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Öğe A comprehensive review on the usability of black phosphorus in energy and wastewater treatment(Elsevier Inc., 2024) Kaya, Gul; Eskikaya, Ozan; Kucukosman, Ridvan; Ocakoglu, Kasim; Dizge, Nadir; Balakrishnan, Deepanraj; Singh Chohan, JasgurpreetIncreasing population and industrial development brings with it many problems that need to be solved, such as energy production, storage, saving, protection of limited reserves, and environmental pollution. Nanomaterials, which emerged with the introduction of nanotechnology into our lives, play an important role in many areas. The novel two-dimensional nanomaterial black phosphorus (BP) exhibits great potential in photocatalytic applications, energy technologies, and purification with properties such as broad light absorption spectrum, tunable direct band gap, and exceptionally high charge carrier mobility. This review gives a outline of the manufacturing techniques, structural, chemical, electrical and thermal properties of BP. Then, the success of BP derivatives with different dimensions and morphologies in environmental and energy applications is presented by comparing them with previous studies in these fields. The results show that heterojunction structures produced by combining BP with MoS2 and MOFs improve the electrochemical properties of BP, while carbonization processes increase its efficiency in battery and supercapacitor applications. Finally, in this review, a summary of BP's potential future uses, awareness of easy production methods, and its activities in environmental and energy applications are discussed in a broad context. © 2024Öğe An experimental study on droplet-scale combustion and atomization behavior in pure ethanol, methanol, and trimethyl borate, and their blends(Elsevier Sci Ltd, 2024) Degirmenci, Huseyin; Kucukosman, Ridvan; Yontar, Ahmet AlperThe combustion and atomization behavior of pure ethanol (EtOH), methanol (MeOH) and trimethyl borate (TMB) fuels and their blends prepared at 20 wt%, 40 wt%, 60 wt% and 80 wt% ratios were determined by processing videographs recorded with a high-speed camera and temperature data recorded with a thermal camera during droplet-scale combustion experiments performed at atmospheric pressure. EtOH and MeOH are good alternatives for transport due to their high oxygen content and relatively short carbon chains. TMB, an organoboron derivative in the liquid phase, is unique to creating a low-carbon emission and high-energy alternative fuel blend with boron, oxygen, and short carbon chains. This study focuses on the preparation of EtOH, MeOH, and TMB fuels and homogenized fuel mixtures with high energy values and the characterization of their combustion behavior. The experiments were carried out by suspending ethanol-trimethy borate (EtOHTMB) and methanol-trimethyl borate (MeOH-TMB) fuel droplets on SiC wire and igniting them with an electrode producing an arc of 1 ms duration at 20 ms intervals with 6 kV energy. The results showed that EtOH and TMB formed a homogenized fuel mixture at all mixing ratios and the largest and most homogeneous green luminescence flame envelopes (depending on boron oxidation) were formed, indicating BO2 formation in almost all fuel mixtures. On the other hand, the droplets of MeOH-TMB fuel mixtures containing 20 wt%, 40 wt%, and 60 wt% MeOH exhibited the most favorable trend to the D2-law of diameter reduction during combustion. EtOHTMB fuel droplets containing 60 wt% TMB exhibited the highest maximum flame temperature of 631 K. In this study, it has been shown that new-generation hybrid transportation fuels with no phase separation, low ignition delay times despite increased oxygen content, and high calorific value can be produced with hybrid fuel blends to be formed with TMB and alcohols. The results obtained will shed light on the literature for the solution to the problematic combustion characteristics of boron, which is tried to be used in many areas of the transportation industry.