Koleksiyon/r/gumushane/10001

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Koleksiyondaki öğeler

  • BildiriYalnız künye2013
    The effect of integration types on FLC based MPPT systems

    Cakmak, Recep; Altas, Ismail H.

    Operating the photovoltaic (PV) array at its maximum power available is important to increase system efficiency. In order to operate PV systems at their maximum power point, many maximum power point tracking (MPPT) methods have been proposed. Fuzzy logic controller (FLC) based MPPT methods have some advantages over classical MPPT methods. The way of using the FLC outputs has an effective role in obtaining the desired results. In this study, the effect of a discrete-time integration method investigated in MPPT including FLC whose output is subjected to integration operation. The system has been designed and simulated in MATLAB/Simulink software. The results were given as a comparison.

    • SDG 7 · Erişilebilir ve Temiz Enerji
    AtıfScopus1OpenAlex1
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  • MakaleYalnız künye2013Scopus SJRQ3
    Determination of the pomological and morphological properties of white mulberry types growing in transition region between mild and continental climates

    Kalkişim, Özgün

    This study was performed in 2010 and 2011 in order to determine some pomological and morphological properties of 15 different mulberry types growing in the ecological conditions of Gümüşhane province. From chosen types, fruit and leaf samples were collected and analyzed during their growing season for the period of two years. By the end of the study, the following highest values were observed: fruit weight 27.30 g, fruit width (resp. height) 15.62 mm (resp. 30.32 mm), leaf width (resp. height) 100.84 mm (resp. 130.02 mm), leaf stalk length 50.94 mm, Brix 23.28%, pH 6.20, titratable acidity 0.20, invert sugar 20.57, sucrose 1.46 and total sugar 22.02 g/100 g. As a result of the study, knowing the fact that mulberry is an important raw material in the continuously growing dried fruit roll-up industry, it is concluded that the number of promising mulberry types with the finest properties, should be increased and their cultivation should be popularized.

    AtıfScopus3WoS3
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  • BildiriYalnız künye2013
    Genetic algorithm in Electrical Transmission Lines path finding problems

    Eroglu, Hasan; Aydin, Musa

    Today, Geographic Information Systems (GIS) solutions have entered every corner of the engineering studies like Electrical Transmission Lines (ETL) route optimization, vehicle routing, power plant siting and so on. Raster-based maps generated by GIS are very useful solutions for this kind of route optimization problems. The weighted sum of all the data can be converted to raster-based maps and gathered consecutively in GIS for ETL route optimization. In this paper, Genetic Algorithm (GA) is applied to ETL route optimization problems in order to find the best route on raster-based maps.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfScopus12WoS7OpenAlex13
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  • MakaleYalnız künye2012Scopus SJRQ1
    Soil geochemical prospection for gold deposit in the Arzular area (NE Turkey)

    Yaylali-Abanuz, Gülten; Tüysüz, Necati; Akaryali, Enver

    The Arzular gold mineralization is located at the southern part of the Black Sea Tectonic Unit in northern Turkey. This belt hosts several high-potential epithermal gold deposits and it is highly probable that there are a number of undiscovered occurrences in the region. The presence of intensely altered areas, suitable structural elements and acidic intrusions indicates that the region has an important potential for epithermal gold. Soil geochemistry surveys are widely used for the exploration of buried mineral deposits. In this work the applicability of soil geochemistry surveys for exploration of buried mineral deposits was tested using various statistical methods. In this respect, concentrations of 16 elements have been assayed in about 50 soil samples collected from the Arzular area. Soil samples were taken from the B horizon. The data revealed elevated concentrations for gold (0.20-259.2 μg/kg), silver (23-26,972 μg/kg), arsenic (1.7-301.8. mg/kg), copper (54.09-170.7. mg/kg), zinc (5.1-261.3. mg/kg) and lead (2.6-385.45. mg/kg). Gold is significantly correlated with elements such as Sb, Cd, Pb, Ag, As, Cu and Mo. Relatively high anomaly contrasts between Au, As, Ag and Sb and their coinciding anomalies along an E-W trending fault at the eastern part of the field might indicate that As, Ag and Sb could be used as a pathfinder element for exploration of gold deposits. Factor analysis was applied to elements in soil samples and then distribution diagrams were prepared using the factor scores obtained. In a distribution diagram for mineralization-associated factor score, two anomaly fields along the E-W trending fracture line and one anomaly field at the eastern part were distinguished. The largest anomaly in an ellipsoidal shape with long axis of 350. m was obtained from the southeast part of the area. Anomaly patterns show that factor scores might yield suitable and net results for the exploration. NE-SW trending fracture system is not related to mineralization and is younger than E-W trending fracture line. However, the E-W trending fault system controls the mineralization; therefore, the eastern extent of this fault zone needs to be investigated.

