Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Uzun, Sevda(66)
- Merdan, Mehmet(56)
- Duran, Celal(50)
- Ozdes, Duygu(47)
- Kaygusuz, Abdullah(42)
- Demir, Selim(37)
- Turan, Ibrahim(37)
- Ashyralyyev, Charyyar(34)
- Dokuz, Abdurrahman(33)
- Araz, Onur(31)
- Öztürk, Serkan(31)
- Sipahi, Ferkan(30)
- Kandemir, Raif(28)
- Arslan, Mehmet(27)
- Karsli, Orhan(27)
- Kulakaç, Nurşen(26)
- Baltacı, Cemalettin(25)
- Gücer, Mehmet Ali(25)
- Kurt, Kemal(25)
- Maden, Nafiz(25)
- Ozturk, Samet(25)
- Topal, Fevzi(25)
- Baltaci, Cemalettin(24)
- Yücel, Cem(24)
- Aliyazicioglu, Yuksel(23)
- Bayrakdaroglu, Serdar(23)
- Kankal, Murat(23)
- Peker, Iskender(23)
- Yolcu, Halil(23)
- Reis, Hatice Catal(21)
- Topal, Meryem(21)
- Vural, Alaaddin(21)
- Aydin, Aydanur(20)
- Aydin, Faruk(20)
- Bayraktar, Alemdar(20)
- Kurnaz, Muammer(20)
- Çelik, Necati(20)
- Ürkek, Bayram(20)
- Cakir, Tufan(18)
- Günen, Mehmet Akif(18)
Yayınlar
- MakaleYalnız künye2014Scopus SJRQ2EFFECT OF HEAT TREATMENT ON STRUCTURE OF ELECTROLESS Ni-B COATED PURE TITANIUM
Bülbül, Ferhat; Çelik, Ilhan
Pure titanium has a very large potential for use industrially due to its low weight, however, its usage continues to be limited because it possesses some disadvantages such as low hardness and wear resistance, weak corrosion resistance in high temperatures and high cost. In order to strengthen these weaknesses of pure titanium, electroless Ni-B deposition process, may be an alternative solution. In this study, the Ni-B coatings were deposited on pure titanium and annealed at the temperatures of 450 degrees C, 650 degrees C and 850 degrees C. The non-heat treated and heat treated coatings were structurally characterized via SEM (scanning electron microscope) and XRD (x ray diffraction). These coatings transformed from amorphous structure to a pronounced crystalline structure depending on heat treatment.
AtıfWoS9TR Dizin2
İncele - MakaleAçık Erişim2014Scopus SJRQ2Assessment of kinetics, thermodynamics, and equilibrium parameters of Cu(II) adsorption onto Rosa canina seeds
Serencam, Huseyin; Ozdes, Duygu; Duran, Celal; Senturk, Hasan Basri
Rosa canina seeds (RCS) is considered as a low-cost and promising adsorbent in removal of metal ions; hence, in the present study, we aimed to test the adsorptive removal of Cu(II) ions from aqueous solutions by utilizing RCS in a batch process. After characterization of RCS by using several techniques, the effects of various experimental parameters such as initial pH of aqueous solution, contact time, initial Cu(II) concentration, RCS concentration, temperature, and electrolyte concentration were studied upon the adsorption process. The desorption conditions of Cu(II) ions from the loaded RCS were also evaluated. Maximum Cu(II) adsorption was found to occur at pH 6.0 and the equilibrium was established after 60 min of contact time. The adsorption isotherms were described by means of Langmuir, Freundlich, Temkin, and Dubinin Radushkevich models. The adsorption kinetics were analyzed using pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion models and the adsorption data were well described by the pseudo-second-order model. Thermodynamic parameters such as the Gibbs free energy (ΔG), enthalpy (ΔH), and entropy (ΔS) changes were also evaluated and it has been found that the adsorption process was feasible, spontaneous, and endothermic in the temperature range of 278-313 K.
AtıfScopus19WoS20OpenAlex19
İncele - MakaleYalnız künye2014Scopus SJRQ1Assessment of liquefaction potential of Erzincan Province and its vicinity, Turkey
Subası Duman, E.; Ikizler, S.B.
