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Multiple Period Search For K, M And C Type Semiregular Variables In Tübi̇tak National Observatory, Cahi̇t Yeşi̇lyaprak, Ti̇mur Şahi̇n, Ahmet İskender
Multiple Period Search For K, M And C Type Semiregular Variables In Tübi̇tak National Observatory, Cahi̇t Yeşi̇lyaprak, Ti̇mur Şahi̇n, Ahmet İskender
Turkish Journal of Physics
In this study, periods obtained from long-term multi-bands (Johnson V and R filters) photometric observations of some K, M and C spectral type semiregular (SR) variables obtained with the T40 telescope (40 cm) and SSP5A photometer at TÜBİTAK National Observatory (TNO) between 1998 and 2005 were examined. We have found that some of these SR variables have multiple (long and short) periods as appeared mostly from Hipparcos observations; three variables are, for the first time, observed to have a period. The light curves, the variation amplitude in R band and the maximum light Epoch(s) of SR variables were also given. …
Simultaneously Finite Size And Interaction Effects On A Harmonically Trapped ^{87}Rb Gas, Ahmed Sayed Hassan, Hassab Eldyeam Hadi
Simultaneously Finite Size And Interaction Effects On A Harmonically Trapped ^{87}Rb Gas, Ahmed Sayed Hassan, Hassab Eldyeam Hadi
Turkish Journal of Physics
In the framework of the semiclassical approximation (K_B T >> \hbar\Omega), an accurate ansatz formula for the density of states is suggested. This formula is able to include the finite size, interatomic interaction effects, and the role of dimensionality simultaneously. Condensed fraction, and average energy per particle for a condensed ^{87}Rb gas in anisotropic trap in 3D and 2D are calculated. The results for the above mentioned thermodynamic quantities show good agreement with the measured experimental results. Furthermore, full agreement is obtained with the other method used to calculate the same quantities.
The Study Of Copper Zinc Sulphide (Cuzns_2) Thin Films, Chidi Chukwuemeka Uhuegbu, Elisha Bamidele Babatunde, Cornelius O. Oluwafemi
The Study Of Copper Zinc Sulphide (Cuzns_2) Thin Films, Chidi Chukwuemeka Uhuegbu, Elisha Bamidele Babatunde, Cornelius O. Oluwafemi
Turkish Journal of Physics
Thin films of CuZnS_2 were successfully deposited on glass substrates from aqueous solution of copper chloride in which EDTA and TEA were used as complexing agents. The optical and solid state properties were studied include: absorbance, transmittance, reflectance, extinction coefficient, refractive index, absorption coefficient, optical conductivity, dielectric constants. The direct and indirect band gaps obtained ranges from 2.2 eV to 2.4 eV for direct band gap and 0.4 eV to 0.9 eV for indirect band gap. The possible applications were also mentioned.
Stability Effect In Photoconducting Studies Of Some Chemically Deposited Cds, (Cd-Pb)S And (Cd-Zn)S Films, Shashi Bhushan, Tandesh Chandra
Stability Effect In Photoconducting Studies Of Some Chemically Deposited Cds, (Cd-Pb)S And (Cd-Zn)S Films, Shashi Bhushan, Tandesh Chandra
Turkish Journal of Physics
Stability effects in photoconductivity (PC) rise and decay have been studied over a period of 2 years in thin films of (Cd-Pb)S:LiF, La/Pr and (Cd-Zn)S: LiF,La/Pr and have been found quite stable; however, those of CdS are not that stable. Results of annealing effect are also included, which present more stable values. XRD studies show prominent lines of base materials. Further, XRD and SEM studies show the particle sizes are in the nanometer range. Results of optical absorption spectra have been used to evaluate the band gap of the materials. Effect of thickness of the Ag electrode has also been …
Role Of Substrate Temperature On The Structural And Morphological Properties Of Zno Thin Films Deposited By Ultrasonic Spray Pyrolysis, Abdelkader Djelloul, Khadidja Bouzid, Fahima Guerrab
Role Of Substrate Temperature On The Structural And Morphological Properties Of Zno Thin Films Deposited By Ultrasonic Spray Pyrolysis, Abdelkader Djelloul, Khadidja Bouzid, Fahima Guerrab
Turkish Journal of Physics
Zinc oxide (ZnO) thin films have been prepared by ultrasonic Spray Pyrolysis (USP) technique using zinc acetate dihydrate dissolved in methanol, ethanol and deionized water. A thermodynamic analysis for the growth of ZnO thin films from zinc acetate and water vapor has been made. The evolution of the preferred crystalline orientations in the ZnO films was investigated systematically. The optical measurements reveal that films have a maximum transmittance of about 90% and a direct band gap of 3.26 eV.
