Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(17)
- Şahin, Engin(8)
- Bayram, Ozkan(7)
- Esmer, Yusuf(7)
- Degirmenci, Yavuz(6)
- Yilmaz, Mustafa Tahsin(6)
- Dursunoğlu, İsmail(5)
- Göktaş, Bora(5)
- İspirli, Hümeyra(5)
- Şenay, Volkan(5)
- Bulut, Mehmet(4)
- Can, Zehra(4)
- Kaban, Güzin(4)
- Korkmaz, Özge(4)
- Pabuçcu, Hakan(4)
- Sagdic, Osman(4)
- Sefali, Abdurrahman(4)
- Serencam, Hüseyin(4)
- Simsek, Onder(4)
- Taylan, Osman(4)
- Ag, Aliriza(3)
- Bayraktar, Bülent(3)
- Bulut, Ayhan(3)
- Cuce, Erdem(3)
- Dayi, Faruk(3)
- Durmaz, Atakan(3)
- Gökçe, H. Süleyman(3)
- Küçük Demir, Betül(3)
- Mavi, Ahmet(3)
- Ucan, Izzet(3)
- Uçurum, Metin(3)
- Özen, Soner(3)
- Öztürk, Mesut(3)
- Abdioglu, M.(2)
- Acar, Adalet(2)
- Agirman Aydin, Tuba(2)
- Akay, Ebru Çağlayan(2)
- Akkan, Yaşar(2)
- Akkoyunlu, Ebubekir(2)
- Akkuş, Ömer(2)
Yayınlar
- MakaleAçık Erişim2019Scopus SJRQ2Modification of eutectic Al-Si alloys by Sr and CuSn5
Çolak, Murat
Enhanced properties can be achieved in Al-Si alloys by several alloying element additions. Typical modifiers are Na, Sr, and Sb that alters Si into a fibrous structure. Fluidity and mechanical properties increase as well as machinability can be improved. In this work, eutectic Al-Si alloy was modified with Al10Sr, CuSn5, and Al10Sr + CuSn5 master alloys. Microstructural characterization was carried out by optical and scanning electron microscopy. Density and hardness of the samples were measured. Wear tests were carried out. It was found that Sr modified Al12Si revealed better performance than CuSn modified.
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İncele - MakaleAçık Erişim2019Scopus SJRQ1Production of skim milk powder by spray-drying from transglutaminase treated milk concentrates: Effects on physicochemical, powder flow, thermal and microstructural characteristics
Er, Betül; Sert, Durmuş; Mercan, Emin
The effects of transglutaminase (TGase) treatment of skim milk concentrates on physicochemical, powder flow, thermal, microstructural characteristics and protein profiles of skim milk powders (SMP) were investigated. Spray-dried SMP samples produced from milk concentrates were TGase-treated at enzyme concentrations of 0 (control), 0.020% (TG-20), 0.030% (TG-30) and 0.035% (TG-35). Lower particle size values were observed in TGase-treated samples. TGase treatment slightly decreased zeta potential and increased the a* value (redness) of SMPs. Up to a concentration of 0.030%, TGase treatment decreased caking characteristics and increased glass transition temperatures of samples. The TGase treatment above 0.035% significantly decreased cohesion index and compaction coefficient at different speeds. TG-35 showed free flowing flow behaviour depending on the cohesion index, whereas control, TG-20, and TG-30 showed easy flowing behaviour. SDS-PAGE analysis revealed that high molecular mass bands indicated cross-linking in TGase-treated milk powders.
