Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Uzun, Sevda(77)
- Merdan, Mehmet(73)
- Duran, Celal(54)
- Ozdes, Duygu(50)
- Baltaci, Cemalettin(45)
- Kaygusuz, Abdullah(45)
- Kulakaç, Nurşen(39)
- Ashyralyyev, Charyyar(38)
- Karsli, Orhan(37)
- Demir, Selim(36)
- Öztürk, Serkan(36)
- Dokuz, Abdurrahman(35)
- Turan, Ibrahim(35)
- Araz, Onur(33)
- Kandemir, Raif(31)
- Sipahi, Ferkan(30)
- Topal, Fevzi(30)
- Kurt, Kemal(28)
- Peker, Iskender(28)
- Arslan, Mehmet(27)
- Baltacı, Cemalettin(27)
- Maden, Nafiz(27)
- Ozturk, Samet(27)
- Aydin, Aydanur(26)
- Vural, Alaaddin(26)
- Bayrakdaroglu, Serdar(25)
- Kurnaz, Muammer(25)
- Reis, Hatice Catal(25)
- Akar, Zeynep(24)
- Aydin, Faruk(24)
- Gücer, Mehmet Ali(24)
- Topal, Meryem(24)
- Yolcu, Halil(24)
- Yücel, Cem(24)
- Anaç, Halil(23)
- Kankal, Murat(23)
- Ürkek, Bayram(23)
- Aliyazicioglu, Yuksel(22)
- Günen, Mehmet Akif(22)
- Tuncer, Metin(22)
Yayınlar
- MakaleAçık Erişim2013Scopus SJRQ3Separation and preconcentration of copper in environmental samples on amberlite XAD-8 resin after complexation with a carbothioamide derivative
Elvan, Hamide; Ozdes, Duygu; Duran, Celal; Sahin, Deniz; Tufekci, Mehmet; Bahadir, Zekeriyya
A new solid phase extraction (SPE) method has been developed for the selective separation and preconcentration of Cu (II) ions in food and water samples prior to its flame atomic absorption spectrometry determination. The method is based on the adsorption of the Cu(II)-2-{[4-Amino-3-(4-methylphenyl-5- oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl]acetyl}-N-phenyl hydrazinecarbothioamide complex on Amberlite XAD-8 resin. The metal complex retained on the resin was eluted with 7.5 mL of 2.0 mol L-1 HCl in acetone. The optimum conditions for the SPE of Cu(II) ions were investigated, and the method was subsequently applied to sea water, stream water, rice, tea, and tobacco samples for the determination of Cu(II) levels.
AtıfScopus11WoS11OpenAlex13
İncele - MakaleAçık Erişim2013Scopus SJRQ3Approximate solution of inverse problem for elliptic equation with overdetermination
Ashyralyyev, Charyyar; Dedeturk, Mutlu
A finite difference method for the approximate solution of the inverse problem for the multidimensional elliptic equation with overdetermination is applied. Stability and coercive stability estimates of the first and second orders of accuracy difference schemes for this problem are established. The algorithm for approximate solution is tested in a two-dimensional inverse problem.
AtıfScopus17WoS14OpenAlex15İncele - BildiriYalnız künye2013Three-dimensional modeling of women's talus bone
Catal, Hatice; Corumluoglu, Ozsen; Bayram, Bulent
In this study, semi-automatic region-based digital image processing techniques were used to create 3-dimensional (3D) virtual model of talus bone. 5 ballerinas and 5 sedentary women have voluntarily been involved in to the study. Total 20 right and left feet have been used which have been taken from the multidetector computed tomography (MDCT). We used 3D Doctor Software in this research. Image preprocessing, segmentation and 3D modeling steps were done respectively. Volume, area and length based various statistical ratios were computed according to the measurements. The comparisons have been accomplished by using these ratios for sedentary and ballerinas. As an outcome, some differences were found in talus of ballerina and sedentary women. We hope that the results from the biometric and reconstructive techniques carried out in this study will contribute to the present knowledge in orthopedics and digital image processing in this area.
