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Koleksiyondaki öğeler
- MakaleAçık Erişim2025Scopus SJRQ2Insight into the adsorptive removal of Cr(VI) ions and 4-chlorophenol from aqueous media on cationic surfactant-modified cucumber peels
Ozeken, Sengul Tugba; Ozdes, Duygu; Duran, Celal
A new and cost-effective adsorbent material was developed by chemical modification of cucumber peels (CP) with a cationic surfactant, cetyltrimethylammonium bromide (CTAB). The adsorptive behavior of CTAB-modified cucumber peels (CMCP) was investigated in the retention of an organic pollutant (4-chlorophenol) and an inorganic pollutant (Cr(VI)) through batch experiments. The adsorbents were characterized by Fourier transform infrared spectroscopy (FTIR) analysis and scanning electron microscopy (SEM) technique. Influences of initial concentrations of both pollutants, dosage of CMCP, initial solution pH, contact time, and foreign ions were parameters used to specify the optimized conditions. Results of the experiments were evaluated by three kinetic models, namely pseudo-first-order, pseudo-second-order, and intraparticle diffusion models, to find out the dominant mechanisms in the retention of 4-chlorophenol and Cr(VI). Langmuir, Freundlich, and Dubinin–Radushkevich isotherm models were applied to the adsorption data to estimate the adsorption capacity of CMCP and to describe the interactions between the species. Langmuir isotherm model fitted the data well, and the maximum Cr(VI) and 4-chlorophenol adsorption capacities of CMCP were 84.03 mg g−1 and 107.5 mg g−1, respectively. Consequently, CMCP demonstrated outstanding performance in the adsorption of both inorganic and organic pollutants, offering a low-cost, easily prepared alternative to other adsorbents reported in the literature.
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İncele - MakaleAçık Erişim2026Scopus SJRQ2Evaluation of antioxidant and antiproliferative activities of shogaol and its modulatory effects on key metabolic enzymes
Yapıcı, İsmail; Gülçin, İlhami
Phenolic compounds are versatile bioactive molecules, particularly in food applications. In this study, the antioxidant capacity of Shogaol, a member of the phenolic class, was evaluated using several methods. Additionally, its inhibitory effects on human carbonic anhydrase I and II (hCA I and II), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-glycosidase, and α-amylase enzymes, as well as its antiproliferative effects on A-549 lung cancer, HT-29 colon cancer, MCF-7 and MDA-MB-453 breast cancer cell lines, and the 3T3-L1 mouse fibroblast normal cell line, were investigated. To determine the antioxidant capacity of Shogaol, DPPH and ABTS radical scavenging assays, as well as Cu²⁺, Fe³⁺, and FRAP reduction methods, were employed. Its inhibitory effects on hCA I and II, AChE, BChE, α-glycosidase, and α-amylase enzymes were examined. Furthermore, cell counting was performed using the TBE method, and cell viability was measured with the XTT assay to assess the antiproliferative effects of Shogaol on A-549, HT-29, MCF-7, MDA-MB-453, and 3T3-L1 cell lines. Shogaol demonstrated higher antioxidant capacity than BHA, BHT, and Trolox in the FRAP assay (60 µg/mL), higher than BHT in the DPPH scavenging assay, and higher than Trolox in the ABTS, Cu²⁺, and Fe³⁺ reduction assays. Shogaol also exhibited significant inhibitory effects against hCA I, hCA II, AChE, BChE, and α-glycosidase, with IC₅₀ values of 75.91, 47.04, 37.44, 24.11, and 35.72 nM, respectively. Moreover, Shogaol showed a more potent antiproliferative effect than the standard chemotherapeutic drug Carboplatin in A-549 lung cancer and HT-29 colon cancer cell lines, and greater efficacy than Docetaxel in the MCF-7 breast cancer cell line.
AtıfOpenAlex1İncele - MakaleYalnız künye2020Scopus SJRQ1Optimization of ultrafast laser parameters for 3D micromachining of fused silica
Dogan, Yusuf; Madsen, Christi K.
