Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Akpinar, Adem(4)
- Dokuz, Abdurrahman(3)
- Kandemir, Raif(3)
- Kömürcü, Murat Ihsan(3)
- Merdan, Mehmet(3)
- Yildirim, Ahmet(3)
- Ali, Ahmed H.(2)
- Arslan, Mehmet(2)
- Cevik, U.(2)
- Chung, Sun-Lin(2)
- Demir, Yilmaz(2)
- Eyuboglu, Yener(2)
- Gökdogan, Ahmet(2)
- Karsli, Orhan(2)
- Sadiklar, M. Burhan(2)
- Santosh, M.(2)
- Sen, Cueneyt(2)
- Sipahi, Ferkan(2)
- Supuran, Claudiu T.(2)
- Topal, Fevzi(2)
- Uysal, Ibrahim(2)
- Çelik, Necati(2)
- Abdulqader, Abdulqader S.(1)
- Acar, Ramazan(1)
- Akal, Cueneyt(1)
- Akaryali, Enver(1)
- Akpinar, A.(1)
- Aktarer, Semih Mahmut(1)
- Aliyazicioǧlu, Yüksel(1)
- Alkan, Hamdi(1)
- Alçiçek, Mehmet Cihat(1)
- Andersen, Tom(1)
- Apaydin, Gokhan(1)
- Arslan, M.(1)
- Aslan, Z.(1)
- Aydin, Faruk(1)
- Aydinçakir, Emre(1)
- Aytekin, Mustafa(1)
- Ayzit, Tolga(1)
- Açikel, Selami(1)
Yayınlar
- MakaleYalnız künye2026Artificial Neural Network-Based prediction of production cross sections of the medical radioisotopes 67Ga and 89Zr
Okutan, Murat; Üncü, Yigit Ali; Sevim, Gencay; Sekerci, Mert; Kiliçarslan, Tolga; Demir, Bayram; Ozdogan, Hasan
In this study, the excitation functions of the 67Zn(p,n)67Ga, 68Zn(p,2n)67Ga, and 89Y(p,n)89Zr reactions were investigated. Nuclear reaction simulations were performed using the TALYS 1.95 and EMPIRE 3.2 codes, by using Two Component Exciton Model, Geometry Dependent Hybrid Model, Exciton Model, and Hybrid Monte Carlo Simulation. In parallel, a feedforward artificial neural network (ANN) trained with the Levenberg-Marquardt (LM) algorithm was employed to predict the same reaction cross-sections using experimental data. Comparative analysis revealed a strong consistency between TALYS and EMPIRE calculations, ANN predictions, and experimental results, with the ANN providing enhanced predictive performance in energy regions where experimental data are sparse or uncertain. Furthermore, activation and yield calculations confirmed the feasibility of producing clinically relevant quantities of 67Ga and 89Zr under realistic irradiation conditions. In conclusion, the use of physics-based nuclear reaction codes with data-driven ANN models has been demonstrated to be useful in medical radionuclide production studies by providing a complementary framework for cross-section estimation.
- MakaleAçık Erişim2026Comparative study of magnetic and electric quadrupole moments in boron (5B) isotopes
Ali, Ahmed H.; Tfiha, Amir D.; Zakaly, Hesham M. H.; Jarallah, Naz T.; Issa, Shams A. M.; Abdulqader, Abdulqader S.; Çelik, Necati; Bhuyan, M.
The magnetic moments and electric quadrupole moments of the B-5 isotopes were calculated using different nuclear interactions and sets of effective charges. Instead of relying on core polarization, the effective charges were adopted through a microscopic theoretical approach. The one-body density matrix (OBDM) elements for these isotopes were calculated using the NuShellX@MSU code. The calculations were carried out within the shell model framework, using both the p- and psd-model spaces (MS). These model spaces were selected for nuclei with proton number Z = 5 and neutron number N > 3. The theoretical results for magnetic and quadrupole moments were compared with available experimental data. Theoretical magnetic moments of the B-8,B-10,B-11,B-12,B-13 isotopes showed good agreement with experiment when using the p-MS with the pwt interaction, and the psd-MS with the psdmwk interaction. Similarly, the theoretical electric quadrupole moments reasonably well with the experimental values when using the p-MS with the pkuo interaction, and the psd-MS with the psdmwk interaction.