    AtıfScopus19WoS16OpenAlex20
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  • MakaleYalnız künye2012Scopus SJRQ2
    Numerical solution of time-fraction modified equal width wave equation

    Merdan, Mehmet; Yildirim, Ahmet; Gökdoǧan, Ahmet

    Purpose - The purpose of this paper is to show how an application of fractional two dimensional differential transformation method (DTM) obtained approximate analytical solution of time-fraction modified equal width wave (MEW) equation. Design/methodology/approach - The fractional derivative is described in the Caputo sense. Findings - It is indicated that the solutions obtained by the two dimensional DTM are reliable and that this is an effective method for strongly nonlinear partial equations. Originality/value - The paper shows that exact solutions can also be obtained from the known forms of the series solutions.

    AtıfScopus10WoS10OpenAlex15
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  • MakaleYalnız künye2014Scopus SJRQ1
    Attitudes Toward Ethically Questionable Negotiation Tactics: A Two-Country Study

    Banai, Moshe; Stefanidis, Abraham; Shetach, Ana; Özbek, Mehmet Ferhat

    Current research has identified five discrete US negotiation tactics, a traditional one considered to be ethical, and four considered to be ethically questionable. Scholars have independently used culture to explain how the endorsement of these five negotiation tactics varies across nations. They have also independently used interpersonal trust and ethics propensity to explain antecedents of the endorsement of those five negotiation tactics. This research combines all those variables into one model that investigates the influence of horizontal and vertical individualism–collectivism, ethical idealism, and trust propensity on employees’ attitudes toward ethically questionable negotiation tactics in Israel and Kyrgyzstan. A survey questionnaire was translated from English to Hebrew and Kyrgyz, and 615 responses were collected from employees in various industries in the two countries. We empirically confirmed three types of questionable negotiation tactics discovered in previous one-nation studies, namely, pretending, deceiving, and lying. Vertical individualism was found to be positively, and horizontal collectivism was found to be negatively, related to pretending, deceiving, and lying. Ethical idealism was found to be negatively related to the endorsement of the lying tactics, while trust propensity was negatively related to the pretending tactics. Compared with Israel, employees’ endorsement of ethically questionable negotiation tactics was significantly higher in Kyrgyzstan. Contribution to theory and practice is discussed.

    • SDG 16 · Barış, Adalet ve Güçlü Kurumlar
    AtıfScopus21WoS18OpenAlex23
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  • MakaleYayıncıda açık erişim2014Scopus SJRQ3
    Effect of rootstock on grafted grapevine quality

    Köse, B.; Karabulut, B.; Ceylan, K.