AtıfScopus30WoS24OpenAlex31İncele - EditoryalYalnız künye2019Preface
Akay, Ebru Çağlayan; Korkmaz, Özge
- MakaleAçık Erişim2019Scopus SJRQ3Production of enantiomerically pure (S)-phenyl(pyridin-2-yl)methanol with Lactobacillus paracasei BD101
Şahin, Engin; Serencam, Hüseyin; Dertli, Enes
Asymmetric reduction studies of heteroaryl ketones, including phenyl(pyridin-2-yl)methanone in enantioselective form with biocatalysts are very few, and chiral heteroaryl alcohols have been synthesized generally in the small scale. In this study, seven bacterial strains have been used to produce the (S)-phenyl(pyridin-2-yl)methanol in high enantiomeric excess and yield. Among the tested strains, Lactobacillus paracasei BD101, was found to be the best biocatalyst for the reducing phenyl(pyridin-2-yl)methanone to the (S)-phenyl(pyridin-2-yl)methanol at gram scale. The asymmetric bioreduction conditions were systematically optimized using L. paracasei BD101, which demonstrated excellent enantioselectivity and high level of conversion for the bioreduction reaction. (S)-phenyl(pyridin-2-yl)methanol, which is an analgesic, was produced enantiomerically pure form in the first time on gram scale using a biocatalyst. In total, 5.857 g of (S)-phenyl(pyridin-2-yl)methanol in enantiomerically pure form (>99% enantiomeric excess) was obtained in 52 h with 93% yield using whole cells of L. paracasei BD101. Enantiomerically pure (S)-phenyl (pyridin-2-yl)methanol, which is an analgesic, was first produced in the gram scale using a biocatalyst with excellent ee (>99%) and yield (93%).
AtıfScopus9WoS7OpenAlex9İncele - MakaleAçık Erişim2019Scopus SJRQ1Response surface optimization for a nonlinearly constrained irregular experimental design space
Ozdemir, Akin; Cho, Byung Rae
Finding optimum conditions for process factors in an engineering optimization problem with response surface functions requires structured data collection using experimental design. When the experimental design space is constrained owing to external factors, its design space may form an asymmetrical and irregular shape and thus standard experimental design methods become ineffective. Computer-generated optimal designs, such as D-optimal designs, provide alternatives. While several iterative exchange algorithms for D-optimal designs are available for a linearly constrained irregular design space, it has not been clearly understood how D-optimal design points need to be generated when the design space is nonlinearly constrained and how response surface models are optimized. This article proposes an algorithm for generating the D-optimal design points that satisfy both feasibility and optimality conditions by using piecewise linear functions on the design space. The D-optimality-based response surface design models are proposed and optimization procedures are then analysed.
AtıfScopus18WoS13OpenAlex16İncele - BildiriAçık Erişim2019Tracking particle near a flat surface in digital video microscopy
Yücel, Harun; Akkus, B.; Cakirli Mutlu, R.B.; Gudekli, E.; Kinaci, B.; Guzelcimen, F.; Susoy Dogan, G.; Ozturk, F.C.; Ertoprak, A.
Digital video microscopy (DVM) is an important tool to obtain quantitative information about underlying physics in colloidal systems. DVM, however, has the overlap problem caused by particle's diffraction pattern when the detected particles are close to contact. This overlapping problem limits the tracking methods in determining accurate particle position that reflects all interactions exerting to particles or objects in colloidal studies. The problem occurs not only between two spherical particles close to each other but also when a spherical particle is close to a rod shaped particle which have a flat surface. In this study, the simulation results on the tracking spherical particle placed near the flat surface of a rod particle in 2D digital video microscopy are reported. This work shows that the overlap problem can be resolved by using a fraction of the intensity distribution of a spherical particle which is close to a flat surface.
- Kitap BölümüYalnız künye2019A panel causality analysis on countries attracting most tourists on the basis of carbon emissions, renewable energy, tourism revenues, and trade openness
Boz, Füsun Çelebi
- MakaleAçık Erişim2019Scopus SJRQ2Effective reduction of graphene oxide using sulfur dioxide-containing chemical compounds
Korucu, H.; Şimşek, B.; Kocakerim, M.M.; Karakaş, I.H.
The success of the graphene oxide reduction process depends on how similar the product is to pristine graphene. Sulfur oxide, which is a significant industrial waste gas, can be used in the reduction of graphene oxide. In this study, the graphene oxide reduction process was performed by using sulfur oxide with sodium tetraborate decahydrate, l-ascorbic acid, ammonium hydroxide, sodium hydroxide, lithium hydroxide, sodium borohydride and sodium thiosulfate. The carbon-to-oxygen atomic ratio and D-to-G peak ratio of the graphene oxide, which represent the degree of reduction, were 2.64–4 and 0.78–1.80 with the use of sulfur oxide, respectively. The sulfur oxide/sodium borohydride mixture increased the carbon-to-oxygen atomic ratio of the graphene oxide to 11.73, while improving the value of the D-to-G peak ratio at 3.14. The reduced graphene oxide with the highest specific heat capacity was obtained using sodium tetraborate decahydrate, with an improvement of 74.54% compared to graphene oxide. The results show that sulfur oxide, which is harmful to the environment and human health, can be utilized in an effective reduction process, together with other reducing chemicals, to obtain an industrially valuable material, such as reduced graphene oxide.