- MakaleAçık Erişim2026A combined Monte Carlo, analytical, and experimental study of true coincidence summing correction factors for 152Eu
Çelik, Necati; Ali, Ahmed H.; Apaydin, Gokhan; Çevik, Ugur; Açikel, Selami
The radionuclide 152Eu presents a significant challenge in gamma-ray spectrometry due to its complex decay scheme and significant true coincidence summing (TCS) effects, especially in close-measurement geometries. This study presents a comprehensive investigation into TCS correction factors for the principal gamma-ray lines of 152Eu using tripartite methodology: a custom Monte Carlo (MC) simulation based on the EGS4 system, an established analytical method, and direct experimental measurements. The MC simulation explicitly models the complete decay process, including branching ratios, gamma emissions, internal conversion, and subsequent X-ray emissions for both decay branches (beta-minus to 152Gd and EC to 152Sm). Experimentally, correction factors were derived using a well-characterized point source measured at multiple distances with a coaxial HPGe detector. The analytical, method based on probabilistic analysis of the decay scheme, served as an examination. Results demonstrate that the analytical method underestimated the TCS correction factors, particularly for low-energy lines such as 121.78 keV, where it predicted a mere 0.78 % correction compared to 25.5 and 23.5 % from MC and experiment, respectively. This discrepancy is attributed to the analytical method's neglect of gamma-X ray coincidences and the internal conversion effects. In contrast, the MC simulation showed remarkable agreement with experimental results across all energies, validating its capability to accurately model the full complexity of TCS effects. The study concludes that while analytical methods offer rapid estimates, MC simulations, especially when experimentally validated, are essential for achieving metrological accuracy in the gamma-ray spectrometric analysis of complex radionuclides like 152Eu.
- MakaleYalnız künye2026Tomography of the source zone of the February 6, 2023, Kahramanmaras, Earthquake Doublets of Southern Anatolia
Salah, Mohamed K.; Alkan, Hamdi; Öztürk, Serkan; Güney, Recep
On February 6, 2023, two destructive earthquakes and many posterior aftershocks hit the Kahramanmaras,area in southern Anatolia. The Kahramanmaras, earthquake sequence (KMES) caused extensive damage and economic losses in T & uuml;rkiye and Syria. In this study, the 3-D crustal seismic velocities surrounding the hypocentral region of the KMES are determined using a large dataset of body wave arrival times obtained from local earthquakes. To better constrain the physical properties and seismogenic behavior of the KMES source region, the Vp/Vs ratio is calculated and correlated with Poisson's ratio using the obtained velocity models. To gain a better understanding of the stress conditions and regional earthquake activity in the study area, the depth variation of the b-value is also examined. The velocity structure is generally heterogeneous with both low and high velocities at upper crustal depths. Along the East Anatolian Fault Zone and its environs, low-velocity anomalies are charted. Also, small b-values (<1.0) are estimated in the region encompassing the KMES, especially at upper crustal depths. The KMES source zone is characterized by low b-value, low to average Vp, low Vs, and average/high Vp/Vs ratios. Hit count rates and the resolution test show that the mapped velocity anomalies are robust down to a depth of 45 km. Therefore, the moderate/high Vp/Vs and small b-values at the upper and middle crustal depths along the EAFZ may give constraints on the next earthquake hazards of the study region. The present findings provide deeper insight into the physical properties and the seismogenic potential of the crustal zones in proximity to the active fault segments of the Anatolian Plateau and the northwestern part of Arabia.
