Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(47)
- Pat, Suat(29)
- Özen, Soner(29)
- Şenay, Volkan(24)
- Korkmaz, Şadan(23)
- Esmer, Yusuf(21)
- Şahin, Engin(21)
- Korkmaz, Özge(20)
- Cuce, Erdem(19)
- Öner, Erdal(18)
- Öztürk, Mesut(18)
- Artar, Musa(17)
- Yilmaz, Mustafa Tahsin(17)
- İspirli, Hümeyra(16)
- Ecem Bayram, Nesrin(15)
- Kaya, Yunus(15)
- Cinar, Mehmet(13)
- Cuce, Pinar Mert(12)
- Kamiloğlu, Aybike(12)
- Kutlu, Naciye(12)
- Mercan, Emin(12)
- Birinci, Ahmet(11)
- Bulut, Mehmet(11)
- Yaylacı, Murat(11)
- Bayram, Ozkan(10)
- Can, Zehra(10)
- Doğan, Zeki(10)
- Kahya, Cem(10)
- Karaali, Rabi(10)
- Pabuçcu, Hakan(10)
- Tosun, Figen Çam(10)
- Özdemir, Akın(10)
- Ayazoglu, Rabil(9)
- Battal, Fetullah(9)
- Bayram, Nesrin Ecem(9)
- Büte, Mustafa(9)
- Ertugrul, Mehmet(9)
- Kadakal, Mahir(9)
- Kaplan, Abdullah(9)
- Sarikaya, İsmail(9)
Yayınlar
- MakaleYalnız künye2017Scopus SJRQ1Antimicrobial and functional properties of lactic acid bacteria isolated from sourdoughs
Demirbaş, Fatmanur; İspirli, Hümeyra; Kurnaz, Asena Ayşe; Yilmaz, Mustafa Tahsin; Dertli, Enes
The technological and functional properties of 15 LAB species previously isolated from sourdough were determined in terms of antifungal and antibacterial activities, production of GABA as a functional component and phytase activity. All sourdough isolates were capable of producing GABA and Weissella paramesenteroides N-7 and Lactobacillus paralimentarius E-106 showed the highest and the lowest production levels as 18,43 mM and 3,39 mM, respectively determined by HPLC analysis. The antifungal activity of these strains were tested against Aspergillus niger and Penicillium chrysogenum and two strains Lactobacillus paraplantarum N-15 and L. paralimentarius E-106 showed significant inhibitory effects to these mould species. Generally, different levels of antibacterial activity of these species were observed against food-borne pathogens but only one strain showed low levels of inhibitory effect to Salmonella typhimurium but not the other strains. The PCR detection of several bacteriocin coding genes revealed that all strains were harboured at least one bacteriocin gene among the tested genes. Finally, all strains showed phytase activity but these activity was dependant on strain specific conditions. This study revealed some important techno-functional properties of sourdough LAB strains which can play crucial roles on sourdough technology.
AtıfScopus73WoS60OpenAlex68
İncele - MakaleYalnız künye2017Scopus SJRQ1Experimental determination of cohesion & internal friction angle on conventional concretes
Pul, Selim; Ghaffari, Amir; Öztekin, Ertekin; Hüsem, Metin; Demir, Serhat
Various failure criterions have been used for the nonlinear analysis of concrete and reinforced concrete structures. To get more accurate results from the analyses, the selected failure criterion must be appropriate with the characteristics of problem and the assumptions made in the criterion should comply with the characteristics of problem. In this study, an experimental investigation was carried out to determine the cohesion (c) and internal friction angle (?) values, which are in the compressive strength range of 14.4 MPa ≤ fcm cube ≤ 47.0 MPa (2.03 ksi ≤ fcm cube ≤ 6.82 ksi) that are used in failure criterions such as Mohr-Coulomb and Drucker-Prager preferred in end unit analyses for concrete and reinforced concrete structures. Tests are performed by using the direct shear test system, which is designed and produced for this study. Finally, cohesion and internal friction angle were determined between 2.94 and 12.34 MPa (0.43 and 1.79 ksi) and 29.8 and 41.7 degrees, respectively.
