WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collections

Permanent URI for this collectionhttps://hdl.handle.net/20.500.13091/2

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Now showing 1 - 20 of 180

Citation - WoS: 18
Citation - Scopus: 24
Adsorption of Cr(vi) Onto Cross-Linked Chitosan-Almond Shell Biochars: Equilibrium, Kinetic, and Thermodynamic Studies
(SPRINGER INTERNATIONAL PUBLISHING AG, 2021) Altun, Türkan; Ecevit, Hüseyin; Kar, Yakup; Çiftçi, Birsen
In this study, to remove Cr(VI) from the solution environment by adsorption, the almond shell was pyrolyzed at 400 and 500 degrees C and turned into biochar (ASC400 and ASC500) and composite adsorbents were obtained by coating these biochars with chitosan (Ch-ASC400 and Ch-ASC500). The resulting biochars and composite adsorbents were characterized using Fourier transform infrared (FTIR) spectroscopy; Brunauer, Emmett, and Teller (BET) surface area; scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX); and the point of zero charge pH (pH(pzc)) analyses. The parameters affecting the adsorption were examined with batch adsorption experiments and the optimum parameters for the efficient adsorption of Cr(VI) in 55 mg L-1 solution were determined as follows; adsorbent dosages: 5 g L-1 for biochars, 1.5 g L-1 for composite adsorbents, contact time: 120 min, pH: 1.5. It was seen that the temperature did not affect the adsorption much. Under optimum conditions, Cr(VI) adsorption capacities of ASC400, ASC500, Ch-ASC400, and Ch-ASC500 adsorbents are 11.33, 11.58, 37.48, and 36.65 mg g(-1), respectively, and their adsorption percentages are 95.2%, 97.5%, 94.3%, and 94.0%, respectively. Adsorption data were applied to Langmuir, Freundlich, Scatchard, Dubinin-Radushkevic, and Temkin isotherms and pseudo-first-order kinetic model, pseudo-second-order kinetic model, intra-particle diffusion model, and film diffusion model. The adsorption data fitted well to the Langmuir isotherm and pseudo-second-order kinetic models. From these results, it was determined that chemical adsorption is the dominant mechanism. Also, both intra-particle diffusion and film diffusion is effective in the adsorption rate. For all adsorbents, the Langmuir isotherm proved to be the most appropriate model for adsorption. The maximum monolayer adsorption capacities calculated from this model are 24.15 mg g(-1), 27.38 mg g(-1), 54.95 mg g(-1), and 87.86 mg g(-1) for ASC400, ASC500, Ch-ASC400, and Ch-ASC500, respectively. The enthalpy change, entropy change, and free energy changes during the adsorption process were calculated and the adsorption was also examined thermodynamically. As a result, adsorption occurs spontaneously for all adsorbents.
Citation - WoS: 42
Citation - Scopus: 49
Adsorption of Malachite Green and Methyl Violet 2b by Halloysite Nanotube: Batch Adsorption Experiments and Box-Behnken Experimental Design
(Elsevier Ltd, 2022) Altun, Türkan; Ecevit, Hüseyin
Dyes constitute a significant part of the pollutants in industrial wastewater. In this study, halloysite nanotube (HNT) was used for adsorption of malachite green and methyl violet 2B dyes from the solution. Using batch adsorption experiments and response surface method, parameters affecting adsorption have been optimized. As a consequence of the batch experiments, after 60 min, the adsorption equilibrium state was achieved at 3 g L?1 HNT dosage, 125 mg L?1 dye concentration and natural solution pH. Temperature did not significantly affect the adsorption. The adsorption equilibrium data can be said to have fitted the Langmuir, Freundlich, Dubinin-Radushkevich and Temkin isotherms well for the both dyes. The Langmuir maximum monolayer malachite green and methyl violet 2B adsorption capacities (As) of HNT are 74.95 mg g?1 and 67.87 mg g?1, respectively. Adsorption processes are more consistent with the pseudo-second-order kinetic model. In addition, both intra-particle diffusion and film diffusion are effective as rate-determining steps in adsorption. Thermodynamic calculations showed that the adsorption is exothermic and spontaneous. The regeneration of HNT after adsorption was confirmed in five cycles. By using the Box-Behnken response surface method, the parameters affecting the adsorption process were modeled, the effects of these parameters on the adsorption efficiency were expressed mathematically and the optimum operating parameters were determined. © 2022