- MakaleYalnız künye20263-D magnetotelluric modeling and radiogenic heat reservoir for EGS development: A case study of the Kestanbol Granitoid intrusion (NW Türkiye)
Büyük, Ersin; Hacioglu, Ozlem; Ayzit, Tolga; Baba, Alper
Enhanced Geothermal Systems (EGS) provide firm, low-carbon baseload power and can contribute to reducing fossil-fuel-based energy generation. Granites and granitoids are particularly favourable EGS hosts due to their widespread occurrence, fracture-controlled permeability, and long-term heat supply from radiogenic decay. This study proposes an EGS development plan for the Kestanbol Granitoid Intrusion (KGI) in NW Anatolia, T & uuml;rkiye, based on a three-dimensional magnetotelluric (MT) model integrated with geochemical constraints on radiogenic heat production (RHP). We invert MT data acquired at fifty unevenly spaced sites to image the 3D resistivity structure of the KGI and its surroundings, resolving a highly resistive plutonic body bounded by relatively conductive fault-fracture zones. To quantify the radiogenic heat reservoir, we determine RHP rates from uranium, thorium, and potassium concentrations measured on twenty-seven rock samples from the KGI and adjacent lithologies, and integrate these values with the MT-derived pluton geometry. When combined with the regional stress regime, the integrated results indicate that the KGI hosts elevated RHP relative to surrounding rocks and that its internal structure and fault-controlled permeability architecture are favourable for EGS development. In particular, the north-western margin of the KGI emerges as the most promising target for injection-production well pairs. This workflow demonstrates how integrated MT, geochemical, and structural analyses can provide a quantitative, site-specific basis for EGS prospect ranking and drilling strategy in radiogenic granite/granitoid provinces. Overall, we propose a site-specific and risk-aware EGS development plan for the KGI that couples subsurface structure, radiogenic heat supply, and permeability architecture, providing a transferable framework for assessing radiogenic granite/granitoid provinces.
- MakaleYalnız künye2026Computational gamma-ray attenuation and fast-neutron removal cross-section assessment of CrN, AlCrN and AlTiCrN ceramic coatings using EGS4 Monte Carlo and Phy-X/PSD
Sirin, Murat; Kaya, Selim; Aktarer, Semih Mahmut; Baltas, Hasan; Küçükömeroglu, Tevfik
In this study, the computationally predicted gamma-ray attenuation behavior and fast-neutron removal cross-section characteristics of micrometre-scale CrN, AlCrN, and AlTiCrN ceramic coatings produced via cathodic arc evaporation were investigated. The shielding parameters were not measured by direct gammaor neutron-transmission experiments; instead, mass attenuation coefficients (MAC, mu/rho) in the 0.05-2.50 MeV range were obtained from EGS4 Monte Carlo simulations and Phy-X/PSD calculations, and the agreement between the two computational datasets was evaluated. Energy-dependent attenuation parameters, including half-value layer (HVL), mean free path (MFP), effective atomic number (Zeff), radiation protection efficiency (RPE), and kerma coefficients, were calculated. Statistical comparison showed good consistency between EGS4 and Phy-X/PSD for MAC, RPE, HVL, MFP, and kerma coefficients, whereas Zeff exhibited larger method-dependent deviations. All coatings showed higher attenuation at low photon energies due to the photoelectric effect, while Compton scattering dominated at intermediate energies. Among the investigated coatings, CrN exhibited the most favorable calculated gamma-ray attenuation indicators, with lower HVL and MFP values and higher RPE values. The macroscopic fast-neutron removal cross-section (Sigma R) was also calculated as a first-order neutron attenuation indicator, and CrN showed the highest Sigma R value. Considering their limited thickness of approximately 2.3-2.8 mu m, these coatings should not be regarded as replacements for conventional bulk radiation shields. Instead, nitride-based ceramic coatings may serve as secondary or multifunctional surface layers in space-restricted components requiring local radiation attenuation and mechanical durability.
- MakaleAçık Erişim2024Revisiting the depositional age and provenance characteristics of metasedimentary rocks from the basement units in the Central Pontides (N Turkey): New constraints for tectonic evolution of the southern Black Sea region
Cimen, Okay; Gucer, Mehmet Ali; Akal, Cueneyt; Goncueoglu, Mehmet Cemal; Arslan, Mehmet; Simonetti, Antonio; Karaoglan, Fatih
The pre -Jurassic tectonic evolution of the Central Pontides in northern Turkey is still poorly understood due to the lack of detailed geochemical and geochronological data from the basement units. Therefore, this study reports for the first time combined whole rock geochemistry, trace element data and U-Pb ages for detrital zircons, and Ar-Ar geochronological data from the metasedimentary rocks of the Devrekani Massif, Geme Complex, and the Serve & ccedil;ay Unit to better understand their provenance, depositional age characteristics, and tectonic evolutions. The detrital zircon U-Pb data of metasedimentary units from the Devrekani Massif, Geme Complex, and the Serve & ccedil;ay Unit yield ca. 191, 185 and 298 Ma maximum depositional ages (youngest age peaks), respectively. The Devrekani Massif is dominated by Permo-Carboniferous-aged detrital zircons (67 %), whereas Neoproterozoic and Devonian -aged detrital zircons are more common in the Geme Complex (47 %) and the Serve & ccedil;ay Unit (53 %). These distinct age distributions clearly indicate that the Devrekani Massif may has been deposited in a dissimilar location compared to the Geme Complex and the Serve & ccedil;ay Unit. Furthermore, in contrast to the Devrekani Massif, the source area of the metasedimentary rocks from the Geme Complex is comparable with that of the Serve & ccedil;ay Unit. Lastly, the obtained detrital zircon U-Pb and mica Ar-Ar ages suggest that the Devrekani Massif and the Geme Complex were deposited and metamorphosed during the Early and Middle Jurassic, respectively. The Serve & ccedil;ay Unit was deposited and metamorphosed in the Permian.