Photo Organic Field Effect Transistor´S Properties, Khasan S. Karimov, Ibrahim N. Ibrahim, M. Mahroof Tahir, Tauseef Ahmed Khan, Umar Shafique
Photo Organic Field Effect Transistor´S Properties, Khasan S. Karimov, Ibrahim N. Ibrahim, M. Mahroof Tahir, Tauseef Ahmed Khan, Umar Shafique
Turkish Journal of Physics
A thin organic films of p-type semiconducting copper phthalocynanine (CuPc) film and semitransparent Al film were deposited in sequence by vacuum evaporation on glass substrate with Ag source and drain electrodes, fabricating an organic field effect transistor with metal (aluminum)-semiconductor (copper phthalocyanine) Schottky junction. The transistor was investigated for effect of illumination on its characteristics. It was found that the gate-source (Al-Ag) and gate-drain (also Al-Ag) dark current-voltage characteristics show rectification behavior. Under non-modulated filament-lamp illumination, photo-potential is developed between gate-source and gate-drain terminals. Drain current of this organic phototransistor (OPT) increased with illumination. An energy band diagram of the …
Sr And Nd Isotopic Characteristics Of Some S-, I- And A-Type Granitoids From Central Anatolia, Serhat Köksal, M. Cemal Göncüoğlu
Sr And Nd Isotopic Characteristics Of Some S-, I- And A-Type Granitoids From Central Anatolia, Serhat Köksal, M. Cemal Göncüoğlu
Turkish Journal of Earth Sciences
The petrogenesis of some Late Cretaceous S-, I- and A-type granitoids in the Aksaray and Kırşehir regions of Central Anatolia is investigated by means of whole-rock Sr and Nd isotope data with supplementary field, petrographic, and whole-rock geochemical studies. The S-type Central Anatolian granitoids (Sinandı and Namlıkışla) have calc-alkaline peraluminous characteristics and show LILE and LREE enrichment. The I-type Central Anatolian granitoids (Borucu, Terlemez, Hisarkaya, Baranadağ), on the other hand, are calc-alkaline (excepting the alkaline Baranadağ sample) and metaluminous or slightly peraluminous with LILE and LREE enriched patterns and variable Eu-anomalies. Additionally, the A-type Çamsarı granitoid is alkaline and metaluminous …
Crustal Structure Of The Eastern Part Of Central Anatolia (Turkey), Hüseyi̇n Yilmaz, Sevda Özel
Crustal Structure Of The Eastern Part Of Central Anatolia (Turkey), Hüseyi̇n Yilmaz, Sevda Özel
Turkish Journal of Earth Sciences
This study aims to examine crustal structure in the eastern part of central Anatolia using the magnetotelluric (MT) method. MT data have been collected from 37 stations along a north-south 220 km profile crossing in succession the Tokat Massif (Pontide basement), the Ankara-Erzincan Suture Zone, the Kırşehir Massif, the Pınarbaşı-Divriği Ophiolitic Belt and the Tauride-Anatolide Belt. Data were modelled to derive a geo-electrical model using 2-dimensional inverse techniques. Low resistivity values (981 Ohm.m) coincide with the southern part of the Pontide Magmatic Arc, the Kırşehir Block and the Tauride-Anatolide Belt and are interpreted as upper crust of igneous and metamorphic …
The Geochemistry And Setting Of The Demirci Paragneisses Of The Sünnice Massif, Nw Turkey, Erdi̇nç Yi̇ği̇tbaş, John A. Winchester, Christopher J. Ottley
The Geochemistry And Setting Of The Demirci Paragneisses Of The Sünnice Massif, Nw Turkey, Erdi̇nç Yi̇ği̇tbaş, John A. Winchester, Christopher J. Ottley
