Koleksiyon/r/bayburt/10001

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Koleksiyondaki öğeler

  • MakaleAçık Erişim2011Scopus SJRQ2
    Airy's functions in nonlocal elasticity

    Altan, Burhanettin S.

    Nanostructured devices and materials, such as carbon nanotubes, Atomic Force Microscope, MEMS, etc. attract increasing attention in the scientific world. It has been realized that the classical elasticity is not capable to capture the mechanical behavior of them precisely. There is a wide consensus among the scientists that nonlocal elasticity is more capable than the classical counterpart to model the mechanical behavior of nanostructured materials and devices. In this paper a method which is useful for solving problems in nonlocal is introduced. Airy's stress functions for plane stress problems in nonlocal elasticity are studied. The nonlocal constitutive equations in integral form are discussed and a method is suggested to invert the constitutive equation which allows expressing strains in terms of stresses. A qualitative discussion is given on this inversion process. For the nonlocality kernel of exponential form, the differential equation for Airy's functions in nonlocal elasticity is obtained by introducing the strains into the compatibility condition. Appropriate polynomial forms for the Airy's function are considered and are applied to solve beam bending problems. The solutions are compared with their classical counterparts. The results are given in a series of figures and tables and are discussed in detail. This paper is concluded by indicating the implications of the presented study in nanomechanics and nanotechnology.

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  • Derleme MakaleYalnız künye2012Scopus SJRQ1
    Developing an attitude scale towards using instructional technologies for pre-service teachers

    Metin, Mustafa; Kaleli Yilmaz, Gül; Coşkun, Kerem; Birişçi, Salih

    The aim of this study is to develop an attitude scale towards using instructional technologies (USIT) for preservice teachers. The research was carried out with 1235 pre-service teachers that 567(45.9%) were freshman; 401 (32.5%) were sophomore; 151 (12.2%) were junior and 116 (9.4%) were senior students at different universities in Turkey. The study consists of five parts including literature review, item pool, experts' opinions, administration of scale and computing the reliability and validity. While constituting the item pool, an interview was carried out with 15 pre-service teachers related to instructional technologies. Among from 55 items which are directly related with the subject of attitude or which are selected from the relevant interviews. 45 of them were edited by expert opinions the five point likert type. The draft scale was administered to 1235 pre-service teachers. As a result of factor analysis, the number of items was reduced to 37. After carring out factor analysis the Cronbach-Alpha internal integrity coefficient of the final version of the scale was found as 0.949. By computing the reliability of USIT, the scale was ready to be used.

    AtıfScopus17
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  • MakaleYalnız künye2010Scopus SJRQ2
    Improvements on slope diffraction for multiple wedges

    Tabakcioglu, Mehmet Baris; Kara, Ali

    This article proposes an improved slope uniform theory of diffraction model for fast and more accurate field prediction for multiple wedge diffractions in the transition zone. The proposed method is based on the slope uniform theory of diffraction and the Fresnel zone concept, called the slope uniform theory of diffraction with convex hull. The article also provides simulation results for the comparison of the uniform theory of diffraction based algorithms with respect to the computation time and accuracy.

    AtıfScopus23WoS19OpenAlex23
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  • Derleme MakaleYalnız künye2013Scopus SJRQ1
    Toward a sustainable energy future in Turkey: An environmental perspective

    Serencam, Huseyin; Serencam, Ugur

    As long as the energy future of Turkey is concerned there is a consensus among all parties involved in the subject that a strong sustainability based on diverse range of renewable and variety of sources with efficient and fair use of energy is a must. The main criterion in this approach is to use energy with the least possible greenhouse gases and other harmful emissions. A shift in focus to meeting the needs of energy service sector will be immediately felt in the sustainable energy future in Turkey. Another important aspect of the sustainable energy future of Turkey is that all energy users, as more knowledgeable and active participants will be more involved in various stages of the process. However, Turkey has a long way to reach this vision, because of growing greenhouse emissions related to energy production and utilization of alternative energy is slow. Besides, the intensity of energy of the Turkish economy is decreasing slower than many other OECD countries. In addition, energy consumption per person in Turkey is far above the service needs, even for modern lifestyles. There are substantial obstacles on the way to a sustainable energy future of Turkey, such as various aspects of economic structure, a misdirected energy market process, and a lack of vision among the decision makers.