AtıfScopus44WoS38OpenAlex36İncele - MakaleYalnız künye2017Scopus SJRQ2Existence of one weak solution for p(X)-biharmonic equations involving a concave-convex nonlinearity
Mashiyev, Rabil Ayazoglu; Alisoy, Gülizar; Ekincioglu, Ismail
In the present paper, using variational approach and the theory of the variable exponent Lebesgue spaces, the existence of nontrivial weak solutions to a fourth order elliptic equation involving a p(x)-biharmonic operator and a concave-convex nonlinearity the Navier boundary conditions is obtained.
AtıfScopus10İncele - MakaleYalnız künye2017Scopus SJRQ1Toward cost-effective and energy-efficient heat recovery systems in buildings: Thermal performance monitoring
Cuce, Pinar Mert; Cuce, Erdem
Recent studies show that it is possible to reduce heating or cooling demand of a building as using heat recovery systems. Heat recovery technology is basically utilised to mitigate the heat loss, and hence energy consumption due to HVAC. Within the scope of this study, thermal comfort analyses of a test house integrated with a novel polycarbonate heat exchanger are conducted. At pre and post-retrofit case, temperature, relative humidity and CO2 measurements are carried out for a test period of one week. The results indicate that the internal CO2 concentration is not at desirable range due to lack of ventilation in the test house at the pre-retrofit case. However, following the integration of the novel ventilation system into the test house, CO2 concentration is found to be varying notably from 350 to 400 ppm which corresponds to the actual comfort conditions for indoor environments. It is also concluded from the results that the average relative humidity inside the test house at the post-retrofit case is found to be 57%, which is in the desired range whereas it is considerably high before retrofitting.
AtıfScopus26WoS25OpenAlex33İncele - MakaleYalnız künye2017Scopus SJRQ2Optical and Surface Characteristics of Mg-Doped GaAs Nanocrystalline Thin Film Deposited by Thermionic Vacuum Arc Technique
Pat, Suat; Özen, Soner; Şenay, Volkan; Korkmaz, Şadan
Magnesium (Mg) is the most promising p-type dopant for gallium arsenide (GaAs) semiconductor technology. Mg-doped GaAs nanocrystalline thin film has been deposited at room temperature by the thermionic vacuum arc technique, a rapid deposition method for production of doped GaAs material. The microstructure and surface and optical properties of the deposited sample were investigated by x-ray diffraction analysis, scanning electron microscopy, energy-dispersive x-ray spectroscopy, atomic force microscopy, ultraviolet–visible spectrophotometry, and interferometry. The crystalline direction of the deposited sample was determined to be (220) plane and (331) plane at 44.53° and 72.30°, respectively. The Mg-doped GaAs nanocrystalline sample showed high transmittance.
AtıfScopus19WoS5OpenAlex59İncele - MakaleYalnız künye2017Scopus SJRQ2Highly Enantioselective Production of Chiral Secondary Alcohols Using Lactobacillus paracasei BD101 as a New Whole Cell Biocatalyst and Evaluation of Their Antimicrobial Effects
Yılmaz, Durmuşhan; Şahin, Engin; Dertli, Enes
Chiral secondary alcohols are valuable intermediates for many important enantiopure pharmaceuticals and biologically active molecules. In this work, we studied asymmetric reduction of aromatic ketones to produce the corresponding chiral secondary alcohols using lactic acid bacteria (LAB) as new biocatalysts. Seven LAB strains were screened for their ability to reduce acetophenones to their corresponding alcohols. Among these strains, Lactobacillus paracasei BD101 was found to be the most successful at reducing the ketones to the corresponding alcohols. The reaction conditions were further systematically optimized for this strain and high enantioselectivity (99%) and very good yields were obtained. These secondary alcohols were further tested for their antimicrobial activities against important pathogens and significant levels of antimicrobial activities were observed although these activities were altered depending on the secondary alcohols as well as their enantiomeric properties. The current methodology demonstrates a promising and alternative green approach for the synthesis of chiral secondary alcohols of biological importance in a cheap, mild, and environmentally useful process.
