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Articles 5101 - 5130 of 10319
Full-Text Articles in Physical Sciences and Mathematics
Mineralogy, Geochemistry, And Depositional Environment Of The Beduh Shale(Lower Triassic), Northern Thrust Zone, Iraq, Faraj Tobia, Sirwa Shangola
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, …
Mineral Chemistry Of Igneous Rocks In The Lar Cu-Mo Prospect, Southeastern Part Of Iran: Implications For P, T, And ÆO2, Rahele Moradi, Mohammad Boomeri, Sasan Bagheri, Kazuo Nakashima
Mineral Chemistry Of Igneous Rocks In The Lar Cu-Mo Prospect, Southeastern Part Of Iran: Implications For P, T, And ÆO2, 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 …
Distribution Of Natural Radioactivity And Assessment Of Radioactive Dose Of Western Anatolian Plutons, Turkey, Argyrios Papadopoulos, Şafak Altunkaynak, Antonis Koroneos, Alp Ünal, Ömer Kamaci
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.
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
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, …
Late Quaternary Chronostratigraphy Of The Aegean Sea Sediments: Special Reference To The Ages Of Sapropels S1?S5, Ekrem Bursi̇n İşler, Richard Nicholas Hiscott, Ali̇ Engi̇n Aksu
Late Quaternary Chronostratigraphy Of The Aegean Sea Sediments: Special Reference To The Ages Of Sapropels S1?S5, Ekrem Bursi̇n İşler, Richard Nicholas Hiscott, Ali̇ Engi̇n Aksu
Turkish Journal of Earth Sciences
Four sapropel layers (S1, S3, S4, and S5) are identified in five 6-10-m-long piston cores collected from the Aegean Sea basins. A chronostratigraphic framework is established for the last ~130 ka using benthic and planktonic foraminiferal oxygen isotope curves, total organic carbon contents, volcanic ash layers, and limited radiocarbon dates. These data show that the onsets of sapropels S3, S4, and S5 in the Aegean Sea basins were not synchronous, highlighting the heterogeneity of the Aegean Sea basins in terms of rapid versus lagged responses to changing ocean-climate boundary conditions. In all cases, however, the development of sapropels S3, S4, …
Tracking The Uplift Of The Bolkar Mountains (South-Central Turkey): Evidence From Apatite Fission Track Thermochronology, Fati̇h Karaoğlan
Tracking The Uplift Of The Bolkar Mountains (South-Central Turkey): Evidence From Apatite Fission Track Thermochronology, Fati̇h Karaoğlan
Turkish Journal of Earth Sciences
Apatite fission track (AFT) thermochronology is applied to the Horozköy granitoid, which outcrops within the Bolkar Mountains (south-central Turkey). The region comprises the Niğde Massif to the north, the Inner Tauride Suture Zone, and the Central Taurides to the south. The Niğde Massif and the Central Taurides collided during the Eocene following north-dipping subduction of the Inner Tauride Ocean beneath the Niğde Massif. The Ulukışla Basin formed above this suture zone. The AFT ages range between 23 and 16 Ma, although there was no significant uplift or exhumation during this period. During the Oligo-Miocene, the region experienced a slow uplift …
Nummulitic Facies Of The Crimean-Caucasian Region, Ekaterina A. Lygina, Pavel A. Fokin, Ludmila F. Kopaevich, Anatoly M. Nikishin, Elena V. Yakovishina
Nummulitic Facies Of The Crimean-Caucasian Region, Ekaterina A. Lygina, Pavel A. Fokin, Ludmila F. Kopaevich, Anatoly M. Nikishin, Elena V. Yakovishina
Turkish Journal of Earth Sciences
The nummulitic limestones of Crimea and the southwestern Caucasus, often interpreted as "nummulite banks", formed carbonate platforms throughout most of the Ypresian-Lutetian. Such deposits were accumulated in shallow warm-water basins of Crimea and the Caucasus, which differed from each other by the structure of the basement and the hydrodynamic regime. The Crimean carbonate platform was relatively flat and was formed mainly within quiet hydrodynamic conditions below the fair-weather wave base (less than 50 m). The facies changes within it reflect variations in water depth. Facies distinguished there form the nummulite bank, its lee-side slope, the shelf plain in the rear …
Stratigraphic Evidence For Development Of Aptian Intrashelf Basin In The Zagros Area, Eastern Fars Province, Sw Iran, Neda Khoshfam, Hossain Rahimpour-Bonab, Davoud Jahani, Davoud Morsalnezhad
Stratigraphic Evidence For Development Of Aptian Intrashelf Basin In The Zagros Area, Eastern Fars Province, Sw Iran, Neda Khoshfam, Hossain Rahimpour-Bonab, Davoud Jahani, Davoud Morsalnezhad
Turkish Journal of Earth Sciences