    As the home of numerous grape genotypes, Turkey is one of the major centers of viniculture genetic material in the world. 'Merzifon Karasi' (Vitis vinifera L.) is one of the most valuable red wine grape cultivars in Turkey. However, despite the variety's relative age, 'Merzifon Karasi' has yet to be tested on different rootstocks. Therefore, this study was conducted to determine the effects of different rootstocks on the growth characteristics of 'Merzifon Karasi' scion. Growth parameters (shoot length (cm), shoot diameter (mm), internode length (cm), total and unit leaf area (cm2), root length (cm), root scale (0-4) and root number) were calculated and carbohydrate content (%) of the grafted grapevine shoots, trunk and roots analysed for 9 different rootstocks. Significant differences (P < 0.01) were found among rootstocks. 8B and Rupestris du Lot rated best in terms of root length, root scale and root number (P < 0.01). Highest shoot length, shoot diameter (P < 0.01) and internode length were obtained, respectively, with the 110R, 8B and Rupestris du Lot rootstocks (P < 0.05). Rupestris du Lot also produced the grapevines with the highest total leaf area per plant and main shoot, whereas the grapevines grafted on 8B had the highest unit leaf area (P < 0.01). Sugar, starch and carbohydrate contents (%) of the different plant parts also varied significantly by rootstock (P < 0.01), with the highest root carbohydrate content measured in the 5C (22.4 %) rootstock, and the highest trunk and shoot carbohydrate content measured in the 110R (12.1 and 13.4 %, respectively). In sum, the study found the best rootstocks for 'Merzifon Karasi' to be 8B, Rupestris du Lot and 110R in terms of root and shoot growth, whereas 'Merzifon Karasi' grape grafted onto 110R and 5C rootstock had the highest carbohydrate contents.

    AtıfScopus23WoS24
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  • Derleme MakaleYalnız künye2015Scopus SJRQ1
    Seismic b-Values, Bouguer Gravity and Heat Flow Data Beneath Eastern Anatolia, Turkey: Tectonic Implications

    Maden, Nafiz; Öztürk, Serkan

    In this paper, we analyze the relationships between the seismic b-values, Bouguer gravity and heat flow data in the Eastern Anatolia region of Turkey. For this purpose, spatial distributions of b-value, Bouguer gravity and heat flow have been presented for different depths and locations. In distinction to previous studies which have used only two parameters (gravity and seismic b-value or heat flow and seismic b-value), we have combined seismic b-values, Bouguer gravity and heat flow data to determine the new results on the active tectonics of the Eastern Anatolia region. Our analysis shows that there are significant and robust correlations amidst the heat flow data, Bouguer gravity anomaly and seismic b-values. The crustal structure is thick in areas where the large negative gravity anomalies and low b-values are observed. On the contrary, the regions with positive gravity anomalies and high b-values are likely to be associated with magma chambers or crustal low-velocity zones. We also provide some evidence suggesting that high b-values and high heat flow values can be related to the magmatic activities beneath the volcanic chain in the Eastern Pontide orogenic belt. Consequently, we have reached some conclusions for the Eastern Anatolia region: (1) The Moho to surface is rather thick and earthquakes are relatively smaller beneath the volcanic chain where the high heat flow values are observed, (2) a southward subduction model could have existed for the development of the Pontides during the late Mesozoic–Cenozoic era, (3) hot and unstable mantle lid zones or a lithosphere deprived of mantle under the study region is much more plausible, (4) a southward movement of the subduction plate and a northward extension of the Black Sea increase the state of stress along the trench axis and decrease the b-value, and (5) these movements may load the stress energy to the fault zones, thereby causing the catastrophic earthquakes in the Eastern Anatolia region.

    AtıfScopus45WoS40OpenAlex47
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  • MakaleAçık Erişim2012Scopus SJRQ3
    Synthesis and antimicrobial activity of new phthalocyanine complexes and electrochemical and spectroelectrochemical behaviour of cobaltphthalocyanine

    Kaya, Elif Çelenk; Karadeniz, Hülya; Koca, Atif; Kahriman, Nuran; Sökmen, Atalay

    A novel phthalocyanine bearing oxygen donor atoms on the peripheral positions has been synthesised by cyclotetramerisation of (E)-4-(4- cinnamoylphenoxy) phthalonitrile and its nickel, zinc, cobalt, copper and lead derivatives prepared. The thermal stabilities of the phthalocyanine compounds have been determined and their possible biological activities (antibacterial, anticandidal and antifungal) studied. The effects of substituent on the electrochemical and in situ spectroelectrochemical behaviour of cobaltphthalocyanine have been investigated and an in situ electrocolorimetric method was applied to investigate the colour of the electrogenerated anionic and cationic forms of the complex.