    • SDG 7 · Erişilebilir ve Temiz Enerji
    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    • SDG 12 · Sorumlu Üretim ve Tüketim
    • SDG 13 · İklim Eylemi
    AtıfScopus12WoS10OpenAlex12
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  • MakaleAçık Erişim2012Scopus SJRQ3
    Changes in carbonic anhydrase activity and gene expression of Hsp70 in rainbow trout (Oncorhynchus mykiss) muscle after exposure to some metals

    Söyüt, Hakan; Beydemir, Sükrü; Ceyhun, Saltuk Buǧrahan; Erdoǧan, Orhan; Kaya, Elif Duygu

    The effects of some heavy metals Co(II), Cu(II), Zn(II), and Ag(I) on carbonic anhydrase (CA) activity from rainbow trout (RT) muscle were investigated. Moreover, the effects of these metals on the expression of heat shock protein 70 (Hsp70) gene in muscle tissue were examined by real-time quantitative PCR (RT-PCR) in muscle tissue aft er exposure to the metals at the end of 6, 12, 24, and 48 h. CA was purified with a specific activity of 2300 EU mg-1, a yield of 19%, and 1080-fold. The molecular weights (Mw) of subunit and native enzyme were approximately 30 and 31 kDa, respectively. Optimum pH, stable pH, optimum temperature, activation energy (Eα), activation enthalpy (ΔH), and Q10 (the difference in activity of enzyme caused by the increment of 10 oC) value were determined. Apparent Michaelis constant (Km), maximum reaction rate (Vmax), and turnover rate of the enzyme (Kcat) values were 1.29 mM, 0.17 μmol min-1, and 28.8 s-1, respectively. The catalytic efficiency (Kcat/Km) was 22.3. The heavy metals decreased in vitro CA activity. Inhibition mechanisms of the metal ions were noncompetitive, except for the Co(II) ion, which was competitive. The expression of the Hsp70 gene was increased in the presence of the metal ions. The expression level at the end of 48 h was the highest for all of the metals. Consequently, the in vitro inhibition rank order was determined as Co(II) > Zn(II) > Cu(II) > Ag(I). Interestingly, Ag(I) was the most effective metal ion on Hsp70 gene expression.

    AtıfScopus9WoS8OpenAlex9
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  • MakaleAçık Erişim2008
    Endurance training attenuates the oxidative stress due to acute exhaustive exercise in rat liver

    Taysi, S.; Oztasan, N.; Efe, H.; Polat, M.F.; Gumustekin, K.; Siktar, E.; Canakci, E.; Akcay, F.; Dane, S.; Gul, M.

    The aim of this study was to investigate whether an 8-week treadmill training attenuates exerciseinduced oxidative stress in rat liver. Male rats were divided into untrained and trained groups. Endurance training consisted of treadmill running at a speed of 2.1 km/h, 1.5 h/day, 5 days a week for 8 weeks. To see the effects of endurance training on acute exhaustive exercise induced oxidative stress, untrained and trained rats were further devided into two groups: animals killed at rest and those killed after acute exhaustive exercise, in which the rats run at 2.1 km/h (10% uphill) until exhaustion. Acute exhaustive exercise increased malondialdehyde level in untrained but not in trained rats. It decreased the activity of glutathione peroxidase and total (enzymatic plus non-enzymatic) superoxide scavenger activity in untrained rats and catalase activity in trained rats. However, it did not affect glutathione S-transferase, glutathione reductase, superoxide dismutase and non-enzymatic superoxide radical scavenger activities in both trained and untrained rats. On the other hand, endurance training decreased glutathione peroxidase and glutathione S-transferase activities. The results suggested that endurance training attenuated exercise-induced oxidative stress in liver, probably by preventing the decreases in glutathione peroxidase and total superoxide scavenger activities during exercise.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus30OpenAlex31
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  • MakaleYalnız künye2011Scopus SJRQ1
    Synthesis of sterically constrained tricyclic pyrrolidinyl alcohol ligands for the enantioselective ethylation of aryl aldehydes: Assessment of the influence of ring strain and N-alkyl chain length on asymmetric induction