We present an optimization study on laser parameters for 3D micromachining of fused silica to achieve critical goals for practical applications including high surface quality, high volume production, and complex surfaces by ultrafast laser direct writing assisted chemical etching. We conducted experiments on laser pulse width of 300 fs and 1 ps, pulse energy ranging from 0.1 µJ to 1.6 µJ, three different polarizations (circular, parallel and perpendicular) and number of overlapped pulses from 3 to 10,000 at 1030 nm with up to 2 MHz repetition rate to investigate their effect on nanogratings and one dimensional (1D) channel and two dimensional (2D) planar surface selective etching on 1 mm thick fused silica. In one configuration, we achieved 21.8 nm RMS surface roughness with 80 µm Gaussian filtering and in another configuration, we estimated the maximum writing speed to be 1.25 m/s for given 2 MHz repetition rate with less than 400 nm filtered root mean square (RMS) surface roughness at a 1 mm2 area which covers the thickness of the glass.
AtıfScopus21WoS17OpenAlex23İncele - MakaleAçık Erişim2021The Impact of Recreational Use on Land Cover at Uludağ National Park (Turkey)
Uzun, Serir; Çakır, Günay; Yıldız, Oktay; Aksoy, Necmi; Sargıncı, Murat; Toprak, Bülent; Müderrisoğlu, Haldun
The intense pressure resulting from population growth and urbanization along with technology has created the need for utilizing natural areas for tourism and recreational purposes and has necessitated the protection, development, and planning of natural resources for people to benefit from. Due to the importance of determining temporal changes within the framework of the protection-use balance, this study examined the changes occurring within the recreational areas of the Uludağ National Park between the years 1970 and 2010 from human use. As a result of the recreational facilities offered to visitors, an average of 550 000 people benefits annually from the area, which was designated as a national park in 1961. The study included the camping and picnic sites of Sarıalan, Çobankaya, Kirazlıyayla, and Karabelen situated within the park and the ski site of the first development zone. High-resolution satellite images and aerial photographs of the areas at different dates were employed. The temporal changes in the selected areas were analyzed by digital image processing with the help of the geographic information system. Upon examining the impact of the recreational use changes occurring on the land cover, it was revealed that building areas had increased by 15 ha (2.57%), road areas by 21 ha (7.89%), and bare land areas by 67 ha (.53%), while the meadowland areas had decreased by 223 ha (119.37%). The forested areas had increased by 78 ha (48.93%), woodland areas by 79 ha (59.37%) and were not adversely affected, mainly due to the protection status of the park.
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İncele - MakaleYalnız künye2021Scopus SJRQ2Investigation of characterization and tribological behavior of composite oxide coatings doped with h-BN and graphite particles on ZA-27 alloy by micro-arc oxidation
Kaplan, Erdar; Sukuroglu, Ebru Emine; Cuvalci, Olkan
This paper investigates the tribological effects of composite oxide coatings grown on ZA-27 surfaces under dry sliding condition. Coating processes were conducted using three different electrolytic solutions through micro-arc oxidation (MAO) method. The base electrolytic solution without any particles as additives was labeled as MAO-Coated, whereas electrolytic solution labeled as Coated-A contained graphite particles and Coated-B contained hexagonal boron nitride (h-BN) particles incorporated into base solution. The morphology of each coated samples were analyzed using a Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD). The friction and wear tests were conducted using a pin-on-disc tester in order to evaluate the tribological behavior. Results indicated the friction coefficients of both Coated-A and Coated-B samples were lower when compared to that of uncoated ZA-27 alloy. Further comparative studies showed Coated-A samples containing graphite particles resulted in the lowest friction coefficient.