One of the most important causes of damages after the earthquakes is the soil liquefaction. Liquefaction can be defined as temporary loss in strength of saturated sandy and silty deposits under transient and cyclic loadings due to excess pore water pressure. This study includes determination of liquefaction potential in Erzincan city center and its vicinity. Due to the proximity of the North Anatolian Fault Zone, in a probable earthquake, Erzincan Province is thought to be affected. In this context, the earthquake scenarios were produced using the empirical expressions. Liquefaction potential for different earthquake magnitudes was determined. These earthquake magnitudes were selected as 6.0, 6.5, 7.0, 7.5, respectively. Liquefaction potential was investigated using standard penetration test (SPT) data. The first stage of the study, 63 boreholes in different locations was drilled and SPT was performed. Disturbed and undisturbed soil samples were taken from these boreholes. Laboratory testing was performed to determine physical properties of soil samples, and liquefaction potential analyses were examined using three methods, namely Seed and Idriss (J Soil Mech Found Div ASCE 97(9):1249-1273, 1971), Tokimatsu and Yoshimi (Soil Found 23(4):56-74, 1983), Iwasaki et al. (Soil liquefaction potential evaluation with use of the simplified procedure. International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics, St. Louis, pp 209-214, 1981). In order to complete liquefaction analysis within a short time, MATLAB program was prepared. Liquefaction potential analyses were carried out with the MATLAB program. At the final stage of this study, liquefaction potential maps were prepared for different earthquake magnitudes. The expected results will be shared with the local authorities and important engineering remedial measurements will be proposed to prevent further life losses and to mitigate property losses.
AtıfScopus6WoS3OpenAlex7İncele - BildiriAçık Erişim2014Scopus SJRQ3Suggestion of new formulations for schmidt hammer and UPV test methods for concrete
Cavdar, A.; Bingöl, S.
The concrete is the most widely used building material in Turkey. Especially reinforced concrete dominates at building sector. Because of concrete is an non-homogeneous and non-isotropic material, the strength of concrete cannot be accurately achieved at the site. To control the mechanical properties of concrete in the site, non- -destructive test methods can be used. They are useful for having no damage on concrete, however these test results sometimes gives deceptive results. In this study, two of non-destructive test methods, Schmidt hammer testing and ultrasonic pulse velocity methods were used for determining concrete compressive strength. 101 samples were poured concrete cube dimensions 150×150×150 mm3. On 28th days, firstly, the samples were applied Schmidt hammer test and ultrasonic pulse velocity test and then the compressive strength of these samples was measured by breaking in the press, destructive method. Thus, the new formulations are obtained for Schmidt hammer test and ultrasonic pulse velocity test.
AtıfScopus4WoS3OpenAlex3İncele - Derleme MakaleYalnız künye2014Scopus SJRQ2On the solutions of nonlinear fractional Klein-Gordon equation with modified Riemann-Liouville derivative
Merdan, Mehmet
In this paper, fractional variational iteration method (FVIM) is applied for finding approximate analytical solutions of nonlinear fractional Klein-Gordon equation. Time-fractional derivative is described in the Riemann-Liouville sense. A new application of fractional variational iteration method (FVIM) is extended to derive analytical solutions in the form of a series for this equation. The behavior of the solutions and the effects of different values of fractional order α are indicated graphically. It is shown that the solutions obtained by the FVIM are reliable, convenient and effective for strongly nonlinear partial equations with modified Riemann-Liouville derivative.
AtıfScopus11WoS11İncele - MakaleAçık Erişim2014Scopus SJRQ3Is the combined use of insulin resistance indices, Including adipokines, more reliable in metabolic syndrome?
Kural, Birgül; Değer, Orhan; Erem, Cihangir; Balaban Yücesan, Fulya; Aliyazicioğlu, Rezzan; Barlak, Yaşam
Background/aim: To determine the levels of adipokines (leptin, adiponectin, resistin, and visfatin) and the indices of insulin sensitivity/ resistance, and to examine the relationship among them in patients with metabolic syndrome (MetS).; Materials and methods: The study groups included 45 subjects with MetS (31 women/14 men), and 45 sex- and age-matched non-MetS healthy volunteers (31 women/14 men). The levels of adipokines were determined by enzyme-linked immunosorbent assay.; Results: The levels of leptin and visfatin were significantly higher in the MetS than in the non-MetS subjects (P < 0.01). There was no difference in adiponectin levels in subjects with and without MetS (P = 0.052). Similarly, resistin did not show any statistically significant difference. A statistically significant positive correlation of leptin with insulin levels was observed, while negative correlations of visfatin levels with age, and resistin levels with the ratio of adiponectin to leptin, were found in the MetS (P < 0.05). The combination of adipokines, insulin resistance-sensitivity parameters, and MetS criteria parameters gave more signifcant differences than a single parameter.; Conclusion: Since the parameters mentioned above might affect, interact with, and/or interfere with each other, the combinations of these parameters might give more reliable results to evaluate the insulin resistance/sensitivity in MetS patients.
