Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2026Scopus SJRQ1Evaluation of electrical properties of poly(NIPA-co-St) composites containing neodymium and yttrium
Cetinkaya, Ebru; Karaaslan Ayhan, Nagihan; Torgut, Gulben
In this study, firstly, to obtain neodymium (Nd) and yttrium (Y)-containing composite materials, poly(N-isopropylacrylamide-copolymer-styrene) (poly(NIPA-co-St)) copolymer was synthesized by free radical polymerization method using N-isopropylacrylamide (NIPA) and styrene (St) monomers. Secondly, new composite materials were obtained by adding neodymium and yttrium to this copolymer at different weight ratios (10% and 20%). Structural and morphological characterizations of poly(NIPA-co-St) copolymer, poly(NIPA-co-St)-10%Nd, poly(NIPA-co-St)-20%Nd, poly(NIPA-co-St)-10%Y and poly(NIPA-co-St)-20%Y composite materials were carried out. The electrical properties of the copolymer and composite materials were evaluated by considering the frequency dependence of the dielectric constant (έ), dielectric loss (ε″) and electrical conductivity (σac) properties. At 100 Hz, the έ, ε″, and σac values of the copolymer were 5.12, 0.05, and 2.29 × 10−10 S/cm, respectively. With the addition of 10% Nd, the έ, ε″, and σac values at 100 Hz were calculated as 6.57, 0.10, and 1.79 × 10−9 S/cm, respectively, while with the addition of 20% Nd, these values were calculated as 8.39, 0.15, and 4.78 × 10−8 S/cm at 100 Hz. With the addition of 10% Y, the έ, ε″, and σac values at 100 Hz were calculated as 6.56, 0.053, and 1.81 × 10−9 S/cm, respectively, while with the addition of 20% Y, these values were calculated as 8.57, 0.0058, and 3.70 × 10−8 S/cm at 100 Hz. It can be stated that as the amount of Nd and Y additives to the poly(NIPA-co-St) copolymer increases, the έ, ε″, and σac values increase, indicating an improvement in electrical properties with the addition of Nd and Y elements.
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İncele - MakaleAçık Erişim2026Scopus SJRQ1Removal of Reactive Blue 4 Dye from Aqueous Solution with Magnetic Fe3O4@Nd/Alg Beads
Karaaslan Ayhan, Nagihan; Seker, Seda
In this study, magnetic iron oxide@neodymium/alginate (Fe3O4@Nd/Alg) beads were prepared by ionic crosslinking with neodymium (Nd) ions, then subjected to heat treatment, and for the first time, effective removal of Reactive Blue 4 (RB 4) dye from aqueous solution was achieved with these beads. For this purpose, ideal adsorption conditions that significantly affect the removal of this dye were determined. The ideal adsorption conditions were determined as pH:5, contact time (t):60 min, amount of magnetic Fe3O4@Nd/Alg bead (m):10 mg, initial RB 4 dye concentration (C0):25 mg/L, temperature (T): 25 °C. Adsorption isotherm, kinetic and thermodynamic studies were carried out under the ideal adsorption conditions. The adsorption data was found to completely follow Langmuir model for RB 4 dye and the maximum adsorption capacity of RB 4 was found to be 263.16 mg/g. The adsorption kinetic data was found to be compatible with pseudo-second order and adsorption processes were explained by intraparticle diffusion. In adsorption thermodynamics studies, it has been determined that the nature of the adsorption reaction is spontaneous, endothermic and with increasing randomness. Furthermore, reuse studies of magnetic Fe3O4@Nd/Alg beads were carried out and it was determined that these beads could be used successfully up to 10 adsorption/desorption cycles.