Öğe Combustion characteristics of gasoline fuel droplets containing boron-based particles(Elsevier Science Inc, 2023) Kucukosman, Ridvan; Degirmenci, Huseyin; Yontar, Ahmet Alper; Ocakoglu, KasimBoron-based particles are dense energy carriers that are promising for a future carbon-neutral world, to store and transport abundant energy. Although it is prominent as a slurry fuel component in liquid aviation fuels, its effects on the combustion behavior of traditional hydrocarbon fuels used in public or industrial areas have not yet been clarified. In this study, combustion characteristics of gasoline-based fuel droplets containing 86-88%, and 95-97% < 1 mu m amorphous boron, 10 mu m AlB12, 28 - 35 mu m MgB2 particles and 1% oleic acid surfactant. The experimental process was recorded via a high-speed camera and a thermal camera. The results showed that the ignition delay time was reduced in all gasoline-based fuels containing boron-based particles. The fuels with the lowest extinction time were gasoline-based fuel droplets containing AlB 12 particles (similar to 1245 ms). Amorphous boron particles were transported to the flame region more than other particles and caused severe atomization phenomena. The highest maximum flame temperature for gasoline droplets at 2.5% particle load was recorded in high-purity amorphous boron particles with 537 K. At 7.5% particle load, the highest flame temperature and agglomerate temperature were observed at 513 K and 653 K, respectively, in gasoline droplets containing high-purity amorphous boron particles. In electric field tests, the shortest extinction time was detected for gasoline droplets with MgB12. Also, the addition of amorph boron particles into gasoline increase of 4.6% was seen in the flame speed. Droplet diameter regression plots show that particulate gasoline-based fuel droplets exhibit a decreasing trend, mostly following the D-2-law. It has been revealed low-cost amorphous boron derivatives can be an important energy carrier for liquid hydrocarbon fuels. (c) 2023 The Combustion Institute. Published by Elsevier Inc. All rights reserved.Öğe Effects of graphene oxide addition on wear behaviour of composite coatings fabricated by plasma electrolytic oxidation (PEO) on AZ91 magnesium alloy(Taylor & Francis Ltd, 2021) Kucukosman, Ridvan; Sukuroglu, Ebru Emine; Totik, Yasar; Sukuroglu, SuleymanGraphene oxide (GO) integrated composite coatings were deposited on AZ91 magnesium alloys by the PEO (Plasma Electrolytic Oxidation) and the treatment which has a post-PEO hydrothermal process. For the first group samples, PEO was performed in the silicate/phosphate-based electrolyte including 5-10 mu m in size the GO particles synthesized using the Tour Method. For the second group samples, after PEO treatment, the post-PEO hydrothermal process was carried out in the oven in the GO-distilled water mixture containing GO produced with the same protocol. The effects of GO on wear behavior, structural and morphological features of composite coatings were examined with a pin-on-disc tribometer, X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectroscopy, respectively. The results showed that the addition of GO improved significantly the adhesion to the substrate material of composite coatings, increased the coating thickness and hardness. Post-PEO hydrothermal process resulted in the formation of partial a thin solid lubricant GO film on the surface of composite coatings and thus exhibited the best wear and friction resistance.Öğe Effects of Spinel Oxide Combustion Catalysts on the Combustion Behavior and Secondary Atomization Mechanism of Gasoline Droplets(Taylor & Francis Inc, 2025) Kucukosman, Ridvan; Yontar, Ahmet Alper; Unlu, Cumhur Gokhan; Ocakoglu, KasimThe catalytic activity of Mg-based spinel oxide nanoparticles (NPs) on the combustion behavior of gasoline and their effects on the atomization behavior were determined by droplet scale combustion experiments. MgFe2O4, MgCo2O4 and MgMnO3 spinel oxide NPs were produced by the sol-gel technique and doped into gasoline. The particles with the highest surface oxygen were MgCo2O4 and MgFe2O4 NPs, while the NPs with the largest surface area were MgCo2O4 NPs (517.8433 m(2)/g). The size of the flame envelope tends to shrink as the oxygen concentration of the particles rises, but an increase in their surface area tends to shorten ignition delay periods. MgFe2O4 NPs increased the flame temperature by 163 & DEG;C compared to the pure gasoline. While MgFe2O4 and MgMnO3 NPs increased the extinction time of gasoline, MgCo2O4 NPs decreased the severe time by about 75% with the violent micro-explosions they created. In this study, we focused on the production of spinel oxide agents customized for combustion with improved catalytic activity, high flammability, and different component designs, and the results showed that these particles can reduce the soot formation of conventional hydrocarbons.