Sürdürülebilir Kalkınma Amaçları

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• MakaleYalnız künye2024Scopus SJRQ1/r/munzur/2165
  Synthesis, characterization and application of cross-linked functional terpolymer through epoxy group as sorbent for extraction of cadmium from waters and foods: Multivariate optimization

  Yılmaz, Ersen; Boztuğ, Ali; Ul Haq, Hameed; Boczkaj, Grzegorz; Altunay, Nail

  The purpose of this study was to develop a selective sorbent for cadmium ions (Cd(II)) enrichment in orbital shaker assisted solid phase microextraction (OS-SPME) from different aqueous and food samples. A maleic anhydride-styrene-glycidyl methacrylate (MA-St-GMA) terpolymer was synthesized and characterized in detail. Experimental variables of sample preparation step were optimized using a central composite design (CCD). The final determination step was performed using flame atomic absorption spectroscopy (FAAS). The MA-St-GMA sorbent exhibited a high adsorption capacity (195.9 mg g−1) for the Cd(II) ion. The developed method under optimal conditions provides satisfactory performance and a significant improvement compared to other protocols available in the literature. The linear range and detection limit of the method is 0.1–130 ng mL−1 and 0.03 ng mL−1, respectively. The robustness, intraday/interday precision, selectivity, and accuracy of the method were investigated. To further validate the method, a dedicated series of analysis was performed using certified reference materials (CRMs). This part of the study confirmed the applicability of the method for routine analysis. The OS-SPME-FAAS method was validated using water and food samples. Relative standard deviations and recovery for real-world samples were in ranges 1.7–2.2 % and 95.5–98.5 %, respectively. As a result, the MA-St-GMA sorbent showed that it could quantitatively extract Cd(II) ions from aqueous solution.

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  AtıfScopus9·WoS8·OpenAlex9

  İncele
• MakaleAçık Erişim2022/r/munzur/6566
  Karışmaz PMMA/PS harmanlarının optik özelliklerine uyumlulaştırıcı etkisi

  Yilmaz, Ersen

  Karışmayan polimetil metakrilat/polistiren (PMMA/PS) harmanları değişik maleik anhidrit-stiren-metil metakrilat (MAStMMA) uyumlaştırıcı oranı (0, 2, 4, 6, 8 ve 10) eklenerek çözeltiden döküm yoluyla elde edilmiştir. Spektral sonuçlar, kırılma indisi (n), sönüm katsayısı (k) ve absorpsiyon katsayısı (µ) gibi optik sabitlerin terpolimer bazlı uyumlaştırıcı ilavesiyle arttığını göstermiştir. Diğer yandan optik enerji boşluğu Eg, anılan optik sabitlere göre zıt bir eğilim göstermiştir. Gözlenen en düşük enerji boşluğu %8 ila %10 uyumlaştırıcı oranı arasında belirlenmiştir.

  AtıfOpenAlex2

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• MakaleYalnız künye2022/r/munzur/6556
  Blending Effect of Maleic Anhydride-Styrene-Methyl Methacrylate Terpolymer on Polyvinylchloride (Pvc)/Polystyrene (Ps) Mixtures

  Yilmaz, Ersen

  The blending effect of poly maleic anhydride-styrene-methyl methacrylate (MA-St-MMA) terpolymer on nonmiscible PVC and Polystyrene was studied depending on their thermomechanical properties. Depending on the amount of the synthesized and used compatibilizer the tensile strength, modulus, and thermomechanical properties of the blends are enhanced. The unmodified and blends with small amounts of compatibilizer exhibit two-step degradation whereas those containing 6, 8 and 10 percent compatibilizer showed a single glass transition (Tg). All the results reveal that PS/PVC mixtures modified with MA-St-MMA have superior mechanical properties and phase adhesions than mixtures without terpolymer.

  İncele
• MakaleAçık Erişim2022/r/munzur/6544
  Viscometric Investigation of Compatibilizer Effect on Polyvinyl chloride/Polystyrene Blends

  Yilmaz, Ersen; Boztuğ, Ali

  In this study, polyvinyl chloride (PVC) and polystyrene (PS) polymers, which do not form a compatible blend with each other in certain concentration ranges and are widely used on an industrial scale, were used. The concentration range in which these two polymers do not form a compatible blend were determined viscometrically, and maleic anhydride-styrene (MAS) copolymer was added as a compatibilizing agent in this concentration range. The concentration range in which the polymer pair did not form a compatible blend was determined as 1.5 and 2.0 g dL-1. In this concentration range, 5.0 and 10.0 % MAS copolymer was added to the polymer couple and its compatibilizing effect was investigated. It was determined by viscometric method that the MAS copolymer was a good compatibilizer in the range where the polymer pair did not form a compatible blend.