- MakaleYalnız künye2023Post-Variscan autochthonous cover in the eastern Sakarya Zone, Turkey: Evolution of the late Carboniferous back-arc ocean to the Triassic Karakaya Ocean
Dokuz, Abdurrahman; Alçiçek, Mehmet Cihat; Tunçdemir, Vahdet; Kandemir, Raif; Aydinçakir, Emre
The processes that caused removal of the upper Carboniferous to Permian sediments in the eastern Sakarya Zone, Turkey, are modeled by using of geochemical data and LA-ICP-MS U-Pb ages from detrital zircons. A felsic provenance and passive margin setting during the deposition of the upper Carboniferous catalcesme sediments are inferred from the geochemistry of sandstones (SiO2 > 85 wt%). Chemical Index of Alteration (CIA) values (75 - 81) indicate warm and humid climatic conditions and tectonic tranquility during deposition. Fifty-three (58%) concordant zircon grains produce a youngest age population in the range of 308.7 +/- 4.4 to 342.1 +/- 6.9 Ma, typical for the Variscan events. The burgundy color and upward-fining in clast size and bed thickness are the most prominent features of the concordantly overlying Hardisi Formation. Geochemistry (SiO2 = 66-81 wt%) and CIA values (58-65) of the clastic rocks point to a subduction-related tectonic setting and increasing rate of erosion in the source area. We highlight that the catalcesme sediments were deposited in a back-arc basin opened to the south of a continental ribbon separated from Gondwana. Approaching of the Paleotethyan mid-ocean ridge to the subduction zone was resulted in flattening in subducting slab, which in turn caused the back-arc basin to migrate into the interior parts of Gondwana and the former back-arc basin to evolve into a lacustrine setting. Increase in the elevation of source areas was resulted in an increase in the rate of physical erosion and trans-portation of burgundy Hardisi clastic sediments into the lacustrine basin.
- MakaleAçık Erişim2020Tracking the timing of Neotethyan oceanic slab break-off: Geochronology and geochemistry of the quartz diorite porphyries, NE Turkey
Karsli, Orhan; Dokuz, Abdurrahman; Aydin, Faruk; Uysal, Ibrahim; Sengün, Firat; Kandemir, Raif; Santos, Jose Francisco; Andersen, Tom
The initiation of the break-off of the northern branch of the Neotethyan oceanic lithosphere is an important but poorly understood event in the geology of the Sakarya Zone (SZ) in northeastern Turkey. Although it is wellknown that Latest Cretaceous intrusives (-70 Ma) and early Eocene adakitic magmatic rocks are present in the eastern SZ, the outcrops of the early Eocene non-adakitic rocks are very limited, and their tectono-magmatic evolution has not been studied. We describe a small outcrop of non-adakitic quartz diorite porphyry in the Kov area of the Gumushane region in northeastern Turkey. The genesis of these porphyries is significant in evaluating the syn-to post-collision-related magmatism. The LA-ICP-MS zircon U-Pb dating revealed that the Kov quartz diorite porphyries (KQDP) formed at ca. 50 Ma, coeval with adakitic rocks, and-20 Myr later than the slab rollback-related intrusive rocks. The KQDPs are calc-alkaline in composition and enriched in large ion lithophile elements (LILEs) and light rare earth elements (LREEs) and depleted in high field strength elements (HFSEs; e.g., Nb, Ta, Ti), with significant negative anomalies of Nb, Ta, and Ti but positive anomalies of Th, U, and Pb. Isotopic compositions of the samples show limited range of variation and slight enrichment of 87Sr/86Sr(t) (0.70489 to 0.70555), epsilon Nd(t) (-1.4 to -1.2) with TDM of 1.11 to 1.61 Ga. Pb isotopic ratios of the samples point to an enriched mantle source. They were likely crystallized from the melt that originated from an EM2-type spinel-facies subcontinental lithospheric mantle (SCLM), followed by the fractionation with insignificant crustal assimilation. The SCLM was metasomatically enriched, and the metasomatic agent was likely H2O-rich fluids rather than sediments released from subducting oceanic crust during the Late Cretaceous closure of the Neotethyan oceanic lithosphere. In conjunction with the geological background and previous data, we propose that the generation of the KQDPs resulted from a slab break-off event that caused ascending or infiltration of hot asthenosphere, triggering mantle melting. Such sporadic occurrences of the KQDPs, with coeval adakitic rocks in the SZ, are likely associated with the onset of extensional tectonics due to the earlier stage of slab break-off along the region during the early Eocene period.