Öğe Electrocombustion Characteristics of Iron Particle-Laden Methanol and Ethanol Droplets in a Direct Current Field(Taylor & Francis Inc, 2024) Kucukosman, Ridvan; Degirmenci, Hueseyin; Yontar, Ahmet AlperThis study investigates the electrocombustion and atomization behavior of single droplets (2.5 wt.% Fe) of ethanol (EtOH) and methanol (MeOH) fuels at the droplet scale. The experiments utilize a system with two opposing plate electrodes of varying distances (200, 150, and 100 mm) and both negative (down arrow) and positive (up arrow) polarizations within a vertical direct current (DC) electric field. The results show that for EtOH and EtOH/Fe droplets, the flame envelope changes to a spherical form at (down arrow) and (up arrow) polarizations at 100 mm plate spacing, while for MeOH and MeOH/Fe droplets, the flame envelope changes to a spherical form at (down arrow) and (up arrow) polarizations at 200, 150 and 100 mm plate spacing. Increasing electric field strength reduced the micro-explosion tendency of Fe particles in the flame region and the micro-explosion intensity of Fe particles was found to be higher in ethanol droplets than in methanol. No systematic relationship could be established between the electric field effect and the presence of Fe particles. The MeOH/Fe/150(up arrow) droplet exhibited the lowest extinction time of 1050 ms. The electric field fundamentally alters the secondary atomization process of the fuel droplets. Notably, the diameter regression of all MeOH-based fuel droplets deviates significantly from a linear relationship. The investigation into the combustion behavior of pure EtOH, MeOH, and their Fe-blended counterparts within an electric field environment suggests that MeOH and MeOH/Fe fuels exhibit superior combustion characteristics. However, further research is necessary to fully elucidate these findings.Öğe Enhancing Droplet Combustion Dynamics in Trimethyl Borate-Based Blends: Exploring Energetic Phenomena(Taylor & Francis Inc, 2024) Yontar, Ahmet Alper; Degirmenci, Hueseyin; Kucukosman, RidvanTrimethyl borate (TMB) is an excellent alternative to alter the combustion of conventional fuels due to the combination of boron, stable methyl groups, and oxygen, which can improve the combustion behavior in many ways compared to alcohols and etheric hydrocarbon structures. In this research, the combustion and energetic phenomena trends of trimethyl borate blends was investigated on a droplet scale. The camera systems were used at the combustion characteristics look at how the size of the droplets, the structure of the flame, and the flame temperature changed over time. The additions of 20%, 40%, 60%, and 80% trimethyl borate fuel to gasoline were tested for their ability to burn. As the amount of TMB increased, high variations in droplet deformation and high breakups from the hemispheric geometry occurred. At this point, changes were observed in droplet shape change independent of mixing ratio. TMB droplet had the highest flame temperature of 600 K and the lowest extinction time of similar to 1270 ms. As the gasoline content of the droplets increased, the droplet flame temperature tended to decrease. Also, the shortest ignition delay time was observed for pure TMB and fuel droplets containing 40%, 60% and 80% TMB (similar to 0.714 ms). HIGHLIGHTS The highest combustion rate constant was observed in trimethyl borate. The amount of TMB raised in the blend raised high droplet deformation and breakups. The droplet deformation amplitude is at the maximum level for 8G2T. The shortest ignition delay time was noticed for the 20% gasoline 80% TMB blend. The high gasoline content in the blends caused micro-explosions were observed.Öğe Experimental Analysis of Flame Dynamics and Combustion Parameters of Fe-Enhanced Diesel Fuel Droplets Under Variable Ionic Effect Intensities(Taylor & Francis Inc, 2025) Degirmenci, Huseyin; Kucukosman, Ridvan; Alper Yontar, AhmetThis study examines the combustion behavior and parameters of hybrid fuels prepared by adding 2.5 wt.