- MakaleYalnız künye2013Scopus SJRQ1The contribution of hydropower in meeting electric energy needs: The case of Turkey
Akpinar, Adem
In this article, an attempt is made to better understand the contribution of hydropower in meeting electric energy needs of Turkey. Thus, a comparison between Turkey and other countries, which have some similarities with Turkey or which are more developed nations compared to Turkey, for evaluating from different aspects the contribution of hydropower in meeting electric energy needs is performed. The producers of electricity and hydroelectricity in the world, and the electric sectors of all the selected countries are firstly examined. Thereafter, Turkey's water resources and its potential, hydropower potential, and current status of hydropower in Turkey are investigated in detail. A detailed discussion regarding economic and energy indicators, hydroelectricity versus thermal electricity, the contributions of hydroelectricity to the total and renewable electricity generation, and the usage status of hydro potential of each selected nation is also made. Finally, it is found that hydropower is the second largest contributor in meeting Turkey's electric energy needs after thermal, mainly natural gas. It is also estimated that the contribution of hydropower will continue because a vast amount of its economically feasible hydro potential (about 64%) is undeveloped. Besides, it is determined that the contribution of hydropower in the total electricity generation in Turkey is greater than that of China and India, but it is lower than that of Norway, Brazil, and Canada.
AtıfScopus21WoS20OpenAlex27İncele - MakaleAçık Erişim2013Scopus SJRQ1The genesis of the slab window-related Arzular low-sulfidation epithermal gold mineralization (eastern Pontides, NE Turkey)
Akaryali, Enver; Tüysüz, Necati
The Arzular mineralization is one of the best examples of epithermal gold deposits in the eastern Pontides orogenic belt. The mineralization is hosted by the subduction-related basaltic andesites and is mainly controlled by E-W and NE-SW trending fracture zones. The main ore minerals are galena, sphalerite, pyrite, chalcopyrite, tetrahedrite and gold. Homogenization temperatures of fluid inclusions are between 130 and 295 C for quartz and between 90 and 133 C for sphalerite. Sulphur isotope values obtained from pyrite, galena and sphalerite vary between -1.2‰ and 3‰, indicating that sulphur belongs to magmatic origin and was derived from the Lutetian non-adakitic granitic intrusions in the region. Oxygen isotope values are between 15.0‰ and 16.7‰, and hydrogen isotope values are between -87‰ and -91‰. The sulphur isotope thermometer yielded temperatures in the range of 244-291 C for the ore formation. Our results support the hypothesis that the Arzular mineralization is a low-sulfidation epithermal gold deposit associated with non-adakitic subduction-related granitic magmas that were generated by slab window-related processes in a south-dipping subduction zone during the Lutetian.
AtıfScopus25WoS19OpenAlex29İncele - MakaleYalnız künye2013Scopus SJRQ1The effects of antifreeze use on physical and mechanical properties of concrete produced in cold weather
Çullu, Mustafa; Arslan, Metin
This study examined the effects of antifreeze on the physical and mechanical properties of the concrete which are produced in cold weather. 30% Calcium Nitrate and 5% hydroxyethylaminemixture (HEA), Calcium Nitrate (KN) and Polyhydroxy Amine (PA) were used as additives in antifreeze. Prepared concrete samples were placed in a formwork and exposed to the frost at 0 °C, -5°C, -10°C, -15°C and -20°C for 2 days. Afterwards, concrete samples in the freezer were cured at the room temperature until the 28th day and permeable pore space volume, water absorption ratio, density, capillarity ratio, impermeability, compressive strength, static modulus of elasticity, Poisson's ratio and tensile strength values of the concrete samples were determined after the curing. In conclusion, 30% Calcium Nitrate and 5% hydroxyethylaminemixture (HEA) were found to be giving the best performance among the antifreeze types. The physical and mechanical properties of the concrete were negatively affected from all antifreeze types due to the temperature decrease of the exposed fresh concrete.
