Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(24)
- Cuce, Erdem(18)
- İspirli, Hümeyra(14)
- Cuce, Pinar Mert(13)
- Alım, Bünyamin(12)
- Mercan, Emin(12)
- Sert, Durmuş(12)
- Şenay, Volkan(12)
- Tozlu, Alperen(11)
- Artar, Musa(10)
- Korkmaz, Şadan(10)
- Pat, Suat(10)
- Yilmaz, Mustafa Tahsin(10)
- Özen, Soner(10)
- Gökçe, H.S.(9)
- Sagdic, Osman(9)
- Şakar, Erdem(9)
- Bayram, Ozkan(8)
- Demirtas, M.(8)
- Purcek, G.(8)
- Ergün, Mustafa(7)
- Yanar, H.(7)
- Demir, Lütfü(6)
- Taylan, Osman(6)
- Abdioglu, M.(5)
- Abdioglu, Murat(5)
- Alim, Bünyamin(5)
- Carbas, Serdar(5)
- Guclu, Tamer(5)
- Gökçe, H. Süleyman(5)
- Sayyed, M.I.(5)
- Han, İbrahim(4)
- Ozturk, K.(4)
- Zhang, Z.F.(4)
- Zhang, Z.J.(4)
- Özahi, Emrah(4)
- Şahin, Engin(4)
- Abusoglu, Aysegul(3)
- Andiç-Çakır, Özge(3)
- Baltakesmez, Ali(3)
Yayınlar
- MakaleYalnız künye2019Scopus SJRQ1A study on 3D graphene synthesized directly on Glass/FTO substrates: Its Raman mapping and optical properties
Bayram, Ozkan
In this study, vertically oriented (3D) graphene nanostructures (VGN) were obtained on Glass and Fluorine doped tin oxide (FTO) substrates at relatively low temperatures (approaximatelly at 400 °C) by using plasma enhanced chemical vapor deposition (PECVD) technique. VGNs were characterized using Raman, Uv–Vis and SEM spectroscopies, respectively. Raman spectroscopy showed that growth temperature significantly affected VGN formation and film quality. The layer structures of these VGNs were also confirmed by Raman mapping. The most important data obtained from this study is that although the applied radio frequency (RF) power is the same, the growth temperature significantly affects the graphene formation and morphologies. This was attributed to the fact that CH4 decomposition was very difficult at low temperatures. The optical transmittance of VGNs ranged from 50% to 95% (at 550 nm wavelength) and their electrical conductivity was also determined to be between 5.94 kohm/sqr and 11.2 kohm/sqr. The electrical and optical properties of VGNs, which have a large surface area, indicated that they may be an alternative material for sensor, solar cell and supercapacitor applications.
AtıfScopus19WoS18OpenAlex20
İncele - MakaleAçık Erişim2018Scopus SJRQ1Thermoeconomic multi-objective optimization of an organic Rankine cycle (ORC) adapted to an existing solid waste power plant
Özahi, Emrah; Tozlu, Alperen; Abuşoğlu, Ayşegül
In this paper, thermodynamic and thermoeconomic analyses, and also optimization of an organic Rankine cycle (ORC) were performed. The system was adapted to an existing solid waste power plant with a 5.66 MW installed power capacity in order to produce additional power from the exhaust gas. The actual operating data of the plant were utilized during all stages of the analyses. The originality of this paper is based on the analysis of the possibility of the energy conversion of an exhaust gas with a temperature of 566 & #x000B0;C into the electricity by utilizing an ORC system in the concept of waste-to-energy. Four different working fluids: toluene, octamethyltrisiloxane (MDM), octamethyl cyclotetrasiloxane (D4) and n-decane were considered and analyzed for the current system. This is also another novelty of this study due to lack of such a study, in the open literature, that deals with an ORC utilized for a typical municipal solid waste power plant. According to the thermoeconomic analyses, toluene was found to be the optimum working fluid with the maximum power output of 584.6 kW and the exergy efficiency of 15.69%. The optimization of the cycle was performed by using the non-dominated sorting genetic algorithm method (NSGA-II) in MATLAB software environment. The optimization results were compared and the deviations of the net power output and the total cost rate were evaluated as & #x2212;5.89%, & #x2212;3.51 & #x00024;/h for toluene; 0.96%, & #x2212;3.60 & #x00024;/h for MDM; 8.45%, & #x2212;2.04 & #x00024;/h for D4 and 2.00%, & #x2212;5.54 & #x00024;/h for n-decane, respectively.
