amplified Spontaneous Emission Free-Electron Laser Optimization Using Evolutionary Algorithms For Dedicated User Applications, Di̇dem Ketenoğlu, Gazi̇ Erkan Bostanci, Ayhan Aydin, Bora Ketenoğlu

Turkish Journal of Physics

Accelerator-based fourth-generation light sources are utilized in a wide range of interdisciplinary applications such as nanotechnology, materials science, biosciences, and medicine. A hard X-ray free-electron laser (FEL), as a state-of-the-art light source, was optimized using evolutionary algorithms for dedicated user applications such as X-ray Raman scattering (XRS), resonant inelastic X-ray scattering (RIXS), and X-ray emission spectroscopies (XES). Optimal parameter sets were obtained for an in-vacuum planar undulator driven by an 8 GeV electron beam. Performance parameters of self-amplified spontaneous emission (SASE) operation (i.e. optimized SASE performance parameters through evolutionary algorithms) were found to be consistent with operating X-ray FEL facilities …


Tuning The Electrical And Morphological Characteristics Of Pedot:Pss Films Through Mixed Cosolvent Addition And Performance Of Their Polymer Solar Cells, Çi̇sem Kirbiyik Jan 2019

Tuning The Electrical And Morphological Characteristics Of Pedot:Pss Films Through Mixed Cosolvent Addition And Performance Of Their Polymer Solar Cells, Çi̇sem Kirbiyik

Turkish Journal of Physics

This work aimed to reveal the influence of premixed cosolvent addition to low conductive PEDOT:PSS solution and how the optimized thin film conductivity develops. PEDOT:PSS thin films were obtained by addition of EG and MeOH cosolvent mixture (8, 10, and 15 v/v.%) and the morphological, electrical, optical, and bandgap properties of the films obtained were characterized by different techniques. The addition of mixed cosolvent can effectively control the grain size distribution and thus the conductivity. The optical characterization results revealed that the bandgap decreased with increasing volume of mixed cosolvent. The conductivity characteristics showed that the addition of 10% v/v.% …


Relativistic Dynamics Of A Scalar Boson Confined By Woods-Saxon Potential In Anucleus, Nuray Candemi̇r Jan 2019

Relativistic Dynamics Of A Scalar Boson Confined By Woods-Saxon Potential In Anucleus, Nuray Candemi̇r

Turkish Journal of Physics

We undertook a theoretical study of a scalar boson confined by Woods-Saxon potential in a nucleus via the Duffin-Kemmer-Petiau equation. We analytically obtained the eigenvectors and energy levels through the hypergeometric functions. Single-particle energy levels of a boson in the ${}^{208} {Pb}$ nucleus were calculated numerically.


Interpretation Of Sea Level Change Using Paleobiodiversity Analysis: The Darende Formation Of The Eocene (Malatya Basin, East Turkey), Si̇bel Kayğili, Ercan Aksoy Jan 2019

Interpretation Of Sea Level Change Using Paleobiodiversity Analysis: The Darende Formation Of The Eocene (Malatya Basin, East Turkey), Si̇bel Kayğili, Ercan Aksoy

Turkish Journal of Earth Sciences

This study was conducted in the Paleogene-Neogene Malatya Basin situated in Eastern Anatolia with particular focus on the analyses of the paleobiodiversity of the larger benthic foraminifera assemblage found in the late Lutetian-Bartonian Yenice and Asartepe members of the Darende Formation. Frequency, dominance, similarity analyses, population size, and diversity indices of the genera/species were obtained for the first time from the analyses of the paleobiodiversity data interpretation obtained by using the larger benthic foraminifera of the Yenice and Asartepe members. According to frequency analysis values, rarely, seldom, generally, frequently, and commonly observed genera and species were determined. The frequency analysis …


Electron Energy Loss Spectroscopy Simulation By A Frequency Domain Surface Integral Equation Solver, İsmai̇l Enes Uysal Jan 2019

Electron Energy Loss Spectroscopy Simulation By A Frequency Domain Surface Integral Equation Solver, İsmai̇l Enes Uysal

Turkish Journal of Electrical Engineering and Computer Sciences

Plasmonic nanoparticles have been mostly studied using conventional light sources. Recently, electron energy loss spectroscopy (EELS) has started to be used to analyze plasmonic nanoparticles where incident electromagnetic fields are created by swift electrons. To accurately simulate EELS experiments, several numerical methods have been adapted. In this paper, a frequency domain surface integral equation (FDSIE) solver is modified to simulate EELS for plasmonic nanoparticles of gold and silver. Accuracy and versatility of the proposed FDSIE solver are shown by several numerical examples and compared to existing numerical, analytical, and experimental results.