AtıfScopus47WoS37OpenAlex44İncele - Kitap BölümüYalnız künye2013Factors affecting electronic service brand equity
Yildiz, Salih; Kurtuldu, Hüseyin Sabri
The purpose of this study is to determine the factors affecting electronic service brand equity and to investigate consumers' perceptions of the electronic service brands they prefer. Additionally, the study, based on the Rios and Riquelme's electronic brand equity model, determines whether demographic characteristics of consumers cause significant differences regarding perceptions of electronic service brand equity. Within the context of this study, an electronic service site in the book/magazine sector was employed. The survey sample size was 675 as a result of an electronic survey administered on selected Websites. The reliability of the scales used in the survey was tested via Cronbach's Alfa Method and the validity of the scales were tested via Factor Analysis. Hypotheses of the survey were tested using difference methods (e.g., ANOVA, multiple regression analysis, T-test). It was determined that e-image, e-quality, e-loyalty, e-trust, e-awareness, and e-value factors are effective for developing electronic service brand equity. Furthermore, it can be claimed that age, income, and education cause significant differences regarding perceptions of electronic service brand equity, while gender, occupation, and marital status do not cause significant differences of perceptions regarding the same.
AtıfScopus3OpenAlex3İncele - MakaleAçık Erişim2013Scopus SJRQ3Antioxidant effect of rosehip seed powder in raw and cooked meatballs during refrigerated storage
Ilyasoǧlu, Huri
The aim of this study was to learn the usage ability of rosehip seed powder (RSP) as an antioxidant agent to prevent lipid oxidation in raw and cooked meatballs during refrigerated storage. For this purpose, 4 different formulations (without RSP and with 1%, 2%, and 4% RSP) were prepared. Thiobarbituric acid reactive substances (TBARS) values of the raw and cooked meatballs were determined at 0, 3, 6, 9, and 12 days of storage. Both the raw and the cooked meatballs containing 2% RSP had lower TBARS values at the end of storage compared to the control meatballs. Moreover, the difference in sensorial properties between the cooked control sample and cooked RSP-added test samples was not significant. These results indicated that RSP may be utilized as a natural antioxidant in cooked meatballs.
AtıfScopus12WoS10OpenAlex11TR Dizin1
İncele - MakaleYalnız künye2013Scopus SJRQ3Changes in chemical composition and peroxidase activity of turnip (Brassica rapa) during processing and frozen storage
Okcu, Zühal; Keleş, Fevzi; Şat, Ihsan Güngör
Chemical composition content and peroxidase enzyme activity of raw, canned and frozen turnip roots were determined. The peroxidase activity determined in the roots of raw turnip was 134x105 EU/100 g fresh weight and 170x105 EU/g protein. There were significant changes in the activities of peroxidase of canned and frozen turnip roots, as well as in the contents of protein. The peroxidase activity of canned turnip roots was practically undetectable while there was residual activity after blanching and freezing. Peroxidase is one of the most heat-stable enzymes in plants. This study shows that heat treatment of 3 min at 95°C is preferred for POD activity inactivating compared with other heat treatment. In addition, conserving process inactivated of POD activity, too.
AtıfScopus3WoS2İncele - MakaleYalnız künye2013Scopus SJRQ2Experimental analysis on FEM definition of backfill-rectangular tank-fluid system
Cakir, Tufan; Livaoglu, Ramazan
In the present study, the numerical and experimental investigations were performed on the backfill- exterior wall-fluid interaction systems in case of empty and full tanks. For this, firstly, the non-linear three dimensional (3D) finite element models were developed considering both backfill-wall and fluid-wall interactions, and modal analyses for these systems were carried out in order to acquire modal frequencies and mode shapes by means of ANSYS finite element structural analysis program. Secondly, a series of field tests were fulfilled to define their modal characteristics and to compare the results from proposed approximation in the selected structures. Finally, comparing the theoretical predictions from the finite element models to results from experimental measurements, a close agreement was found between theory and experiment. Thus, it can be easily stated that experimental verifications provide strong support for the finite element models and the proposed procedures themselves are the meritorious approximations to the real problem, and this makes the models appealing for use in further investigations.