    Sahin, Engin; Kilic, Hamdullah

    A series of chiral sterically constrained tricyclic pyrrolidinyl alcohol ligands were synthesized from the appropriate amino acids, and a comparative study of the activity and selectivity of the ligands for the enantioselective ethylation of aromatic aldehydes was carried out. The results obtained were compared with those previously reported for related monocyclic analogues; it was found that the bicyclo[2.2.2]octane backbone fused to pyrrolidine and the groups attached to the carbinol centre, as well as the chain length of the β-amino alcohol, had a marked effect on the enantioselectivity. The enantioselective addition of dialkylzincs to aryl aldehydes in the presence of ligands with diethyl substituents on the carbinol carbon afforded (R)-sec-alcohols in up to 99% enantiomeric excess (ee).

    AtıfScopus5WoS5OpenAlex7
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  • MakaleYalnız künye2012Scopus SJRQ1
    Multi-criteria decision making methods based weighted SERVQUAL scales to measure perceived service quality in hospitals: A case study from Turkey

    Altuntas, Serkan; Dereli, Türkay; Yilmaz, Mustafa Kemal

    The main objectives of this study are to: (i) measure hospital service quality by using analytic hierarchy process (AHP) and analytic network process (ANP) as a multi-criteria decision making method to acquire the relationship and the level of the importance among service quality measurement (SERVQUAL) dimension; (ii) find perceived service quality with respect to different hospital classes (A, B and C) in Istanbul, Turkey; (iii) compare AHP- and ANP-based weighted SERVQUAL scales with the unweighted SERVQUAL scale for public hospital service quality in terms of different hospital classes (A-B and C). First, four hospitals are selected randomly for each class and then, a questionnaire based on the SERVQUAL model is conducted for each class to measure perceived service quality with respect to five major criteria, namely tangible, reliability, responsiveness, assurance and empathy, from patients' viewpoints at hospitals. Next, the second questionnaire based on ANP is developed to evaluate the importance of criteria and construct the relations among the criteria. The study sample contains 281 outpatients totally. Three important findings are obtained in this study. First, there is a significant difference among different hospital classes regarding the perceived service quality. Second, according to the patients, the most important service quality dimensions are empathy, the knowledge of employees, sympathetic and reassuring employees, services provided at the time promised to do so, and safe feeling of patients in interactions with hospital employees. Thirdly, the, perceived service quality through the AHP- and ANP-based SERVQUAL scale is higher than that with the unweighted SERVQUAL scale.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus93WoS74OpenAlex100
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  • MakaleYalnız künye2012Scopus SJRQ4
    Investigation of anti-oxidative and anti-genotoxic effects of Origanum vulgare L. essential oil on human lymphocytes in vitro

    Ceker, Selcuk; Agar, Guleray; Nardemir, Gokce; Anar, Mustafa; Kizil, Hamit Emre; Alpsoy, Lokman