AtıfScopus13WoS12OpenAlex14İncele - MakaleYalnız künye2020Scopus SJRQ2A review study on using diethyl ether in diesel engines: Effects on fuel properties, injection, and combustion characteristics
Sezer, İsmet
This study was compiled from the results of various researches performed on using diethyl ether as a fuel or fuel additive in diesel engines. Three different techniques are used, the reduction of the harmful exhaust emissions of diesel engines. The first technique for the reduction of harmful emissions has improved the combustion by modification of engine design and fuel injection system, but this process is expensive and time-consuming. The second technique is the use of various exhaust gas devices like catalytic converter and diesel particulate filter. However, the use of these devices affects negatively diesel engine performance. The final technique to reduce emissions and also improve diesel engine performance is the use of various alternative fuels or fuel additives. The major pollutants of diesel engines are nitrogen oxides and particulate matter. It is very difficult to reduce nitrogen oxides and particulate matter emissions simultaneously in practice. Most researches declare that the best way to reduce these emissions is the use of various alternative fuels i.e. natural gas, biogas, biodiesel, or the use of fuel additives with these alternative fuels or conventional diesel fuel. Therefore, it is very important that the results of various studies on alternative fuels or fuel additives are evaluated together for practice applications. Especially, this study focuses on the use of diethyl ether in diesel engines as fuel or fuel additive in various diesel engine fuels. This review study investigates the effects of diethyl ether on the fuel properties, injection, and combustion characteristics.
AtıfScopus55WoS42OpenAlex61İncele - Kitap BölümüYalnız künye2020Basic instruments in European Union urbanization policy
Cengiz, Emre
- MakaleYalnız künye2014Scopus SJRQ1Simultaneous separation and preconcentration of Ni(II) and Cu(II) ions by coprecipitation without any carrier element in some food and water samples
Duran, Celal; Tumay, Sureyya O.; Ozdes, Duygu; Serencam, Huseyin; Bektas, Hakan
A simple and highly sensitive separation and preconcentration procedure, which has minimal impact on the environment, has been developed. The procedure is based on the carrier element-free coprecipitation of Ni(II) and Cu(II) ions by using 2-{4-[2-(1H-Indol-3-yl)ethyl]-3-(4-chlorobenzyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl}-N′-(pyrrol-2-ylmethyliden)acetohydrazide (ICOTPA), as an organic coprecipitant. The levels of analyte ions were determined by flame atomic absorption spectrometry. The detection limits for Ni(II) and Cu(II) ions were found to be 0.27 and 0.58 μg L-1, respectively, and the relative standard deviations for the analyte ions were lower than 4.0%. Spike tests and certified reference material analyses were performed to validate the method. The method was successfully applied for the determination of Ni(II) and Cu(II) ions levels in sea and stream water as liquid samples and red lentil and rice as solid samples.
AtıfScopus26WoS23OpenAlex25İncele - MakaleYalnız künye2010Scopus SJRQ1Sources and petrogenesis of Jurassic granitoids in the Yusufeli area, Northeastern Turkey: Implications for pre- and post-collisional lithospheric thinning of the eastern Pontides
Dokuz, Abdurrahman; Karsli, Orhan; Chen, Bin; Uysal, Ibrahim
Small granitoids emplaced into the early Jurassic volcani-clastic succession in the Yusufeli area, northeastern Turkey, can be temporally and geochemically classified into two groups: early Jurassic low-K and late Jurassic high-K. 40Ar-39Ar hornblende analyses yielded 188.0 ± 4.3 Ma for the Dutlupi{dotless}nar intrusion, dating the subduction related rifting in the region. It comprises metaluminous to weakly peraluminous (ASI = 0.94-1.11) granodiorite and, to a lesser extent, tonalite whose K2O-poor (< 2.04 wt.%) nature and weak negative Eu anomalies (Eu/Eu* = 0.9-0.7) preclude derivation by fractional crystallization from a K-rich melt. Sr, Nd and Pb isotopic data reveal derivation by partial melting from an already cooled tholeiitic basic rocks which had mantle-like isotope signature. The Sumbated intrusion formed in the late Jurassic (153.0 ± 3.4 Ma) and consists chiefly of metaluminous (ASI = 0.84-0.99) quartz monzodiorite. Medium to high-K2O, relatively high MgO and Sr contents, flat HREE patterns without prominent Eu anomalies, slightly positive εNd(t) values (+ 1.5 to + 2.5) and low ISr ratios (0.7046-0.7056) are consistent with an origin by dehydration melting of a juvenile source, above the garnet stability field, dominated by likely K-amphibole bearing calc-alkaline mafic rocks. Geochemical data show that fractional crystallization from a Sumbated-like quartz monzodioritic magma is the fundamental process responsible for the evolved compositional range of the Keçikaya intrusion. The geochemical and geochronological data presented here indicate that the late Jurassic magmatism occurred in a post-collisional setting. Slab-breakoff, which was followed by shortly after collision, seems to be the most plausible mechanism for the generation of medium to high-K calc-alkaline rocks of the Sumbated and the Keçikaya intrusions, indicating a switch in the geodynamic setting, e.g., from pre-collision to post-collision in the middle Jurassic in the eastern Pontides.