    AtıfScopus5WoS4OpenAlex4
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  • MakaleYalnız künye2014Scopus SJRQ1
    Prediction of wave parameters by using fuzzy inference system and the parametric models along the south coasts of the Black Sea

    Akpinar, Adem; Özger, Mehmet; Kömürcü, Murat Ihsan

    Forecasting of sea-state characteristics has a great importance in coastal and ocean engineering studies. Therefore, the purpose of this study was to investigate performances of Adaptive-Network-Based Fuzzy Inference System (ANFIS) and several parametric methods in the Black Sea. For this purpose, different fuzzy models with different input combinations were developed for two different wind data sources (TSMS and ECMWF) at two offshore buoy stations. It also aimed to apply several approaches to event-based data sets for wave predictions. Generally, in literature the tendency is to use time series data for wave predictions. In this kind of prediction approach, lagged time series data are taken as inputs and current or future variables are taken as output. In this study, event-based data for each independent storm were extracted from time series data. Simultaneous or concurrent data of wind speed, blowing duration, fetch length and wave characteristics were detected for each single storm. These event data were then used to set up models. The hindcast results were validated with significant wave height and mean wave period data recorded in Hopa and Sinop buoy stations. The performance of developed fuzzy models were also compared with that of four different parametric methods (Wilson, SPM, Jonswap, and CEM methods) applied for two wind data sources at both buoy stations. Finally, it was determined that in the prediction of both wave parameters (H s and T z) the ANFIS models (R = 0.66, squared correlation coefficient, and MAE = 0.37 m, mean absolute error, for the best model in prediction of H s) were more accurate than the parametric methods (R = 0.63 and MAE = 0.75 m for the best model in prediction of H s).

    AtıfScopus31WoS27OpenAlex30
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  • MakaleYalnız künye2010Scopus SJRQ2
    Comparison of stepped and smooth spillway effects on stream reaeration

    Aras, Egemen; Berkun, Mehmet

    The oxygen transfer at a hydraulic structure happens by self-aeration through the spillway and by flow aeration in the hydraulic jump downstream of the hydraulic structure. Spillways with their water-air controlling mechanisms are important not only for their structural properties but also for their effects on stream ecology. Spillway types also affect the efficiency of aeration. Decisions on the types of spillway should be made by taking the environmental conditions and flow rates into consideration. This paper compares the aeration efficiency of stepped and smooth spillways. Empirical correlations predicting length of the non-aerated flow region and aeration efficiency are developed. Smooth and stepped spillways cause increased dissolved oxygen (DO) concentrations at the downstream part of the channel. DO concentration changes are shown to depend on the flow types, discharge rates, tail-water depth and travelling times.

    AtıfScopus22WoS14
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  • MakaleYayıncıda açık erişim2011Scopus SJRQ3
    Analysis of support requirements for a tunnel portal in weak rock: A case study from Turkey

    Kaya, Ayberk; Bulut, Fikri; Alemdaǧ, Selçuk; Sayin, Aytuna

    In this paper, engineering geological properties of the entrance portal section of Konakönü Tunnel, located on Black Sea Coastal Highway, Turkey, is studied. Moderately weathered basaltic and andesitic tuffs orderly to be driven by the entrance portal section. Tunnel portal design in weak rock presents some special challenges to the designers, since misjudgements in the design of tunnel can lead to very costly failures. The entrance portal was analyzed by empirical and numerical methods. Both field and laboratory studies were carried out during this study. Field studies involved geological mapping, detailed discontinuity surveying and sampling. Laboratory tests were carried out to determine the physico-mechanical and elastical properties of rock units. For this purpose, tunnel stability analyses were performed at the entrance portal section. The RMR (rock mass rating), Q (rock mass quality), RMi (rock mass index), NATM (new Austrian tunnelling method) and GSI (geological strength index) systems were employed for empirical rock mass quality determination and preliminary tunnel portal support design. The parameters calculated by the empirical methods were used as input parameters for the FEM (finite element method) analysis. The results from the two methods were compared and preliminary support designs were carried out. This comparison suggests that for more reliable support design, empirical and finite element methods should be combined.