AtıfScopus15WoS14OpenAlex15İncele - MakaleAçık Erişim2019Scopus SJRQ2Optical and surface properties of ZnN thin films manufactured by radio frequency reactive magnetron sputtering
Şenay, Volkan; Özen, Soner; Aydoğmuş, Tuna
ZnN is a relatively new material and its physical properties are not yet well studied. In this research, ZnN thin films having different thickness values were deposited on glass substrates by means of radio frequency (RF) reactive magnetron sputtering technique at room temperature and some physical properties of ZnN thin films were investigated by several techniques. UV–vis spectrophotometer and reflectometer were employed to investigate the optical properties of the produced thin films. The surface properties were investigated by using tensiometer and atomic force microscope (AFM). The effects of film thickness on the optical and surface properties of ZnN thin films were discussed. The refractive index and band gap values were found to be dependent on thickness of ZnN thin films. The AFM investigations indicated that the surfaces of the films are compact and smooth. From the wetting experiments, it was found that the surfaces of the films are hydrophobic and surface free energy values are low as reported in literature.
AtıfScopus5WoS5OpenAlex6İncele - MakaleYalnız künye2019Scopus SJRQ3Synthesis and Biological Evaluation of Novel Tricyclic Pyrrolidinyl (R)-Alcohols and Amines
Şahin, Engin; Kılıç, Hamdullah; Törnük, Fatih; Dertli, Enes
Three new tricyclic pyrrolidinyl alcohols and three tricyclic pyrrolidinyl amines were synthesized, and the antibacterial activities of these compounds were tested against Salmonella enterica subsp. enterica serovar Typhimurium, Escherichia coli O157:H7, Staphylococcus aureus, and Listeria monocytogenes. All tested pyrrolidinyl alcohols and amines showed antibacterial activity to the tested pathogens, but this activity was dependent on the final concentration of the tested compound, and the structure of these compounds were also important for this antibacterial activity. Of the tested compounds, (2R)-2-(octahydro-4,8-ethanocyclohepta[c] pyrrol2(1H)-yl)-2-phenylethanamine (2c) was the most effective compound among the tested pyrrolidinyl alcohols and amines. This study shows a good example of finding new antimicrobials in order to control pathogenic bacteria.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2019Impact of Managers’ Innovation Perception on Innovation Activities and Innovation Strategies in Hotel Businesses
Karakaş, Ayhan; Bilgin, Yusuf; Yildiz, Muhammed Raşit; Bilgin, MH; Danis, H; Demir, E; Can, U
The purpose of this study is to examine the impact of managers’ innovation perceptions on innovation activities and innovation strategies in hotel business. The research also examined the relationship between innovation types applied in hotel businesses and innovation strategies. Quantitative method was used in the research. The universe of the research constitutes hotel businesses operating in the Western Black Sea Region. Survey data were obtained using questionnaire technique. As a result of the analysis, it is determined that the innovation perceptions of the managers of the hotel businesses has an effect on the types of innovations applied in the businesses. Nevertheless, it has been determined that business managers’ perceptions of innovation have no meaningful effect on innovation strategies applied to the business. In other words, it has been reached that the innovation strategies of the businesses are determined by the variables other than the innovation perceptions of the managers. The research also find that there is a relationship between innovation types applied in hotel businesses and innovation strategies.
