Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Uzun, Sevda(87)
- Merdan, Mehmet(70)
- Duran, Celal(56)
- Baltaci, Cemalettin(52)
- Kulakaç, Nurşen(51)
- Ozdes, Duygu(51)
- Kaygusuz, Abdullah(47)
- Öztürk, Serkan(42)
- Demir, Selim(40)
- Karsli, Orhan(37)
- Turan, Ibrahim(37)
- Dokuz, Abdurrahman(36)
- Gücer, Mehmet Ali(36)
- Sipahi, Ferkan(36)
- Araz, Onur(35)
- Kandemir, Raif(31)
- Vural, Alaaddin(31)
- Topal, Fevzi(30)
- Kurt, Kemal(29)
- Ürkek, Bayram(29)
- Maden, Nafiz(28)
- Acet, Tuba(27)
- Alemdag, Selcuk(26)
- Arslan, Mehmet(26)
- Ayaydin, Hasan(26)
- Akaryali, Enver(25)
- Aydin, Faruk(25)
- Baltacı, Cemalettin(25)
- Yücel, Cem(25)
- Akar, Zeynep(24)
- Barut, Abdulkadir(24)
- Ozturk, Samet(24)
- Pala, Fahrettin(24)
- Peker, Iskender(24)
- Topal, Meryem(24)
- Yildiz, Salih(24)
- Öz, Mehmet(24)
- Aliyazicioglu, Yuksel(23)
- Bostan, Sedat(23)
- Kankal, Murat(23)
Yayınlar
- MakaleYalnız künye2017Scopus SJRQ2Evaluation of potentially toxic element contents and Pb isotopic compositions in Ankara Stream sediments within an urban catchment in central Turkey
Eker, Çiğdem Saydam; Sipahi, Ferkan; Özkan, Özay; Gümüş, Mustafa Kemal
This study aimed to interpret the spatial distribution, enrichment factor (EF), and geo-accumulation of potentially toxic elements in the bed sediments (ASBS) and Pleistocene-aged overbank sediments (ASOS) of the Ankara Stream in Turkey. The potential toxic pollution of the investigated potentially toxic elements was defined by evaluating the EF, geo-accumulation index (Igeo), and Pb anthropogenic contribution. The distributions of As, Ni, and Co in the analyzed sediments were uniform in the ASBS and ASOS along the length of the stream. The EF and Igeo values indicated that ASBS and ASOS were significantly polluted by As and Ni and moderately polluted by Co, Zn, and Cu. ASBS was locally strongly polluted by Pb and Cd. Pb anthropogenic contribution was estimated at an average of > 100% in the ASBS and ASOS. The potentially toxic element levels and distribution patterns revealed that industrial activities, gasoline combustion, vehicular emission, phosphate fertilizers and natural sources were probable causes of metal pollution in Ankara Stream sediments. These potentially toxic elements were transported by atmospheric conditions and stream water. The potentially toxic elements in Ankara Stream increased with each passing day and were important in evaluating the potential toxicity risks to living organisms. Thus, suitable measures should be taken to ensure appropriate treatment of wastewater before toxic residues are disposed into the nearby stream. Chimney filter, treatment plants, and appropriate technology should be used in the organized industrial zone to prevent atmospheric pollution.
AtıfScopus12WoS10OpenAlex12
İncele - MakaleYalnız künye2017Scopus SJRQ2Isolation and Characterization of Thermophilic Bacteria from Geothermal Areas in Turkey and Preliminary Research on Biotechnologically Important Enzyme Production
Baltaci, Mustafa Ozkan; Genc, Berna; Arslan, Sumeyya; Adiguzel, Gulsah; Adiguzel, Ahmet
In this study, the isolation, identification and characterization of the thermophilic bacteria from different hot springs in Turkey were carried out by conventional (morphological, physiological and biochemical tests) and molecular methods (fatty acid methyl esters, GTG5-PCR and 16S rRNA sequencing). These thermophilic bacteria were then tested for their capability to produce enzymes such as lipase, protease, amylase and cellulase. O20 strain is a novel species according to identification studies. All of its isolates were capable of producing industrially valuable enzymes based on screening. In fact, most of them could produce at least two of these enzymes.