Turkish Journal of Earth Sciences
The Demirci migmatitic quartzofeldspathic gneisses of the Sünnice Massif, exposed in the İstanbul Zone north of Bolu, have compositions that show them to be paragneisses, associated with subordinate para-amphibolites. They consist principally of metamorphosed, rather calcareous greywackes, with sediment derived from a continental arc source. They occur in the para-autochthon below a nappe pile (Çele meta-ophiolite), deformed and subjected to amphibolite facies metamorphism before the emplacement of late Neoproterozoic metavolcanic rocks later subjected to greenschist-facies metamorphism (Yellice volcanics). As they are overlain in sequence by nappes comprising sections of the Çele meta-ophiolite with ocean floor basalt and island arc tholeiite …
Ankara Orogenic Phase, Its Age And Transition From Thrusting-Dominated Paleotectonic Period To The Strike-Slip Neotectonic Period, Ankara (Turkey), Ali̇ Koçyi̇ği̇t, Şule Deveci̇
Ankara Orogenic Phase, Its Age And Transition From Thrusting-Dominated Paleotectonic Period To The Strike-Slip Neotectonic Period, Ankara (Turkey), Ali̇ Koçyi̇ği̇t, Şule Deveci̇
Turkish Journal of Earth Sciences
The Ankara section of the İzmir-Ankara-Erzincan Suture Zone (IAESZ) is characterized by two major groups of contractional structures, namely the Ankara forced folds-monoclines and the southward-verging foreland fold-imbricate thrust to reverse fault zone (AFITFZ). In the Ankara region, one of the areas where the various phases of deformation and related structures are particularly well-preserved and exposed is the Edige (Elmadağ) area, 48 km east-southeast of the city of Ankara. The youngest palaeotectonic unit in the AFITFZ, and deformed in the last phase of the palaeotectonic period (the Ankara orogenic phase) is the Edige formation. It consists of a fluvio-lacustrine sedimentary …
The R/V Meteor Cruise Leg M44/1 In February 1999 In The Sea Of Marmara: The First Multibeam Bathymetric Study And Analysis Of Methane In Sediment And Water Columns, İsmai̇l Kuşçu, Peter Halbach, Maik Inthorn, Thomas Kuhn, Richard Seifert
The R/V Meteor Cruise Leg M44/1 In February 1999 In The Sea Of Marmara: The First Multibeam Bathymetric Study And Analysis Of Methane In Sediment And Water Columns, İsmai̇l Kuşçu, Peter Halbach, Maik Inthorn, Thomas Kuhn, Richard Seifert
Turkish Journal of Earth Sciences
During the first leg of R/V Meteor cruise M44 in February 1999, geoscientific studies in two areas in the Sea of Marmara were carried out. The studies mainly focused on cool fluid and gas (mainly methane) emanations in the deepest zones of the Sea of Marmara along the northern strand of the North Anatolian Fault Zone, which were particularly expected because of the availability of fault zones as a preferential pathway for fluid migration. Fluids and gases both within the pore water and the benthic water were investigated through long cores and water samples to reveal their relationship with the …
Timing Of The Quaternary Elazığ Volcanism, Eastern Turkey, And Its Significance For Constraining Landscape Evolution And Surface Uplift, Ali̇ Seyrek, Rob Westaway, Malcolm Pringle, Sema Yurtmen, Tuncer Demi̇r, George Rowbotham