AtıfScopus87WoS80OpenAlex88İncele - MakaleAçık Erişim2018Scopus SJRQ1Optimization of reactive powder concrete by means of barite aggregate for both neutrons and gamma rays
Gökçe, H. Süleyman; Yalçınkaya, Çağlar; Tuyan, Murat
High performance concrete has been often preferred in special engineering structures and in challenging composites products. Researchers have recently focused on the radiation shielding characteristics of these type concrete mixtures due to rising nuclear industry in the developing world. In the study, performance of reactive powder concrete was researched with regard to gamma-ray and neutron attenuation when its normal weight aggregate replaced with heavyweight aggregate (barite). For this purpose, reactive powder concrete mixtures were prepared 100% quartz aggregate, 100% barite aggregate and their blending 50–50%, by volume. Some physical and mechanical characteristics such as density, compressive strength, fracture energy, flexural strength and modulus of elasticity of the mixtures were determined. Gamma-ray attenuation coefficients and transmission thickness values were theoretically established for commonly known gamma energies (661.7, 1173.2 and 1332.5 keV). Optimization of the reactive powder mixtures was performed for both neutron and gamma-ray attenuation at 8 MeV. As a result, barite significantly increased the gamma-ray attenuation coefficients of reactive powder concrete. The mechanical performance of reactive powder concrete, however, was markedly reduced as a result of barite substitution. Replacement of quartz by barite aggregate has a more adverse impact on flexural strength than that of compressive strength. A mix that contains 40% barite aggregate of total aggregate volume was found as an optimum RPC mixture for simultaneously shielding neutrons and gamma rays.
AtıfScopus138WoS126OpenAlex141İncele - MakaleAçık Erişim2018Scopus SJRQ1Structural analysis of the α-D-glucan produced by the sourdough isolate Lactobacillus brevis E25
Dertli, Enes; Colquhoun, Ian J.; Côté, Gregory L.; Le Gall, Gwénaëlle; Narbad, Arjan
Cereal-associated Lactic Acid Bacteria (LAB) are well known for homopolymeric exopolysaccharide (EPS) production. Herein, the structure of an EPS isolated from sourdough isolate Lactobacillus brevis E25 was determined. A modified BHI medium was used for production of EPS-E25 in order to eliminate potential contaminants. Analysis of sugar monomers in EPS revealed that glucose was the only sugar present. Structural characterisation of EPS by NMR and methylation analysis revealed that E25 produced a highly branched α-glucan with (α1 → 3) and (α1 → 6) glycosidic linkages, and was similar in structure to a previously reported EPS from Lactobacillus reuteri 180. The 1H and 13C NMR data were contrasted with newly recorded data for known polysaccharides (alternan, commercial dextran) which also contain α-(1,3,6)Glc branch points. It was found in both E25 EPS and alternan that NMR parameters could be used to distinguish glucose residues that had the same substitution pattern but occupied different positions in the structure.