AtıfScopus123OpenAlex122İncele - MakaleYalnız künye2011Scopus SJRQ1Determination of seasonal changes in olive oil by using differential scanning calorimetry heating thermograms
Ilyasoglu, Huri; Ozcelik, Beraat
Thermal properties (upon heating) of extra virgin olive oils (EVOOs) from Aegean cultivars were determined to evaluate the possibility of using differential scanning calorimetry (DSC) as a tool for monitoring seasonal changes in chemical composition. Chemical properties of the samples were analyzed to assess the relationship between the thermal properties and chemical properties as well. The thermal properties of Aegean cultivars were found to be influenced by major components (palmitic acid, oleic acid, linoleic acid, triolein and palmitodiolein). The melting offset temperature, the temperature range of melting and the melting enthalpy of Aegean cultivars presented significant differences with respect to crop season (p < 0.05). DSC may be utilized to evaluate compositional changes with respect to crop season.
AtıfScopus8WoS7OpenAlex7İncele - MakaleYalnız künye2014Scopus SJRQ1Geochemical fingerprints of Late Triassic calc-alkaline lamprophyres from the Eastern Pontides, NE Turkey: A key to understanding lamprophyre formation in a subduction-related environment
Karsli, Orhan; Dokuz, Abdurrahman; Kaliwoda, Melanie; Uysal, Ibrahim; Aydin, Faruk; Kandemir, Raif; Fehr, Karl-Thomas
The Eastern Pontides in NE Turkey is one of the major orogenic belts in Anatolia. In this paper, we report our new 40Ar/39Ar dating, mineral chemistry, major and trace elements and Sr-Nd-Pb isotopic analyses of the lamprophyre intrusions in this region. The lamprophyres are widely scattered and intrude Late Carboniferous granitoid rocks. The lamprophyres exhibit fine-grained textures and are mineralogically uniform. Hornblende 40Ar/39Ar dating yielded a plateau age of 216.01±10.64Ma. Based on their geochemistry, mineral compositions and paragenesis, the lamprophyres are classified as calc-alkaline lamprophyres in general and spessartites in particular, which are rich in large ion lithophile elements (e.g., Rb, Ba, K) but depleted in Nb and Ti. Our samples exhibit moderate fractionation in LREE patterns approximately 100 times that of chondrite but HREE abundances less than 10 times that of chondrite. These calc-alkaline lamprophyres display a range of ISr (216Ma) values from 0.70619 to 0.71291 and εNd (216Ma) values from -1.4 to 4.1, with TDM=1.11 to 2.20Ga. Their Pb isotopic ratios indicate an enriched mantle source. The enrichment process is related to metasomatism of a subcontinental lithospheric mantle source, which is caused by a large quantity of H2O-rich fluids, rather than sediments released from oceanic crust at depth during the closure of the Paleotethys Ocean in Triassic times. All of the geochemical data and the trace element modeling suggest that the primary magma of the calc-alkaline to high-K calc-alkaline spessartites was generated at depth by a low degree of partial melting (~1-10%) of a previously enriched lithospheric mantle wedge consisting of phlogopite-bearing spinel peridotite. The ascendance of a hot asthenosphere triggered by extensional events caused partial melting of mantle material. The rising melts were accompanied by fractional crystallization and crustal contamination en route to the surface. All of the geochemical features combined with regional data suggest that the Eastern Pontides calc-alkaline lamprophyres originated in an extensional environment along an active continental margin throughout the Late Triassic. Such an extensional event, causing upwelling of hot asthenosphere, led to the opening of the northern branch of the Neotethys as a back-arc basin farther south of the Eastern Pontides.