AtıfScopus8WoS9OpenAlex7İncele - MakaleYalnız künye2013Scopus SJRQ1Evaluation of wind energy potentiality at coastal locations along the north eastern coasts of Turkey
Akpinar, Adem
This study aims to determine and evaluate wind energy potentiality along coastal locations at the North Eastern of Turkey. For this purpose, the present study has statistically analysed wind power potentials and wind characteristics from six meteorological stations (Sinop, Samsun, Ordu, Giresun, Trabzon, and Hopa) along the North Eastern (NE) geo-political coastal region of Turkey using the hourly or 3-hourly wind speed data measured at 10 m height during 9 years. The diurnal, monthly, and seasonal mean wind speed and wind power density at all the stations are assessed to have remarkable variations. The annual and seasonal frequency distributions and dominant wind directions of the all locations are determined. It is observed that the monthly mean wind speed in this region ranges from 1.53 m/s to 4.06 m/s. The maximum annual mean wind power density was found to be 59.96 W/m2 at Sinop while the maximum annual mean wind energy density was obtained to be 525.25 kWh/m2/year at the same station. It is further shown that Sinop, Hopa, and Trabzon have the higher wind power potential than other locations and their potential are close to each other.
AtıfScopus35WoS36OpenAlex53İncele - MakaleAçık Erişim2013Scopus SJRQ2Development of a new solid phase extraction procedure for selective separation and enrichment of Au(III) ions in environmental samples
Elvan, Hamide; Ozdes, Duygu; Duran, Celal; Bulut, V. Numan; Gümrükçüoglu, Nurhan; Soylak, Mustafa
A highly sensitive, selective and low cost solid phase extraction (SPE) procedure was developed for separation and enrichment of Au(III) ions in environmental samples prior to its flame atomic absorption spectrometric detection. Au(III)-2-pyridin-5-(4-tolyl)-1,3,4-oxadiazole (PYTOX) complex was adsorbed quantitatively on Amberlite XAD-4 resin in 0.5 mol L-1 HNO3 condition and the elution was carried out with 7.5 mL of 1.0 mol L-1 HCl in acetone. Some analytical parameters, affect the recoveries of Au(III) ions, such as HNO3 concentration of sample solution, amount of PYTOX, type, concentration and volume of eluent, sample volume and concomitants were examined. Adopting optimized experimental conditions, the limit of detection for Au(III) ions was 1.03 μg L-1 with preconcentration factor of 50 and a relative standard deviation (RSD) of 3.7%. The determination of Au(III) ions in anodic slime, gold ore, soil and sea and stream waters was performed after checking the accuracy of the method by addition-recovery tests.
AtıfScopus7WoS7OpenAlex6İncele - MakaleYalnız künye2013Scopus SJRQ2Decaying source model: Alternative approach to determination of true counting rates at X and gamma ray counting systems
Karabidak, S.M.; Cevik, U.
The counting systems consisting of electronic devices are used for detection of radiation due to X or gamma rays. The dead time of the counting system is based on time limitations of these electronic devices. The dead time causes counting losses. Determination of counting rate losses in quantitative and qualitative analysis become a vital step for correction of analysis. Therefore, compensating for counting rate losses is of great importance. These counting rate losses are due to piled up reject time, paralyzable or non-paralyzable system dead time or a combination of these mechanisms. Paralyzable and non-paralyzable models are well-known and frequently used for correction of counting rate losses dependent on the system dead time. However, these two models do not provide enough correction at medium and high counting rates. Therefore, the new models for corrections of counting rate losses are needed. For this reason, both an alternative approach is proposed and a simulation program is coded for counting rate losses in this study. A good agreement is obtained between theoretical model and simulation program.