AtıfScopus78WoS73OpenAlex80
İncele - MakaleAçık Erişim2018Scopus SJRQ1Investigation of seismic performance of in-plane aligned masonry panels strengthened with Carbon Fiber Reinforced Polymer
Can, Ömer
Masonry structures are economical, easy to construct and has important advantages such as the use of natural materials. In Turkey, these structures have been heavily built especially with traditional construction methods and nowadays they are popular as well. Therefore, the reinforcement of masonry structures and seismic safety are of paramount importance. Masonry walls are not naturally stable and cannot be considered as homogeneous structures so it is difficult to predict their behavior under load by using numerical methods. Supportive framework of the mathematical model and the data of the experimental studies are required. In this study, 36 wall blocks were prepared in 900 × 900 × 200 mm using hollow masonry brick, blend brick and aerated concrete and these blocks are reinforced with Carbon Fiber Reinforced Polymer in both directions by using three different methods. For the analysis of retrofit brick walls produced and reinforced with different materials, ASTM E591 test method was used. At the end of the experiment period; shear strength performances of the reinforcement methods of the elements, their deformation and energy dissipation capacities were evaluated. According to results, maximum shear strength performance was observed at the masonry panel strengthened by two face. Maximum load value was 172.63 Kn. Also maximum dissipation capacity was observed at the masonry wall reinforced with CFRP covered diagonally. Maximum energy dissipation capacity was 317.1 J.
AtıfScopus32WoS26OpenAlex34İncele - MakaleYalnız künye2018Scopus SJRQ1Vibration and stability analysis of functionally graded sandwich beams by a multi-layer finite element
Kahya, Volkan; Turan, Muhittin
This paper presents a finite element model based on the first-order shear deformation theory for free vibration and buckling analyses of functionally graded (FG) sandwich beams. The present element has 3 N + 7 degrees-of-freedom for an N-layer beam. Lagrange's equations are employed for derivation of the equations of motion. Two types of FG sandwich beams are considered: (a) Type A with FG faces and homogeneous ceramic core, and (b) Type B with homogeneous ceramic and metal faces and FG core. Natural frequencies and buckling loads are calculated numerically for different boundary conditions, power-law indices, and span-to-height ratios. Accuracy of the present element is demonstrated by comparisons with the results available, and discussions are made on the results given in graphs and tables for the sandwich beams considered.
AtıfScopus89WoS81OpenAlex81İncele - Derleme MakaleAçık Erişim2018Scopus SJRQ1Concentrating photovoltaic thermal (CPVT) collectors and systems: Theory, performance assessment and applications
Daneshazarian, Reza; Cuce, Erdem; Cuce, Pinar Mert; Sher, Farooq
Concentrating photovoltaic thermal (CPVT) collectors and systems are very popular in both domestic and industrial solar energy applications. CPVT collectors provides incomparably greater thermal and electrical outputs compared to stand alone PV or hybrid PVT systems as incoming solar energy is maximised inside the unit via energy-efficient concentrators. Within the scope of this paper, a comprehensive review on CPVT collectors and systems is proposed. For an easier assessment of the findings through state-of-the-art analyses on CPVT collectors, the review is presented in a thematic way. Historical overview of the technology is followed by the detailed description of a CPVT collector with main system elements and thermodynamic performance definitions. The review also covers thermal and electrical performance analysis of CPVT collectors using water or air as working fluid, analytical, numerical, simulation and experimental works for performance evaluation of different design configurations of CPVT systems and qualitative analysis of electrical and thermal energy generation. The impacts of concentrator type and concentration ratio on system efficiency, operating temperature and coefficient of performance (COP) are analysed in detail. It is observed from the findings that CPVT collectors are promising devices in market, and they have a good potential to be competitive with conventional power generation systems in the near future.
AtıfScopus193WoS174OpenAlex214İncele - MakaleYalnız künye2018Scopus SJRQ1The effects on performance, combustion and emission characteristics of DICI engine fuelled with TiO2 nanoparticles addition in diesel/biodiesel/n-butanol blends
Örs, I.; Sarıkoç, S.; Atabani, A.E.; Ünalan, S.; Akansu, S.O.