AtıfScopus81WoS79OpenAlex89İncele - MakaleAçık Erişim2013Scopus SJRQ3Spaces of continuous and bounded functions over the field of geometric complex numbers
Cakir, Zafer
Following Grossman and Katz (Non-Newtonian Calculus, 1972), we construct the sets B(A) and C(A) of geometric complex-valued bounded and continuous functions, where A denotes the compact subset of the complex plane C. We show that the sets B(A) and C(A) of complex-valued bounded and continuous functions form a vector space with respect to the addition and scalar multiplication in the sense of multiplicative calculus. Finally, we prove that B(A) and C(A) are complete metric spaces.
AtıfScopus10WoS5OpenAlex9İncele - MakaleYalnız künye2011Scopus SJRQ1Petrochemistry and U-Pb zircon ages of adakitic intrusions from the pulur massif (eastern pontides, ne Turkey): Implications for slab rollback and ridge subduction associated with Cenozoic convergent tectonics in the eastern Mediterranean
Eyuboglu, Yener; Santosh, M.; Chung, Sun-Lin
The well-preserved magmatic arc in the eastern Pontides orogenic belt of northeastern Turkey offers critical clues on convergent margin tectonics associated with the late Mesozoic-early Cenozoic geodynamic evolution of the eastern Mediterranean region. Here we investigate the petrology, geochemistry, and U-Pb zircon chronology of adakitic intrusions from the Pulur region in the southern zone of the eastern Pontides belt. The intermediate to felsic intrusives in the Pulur region are characterized by the presence of abundant plagioclase, amphibole, and biotite phenocrysts. The rocks display extreme light rare earth element enrichment (LaN YbN p13.69-51.08); high Al2O3 (15.46-17.47 N Nwt%), Na2O (3.57-8.43 wt%), Sr (324.8-1468 ppm), and La (13.9-55.8 ppm) concentrations; a high Sr/Y ratio (35-473); and low Y (3-12.6 ppm) and heavy rare earth element concentrations, closely comparing with the typical features of adakites. Zircons extracted from the Pulur adakites show euhedral crystal shapes, oscillatory zoning patterns, andhigh Th/U ratios (up to 3.33) consistent with their magmatic origin. Their 206Pb/238U ages show a range of 55.21-53.07 Ma, correlating the magmatism to the early Eocene. We propose a tectonic model involving the initiation of a slab rollback and simultaneous opening of a slab window during ridge subduction in a south-dipping sub duction zone for the origin of the Tertiary adakitic and nonadakitic magmatism in the eastern Pontides orogenic belt. We also identify a close relation between slab rollback processes and back arc extension, which led to the opening of the Tertiary basins in the southern part of the eastern Pontide orogenic belt. The eastern Pontide orogenic belt is one of the world's largest metallogenic provinces, and it hosts various economic mine ralizations such as volcanogenic massive sulfide, epithermal gold-silver, porphyry copper-molybdenum, skarn-type, and chromite. However, the adakitic intrusions exposed in the southern part of the eastern Pontide orogenic belt are devoid of ore deposits, which leads us to propose that the Lutetian or later nonadakitic granitic intrusions exposed at the north of the Gumushane-Bayburt-Ispir line were probably responsible for the epithermal gold mineralization in this belt.