Timing Of The Quaternary Elazığ Volcanism, Eastern Turkey, And Its Significance For Constraining Landscape Evolution And Surface Uplift, Ali̇ Seyrek, Rob Westaway, Malcolm Pringle, Sema Yurtmen, Tuncer Demi̇r, George Rowbotham
Turkish Journal of Earth Sciences
The eastern part of the Anatolian plateau in eastern Turkey has experienced dramatic landscape evolution in the Late Cenozoic, surface uplift having been associated with the disruption of former lake basins and the development of the modern high-relief landscape, incised by the upper reaches of the River Euphrates and its major tributary, the Murat. Overall, the altitude of the plateau decreases gradually westward, and it has been assumed that uplift on any given timescale has varied regionally in a similar manner. However, using the Ar-Ar method, we have dated an episode of basaltic volcanism around the city of Elazığ to …
Thematic Set: Active Tectonics And Earthquake Hazard Of Western Anatolia -- Preface, Hasan Sözbi̇li̇r, Serdar Akyüz, Erhan Altunel, Hali̇l Gürsoy
Thematic Set: Active Tectonics And Earthquake Hazard Of Western Anatolia -- Preface, Hasan Sözbi̇li̇r, Serdar Akyüz, Erhan Altunel, Hali̇l Gürsoy
Turkish Journal of Earth Sciences
No abstract provided.
Isostatic Compensation In Western Anatolia With Estimate Of The Effective Elastic Thickness, Oya Pamukçu, Ayça Yurdakul
Isostatic Compensation In Western Anatolia With Estimate Of The Effective Elastic Thickness, Oya Pamukçu, Ayça Yurdakul
Turkish Journal of Earth Sciences
Isostasy is concerned with how the crust and mantle adjusts to shifting loads of limited spatial and temporal dimensions. By analysing the frequency content of gravity and topography data, it has been possible to determine the compensation scheme of a region. In this study, the compensation mechanism of the Western Anatolia, which has dynamic loads, was investigated by isostatic response functions. Effective elastic thickness in Western Anatolia region was estimated based on admittance and coherence between gravity and topography data. The two most reliable indicators of lithospheric strength are the focal depth distribution of earthquakes and relation of gravity anomalies …
Earthquake Hazard Of The Aegean Extension Region (West Turkey), Orhan Polat, Elçi̇n Gök, Doğuser Yilmaz
Earthquake Hazard Of The Aegean Extension Region (West Turkey), Orhan Polat, Elçi̇n Gök, Doğuser Yilmaz
Turkish Journal of Earth Sciences
West Turkey, one of the most seismically active regions of Turkey, has been analysed to reveal seismic hazard by using fractal behaviour, seismic quiescence z- and Gutenberg-Richter b-parameters. Starting from raw earthquake catalogue, we performed completeness analysis on recorded events, and a final catalogue, could be accepted as homogeneous, was obtained. According to the results obtained from the Frequency-Magnitude Distribution (FMD), seismic activity rates (b- and z-values) and fractal correlation dimension, we detected three anomalous zones throughout the Aegean Extension Region (AER). These are: (1) Çandarlı Bay and Bergama-Zeytindağ Fault Zone, (2) İzmir fault and Orhanlı Fault Zone, and (3) …
In Memoriam Jean Philippe Marcoux, A.M. Celal Şengör
In Memoriam Jean Philippe Marcoux, A.M. Celal Şengör
Turkish Journal of Earth Sciences
No abstract provided.