In this study, waste cooking oil biodiesel was mixed with titanium dioxide (TiO2), a metal-based nano particle, and n-butanol (C4H9OH) along with euro diesel to examine their effects on diesel engines. Various ratio of fuel blends were prepared with TiO2 nano particles-diesel-biodiesel and n-butanol. The tests fuels were euro diesel (D100), biodiesel (B100), B20, B20 + TiO2, B20But10 and B20But10 + TiO2, respectively. Thermo-physical properties such as density, pour point, cloud point, cold filter clogging point, flash point and kinematic viscosity of all test fuels were determined followed by investigating engine performance parameters such as torque, power, fuel consumption and etc. Combustion analysis was also investigated. In addition, the effects on emissions such as CO, CO2, HC, NO and smoke opacity were also carried out. The addition of n-butanol to the fuel blends substantially affected density, kinematic viscosity and cold flow properties, while the addition of TiO2 has not much effect on these properties. For all tested fuels, the maximum brake engine torque and power were recorded at approximately 1400 rpm and 2800 rpm, respectively. The addition of TiO2 increased the brake engine torque and power 10.20% and 9.74% and decreased the brake specific fuel consumption 27.73% and 28.37%, respectively compared to blends without TiO2 additive. TiO2 additive increases the maximum cylinder pressure and heat release rate, as a result improved the engine performance and combustion. The addition of n-butanol in the fuel blend increased the maximum cylinder pressure and heat release rate values in comparison to euro diesel. The results of exhaust emission showed a decrease in CO, HC and smoke opacity emissions, whereas increased CO2 and NO emission, except the use of n-butanol reduced the values of NO emission, in comparison to euro diesel and without TiO2 additive. The results show that biodiesel produced from waste cooking oil, n-butanol and TiO2 additive can be used in diesel engines at certain proportion and that the additive materials improve the combustion characteristics, engine performance and exhaust gas emission.
AtıfScopus231WoS193OpenAlex246İncele - MakaleAçık Erişim2018Scopus SJRQ1Gamma-ray attenuation coefficients and transmission thickness of high consistency heavyweight concrete containing mineral admixture
Gökçe, H.Süleyman; Öztürk, Buket Canbaz; Çam, N.Füsun; Andiç-Çakır, Özge
In the study, high consistency heavyweight concrete mixtures containing barite aggregate were produced by using some common mineral admixtures (viscosity modifier, silica fume and fly ash) at various water/binder ratios and binder contents. Gamma-ray linear attenuation coefficients of the concrete mixtures were determined by using gamma sources of 137Cs and 60Co in NaI(Tl) gamma spectrometry system. The relationship between specimen thickness and transmission of the rays was constituted by emphasizing their mean free path, half-value layer, and tenth-value layer. Moreover, experimental mass attenuation coefficients of the concrete specimens were determined and compared with theoretical mass attenuation coefficients calculated by XCOM software depending on elemental fractions of these concrete in equivalent energies (662 keV, 1173 keV and 1332 keV). As a result, the replacement of the aforementioned admixtures with ordinary cement negatively affected the linear attenuation coefficients of the heavyweight concrete. A relative change of up to 25% was observed between the least and the highest attenuation thickness values at a certain gamma-ray transmission. A good regression relationship has been established between density and linear attenuation coefficients, density and mean free path, and density and half- or tenth-value layers of the heavyweight concrete. Theoretical (XCOM) mass attenuation coefficients were found similar to the experimental mass attenuation coefficients of the heavyweight concretes. Although there is a good linear regression relation between the theoretical and experimental mass attenuation coefficients at 662 keV energy of gamma rays, the relations were disappeared at 1173 and 1332 keV energies of gamma rays.
AtıfScopus185WoS173OpenAlex193İncele - MakaleYalnız künye2018Scopus SJRQ1Influence of high pressure torsion-induced grain refinement and subsequent aging on tribological properties of Cu-Cr-Zr alloy
Purcek, G.; Yanar, H.; Shangina, D.V.; Demirtas, M.; Bochvar, N.R.; Dobatkin, S.V.