AtıfScopus2WoS2OpenAlex5İncele - MakaleYalnız künye2019Scopus SJRQ1Optimization of design parameters for heat transfer and friction factor in a heat sink with hollow trapezoidal baffles
Sahin, Bayram; Ates, Ibrahim; Manay, Eyuphan; Bayrakceken, Abdulkadir; Celik, Cafer
The aim of this study is to optimize the design parameters of a heat sink on which hollow trapezoidal baffles are mounted on the bottom surface by using Taguchi experimental-design method. The Nusselt number and the friction factor are considered as performance parameters. An orthogonal array is selected as experimental plan for the six parameters: the corner angle (α), the inclination angle (β), the baffle height (H), the baffle length (L), the baffle width (S) and Reynolds number. First of all, each goal has been optimized, separately. Then, all the goals have been optimized together, considering the priority of the goals. The length of the baffle is found to be the most influential parameter on the friction factor. This can be attributed the enhanced effect of longitudinal vortices with baffle length in flow direction. Likewise, it is demonstrated that the most effective parameter on the heat transfer is Reynolds number. The results show that the baffle width (S) and the corner angle (α) have insignificant effect on Nusselt number. The maximum heat transfer was obtained at Re = 17,000, H = 36 mm, L = 45 mm, S = 26 mm, α = 0°, β = 0°. The inclination angle (β) and the baffle height (H) have nearly no effect on the friction factor. The minimum friction factor was obtained at Re = 17,000, H = 20 mm, L = 25 mm, S = 26 mm, α = 16°, β = 0°. The inclination angle (β) and the baffle height (H) have nearly no effect on the friction factor. It can be concluded that the higher heat transfer rates can be achieved with lower pressure drop penalty with this type of vortex generator in particular configurations.
AtıfScopus31WoS27OpenAlex32İncele - MakaleYalnız künye2019Scopus SJRQ2Expert system application for prioritizing preventive actions for shift work: shift expert
Esen, Hatice; Hatipoğlu, Tuğçen; Cihan, Ahmet; Fiğlali, Nilgün
Introduction. Shift patterns, work hours, work arrangements and worker motivations have increasingly become key factors for job performance. The main objective of this article is to design an expert system that identifies the negative effects of shift work and prioritizes mitigation efforts according to their importance in preventing these negative effects. The proposed expert system will be referred to as the shift expert. Methods. A thorough literature review is conducted to determine the effects of shift work on workers. Our work indicates that shift work is linked to demographic variables, sleepiness and fatigue, health and well-being, and social and domestic conditions. These parameters constitute the sections of a questionnaire designed to focus on 26 important issues related to shift work. The shift expert is then constructed to provide prevention advice at the individual and organizational levels, and it prioritizes this advice using a fuzzy analytic hierarchy process model, which considers comparison matrices provided by users during the prioritization process. An empirical study of 61 workers working on three rotating shifts is performed. After administering the questionnaires, the collected data are analyzed statistically, and then the shift expert produces individual and organizational recommendations for these workers.
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İncele - MakaleYalnız künye2019Scopus SJRQ2An approach to neutrosophic graph theory with applications
Şahin, Rıdvan
Graph theory that can be used to describe the relationships among several individuals has numerous applications in diverse fields such as modern sciences and technology, database theory, data mining, neural networks, expert systems, cluster analysis, control theory, and image capturing. As a generalization of fuzzy set (FS) and intuitionistic fuzzy set (IFS), the concept of neutrosophic set is a more functional tool for handling indeterminate, inconsistent and uncertain information that exist in real life compared to FSs and IFSs. In this paper, we apply the graph theory to the single-valued neutrosophic sets and investigate a new kind of graph structure which is called single-valued neutrosophic graphs and is generalized the results concerning crisp graphs, fuzzy graphs and intuitionistic fuzzy graphs. Then we describe some of their theoretical properties, such as the Cartesian product, composition, union and join. By applying two different procedures to solve single-valued neutrosophic decision-making problems, a neutrosophic graph-based multicriteria decision-making model is developed to consider relationships among the multi-input arguments which cannot be handled well by means of the existing methods. Finally, two illustrative examples are given to demonstrate the applicability, feasibility, effectiveness and advantages of these two proposed approaches.