AtıfScopus64WoS46OpenAlex71İncele - MakaleAçık Erişim2017Scopus SJRQ3Influence of Duplex Treatment on Structural and Tribological Properties of Commercially Pure Titanium
Çelik, Ilhan
Titanium and its alloys are widely used in many fields, including aerospace and the chemical and biomedical industries. This is due to their mechanical properties, excellent corrosion resistance, and biocompatibility although they do have poor wear resistance. In this study, a duplex layer was successfully formed on the commercially pure titanium surface by duplex treatments (plasma nitriding and physical vapor deposition (PVD)). In the initial treatment, plasma nitriding was performed on the pure titanium samples and in the second treatment, the nitrided samples were coated with CrN by PVD. The friction and wear properties of the duplex-treated samples were investigated for tribological applications. Surface morphology and microstructure of the duplex-treated samples were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). In addition, the tribological properties were investigated using pin-on-disc tribometer. A compound layer composed of ϵ-Ti2N and δ-TiN phases and a diffusion layer formed under the compound layer were obtained on the surface of pure titanium after the nitriding treatments. CrN coated on the nitrided surface provided an increase in the surface hardness and in the wear resistance.
AtıfScopus4WoS4İncele - MakaleYalnız künye2017Scopus SJRQ4Molecular docking analysis and determination of minimum inhibition concentration of VIM-38/R228S
Duzgun, Azer Ozad; Saral, Aysegul
Objective: The aim of this study was to determine the effects of residues at 228th positions of VIM-38 on minimum inhibition concentration (MIC) and molecular docking analysis. Materials and methods: blaVIM-38 gene was cloned into expression vector pET100/D-TOPO. Then pET100/D-TOPO-VIM-38 was used to generate the R228S mutation by site-directed mutagenesis. The mutant was transformed into E. coli Dh5α. Changes in the activity of mutation R228S was determined by E-test. Molecular docking analysis of the binding affinity of meropenem and imipenem with VIM-38 and VIM-38 R228S was performed using AutoDock Vina_1_1_2. Results: According to E-test results, pET100/D-TOPO-VIM-38 and pET100/D-TOPO-VIM-38/ R228S have same MIC value for amoxicillin, ticarcillin/clavulanic acid, ampicillin and ticarcillin. It was determined decrease in pET100/D-TOPO-VIM-38/ R228S of MIC for aztreonam, amikacin and cefixine. There are 3-fold deference in MIC between pET100/D-TOPO-VIM-38 and pET100/D-TOPO-VIM-38/ R228S for cefoxitin. pET100/D-TOPO-VIM-38 has 0.5 µg/ml and pET100/D-TOPO-VIM-38/ R228S has 0.125 µg/m for imipenem, we observed 4-fold deference. Also, there is about 170-fold deference between pET100/D-TOPO-VIM-38 (16 µg/ml) and pET100/D-TOPO-VIM-38/ R228S (0.094 µg/ml) for meropenem. VIM-38 and VIM-38 R228S have very close to the negative low free energies of binding of the meropenem and imipenem. Conclusion: These results showed that substitution (R228S) slightly have effect on enzyme activity.
- MakaleAçık Erişim2017Scopus SJRQ1Analysis of transcriptional profiles of Saccharomyces cerevisiae exposed to bisphenol A
Bereketoglu, Ceyhun; Arga, Kazim Yalcin; Eraslan, Serpil; Mertoglu, Bulent
Bisphenol A (BPA), an endocrine disrupting chemical, is used as a monomer in the production of epoxy resins and polycarbonates, and as a plasticizer in polyvinyl chloride. As such, it is produced in large quantities worldwide and continuously leaches into the environment. To capture the genome reprogramming in eukaryotic cells under BPA exposure, here, we used Saccharomyces cerevisiae as model organism and analyzed the genome-wide transcriptional profiles of S. cerevisiae BY4742 in response to BPA, focusing on two exposure scenarios: (1) exposure to a low inhibition concentration (50 mg/L; resulting in <10 % inhibition in cell number) and (2) a high inhibition concentration (300 mg/L; resulting in >70 % inhibition in cell number). Based on the transcriptional profiling analyses, 81 genes were repressed and 104 genes were induced in response to 50 mg/L BPA. Meanwhile, 378 genes were downregulated and 606 genes were significantly upregulated upon exposure to 300 mg/L BPA. While similar processes were affected by exposure to distinct BPA concentrations, including mitochondrial processes, nucleobase-containing small molecule metabolic processes, transcription from the RNA polymerase II promoter, and mitosis and associated processes, the number and magnitude of differentially expressed genes differ between low and high inhibition concentration treatments. For example, exposure to 300 mg/L BPA resulted in severe changes in the expression levels of several genes involved in oxidative phosphorylation, the tricarboxylic acid cycle, ribosomal activity, replication, and chemical responses. Conversely, only slight changes were observed in the expression of genes involved in these processes in cells exposed to 50 mg/L BPA. These results demonstrate that yeast cells respond to BPA in a concentration-dependent manner at the transcriptional level via different genes and provide insight into the molecular mechanisms underlying the modes of action of BPA.