- MakaleYalnız künye2020Mineralogy, chemistry, and genesis of zeolitization in Eocene tuffs from the Bayburt area (NE Turkey): Constraints on alteration processes of acidic pyroclastic deposits
Cicerali, Derya; Arslan, Mehmet; Yazar, Emel Abdioglu; Yücel, Cem; Temizel, Irfan; Park, Sohyun; Schroeder, Paul A.
Eocene vitric tuffs in the Bayburt area (NE Turkey) possess a dacite-rhyodacite composition and contain abundant altered glass shards and flattened fibrous pumice with lesser amounts of pyrogenic minerals (plagioclase, quartz, biotite, and sanidine). Zeolitization is common and generally develops in the glassy components. The main zeolite mineral found in the tuffs is clinoptilolite, with lesser amounts of analcime and mordenite (?). Smectite is the dominant clay mineral, with lesser amounts of kaolinite also present. Opal-CT, calcite, and dolomite occur as secondary minerals. Scanning electron microscopy studies reveal the dissolution of glass, with the development of popcorn-textured smectites and tabular clinoptilolites developed. The opal-CT spheres found on the clinoptilolite crystals appear to have crystallized simultaneously and are due to excess silica in the environment. Fibrous mordenite (?) also developed on the clinoptilolites. In the clinoptilolites R-r = 0.81-0.82, Si/Al = 4.20-4.70, and K+ is the dominant exchangeable cation (0.65-3.30) seen, together with lesser amount of Ca2+ (0.39-2.25) and Na+ (0.02-2.16). The degree of zeolitization increases with the content of glassy component in the tuffs. The formation of K-clinoptilolite is controlled by the SiO2/Al2O3 (4.9-7.0) and K2O/Na2O (0.8-10.8) ratios in the zeolitized tuffs. delta O-18(V-SMOW) and delta DV-SMOW values of clinoptilolite-rich tuffs range from 22 to 25.6960 and from -96 to -111 parts per thousand, respectively, which suggests that zeolitization occurred at low temperatures (30-55 degrees C) via fluid-rock interactions. Smectite was initially formed from the devitrification of glassy components and is associated with the increase in (Na+ +K+ +Ca2+)/H+ activity and the presence of high pH similar to-9-10) fluids. The zeolites subsequently developed within a saline-alkali shallow marine environment.