AtıfScopus38WoS21OpenAlex31İncele - MakaleAçık Erişim2019Scopus SJRQ2Some physical properties of nanostructured Al doped ZnO thin films synthesized by RF magnetron sputtering at room temperature
Şenay, Volkan
In this research, AZO thin films were deposited on glass substrates with 70 W, 100 W and 125 W RF powers at room temperature by RF magnetron sputtering technique. The structural, optical and surface properties of the produced thin films were investigated. According to the obtained results, the investigated thin films had a crystalline structure and they showed high transparency in the visible region. The increase of RF power produced thicker films. Relatively thicker AZO films produced with higher RF power exhibited greater number of interference fringes in the reflectance and transmittance spectra. The refractive index values of the film produced with 125 W RF power were considerably lower than those of the films produced with 70 W and 100 W due to the decreased packing density. The optical energy band gap values of the produced AZO thin films were higher than that of undoped ZnO films. This expansion resulted from the Burstein–Moss effect. However, the band gap energy value as well as the roughness of the film surface decreased like refractive index with an increase in RF power, especially after 100 W. As a result, the values corresponding to the optical and surface properties can be tuned and AZO thin films can be produced by RF magnetron sputtering technique as promising candidates for optoelectronic devices and transparent conductive oxide applications.
AtıfScopus14WoS14OpenAlex13İncele - MakaleAçık Erişim2019Scopus SJRQ3Effects of varying essential oil mixture concentrations applied underconditions of different temperature stress on cardiac markers and other blood parameters
Bayraktar, Bülent; Tekce, E.
Cardiac troponin (cTnI) and erythrocyte distribution width (RDW) have been used as specific markers for the evaluation of cardiac arrhythmias and myocardial diseases. In this experimental study, we aimed to determine the dose-dependent administration of an Essential OilMixture (EOM) (Eucalyptus globulusLabill, Thymus vulgaris, Cymbopogon nardus, and Syzygiumaromaticum) on the serum erythrocyte indices and myocardial damage. We used 400 male, oneday-old, Ross-308 chicks. Each group ((n=8) (22°C Control (C), C+250 mL/1,000 L, C+500 mL/1,000 L, C+750 mL/1,000 L), 36°C (stress control (SC), SC+250 mL/1,000 L, SC+500 mL/1,000 L, SC+750 mL/1,000 L) was further divided into eight groups with 50 animals. Each group of 50 chicks was further subdivided into five groups with 10 animals in each compartment. The results showed that the WBC, RBC, HGB, HCT, RDWSD, RDW-CV, and Lymphocyte decreased in groups without exposure to temperature stress (22ºC) compared to the 22ºC control group; whereas, CnTnI, MCHC, NEUT, and IG (p<0.05) increased compared to the control group. In groups exposed to temperature stress (36ºC), the WBC, HGB, HCT, RDW-SD, and Lymphocyte decreased compared to the control group, but MCH, MCHC, NEUT, and IG increased compared to the control. However, cTnI, CK, creatinine, RBC, and RDW had no effect on CD, MONO, EO, and BASO (p<0.05). EOM mixture had no effect on hematological and biochemical parameters.
AtıfScopus9WoS9OpenAlex9İncele - MakaleYalnız künye2019Scopus SJRQ1Purification and biochemical characterization of a novel copper, zinc superoxide dismutase from liver of camel (Camelus dromedarius): An antioxidant enzyme with unique properties
Chafik, Abdelbasset; Essamadi, Abdelkhalid; Çelik, Safinur Yildirim; Mavi, Ahmet
A novel copper, zinc superoxide dismutase (CuZnSOD) was purified to homogeneity from the liver of an animal well adapted to the stressful living conditions of the desert, the camel (Camelus dromedarius). The biochemical properties of camel liver CuZnSOD were examined. The purified enzyme had a native molecular weight of 28 kDa, as judged by gel filtration chromatography, and showed a single band at 27 kDa on SDS-PAGE, indicating that it is a monomeric protein. Optimal activity of the purified enzyme occurred at 43 °C and pH 6.0, and the activation energy was 1.42 kJ/mol. CuZnSOD activity was strongly inhibited by β-ME, DTT, H 2 O 2 and SDS and slightly inhibited by EDTA, NaN 3 and PMSF. Al 3+ , Ca 2+ , Cd 2+ , Mg 2+ and Zn 2+ stimulated CuZnSOD activity, whereas Ba 2+ , Co 2+ , Fe 2+ and Ni 2+ inhibited it. The purified enzyme contained 0.010 µg of Cu and 0.69 µg of Zn per mg of protein. K m , V max , k cat and k cat /K m values for NBT and riboflavin were 16.27 and 0.16 µM, 20.85 and 21.54 U/mg, 9.65 and 9.97 s −1 , and 0.59 and 62.33 s -1 µM −1 , respectively. Camel liver CuZnSOD exhibited unique biochemical properties compared to those of other CuZnSODs, including lower molecular weight with a monomeric structure, higher optimum temperature, very low E a , very low optimum pH, very low contents of Cu and Zn, and higher affinity, turnover number and catalytic efficiency for riboflavin. These unique properties of camel liver CuZnSOD might be related to the ability of this animal to inhabit stressful desert conditions.