Citation - WoS: 25
Citation - Scopus: 29
Aerogels as Promising Materials for Antibacterial Applications: a Mini-Review
(ROYAL SOC CHEMISTRY, 2021) Kaya Güzel, Gülcihan; Aznar, Elena; Deveci, Hüseyin; Martinez-Manez, Ramon
The increasing cases of bacterial infections originating from resistant bacteria are a serious problem globally and many approaches have been developed for different purposes to treat bacterial infections. Aerogels are a novel class of smart porous materials composed of three-dimensional networks. Recently, aerogels with the advantages of ultra-low density, high porosity, tunable particle and pore sizes, and biocompatibility have been regarded as promising carriers for the design of delivery systems. Recently, aerogels have also been provided with antibacterial activity through loading of antibacterial agents, incorporation of metal/metal oxides and via surface functionalization and coating with various functional groups. In this mini-review, the synthesis of aerogels from both conventional and low-cost precursors is reported and examples of aerogels displaying antibacterial properties are summarized. As a result, it is clear that the encouraging antibacterial performance of aerogels promotes their use in many antibacterial applications, especially in the food industry, pharmaceutics and medicine.
Citation - WoS: 14
Citation - Scopus: 13
All-Dry Hydrophobic Functionalization of Paper Surfaces for Efficient Transfer of Cvd Graphene
(WILEY-V C H VERLAG GMBH, 2019) Çıtak, Emre; İstanbullu, Bilal; Şakalak, Hüseyin; Gürsoy, Mehmet; Karaman, Mustafa
In this study, the successful transfer of chemical vapor deposition (CVD)-grown graphene on an ordinary printing paper surface is demonstrated. Pristine paper is not a suitable substrate for graphene transfer because of its fragile and hydrophilic nature against the chemicals used during the transfer process. Two different fluoroalkyl polymers, namely poly(hexafluorobutyl acrylate) (PHFBA) and poly(perfluorodecyl acrylate) (PPFDA) are coated on paper surfaces by an initiated CVD (iCVD) technique to make the paper surfaces hydrophobic. Hydrophobicity is found to be an important factor in order for the graphene to be transferred onto the paper substrate. Although surfaces coated with PPFDA possess better hydrophobicity owing to their longer perfluoroalkyl group and higher roughness, the graphene transfer is found to be more successful on a PHFBA-coated surface. A thin film of PHFBA on the paper surface acts as a prime layer for effective and defect-free transfer of graphene and makes the paper surface ideal and robust during the graphene transfer process. The as-transferred graphene layer on the PHFBA-coated paper surface shows high conductivity values, even after repeated folding and flattening cycles.
Citation - WoS: 23
Citation - Scopus: 24
All-Dry Patterning Method To Fabricate Hydrophilic/Hydrophobic Surface for Fog Harvesting
(SPRINGER, 2020) Gürsoy, Mehmet
Inspired by natural creatures that live in the arid climate, fog harvesting can be an efficient approach to overcome freshwater scarcity. Fog harvesting ability of the creatures is mainly based on wettability differences of their surfaces. In this study, inspired by creatures that have hydrophilic regions surrounded by hydrophobic areas, a novel all-dry patterning method was applied to fabricate hydrophilic/hydrophobic patterned surfaces for fog harvesting. For this purpose, patterned surfaces were produced using plasma-enhanced chemical vapor deposition (PECVD) method with the help of a commercial magnet and iron powders. The idea behind the use of the magnetic field during PECVD deposition is to hold light iron particles on the substrate under the vacuum environment for masking substrate surface. For the first time, the magnetic field was used to fabricate patterned surfaces in vapor-phase polymerization. Ordinary glass slides were successfully transformed into hydrophilic/hydrophobic patterned glasses. The obtained results showed that the combination of hydrophobic and hydrophilic regions improved the fog harvesting performance.