?The Lower Cretaceous of the Arabian Platform is renowned for the development of intrashelf basins. The study area is located in eastern Fars Province on the northeast Arabian plate and has experienced this environmental condition. The present study investigated two surface sections (Genau and Anguru) of the Dariyan Formation and compared the results with three neighboring wells in eastern Fars (eastern Zagros Fold Belt) in southern Iran to determine the development of rudist-bearing carbonates and intrashelf basin sediments. The Dariyan Formation was deposited in the Aptian as shallow-to-deep water carbonate facies. Lagoon, rudist banks/barriers, and open marine/basinal facies and six …
Geological, Geochemical, And Fluid Inclusion Evidences For The Origin Of The Ravanj Pb?Ba?Ag Deposit, North Of Delijan City, Markazi Province, Iran, Mostafa Nejadhadad, Batoul Taghipour, Alireza Zarasvandi, Alireza Karimzadeh Somarin
Geological, Geochemical, And Fluid Inclusion Evidences For The Origin Of The Ravanj Pb?Ba?Ag Deposit, North Of Delijan City, Markazi Province, Iran, Mostafa Nejadhadad, Batoul Taghipour, Alireza Zarasvandi, Alireza Karimzadeh Somarin
Turkish Journal of Earth Sciences
The Lower Cretaceous sequences of the Ravanj anticline in Iran host the Ravanj Pb-Ba-Ag mineralization. Economic orebodies are restricted to the thrust zone within the brecciated massive limestone and immediately above the Jurassic shale and/or shale-limestone intercalations of the Lower Cretaceous. Paragenetic sequence and distinct zoning of mineral assemblages indicate that ore-forming fluid migrated through thrust zones along the NE-trending faults. The REE pattern of mineralized host rock is characterized by HREE-enrichment ((La/Lu)PAAS = 0.24). The Ce/Ce* ratio of mineralized host samples shows negative Ce anomalies, which is most likely inherited from seawater. The positive Eu/Eu* anomaly suggests high ?O2 …
The Depth Effect Of Earthquakes On Tsunami Heights In The Sea Of Okhotsk, Andrey Zaytsev, Irina Kostenko, Andrey Kurkin, Efim Pelinovsky, Ahmet Cevdet Yalçiner
The Depth Effect Of Earthquakes On Tsunami Heights In The Sea Of Okhotsk, Andrey Zaytsev, Irina Kostenko, Andrey Kurkin, Efim Pelinovsky, Ahmet Cevdet Yalçiner
Turkish Journal of Earth Sciences
The earthquake of magnitude Mw = 8.3 that occurred on 24 May 2013 in the Sea of Okhotsk was the most powerful earthquake in the region. Fortunately, the generated tsunami was small because of the deep focal depth (609 km) and was only detected by the nearest Deep-ocean Assessment and Reporting of Tsunamis (DART) buoy records. However, the event highlighted the fact that any earthquakes with similar magnitudes at shallower focal depths would have caused considerable tsunamis. In order to evaluate the effects of possible tsunamis in the Sea of Okhotsk, we simulated water displacements due to the 24 May …
The New Empirical Magnitude Conversion Relations Using An Improved Earthquake Catalogue For Turkey And Its Near Vicinity (1900-2012), Fi̇li̇z Tuba Kadi̇ri̇oğlu, Recai̇ Feyi̇z Kartal
The New Empirical Magnitude Conversion Relations Using An Improved Earthquake Catalogue For Turkey And Its Near Vicinity (1900-2012), Fi̇li̇z Tuba Kadi̇ri̇oğlu, Recai̇ Feyi̇z Kartal
Turkish Journal of Earth Sciences
Empirical magnitude conversion relationships are one of the important parameters for not only seismological studies but also seismic hazard analysis and development of the attenuation relationships. Particularly, for seismic hazard analysis, conversion of various types of magnitudes to moment magnitude, which is the most reliable and common magnitude scale, is a key requirement. Within this scope, different magnitude conversion equations have been derived by various researchers in the literature. In this study, new empirical magnitude conversion formulas for conversion from mb, ML, Md, and MS to Mw were derived by using a recently established earthquake catalogue. The most important feature …
Geochemistry Of The Metavolcanic Rocks From The Çangaldağ Complex In The Central Pontides: Implications For The Middle Jurassic Arc-Back-Arc System In The Neotethyan Intra-Pontide Ocean, Okay Çi̇men, Mehmet Cemal Göncüoğlu, Kaan Sayit
Geochemistry Of The Metavolcanic Rocks From The Çangaldağ Complex In The Central Pontides: Implications For The Middle Jurassic Arc-Back-Arc System In The Neotethyan Intra-Pontide Ocean, Okay Çi̇men, Mehmet Cemal Göncüoğlu, Kaan Sayit
Turkish Journal of Earth Sciences