AtıfScopus41WoS35OpenAlex38
İncele - MakaleYalnız künye2017Scopus SJRQ2Investigation on the physical properties of C-doped ZnO thin films deposited by the thermionic vacuum arc
Mohammadigharehbagh, Reza; Özen, Soner; Hakan Yudar, H.; Şenay, Volkan; Pat, Suat; Korkmaz, Şadan
The aim of this study is to determine some physical properties of C-doped ZnO coated on a glass substrate by using the thermionic vacuum arc method. The produced C-doped ZnO thin film is characterized by using several analysis techniques. The produced thin film has a cubic crystal structure, high transmittance in the visible region, symmetrical surface distribution, and optical band gap energy of 3.34 eV. According to the XRD analysis of the produced thin film, it is a fullerene (C60)-doped polycrystalline ZnO. Hardness value and Young's modulus value were determined as 8 GPa and 140 GPa, respectively. These physical properties are adequate for future transparent electrode applications.
AtıfScopus15WoS15OpenAlex16İncele - MakaleYalnız künye2017Scopus SJRQ4Some physicochemical properties of wild and cultivated pomegranates (Punica granatum L.)
Gozlekci, S.; Ercisli, S.; Choudhary, R.; Cakir, O.; Sagbas, H.I.
The fruits of seven wild grown pomegranate genotypes and well-known cultivar Hicaznar were analysed for several physical (fruit mass, shape index, calyx length, peel yield, peel thickness, aril yield and juice yield) and chemical (soluble solid content, titratable acidity, pH, soluble solid content/acidity, total phenolic content, antioxidant activity and total anthocyanin) properties. There were statistical differences within wild genotypes and also between wild genotypes and cv. Hicaznar in terms of most of the parameters. The average fruit mass ranged from 127-192 g among wild genotypes and cv. Hicaznar had 394 g fruit mass. The wild genotypes, in general, had lower aril and juice yields than cv. Hicaznar. However they have higher total phenolic content and antioxidant activity than cv. Hicaznar.
AtıfScopus1İncele - MakaleYalnız künye2017Scopus SJRQ1Cross-entropy measure on interval neutrosophic sets and its applications in multicriteria decision making
Şahin, Rıdvan
The neutrosophic set model is an important tool for dealing with real scientific and engineering applications because it can handle not only incomplete information but also the inconsistent information and indeterminate information which exist commonly in real situations. In this paper, we firstly propose two practical techniques converting an interval neutrosophic set into a fuzzy set and a single-valued neutrosophic set, respectively. Then, we define the interval neutrosophic cross-entropy in two different ways, which are based on extension of fuzzy cross-entropy and single-valued neutrosophic cross-entropy. Additionally, two multicriteria decision-making methods using the interval neutrosophic cross-entropy between an alternative and the ideal alternative are developed in order to determine the order of the alternatives and choose most preferred one(s). Finally, an illustrative example is presented to verify the proposed methods and to demonstrate their effectiveness and practicality.
AtıfScopus65WoS62OpenAlex72İncele - BildiriYalnız künye2017Influence of ball and powder filling ratios (Jb and fc) on the dry grinding process of calcite
Uçurum, M.; Bayraktar, I.; Ozyurt, M.; Atalay, F.; Torun Bilgic, E.; Karadeniz, M.; Gulsun Kilic, M.; Onel, O.
