PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collections

Permanent URI for this collectionhttps://hdl.handle.net/20.500.13091/5

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Now showing 1 - 8 of 8

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: 8
Citation - Scopus: 7
Fluorescence Switchable Sensor Enabled by a Calix[4]arene-Cu(ii) Complex System for Selective Determination of Itraconazole in Human Serum and Aqueous Solution
(Elsevier, 2022) Akceylan, Ezgi; Erdemir, Serkan; Tabakçı, Mustafa; Sivrikaya, Abdullah; Tabakçı, Begüm
A switchable fluorescence sensor based on a calix (Monapathi et al., 2021) [4]arene:Cu2+ complex (FLCX/Cu) has been developed for the detection of itraconazole (ITZ) with high sensitivity and specificity. For the devel-opment of the sensor, the selective complexation of a fluorescent calix (Monapathi et al., 2021) [4]arene de-rivative (FL-CX) with the Cu2+ ion causing fluorescence quenching was utilized. In addition, the sensor properties of the FLCX/Cu prepared were investigated. For this purpose, various substances (selected anions, cations, and drugs) with which ITZ can be found together were studied in an aqueous solution. Limit of detection (LOD) and limit of quantification (LOQ) values were determined in the range of 1.00-60.0 mu g/L as 3.34 mu g/L and 11.1 mu g/L for ITZ, respectively. Moreover, the real sample analyses were performed in human serum and tablet form. Furthermore, the effect of some possible serum contents on sensor performance was also studied. All these studies confirmed the development of a simple, precise, accurate, reproducible, highly sensitive, and very stable fluorescence sensor.
Citation - WoS: 8
Citation - Scopus: 8
Fruit Peel Incorporated Alginate Based Magnetic Hydrogel Bio-Composite Beads for Removal of Hexavalent Chromium
(Elsevier, 2025) Parlayici, Serife; Baran, Yaprak
High adsorption capacity, reusability and sustainability are the most important features sought in the adsorbent preferences to be used in wastewater treatment. In this research work, magnetic composite beads prepared from fruit peels (nectarine and orange) and alginate (ALG) as biopolymers (NAF and OAF) were synthesized by dropping and pH-precipitation method as alternative adsorbents. By encapsulating the adsorbent using alginate and imparting magnetic properties, the separation of the adsorbent from water after the adsorption process has been simplified. Fourier transform infrared spectroscopy analysis (FTIR), scanning electron microscopy (SEM) analysis, energy-dispersive X-ray (EDX)-mapping and X-ray diffraction (XRD) analyses were performed to examine the surface chemical structure and surface morphological structure of these new synthesized biosorbents. The calculated maximum adsorption capacities were 224.3 mg/g for OAF and 256.5 mg/g for NAF at 298 K and pH =2.0. It was observed that the adsorption process for both adsorbents was endothermic and spontaneous. Moreover, the adsorptions of Cr (VI) onto both adsorbents followed the pseudo-second order model and fit the Langmuir isotherm model better. OAF and NAF were found to be reusable with stable adsorption capacity for at least five cycles. Overall, this study demonstrates the performance of OAF and NAF in the removal of Cr (VI) ions from aqueous solutions, thus highlighting the promising potential of these magnetic bio-based adsorbents for sustainable water treatment.
Citation - WoS: 32
Citation - Scopus: 37
Impact of Land Consolidation on Agricultural Decarbonization: Estimation of Changes in Carbon Dioxide Emissions Due To Farm Transport
(Elsevier, 2023) Janus, Jaroslaw; Ertunc, Ela
Areas used for agriculture are a large source of carbon emissions, but there is great potential for reducing them. Land consolidation, through the comprehensive reorganization of the spatial arrangement of farms, can reduce emissions as a result of reducing fuel consumption. The subjects of this study are the veracity of this statement and the scope of var- iation in the potential reduction of carbon emissions. The analysis covered six land consolidation projects in Poland and Turkey, for several agricultural models that differ in the level of fuel consumption.Changes in agricultural road layout resulting from the implementation of land consolidation projects and changes in the number of farm plots and their spatial distribution were considered. The study considered several different levels and structures of fuel consumption on farms. The applied methodology is based on analysis of changes in distance to fields resulting from land consolidation projects, which are then expressed as changes in fuel consumption.The obtained emission reduction results for the studied land consolidation projects were diverse and range from 0.3 to 170 kg CO2/ha/year. The reduction in fuel consumption on farms at the level of individual villages reached a maxi- mum of 32 %, while the average value of this reduction in the entire surveyed set was 12.5 %. The proposed approach increases the accuracy of existing methods for estimating the long-term balance of carbon emissions and carbon accumulation related to the implementation of land consolidation projects. The observed emis- sion reduction values can be considered a significant economic and ecological effect because the effects of these pro- jects persist for at least several decades.
Citation - WoS: 13
Citation - Scopus: 15
Machine Learning-Based Approach for Efficient Prediction of Toxicity of Chemical Gases Using Feature Selection
(Elsevier, 2023) Erturan, Ahmet Murat; Karaduman, Gül; Durmaz, Habibe