A Memory-Efficient Canonical Data Structure For Decimal Floating Point Arithmetic Systems Modeling And Verification, Mohammad Saeed Jahangiry, Saeed Safari Jan 2019

A Memory-Efficient Canonical Data Structure For Decimal Floating Point Arithmetic Systems Modeling And Verification, Mohammad Saeed Jahangiry, Saeed Safari

Turkish Journal of Electrical Engineering and Computer Sciences

Decimal floating point (DFP) number representation was proposed in IEEE-754-2008 in order to overcome binary floating point inaccuracy. Neglecting binary floating point verification has resulted in significant validity and economic losses. Formal verification can be a solution to similar DFP design problems. Verification techniques aiming at DFP are limited to functional methods whereas formal approaches have been neglected and traditional decision diagrams cannot model DFP representation complexity. In this paper, we propose an efficient canonical data structure that can model DFP properties. Our novel data structure models coefficient, exponent, sign, and bias of a DFP number. We will prove mathematically …


Verifiable Dynamic Searchable Encryption, Mohammad Etemad, Alpteki̇n Küpcü Jan 2019

Verifiable Dynamic Searchable Encryption, Mohammad Etemad, Alpteki̇n Küpcü

Turkish Journal of Electrical Engineering and Computer Sciences

Using regular encryption schemes to protect the privacy of the outsourced data implies that the client should sacrifice functionality for security. Searchable symmetric encryption (SSE) schemes encrypt the data in a way that the client can later search and selectively retrieve the required data. Many SSE schemes have been proposed, starting with static constructions, and then dynamic and adaptively secure constructions but usually in the honest-but-curious model. We propose a verifiable dynamic SSE scheme that is adaptively secure against malicious adversaries. Our scheme supports file modification, which is essential for efficiently working with large files, in addition to the ability …


Modified Self-Adaptive Local Search Algorithm For A Biobjective Permutation Flowshop Scheduling Problem, Çi̇ğdem Alabaş Uslu, Berna Dengi̇z, Canan Ağlan, İhsan Sabuncuoğlu Jan 2019

Modified Self-Adaptive Local Search Algorithm For A Biobjective Permutation Flowshop Scheduling Problem, Çi̇ğdem Alabaş Uslu, Berna Dengi̇z, Canan Ağlan, İhsan Sabuncuoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Interest in multiobjective permutation flow shop scheduling (PFSS) has increased in the last decade to ensure effective resource utilization. This study presents a modified self-adaptive local search (MSALS) algorithm for the biobjective permutation flow shop scheduling problem where both makespan and total flow time objectives are minimized. Compared to existing sophisticated heuristic algorithms, MSALS is quite simple to apply to different biobjective PFSS instances without requiring effort or time for parameter tuning. Computational experiments showed that MSALS is either superior to current heuristics for Pareto sets or is incomparable due to other performance indicators of multiobjective problems.


Optimal Dg Allocation For Enhancing Voltage Stability And Minimizing Power Loss Using Hybrid Gray Wolf Optimizer, Salah Kamel, Ayman Awad, Hussein Abdel-Mawgoud, Francisco Jurado Jan 2019

Optimal Dg Allocation For Enhancing Voltage Stability And Minimizing Power Loss Using Hybrid Gray Wolf Optimizer, Salah Kamel, Ayman Awad, Hussein Abdel-Mawgoud, Francisco Jurado