Turkey has important quantity of industrial minerals and calcite is one of them and is used as filler in the industries such as plastics, rubber, and paint, to gain a variety of features to products. In order to use calcite as filler, some specific properties such as fine product size are required. In the world, conventional ball mill technology is used to obtain calcite with micronized on the industrial scale. In the mill, ball filling ratio (Jb) and powder filling ratio (fc) directly affect product size, energy consumption, and grinding costs. In this study, influence of important operating parameters such as ball and calcite filling ratios (Jb and fc) on the grindability of calcite ore was examined to obtain a fine product (<100 μm) in the conventional ball mill. The batch test results show that the parameters play an important role in the fine grinding process of calcite.
- MakaleYalnız künye2017Scopus SJRQ4The merrifield-simmons indices of 2-methyl alkanes and 1-methyl bicyclo [X.1.0] alkanes
Gültekin, Inci; Sahin, Bünyamin
In this paper the Merrifield-Simmons indices of the 2-methyl alkanes and the 1-methyl bicyclo [X.1.0] alkanes are obtained. After that, the Merrifield-Simmons index of the binary compositions of these molecules which are connected with a single carbon atom are obtained.
- MakaleYalnız künye2017Scopus SJRQ1Noniterative complex permittivity retrieval using calibration-independent waveguide measurements
Hasar, Ugur Cem; Kaya, Yunus
Calibration-independent nonresonant measurements can be employed to eliminate the need for calibration before microwave measurements. These methods generally assume that the location of the sample in its measurement cell is known after the sample is positioned or shifted within the cell and that the length of the measurement cell is known. In addition, in general these methods necessitate some sort of numerical analysis to retrieve the complex permittivity of the sample. In this research paper, we propose a calibration-independent nonresonant waveguide method to first eliminate measurement errors arising from inaccurate knowledge of the location of the sample within its cell (after shifting) and arising from improper knowledge of the length of the measurement cell and second to determine the complex permittivity explicitly. In addition, our proposed method needs scattering parameter measurements from three different measurement configurations – another improvement with respect to a similar calibration-independent method requiring measurements from four different configurations. Furthermore, it does not necessitate that the sample be flushed to the measurement cell. We analyzed repeatability of cell connection and investigated uncertainty in the measurement of complex permittivity for a change in length of the sample and the cell and when air gap present between sample surfaces and guide walls. We validated the proposed method by measuring the complex permittivity of polyethylene sample and distilled water at X-band (8.2–12.4 GHz).
AtıfScopus8WoS8OpenAlex8İncele - MakaleYalnız künye2017Scopus SJRQ1Characterization of lactic acid bacteria from yogurt-like product fermented with pine cone and determination of their role on physicochemical, textural and microbiological properties of product
Sert, Durmuş; Mercan, Emin; Dertli, Enes
The aim of this study was to understand how pine cone (PC) addition could acidify the milk and result in the production of yogurt. For this purpose, yogurts were produced with three different pine cones which were classified according to collection period; PC-1 (October), PC-2 (November) and PC-3 (December). Physicochemical, textural and microbiological properties were determined as quality criteria on the yogurt samples. Importantly, Lactic Acid Bacteria (LAB) were isolated and identified from yogurt samples. 26 of 80 yogurt isolates were identified. The incubation time of yogurts until the pH reached 4.6–4.7 was ∼3.5–4 h at 45 °C. Textural properties of yogurt PC-3 increased as compared to PC-1 and PC-2 which was found to be related with high LAB numbers in PC-3. Similarly, the highest dry matter, water holding capacity, acidity values were determined in the yogurt PC-3 whereas PC-1 had the lowest values. The lowest pH value was found in yogurt PC-3 related to LAB counts. Lactobacillus spp. and Streptococcus spp. counts of yogurts ranged between 5.95-6.82 and 6.32–6.99 log cfu/g, respectively. Also, LAB species were identified as Streptococcus thermophilus and Lactobacillus plantarum in all yogurt samples showing that pine cones somehow harbour the yogurt starters.
AtıfScopus60WoS58OpenAlex59İncele - MakaleYalnız künye2017Scopus SJRQ2Optimum design of steel bridges including corrosion effect using TLBO
Artar, Musa; Catar, Recep; Daloglu, Ayse T.