AtıfScopus4WoS4OpenAlex4İncele - MakaleAçık Erişim2025Scopus SJRQ3Cu, Fe, Mn AND Zn CONTENTS IN PROPOLIS SAMPLES FROM MALATYA, TÜRKİYE AND HEALTH RISK ASSESSMENT; [MALATYA, TÜRKİYE ARI PROPOLİSİNDEKİ CU, FE, MN VE ZN İÇERİKLERİ VE SAĞLIK RİSK DEĞERLENDİRMESİ]
Karaaslan Ayhan, Nagihan
In this study, copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) contents of propolis samples obtained from five different districts of Malatya, Türkiye were investigated. Element contents were determined using flame atomic absorption spectrometry (FAAS). The concentration ranges of propolis samples taken from five different districts of Malatya province varied between 1.24 ± 0.06 mg/kg and 6.28 ± 0.02 mg/kg for Cu, 206.28 ± 21.50 mg/kg and 663.08 ± 55.24 mg/kg for Fe, 15.40 ± 0.17 mg/kg and 27.11 ± 1.83 for Mn, 39.36 ± 1.82 mg/kg and 52.57 ± 2.13 mg/kg for Zn. The results obtained for each district and element were evaluated in detail considering the estimated daily intake (EDI), recommended dietary allowance (RDA), provisional maximum tolerable daily intake (PMTDI) of these elements for adults. Moreover, hazard coefficient (HQ) was calculated for risk assessment and it was determined that HQ values for the studied elements in bee propolis from all districts were below 1.
- MakaleYalnız künye2024Scopus SJRQ1Lanthanum-based magnetic biopolymers for brilliant green removal from aqueous solutions
Karaaslan Ayhan, Nagihan
In this study, lanthanum (La)-based magnetic biopolymers were synthesized, and the first adsorption study was conducted on the removal of brilliant green dye from aqueous water with these biopolymers. For the adsorption study, adsorption parameters were investigated and the ideal adsorption conditions determined for the removal of brilliant green dye from aqueous solutions are pH 11, t 60 min, m 10 mg, C0 25 mg/L, T 298 K. It was determined that the adsorption process was compatible with the single-layer Langmuir isotherm, and maximum adsorption capacity obtained according to the Langmuir isotherm was calculated as 256.41 mg/g. The adsorption process was found to be in accordance with the pseudo-second-order, and the adsorption process was explained by intra-particle diffusion. According to studies of adsorption thermodynamics, it has been established that the nature of the adsorption reaction is spontaneous, and this process is endothermic and has increasing randomness. Moreover, the reusability of magnetic lanthanum/alginate (La/Alg) biopolymers was investigated, and it was determined that the biopolymers could be used successfully. In summary, brilliant green dye has been successfully removed with simple, low-cost, environmentally friendly, and easily obtained magnetic La/Alg biopolymers. It can be stated that even low amounts of these biopolymers can be effective in the treatment of highly concentrated dye wastewaters.
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İncele - MakaleAçık Erişim2022Scopus SJRQ1Evaluation of Iron and Zinc Contents of Some Fish Species
Karaaslan Ayhan, Nagihan; Yaman, Mehmet
In this study, Fe and Zn contents in the muscle of different fish species (Engraulis encrasicolus, Trachurus trachurus, Mullus barbatus, Mugil cephalus, Pomatomus saltatrix, Dicentrarchus labrax, Scomber scombrus, Sparus aurata) were determined using flame atomic absorption spectrometry (FAAS). The highest Fe and Zn contents among studied fish species were found in Engraulis encrasicolus (7.13 ± 0.19 mg/kg) and Sparus aurata (11.00 ± 0.28 mg/kg). The lowest Fe and Zn contents were determined in Dicentrarchus labrax (3.12 ± 0.09 mg/kg) and Pomatomus saltatrix (5.50 ± 0.05 mg/kg). Moreover, the results were evaluated considering the estimated daily intakes (EDI) of these elements for adults. The estimated daily intakes were varied from 0.0101 to 0.0231 mg/kg bw/day for Fe and 0.0178 to 0.0357 mg/kg bw/day for Zn in fish species. In addition, the hazard quotient (HQ) and the hazard index (HI) values were calculated for risk assessment, and it was determined that these values were below 1 for fish species.