Turkish Journal of Electrical Engineering and Computer Sciences

High penetration of photovoltaic and wind turbine-based distributed generators (DGs) can help reduce carbon emissions which is an important goal for the whole world. DG can be used to improve the voltage stability, present generation reserve/emergency, and consequently, the system power quality can be improved. However, it is very important to select the right size and location of a DG so that the power system can increase the gained benefits of such an installation to the maximum. In this paper, a hybrid optimization technique is proposed to determine the optimal allocation of DG in the standard IEEE 33-bus radial distribution …


Unsupervised Deep Feature Embeddings For Speaker Diarization, Rehan Ahmad, Syed Zubair Jan 2019

Unsupervised Deep Feature Embeddings For Speaker Diarization, Rehan Ahmad, Syed Zubair

Turkish Journal of Electrical Engineering and Computer Sciences

Speaker diarization aims to determine ?who spoke when?? from multispeaker recording environments. In this paper, we propose to learn a set of high-level feature representations, referred to as feature embeddings, from an unsupervised deep architecture for speaker diarization. These sets of embeddings are learned through a deep autoencoder model when trained on mel-frequency cepstral coefficients (MFCCs) of input speech frames. Learned embeddings are then used in Gaussian mixture model based hierarchical clustering for diarization. The results show that these unsupervised embeddings are better compared to MFCCs in reducing the diarization error rate. Experiments conducted on the popular subset of the …


Efficient Features For Smartphone-Based Iris Recognition, Ritesh Vyas, Tirupathiraju Kanumuri, Gyanendra Sheoran, Pawan Dubey Jan 2019

Efficient Features For Smartphone-Based Iris Recognition, Ritesh Vyas, Tirupathiraju Kanumuri, Gyanendra Sheoran, Pawan Dubey

Turkish Journal of Electrical Engineering and Computer Sciences

Iris recognition has widely been used in personal authentication problems. Recent advances in iris recognition through visible wavelength images have paved the way for the use of this technology in smartphones. Smartphone-based iris recognition can be of significant use in financial transactions and secure storage of sensitive information. This paper presents a hybrid representation scheme for iris recognition in mobile devices. The scheme is called hybrid because it firstly makes use of Gabor wavelets to reveal the texture present in the normalized iris images, and then extracts statistical features from different partitions of Gabor-processed images. The standard mobile-iris database, called …


A Depth-Based Nearest Neighbor Algorithmfor High-Dimensional Data Classification, Sandhya Harikumar, Akhil A.S, Ramachandra Kaimal Jan 2019

A Depth-Based Nearest Neighbor Algorithmfor High-Dimensional Data Classification, Sandhya Harikumar, Akhil A.S, Ramachandra Kaimal

Turkish Journal of Electrical Engineering and Computer Sciences

Nearest neighbor algorithms like k-nearest neighbors (kNN) are fundamental supervised learning techniques to classify a query instance based on class labels of its neighbors. However, quite often, huge volumes of datasets are not fully labeled and the unknown probability distribution of the instances may be uneven. Moreover, kNN suffers from challenges like curse of dimensionality, setting the optimal number of neighbors, and scalability for high-dimensional data. To overcome these challenges, we propose an improvised approach of classification via depth representation of subspace clusters formed from high-dimensional data. We offer a consistent and principled approach to dynamically choose the nearest neighbors …


Devonian-Carboniferous Brachiopods And Biostratigraphic Findings From The Kangal Phyllite-Slate Formation (Greenschist), Sivas, Turkey, Cazi̇be Sayar, Ali̇ Seydi̇ Gülteki̇n, Mustafa Si̇mav Bargu, Esra Alkan Jan 2019

Devonian-Carboniferous Brachiopods And Biostratigraphic Findings From The Kangal Phyllite-Slate Formation (Greenschist), Sivas, Turkey, Cazi̇be Sayar, Ali̇ Seydi̇ Gülteki̇n, Mustafa Si̇mav Bargu, Esra Alkan