AtıfScopus7WoS6OpenAlex9İncele - MakaleAçık Erişim2013Scopus SJRQ4Effect of some spice essential oils on the stability of frying oils
Tanriverdi, Ebru Sandal; Özcan, Mehmet Musa; Juhaimi, Fahad Al
In this study, peppers and potatoes were fried in olive and peanut oils. In order to evaluate the oxidative stability of frying oils, essential oils of sage, rosemary, thyme at the concentration of 0.3, 0.6, 0.9 and 1.2 %, separately and 0.01 % butylated hydroxytoluene were added into olive and peanut oils. Chemical properties of frying oils (free fatty acid %, peroxide value, DPPH, total phenolic and fatty acid composition) were determined after frying. Butylated hydroxytoluene showed the best effect on free fatty acid % and peroxide value of olive oils after frying of peppers and potatoes. Free fatty acid % values of frying oils of peppers and potatoes showed variation. The nearest values of oleic, linoleic and linolenic acid contents of frying olive oils of peppers and potatoes were determined with sample addition of butylated hydroxytoluene. Oleic, linoleic and linolenic acid contents of peanut oil with butylated hydroxytoluene and potato frying oil that addition of 0.3 % rosemary essential oil were determined to nearly the initial value of oil. These essential oils were also determined to show high radical scavenging effect. Rosemary essential oil was determined higher the radical scavenging effect and lower total phenolic compounds than thyme essential oils. There were not exact a relationship between radical scavenging effect and the amount of total phenolic compounds. The aim of current study is to establish to the effect of some spice essential oils on the stability of frying oils.
- MakaleYalnız künye2013Scopus SJRQ1Effects of charge properties on exergy balance in spark ignition engines
Sezer, Ismet; Bilgin, Atilla
This study investigates the effects of the air-fuel mixture (charge) properties on the exergy balance in spark ignition engines. A thermodynamic cycle model including compression, combustion and expansion processes is used. The principles of the second law are applied to the cycle model to perform an exergy analysis. Variation of the exergetic variables during the investigated portion of the cycle are examined as a function of the charge properties, i.e., fuel-air equivalence ratio, residual gas fraction and initial charge temperature. The results show that increasing fuel-air equivalence ratio causes an increase in irreversibilities and also exergy losses with heat transfer and exhaust gases, but enriching the air-fuel mixture beyond the stoichiometric ratio makes no significant contribution to the exergy transfer with work transfer. A slightly lean mixture also gives the best first and second law efficiencies. It is observed that there is a linear relation between the residual gas fraction and the exergetic variables. An increase in the residual gas fraction decreases the irreversibilities and exergy losses aside from the exergy transfer with work transfer. However, increasing the residual gas fraction positively affects the first and second law efficiencies because of the diluting of the charge. Increase of initial charge temperature creates a reduction in the irreversibilities and the exergy losses and, it also results in a lower exergy output by work transfer. Further, increase of initial charge temperature negatively influences the first and second law efficiencies.
AtıfScopus32WoS28OpenAlex40İncele - MakaleYalnız künye2013Scopus SJRQ2Effects of different curvature patches on the strength of double-strap adhesive joints
Akpinar, Salih
In general, the damage in adhesively bonded joints initiates from and propagates through the ends of the overlap area due to high stress concentration in that area. The reduction of these stress concentrations results in an increase in the strength of the joints. For this reason, the rounding of the overlap region before bonding and then applying compression during the bonding process will exert compressive residual stresses on the adhesive layer in the overlap end regions. It is known that the residual stresses formed in this process increase the failure strength of the joint and hence delay the initiation of the damage. In this study, the effects of overlap length (L = 50,75, and 100 mm), patch thickness (h = 1.6, 3.2, and 5 mm) and patch materials (AA2024 aluminum alloy, AISI 304 steel, AISI 1040 steel) on bond strength were experimentally investigated for adhesively bonded double-strap joint (DSJ) and curvature double-strap joint (CDSJ) subjected totensile loading. The experimental study showed that the overlap length, patch thickness and patch materials have considerable influence on the failure strength and displacement capacity of the joints.