AtıfScopus7WoS7OpenAlex8
İncele - BildiriYalnız künye2014Effects of discretization schemes on numerical results of natural convection heat transfer
Sahin, Birol; Ashyralyev, A; Malkowsky, E
Two dimensional natural convection heat transfer in a square enclosure is numerically analyzed. Laminar naturalconvection heat transfer is studied by solving the Navier-Stokes and energy equations using finite volume method. Numerical solutions of flow field are obtained by Semi-Implicit Method for Pressure-Linked Equations (SIMPLE). Effects of the discretization schemes on numerical solutions are compared with each other.
- BildiriYalnız künye2014Weyl numbers of diagonal matrices
Ismailov, Zameddin I.; Cona, Lale; Çevik, Elif Otkun; Guler, Bahadir O.; Ashyralyev, A; Malkowsky, E
In this work, a connection between Weyl numbers of the infinite diagonal matrix with linear bounded operator elements in the direct sum of Banach spaces and its coordinate operators has been investigated.
AtıfScopus1OpenAlex2İncele - MakaleYalnız künye2014Scopus SJRQ3Well-posedness of fractional parabolic differential and difference equations with Dirichlet-Neumann conditions
Ashyralyev, Allaberen; Emirov, Nazar; Cakir, Zafer
We study initial-boundary value problems for fractional parabolic equations with the Dirichlet-Neumann conditions. We obtain a stable difference schemes for this problem, and obtain theorems on coercive stability estimates for the solution of the first order of accuracy difference scheme. A procedure of modified Gauss elimination method is applied for the solution of the first and second order of accuracy difference schemes of one-dimensional fractional parabolic differential equations.
AtıfScopus12WoS6İncele - MakaleAçık Erişim2014Scopus SJRQ2High order of accuracy difference schemes for the inverse elliptic problem with Dirichlet condition
Ashyralyyev, Charyyar
The overdetermination problem for elliptic differential equation with Dirichlet boundary condition is considered. The third and fourth orders of accuracy stable difference schemes for the solution of this inverse problem are presented. Stability, almost coercive stability, and coercive inequalities for the solutions of difference problems are established. As a result of the application of established abstract theorems, we get well-posedness of high order difference schemes of the inverse problem for a multidimensional elliptic equation. The theoretical statements are supported by a numerical example.
AtıfScopus30WoS29OpenAlex26İncele - MakaleYalnız künye2014Scopus SJRQ3The effect of different photoperiods and stocking densities on fattening performance, Carcass and some stress parameters in broilers
Das, H.; Lacin, E.
This study was carried out for the purpose of investigating the effects of different photoperiods and stocking densities on physiologic parameters such as body weight, feed consumption, feed efficiency, carcass traits and some stress parameters in broiler chickens. Throughout the experiment, 480 day-old male chickens obtained from a commercial hatchery were used. The chicks were placed in different partitions which had three different photoperiod (continuous lighting: 24 hour light, constant lighting: 16 hour light - 8 hour dark, intermittent lighting: 4 hour light – 2 hour dark) were applied. Each photoperiod group was formed with five replicates at two different stocking densities (normal stocking density: 12 broiler/m2, high stocking density: 20 broiler/m2). The experiment was carried for 42 days. At the end of the experiment, the effect of photoperiod and stocking density on live weight gain were significant (P<0.05) while photoperiod significantly affected the feed consumption only (P<0.05). The feed efficiency were insignificant (P>0.05) with respect to both factors. The photoperiod programs had significant effects on the relative weight of gizzard, blood, feather percentage values (P<0.05) and breast percentage values (P<0.01). The stocking density has a significant effect on relative heart weight (P<0.05) and entire thigh values (P<0.01). At the end of the experiment, it was ascertained that the photoperiod program and stocking density had no significant (P>0.05) difference on tonic immobility and tibial dyschondroplasia values. However, stocking density had a highly significant effect (P<0.01) on gait score values and on heterophil-lymphocyte rate values (P<0.01).
AtıfScopus22WoS21İncele - MakaleAçık Erişim2014Scopus SJRQ3On some geometric properties of a new paranormed sequence space
Karakaya, Vatan; Altun, Fatma
We introduce a new sequence space which is defined by the operator W=(wnk) on the sequence space ℓ(p). We define a modular functional on this space and investigate structure of this space equipped with Luxemburg norm. Also we study some geometric properties which are called Kadec-Klee, k-NUC, and uniform Opial properties and prove that this new space possesses these properties.