    Origanum vulgare L. (Lamiaceae) is a flavoring herb widely using around the world. Some preparations and extracts from O. vulgare have been used in Turkish traditional medicine to treat several ailments including digestive disorders and menstrual problems. This study is designed to examine the chemical composition and in vitro antigenotoxic and antioxidant activity of the essential oil of O. vulgare (OVE) from Turkey. The essential oil of O. vulgare was analized by using GC. OVEs that were investigated antagonistic effects against oxidative stress and the genotoxic effects of aflatoksin B1 (AFB1). Anti-genotoxic activity was evaluated by sister chromatid exchanges (SCEs) and micronucleus (MN) tests. In additional to investigating protective role of OVEs against the oxidative stress of AFB1 in vitro, oxidative status was assessed on erythrocytes by measuring following oxidative stress markers like; super oxide dismutase (SOD), glutathione peroxidase (GPx), malondialdehyde (MDA).The total of the 25 identified components are accounted for 96.03 % (GC). Major components of the oil were β-caryophyllene (20.40%), and caryophyllene oxide (34.44%). In the SCE and MN tests, it was observed that OVEs suppressed the mutagenic effects of AFB1. OVEs were observed to modulate the adverse effects of AFB1. The results of this experiment clearly reveal that OVEs have strong anti-oxidative and anti-genotoxic effect. These anti-genotoxic effects of O. vulgare essential oils are probably related to its action on the enzymatic activation system. Anti-oxidative and anti-genotoxic effect may be role of these compounds (β-caryophyllene and caryophyllene oxide).

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus14WoS16OpenAlex12
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  • BildiriYalnız künye2005Scopus SJRQ4
    Effect of temperature for the adsorption of methylene blue onto activated carbon produced from waste dogrose seeds

    Gürses, Ahmet; Doǧar, Çetin; Açikyildiz, Metin; Özkan, Esra; Bayrak, Ramis

    Activated carbon, produced from dogrose (Rosa section Caninae) seeds, was used for the removal of methylene blue (basic dye). Adsorption studies were carried out at 20°C and 40°C at various initial dye concentrations (20, 40, 60, 80, and 100 mg/L) and at different lengths of time (15, 30, 60, and 120 min). Adsorption isotherms of the basic dye on the prepared adsorbent were determined and correlated with common isotherm equations. Fitting of the isotherm data to the BET adsorption isotherm model was better in high concentration ranges than in the other models. Thermodynamic parameters such as change in isosteric adsorption enthalpy (ΔH)y and isosteric adsorption entropy (ΔS)y were also determined to 40.8 kJ and 0.141 kJ, respectively. It was concluded that the adsorption of methylene blue increases with increasing temperature. BET model fitting indicates that the hydrophobic interactions between the dye and the produced active carbon at the first layer and the dipole-dipole interactions between methylene blue molecules and the adsorbed molecules at the secondary layer predominate. To investigate the adsorptive characteristics of the produced active carbon, porosity and BET surface area measurements were made.

    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus1OpenAlex1
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  • BildiriAçık Erişim2011
    Mathematics teachers' views about measurement and evaluation dimension of new Turkish geometry curriculum

    Yilmaz, Gül Kaleli; Alkan, Sevilay; Baran, Demet; Elmas, Hülya; Güven, Bülent

    The aim of this study is to investigate mathematics teachers' views about measurement-evaluation dimension of new Turkish geometry curriculum. With this aim, 15 mathematics teachers who are selected from Artvin, Bayburt, Rize and Trabzon were carried out semi-structured interview. As a result, it was seen that teachers in our samples tend to apply traditional measurement and evaluation approach as they find the new measurement-evaluation dimension difficult and uneasy using the tools and methods. And the teachers are not aware of which tools are to be used in alternative measurement and evaluation approach or they do not know how to use it. Also, there are teachers who have negative views about new approach. These teachers have stated the main issue occurs due to time limitations, crowded classes, lack of tools and materials and density of class hours.

    • SDG 4 · Nitelikli Eğitim
    AtıfScopus1WoS1OpenAlex3
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  • BildiriAçık Erişim2011
    Primary school teachers of instructional technologies self-efficacy levels

    Yalcin, Sema Altun; Kahraman, Sakip; Yilmaz, Zeynel Abidin

    In this research, the level of primary school teachers self efficacy believes towards instructional technologies is investigated. The research is performed by applying questionnaires to 43 primary school teachers in Erzincan. The questionnaire consists of 28 questions. For the analysis of the research results SPSS program is used, mean and standard deviation for the answers of all lecturers in the research are calculated. Result of this study is concluded that primary school teachers have high self efficacy believe towards instructional technologies. And teachers believe that they have an understanding of how technology can be integrated into regular classroom instructional practices.