Effects of ultrafine grain formation via high pressure torsion (HPT) and precipitation during aging on the microstructure, mechanical and tribological properties of a Cu-Cr-Zr alloy have been investigated systematically. HPT results in the formation of ultrafine-grained (UFG) structure in the alloy with an average grain/subgrain size of 155 nm which leads to remarkable improvement in its hardness and strength along with a reduction in elongation to failure. Aging of UFG alloy brings about further strengthening due to the precipitation. UFG formation by HPT increases substantially the wear resistance of Cu-Cr-Zr alloy and reduces the friction coefficient. The highest wear resistance and the lowest friction coefficient are obtained on the sample processed by HPT and subsequent aging. The dominant wear mechanism of the alloy varies depending on the applied processes. Adhesion with smearing is the predominant wear mechanism for the initial (warm extruded) samples having coarse-grained (CG) structure. UFG samples show less adhesional effect with less smearing, and a higher tendency to the formation of cracks, abrasion and delamination seem to be dominant in those samples. Oxidative wear mechanism is also operative in both CG and UFG alloy samples. It may be concluded from this study that a combined process including UFG formation by HPT and subsequent precipitation by artificial aging provides a simple and effective processing procedure for improving the strength, hardness and wear resistance of Cu–Cr–Zr alloys without modification of the chemical composition.
AtıfScopus96WoS91OpenAlex99İncele - Derleme MakaleYalnız künye2018Scopus SJRQ1Green roofs and facades: A comprehensive review
Besir, Ahmet B.; Cuce, Erdem
Based on United Nations Environment Program (UNEP), building sector accounts for 40% of total energy consumption. In European countries, 36% of total greenhouse gas emissions is attributed to buildings. In this respect, green roofs are considered to be one of the most appropriate sustainable solutions to resolve the urban heat island-related issues. Roofs account for nearly 20–25% of overall urban surface areas. Energy saving, thermal insulation, shading and evapotranspiration features highlight the key role of green roofs in overall thermal performance of buildings and microclimatic conditions of indoor environments. Within the scope of this research, the concept of green roofs and facades is comprehensively analysed in a holistic and thematic way. Following a historical overview of the technology, the research is split into various subfields such as energy saving in buildings through greenery systems, multifunctional thermal benefits including evapotranspiration, thermal insulation, shading and thermal comfort features, evaporative cooling for reducing cooling demand and minimising wind driven convection losses. The results achieved from the literature survey clearly indicate that green roofs and facades are key solutions to mitigate building-related energy consumptions and greenhouse gas emissions. According to the previous works, heat flow through the building roofs in summer can be reduced by approximately 80% via green roofs. The green roofs are reported to consume less energy in the range of 2.2–16.7% than traditional roofs during summer time. A similar tendency is observed for the winter season depending on regional and climatic conditions. The temperature difference between conventional and greens roofs in winter is found to be about 4 °C, which is remarkable. Energy demand of buildings in summer is highly dependent on the plant intensity as it is reported to be 23.6, 12.3 and 8.2 kWh/m2/year for extensive, semi-intensive and intensive greenery surface, respectively. Greenery systems are also capable of providing thermally comfortable indoor and outdoor conditions. It is underlined that the annual average accumulation of CO2 reaches the level of 13.41–97.03 kg carbon/m2 for 98 m2 of vertical greenery system. The results of this research can be useful for dwellers, builders, architects, engineers and policy makers to have a good understanding about the potential of green roofs and facades to mitigate building-related energy consumptions and carbon emissions in a renewable, sustainable, energy-efficient and cost effective way.
AtıfScopus547WoS435OpenAlex617İncele - MakaleYalnız künye2018Scopus SJRQ1High temperature superplasticity and deformation behavior of naturally aged Zn-Al alloys with different phase compositions
Demirtas, M.; Kawasaki, M.; Yanar, H.; Purcek, G.