% Fe nanoparticles to diesel fuel under electric field strengths of E = 0 V/m, 5 V/m, 6.7 V/m, and 10 V/m. The motivation for this research stems from the urgent need to improve combustion efficiency and reduce emissions in heat engines that rely on diesel fuel. In this context, addressing these challenges through the development of novel system approaches is crucial. Additionally, comprehensive investigation of non-traditional fuels plays a vital role in advancing sustainable energy solutions. With global energy demands increasing and environmental concerns intensifying, the need for more efficient combustion processes has become critical. This study explores how fuel additives and electric field applications can contribute to achieving these goals in an environmentally friendly manner. Focusing on the ionic effect on flame dynamics, key combustion parameters were assessed, including flame shape ratio (FShR), average burn rate constant (BRCA), average burning rate (BRA), average flame propagation speed (FPSA), flame spread rate (FSpR), combustion duration (tcomb), and Damk & ouml;hler number (Da). The results indicate that the strength and direction of the ionic effect significantly affect combustion behavior. Notably, Diesel/200(up arrow) exhibited the highest BRCA, whereas Diesel/100(up arrow) achieved the lowest extinction time; however, it did not reach the expected BRCA due to a lower FShR. In the Diesel + Fe group, Diesel + Fe/100(up arrow) achieved the maximum BRCA. This was due to increased flame dispersion and the influence of a strong ionic effect. Additionally, Diesel/100(up arrow) exhibited the highest, which was consistent with the ionic effect direction. Adding Fe nanoparticles improved combustion dynamics by increasing burn rates and flame propagation speeds, which optimizes energy conversion processes. Reverse ionic effect enhanced combustion processes, positively impacting fuel diffusion. Findings showed that Diesel/100(down arrow), influenced by negatively charged ions, displayed a notable reduction in BRA. This highlights the importance of understanding the complex interaction between ionic effect and combustion behavior, particularly under varying electric field conditions. The addition of 2.5% Fe nanoparticles substantially increased BRA in the diesel+Fe group, with Diesel+Fe/100(up arrow) recording the highest BRA. Furthermore, the addition of Fe particles led to an increase in FPSA, allowing Diesel+Fe to achieve the fastest flame spread rate (FSpR) under strong wind conditions. While Diesel/100(up arrow) showed the lowest Da value, Diesel+Fe/100(up arrow) reached the highest, indicating the pronounced effect of reverse polarity on Da.Öğe Experimental studies on combustion and atomization characteristics of aliphatic and aromatic hydrocarbons droplets(Elsevier Sci Ltd, 2023) Kucukosman, Ridvan; Yontar, Ahmet Alper; Ocakoglu, KasimThis study focused on how the properties of alcohols (ethanol, methanol, n-butanol), ketones (acetone), alkanes (hexane), esters (ethyl acetate), methyl benzenes (toluene), and ethers (diethyl ether) shape individual com-bustion and atomization behaviors. The experimentation conducted at the droplet scale involved suspending fuel droplets on a ceramic wire and subsequently igniting them for analysis. Experiments were recorded with a high-speed camera and a thermal camera with a spectral range of 7.5-14 & mu;m. The results showed that the flame of the oxygenated fuel droplets, unlike non-oxygenated fuels, has a high non-luminous region seen throughout the combustion process. The diameter reduction of the fuel droplets during combustion tended to obey the D2-law. Single and multicomponent fuel droplets are hemispherical for preheating (Stage I) and hemispherical in droplet disruption mode for combustion and droplet diameter decrease (Stage II). Hexane, diethyl ether, and ethyl ac-etate were the fuels that were extinguished in the shortest time among the fuels studied here with extinction times of 1.021 s, 0.925 s, and 0.885 s, respectively. Hexane, diethyl ether, acetone, and diesel droplets had the minimum ignition delay times according to the experimental conditions in this study. In terms of maximum flame temperature, ethyl acetate exhibited the highest value among oxygenated fuel droplets, reaching 155 degrees C, while toluene demonstrated the highest maximum flame temperature of 244 degrees C among all fuel types, including non-oxygenated fuels.