Citation - WoS: 14
Citation - Scopus: 14
All-Dry Synthesis of Poly(2-Ethylhexyl Acrylate) Nanocoatings Using Initiated Chemical Vapor Deposition Method
(ELSEVIER SCIENCE SA, 2019) Şakalak, Hüseyin; Karaman, Mustafa
In this study, Poly(2-ethylhexyl acrylate) (PEHA) thin films were deposited on different substrates by initiated chemical vapor deposition (iCVD) technique. Being a long alkyl chain acrylate with a suitably low glass transition temperature, PEHA is an important member of acrylates family, which is used extensively in adhesives, paints, and coating applications. In iCVD, use of the tert-butyl peroxide as an initiator allowed a deposition rate of 155 nm/min at a filament temperature of 280 degrees C. Precursor flow ratios, filament and substrate temperatures were found to be important parameters that effect the deposition rates. The negative relation between substrate temperature and deposition rates implied an adsorption limited kinetics. FTIR and XPS analyses of the deposited films confirmed that the chemical functionality of the EHA monomer preserved well after iCVD. It was also revealed that the as-deposited films are smooth, uniform and optically transparent. PEHA film deposited by iCVD on glass improved the optical transmittance of glass, by acting as an anti-reflection coating due to its suitable refractive index of 1.45.
Citation - WoS: 17
Citation - Scopus: 19
Analysis of Electrospinning and Additive Effect on ? Phase Content of Electrospun Pvdf Nanofiber Mats for Piezoelectric Energy Harvester Nanogenerators
(Institute of Physics, 2022) Oflaz, Kamil; Özaytekin, İlkay
Harvesting energy with piezoelectric nanoparticles enables the development of self-powered devices. Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF) has been widely used in a variety of fields due to its superior piezoelectric properties. PVDF’s piezoelectric performance is affected by the presence of polar phase in the crystalline structure. The electrospinning process was used in this study to achieve high ? phase ratios in the PVDF crystalline structure using various additives (graphene, boron nitride, and quartz (SiO2)). The Taguchi experimental design method was used to determine the most significant parameters affecting ? phase content from seven factors, as well as the optimal levels of the significant factors. The Fourier transform infrared, x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray and differential scanning calorimetry analyses were used to characterize the composite PVDF nanofiber mats produced under optimal conditions, and the output voltage was measured using an oscilloscope. The composite PVDF nanofiber mat with the highest ? phase concentration demonstrated a maximum output voltage of 8.68 V under optimal conditions, indicating that it outperformed than pure PVDF under equal electrospinning conditions. © 2022 IOP Publishing Ltd.
Citation - WoS: 18
Citation - Scopus: 19
Antibacterial Activity of Linezolid Against Gram-Negative Bacteria: Utilization of Epsilon-Poly Capped Silica Xerogel as an Activating Carrier
(MDPI, 2020) Kaya Güzel, Gülcihan; Medaglia, Serena; Candela-Noguera, Vicente; Tormo-Mas, Maria Angeles; Marcos, Maria Dolores; Aznar, Elena; Martinez-Manez, Ramon
In recent times, many approaches have been developed against drug resistant Gram-negative bacteria. However, low-cost high effective materials which could broaden the spectrum of antibiotics are still needed. In this study, enhancement of linezolid spectrum, normally active against Gram-positive bacteria, was aimed for Gram-negative bacteria growth inhibition. For this purpose, a silica xerogel prepared from a low-cost precursor is used as a drug carrier owing to the advantages of its mesoporous structure, suitable pore and particle size and ultralow density. The silica xerogel is loaded with linezolid and capped with epsilon-poly-l-lysine. The developed nano-formulation shows a marked antibacterial activity against to Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. In comparison to free linezolid and epsilon-poly-l-lysine, the material demonstrates a synergistic effect on killing for the three tested bacteria. The results show that silica xerogels can be used as a potential drug carrier and activity enhancer. This strategy could provide the improvement of antibacterial activity spectrum of antibacterial agents like linezolid and could represent a powerful alternative to overcome antibiotic resistance in a near future.