AtıfScopus26WoS23OpenAlex26İncele - MakaleAçık Erişim2019Scopus SJRQ3A study of wild plant species of brassicaceae family in bayburt region of Turkey
Gidik, Betül; Gül, Volkan; Sefali, Abdurrahman
The Brassicaceae (Cruciferae) is one of the most important groups and it has 338 genera and 3709 species around the worldwide. Plant samples of the Brassicaceae family were collected and photographed during the vegetation period of 2017. The plant samples and the photos were taken from their natural habitat between 23 April and 11 August 2017. The locations were determined based on differences in geographical features with variable ecological conditions. 38 genera and 80 species and subspecies were identified from different locations of the study area. Heldreichia bupleurifolia Boiss. subsp. rotundifolia, Aethionema caespitosum, Thlaspi lilacinum, Tchihatchewia isatidea, Bornmuellera cappadocica, Aurinia rupestris subsp. cyclocarpa, Alyssum stylare, Alyssum pseudomouradicum, Alyssum peltarioides Boiss. subsp. peltarioides are endemic taxa for Bayburt.
AtıfScopus6WoS3OpenAlex6İncele - MakaleAçık Erişim2019Scopus SJRQ2Antimony removal from aqueous solutions using magnetic nickel ferrite (NiFe 2 O 4 ) nanoparticles
Karcioğlu Karakaş, Zeynep; Boncukcuoğlu, Recep; Karakaş, İbrahim Hakkı
In this study, magnetic nickel ferrite (NiFe 2 O 4 ) nanoparticles were synthesized via microwave assisted combustion method and these particles were used as adsorbent for antimony removal. The most effective parameters for the removal efficiency are adsorbent dosage and temperature, while the impact of pH is insignificant. In order to determine the most suitable kinetic model, the compatibility of pseudo-first order, pseudo-second order and the intraparticle diffusion model was compared and the most suitable kinetic model was determined to be pseudo-second-order. Langmuir and Freundlich isotherms were assessed and the most suitable isotherm was observed to be Freundlich model.
AtıfScopus6WoS3OpenAlex6İncele - MakaleAçık Erişim2019Scopus SJRQ3Cognitive analysis of constructing algebraic proof processes: A mixed method research *
Öztürk, Mesut; Kaplan, Abdullah
This study aimed in order to investigate cognitive aspects of the processes of constructing algebraic proofs of pre-service and service secondary math teachers. We used explanatory sequential design from mixed research methods in the study. Secondary math teachers working in the province east of Turkey and pre-service secondary math teacher in this province participated to the study. Quantitative data of the study were collected through a “Proving Diagnostic Test” and qualitative data were gathered from the participants through a think aloud protocol. We used two different activity cards that each of them included one algebraic proof question in the think aloud protocol. Quantitative data were analyzed using descriptive and inferential statistics. Content analysis was applied to qualitative data. The study show that the cognitive skills performed by pre-service and service secondary math teachers emerge five categories: read the proposition of the proof, evaluating the correctness, determining strategies, carry out plans and heuristic shortcuts thinking strategy. Eight categories were identified in the theme (context of) of meta-cognitive skills. These categories are: facilitating the operations, questioning, awareness, planning, strategy determination, controlling, correlating, and analogical reasoning.
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