AtıfScopus4WoS2OpenAlex5İncele - MakaleYalnız künye2014Scopus SJRQ1The petrogenesis of Early Eocene non-adakitic volcanism in NE Turkey: Constraints on the geodynamic implications
Aydinçakir, Emre
Whole-rock geochemistry, mineral chemistry, the 40Ar-39Ar age, and Sr-Nd isotopic data are presented for the Early Eocene non-adakitic volcanic rocks on the eastern corner of the Eastern Pontides orogenic belt (NE Turkey). The tectonic setting of the Eastern Pontides during the Late Mesozoic to Early Cenozoic remains a topic of debate. Here, for the first time, we describe the Early Eocene non-adakitic volcanic rocks from the Eastern Pontides. These rocks contain plagioclase, hornblende phenocrysts, and magnetite/titanomagnetite and apatite microphenocrysts. Geochronology studies based on the 40Ar-39Ar ratio of the amphibole separates reveal that the non-adakitic porphyritic volcanic rocks have a crystallization age of 50.04±0.10 to 50.47±0.22Ma (Ypresian). The volcanic rocks show tholeiitic to calc-alkaline affinities and have low-to-medium K contents. They are also enriched in large-ion lithophile elements (LILE), light rare-earth elements (LREE), and depleted in high field strength elements (HFSE), with a no negative Eu anomaly (Eun/Eu*=1.03-1.08) in mantle-normalized trace element spidergrams. The samples (Lacn/Lucn=2.60-4.28) show low-to-medium enrichment in LREEs relative to HREEs, in chondrite-normalized REE patterns indicating similar sources for the rock suite. These rocks display a range of ISr (50Ma) values from 0.70451 to 0.70485, and E{open}Nd (50Ma) 2.9 and 3.7. The main solidification processes involved in the evolution of these volcanics consist of fractional crystallization, with minor amounts of crustal contamination. All of our evidence supports the conclusion that the parental magma of the rocks probably derived from an enriched mantle, previously metasomatized by fluids derived from the subducted slab, in a post-collisional, geodynamic setting.
AtıfScopus58WoS53OpenAlex55İncele - MakaleAçık Erişim2014Scopus SJRQ3On the problem of determining the parameter of an elliptic equation in a banach space
Ashyralyev, Allaberen; Ashyralyyev, Charyyar
The boundary value problem of determining the parameter of an elliptic equation -u(t) + Au(t) = f(t) + p (0 ≤ t ≤ T), u(0) = φ, u(T) = ψ u(λ) = ξ 0 < λ < T, with a positive operator A in an arbitrary Banach space E is studied. The exact estimates are obtained for the solution of this problem in Hölder norms. Coercive stability estimates for the solution of boundary value problems for multi-dimensional elliptic equations are established.
AtıfScopus67WoS58OpenAlex63İncele - MakaleYalnız künye2014Scopus SJRQ1Strength and ultrasonic properties of cemented paste backfill
Ercikdi, Bayram; Yilmaz, Tekin; Külekci, Gökhan
This paper presents the strength (UCS) and ultrasonic pulse velocity (UPV) properties of cemented paste backfill (CPB) produced from two different mill tailings (Tailings T1 and T2). A total of 240 CPB samples with diameter × height of 5 × 10 cm and 10 × 20 cm prepared at different binder dosages (5-7 wt.%) and water-to-cement ratios (3.97-5.10) were subjected to the UPV and UCS tests at 7, 14, 28 and 56-days of curing periods. UCS and UPV of CPB samples increased with increasing the binder dosage and reducing the w/c ratio irrespective of the sample size and tailings type. CPB samples with a diameter × height of 5 × 10 cm were observed to produce consistently higher (up to 1.69-fold) UCSs than those of 10 × 20 cm CPB samples at all binder dosages and w/c ratios. However, at the corresponding binder dosages and w/c ratios, the maximum variation of UPV between the CPB samples of 5 × 10 cm and 10 × 20 cm was only 7.45%. Using the method of least squares regression, the UCS values were correlated with the UPV values for CPB samples of 10 × 20 cm in size. A linear relation with a high correlation coefficient appeared to exist between the UCS and UPV for CPB samples. These findings suggest that the UPV is essentially independent of the sample size. In this regard, the UPV test can be suitably exploited for the rapid estimation of the strength and quality of CPB samples even using small samples with concomitant benefits of reducing sample size.