Turkish Journal of Earth Sciences

The Kangal Phyllite-Slate Formation forms the basement rocks in Kangal-Çetinkaya-Alacahan-Divriği (Sivas). These late Paleozoic phyllite-slate associations occupy a large area, possibly composed of Early Paleozoic sediments in its lower part. The lower levels (Bakırtepe Metaquartzite Member; 0-500 m) and uppermost levels comprise the Düzce Recrystallized Limestone Member (0-25 m). The lower boundary is invisible and the upper boundary is unconformably overlain by the Kıratgediği Limestone (late Jurassic- early Cretaceous). The studied brachiopod fauna, about 400 specimens, was collected from the 150-m-thick uppermost part of the greenschist sequences in the Kulluk Hill area, Elkondu village, 25 km east of Kangal. Some …


Convergence-Aligned Foreland Magmatism In The Arabia-Anatolia Collision:Geochronological Evidence From The Karacadağ Volcanic Complex, South-East Turkey, Taner Eki̇ci̇, Colin G. Macpherson Jan 2019

Convergence-Aligned Foreland Magmatism In The Arabia-Anatolia Collision:Geochronological Evidence From The Karacadağ Volcanic Complex, South-East Turkey, Taner Eki̇ci̇, Colin G. Macpherson

Turkish Journal of Earth Sciences

New 40Ar/39Ar ages are presented for volcanic rocks from the Karacadağ Volcanic Complex (KVC) in SE Anatolia. These extend the oldest age recognised for the KVC for lavas from the Siverek Phase plateau basalt back to at least 17 Ma. Our data agree with prior studies that the second, Karacadağ Phase of igneous activity began at about 4.5 Ma with a peak between 2 and 1 Ma, but in contrast to previous work we find that this included volcanism on the Mt. Karacadağ ridge from the earliest part of this phase. Construction of the Mt. Karacadağ ridge coincided with development …


Primary Report Of First Documentation Of Mammal Footprints From The Late Oligocene Inthe Sivas Basin, Turkey, Beki̇r Levent Mesci̇, Ahmet Cem Erkman, Şaki̇r Önder Özkurt Jan 2019

Primary Report Of First Documentation Of Mammal Footprints From The Late Oligocene Inthe Sivas Basin, Turkey, Beki̇r Levent Mesci̇, Ahmet Cem Erkman, Şaki̇r Önder Özkurt

Turkish Journal of Earth Sciences

The footprints in this study, which were considered to have been made by ungulates, were discovered on mudstone that was approximately 5 cm thick, near an abundant mud-cracked plane located on the stratigraphic subsurface of the late Oligocene Karayün Formation, which crops out over wide areas in southern Sivas (Turkey) and has terrestrial, fluvial sediment characteristics. These ungulate footprints documented from the late Oligocene of the Karayün Formation in southern Sivas represent the first reported vertebrates in Anatolia. The footprints of three different species of ungulates were identified. The shapes, depth, and widths of the footprints provided some basic ichnotaxonomic …


Frequency-Dependent Body-Q And Coda-Q In Karlıova Triple Junction And Its Vicinity,Eastern Turkey, Alper Demi̇rci̇ Jan 2019

Frequency-Dependent Body-Q And Coda-Q In Karlıova Triple Junction And Its Vicinity,Eastern Turkey, Alper Demi̇rci̇

Turkish Journal of Earth Sciences

A dataset obtained from six broadband stations of 111 small- to moderate-sized local events that occurred between 2010 and 2018 was analyzed to reveal the frequency-dependent seismic body (body-Q) and coda (coda-Q) wave attenuation characteristics of three tectonic branches of the Karlıova Triple Junction: the Varto Fault Zone (VFZ), North Anatolian Fault Zone (NAFZ), and East Anatolian Fault Zone. The magnitude range was between 2.8 and 6.1 with shallow (


Miocene Sediment Mineralogy Of The Lower Chelif Basin (Nw Algeria):Implications For Weathering And Provenance, Fatiha Hadji, Abbas Marok, Ali Mokhtar-Samet Jan 2019

Miocene Sediment Mineralogy Of The Lower Chelif Basin (Nw Algeria):Implications For Weathering And Provenance, Fatiha Hadji, Abbas Marok, Ali Mokhtar-Samet