Citation - WoS: 8
Citation - Scopus: 8
Application of the Central Composite Design and Response Surface Methodology for Investigation of Induction Time, Conjugated Diene, Conjugated Triene and Trans Fatty Acid Content of Corn Oil Enriched With Carotenoids
(SPRINGER, 2020) Topkafa, Mustafa
The central composite design technique was used to investigation of induction time, conjugated diene, conjugated triene and trans fatty acid content of corn oil enriched with lutein, beta-carotene and lycopene in this study. The levels of lutein and beta-carotene and were between 0 and 94 mg/kg, while lycopene levels was 0-49.56 mg/kg. Oil samples with and without lutein, beta-carotene and lycopene were prepared according to central composite design. The influence of these three independent variables on the four dependent variables such as time, conjugated diene and conjugated triene and trans fatty acid content was evaluated using a reduced cubic model. The each independent variable was effective on the induction time, conjugated diene, conjugated triene and trans fatty acid content of corn oil. The positive effect on the induction time was observed high concentrations of lutein and lycopene concentrations. Lutein, beta-carotene and lycopene had a significant effect on conjugated diene, conjugated triene and trans fatty acid content. The desirability function and the 3D plots suggested that optimum parameters were lutein concentration of 19 mg/kg, beta-carotene concentration of 19 mg/kg and lycopene concentration of 12.5 mg/kg as optimum parameters for maximum induction time and the minimum formation of conjugated diene, conjugated triene and trans fatty acid species.
Citation - WoS: 25
Citation - Scopus: 25
Application of Various Carboxylic Acids Modified Walnut Shell Waste as Natural Filler for Epoxy-Based Composites
(WILEY, 2021) Albaker, Ruya Isam Bakr; Kocaman, Süheyla; Martı, Mustafa Esen; Ahmetli, Gülnare
In this study, chemically modified walnut shells (WS) were used as the filling material for synthesis of bio-based epoxy composites and added to the matrix at varied mass ratios (10%-50%). The shells were initially treated with alkali and then modified with three different organic acids (citric acid [CA], oxalic acid [OA], and formic acid [FA]). The WS were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDX) and thermo gravimetric analyzer. The SEM and X-ray diffraction were employed to observe the morphology of the composites. The influences of acid type and WS percentages on the mechanical, thermal and water sorption properties were investigated. The maximum tensile strength (124.8 MPa) was obtained with CA-treated shells (CA-WS) and followed by OA-treated shells (OA-WS) (117 MPa) and FA-treated shells (FA-WS) (96.5 MPa). Acid modification had a positive effect on Young's modulus as that of epoxy resins increased by 5.45%-50.91%. The treatment did not significantly affect hardness. The optimum amount of modified shells in the composites was found to be 20 wt%. Water sorption values changed in the range of 2.78%-3.42% for composites with 20 wt% WS and observed to increase with the filler amount in the composite. However, this trend and the slight decrease in thermal properties are not critical obstacles for the use of modified WS in the manufacture of inexpensive epoxy- and bio-based eco-friendly products.