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İncele - MakaleAçık Erişim2017Scopus SJRQ1Rice bran improve probiotic viability in yoghurt and provide added antioxidative benefits
Demirci, Talha; Aktaş, Kübra; Sözeri, Didem; Öztürk, Hale İnci; Akın, Nihat
Experimental yoghurts were made with 13% reconstituted skim milk supplemented with 1, 2, 3% rice bran (RB) and inoculated with probiotic culture of Lactobacillus casei 431. The products were stored at 4 °C for 3 weeks. During this period, the viability of the probiotic L. casei 431 strain and yoghurt starter cultures were evaluated. In addition to this, some physicochemical, antioxidative and sensory properties of yoghurts were also determined. L. casei 431 remained above the 8 log CFU/g throughout the storage period in yoghurts fortified with 2% and 3% RB. Addition of rice bran decreased the syneresis and viscosity values whereas it increased scavenging activities of DPPH radical. However, yoghurts with RB had less sensory scores compared to plain yoghurt.
AtıfScopus115WoS91İncele - MakaleYalnız künye2017Scopus SJRQ2The effect of TiO2 coating on biological NiTi alloys after micro-arc oxidation treatment for corrosion resistance
Sukuroglu, Ebru Emine; Sukuroglu, Suleyman; Akar, Kubra; Totik, Yasar; Efeoglu, Ihsan; Arslan, Ersin
NiTi alloys exhibit good properties, such as shape memory behavior, high corrosion resistant, having the closest elasticity modulus of a human bone and superior biocompatibility properties. However, the surface problems that arise during the use of this alloy limit the usage in the industry and health sector. In recent years, micro-arc oxidation method is used to improve the surface properties and increase the usage of these alloys. In this study, the TiO2 coatings were deposited on the NiTi substrates. The surface topography, morphology, crystallographic structure, and thickness of the coatings were determined using scanning electron microscopy and X-ray diffraction. The corrosion properties were investigated using potentiostat test unit in two different media such as NaCl solution and simulated body fluid. The results show that the coated samples have higher corrosion resistance than uncoated samples in the two different media.