AtıfScopus10WoS8OpenAlex9İncele - MakaleYalnız künye2022Scopus SJRQ3Characterization of the antioxidant activity, total phenolic content, enzyme inhibition, and anticancer properties of Achillea millefolium L. (yarrow)
Karaaslan Ayhan, Nagihan; Karaaslan Tunc, Merve Goksin; Noma, Samir Abbas Ali; Kurucay, Ali; Ates, Burhan
The antioxidant activity, total phenolic content, enzyme inhibition, anticancer properties of Achillea millefolium L. (yarrow), which is generally consumed by humans as herbal tea, were investigated. Yarrow extracts were prepared with different extraction techniques and solvents and the optimum conditions were determined. When the antioxidant activity and total phenolic content results were evaluated, the best yield was obtained with ultrasound-assisted extraction for all solvents. Moreover, the yields from highest to lowest were methanol, water, and acetonitrile. The enzyme inhibition and anticancer of Achillea millefolium L. extracts using methanol were evaluated. The IC50 values for the inhibition of xanthine oxidase and acetylcholinesterase were 4.974 ± 0.54 and 21.891 ± 1.118 µg/mL, respectively. The extract concentration was determined to be 23.85 μg/mL for 50% reduction in growth inhibitory activity cell viability (IC50) against breast cancer (MCF-7).
AtıfScopus7OpenAlex9İncele - MakaleYayıncıda açık erişim2021Scopus SJRQ2Investigation of antioxidant properties of chamomile consumed as herbal tea
Karaaslan Ayhan, Nagihan
Common chamomile is consumed as herbal tea due to its antioxidant properties and biological activities in daily life. In this study, antioxidant activities and total phenolic contents of white and yellow chamomiles were investigated in terms of extraction methods and solvent types. In all extraction methods used for extraction of both chamomiles, the best antioxidant activity and total phenolic results were obtained with water extracts. Also, the best yield was found with sonication-assisted stirring for both chamomile extracts obtained using three extraction solvents. DPPH and ABTS radical scavenging activities obtained by sonication-assisted stirring for water extracts were 10.886 ± 0.244 mg TEAC/g and 8.702 ± 0.567 mg TEAC/g for white chamomile, and 11.709 ± 0.693 mg TEAC/g and 11.139 ± 0.514 mg TEAC/g for yellow chamomile. The total phenolic contents were determined as 3.863 ± 0.325 mg GAE/g for white chamomile and 5.225 ± 0.417 mg GAE/g for yellow chamomile. Novelty impact statement: In this study, the antioxidant properties of white and yellow chamomile were examined in detail in terms of different extraction methods and solvent types. Sonication-assisted stirring and water were determined to be the best extraction method and solvent for both chamomiles. According to the results, it can be stated that chamomile has higher antioxidant properties than white chamomile under the best extraction conditions.
AtıfScopus9WoS9OpenAlex8İncele - MakaleYalnız künye2021Scopus SJRQ1Development of comprehensive liquid chromatography with diode array and mass spectrometric detection for the characterization of (poly-)phenolic and flavonoid compounds and application to asparagus
Karaaslan Ayhan, Nagihan; Rosenberg, Erwin
The main objective of the present work was to develop a method for the simultaneous and comprehensive analysis of (poly-)phenolic and flavonoid compounds with liquid chromatography with diode array and mass spectrometric detection and its application to green asparagus samples. To this end, a representative set of polyphenols was used to develop the method. A through method validation was carried out with these. The method was applied to asparagus samples known as a healthy vegetable being rich in bioactive compounds. Polyphenol contents of asparagus samples were determined by carrying out quantitative and qualitative analyses by LC-DAD-ESI/MS. In this context asparagus sample extracts were obtained using solvents of different polarity. The results were evaluated statistically and showed that rutin is the major phenolic compound in asparagus. This demonstrates the versatility of this rapid and sensitive method for the simultaneous analysis of (poly-)phenolic and flavonoid compounds which was successfully applied to asparagus samples.
AtıfScopus15WoS15OpenAlex17İncele