Turkish Journal of Earth Sciences

Mineralogical investigations of clay and nonclay minerals were conducted on the Miocene sediments from three sections of the lower Chelif basin, northern Algeria. Bulk rock analyses of Miocene sediments show that these clastic sediments are dominated by variable mineralogical compositions and concentrations. Quartz is the dominant mineral through the three stratigraphic intervals and calcite (except in the upper layers) and dolomite are lacking in the Messinian deposits. The clay mineralogy is dominated by smectite (24%) and mixed-layer illite-smectite (I-S) (22%) during the Burdigalian-Langhian, illite (36%) and kaolinite (28%) in the Tortonian, and illite (49%) and I-S (20%) in the Messinian …


Relationship Between The Anisotropy Of Magnetic Susceptibility And Development Of The Haymana Anticline, Central Anatolia (Turkey), Murat Özkaptan, Erhan Gülyüz Jan 2019

Relationship Between The Anisotropy Of Magnetic Susceptibility And Development Of The Haymana Anticline, Central Anatolia (Turkey), Murat Özkaptan, Erhan Gülyüz

Turkish Journal of Earth Sciences

Integrated structural and anisotropy of magnetic susceptibility (AMS) analyses were carried out on the Campanian- Maastrichtian shale-mudstone dominated sedimentary sequences (Haymana Formation) cropping out within the doubly plunging Haymana Anticline in Central Anatolia (Turkey). In order to understand the relationship between the development of magnetofabrics and the tectonic processes, six sites from different parts of the anticline were sampled and analyzed. AMS lineations from 634 cylindrical samples and structural data were collected in the field. The results show very high correlation with the structural trend of the region and indicate that the maximum susceptibility vector (k1) is almost parallel to …


Sedimentological And Mineralogical Characteristics Of Red Soil In South Pirin Mountains(Southwest Bulgaria), Rossitza Kenderova, Ahinora Baltakova, Marlena Yaneva Jan 2019

Sedimentological And Mineralogical Characteristics Of Red Soil In South Pirin Mountains(Southwest Bulgaria), Rossitza Kenderova, Ahinora Baltakova, Marlena Yaneva

Turkish Journal of Earth Sciences

The northernmost derivation of the Mediterranean climatic influence and the wide distribution of carbonate rocks are factors that could explain red soils distribution in the lands of Southern Bulgaria. However, due to the mainly mountainous landscape, red soils can be found only on certain spots in Bulgaria. One of the most typical examples of red soil can be found in the lands of Nova Lovcha Village in Bulgaria, but this area was not studied in detail due to its border position. In this study, the catena principle was used to estimate the parental material and slope drainage relationships as factors …


Application Of Zircon Typology Method To Felsic Rocks (Cappadocia, Central Anatolia, Turkey): A Zircon Crystallization Temperature Perspective, Lütfi̇ye Akin, Erkan Aydar, Axel Karl Schmitt, Hüseyi̇n Evren Çubukçu Jan 2019

Application Of Zircon Typology Method To Felsic Rocks (Cappadocia, Central Anatolia, Turkey): A Zircon Crystallization Temperature Perspective, Lütfi̇ye Akin, Erkan Aydar, Axel Karl Schmitt, Hüseyi̇n Evren Çubukçu

Turkish Journal of Earth Sciences

Zircon typology was developed nearly half a century ago as a tool for constraining the thermochemical conditions in granitic magmas from the morphology of zircon prismatic and pyramidal crystal surfaces. Although the method precedes experimentally constrained zircon-based thermometers (zircon saturation, Ti-in-zircon), the morphology of zircon remains an important criterion for zircon studies commonly relying on visual recognition of crystals during sample purification via hand-picking. This may introduce selection bias if morphologically distinct zircon crystals are present in a population. We conducted a comparison between zircon typology and thermochemical constraints from zircon thermometry and whole rock compositions. Therefore, we focused on …


Structure Of The Büyük Menderes Graben Systems From Gravity Anomalies, Emre Ti̇mur, İlknur Kaftan, Coşkun Sari, Müjgan Şalk Jan 2019

Structure Of The Büyük Menderes Graben Systems From Gravity Anomalies, Emre Ti̇mur, İlknur Kaftan, Coşkun Sari, Müjgan Şalk