- MakaleYalnız künye2017Petrogenesis of ultramafic rocks from the eastern Orhaneli ophiolite, NW Turkey: Hints on the initiation and evolution of melt-peridotite interaction processes within a heterogeneously depleted mantle section
Uysal, Ibrahim; Dokuz, Abdurrahman; Kapsiotis, Argyrios; Saka, Samet; Karsli, Orhan; Kaliwoda, Melanie; Mueller, Dirk
The eastern Orhaneli ophiolite in NW Anatolia (Turkey) consists of voluminous dunite and minor harzburgite intruded by clinopyroxenite veins. Harzburgite contains spinel of low Cr# [100 x Cr/(Cr + Al) = 40-45] and diopside of low Al2O3 and TiO2 contents, whereas dunite contains spinel of higher Cr# (62-82) and diopside (blebs) (even more) depleted in Al2O3 and TiO2 (than harzburgite). The concentrations of Heavy Rare Earth Elements (HREE) in harzburgite are consistent with derivation of this type of peridotite from 19% dry melting of a fertile mantle protolith at a MOR regime. Dunites have lower concentrations of HREE than harzburgite implying that dunites were generated by higher degrees (> 30%) of (cumulative) melting of the same protolith. Furthermore, the characteristic U-shapes of the chondrite-normalized REE-patterns of dunites indicate the involvement of hydrous melt-peridotite interaction processes in their genesis. Nevertheless, a set of mosaic-in texture dunite samples contain olivine that has lower Fo# [100 x Mg/(Mg + Fe2+)] and NiO contents than olivine in harzburgite. These dunites are probably of cumulate origin as it is also indicated by their enrichment in Pt and Pd (<= 17.92 ppb). Micro-textural and Re-Os isotopic data support that clinopyroxenite intrusions do not have a pure magmatic origin and their formation was partly controlled by metasomatic processes. Overall data indicate that the eastern Orhaneli ultramafic rocks have a complex petrological history including various stages of partial melting, metasomatism and magmatism in an evolving from MOR to SSZ geotectonic setting.
- MakaleYalnız künye2014Synthesis of cyclohexane derivatives including Br, Cl, N, O, and S at 1,2,4,5-positions: Selectivity in addition reactions Dedicated to Professor Dr. Metin Balci on the occasion of his 65th anniversary
Kaya, Afşin Ahmet; Menzek, Abdullah; Şahin, Ertan
Brominations of mono addition products of 1,4-cyclohexadiene with 2,4-dinitrobenzenesulfenyl chloride (RSCl) selectively gave 1R(S),2R(S),4R(S), 5R(S)-4,5-dibromo-2-(2,4-dinitrophenylthio)cyclohexyl acetate and 1R(S),2R(S),4R(S),5R(S)-4,5-dibromo-2-chlorocyclohexyl)(2,4-dinitrophenylthio) sulfane. From series reactions 7-oxabicyclo[4.1.0]hept-3-ene with reagents, such as RSCl, NaN3, and H2SO4/Ac2O, six 1,2,4,5-tetrasubstituted cyclohexane derivatives including S, O, N, Cl, and Br were selectively obtained. Formations and structures of the products were discussed.
- MakaleAçık Erişim2014Oxidation of cyanobenzocycloheptatrienes: Synthesis, photooxygenation reaction and carbonic anhydrase isoenzymes inhibition properties of some new benzotropone derivatives
Güney, Murat; Coskun, Ahmet; Topal, Fevzi; Dastan, Arif; Gülçin, Ilhami; Supuran, Claudiu T.
The oxidation of some cyanocycloheptatrienes with CrO3 and pyridine was investigated and a few new nitrile functionalised benzotropone derivatives were obtained. Photooxygenation reaction of these products was also studied. The structures of the formed products were determined on the basis of NMR spectroscopy and the formation mechanism of unusual products was discussed. Human carbonic anhydrase isoenzymes I, and II (hCA I and hCA II) inhibition properties of nitrile functionalized new benzotropone derivatives were also studied. Both CA isozymes were inhibited in the low micromolar range by these nitrile functionalized benzotropone analogues. The newly synthesized benzotropone derivatives showed inhibition constants in the sub-micromolar range (2.51-4.06 mu M). The best hCA I inhibition was observed in 5H-benzocycloheptene-7-carbonitrile (K-1: 2.88 +/- 0.86 mu M). On the other hand, 5-oxo-5H-benzocycloheptatriene-7-carbonitrile showed the powerful inhibitory effect against hCA II (K-i: 2.51 +/- 0.34 mu M). (C) 2014 Elsevier Ltd. All rights reserved.