Two Zn-Al alloys, eutectoid Zn-22Al and dilute Zn-0.3Al, were processed through equal-channel angular pressing (ECAP). The ECAP-processed alloys were subjected to long-term natural aging at room temperature for 120 days in order to investigate the effect of long-term natural aging on high-temperature superplasticity and the deformation behavior of these alloys. The grain size of the Zn-22Al alloy increased from 200 nm after ECAP to 400 nm after the natural aging process. The Zn-0.3Al alloy with a grain size of 1.3 µm after ECAP demonstrated a reasonably stable microstructure with the grain size of ~ 1.7 µm after long-term natural aging. The naturally aged ultrafine-grained (UFG) Zn-22Al alloy showed an excellent superplastic elongation of about 1800% at 200 °C. Grain boundary sliding was determined as the dominant deformation mechanism in this alloy. On the contrary, a considerably low elongation to failure of 230% was recorded in the naturally aged fine-grained (FG) Zn-0.3Al alloy at 150 °C, and dislocation creep was evaluated as the main deformation mechanism for this alloy. Detailed microstructural analyses showed that the FG Zn-0.3Al alloy was exposed to grain boundary corrosion during the natural aging process due to the presence of Al precipitates at grain boundaries whereas such formation was not observed in the UFG Zn-22% Al alloy. Grain boundary sliding was hindered by grain boundary corrosion and the cavity nucleation at the corroded grain boundaries caused a premature failure leading to such a low elongation in the Zn-0.3Al alloy.
AtıfScopus30WoS30OpenAlex33İncele - MakaleYalnız künye2018Scopus SJRQ1Conjugated polythiophene/Ni doped ZnO hetero bilayer nanocomposite thin films: Its structural, optical and photoluminescence properties
Bayram, Ozkan
In this study, synthesis and characterization of plasma polymerized Thiophene/ Nickel doped Zinc Oxide (PTNZO) bilayer nanocomposite films were carried out. Nickel doped zinc oxide (NZO) thin films were obtained by magnetron sputtering technique on glass substrates at 40 W Radio Frequency (RF) power. Plasma polymerized Thiophene (PT) thin films were deposited on the NZO thin films obtained on the glass substrate by Radio Frequency (RF) plasma polymerisation technique. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), FTIR and Photoluminescence (PL) analyzes were performed for the characterization of PTNZO hetero bilayer nanocomposite films. In the XRD spectra of PTNZO bilayer nanocomposite thin films, (002) planes were determined as the most basic peak, and it was determined that the intensity of this peak, changed depending on the RF power of polymer thin films. Optical properties of nanocomposite thin films such as transmittance, absorbance and optical band gap were determined by UV–Vis spectroscopy. Optical band gap for PTNZO nanocomposites were 2.72 eV, 2.34 eV, and 2.45 eV, respectively, with increasing RF power. For NZO thin films, this value is 3.12 eV. The optical band gaps calculated from the absorption and transmittance spectra obtained using UV–visible spectroscopy had a good compatibility with those of the optical band spectra calculated from the PL spectra. The tetragonal wurtzite structure of the NZO thin films was examined by SEM analysis. The grain size of NZO nanostructure was found to be approximately 59 nm.
AtıfScopus9WoS9OpenAlex9İncele - MakaleYalnız künye2018Scopus SJRQ1A new method for determination of dynamic stability of self-consolidating concrete: 3-Compartment sieve test
Gökçe, H. Süleyman; Andiç-Çakır, Özge
There are many standard test methods and applications to determine or estimate the workability of fresh concrete mixtures, most of them are focused on highly flowable concrete mixtures. Due to its high flowability, self-consolidating concrete (SCC) is much more vulnerable to segregation compared to conventional concrete mixtures. Thus, researchers have been working on adopting dynamic and static test methods for determination and improvement of segregation stability of those mixtures. In this study, the different segregation test methods presented in the literature were assessed and a novel method, i.e. 3-compartment sieve test, was introduced. The dynamic stability of fresh self-consolidating concrete mixtures was evaluated by the suggested test method after slump-flow and J-Ring tests. In conclusion, the developed new method is recommended for determination of segregation in SCC due to satisfactory concurrency of results with those of visual stability index test (0.67 ≤ R2 ≤ 0.90) and sieve segregation resistance test (0.83 ≤ R2 ≤ 0.90), respectively.