Citation - WoS: 5
Citation - Scopus: 6
Appraisal of Inorganic and Lignocellulosic Organic Shell Wastes as a Green Filler in Epoxy-Based Hybrid Composites
(Elsevier, 2025) Ahmetli, Gulnare; Kocaman, Suheyla; Soydal, Ulku; Kocak, Beril; Ozmeral, Nimet; Musayev, Nijat
Hybrid composites are now becoming increasingly important regarding economic and ecological compatibility. This study presented the research results that evaluate the feasibility of using cherry pit shell (CPSh) and chicken eggshell (ChESh) natural wastes as a new hybrid filler mixture for the first time. CPSh and ChESh can reduce the composite material cost and increase the biobased content. CPSh was treated with a 5 % NaOH alkali solution to enhance the lignocellulosic filler-matrix interfacial interaction. Hybrid green organic and inorganic fillers were used in the epoxy matrix (ER). Morphological, water absorption, thermal, and mechanical performance of hybrid composites were investigated. The tensile strength of ER increased max. by 5.73, 7.3, 17.98, and 14.27 % in the case of raw CPSh, ChESh, and hybrid filler mixtures at 1:1 and 1:3 wt mixing ratios of alkali-treated CPSh (NaOHCPSh) and ChESh, respectively. The composites' thermal stability and dynamic-mechanical properties in different aging environments (seawater and hydrothermal) were examined by thermogravimetric analysis (TGA) and dynamic-mechanical analysis (DMA). Hydrothermal was the most affected aging condition on the composite properties. In addition, ANOVA is applied to find the significant effect of different weight percentages of hybrid fillers on the mechanical properties of composites.
Citation - WoS: 42
Citation - Scopus: 46
Apricot Kernel Shell Waste Treated With Phosphoric Acid Used as a Green, Metal-Free Catalyst for Hydrogen Generation From Hydrolysis of Sodium Borohydride
(PERGAMON-ELSEVIER SCIENCE LTD, 2020) Fangaj, Enis; Ceyhan, Ayhan Abdullah
In this study, grinded apricot kernel shell (GAKS) biobased waste was used for the first time as a cost-effective, efficient, green and metal-free catalyst for hydrogen generation from the hydrolysis reaction of sodium borohydride (NaBH4). For the hydrogen production by NaBH4 hydrolysis reaction, GAKS was treated with various acids (HCl, HNO3, CH3COOH, H3PO4), salt (ZnCl2) and base (KOH). As a result, the phosphoric acid (H3PO4) demonstrated better catalytic activity than other chemical agents. The hydrolysis of NaBH4 with the GAKS-catalyst (GAKS(cat)) was studied depending on different parameters such as acid concentration, furnace burning temperature and time, catalyst amount, NaBH4 concentration and hydrolysis reaction temperature. The obtained GAKS(cat) was characterized by ICP-MS, elemental analysis, TGA, XRD, FT-IR, Boehm, TEM and SEM analyses and was evaluated for its catalytic activity in the hydrogen production from the hydrolysis reaction of NaBH4. According to the results, the optimal H3PO4 percentage was found as 15%. The maximum hydrogen generation rate from the hydrolysis of NaBH4 with the GAKS(cat) was calculated as 20,199 mL min(-1) g(cat)(-1) As a result, it can be said that GAKS treated with 15% H3PO4 as a catalyst for hydrogen production is an effective alternative due to its high hydrogen production rate. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Behaviors of Removing Diesel Oil From Water With Ps/Ti4o7 Composite Nanofibers: Modeling Diesel Oil Sorption Capacity for Tap Water and Investigation of the Effects of Ph on Sorption at Different Temperatures for Times
(Springer Heidelberg, 2022) Dinçer, Kevser; Özaytekin, İlkay
In this study, pure polystyrene nanofiber and polystyrene composite nanofibers with different ratios of Ti4O7 were obtained. Diesel oil sorption of the obtained nanofibers was investigated in two experimental studies. The aim of the first was to experimentally determine the nanofiber with the fastest diesel oil sorption capacity. For this purpose, the diesel oil sorption capacity (q) was examined for both pure polystyrene (PS) nanofibers and PS nanofibers with 15 wt% and 25 wt% Ti4O7 nanoparticle additives in different volumetric mixing ratios (Vr) of diesel oil and tap water. The results of this study determined that the fastest diesel oil sorbent capacity was formed in 15 wt% Ti4O7 nanoparticle-doped PS nanofiber (PSNF2). The data were modeled with Rule-Based Mamdani Type Fuzzy Logic (RBMTF). The input parameters of RBMTF were density (D), Vr, time (t), initial mass of fibers (m(o)), and tap water sorption mass (m(w)), while the q was output parameter. The multiple coefficient of determination for q was calculated as R-2 = 0.9825. The purpose of the second experimental study was to examine the behavioral performance (Delta m) of nanoparticles-doped PS nanofibers (PSNF2), which has the fastest the diesel oil sorption capacity, at different pH and different temperatures, according to different timings. In this experimental study, it was determined that the behavior performance of PSNF2 was the highest at pH7, especially at 20 degrees C for the first minute.