Öğe Investigation of In-Vitro Properties of NiTi Alloy After Micro Arc Oxidation(Gazi Univ, 2021) Sukuroglu, Suleyman; Totik, Yapr; Sukuroglu, Ebru Emine; Kucukosman, RidvanAs material science is integrated into medical science as in other fields, the variety, development and usage areas of biomaterials increase. One of the biomaterials in this variety is NiTi alloys. This study was focused on the coating of TiO2 layer by using the method of Micro Ark Oxidation with the aim of the improvement of surface and mechanical properties of Shapedmemory and bio material NiTi alloy. Structural properties of the coatings were analysed by of SEM and XRD. In vitro ability was investigated by soaking the coated NiTi samples in simulated body fluid (SBF) at temperature 37 degrees C for various time periods. After soaking, Ni+2 release was applied to the media where coated and uncoated shape-memory NiTi samples are available, and its control was made by means of ICP-MS device. The results also show that Toxic and carcinogenic effects of Ni+2 release is significantly reduced by the TiO2 coating. Thus, it is observed that the properties that limit the use of NiTi alloys has been substantially fixed by MAO coating. It was found that the bioactive properties of the TiO2 coated NiTi substrate increased by MAO method and at the end of the 72 hour, there was no statistically any cytotoxicity in cell viability compared to the NiTi substrate.Öğe Investigation of wear behavior of graphite additive composite coatings deposited by micro arc oxidation-hydrothermal treatment on AZ91 Mg alloy(Elsevier, 2021) Kucukosman, Ridvan; Sukuroglu, Ebru Emine; Totik, Yasar; Sukuroglu, SuleymanComposite coatings were deposited on AZ91 magnesium alloys by micro arc oxidation (MAO) and the MAO-hydrothermal treatment (HT). The MAO process of Mg alloys was performed in the silicate/phosphate-based electrolyte with graphite particles size of 5-10 and 75 mu m and then the obtained samples were submitted to hydrothermal treatment at 150 degrees C in the graphite-ethanol mixture. The structural and morphological properties of composite coatings were analized X-ray diffraction (XRD) and scanning electron microscopy (SEM). The wear resistance was examined with ball-on-disc tribometer. The addition of graphite to the MAO electrolyte solution increased the coating thicknesses and compactness and the surface morphologies acquired relatively a homogeneous appearance. The coating surfaces were enriched in graphite by HT and the wear test results showed that the wear resistance of the graphite-doped MAO-HT composite coatings was significantly improved.Öğe Nanoparticle additive fuels: Atomization, combustion and fuel characteristics(Elsevier, 2022) Kucukosman, Ridvan; Yontar, Ahmet Alper; Ocakoglu, KasimNanoparticle additive fuels (NAFs) are new generation fuels containing nano-sized functional agents that regulate combustion, atomization, and emission behavior without causing a substantial change in the fluid characteristics of the base fuel. These promising agents for the conservation of limited reserves, reducing energy consumption and pollution, also pave the way for the production of new fuels or the adaptation of conventional fuels to specific operating conditions, even at dilute concentrations. Even so, the combustion kinetics of NAFs with dual-phase structures are different and complex from solid fuels and non-additive liquid fuels. This review highlights the unique potential of NAFs and explains their combustion mechanism. The primary atomization of NAFs sprayed from injection systems is studied. Then, the results of droplet scale tests presented in the literature in recent years are examined and the disruption (atomization), combustion and evaporation behaviors of NAFs are determined. In addition, experimental and numerical evaluations of the combustion of nanoparticles (NPs) in individual and aggregate forms are performed in order to better understand the effect of the size and concentration of used