AtıfScopus23WoS19OpenAlex23İncele - MakaleAçık Erişim2018Scopus SJRQ1Effect of high-pressure homogenisation on viscosity, particle size and microbiological characteristics of skim and whole milk concentrates
Mercan, Emin; Sert, Durmuş; Akın, Nihat
Effect of high-pressure (HPH) homogenisation on milk concentrates were studied. Skim and whole milk concentrates were homogenised at 0–150 and 0–40 MPa, respectively, and viscosity, particle size measurement, microbiological and colour characteristics determined. Up to a pressure of 120 MPa, viscosity of HPH-treated skim milk concentrates (SMC) was proportional to HPH pressure and was lower than that of the control (0 MPa). With whole milk concentrates (WMC), HPH decreased viscosity up to a pressure of 20 MPa; above 30 MPa viscosity increased. According to a power law model, both skim and whole milk concentrates showed shear-thinning flow behaviour. HPH at pressures above 120 MPa completely inactivated the microbial load of SMC. Up to a pressure of 50 MPa, HPH decreased the mean particle size (D [3,2]) of SMC; an increasing trend of D [3,2] was observed above 70 MPa. Except at 40 MPa, HPH decreased D [3,2] values of WMC samples.
AtıfScopus52WoS44OpenAlex54İncele - MakaleYalnız künye2018Scopus SJRQ1Thermoeconomic analysis and optimization of a Re-compression supercritical CO2 cycle using waste heat of Gaziantep Municipal Solid Waste Power Plant
Tozlu, Alperen; Abuşoğlu, Ayşegül; Özahi, Emrah
This paper presents thermodynamic and thermoeconomic analyses as well as optimization of a re-compression supercritical CO2 cycle. A gas turbine cycle (GT) is adapted as a model to an existing plant to generate additional power in Gaziantep Municipal Solid Waste Power Plant (GMSWPP). The total capital cost rate and total cost rate of the GT cycle are found to be 20.47 $/h and 77.14 $/h, respectively utilizing SPECO by using the exhaust gas of 16 kg/s with 1.9 bar and 566.7 °c. The net power, the energy and exergy efficiencies, the total cost and the total capital cost rates of the GT cycle are optimized by +1.73%, +3.21%, +2.45%, −1.11% and −1.64%, respectively using NSGA-II in MATLAB in the range of 2.5≤PR≤4, 200≤P6≤216, 16≤T0≤23 and 9.1≤LMTD≤12.9. This paper provides an originality such that optimization as well as thermodynamic and thermoeconomic analyses is performed simultaneously for an existing MSW power plant, which can be stressed that there are scarce amounts of studies related on this field. Moreover, as another novelty, it can be emphasized that net power output of such like plants which have similar capacity can be improved using the developed model and NSGA-II optimization method.
AtıfScopus47WoS43OpenAlex48İncele - MakaleAçık Erişim2018Scopus SJRQ1A novel strategy for probiotic bacteria: Ensuring microbial stability of fish fillets using characterized probiotic bacteria-loaded nanofibers
Ceylan, Zafer; Meral, Raciye; Karakaş, Canan Yağmur; Dertli, Enes; Yilmaz, Mustafa Tahsin
Nanoencapsulation of probiotic bacteria (L. rhamnosus) into poly(vinyl alcohol) & sodium alginate-based nanofibers (VSPBe) and also the production of poly(vinyl alcohol) & sodium alginate-based nanofibers (VS) were successfully obtained. VSPBe and VS nanofibers were used to limit the Total Mesophilic Aerobic Bacteria (TMABc), Psychrophilic Bacteria (TPBc) and also Yeast and Mold count (TYMc) growth in the fish fillet. Dispersion stability (ζ potential −6.29 mV and −7.74 mV, for VS and VSPBe, respectively), thermal decomposition (a reduction in mass of VS and VSPBe at temperatures 50 °C, corresponding to <5% and >5%, respectively) and morphological properties of nanofibers (diameters between 60 nm and 580 nm) were revealed by characterization analysis. Microbiological tests demonstrated that VS and VSPBe were effectively delayed the TMABc and TPBc growth in fish fillets up to 38%. However, the antimicrobial effects of nanofibers were not pronounced for TYM growth in the fish fillet. The viability of probiotic bacteria could be provided after electrospinning process and the use of L. rhamnosus-loaded nanofibers for delaying microbial growth in the fish fillets could be evaluated as a natural/novel technique.