Citation - WoS: 37
Citation - Scopus: 47
Behaviour of Waste Polypropylene Pyrolysis Char-Based Epoxy Composite Materials
(SPRINGER HEIDELBERG, 2020) Soğancıoğlu, Merve; Yel, Esra; Ahmetli, Gülnare
In this study, polypropylene (PP) plastic wastes were pyrolysed. Solid pyrolysis product (char) was used as filler material for the preparation of epoxy composite. 300, 400, 500, 600 and 700 degrees C were selected as final pyrolysis temperatures. Solid pyrolysis product (char) was analysed by elemental, FTIR, SEM, BET and TGA analysis. The epoxy composite samples were prepared with char obtained from pyrolysis. Mechanical properties of composites were analysed by hardness, tensile strength, elongation at break, electrical conductivity tests to explain the effects of pyrolysis temperature and char doses over composite properties. Thermogravimetric properties of composites were determined by TGA analyses. The water absorption behaviour of composite samples was determined by water adsorption test. Epoxy composite produced from PP char obtained under 300 degrees C showed the most ideal behaviour.
Citation - WoS: 5
Citation - Scopus: 7
Biochar Produced From Co-Pyrolysis of Olive Pomace & Crude Oil as an Adsorbent for Cr (vi) Removal From Aqueous Solutions
(Iranian Institute of Research and Development in Chemical Industries, 2022) Almezgagi, Maha; Kaya Güzel, Gülcihan; Kar, Yakup; Deveci, Hüseyin
This study investigated aqueous solution treatment to remove Cr (VI) using a biochar-based adsorbent. Olive pomace and crude oil were used to synthesize the biochar adsorbent via co-pyrolysis for the first time. The biochar properties were examined with Fourier Transform Infra-Red (FT-IR) spectroscopy, scanning electron microscopy (SEM), and Energy Dispersive X-ray (EDX) analyses before and after adsorption. The adsorption experiments were carried out in a batch process under different experimental conditions. The optimum adsorption efficiency was experimentally found to be at pH of 1.5, contact time of 15 min, Cr (VI) initial concentration of 20 mg/L, adsorbent dose of 0.4 g, and 303 K. Langmuir and Freundlich isotherms were used to evaluating the adsorption performance of biochar, and the Langmuir isotherm model was well fitted to experimental data with a maximum adsorption capacity of 9 mg/g. Kinetic experimental data was best described using a pseudo-second-order kinetic model. The thermodynamic parameters of the adsorption process were examined in detail, and the process was exothermic and spontaneous in nature. It is concluded that biochar can be successfully used as an adsorbent for the treatment of Cr (VI) contaminated water. Additionally, the evaluation of olive pomace provided not only a decrease in waste accumulation in the olive production industry but also the synthesis of an inexpensive and environmentally friendly adsorbent. © 2022, Iranian Institute of Research and Development in Chemical Industries. All rights reserved.