    • SDG 4 · Nitelikli Eğitim
    AtıfScopus9OpenAlex17
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  • MakaleAçık Erişim2012Scopus SJRQ1
    Facility layout using weighted association rule-based data mining algorithms: Evaluation with simulation

    Altuntas, Serkan; Selim, Hasan

    Facility layout has considerable effects on the operational productivity and efficiency of a facility because of its direct effect on material handling costs. The objective of this study is to propose new weighted association rule-based data mining approaches for facility layout problem. Classic association rule-based approaches assume that each item has the same level of significance. On the other hand, in weighted association rule-based approaches, each item is assigned a weight according to its significance with respect to some user defined criteria. In this study, different weighted association rule-based data mining approaches, namely MINWAL(O), MINWAL(W), WARM and BWARM, are applied to facility layout problem. To confirm the viability of the proposed approaches, two case studies are presented. The approaches are compared in terms of general performance criteria for the facility layout problems using simulation. This is the first study that applies weighted association rule-based data mining approaches to facility layout problem. To address the needs in practice, "demand", "part handling factor" and "efficiency of material handling equipment" are used as the weighting criteria. Then, this study differs from the previous works in that it considers the three key location factors together.

    AtıfScopus45WoS28OpenAlex43
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  • MakaleYalnız künye2011Scopus SJRQ1
    A Taguchi approach for optimization of design parameters in a tube with coiled wire inserts

    Gunes, Sibel; Manay, Eyuphan; Senyigit, Ercan; Ozceyhan, Veysel

    This study presents the determination of the optimum values of the design parameters in a tube with equilateral triangular cross-sectioned coiled wire inserts. The effects of the design parameters such as the ratio of the distance between the coiled wire and test tube wall to tube diameter (s/D), pitch ratio (P/D), ratio of the side length of equilateral triangle to tube diameter (a/D) and Reynolds number (Re) on heat transfer and pressure drop were investigated by using Taguchi method. The Nusselt number and friction factor were considered as performance parameters. An L9(34) orthogonal array was chosen as experimental plan. The goal of this study is to reach maximum heat transfer (i.e. Nusselt number) and minimum pressure drop (i.e. friction factor). First of all, each goal was optimized, separately. Then, all the goals were optimized together, considering the priority of the goals. Contribution ratios for each parameter on the heat transfer and pressure drop were determined. Consequently, the optimum results were found to be s/D = 0.0357, P/D = 1, a/D = 0.0714 and Re = 19800.

    AtıfScopus115WoS100OpenAlex113
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  • MakaleYalnız künye2011Scopus SJRQ1
    A new energy saving for the determination of mixing temperature in hot mix asphalts

    Yener, Engin; Hinislioglu, Sinan

    The equi-viscous temperature range of asphalt has long been used in establishing the mixing temperature for mix designs and field production of hot mix asphalt (HMA). However, this method considers only binder viscosity to determine the mixing temperatures of the aggregate and asphalt. It is well known that depending on the gradation of aggregate and the type of plant and the mixing time. The appropriate mixing temperature for the proper coating may be lower than that of the viscosity based method. The excessive temperature causes the possible performance problems related to the hardening of the asphalt binder and increases the energy consumption, the gas emissions and fumes. In this study, a new method for the determination of asphalt-aggregate mixing temperature which considers the mixture properties was introduced to asphalt industry. The mixing temperatures of different nine mixtures were determined by both conventional and the proposed method. The effects of the nominal maximum aggregate size (NMAS), crushed coarse aggregate ratio (CCAR), the type of gradation, and the grade of binder on the mixing temperature were evaluated with an experimental study. Results show that decreasing NMAS, CCAR and increasing the grade of binder decreased the mixing temperature which is needed for proper coating. In addition, results showed that as going away from restricted zone of the Superpave gradation, the needed temperature to coat the aggregates decreased. The proposed method resulted in lower temperatures comparing to the conventional method on an average of 13°C. This means a possible energy saving of 14.3 x 10 9 kcal or 1362000 kg of crude oil in a year in Turkey. As a result, the new method is recommended due to not only the saving in energy but also decreasing the gas emissions and fume, and possible performance benefits.