NPs on combustion. The effects of NPs on the performance and emission values of liquid fuels used in public spaces and propulsion systems are determined by evaluating the intermittent and continuous combustion laboratory test results of NAFs. The results showed that the presence of NPs has profound effects on the combustion physics and combustion chemistry of hydrocarbon fuels. While the size and concentration of NPs are responsible for the physics of combustion, the components, catalytic activity, oxygen content, reactivity and calorific value of the NPs are responsible for the combustion chemistry. Spray characteristic tests showed that the optimum NP concentration for NAFs was 0.5 wt%, while the tests on the droplet scale for evaporation and combustion characteristics showed that the optimum particle concentration was 2.0-2.5 wt%. In the tests made for engine performance and emission values, such a result could not be drawn because the critical concentration differs for the dependent variables. However, it has been observed that NPs (Al, B, Fe, Al2O3, Fe2O3, CeO2, ZnO, graphene oxide, etc.) with high calorific value, thermal conductivity, and catalytic activity have significant effects on these parameters.Öğe Synthesis of Rhombic Dodecahedral Cuprous Oxide Nanoparticles and Investigation of Biological Activity(Springer, 2022) Kucukosman, Ridvan; Isik, Zelal; Ozdemir, Sadin; Gonca, Serpil; Ocakoglu, Kasim; Dizge, NadirThe rhombic dodecahedral cuprous oxide (Cu2O) nanoparticles (NPs) were synthesized with the morphology-controlled one-pot solution-phase technique and several biological activities were investigated. The structural and elemental properties of Cu2O NPs were determined by SEM-EDX and XRD. Antioxidant, antimicrobial, DNA interaction, and biofilm inhibition activities were determined by using DPPH radical scavenging and metal chelating, microdilution, agarose gel electrophoresis, and crystal violet methods, respectively. The newly synthesized copper nanoparticle showed excellent DPPH and iron-chelating activities as 100% at 200 mg/L concentration. It showed good DNA cleavage activity at all concentrations. Cu2O NP had good antibacterial activity against all tested microorganisms. Biofilm inhibition percentage of Cu2O NP was determined as 86.3% at 500 mg/L. The cell viability assay demonstrated that the Cu2O NP showed 100% cell viability inhibition at all concentrations. Generally, owing to the biological active nature of the synthesized copper nanoparticle, these synthesized Cu2O NPs can be used as a therapeutic and antioxidant agent.Öğe The Usability of Polymer-Doped Black Phosphorus (BP@PVDF) as a Photocatalyst for Dye Removal in a Photocatalytic System(Springer/Plenum Publishers, 2024) Eskikaya, Ozan; Kucukosman, Ridvan; Ocakoglu, Kasim; Dizge, Nadir; Deepanraj, Balakrishnan; Senthilkumar, NatarajanIt is well known that water with dye content needs to be treated to remove the environmental and health hazards it poses. In this study, the refinability of the photocatalytic treatment process with a photocatalyst containing black phosphorus, which is a popular material recently, was investigated. Black phosphorus (BP) was synthesized directly from red phosphorus at 180 degrees C using the recyclable liquid phase method in an ethylenediamine medium. Microstructural characterization of the samples was carried out by SEM, HR-TEM, BET and XRD techniques. A composite material was synthesized in a polymer-containing solution (Polyvinylidene fluoride; PVDF) to prevent the BP from being easily separated from the water and from being deformed. The obtained polymer-doped BP (BP@PVDF) as a photocatalyst was successfully removed from Methylene Blue (MB) dye in the photocatalytic system. As a result of the photocatalytic experiments with BP@PVDF, the removal efficiency of MB dye (10 ppm) was 93.49% after 1 h of the solution with a pH value of 7 under visible light. In addition, after 10 reuses in reuse experiments, the removal efficiency of the material decreased by 30.25%. Even in this case, 65.83% removal efficiency was obtained even in the 10th reuse of the reused BP@PVDF. Experimental and reuse results suggest that the synthesized material is an excellent photocatalyst with advantages such as both performance and reusability.