Turkish Journal of Earth Sciences

The Büyük Menderes Graben (BMG) of western Turkey is bounded by E-W oriented normal faults and has been a depositional center for thick sedimentary layers since the Miocene. Four Mio-Pliocene depressions (from west to east, the Çine, Bozdoğan, Karacasu, and Denizli basins) having overall N-S trends are situated just south of the BMG. In this study, we focused on the structural characteristics of the BMG using Bouguer gravity data covering the area between 37°N and 39°N and 26°30'E and 30°E and gravity data along 4 profiles to estimate the discontinuous basement relief of the BMG. Our main objectives were to …


Modification Of Biomass-Derived Activated Carbon With Magnetic $\Alpha $-Fe$_{2}$O$_{3}$ Nanoparticles For Co$_{2}$ And Ch$_{4}$ Adsorption, Çi̇sem Kirbiyik Jan 2019

Modification Of Biomass-Derived Activated Carbon With Magnetic $\Alpha $-Fe$_{2}$O$_{3}$ Nanoparticles For Co$_{2}$ And Ch$_{4}$ Adsorption, Çi̇sem Kirbiyik

Turkish Journal of Chemistry

Magnetic and nonmagnetic activated carbons (ACs) were successfully prepared by using AC obtained from spent coffee grounds (SCGs) for use in CO$_{2}$ and CH$_{4}$ capture. SCGs were activated by chemical activation to produce ACs and a magnetic $\alpha $-Fe$_{2}$O$_{3}$/AC composite was prepared by coprecipitation method from the ACs produced. Magnetic and nonmagnetic samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDX) techniques. The textural properties of samples were determined by nitrogen adsorption-desorption using the Brunauer--Emmett--Teller (BET) and Barrett--Joyner--Halenda (BJH) methods. The results showed that the porosity of …


The Early Eocene Ekmekçi Granodiorite Porphyry In The Karacabey Region(Sakarya Zone, Nw Turkey), Gürsel Sunal, Mehmet Korhan Erturaç, Gülteki̇n Topuz, Aral Okay, Thomas Zack Jan 2019

The Early Eocene Ekmekçi Granodiorite Porphyry In The Karacabey Region(Sakarya Zone, Nw Turkey), Gürsel Sunal, Mehmet Korhan Erturaç, Gülteki̇n Topuz, Aral Okay, Thomas Zack

Turkish Journal of Earth Sciences

The Ekmekçi granodiorite porphyry is a unit in the E-W trending, postcollisional Eocene magmatic rocks of northern Anatolia. It occurs as a relatively small stock, but represents a link between plutonic and volcanic rocks. This Early Eocene granodiorite porphyry intruded into the Upper Triassic rocks of the Karakaya complex in the Sakarya Zone. In this study we present geochemical and zircon U-Pb LA-ICP-MS age data to contribute to understanding the Early Tertiary postcollisional tectonic setting of NW Anatolia. The granodiorite porphyry includes plagioclase, quartz, hornblende, K-feldspar, biotite, and minor zircon, apatite, sphene, and opaque minerals. The stock displays medium-K calc-alkaline …


Petrography, Geochemistry, And Provenance Of Jurassic Sandstones From Thesakarya Zone, Nw Turkey, Firat Şengün, Osman Ersi̇n Koralay Jan 2019

Petrography, Geochemistry, And Provenance Of Jurassic Sandstones From Thesakarya Zone, Nw Turkey, Firat Şengün, Osman Ersi̇n Koralay

Turkish Journal of Earth Sciences

The Jurassic sandstones exposed in the western part of the Sakarya Zone are yellowish to brown, moderate to well sorted, medium to coarse-grained, grain-supported, and cemented by calcareous and minor silica. Sandstones are mainly classified as litharenite, subarkose, and arkose according to the relative proportions of quartz, feldspar and rock fragments, and major element ratios. On the SiO2 variation diagram, Na2O and K2O show slight positive correlations, which could reflect abundance of sodic plagioclase and K-feldspar with quartz within high Si-content sandstones. Sandstones generally exhibit slight LREE enrichment with respect to HREEs. The REE plots are characteristic for sedimentary rocks …