    AtıfScopus16
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  • MakaleYalnız künye2013Scopus SJRQ2
    The infrared, Raman, NMR and UV spectra, ab initio calculations and spectral assignments of 2-amino-4-chloro-6-methoxypyrimidine

    Cinar, Z.; Karabacak, M.; Cinar, M.; Kurt, M.; Chinna Babu, P.; Sundaraganesan, N.

    (Graph Presented) The 2-amino-4-chloro-6-methoxypyrimidine abbreviated as ACMP have been investigated by both the experimental and theoretical methods; through this work we provide the essential fact about the structural and vibrational insights. The optimized molecular structure, atomic charges, vibrational frequencies and ultraviolet spectral interpretation of ACMP have been studied by performing DFT/B3LYP/6-311++G(df,pd) level of theory. The FT-IR, FT-Raman spectra were recorded in the region 4000-400 cm -1 and 4000-50 cm-1 respectively. The UV absorption spectrum of the compound that dissolved in ethanol and water solution were recorded in the range of 200-400 nm. The scaled wavenumbers are compared with the experimental values. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. Based on the UV spectrum and TD-DFT calculations, the electronic structure and the assignments of the absorption bands were carried out. The 1H, 13C and DEPT 135 nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated using with the Gauge Including Atomic Orbital (GIAO) method and compared with experimental results. Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis were investigated using theoretical calculations.

    AtıfScopus11WoS10OpenAlex11
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  • MakaleAçık Erişim2011Scopus SJRQ1
    Effect of photosonication treatment on inactivation of total and coliform bacteria in milk

    Şengül, Mustafa; Erkaya, Tuba; Başlar, Mehmet; Ertugay, M. Fatih

    The combined effect of simultaneously applied acoustic energy and ultraviolet irradiation (UV-C), named photosonication, on the population reduction of total and coliform bacteria in raw milk was investigated. Photosonication was carried out at 100% (120 μm; 240 W) amplitude of ultrasound accompanied by UV light of 13.2 W cm-2 while sonication was carried out at 100% amplitude without UV light. An ultrasonic processor (400 W and 24 kHz with a 22 mm diameter probe) and 3 ultraviolet lamps (4400 μW cm-2 per lamp) were used. The exposure time was 15 min for all treatment, and samples were taken after 0, 3, 6, 9, 12 and 15 min. Thermal treatment (at 65 °C for 30 min) achieved a 3.29 log and 5.31 log-reduction for total and coliform bacteria, respectively. However, the reduction achieved was 4.79 log cfu mL-1 and 5.31 log cfu mL-1 for total and coliform bacteria, respectively, in photosonication while 1.31 log cfu mL-1 and 4.01 log cfu mL-1 for total and coliform bacteria, respectively in sonication. During photosonication, UV light contributed to an increase of lethality.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    • SDG 6 · Temiz Su ve Sanitasyon
    AtıfScopus33WoS32OpenAlex39
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  • MakaleYalnız künye2011Scopus SJRQ1
    The investigating high school students' learning styles with respect to the different variables: A sample from Turkey