AtıfScopus10WoS11OpenAlex11İncele - MakaleAçık Erişim2017Scopus SJRQ2Sexual health literacy as a predictor of reproductive health and family planning attitudes among university students: a cross-sectional study
Karaahmet, Aysu Yıldız; Bilgiç, Fatma Şule; Karakaş, Sevda
Introduction: This study was conducted to investigate the relationship between sexual health literacy (SHL) and reproductive health and family planning (RHFP) attitudes among university students and to identify the sociodemographic and informational predictors influencing these variables. Methods: A descriptive, cross-sectional design was employed with a sample of 867 university students aged 18-35 in Türkiye between May and September 2024. Data were collected using a Sociodemographic Questionnaire, the Sexual Health Literacy Scale (SHLS), and the Reproductive Health and Family Planning Attitude Scale (RHFPAS). Data analysis included Pearson correlation and multiple linear regression models to determine predictors and relationships. Results: The findings revealed a strong positive correlation between SHL and RHFP attitudes (r = 0.880, P < .05). Multiple linear regression analysis showed that total SHLS scores and students’ conceptual definitions of sexual health were significant predictors of RHFP attitudes. In particular, the knowledge and attitude subscales of the SHLS were identified as key determinants. Furthermore, residence type, sexual activity status, and information sources were found to significantly influence both SHL levels and RHFP attitudes. Discussion: SHL is a critical determinant in shaping the RHFP attitudes of young adults. Higher literacy levels directly correlate with more positive attitudes toward reproductive health services, suggesting that targeted educational interventions are necessary to improve health outcomes in this population.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2017Scopus SJRQ1Environmental impact of Gümüşhane City, Turkey, waste area in terms of heavy metal pollution
Vural, Alaaddin; Gundogdu, Ali; Akpinar, Ibrahim; Baltaci, Cemalettin
The aim of this study is to investigate the occurrence of a heavy metal contamination in a solid waste site of Gümüşhane City, Turkey, to examine the dimensions of the risk of contamination, and to present suggestions for possible solutions. For this purpose, heavy metal contents of soil and leachate samples taken from a Gümüşhane waste site were determined by a new method, microwave plasma-atomic emission spectrometry (MP-AES). When the obtained results are compared with background and control values, it can be seen that the region carries contamination risks, especially in terms of heavy metals such as Zn, Cd, Pb, Cu, Ni, and Co. To examine the environmental effects of the landfill area in more detail, geodeposition index (Igeo), enrichment factor (EF), contamination index (PI), and combined contamination index (IPI) parameters are used. In addition, the samples taken from an area supposed to be free of pollution risk were also analyzed as control samples, and the obtained data were statistically compared with the results of the waste area. It is determined that the results of landfill waste site are dissimilar to those of comparison samples in terms of investigated metals, and that they contained higher values in general.
AtıfScopus19WoS16OpenAlex21İncele - MakaleAçık Erişim2017Scopus SJRQ2Bounds for the radii of univalence of some special functions
Aktaş, Ibrahim; Baricz, Árpád; Yaǧmur, Nihat
Tight lower and upper bounds for the radii of univalence (and starlikeness) of some normalized Bessel, Struve and Lommel functions of the first kind are obtained via Euler-Rayleigh inequalities. It is shown also that the radius of univalence of the Struve functions is greater than the corresponding radius of univalence of Bessel functions. Moreover, by using the idea of Kreyszig and Todd, and Wilf it is proved that the radii of univalence of some normalized Struve and Lommel functions are exactly the radii of starlikeness of the same functions, and they are actually solutions of some functional equations. The Laguerre-Pólya class of entire functions plays an important role in our study.
AtıfScopus35WoS34OpenAlex22İncele - MakaleYalnız künye2017Scopus SJRQ2Series tuned mass dampers in train-induced vibration control of railway bridges
Kahya, Volkan; Araz, Onur
This paper presents the series multiple tuned mass dampers (STMDs) to suppress the resonant vibrations of railway bridges under the passage of high-speed trains (HSTs). A STMD device consisting of two spring-mass-damper units connected each other in series is installed on the bridge. In solution, bridge is modeled as a simply-supported Euler-Bernoulli beam with constant cross-section, and vehicle is simulated as a series of moving forces with constant speed. By the assumed mode method, the governing equations of motion of the beam-TMD device coupled system traversed by a moving train are obtained. The optimum values for the parameters of the STMD device are obtained for the criterion based on the minimization of the maximum dynamic displacement of the beam at its midspan. Single TMD and multiple TMDs in parallel are also considered for demonstration of the STMD device's performance. The results show that STMDs are effective in bridge vibration suppression and robust to parameters' change in the main system and the absorber itself.
AtıfScopus27WoS24İncele - MakaleYalnız künye2017Scopus SJRQ1Exploring collaboration in learning by design via weblogs
Çakiroğlu, Ünal; Yildiz, Merve; Mazlum, Ebru; Turan Güntepe, Ebru; Aydin, Şenay
The purpose of this qualitative study was to explore collaborative activities that were carried out via weblogs according to a “learning by design” approach. During the instructional process, Microsoft Publisher was used for a series of infographic design activities. The study participants were 33 undergraduate students who were enrolled in an Arts Education program. The data sources included weblogs that were used by the participants to discuss the design process, as well as reflection reports that they provided. The data were analyzed according to Murphy’s collaboration model, which involved associating the participants’ experiences in the design process with the sub-phases of collaboration outlined in the model. The results indicated that, through the use of weblogs, the participants were able to design infographics via a “learning by design” approach. The weblogs allowed students to share their knowledge, and thereby to develop better artifacts. It is hoped that the study may provide insights concerning the link between weblogs and the learning by design approach in graphic design activities.