- MakaleAçık Erişim2013The effect of prenatal exposure to 900-MHz electromagnetic field on the 21-old-day rat testicle
Hanci, Hatice; Odaci, Ersan; Kaya, Haydar; Aliyazicioǧlu, Yüksel; Turan, Ibrahim; Demir, Selim; Çolakoǧlu, Serdar
The aim of this study was to investigate the effect of exposure to a 900-MHz electromagnetic field (EMF) in the prenatal term on the 21-old-day rat testicle. Pregnant rats were divided into control (CG) and EMF (EMFG) groups. EMFG was exposed to 900-MHz EMF during days 13-21 of pregnancy. Newborn CG rats were obtained from the CG and newborn EMFG (NEMFG) rats from the EMFG. Testicles were extracted at postnatal day 21. Lipid peroxidation and DNA oxidation levels, apoptotic index and histopathological damage scores were compared. NEMFG rats exhibited irregularities in seminiferous tubule basal membrane and epithelium, immature germ cells in the lumen, and a decreased diameter in seminiferous tubules and thickness of epithelium. Apoptotic index, lipid peroxidation and DNA oxidation were higher in NEMFG rats than in NCG. 21-day-old rat testicles exposed to 900-MHz EMF in the prenatal term may be adversely affected, and this effect persists after birth.
- MakaleYalnız künye2013The contribution of hydropower in meeting electric energy needs: The case of Turkey
Akpinar, Adem
In this article, an attempt is made to better understand the contribution of hydropower in meeting electric energy needs of Turkey. Thus, a comparison between Turkey and other countries, which have some similarities with Turkey or which are more developed nations compared to Turkey, for evaluating from different aspects the contribution of hydropower in meeting electric energy needs is performed. The producers of electricity and hydroelectricity in the world, and the electric sectors of all the selected countries are firstly examined. Thereafter, Turkey's water resources and its potential, hydropower potential, and current status of hydropower in Turkey are investigated in detail. A detailed discussion regarding economic and energy indicators, hydroelectricity versus thermal electricity, the contributions of hydroelectricity to the total and renewable electricity generation, and the usage status of hydro potential of each selected nation is also made. Finally, it is found that hydropower is the second largest contributor in meeting Turkey's electric energy needs after thermal, mainly natural gas. It is also estimated that the contribution of hydropower will continue because a vast amount of its economically feasible hydro potential (about 64%) is undeveloped. Besides, it is determined that the contribution of hydropower in the total electricity generation in Turkey is greater than that of China and India, but it is lower than that of Norway, Brazil, and Canada.
- MakaleYalnız künye2013Decaying source model: Alternative approach to determination of true counting rates at X and gamma ray counting systems
Karabidak, S.M.; Cevik, U.
The counting systems consisting of electronic devices are used for detection of radiation due to X or gamma rays. The dead time of the counting system is based on time limitations of these electronic devices. The dead time causes counting losses. Determination of counting rate losses in quantitative and qualitative analysis become a vital step for correction of analysis. Therefore, compensating for counting rate losses is of great importance. These counting rate losses are due to piled up reject time, paralyzable or non-paralyzable system dead time or a combination of these mechanisms. Paralyzable and non-paralyzable models are well-known and frequently used for correction of counting rate losses dependent on the system dead time. However, these two models do not provide enough correction at medium and high counting rates. Therefore, the new models for corrections of counting rate losses are needed. For this reason, both an alternative approach is proposed and a simulation program is coded for counting rate losses in this study. A good agreement is obtained between theoretical model and simulation program.
- Derleme MakaleYalnız künye2012RETRACTED: Regional sustainable water and energy development projects: A case of Southeastern Anatolia Project (GAP) in Turkey (Retracted article. See vol. 83, pg. 173, 2018)
Akpinar, A.; Kaygusuz, K.
Southeastern Anatolia Project (GAP) region in Turkey is rich in water for irrigation and hydroelectric power. The Euphrates and Tigris Rivers represent over 28% of the nation's water supply by rivers, and the economically irrigable areas in the region make up 20% of those for the entry country. Turkey has a total gross hydropower potential of 433 GWh/yr, but only 125 GWh/yr of the total hydroelectric potential of Turkey can be economically used. By the construction of new hydropower plants, 36% of the economically usable potential of the country would be tapped. The GAP region has a 22% share of the country's total hydroelectric potential, with plans for 22 dams and 19 hydroelectric power plants. Once completed, 27 billion kWh of electricity will be generated annually. (C) 2011 Elsevier Ltd. All rights reserved.