Citation - WoS: 15
Citation - Scopus: 16
Biogenic Amine Contents in Turkish Dairy Products: Determination and Comparison
(SPRINGER, 2021) Pekcici, Mustafa Ender; Güler, Ebru; Topkafa, Mustafa
Biogenic amines in dairy products such as pasteurized milk, gluten-free and lactose-free milk, lactose-free milk, milk cream, yoghurt, kefir, cottage cheese, kasar cheese, tulum cheese and kuflu cheese were evaluated by using liquid chromatography (HPLC) technique and compared in detail with literature. The HPLC method used for the separation of biogenic amines has been validated in terms of suitability, linearity, accuracy and sensitivity. For the used reversed-phase high-performance liquid chromatography method, the linearity were investigated in the concentration ranges of 0.01-10 mg/L (R-2 = 0.996-0.999) for all biogenic amines. Mean recoveries for all biogenic amines ranged from 95 to 100.7%. The limits of detection and quantification were 6.13 x 10(-4)-3.22 x 10(-3) mg/L and 2.04 x 10(-3)-1.07 x 10(-2) mg/L, respectively. Tyramine, putrescine and spermine were detected in all products while other types were not determined in some products. The total amount of biogenic amines in pasteurized milk (12.48-19.82 mg/kg) were higher than both gluten-free and lactose-free milk (11.64 mg/kg) and lactose-free milk (8.65-10.33 mg/kg). It has been observed that the amount of tyramine and sermine in kefir and yoghurt products were similar. While cottage, kasar and tulum cheese products contained higher amount of tyramine compared to other biogenic amines, kuflu cheese was possessed of cadaverine. Although the types and amounts of biogenic amines in dairy products in Turkey were examined in many previous studies, it was evaluated in detail and combined in this study. In addition, gluten-free and lactose-free milk, lactose-free milk, milk cream and kuflu cheese were evaluated for the first time.
Citation - WoS: 15
Citation - Scopus: 14
Biomimetic Surfaces Prepared by Soft Lithography and Vapour Deposition for Hydrophobic and Antibacterial Performance
(TAYLOR & FRANCIS LTD, 2022) Gürsoy, Mehmet; Testici, Hilal; Çıtak, Emre; Kaya, Murat; Dağı, Hatice Türk; Öztürk, Bahadır; Karaman, Mustafa
This study demonstrates the synthesis of a bioinspired surface exhibiting hydrophobic and antibacterial functionalities using a two-stage synthesis approach which involves soft lithography and initiated chemical vapour deposition (iCVD). Sandpapers, which are inexpensive and available with desired grit size, were used as the moulds in soft lithography to transfer the rough surface patterns to the PDMS replica surfaces. The antibacterial surface modification of the PDMS replicas was done through vapour-phase deposition of thin poly(diethylaminoethyl methacrylate-vinylbenzyl chloride) (P(DEAEMA-VBC)) films by iCVD method from the corresponding monomers. FTIR analysis of the as-deposited films showed a high retention of the chemical functionalities. The hydrophobicity and antibacterial performances of the flat and rough surfaces were examined as a function of surface roughness. The antibacterial activities were tested against gram-negative E. coli and gram-positive S. aureus. It was found that obtained replicas achieved up to a 7-log reduction in bacterial population and showed high hydrophobicity.
Citation - WoS: 44
Citation - Scopus: 47
Biosorption of Methylene Blue and Malachite Green on Biodegradable Magnetic Cortaderia Selloana Flower Spikes: Modeling and Equilibrium Study
(TAYLOR & FRANCIS INC, 2021) Parlayıcı, Şerife; Pehlivan, Erol
This study involves the production of a novel biosorbent obtained fromCortaderia selloanaflower spikes (CSFs). MagneticC. selloanaflower spikes (nM infinity CSFs) was applied as an ideal biosorbent for the elimination of dyes from water. They were utilized for the removal from aqueous solutions of malachite green (MG) and methylene blue (MB) dyes. The analyses of the equilibrium were done under certain experimental parameters such as contact time, initial dye concentration, pH, and quantity of biosorbent. The rapid intake of dyes to reach the equilibrium in a short period time showed the effectiveness of nM infinity CSFs to adsorb MG and MB. The experimental information of MB and MG was obtained from the Langmuir model and it confirmed the magnificent dye biosorption ability; 72.99 mg/g for CSFs/MB, 119.05 mg/g for nM infinity CSFs/MB, 31.06 mg/g for CSFs/MG, and 56.50 mg/g for nM infinity CSFs/MG. Langmuir's model affirmed the excellent dye biosorption ability. The pseudo-second-order kinetic model displayed a great fit to the experimental result for the removal of MG and MB. The nM infinity CSFs compared with raw biosorbent affirmed that the magnetic form of the biosorbent has a greater removal ability for MB and MG. nM infinity CSFs is a noteworthy biosorbent for MB and MG removal from wastewater. [GRAPHICS] HIGHLIGHTS Magnetic Cortaderia selloana flower spikes (nM1CSFs) was synthesized for the biosorption of dyes FT-IR and SEM analysis were used for characterization. The Langmuir isotherm model fitted the data of the adsorption for nM1CSFs nM1CSFs is a noteworthy biosorbent for MB and MG removal from wastewater.