    Metin, Mustafa; Yilmaz, Gul Kaleli; Birisci, Salih; Coskun, Kerem

    The aim of this study is to investigate high school students' learning styles in terms of gender, grade level, type of school, graduation type of mother and father variables. The study was carried out at spring semester of 2010 with 660 high school students who were chosen as a sample from the cities of Artvin and Trabzon, in Turkey. "Kolb Learning Style Inventory" was used as a data collection tool. The inventory was used to determinate the students' learning styles as divergent, assimilator, convergent, and accommodator and the information sheet for demographic factors such as gender, grade level, school type, education of mother and father was used to collect information from students. The data were analyzed by using frequency, percent value, mean scores, standard deviation, independent samples t-test and one-way ANOVA. The results show that the dominant learning style among the students is accommodator and it is followed by divergent learning style. There was not significantly difference between students' learning style and gender except for "Active Experimentation (AE) and AE-RO", grade level "except for Concrete Experience (CE)", school type, education of mother "expert for Reflective Observation (RO)" and education of father.

    AtıfScopus13
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  • MakaleYalnız künye2010Scopus SJRQ1
    Photodimerizations of hydroxy- and benzoylated 4-azachalcones and quantum chemical investigation of the reactions

    Yaşar, Ahmet; YaylI, Nuran; Usta, Asu; YaylI, Nurettin

    Photodimerization reactions of compounds 4-6 gave four new cyclobutane-containing compounds (7-9) with full control over the stereochemistry at the four stereogenic centers. These new cyclobutane- containing compounds had β-truxinic (7a), δ-truxinic (7b and 9), and ε-truxillic (8) structures. However, o-, m-, and p-hydroxy 4-azachalcones (1-3) did not give photochemical cyclization products under any conditions (in solvent or in their solid or molten states). Experimental data suggested the possibility of frontier orbital control over stereochemical behavior, so some theoretical calculations were performed. Full geometrical optimization of compounds 1-9 was performed via DFT B3LYP/6-31+G**, and their electronic structures were also investigated. The geometries of the singlet and triplet states were initially optimized by density functional theory (DFT) and the configuration interaction singles (CIS) B3LYP/3-21 +G**level. An additional calculation was performed for the triplet state using the ground-state geometry. The possible photochemical dimerization products of compounds 7-9 (a-g) and the intrinsic reaction coordinates (IRCs) of the reactions of compounds 4-6 were calculated theoretically by the DFT/3-21+G**method. The configurations (reactant, transition state, product, and reaction pathway) corresponding to the stationary points (minima or saddle points) were determined. The intrinsic reaction coordinates were followed to verify the energy profiles that connect each TS to the appropriate local minimum. The dimeric products expected from the calculations coincided with the dimers produced experimentally.

    AtıfScopus4WoS3OpenAlex2
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  • MakaleYalnız künye2011Scopus SJRQ1
    Waste utilization: The removal of textile dye (Bomaplex Red CR-L) from aqueous solution on sludge waste from electrocoagulation as adsorbent

    Yilmaz, Alper Erdem; Boncukcuoglu, Recep; Kocakerim, Muhtar; Karakas, Ibrahim Hakki

    The potential of removing Bomaplex Red CR-L dye from electro coagulation sludge has been investigated for different Bomaplex Red CR-L concentrations with varying adsorbent amount, temperature, pH and stirrer speed. Removal of Bomaplex Red CR-L is found to be high at lower pH values. The maximum adsorption of the dye has been achieved in aqueous solutions using 0.5g of calcinated sludge from electro coagulation at a pH of 2.0 within 20min. The Langmuir and Freundlich isotherm models were tested and it was found that the Langmuir equation was fitted better than the Freundlich equation. Maximum adsorption capacity (q m) was calculated as 192.31mg g -1 at 333K. In addition, the adsorption data obtained at various temperatures were successfully applied to pseudo first-order, pseudo second-order and intraparticle diffusion models. The rates of adsorption were found to conform to pseudo second-order kinetics with good correlation (R 2≥0.9997). This study showed that calcinated the sludge from electrocoagulation has a highly adsorbent capacity.

    AtıfScopus62WoS55
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