  AtıfOpenAlex1

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• MakaleAçık Erişim2022/r/munzur/6537
  Green Synthesis of Gold Nanoparticles Using Aqueous Extract of Asphodelus Aestivus, Coating with Chitosan Biopolymer and Cytotoxicity Studies

  Ates, Mehmet; Yilmaz, Ersen; Erbay, Muhammed

  The green synthesis of gold nanoparticles (Au-NPs) was carried out by pouring the aqueous extract of East Anatolian origin Asphodelus aestivus plant onto aqueous gold metal ions and reducing them via single-step one- pot method. The absorption peak of the synthesized nanoparticles gave a maximum at 575 nm. All the X-ray diffraction peaks at 2θ = 38.25 , 44.46 , 64.64 and 77.20 that index to (111), (200), (220), and (311) planes verify the successful synthesis of Au-NPs. Mostly spherical shape particles showed a homogeneous distribution with size range 20±5 nm are measured using TEM. From the FTIR spectrum, the peaks are seems to be related to phenolic compounds, flavonoids, benzophenones, terpenoids and anthocyanins which assume that they could act as the reducing agents. The plant extraction, one-pot, single-step method used is environmentally safe without the role of synthetic materials which is highly potential in mild and green synthesis applications. The Au-NPs were coated with chitosan biopolymer in aquatic solution medium and verified by SEM. Then, cytotoxic investigations of the biosynthesized Au-NPs were carried out by HUVEC cells. Au-NPs were showed toxic effects on cell culture, even if in a small amount. However, chitosan biopolymer coating increased cell viability.

  AtıfOpenAlex3

  İncele
• MakaleYalnız künye2022Scopus SJRQ2/r/munzur/2693
  Compatibilization of polyvinyl chloride - polymethyl methacrylate polymer blends with maleic anhydride-styrene-methyl methacrylate terpolymer

  Yilmaz, Ersen

  In this study, nonmiscible polyvinyl chloride (PVC) and polymethyl methacrylate (PMMA) polymers were made miscible by using MA-St-MMA terpolymer as a compatibilizer. Maleic anhydride-styrene-methyl methacrylate (MA-St-MMA) terpolymer was synthesized in our laboratory and used. The synthesized terpolymer was determined by FT-IR spectroscopy. Equal mass PVC/PMMA mixture samples were prepared in series and the compatibilizer terpolymer varying between 2% and 10% by mass was added to the samples and the effect of the added terpolymer on the miscibility was determined viscometrically, thermally, mechanically and, visually. With the addition of the compatibilizer, the two components in the mixture behave like a single polymer with a single glass transition temperature (Tg) and the mixture became compatible. As a result of viscometric experiments, it has been determined that with the added MA-St-MMA terpolymer, the Δb value derivated from the Krigbaum-Wall equation which is the miscibility parameter of a mixture shifted into the positive (+) zone indicating that the two polymers became miscible. By visual analysis, it was observed that the added terpolymer reduced the opaque appearance and the phase separations of the mixture. From the tensile test, a significant improvement in impact toughness was observed. When all the data obtained were evaluated, it was determined that the synthesized MA-St-MMA terpolymer was a suitable compatibilizer for the mixture of PVC and PMMA.

  AtıfScopus5·WoS5·OpenAlex8

  İncele
• MakaleAçık Erişim2021/r/munzur/3956
  Synthesis and Characterization of Silver Nanoparticles and Coating with Chitosan

  Ates, Mehmet; Yilmaz, Ersen; Kar, Bulent; Durukan, Ilknur Kars

  Recent advancements in nanotechnology have garnered increasing attention due to the improvements in producing and utilizing particles whose sizes are extremely small. There is particular interest in metal nanoparticles due to their distinctive properties. Silver nanoparticles (Ag-NPs) have been of particular interest owing to their unique electrical, optical and physicochemical properties as well as their biomedical applications. Ag-NPs are the fastest growing class of nanoscale materials because of their antibacterial activities. They are now considered to be the next generation antimicrobials. Today, owing to their disinfectant properties, Ag-NPs are extensively used in numerous consumer products, including disinfecting medical devices and home appliances, paints, optical devices, plastics, textiles, soaps and laundry detergents, cosmetics, health-care products, as well as in food packing and food products as preservative and anti-caking agents. Despite their widespread usage, the products containing Ag-NP additives are a serious environmental and human health concern because of their toxicity. Studies on cell and bacterial cultures have shown that Ag-NPs are toxic; and the toxic effects are mainly due to the dissolved Ag ions when Ag-NPs degrade in water. In this study, considering the criteria outlined above, the purpose of the study and Ag-NPs were chemically synthesized in the laboratory environment and modified as chitosan coating. UV-Vis spectroscopy, transmission electron microscopy, scanning electron microscopy, X-ray crystallography and zeta potential analysis were used to characterize the silver nanoparticles.