    AtıfScopus32OpenAlex33
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  • MakaleYalnız künye2012Scopus SJRQ3
    Phytochemical and antioxidant characteristics of medlar fruits (Mespilus germanica L.)

    Ercisli, S.; Sengul, M.; Yildiz, H.; Sener, D.; Duralija, B.; Voca, S.; Dujmovic Purgar, D.

    Eleven medlar {Mespilus germanica L.) genotypes sampled from Turkey were analyzed for their fruit weight, fruit dimensions, fruit firmness, ostiole diameter, shape index, skin color, moisture (%), ash (%), reducing sugar (%), crude protein (%), pH, soluble solid content (%), vitamin C (mg/100 g), minerals (P, K, Ca, Mg, Fe, Zn, Mn), total phenolic content and total antioxidant capacity. A wide variation among genotypes on most of the searched parameters was evident. Fruit weight varied from 11.21 g to 33.24 g indicating high variability among genotypes. Determination of antioxidant activities by β-carotene - linoleic acid and 2-diphenyl-l-picrylhydrazyl (DPPH) free radical scavenging assays resulted in average 80.8%, and 46.6 μg/ml FW DPPH, respectively. The total phenolic contents of eleven medlar genotypes varied from 114 to 293 mg gallic acid equivalent in 100 g fresh weight basis. The medlar fruits were found to be rich in terms of potassium, calcium, phosphorus, magnesium and iron.

    AtıfScopus28WoS29
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  • MakaleYalnız künye2011Scopus SJRQ2
    The effect of fin pitch on heat transfer and fluid flow characteristics in the entrance region of a finned concentric passage

    Kuvvet, Kemal; Yavuz, Tahir

    In this study, the heat transfer and fluid flow characteristics in the unfinned and internally finned concentric passage (smooth and finned annulus) are investigated experimentally. The turbulence characteristics, mean flow, pressure drop and heat-transfer parameters in the entrance region of a concentric passage of diameter ratio 0.2 are measured. The hot-wire anemometer and the liquid-crystal technique are used for the turbulence and mean flow and the heat transfer measurements, respectively. The finned passage is designed as the fin width (W) of 2 mm, the fin height (H) of 2, 4, 6 and 8 mm and the fin pitch (P) of 20, 30 and 40 mm. Reynolds number ranges from 1.8 .104 to 1.24.105 and from 1.65.104 to 7.65.104 for flow and pressure drop and heat transfer measurements, respectively. Experiments are performed for the smooth and finned concentric passages by varying flow and fin parameters and the effects of the fin pitch are investigated. The developing of fluid flow is analyzed and the variation of turbulence intensity, friction factors, local and mean convective heat transfer coefficients in the smooth and finned concentric passages are obtained. Results obtained in the finned concentric passages are compared with the results of the smooth passage. For the average Nusselt numbers and friction factor, empirical equations are developed. As a result, it is seen that the friction factor in the finned passage increases between 3.61 and 18.05 times while the average Nusselt number augments between 1.36 and 5.23 times on the inner surface and between 1.03 and 1.80 times on the outer surface.

    AtıfScopus4WoS4TR Dizin1
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  • BildiriYalnız künye2013
    Revisiting graphical passwords for augmenting, not replacing, text passwords

    Akpulat, Murat; Bicakci, Kemal; Cil, Ugur

    Users generally choose weak passwords which can be easily guessed. On the other hand, adoption of alternatives to text passwords has been slow due to cost and usability factors. We acknowledge that incumbent passwords remain difficult to beat and introduce in this study Type&Click (T&C), a hybrid scheme supporting text passwords with the graphical passwords. In T&C, users first type a text as usual and then make a single click on an image to complete the password entry. While largely preserving the login experience with the text passwords, the new scheme utilizes accumulated scientific knowledge in graphical password research (implicit feedback, persuasion during password creation, leveraging cued recall memory). The results of our user study suggest that T&C is promising for augmenting text passwords for improved security without degrading usability. Copyright 2013 ACM.