AtıfScopus108WoS95OpenAlex108İncele - MakaleAçık Erişim2018Scopus SJRQ2A study on the optical, chemical and dielectric properties of PPCIN thin films derived from essential oil compounds using RF plasma polymerisation technique
Bayram, Ozkan; Simsek, Onder
Polymer-based nanostructured films were produced on various substrates using Radio Frequency (RF) plasma polymerization technique from Cinnamaldehyde monomer which is an organic compound. To fabricate polymer thin film, the pressure, the deposition time and RF power were set to 480 mTorr, 30 min and 15, 20 and 30 W, respectively. The effect of RF power on the optical, morphological and chemical properties of thin films were investigated. The optical, morphological and chemical properties were determined by UV–Vis spectroscopy, Atomic Force Microscopy (AFM) and FTIR spectroscopy, respectively. The average surface roughness of thin films was detected as 5.7 nm, 3.9 nm and 11.7 nm using AFM depending on the increase in RF power. Using FTIR spectroscopy, the chemical structure of the polymer thin films was compared with that of the monomer material, and it was found that the majority of the functional groups belonging to the monomers also appeared in the thin films. Optical band gap of thin films increased with RF power and these values were determined as 2.83 eV, 3.05 eV and 2.98 eV, respectively. The extinction coefficients and refractive indices of the thin films were measured at 500 nm between 0.00183–0.00522 and 2.40–2.78, respectively.
AtıfScopus14WoS14OpenAlex16İncele - MakaleAçık Erişim2017Scopus SJRQ2L-shell differential cross-section and alignment of uranium at 59.54-keV photon energy
Akkuş, Tuba; Alım, Bünyamin; Yılmaz, Demet; Şahin, Yusuf
L X-ray differential cross-sections of uranium were calculated at several polar scattering angles (85°, 95°, 105°, 115°, 125°, and 135°) at 59.54-keV photon energy by using a Si(Li) detector. We observed that Ll and Lα X-rays were dependent on the polar scattering angle, whereas Lβ and Lγ X-rays were independent of the polar scattering angle. Therefore, the anisotropy parameters for Ll and Lα X-rays were obtained using the intensity ratios of Ll to Lγ X-rays and of Lα to Lγ X-rays to reduce some systematic errors.
AtıfScopus2WoS2OpenAlex2İncele - MakaleAçık Erişim2017Scopus SJRQ3Asymmetric epoxidation of enones using cumyl hydroperoxide and in situ generated zinc complexes of chiral pyrrolidinyl alcohols
Karaman, Halide Sedef; Kılıç, Hamdullah; Şahin, Engin
The homogeneous asymmetric epoxidation of a range of enones was carried out using cumyl hydroperoxide, diethylzinc, and chiral pyrrolidinyl alcohol-containing ligands to afford the corresponding epoxy ketones with enantioselectivities of ≤97% ee. Examination of the enantioselectivities obtained in the asymmetric epoxidation of enones using a range of chiral ligands indicated that synergy between the sterically bulky bicyclo[2.2.2]octane skeleton and the substituents attached to the carbinol moiety played an important role in determining the reaction enantioselectivity. The position and nature of the substituent on the aromatic ring of the enone also had a pronounced effect on the observed enantioselectivity.
AtıfScopus5WoS5OpenAlex5İncele