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  AtıfWoS3·OpenAlex4·TR Dizin3

  İncele
• Kitap BölümüYalnız künye2021/r/munzur/3254
  Challenges, novel applications, and future prospects of chalcogenides and chalcogenide-based nanomaterials for photocatalysis

  Ates, Mehmet; Tanaydın, Mehmet Kayra; Yılmaz, Ersen

  Nanomaterials are composed of several atoms or molecules, which may be of various sizes and morphologies. Manmade nanomaterials are specially produced to take advantage of the unique properties of nanoscale. There are many metal chalcogenides with different structures and compositions such as CdSe, InAs, CdS, GaN, InGeAs, CdTe, PbS, PbSe, ZnS, Na2S, CaTe, Ti2S, and Cu2Se. The diversity of metal chalcogenides is related to the orbit of transition metals. In this chapter, new studies using chalcogenide compounds as photocatalysts were explained under the subtopics of metal chalcogenides and their properties, semiconductive nanostructures, nanomaterial production technique, chemical synthesis methods, and metal chalcogenides as photocatalysts. Novel applications of metal chalcogenide-based materials like water splitters, organic pollutant degraders, self-cleaning agents chalcogenide glasses and thermoelectric materials are explained in detail under the relevant headings. Future prospects of chalcogenides are also evaluated from a different perspective.

  AtıfScopus30·OpenAlex26

  İncele
• MakaleYalnız künye2020Scopus SJRQ2/r/munzur/3777
  Synthesis and modification of amine-terminated maleic anhydride‑butyl acrylate copolymer and investigation of adsorption properties for cadmium (II) ions (Cd2+)

  Yilmaz, Ersen; Erenler, Fatih Mehmet; Boztuğ, Ali

  In this study, a maleic anhydride‑butyl acrylate copolymer (MA-BA) was synthesized using maleic anhydride (MA) and butyl acrylate (BA) monomers. The synthesis was carried out in methyl ethyl ketone by benzoyl peroxide as the initiator at 70 °C. Secondly, the MA-BA copolymer was chemically modified with ethylenediamine and abbreviated as NH2MA-BA. The copolymer and its modified structure were analyzed spectroscopically by FT-IR, thermally by Thermo Gravimetry (TGA) and by Differential Scanning Calorimetry (DSC). Solubility tests of both structures were performed. Then, the adsorption of cadmium ions (Cd2+) by the modified copolymer (NH2MA-BA) was studied. The copolymer and its modified structure were synthesized successfully, and this was proven by their FTIR spectra. The (MA-BA) copolymer is soluble in common organic solvents but (NH2MA-BA) is not due to cross-linking. The DSC and DTA results showed that chemical modification improved the structure thermally. It was shown that the Freundlich model was the best explanation for the adsorption type in correspondence with the experimental plots, and the modified copolymer is a good candidate for Cd2+ adsorption.

  AtıfScopus8·WoS7·OpenAlex8

  İncele
• MakaleYalnız künye2018Scopus SJRQ3/r/munzur/4754
  SYNTHESIZING, CHITOSAN COATING AND DETECTING THE NANOTOXIC EFFECT OF THE LEAD SELENIDE (PbSe) QUANTUM DOTS

  Yilmaz, E.; Ates, M.; Sahilli, Y. C.

  Researches on nano-structured materials (<100 nm) are increasing rapidly in the direction of technological developments. Synthesis and modification of quantum dots, known as nanomaterials and nanocrystals, have become an important aspect of nanotechnology. The reason for this is that it has many potential applications in the field, including biomedicine and pharmacology. The unique properties and biological effects of nanostructured particles indicate that they can potentially be used as an alternative in the treatment of various diseases. In this work, PbSe quantum dots were synthesized by chemical method and modified by chitosan coating. The characterization of PbSe was done by TEM, SEM, XRD, DLS and Zeta potential analysis methods. When the morphological structures of the quantum dots obtained by chemical synthesis were examined, round and spherical nano-sized particles (<20 nm) of all PbSe were obtained according to TEM and SEM results. It has been seen that PbSe quantum dots have a positive (+) surface charge and are highly stable (40 + mV). In addition, the increase in oxidation resistance of PbSe coated with chitosan was found in XRD results. As a result of this research, small size and biopolymer coated and thus more stable quantum dots could be obtained. It has also been found that PbSe quantum dots coated with biopolymers like chitosan may have the potential to be used in pharmacology and biomedical applications.

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