AtıfScopus8WoS6OpenAlex10İncele - MakaleYalnız künye2017Scopus SJRQ1Combustion properties of impregnated spruce (Picea orientalis L.) wood
Şadiye Yasar, Ş.; Said Fidan, M.; Yaşar, Mehmet; Atar, Musa; Alkan, Elif
Wooden material is one of the most commonly used construction materials since history of humanity due to its environment friendly and renewable natural source. This structure of wood material is also preferred because it is lightweight, easy to work, resistant to factors such as earthquake and fire, as compared to other used building materials. However, organic structure of the wooden material causes it to be affected negatively because of damages that might occur outdoors under inappropriate conditions. Due to this reason, in this study were investigated effects of various chemicals (impregnated and varnish type), used to prevent environmental damages (biotic, abiotic pests, fire etc.) on combustion resistance of the wood exposed to air conditions for a year. For this purpose, prepared Caucasian spruce (Picea orientalis L.) specimens were surface treated (synthetic and water-based varnish) after impregnated according to ASTM-D 1413-76 principles with various chemicals (Tanalith-E and Wolmanit-CB). Test specimens with impregnated, varnished and processless, were left in outdoor conditions for a year. Combustion experiment was conducted according to the principles in ASTM-E 160-50 combustion test standards. According to the results of the experiment, control and year specimens had close results in the weight loss. Weight loss was found be lower Wolmanit-CB impregnated specimens (92.12%) among the impregnated materials to synthetic varnish coated specimens (% 91.89) among the varnished specimens. It was determined that using Wolmanit-CB for impregnating and synthetic varnish for varnishing would be better according to the results. Furthermore, the amount of O2 (25.84 ppm) in control specimens in combustion with flame; the amounts of CO and CO2 (31787, 19.92 ppm respectively) in year specimens in combustion without flame and the amount of NO (54.65 ppm) in year specimens in glowing was observed to be the highest.
AtıfScopus4WoS8OpenAlex8İncele - MakaleYalnız künye2017Scopus SJRQ2Effect of powder of macaroni boiling water (by-product) on textural, oil uptake, physico-chemical, sensory and morphological properties of fried wheat chips
Yuksel, Ferhat
The current study was conducted with the purpose to produce wheat chips enriched with powder of pasta boiling water (PPBW). Pasting properties of chips dough changed with addition of powder of pasta boiling water. The textural properties of dough samples decreased with the addition of PPBW, but there were no differences between 2nd and 3rd samples including 10 and 20 % PPBW. The oil content of the samples decreased with the increase of PPBW from 33.78 to 22.19 %. The morphological analysis showed that the number of pores and pore size decreased with the addition of PPBW. Maximum overall acceptability score of the samples was given for control samples (5.64) while the overall acceptability of samples with 10 % PPBW was close to control sample (5.14). PPBW may be used in the formulation of chips it may be used to be coating matter for snacks in food industry.
AtıfScopus7WoS5OpenAlex9İncele - MakaleAçık Erişim2017Scopus SJRQ2Bounds for Radii of Starlikeness of Some q -Bessel Functions
Aktaş, İbrahim; Baricz, Árpád
In this paper the radii of starlikeness of Jackson’s second and third q-Bessel functions are considered and for each of them three different normalization are applied. By applying Euler–Rayleigh inequalities for the first positive zeros of these functions tight lower and upper bounds for the radii of starlikeness of these functions are obtained. The Laguerre–Pólya class of real entire functions plays an important role in this study. In particular, we obtain some new bounds for the first positive zero of the derivative of the classical Bessel function of the first kind.