AtıfScopus126WoS108OpenAlex125İncele - MakaleYalnız künye2014Scopus SJRQ1Assessment of strength properties of cemented paste backfill by ultrasonic pulse velocity test
Yilmaz, Tekin; Ercikdi, Bayram; Karaman, Kadir; Külekçi, Gökhan
Ultrasonic pulse velocity (UPV) test is one of the most popular non-destructive techniques used in the assessment of the mechanical properties of concrete or rock materials. In this study, the effects of binder type/dosage, water to cement ratio (w/c) and fines content (<20 μm) of the tailings on ultrasonic pulse velocity (UPV) of cemented paste backfill (CPB) samples were investigated and correlated with the corresponding unconfined compressive strength (UCS) data. A total of 96 CPB samples prepared at different mixture properties were subjected to the UPV and UCS tests at 7, 14, 28 and 56-days of curing periods. UPV and UCS of CPB samples of ordinary Portland cement (CEM I 42.5 R) and sulphate resistant cement (SRC 32.5) initially increased rapidly, but, slowed down after 14 days. However, UPV and UCS of CPB samples of the blast furnace slag cement (CEM III/A 42.5 N) steadily increased between 7 and 56 days. Increasing binder dosage or reducing w/c ratio and fines content (<20 μm) increased the UCS and UPV of CPB samples. UPV was found to be particularly sensitive to fines content. UCS data were correlated with the corresponding UPV data. A linear relation appeared to exist between the UCS and UPV of CPB samples. These findings have demonstrated that the UPV test can be reliably used for the estimation of the strength of CPB samples.
AtıfScopus145WoS133OpenAlex136İncele - BildiriAçık Erişim2014Scopus SJRQ3Performance analysis of linear permanent magnets synchronous motor by scalar control method (v/f)
Otkun, ÖZcan; Doğan, R. ÖZgüR; Akpinar, A. Sefa; Ma, M.; Wu, A.F.; Afrasiabi, Z.
This study is conducted to improve the performance of Linear Permanent Magnet Synchronous Motor by using Scalar Control Method. To do this, open and closed loop control methods are used. The study is modeled with MATLAB/SIMULINK. Firstly, the Simulink model has been developed by using equations dq axis system of the motor. Then, a scalar control method is modeled. Thirdly, open and closed loop control forms are modeled. From these models, current, thrust force, and speed graphs were obtained. It is seen on the graphs, the motor’s closed loop PID control at scalar control method provide positive results.
- MakaleYalnız künye2014Scopus SJRQ3Backfill and subsoil interaction effects on seismic behavior of a cantilever wall
Cakir, Tufan
The main focus of the current study is to evaluate the dynamic behavior of a cantilever retaining wall considering backfill and soil/foundation interaction effects. For this purpose, a three-dimensional finite element model (FEM) with viscous boundary is developed to investigate the seismic response of the cantilever wall. To demonstrate the validity of the FEM, analytical examinations are carried out by using modal analysis technique. The model verification is accomplished by comparing its predictions to results from analytical method with satisfactory agreement. The method is then employed to further investigate parametrically the effects of not only backfill but also soil/foundation interactions. By means of changing the soil properties, some comparisons are made on lateral displacements and stress responses. It is concluded that the lateral displacements and stresses in the wall are remarkably affected by backfill and subsoil interactions, and the dynamic behavior of the cantilever retaining wall is highly sensitive to mechanical properties of the soil material.
AtıfScopus21WoS18OpenAlex19İncele - MakaleAçık Erişim2014Scopus SJRQ2Updated checklist of harvestmen (Arachnida: Opiliones) in Turkey
Kurt, Kemal
In this work, faunistic studies on harvestmen from Turkey are reviewed. A total of 88 species and 7 subspecies from 35 genera belonging to 7 families were determined. The distribution in Turkey and the world of these taxa is given and their distribution in the geographical regions of Turkey are presented.
AtıfScopus27WoS26OpenAlex25İncele - MakaleAçık Erişim2014Scopus SJRQ2R-modified crank-nicholson difference scheme for fractional parabolic pde
Ashyralyev, Allaberen; Cakir, Zafer
The second order of accuracy stable difference scheme for the numerical solution of the mixed problem for the fractional parabolic equation are presented using by r-modified Crank-Nicholson difference scheme. Stability estimate for the solution of this difference scheme is obtained. A procedure of modified Gauss elimination method is used for solving this difference scheme in the case of one-dimensional fractional parabolic partial differential equations. Numerical results for this scheme and the Crank-Nicholson scheme are compared in test examples.
AtıfScopus5WoS2OpenAlex5İncele