AtıfScopus51WoS49OpenAlex51İncele - MakaleYalnız künye2014Scopus SJRQ4Origin of analcimes in the Tertiary volcanic rocks from the Eastern Pontides (NE Turkey): A textural, mineralogical and geochemical approach
Yücel, Cem; Temizel, Irfan; Abdioʇlu, Emel; Arslan, Mehmet; Yaʇcioʇlu, Ufuk Celal
Silica-undersaturated mafic volcanic rocks of Tertiary age in form of lava flows, dikes and sills of tephritic compositions extend along the northern part of the Eastern Pontides. These rocks typically contain Ca-clinopyroxene (Wo32-53En26-54Fs8-24), analcime, Fe-Ti oxides, apatite and minor olivine, plagioclase (An49 - 94), K-feldspar (Or29 - 66), hornblende and phlogopite in microgranular porphyritic, hyalo-microlitic porphyritic and glomeroporphyritic textures. Petrochemical features of the studied rocks, such as enrichment in LILE, depletion in Nb, Ta and Ti and moderate or high LREE/HREE ratios, provide strong evidence for melt production from a subduction-metasomatized lithospheric mantle. Besides, the rocks are characterized by their low K2O contents and low K2O/Na2O ratios as a result of analcimization. Analcime detected in these rocks appears to have formed by pseudomorphic mineral replacement reactions. Euhedral or anhedral analcime crystals, 100 - 600 um in diameter, are set in groundmass and display six-sided polygon or rounded shape and irregular cracks. The analcime pseudomorphs are colourless, milky white to grey and occur in clinopyroxene or in the groundmass. Based on the electron microprobe results, analcimes contain a minor amount of cations other than Na and probably represent the remnants of leucite as marked by K-zoning. X-ray diffraction studies of the analcime-bearing samples confirm the presence of cubic and tetragonal analcime crystals in addition to tetragonal leucite. The presence of Ca-clinopyroxene and plagioclase rather than their sodic equivalents, presence of anhydrous mineral phases and lack of Na differentiation trend as well as partial alteration of the rocks likely supports the secondary growth of analcime either during cooling or after magma solidification.
AtıfScopus16WoS17OpenAlex17İncele - MakaleYalnız künye2012Scopus SJRQ2Aflatoxin levels in raw and processed hazelnuts in Turkey
Baltaci, C.; Ilyasoǧlu, H.; Cavrar, S.
Aflatoxin levels in hazelnut samples obtained from exporter companies were monitored over a 3-year period. A total of 3188 samples of raw and processed hazelnuts were analysed using an HPLC method. The total aflatoxin content of the contaminated samples was in the range of 0.02-78.98 μg kg-1 for hazelnut kernels, 0.07-43.59 μg kg-1 for roasted hazelnut kernels, 0.02-39.17 μg kg-1 for roasted sliced hazelnut kernels, and 0.02-11.20 μg kg-1 for hazelnut purees, respectively, showing that the variations of aflatoxin contamination were very high. The results of aflatoxin analysis revealed that the aflatoxin contamination in the hazelnut samples was at a tolerable level. A total of 3147 samples were contaminated with aflatoxins, although below the legal limits. However, the aflatoxin contents of 41 samples exceeded the legal limits. Therefore, aflatoxin contents of hazelnuts should be monitored regularly to minimise the risk of aflatoxin hazard, and pre- and post-harvest strategies should be developed to prevent aflatoxin formation.
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İncele - MakaleYalnız künye2014Scopus SJRQ3New desmid records of Karagöl Lake in Karagöl-Sahara National Park (Şavşat-Artvin/Turkey); [Karagöl-Sahara Milli Parki{dotless}'ndaki (Şavşat-Artvin/Türkiye) karagöl'den yeni desmid kayi{dotless}tlari{dotless}]
Akar, Bülent; Şahin, Bülent
The benthic algal flora of Karagöl Lake (Şavşat, Artvin) was investigated between October 2008 and September 2010. Actinotaenium diplosporum var. americanum, Cosmarium pseudoexiguum, Gonatozygon kinahanii, Staurastrum boreale var. quadriradiatum, S. hantzschii and Staurodesmus dejectus var. apiculatus were recorded for the first time for the desmid flora of Turkey.