Citation - WoS: 36
Citation - Scopus: 39
Boron Removal and Antifouling Properties of Thin-Film Nanocomposite Membrane Incorporating Pecvd-Modified Titanate Nanotubes
(WILEY, 2019) Ng, Zhi-Chien; Chong, Chun-Yew; Lau, Woei-Jye; Karaman, Mustafa; Ismail, Ahmad Fauzi
BACKGROUND Incorporation of nanofillers into the polyamide (PA) layer of thin-film composite (TFC) membrane could improve membrane surface properties for enhanced water separation efficiency. However, most nanofillers do not disperse well in organic medium. In this work, the surface of titanate nanotubes (TNTs) was modified via the plasma-enhanced chemical vapour deposition (PECVD) method in order to promote its dispersion rate (in organic medium) during thin-film nanocomposite (TFN) membrane fabrication. RESULTS Fourier transform infrared (FTIR) analysis confirmed the surface chemistry of TNTs coated by hexafluorobutyl acrylate (HFBA) or hydroxyethyl methacrylate (HEMA) via PECVD method. The effects of embedding modified TNTs into the PA layer on membrane surface morphology, hydrophilicity and performance were also investigated and the results were further compared with commercial reverse osmosis (RO) membranes. It was found that the incorporation of HFBA- and HEMA-modified TNTs could enhance the membrane water permeability by >25% and >40%, respectively, without compromising their salt rejection. The boron rejections of TFN membranes incorporated with HFBA- and HEMA-modified TNTs meanwhile were recorded at 75.56% and 70.73%, respectively; these values were relatively higher than those for the self-synthesized TFC (68.57%) and commercial RO membranes (37-39%). The developed TFN membranes also exhibited higher fouling tolerance than the commercial RO membranes, achieving >94% of water flux regeneration as a result of enhanced membrane surface hydrophilicity. CONCLUSION Compared to hydrophilic modification using HEMA, nanofillers modified by hydrophobic HFBA proved more effective at producing a PA layer with better nanofiller distribution, making the resultant TFN membrane more suitable for desalination processes. (c) 2019 Society of Chemical Industry
Citation - WoS: 13
Citation - Scopus: 14
Calixarene-Tethered Textile Fabric for the Efficient Removal of Hexavalent Chromium From Polluted Water
(ELSEVIER, 2021) Özçelik, Egemen; Mercan Sevgili, Emine; Erdemir, Serkan; Karaman, Mustafa; Tabakcı, Mustafa
This study describes the tethering of dimethylamionomethyl bonded calixarene (DMAM-calixarene) onto cotton fabric surface functionalized with poly(glycidyl methacrylate) (PGMA) linker layer using initiated chemical vapor deposition (iCVD) technique and the efficient adsorption capability of DMAM-calixarene functional textiles for the toxic hexavalent chromium from polluted water. The characterization of DMAM-calixarene-tethered textile fabric was performed by FTIR and XPS spectroscopy. Cr(VI) solutions was passed over packed DMAMcalixarene-tethered textile fabric adsorbent and the highest adsorption was observed at pH 2 in dichromate anion form of COS. The regeneration and selectivity studies indicate that the DMAM-calixarene-tethered textile fabric has outstanding adsorbent features in used experimental conditions for hexavalent chromium. Moreover, it was observed that both H-bonding and electrostatic interactions were significant factors in the dichromate anion adsorption process. Thus, this study clearly revealed that any DMAM-calixarene-tethered textile fabric can be easily used as a selective hexavalent chromium capture filter in geographic regions lacking appropriate wastewater purification systems.

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