Stratigraphic And Structural Evidence For Fault Reactivation: The Active Manisa Fault Zone, Western Anatolia, Çağlar Özkaymak, Hasan Sözbi̇li̇r
Stratigraphic And Structural Evidence For Fault Reactivation: The Active Manisa Fault Zone, Western Anatolia, Çağlar Özkaymak, Hasan Sözbi̇li̇r
Turkish Journal of Earth Sciences
In this paper, we aim to present stratigraphic and structural evidence for fault reactivation that is linked with evolution of the western part of the Manisa fault zone - a major range-bounding fault that is geomorphologically expressed as a trace of north-facing scarps bounding the southern margin of the Manisa basin which is subsidiary to the Gediz Graben. We identify that the Manisa fault zone, at its western end, consists of three fault segments which are en échelon arranged in left step. Each segment is identified as steep topographic scarps visible on topographic maps and in landsat images. Fault scarps …
The Ampullinid Gastropod Globularia (Swainson 1840) From The Late Thanetian-Early Ilerdian Kırkkavak Formation (Polatlı-Ankara) Of The Tethyan Realm, Yavuz Okan, İzzet Hoşgör
The Ampullinid Gastropod Globularia (Swainson 1840) From The Late Thanetian-Early Ilerdian Kırkkavak Formation (Polatlı-Ankara) Of The Tethyan Realm, Yavuz Okan, İzzet Hoşgör
Turkish Journal of Earth Sciences
Ampullinid gastropods are useful in correlating the Palaeogene marine strata of Central Anatolia. Ampullinid gastropods are found in the Late Paleocene-Early Eocene Kırkkavak Formation in the Macunköy area (Polatlı, west of Ankara). In the Haymana-Polatlı Basin, a variety of Globularia (Swainson 1840) species is described from the upper part of the Kırkkavak Formation, including G. sireli n.sp. The other taxa are G. vapincana (d´Orbigny 1850), G. grossa (Deshayes 1864) and G. crassatina (Lamarck 1804). The Kırkkavak fauna is known in western and central Europe, and central Asia. Some of the ampullinid gastropods and associated cerithid and neritid gastropods as well …
Some Bulk Viscous String Cosmological Models, Ganeshwar Mohanty, Gauranga Charana Samanta
Some Bulk Viscous String Cosmological Models, Ganeshwar Mohanty, Gauranga Charana Samanta
Turkish Journal of Physics
Five dimensional String cosmological models in the presence of variable bulk viscous coefficient, constant bulk viscous coefficient and in the absence of bulk viscosity are constructed and some physical and kinematical behaviors of these models are discussed.
Generation Of High-Repetition-Rate Pulses Utilizing Cascaded Single Mode Fiber And Semiconductor Optical Amplifier, Jianwei Wu, Hai-Bo Bao
Generation Of High-Repetition-Rate Pulses Utilizing Cascaded Single Mode Fiber And Semiconductor Optical Amplifier, Jianwei Wu, Hai-Bo Bao
Turkish Journal of Electrical Engineering and Computer Sciences
To generate high-repetition-rate optical pulses, a novel and simple device is demonstrated, in which the cascaded single mode fiber (SMF) with negative third order dispersion and semiconductor optical amplifier (SOA) are adopted. Numerical research results show that let an optical pulse with center wavelength in zero dispersion wavelength of optical fiber transit in SMF for generating an oscillation pulse. Subsequently, the followed SOA is provided for amplification. As a consequence, the high-repetition-rate optical pulses can be obtained.
A Study On The Reliability Of Polyester Insulators Blended With Borax, Aysel Ersoy, Yasi̇n Özcelep, Ayten Kuntman
A Study On The Reliability Of Polyester Insulators Blended With Borax, Aysel Ersoy, Yasi̇n Özcelep, Ayten Kuntman
Turkish Journal of Electrical Engineering and Computer Sciences
Tracking is the main factor which limits the safe working electric stress of insulation in power system applications. Polymer samples have been tested in laboratory conditions according to ASTM D2303 on accelerated inclined plane tracking test. In this paper, a model based on improved Weibull statistics is proposed for estimating the breakdown time of polymeric insulating materials with borax. The confidence intervals of the Weibull shape parameter and the Weibull scale parameter are determined for the borax concentration values using the Weibull 7++ program.