AtıfScopus13WoS12OpenAlex2İncele - MakaleAçık Erişim2015Scopus SJRQ2Preparation and characterization of electroless Ni-B/nano-SiO2, Al2O3, TiO2 and CuO composite coatings
Ekmekci, Dursun; Bülbül, Ferhat
Ni-B/SiO2, Al2O3, TiO2 and CuO composite coatings were successfully obtained by the electroless plating technique. Dispersible SiO2, Al2O3, TiO2 and CuO nanoparticles were co-deposited with electroless Ni-B coating onto AISI-304 steel substrates. Deposits were characterized for its structural properties by X-ray diffraction (XRD). XRD results showed a broad peak of Ni-B and low intensity composite nanoparticle peaks. The surface and cross-section morphology of samples were analysed using a scanning electron microscope (SEM). Surface analysis showed that the incorporation in Ni-B matrix of nano-SiO2, Al2O3, TiO2 and CuO particles increases the nodularity of composite coatings. The deposits are composed of a columnar structure grown along the vertical direction of the substrate surface. The results also show that electroless nanocomposite coatings tend to have greater microhardness compared with the coating without nanoparticles. The increase in the microhardness of the nanocomposite coatings reported in this study is attributed to an effect of dispersion strengthening of ceramic particles in the Ni-B matrix.
AtıfScopus51WoS46OpenAlex59İncele - BildiriAçık Erişim2010Assessment of Turkish and class teacher candidate's attitudes towards children's literature and children's literature lesson
Ulaş, A. Halim; Kolaç, Emine; Topal, Yakup; Sevim, Oǧuzhan
Purpose of this research is to reveal class and Turkish teacher candidates' attitudes towards children's literature lesson, and works of children's literature. Study group of this research is comprised of students from Classroom Teaching and Turkish Teaching Departments of Faculty of Education of Atatürk University. Answers were sought for the level of classroom teaching and preschool teacher candidates' towards children's literature lesson, and works of children's literature, and whether there is any significant difference is seen in classroom teaching and pre-school teacher candidates' towards children's literature lesson, and works of children's literature in terms gender, and departments. Having the research conducted according to survey method (2007), "Attitude Scale towards Children's Literature, and Children's Literature Lesson", having been developed by ..., and comprised of 35 articles, was made use of. At the end of the research, it was concluded that teacher candidates had developed a positive attitude towards children's literature, and children's literature lesson, and neither gender, nor field differences had significantly affected that attitude.
AtıfOpenAlex1İncele - MakaleYalnız künye2015Scopus SJRQ3Magnetic Relaxation in a Y 0.5Lu0.5Ba2Cu3O y Superconductor at Various Magnetization Levels
Çelebi, S.; Ozturk, A.; Uysal, E.; Kutuk, S.; Duzgun, I.
The evolution of the rate of flux creep along the major hysteresis envelopes in a Y0.5Lu0.5Ba2Ca3Oy sample synthesized by a modified melt powder melt growth (MPMG) method at 25 K has been investigated. Magnetic relaxation rates depend strongly on the prior magnetic history. Calculations based on the critical state model can reproduce quite well the experimental data for magnetization when we have chosen the field exponent n = 0.3 in critical current density, Jc(Ha) = Jc0/(Ha−IM)n, where IM = Ha when 0 < H < Hc1 and (Formula presented.) when Ha ≥ Hc1. Using the field-cooled magnetization MFC data as well as the comparison of experimental and calculated M–H hysteresis loop, we estimated Hc1 = 500 Oe, p = 0, and the penetration field H∗ = 20 kOe. The apparent pinning energy was estimated as 62 meV for the remanent magnetization upon an excursion of 40 kOe.
- MakaleYalnız künye2015Scopus SJRQ4An integrated evaluation model for service quality of hospitals: A case study from Turkey
Baki, Birdogan; Peker, Iskender
In this paper, an integrated approach, in which Fuzzy Analytic Hierarchy Process (FAHP) and Fuzzy TOPSIS (FTOPSIS) is used, is proposed to rank the hospitals according to service quality from the patient's point of view. The FAHP is employed to determine the weights of service quality criteria for the hospitals, and FTOPSIS method is used to rank the hospitals. Empirical results show that when "reliability" is the most important criterion, "empathy" is the least important criterion in terms of hospital service quality. A sensitivity analysis is also applied to check how sensitive our model is to changes in the various criteria weights.
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