AtıfScopus38WoS38OpenAlex38İncele - MakaleAçık Erişim2017Scopus SJRQ1Evolution of K-rich magmas derived from a net veined lithospheric mantle in an ongoing extensional setting: Geochronology and geochemistry of Eocene and Miocene volcanic rocks from Eastern Pontides (Turkey)
Yücel, Cem; Arslan, Mehmet; Temizel, İrfan; Abdioğlu Yazar, Emel; Ruffet, Gilles
The Eocene and Miocene volcanic rocks between the cities of Trabzon and Giresun in the Eastern Pontides (NE Turkey) erupted as mildly and moderately alkaline magmas ranging from silica-saturated to silica-undersaturated types. 40Ar-39Ar dating and petrochemical data reveal that the studied volcanic rocks are discriminated in two: Lutetian (Middle Eocene) mildly alkaline, (basaltic rocks: 45.31 ± 0.18 to 43.86 ± 0.19 Ma; trachytic rocks: 44.87 ± 0.22 to 41.32 ± 0.12 Ma), and Messinian (Late Miocene) moderately alkaline volcanic rocks (tephrytic rocks: 6.05 ± 0.06 and 5.65 ± 0.06 Ma). The trace and the rare earth element systematic, characterised by moderate light earth element (LREE)/heavy rare earth element (HREE) ratios in the Eocene basaltic and trachytic rocks, high LREE/HREE ratios in the Miocene tephrytic rocks, and different degrees of depletion in Nb, Ta, Ti coupled with high Th/Yb ratios, show that the parental magmas of the volcanic rocks were derived from mantle sources previously enriched by slab-derived fluids and subducted sediments. The Sr, Nd and Pb isotopic composition of the Eocene and Miocene volcanic rocks support the presence of subduction-modified subcontinental lithospheric mantle. During the magma ascent in the crust, parental magmas of both the Eocene and Miocene volcanic rocks were mostly affected by fractional crystallisation rather than assimilation coupled with fractional crystallisation and mixing. The silica-undersaturated character of the Miocene tephrytic rocks could be attributed to assimilation of carbonate rocks within shallow-level magma chambers. The parental magmas of the Eocene volcanic rocks resulted from a relatively high melting degree of a net veined mantle and surrounding peridotites in the spinel stability field due to an increase in temperature, resulting from asthenospheric upwelling related to the extension of lithosphere subsequent to delamination. The parental magmas for the Miocene volcanic rocks resulted from a relatively low melting degree of a net veined mantle domain previously modified by metasomatic melts derived from a garnet peridotite source after decompression due to extensional tectonics, combined with strike-slip movement at a regional scale related to ongoing delamination.
AtıfScopus77WoS74OpenAlex86İncele - MakaleYayıncıda açık erişim2017Scopus SJRQ2Analysis of the changes in forest ecosystem functions, structure and composition in the Black Sea region of Turkey
Keleş, Sedat; Durusoy, İdris; Çakir, Günay
We used geographical information system to analyze changes in forest ecosystem functions, structure and composition in a typical department of forest management area consisting of four forest management planning units in Turkey. To assess these effects over a 25 year period we compiled data from three forest management plans that were made in 1986, 2001 and 2011. Temporal changes in forest ecosystem functions were estimated based on the three pillars of forest sustainability: economics, ecology and socio-culture. We assessed a few indicators such as land-use and forest cover, forest types, tree species, development stage, stand age classes, crown closure, growing stock and its increment, and timber biomass. The results of the case study suggested a shift in forest values away from economic values toward ecological and socio-cultural values over last two planning periods. Forest ecosystem structure improved, due mainly to increasing forest area, decreasing non-forest areas (especially in settlement and agricultural areas), forestation on forest openings, rehabilitation of degraded forests, conversion of even-aged forests to uneven-aged forests and conversion of coppice forests to high forests with greater growing stock increments. There were also favorable changes in forest management planning approaches.
AtıfScopus16WoS18OpenAlex21İncele - MakaleAçık Erişim2017Scopus SJRQ1Long term outdoor performances of three different on-grid PV arrays in central Anatolia – An extended analysis
Ozden, Talat; Akinoglu, Bulent G.; Turan, Rasit
Long term outdoor testing of the PV systems at different climatic conditions or different systems under the same ambient conditions are extremely important in producing policies for the transition to renewables. The present research is the testing of three different PV systems under the same climatic conditions of central Anatolia, after four years of operation. The systems consist of a mono-Si, an a-Si thin film and a CdTe thin film arrays. Different calculation procedures of the input solar irradiation on tilted surface are used for comparison. Performances together with degradation rates are computed using different procedures and also using the measured solar data of 20 km away from the installed systems. The accuracy is verified using 4 months of simultaneous measurements. The results showed that the aforementioned different input calculation procedures of the performances are important and determinant. The 44-months-average efficiencies of these three systems are calculated to be 11.86%, 6.40% and 5.30%, respectively. The degradation rates of these systems are obtained as 0.40%, 1.88% and 10.60%, respectively. Although the degradation rates that are calculated for the first two systems are quite similar to those appeared in the literature, CdTe system is considerably higher than those given in the literature.