Desert Rocks – A Habitat Which Supports Many Species That Were New To Science In The Last 40 Years, Avinoam Danin
Desert Rocks – A Habitat Which Supports Many Species That Were New To Science In The Last 40 Years, Avinoam Danin
Turkish Journal of Botany
Hard limestone, dolomite, sandstone, and granite constitute, under certain conditions, smooth-faced outcrops in desert areas of SW Asia. This habitat supports the most rare plant species in the desert including most of the desert endemics of Israel, Sinai, and Jordan. The smooth-faced outcrops efficiently contribute runoff water to the rock crevices and events when water is available for plant utilisation take place at a higher frequency than in the other habitats in the desert. In many sites plants are isolated and protected by impermeable rocks from competition from other plants. The rare and special plants found in this habitat include …
Recent Advances In Perfectly Matched Layers In Finite Element Applications, Özlem Özgün, Mustafa Kuzuoğlu
Recent Advances In Perfectly Matched Layers In Finite Element Applications, Özlem Özgün, Mustafa Kuzuoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
We present a comparative evaluation of two novel and practical perfectly matched layer (PML) implementations to the problem of mesh truncation in the finite element method (FEM): locally-conformal PML, and multi-center PML techniques. The most distinguished feature of these methods is the simplicity and flexibility to design conformal PMLs over challenging geometries, especially those with curvature discontinuities, in a straightforward way without using artificial absorbers. These methods are based on specially- and locally-defined complex coordinate transformations inside the PML region. They can easily be implemented in a conventional FEM by just replacing the nodal coordinates inside the PML region by …
Trace Classes And Fixed Points For The Extended Modular Group \Overline{\Gamma}, Özden Koruoğlu, Recep Şahi̇n, Sebahatti̇n İki̇kardeş
Trace Classes And Fixed Points For The Extended Modular Group \Overline{\Gamma}, Özden Koruoğlu, Recep Şahi̇n, Sebahatti̇n İki̇kardeş
Turkish Journal of Mathematics
The extended modular group \overline{\Gamma}=PGL(2,\mathbb{Z}) is the group obtained by adding the reflection R(z)=1/\overline{z} to the generators of the modular group \Gamma =PSL(2, {Z}). In this paper, we find the trace classes of the extended modular group \overline{\Gamma}. Using this, we classify the elements of \overline{\Gamma}.
On The Regular Elements In Z_N, Osama Alkam, Emad Abu Osba
On The Regular Elements In Z_N, Osama Alkam, Emad Abu Osba
Turkish Journal of Mathematics
All rings are assumed to be finite commutative with identity element. An element a \in R is called a regular element if there exists b \in R such that a=a^2b, the element b is called a von Neumann inverse for a. A characterization is given for regular elements and their inverses in Z_n, the ring of integers modulo n. The arithmetic function V(n), which counts the regular elements in Z_n is studied. The relations between V(n) and Euler's phi-function \varphi (n) are explored.
Linear Connections On Light-Like Manifolds, Teki̇n Dereli̇, Şahi̇n Koçak, Murat Li̇moncu
Linear Connections On Light-Like Manifolds, Teki̇n Dereli̇, Şahi̇n Koçak, Murat Li̇moncu
Turkish Journal of Mathematics
It is well-known that a torsion-free linear connection on a light-like manifold (M,g) compatible with the degenerate metric g exists if and only if Rad(TM) is a Killing distribution. In case of existence, there is an infinitude of connections with none distinguished. We propose a method to single out connections with the help of a special set of 1-forms by the condition that the 1-forms become parallel with respect to this connection. Such sets of 1-forms could be regarded as an additional structure imposed upon the light-like manifold. We consider also connections with torsion and with non-metricity on light-like manifolds.