The Çangaldağ Complex in northern central Turkey is one of the main tectonic units of the Central Pontide Structural Complex that represents the remains of the poorly known Intra-Pontide branch of the Neotethys. It comprises low-grade metamorphic rocks of intrusive, extrusive, and volcaniclastic origin displaying a wide range of felsic to mafic compositions. Petrographically the complex consists of basalts-andesites-rhyodacites and tuffs with minor amount of gabbros and diabases. On the basis of geochemistry, the Çangaldağ samples are of subalkaline character and represented by both primitive and evolved members. All rock types are variably depleted in Nb compared to LREEs, similar …
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
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, …
Planktonic Foraminiferal Biostratigraphy And Quantitative Analysis During The Campanian-Maastrichtian Transition At The Oued Necham Section (Kalâat Senan, Central Tunisia), Ezzedine Saïdi, Dalila Zaghbib-Turki
Planktonic Foraminiferal Biostratigraphy And Quantitative Analysis During The Campanian-Maastrichtian Transition At The Oued Necham Section (Kalâat Senan, Central Tunisia), Ezzedine Saïdi, Dalila Zaghbib-Turki
Turkish Journal of Earth Sciences
The Oued Necham (ON) section (Kalâat Senan, central Tunisia) provides a well-exposed outcrop of a Campanian-Maastrichtian series that consists essentially of chalky limestones (i.e. the Abiod Formation) grading progressively to a marly unit (i.e. the El Haria Formation). The transitional Abiod-El Haria succession comprises a rich hemipelagic-pelagic fauna in the study area, but ammonites (e.g., Pachydiscus neubergicus, the Campanian/Maastrichtian (C/M) boundary index taxon) are scarce to absent, thus preventing the recognition of the standard zones defined for the Tethyan realm. However, the rich planktonic foraminiferal taxa of the El Haria Formation allow us to establish an accurate biostratigraphical scheme. Accordingly, …
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
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 …
A New Pelagic Conodont Taxon Of The Central Pontides (Turkey), Ali̇ Murat Kiliç
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.
A Study On $^{7}$Li + $^{120}$Sn Quasi-Elastic Scattering, Murat Aygün, Zeynep Aygün
A Study On $^{7}$Li + $^{120}$Sn Quasi-Elastic Scattering, Murat Aygün, Zeynep Aygün
Turkish Journal of Physics
In the present study, we reexamine quasi-elastic scattering of $^{7}$Li by $^{120}$Sn at incident energies E$_{Lab}$ = 19.5, 20.5, and 25.0 MeV. The theoretical results are obtained by using both a phenomenological model and double-folding model (DFM) within the framework of an optical model. We also investigate the role of the surface potential, which is connected to direct reactions. The agreement between the phenomenological model and the DFM is shown in comparison to each other in connection with the experimental data. This comparison provides information about the similarities and the differences between the models used during the calculations.
Supergravity Backgrounds And Symmetry Superalgebras, Ümi̇t Ertem
Supergravity Backgrounds And Symmetry Superalgebras, Ümi̇t Ertem
Turkish Journal of Physics
We consider the bosonic sectors of supergravity theories in ten and eleven dimensions corresponding to the low energy limits of string theories and M-theory. The solutions of supergravity field equations are known as supergravity backgrounds and the number of preserved supersymmetries in those backgrounds are determined by Killing spinors. We provide some examples of supergravity backgrounds that preserve different fractions of supersymmetry. An important invariant for the characterization of supergravity backgrounds is their Killing superalgebras, which are constructed out of Killing vectors and Killing spinors of the background. After constructing Killing superalgebras of some special supergravity backgrounds, we discuss the …
The Observational Status Of Simple Inflationary Models: An Update, Nobuchika Okada, Vedat Nefer Şenoğuz, Qaisar Shafi
The Observational Status Of Simple Inflationary Models: An Update, Nobuchika Okada, Vedat Nefer Şenoğuz, Qaisar Shafi
Turkish Journal of Physics
We provide an update on five relatively well-motivated inflationary models in which the inflaton is a Standard Model singlet scalar field. These include i) the textbook quadratic and quartic potential models but with additional couplings of the inflaton to fermions and bosons, which enable reheating and also modify the naive predictions for the scalar spectral index $n_s$ and $r$, ii) models with Higgs and Coleman-Weinberg potentials, and finally iii) a quartic potential model with nonminimal coupling of the inflaton to gravity. For $n_s$ values close to 0.96, as determined by the WMAP9 and Planck experiments, most of the considered models …