    AtıfScopus3OpenAlex4
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  • MakaleYalnız künye2010Scopus SJRQ1
    Stochastic finite element analysis of a cable-stayed bridge system with varying material properties

    Çavdar, Özlem; Bayraktar, Alemdar; Adanur, Süleyman

    Stochastic seismic finite element analysis of a cable-stayed bridge whose material properties are described by random fields is presented in this paper. The stochastic perturbation technique and Monte Carlo simulation (MCS) method are used in the analyses. A summary of MCS and perturbation based stochastic finite element dynamic analysis formulation of structural system is given. The Jindo Bridge, constructed in South Korea, is chosen as a numerical example. The Kocaeli earthquake in 1999 is considered as a ground motion. During the stochastic analysis, displacements and internal forces of the considered bridge are obtained from perturbation based stochastic finite element method (SFEM) and MCS method by changing elastic modulus and mass density as random variable. The efficiency and accuracy of the proposed SFEM algorithm are evaluated by comparison with results of MCS method. The results imply that perturbation based SFEM method gives close results to MCS method and it can be used instead of MCS method, especially, if computational cost is taken into consideration.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfScopus17WoS13OpenAlex20
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  • BildiriAçık Erişim2018
    OBJECT BASED BUILDING EXTRACTION and BUILDING PERIOD ESTIMATION from UNMANNED AERIAL VEHICLE DATA

    Comert, Resul; Kaplan, Onur

    The aim of this study is to examine whether it is possible to estimate the building periods with respect to the building heights in the urban scale seismic performance assessment studies by using the building height retrieved from the unmanned aerial vehicle (UAV) data. For this purpose, a small area, which includes eight residential reinforced concrete buildings, was selected in Eskisehir (Turkey) city center. In this paper, the possibilities of obtaining the building heights that are used in the estimation of building periods from UAV based data, have been investigated. The investigations were carried out in 3 stages; (i) Building boundary extraction with Object Based Image Analysis (OBIA), (ii) height calculation for buildings of interest from nDSM and accuracy assessment with the terrestrial survey. (iii) Estimation of building period using height information. The average difference between the periods estimated according to the heights obtained from field measurements and from the UAV data is 2.86 % and the maximum difference is 13.2 %. Results of this study have shown that the building heights retrieved from the UAV data can be used in the building period estimation in the urban scale vulnerability assessments.

    • SDG 11 · Sürdürülebilir Şehirler ve Topluluklar
    AtıfScopus9OpenAlex10
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  • MakaleAçık Erişim2019Scopus SJRQ1
    Petrology and 40Ar-39Ar dating of paragneisses from the Devrekani Massif (Central Pontides, Northern Turkey): Implications for the Jurassic high-T metamorphism in an extensional tectonic environment

    Gücer, Mehmet Ali; Arslan, Mehmet; Çimen, Okay; Sherlock, Sarah C.

    The Devrekani Massif in the northern part of the Central Pontides (Northern Turkey) provides important clues to the regional tectonics and geodynamic processes associated with Jurassic high grade metamorphic conditions. This study reports new paragenetic assemblages, mineral compositions, whole-rock geochemistry and 40Ar-39Ar geochronological data from the paragneisses in the massif, and, discusses the P–T conditions and geodynamic implications of the Jurassic metamorphism during continental extension in the Central Pontides. Upper amphibolite to lower granulite facies paragneisses form one of the main lithological units in the massif. Within these, there are five different mineral parageneses with diagnostic mineral assemblages of: quartz, K-feldspar (An0-1Ab4-26Or73-96), plagioclase (An18-35), biotite [XPhl: 0.28–0.57; Mg/(Mg + Fe2+): 0.33–0.61], sillimanite, cordierite [Mg/(Mg + Fe2+): 0.48–0.71] and garnet (Alm43-80Grs0-18Prp5-23And0-4Sps10-33) with minor hercynite. Based on Na-in-Crd thermometry and GASP barometry results, the peak metamorphic conditions are 775 ± 25 °C and 6 ± 1 kbar in the massif. The field relations, petrography and bulk chemical data suggest that the paragneisses, derived from shale-wackestone and pelitic sedimentary protoliths, are typical rock lithologies of an active continental margin. They display enrichments in LILE over HFSE, coupled with negative Nb and Ti anomalies, which are geochemical signatures of subduction-related sources. It is likely that the peak metamorphism took place during the Middle–Upper Jurassic period (ca. 174–156 Ma), suggesting that the metamorphic rocks cooled to 300–350 °C at ca. 156 Ma. The mineral assemblages reveal that the prograde history passed from sillimanite zone conditions up to the cordierite-garnet-K-feldspar zone. The petrological and geochronological data indicate that the protoliths are related to multiple sources such as volcano-sedimentary successions. We conclude that the Devrekani Massif represents the products of pre-Jurassic sedimentation, and Permo-Carboniferous continental arc magmatism, overprinted by Jurassic metamorphism.