Toxic gases can be fatal as they damage many living tissues, especially the nervous and respiratory systems. They can cause permanent damage for many years by harming environmental tissue and living organisms. They can also cause mass deaths when used as chemical weapons. These chemical agents consist of organophosphates, namely ester, amide, or thiol derivatives of phosphorus, phosphonic or phosphinic acids, or can be synthesized independently. In this study, machine learning models were used to predict the toxicity of chemical gases. Toxic and non-toxic gases, consisting of 144 gases, were identified according to the United States Environmental Protection Agency, Occupational Safety and Health Administration, and the Centers for Disease Control and Prevention. Six machine-learning models were used to predict the toxicity of these chemical gases. The per-formance of the models was verified through internal and external validation. The results showed that the model's internal validation accuracy was 86.96% with the Relief-J48 algorithm. The accuracy value of the model was 89.65% with the Bayes Net algorithm for external validation. Our results reveal that identifying the toxicity of existing and potential chemicals is essential for the early detection of these chemicals in nature.
Citation - WoS: 7
Citation - Scopus: 8
Methylene Blue Sorption Performance of Lignocellulosic Peach Kernel Shells Modified With Cellulose Derivative Chitosan as a New Bioadsorbent
(Elsevier, 2024) Soydal, Ülkü; Kocaman, Suheyla; Ahmetli, Gulnare; Avsar, Semra
In this study, adsorption isotherms (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich) and thermodynamic properties of cationic methylene blue (MB) dye adsorption onto chitosan-coated peach kernel shell waste (CTS-PKSh) from wastewater were investigated. CTS was cross-linked with citric acid (CA) and glutaraldehyde (GA). The adsorbents were characterized by FE-SEM/EDS, FTIR, and particle size distribution. MB adsorption behavior onto the biosorbents was investigated concerning parameters such as adsorbent dosage (0.8-8 g/L), time (0-540 min), pH (3-10), initial dye concentration (50-700 mg/L), and temperature (25-55 degrees C). The Langmiur q(max) and experimentally q(e) MB adsorption capacities of the new adsorbents were found to be 227.27 and 201 mg/g for CA cross-linked CTS-PKSh (CA@CTS-PKSh) and 111.12 and 96.5 mg/g for GA cross-linked CTS-PKSh (GA@CTS-PKSh), respectively. The results of thermodynamic analysis showed that adsorption was feasible, exothermic, and spontaneous. According to adsorption and recyclability results, CA@CTS-PKSh was more effective for MB removal at a 2 g/L adsorbent dose for an initial dye concentration of 100 mg/L, 25 +/- 1 degrees C, contact time 60 min, and pH 7.
Citation - WoS: 1
Citation - Scopus: 2
Sustainable Biobased Composites: Fumaric Acid-Based Epoxy Resin Synthesis and Modified Natural Waste Reinforcements
(Elsevier, 2025) Kocaman, Suheyla; Ahmetli, Gulnare; Ozmeral, Nimet
The increasing demand for sustainable alternatives to petroleum-based polymers has accelerated the development of biocomposites to mitigate environmental impact. In this study, a novel bio-based epoxy resin (EFA) was synthesized via the reaction of fumaric acid (FA) and epichlorohydrin (ECH), and characterized using FT-IR, 1H NMR, viscosity, mass spectrometry, and epoxy group analysis. Apricot kernel shell (APKSh), an agricultural waste, was used as a natural reinforcement, modified with citric acid (CA) and levulinic acid (LA) to improve interfacial compatibility. Composites were produced with filler contents ranging from 5 to 30 wt% and tested for FT-IR, SEM, TGA, DMA, mechanical, thermal, and surface properties. The 15 wt% CA-modified composite exhibited a tensile strength of 105.7 MPa, an elastic modulus (e-modulus) of 8.7 GPa, and a Shore D hardness of 80, representing up to 222 % improvement in tensile strength and 107 % improvement in hardness compared to the neat ER-EFA (7:3 weight ratio). The LA-APKSh composites showed a char residue of 26.9 % at 800 degrees C and a Tg value of 106.01 degrees C. Contact angle (C.A.) measurements revealed enhanced hydrophobicity, with values exceeding 99.6 degrees for CAAPKSh composites. The weight gain data in seawater indicated that all composites had higher values compared to the neat ER-EFA matrix (7:3 weight ratio). ANOVA analysis highlighted the influence of filler type and content on composite properties. This study presents a promising approach to developing high-performance, eco-friendly epoxy composites using chemically modified lignocellulosic waste.
Citation - WoS: 8
Citation - Scopus: 8
Use of Ultrasonic Treatment as a Pre-Phase in the Shear Flocculation Process
(Elsevier, 2023) Özkan, Alper; Eşmeli, Kiraz
The use of ultrasonic energy has mostly been investigated for the flotation process in mineral processing, but its application to flocculation with collectors is extremely limited. Therefore, in this study, the effect of ultrasound in the shear flocculation technique, was intended to be revealed by using a celestite sample. The initial studies carried out for this purpose showed that in the absence of any reagent, the ultrasonication decreased the surface charge of the mineral, which caused the coagulation of the celestite suspension. In this scope, the short application of ultrasound at high power (i.e., 2 min batch regime and 150 W) provided a more positive effect. In the flocculation process carried out with collectors, the use of ultrasonic energy as a pre-phase for the suspension enhanced the aggregation of celestite particles. This result also fits well with the rise in the contact angle and the decrease in the zeta potential of the mineral due to the ultrasound. However, when the ultrasound was applied directly to the flocculation phase (ultrasound-induced flocculation only), the aggregation of celestite particles was affected adversely. Consequently, it can be said that in the shear flocculation process, the ultrasonic treatment should be used as a pre-phase for mineral suspensions. In this case, the flocculation of fine mineral particles in suspensions with surfactants can be improved by ultrasonic processing.

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