It Is Sufficient To Set The Cosmological Constant To Zero Or To A Small Number At An Initial Time, Recai̇ Erdem
It Is Sufficient To Set The Cosmological Constant To Zero Or To A Small Number At An Initial Time, Recai̇ Erdem
Turkish Journal of Physics
I point out a simple but usually overlooked fact about the cosmological constant problem: to solve the cosmological constant problem it is sufficient to find a symmetry or mechanism that sets the cosmological constant to zero or to a tiny value at some time in the past, provided that general relativity is the relevant theory of gravity, and the energy-momentum tensor (excluding the part of the form of a cosmological constant) is conserved. The relevant symmetry or mechanism need not be applicable today. Any additional cosmological constant term induced by a phase transition in the energy-momentum tensor in this case …
Geochemistry Of Aegean Sea Sediments: Implications For Surface- And Bottom-Water Conditions During Sapropel Deposition Since Mis 5, Ekrem Bursi̇n İşler, Ali̇ Engi̇n Aksu, Richard Nicholas Hiscott
Geochemistry Of Aegean Sea Sediments: Implications For Surface- And Bottom-Water Conditions During Sapropel Deposition Since Mis 5, Ekrem Bursi̇n İşler, Ali̇ Engi̇n Aksu, Richard Nicholas Hiscott
Turkish Journal of Earth Sciences
Piston cores collected from the Aegean Sea provide a record of sapropel sequence S1, S3-S5. Primary productivity calculations using the equations of Müller and Suess suggest surface paleoproductivities ranged from 180 to 995 g C m-2 year-1 for sapropels and from 40 to 180 g C m-2 year-1 for nonsapropel sediments with corresponding total organic carbon values of 9%-12% and 1%-3%, respectively. The higher paleoproductivities exceed those in the most fertile modern upwelling zones, so are probably overestimated. Instead, enhanced preservation, particularly for S4 and S5, likely resulted from poor bottom-water ventilation beneath a salinity-stratified water column. If the preservation …
Strike-Slip Neotectonic Regime And Related Structures In The Cappadocia Region: A Case Study In The Salanda Basin, Central Anatolia, Turkey, Ali̇ Koçyi̇ği̇t, Uğur Doğan
Strike-Slip Neotectonic Regime And Related Structures In The Cappadocia Region: A Case Study In The Salanda Basin, Central Anatolia, Turkey, Ali̇ Koçyi̇ği̇t, Uğur Doğan
Turkish Journal of Earth Sciences
The study area is a strike-slip basin of approximately 1-9 km wide, 66 km long and N65°W trending, located between the historical Kesikköprü in the west and the Sarıhıdır settlement in the east along the northern side of the Central Anatolian Volcanic Province. It was evolved on a regional erosional surface of a pre-Quaternary volcanosedimentary sequence during Quaternary. This is evidenced by the stratigraphical, structural, and seismic data. The total amounts of throw and dextral strike-slip displacement accumulated on the basin-boundary faults during the evolutionary history of the basin are 178 m and 5 km, respectively. The average slip rate …
Neutron Stars: Compact Objects With Relativistic Gravity, Kazim Yavuz Ekşi̇
Neutron Stars: Compact Objects With Relativistic Gravity, Kazim Yavuz Ekşi̇
Turkish Journal of Physics
General properties of neutron stars are briefly reviewed with an emphasis on the indispensability of general relativity in our understanding of these fascinating objects. In Newtonian gravity the pressure within a star merely plays the role of opposing self-gravity. In general relativity all sources of energy and momentum contribute to the gravity. As a result, the pressure not only opposes gravity but also enhances it. The latter role of pressure becomes more pronounced with increasing compactness, $M/R$, where $M$ and $R$ are the mass and radius of the star, and sets a critical mass beyond which collapse is inevitable. This …
Factorizations Related To The Reciprocal Pascal Matrix, Helmut Prodinger
Factorizations Related To The Reciprocal Pascal Matrix, Helmut Prodinger
Turkish Journal of Mathematics
The reciprocal Pascal matrix has entries $\binom{i+j}{j}^{-1}$. Explicit formul$\ae{}$ for its LU-decomposition, the LU-decomposition of its inverse, and some related matrices are obtained. For all results, $q$-analogues are also presented.