    AtıfScopus9WoS10OpenAlex6
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  • MakaleAçık Erişim2016Scopus SJRQ2
    Use of polyvinyl chloride (PVC) powder and granules as aggregate replacement in concrete mixtures

    Bolat, Hakan; Erkus, Pinar

    Concrete is one of the materials in which polymer wastes are utilized. Generally, these wastes are added at specific rates in scientific studies but an important problem of waste polymers is size irregularity. Even when consistent dosage rates are used, variations in polymer size can lead to variability in the physical and mechanical properties of the concrete produced. The aim of this study is to determine physical and mechanical properties of polyvinyl chloride (PVC)-containing concretes. In order to produce normal and high strength concretes, 10%, 20%, and 30% replacement ratios of PVC powder and granules by volume of aggregate are used. Slump, fresh and hardened densities, compressive strength, capillary water absorption, and abrasion were tested on all concrete types. As the PVC ratio increases, important changes are seen in all physical and mechanical concrete properties. The unit weights of the 10%, 20%, and 30% replacement PVC powder concretes are lower by ∼4%, 8%, and 13%, respectively, as compared to the reference mixtures, and the replacement PVC granule concretes are lower by ∼2%, 4%, and 7%. Compressive strength test results showed similar trends. As PVC replacement increases, the capillary water absorption decreases between 10% and 50%, and abrasion decreases between 27% and 77%.

    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus41WoS33OpenAlex48
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  • MakaleYalnız künye2016Scopus SJRQ2
    Investigation of the quality and physical-geochemical characteristics of the drinking water in Gümüşhane (Turkey) city central

    Sipahi, Ferkan; Uslu, Sultan

    The physical (turbidity, color, smell, taste, pH, and conductivity) and geochemical properties (Ca, Mg, Na, Fe, Mn, Al, K, Cl−, HCO3 −, SO4 2−, Fe, Cu, Co, Ni, Zn, Cd, Pb, and Cr) of the drinking water in Gümüşhane city center were determined. This city center constitutes the study area. The pH levels of the water samples ranged from 6.3 to 8.2, and their conductivities ranged between 240 and 900 μS. These findings were concordant with the drinking water standards of the Turkey Standard Institute and the World Health Organization. The hardness of the water samples in the study area was between 18.1 and 115.1 °Fr. These samples were classified as extremely hard, hard, and quite hard. In addition, an assessment using the criteria for Inland Surface Water Classification indicated that considering certain parameters (pH levels, amount of Na, SO4 2−, Fe, Mn, Al, Co, Ni, Cu, and Cr), the samples belonged to class I (high quality) water. When Cl− amount and conductivity were considered, the samples belonged to the first and second classes (less polluted) of water. The water in the study area was generally classified as carbonated and sulfated (Ca + Mg > Na + K) water classes. This water contained more weak acids than strong acids (HCO3 − + CO3 2− > Cl− + SO4 2−). The pH levels (6.3–8.2) of the water in the study area were unrelated to the varying concentrations of metals in the water. Elements such as Fe, Ni, Cd, Pb, Zn, and Cu increase in the water through the water–rock interaction in the area in which water rises or through the mixture of water with either mine or industrial wastes. In addition, several water samples belonged to an acceptable water class for drinking and usage.

    • SDG 6 · Temiz Su ve Sanitasyon
    AtıfScopus9WoS8OpenAlex13
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