This study presents optimum design of plane steel bridges considering corrosion effect by using teaching-learning based optimization (TLBO) method. Optimum solutions of three different bridge problems are linearly carried out including and excluding corrosion effect. The member cross sections are selected from a pre-specified list of 128 W profiles taken from American Institute of Steel Construction (AISC). A computer program is coded in MATLAB to carry out optimum design interacting with SAP2000 using OAPI (Open Application Programming Interface). The stress constraints are incorporated as indicated in AISC Allowable Stress Design (ASD) specifications and also displacement constraints are applied in optimum design. The results obtained from analysis show that the corrosion effect on steel profile surfaces causes a crucial increase on the minimum steel weight of bridges. Moreover, the results show that the method proposed is applicable and robust to reach the destination even for complex problems.
AtıfScopus9WoS9OpenAlex2İncele - MakaleYalnız künye2017Scopus SJRQ1Characterization of functional properties of Enterococcus spp. isolated from Turkish white cheese
İspirli, Hümeyra; Demirbaş, Fatmanur; Dertli, Enes
Enterococcus species was isolated from Turkish white cheese and genotypic characterization of these isolates revealed the presence of 12 distinct strains belonging to 5 different species: Enterococcus faecium, E. faecalis, E. durans, E. gallinarum and E. italicus. All strains showed good survival ability under bile salt conditions. The antibiotic resistance of these strains was low but two strains showed high levels of resistance including resistance to vancomycin. PCR detection of virulence determinant in these isolates revealed that cheese isolate enterococci contained virulence genes common in gut and food originated enterococci and importantly two strains harboured cylB gene related to cytolysin metabolism. No complete hemolytic activity was observed for Enterococcus strains but partial hemolytic activity was observed 8 out of 12 strains. Additionally, all strains showed important levels of antimicrobial activity against food-borne pathogens and PCR screening of genes encoding enterocin A and B indicated the presence of enterocin B gene in all tested strains. The antimicrobial activities of the tested strains were lost after proteolytic enzyme treatments but no alteration was observed at different pHs and after heat treatments. In summary, this study reflected characteristics of Enterococcus strains presented in Turkish white cheese in terms of functional and safety perspectives.
AtıfScopus56WoS55OpenAlex68İncele - BildiriYalnız künye2017Effect of chemical dosage on color parameters of hydrophobic calcium carbonate obtained in aqueous solution
Uçurum, M.; Bayraktar, I.; Ozyurt, M.; Atalay, F.; Torun Bilgic, E.; Karadeniz, M.; Gulsun Kilic, M.; Onel, O.
Ultra-fine ground calcium carbonate is widely utilized as a performance mineral in rubber, plastics and paper industries. Both micronized calcium carbonate and a chemical (sodium oleate) treated calcium carbonate products, obtained in the aqueous solution, were used in the experiments. The color property is an important factor that affects the acceptability of the industrial mineral products. The current study describes the relationship between micronized calcium carbonate and coated calcium carbonate on the basis color parameters (L∗, a∗, b∗), whiteness index (WI), saturation index (SI), hue angle (H) and total color difference (ΔE). The results showed that the processing variables (chemical dosage) did not have a significant effect on the color parameters of hydrophobic calcium carbonate products.
- BildiriYalnız künye2017Examination of absorption effects at the Compton to coherent scattering intensities X-rays using Fe-Ca and Fe-Ti binary compounds with WDXRF
Boydaş, Elif; Boydaş, Mustafa Gökalp; Allm, Bünyamin; Akdemir, A.O.; Ekinci, A.; Han, I.; Oztekin, A.; Set, E.; Dadasoglu, F.; Karagoz, K.