Some Results Concerning The Summability Of Spliced Sequences, Tuğba Yurdakadi̇m, Mehmet Ünver
Some Results Concerning The Summability Of Spliced Sequences, Tuğba Yurdakadi̇m, Mehmet Ünver
Turkish Journal of Mathematics
A spliced sequence is formed by combining all of the terms of two or more convergent sequences, in their original order, into a new spliced sequence. In this paper replacing convergent sequences by bounded sequences, we study the summability of spliced sequences and give some inequalities that provide us with approximation of the core of transformation of these sequences by a summability matrix. We also present some further results via the Lebesgue integral.
A Characteristic Particle Length, Mark D. Roberts
A Characteristic Particle Length, Mark D. Roberts
Turkish Journal of Physics
It is argued that there are characteristic intervals associated with any particle that can be derived without reference to the speed of light $c$. Such intervals are inferred from zeros of wavefunctions, which are solutions to the Schrödinger equation. The characteristic length is $\ell=\beta^2\hbar^2/(8Gm^3)$, where $\beta=3.8\dots$; this length might lead to observational effects on objects the size of a virus.
Enhancing Silicon Solar Cell Efficiency With Double Layer Antireflection Coating, Mohamed Medhat, El-Sayed El-Zaiat, Samy Farag, Gamal Youssef, Reda Alkhadry
Enhancing Silicon Solar Cell Efficiency With Double Layer Antireflection Coating, Mohamed Medhat, El-Sayed El-Zaiat, Samy Farag, Gamal Youssef, Reda Alkhadry
Turkish Journal of Physics
Antireflection coating on silicon, a high refractive index substrate, was theoretically investigated. The effects of antireflection coating on electrical parameters such as the short circuit current, open circuit voltage, maximum current density, maximum voltage, maximum power, power density, and conversion efficiency of the solar cell were simulated. Various previous works in which solar cell efficiencies were investigated after applying double layer antireflection coating (DLARC) were reviewed. Ti$_{2}$O$_{3}$ and MgF$_{2}$ were then applied in a DLARC design, taking into consideration the refractive index dispersion of the two materials. The results were compared with other works in the solar spectral range (400-1200 …
Radon Concentration Measurements At A University Campus In Turkey, Melekşah Altinsöz, Emel Alğin, Celal Aşici, Haci Soğukpinar
Radon Concentration Measurements At A University Campus In Turkey, Melekşah Altinsöz, Emel Alğin, Celal Aşici, Haci Soğukpinar
Turkish Journal of Physics
In this study we measured radon (222Rn) concentrations in offices at the Meşelik campus of Eskişehir Osmangazi University to estimate the effective dose of 222Rn and its progeny for office occupants. The measurements were performed four times in 2011 over a period of 3 months using solid state nuclear track detectors (LR-115). A total of 381 LR-115 detectors were installed in 110 different offices, choosing three offices on each floor in the same building. 222Rn concentrations obtained in the first, second, third, and fourth measurement periods were 163 (73) Bq m-3, 77 (43) Bq m-3, and 164 (70) Bq m-3 …
Exact Solutions To The Geodesic Equations Of Linear Dilaton Black Holes, Alan Hameed Hussein Hamo, Izzet Sakalli
Exact Solutions To The Geodesic Equations Of Linear Dilaton Black Holes, Alan Hameed Hussein Hamo, Izzet Sakalli
Turkish Journal of Physics
In this paper, we analyze the geodesics of the 4-dimensional linear dilaton black hole (LDBH) spacetime, which is an exact solution to the Einstein-Maxwell-dilaton theory. LDBHs have nonasymptotically flat geometry, and their Hawking radiation is an isothermal process. The geodesics motions of the test particles are studied via the standard Lagrangian method. After obtaining the Euler-Lagrange equations, we show that exact analytical solutions to the radial and angular geodesic equations can be obtained. In particular, it is shown that one of the possible solutions for the radial trajectories can be given in terms of the Weierstrass P-function ($\wp $-function), which …
Revisiting The Dyonic Majumdar-Papapetrou Black Holes, Seyedhabibollah Mazharimousavi, Mustafa Hali̇lsoy
Revisiting The Dyonic Majumdar-Papapetrou Black Holes, Seyedhabibollah Mazharimousavi, Mustafa Hali̇lsoy
Turkish Journal of Physics
We extend the Majumdar-Papapetrou solution of the Einstein-Maxwell equations, which are implied generally for static electric charge in nonrotating metrics, to encompass equally well magnetic charges. In the absence of Higgs and non-Abelian gauge fields, 'dyonic' is to be understood in this simpler sense. Cosmologically this may have far-reaching consequences, to the extent that existence of multimagnetic monopole black holes may become a reality in our universe. Infalling charged particle geodesics may reveal, through particular integrals, their inner secrets, which are screened from our observation.