AtıfScopus77WoS63OpenAlex76İncele - MakaleAçık Erişim2017Scopus SJRQ3The importance of amount of settlement in determining the bearing capacity of soils
Alemdaǧ, Selçuk; Cinoǧlu, Aslihan; Gacener, Elif
In this study, it is aimed to determine safe bearing capacity of soils, which are out cropped around Tamzi and Akcakale villages located in Gumushane, providing allowable settlement conditions for an optimum foundation design. To define the geotechnical properties of soils, three trenches were dug and two seismic refraction with two Multichannel Spectral Analysis of Surface Waves (MASW) were carried out in each research area. Sieve analyses, shear box tests, triaxial compression tests were carried out on disturbed and undisturbed samples taken from the trenches. Seismic velocities of the soils are determined by seismic refraction and MASW methods. While determining the safe bearing capacity; the equations proposed by Terzaghi, Meyerhof, Kurtuluş, Tezcan and Özdemir, Türker, Keçeli were used and the obtained safe bearing capacity values were compared to each other. After, the soils were modeled numerically by using finite elements method and safe bearing capacities providing allowable settlement conditions were determined. According to the results, safe bearing capacity values obtained from empirical equations are not satisfactory to have an optimum foundation design. For the optimum foundation design, safe bearing capacity should be accepted as 190 kN/m2 for clayey soil (CL) and 485 kN/m2 for the clayey sand (SC).
AtıfScopus1OpenAlex4İncele - MakaleYalnız künye2017Scopus SJRQ3In situ gamma ray measurements for deciphering of radioactivity level in Sarıhan pluton area of northeastern Turkey
Çınar, Hakan; Altundaş, Suna; Çelik, Necati; Maden, Nafız
The present work utilizes in situ gamma ray spectrometric measurement data to map the surface geology of Sarıhan Granitoid and its surrounding area. The study area comprises three different lithological units, namely, Hozbirikyayla Formation (limestone and sandy limestones), Sarıhan Granitoid (consist of quartz monzodiorite, granodiorite and quartz diorite) and the Ophiolitic olistostromal melange (andesite, basalt, sandstone, gravelly sandstone). When lithological units are assessed according to the radioactivity characteristics, natural radionuclide contents (40K and radionuclides from 238U and 232Th series) of Hozbirikyayla limestones and ophiolitic melange rocks are lower than the Sarıhan pluton. The U, Th and K radionuclide contents were found to be 0.8–5.4 ppm, 10.1–33.6 ppm and 1.29–4.41% in the Sarıhan plutonic area and 0.9–5.3 ppm, 1.1–20.3 ppm and 0.04–2.71% in Horzbirikyayla formation, respectively. The element concentrations of 238U, 232Th and 40K of the Ophiolitic melange are 1.1–4.5 ppm, 1.6–25.3 ppm and 0.09–3.63%, respectively. Radioelement ratio maps are created for the studied area, because the parameters of radioelement ratios, eU/eTh, eU/K and eTh/K, reflect the radioactive characters of the rock and soil. The Hozbirikyayla Formation is characterized by the highest value of eU/eTh and lowest value of eTh/K. While the lowest eU/eTh and eU/K ratios were observed in the Sarıhan Granodiorite, the highest value of eU/K and eTh/K were obtained in the Ophiolitic olistostromal melange. By comparing these maps with the geology, it was found that the radioelement concentrations are in good agreement with the geological properties of the region. In addition to this, the radiation hazard parameters were evaluated to assess the radiation hazard for people living in this area. It has also been found that there is no significant radiologic hazard for humans and the environment in and around studied area.
AtıfScopus13WoS14OpenAlex18İncele