Matrix absorption effects have been examined with scattered X-rays by using WDXRF system for Fe-Ca and Fe-Ti binary compounds. Fe as analyte and elements which some of them the K absorption edge just below the characteristic K X-ray energies of the analyte (Fe) as matrix have been chosen. Pure and binary with Fe ratio ranging from 10% to 90% samples were prepared with these elements. These samples have been analyzed in WDXRF system. At the end of measurement, the coherent and Compton scattering X-rays data of Rh Kα X-rays from these samples have been obtained. Matrix absorption effects have been examined by calculating coherent / Compton scattered X-rays intensity ratio.
AtıfScopus3WoS2OpenAlex2İncele - MakaleYalnız künye2017Scopus SJRQ1Continuous and discontinuous contact problem of a functionally graded layer resting on a rigid foundation
Adıyaman, Gökhan; Öner, Erdal; Birinci, Ahmet
In this study, the continuous and discontinuous contact problem of a functionally graded (FG) layer resting on a rigid foundation is considered. The top of the FG layer is subjected to normal tractions over a finite segment. The graded layer is modeled as a non-homogenous medium with a constant Poissons’ ratio and exponentially varying shear modules and density. For continuous contact, the problem was solved analytically using plane elasticity and integral transform techniques. The critical load that causes first separation and contact pressures is investigated for various material properties and loadings. The problem reduced to a singular integral equation using plane elasticity and integral transform techniques in case of discontinuous contact. The obtained singular integral equation is solved numerically using Gauss–Jacobi integral formulation, and an iterative scheme is employed to obtain the correct separation distance. The separation distance and contact pressures between the FG layer and the foundation are analyzed for various material properties and loading. The results are shown in Tables and Figures. It is seen that decreasing stiffness and density at the top of the layer result in an increment in both critical load in case of continuous contact and separation distance in case of discontinuous contact.
AtıfScopus24WoS24OpenAlex26İncele - MakaleYalnız künye2017Scopus SJRQ1Role of airtightness in energy loss from windows: Experimental results from in-situ tests
Cuce, Erdem
The rate of air leakage related energy loss from glazed areas is unequivocal especially in older and poorly installed windows. Therefore, in this research, a comprehensive experimental investigation is done to analyse the importance of air leakage on overall heat transfer coefficient (U-value) of conventional air filled double glazed windows. The tests are conducted in a typical UK dwelling of Nottingham fitted with traditional air filled double glazed windows. One sash of the test window is sealed internally with a special transparent cover to provide excellent airtightness whereas the second window sash is left as it is to represent the ordinary case. The experiments are conducted in April 2016, and dynamic co-heating test methodology is applied to evaluate the rate of enhancement in the U-value of airtight window sash. The results indicate that the airtight window sash has a notably lower U-value compared to the ordinary window sash due to the impact of airtightness and reverse heat flux during noon time owing to the greenhouse effect between transparent cover and internal glazing. The overall U-value of ordinary window sash is found to be 2.67 W/m2K, whereas it is 1.79 W/m2K for airtight window sash. It is observed that about 33% of reduction in heat losses can be achieved via airtight windows.
AtıfScopus60WoS59OpenAlex75İncele - BildiriYayıncıda açık erişim2017Thermal and Acoustic Properties of Aerogels: Preliminary Investigation of the Influence of Granule Size
Moretti, Elisa; Merli, Francesca; Cuce, Erdem; Buratti, Cinzia; Capozzoli, A.; Serra, V.; Howlett, R.
The influence of granules size in silica aerogels is experimentally investigated in terms of thermal and acoustic performance characteristics. The transmission loss (TL) is measured at normal incidence in a traditional impedance tube, whereas the thermal conductivity (λ) is evaluated using a Hot Plate apparatus, setting up an appropriate methodology, due to the nature of the sample. The results reveal that the small granules (granules size in the 0.01-1.2 mm range), which have the highest density, have the best performance both in terms of thermal and acoustic properties. Depending on the granules size, λ varies in 19-22 mW/mK range at 10°C, whereas a TL equal to 13 dB at about 6400 Hz for 20 mm thickness is obtained for small granules.
AtıfScopus58WoS46OpenAlex63İncele