AtıfScopus31WoS29İncele - MakaleYalnız künye2013Scopus SJRQ1Prediction of offshore bar-shape parameters resulted by cross-shore sediment transport using neural network
Kömü rcü, Murat Ihsan; Kömür, Mehmet Aydin; Akpinar, Adem; Özölçer, Ismail Hakki; Yüksek, Ömer
In order to understand the features of coastal zone and to utilize the coastal areas, it is necessary to determine the sediment movement and the resulting transport. Waves, topographic features, and material properties are known as the most important factors affecting the sediment movement and coastal profiles. In this study, by taking into consideration of wave height and period (H0, T), bed slope (m) and sediment diameter (d50), cross-shore sediment movement was studied in a physical model and various bar-shape parameters of the resultant erosion type profile were determined. Using 80 experimental data which are obtained from physical model studies, a neural network (NN) has been calibrated to predict bar-shape parameters of beach profiles. A sensitivity analysis was firstly carried out to decide data of training and test sets. Four different models, in which the rates of their training and testing set data were 80% and 20%, 70% and 30%, 60% and 40%, 50% and 50% were constituted and their performances were compared. It was determined that the model, in which the rate of its training and testing set data was 80% and 20%, respectively, has the best results. Therefore, a total of 64 experimental data were used as training set and the remainders of the experimental data were used as a testing set for the model. The performance of the NN model was compared with the regression equations developed in a previous study and the equations cited in literature indicating better performance over the equations.
AtıfScopus16WoS14OpenAlex22İncele - BildiriYalnız künye2013Self-deploying composite shell reflector antenna for Ku-band missions: 1.5 m diameter demonstrator
Soykasap, Omer; Karakaya, Sukru; Kaplan, Erdar; Ilarslan, M; Ince, F; Kaynak, O; Basturk, S
Carbon fiber reinforced plastic (CFRP) composite shell reflectors have been developed for space borne antennas due to their light weight, high thermal stability, and high surface accuracy. In order to reduce launch cost and structural mass, compactly folding and self-deployment of the reflector is preferred. In this paper, the full-scale offset reflector with a diameter of 6 m was designed by introducing reinforcements in the central region. After modal analysis was carried out for full-scale reflector model, the suitability of design was determined and 1/4-scaled version was manufactured. The experiments of the demonstrator were conducted for modal analysis, folding, dynamic deployment behavior and surface accuracy. As a result of study, new reflector model was successfully designed with low-mass, manufacturing ease, lower cost and has a monolithic structure, which two opposite edges of the reflector can be rolled toward the center of the reflector for packaging.
AtıfScopus4WoS3İncele - MakaleYalnız künye2013Scopus SJRQ3Heavy metal analysis by moss species in the Black Sea region of Turkey
Koz, Bahadir; Cevik, Ugur; Bulut, Volkan Numan; Kaya, Selim; Gundogdu, Ali; Celik, Necati
The heavy metal analysis of mosses in the Black Sea region of Turkey was determined using atomic absorption spectrometry method. The procedure was also validated by analysis of standard reference material (IAEA-336 Lichen). A qualitative analysis showed that the samples contained chromium, manganese, cobalt, nickel, copper, zinc, and lead. While the mean concentration values of Cr, Mn, Co, Ni, Cu, Zn, and Pb in the moss samples collected from city centers are 60.6, 820, 12.2, 18.8, 293, 181 and 39.8 mg.kg-1, the mean concentration values in the moss samples collected from the city intervals are 43.8, 761, 11.0, 15.6, 242, 170 and 38.4 mg.kg-1, respectively. Since this study was a heavy metal analysis along the highway, evaluation of these elements with their potential hazards for ecology and human was briefly discussed. A strong relationship was observed between Pb concentration and the traffic density.
AtıfScopus2WoS2İncele - MakaleAçık Erişim2013Scopus SJRQ2Simulation of a large electric distribution system having intensive harmonics in the industrial zone of Konya
Eroǧlu, Hasan; Aydin, Musa
In this study, measurements were taken at difierent points of a sample distribution system in order to analyze the levels of harmonics that appear as a day-to-day increasing problem in electrical distribution systems. According to the measurement values, the dominant harmonics have been determined and an electrical model of the system has been prepared using the SimPowerSystems toolbox from MATLAB and Simulink. The accuracy of the electrical model has been verified by the measurement and simulation values. In addition, the transformer connection types' and impedances' simulations have been presented to understand and solve the harmonic problems in electrical distribution systems. With the help of this study, advanced analysis can be performed in the electrical distribution system for power quality analyses and this study can be a background for similar kinds of simulation studies.
AtıfOpenAlex1İncele