- Derleme MakaleYalnız künye2012Hydropower for sustainable energy development in Turkey: The small hydropower case of the Eastern Black Sea Region
Capik, Mehmet; Osman Ylmaz, Ali; Cavusoglu, Ibrahim
Turkey is a rich country from the point of variety and potential of renewable energy resources. Hydros, winds, biomass, solar and geothermal are important renewable and environmentally friendly sources for energy in Turkey. Turkey produces large amount of hydropower with a total gross hydropower potential of 433 TW h/yr, which is equal to 13.8% of the total hydropower potential of Europe. Technically useable potential is 216 TW h/yr and economic potential is 140 TW h/yr. The main aim of the present study is to investigate hydropower potential of Turkey and small hydropower plants in Eastern Black Sea Region for sustainable energy development in Turkey. The geography of Turkey especially, Eastern Black Sea Region supports and suitable the development of the small hydro plants to increase the energy generation and utilization of available water sources in Turkey. Besides, the paper deals with hydropower policies to meet ever increasing energy demand for sustainable development of Turkey.
- Derleme MakaleYalnız künye2012Present situation and potential role of renewable energy in Turkey
Çapik, Mehmet; Yilmaz, Ali Osman; Çavuşoĝlu, Ibrahim
Turkey has a rich potential of hydropower, wind and geothermal energy resources. The distribution of these renewable energy sources in operation are hydropower, wind and geothermal 14.802 MW 1002MW and 94 MW, respectively. Turkey possesses a huge hydroelectric resource which is one of the Turkey's major energy assets. Most of the important uses of water in power plants have been developed in the electricity generation. Turkey has a total gross hydropower potential of 433 TWh/yr, which is equal to 13.8% of the total hydropower potential of European. Technically useable and economic potential are 216 TWh/yr and 140 TWh/yr, respectively. The total share of all energy for electricity power generation in 2010 are coal, natural gas, fuel oil and renewable energy, 104,040 GWh, 125,549 GWh, 18,215 GWh, and 86,120 GWh respectively. Among the renewable energy resources in Turkey, biomass and solar energy are also important because their share in total energy consumptions have increased. On the other hand, Turkey has not utilized nuclear energy yet. The current government plans to have a nuclear power plant with a capacity of 1800MW at the Black Sea Port of Sinop. The main purpose of the energy policies is to answer the energy needs of increasing population and growing economy at minimum costs while making energy supply planning. Turkey's specific national energy strategy document and energy policy objectives are outlined in the institutional strategic plans. These strategic plans are energy supply security, regional and global influence in the area of energy and environment protection. The aim of energy policy including renewable are to develop existing energy sources and to avoid dependence on energy imports and to encourage private sector investment and to improve the reliability of electricity supply. The main aim this study will investigate at the present potential of energy resources and future contributions to the national energy consumption in Turkey. As result present energy situation, the renewable energy potential, and the energy politics of Turkey are investigated.
- MakaleYalnız künye2012Evaluation of the numerical wave model (SWAN) for wave simulation in the Black Sea
Akpinar, Adem; van Vledder, Gerbrant Ph.; Kömürcü, Murat Ihsan; Özger, Mehmet
This study summaries the implementation of the SWAN model forced by the ECMWF ERA Interim dataset reanalyzed 10 m winds over the Black Sea which will be used to study the wind-wave climate and wave energy potential in the region, and its verification. The SWAN model results were compared with directional buoy measurements at three locations along the north and south coasts of the Black Sea, parametric model results based on the JONSWAP growth relations, and the results of previous studies. The SWAN model has been applied in a third generation and non-stationary mode with spherical coordinates. The linear and exponential growth from wind input, depth-induced wave breaking, bottom friction, whitecapping, four-wave (for deep water) and triad-wave (for shallow water) nonlinear interactions have been activated in the simulations. The results of this study indicate that agreement between simulated and observed wave parameters is satisfactory and it is slightly more accurate than the results of the previous studies. However, it still has lower estimates for the maximum values of both wave parameters. These lower estimates are probably due to too low wind speeds in the applied ECMWF wind fields, which is probably caused by orographic effects, and due to the relatively course resolution in time and space of the ECMWF (ERA-Interim) wind fields for the Black Sea. (C) 2012 Elsevier Ltd. All rights reserved.