Yazarlar
- Tozlu, Alperen(15)
- Kul, Sinan(13)
- Kutlu, Naciye(12)
- Cuce, Erdem(8)
- Cuce, Pinar Mert(8)
- Uçurum, Metin(8)
- Gökçe, H.S.(7)
- Kamiloğlu, Aybike(7)
- Özahi, Emrah(6)
- Şahin, Engin(6)
- Ayata, Ümit(5)
- Ecem Bayram, Nesrin(5)
- Ekmekyapar Torun, Fatma(5)
- Guclu, Tamer(5)
- Gökçe, H. Süleyman(5)
- Serencam, Huseyin(5)
- Yilmaz, Fatih(5)
- Özdemir, Akın(5)
- Bayram, Sinan(4)
- Cengiz, Ibrahim(4)
- Elbir Abca, Tuğba(4)
- Gerçek, Yusuf Can(4)
- Gökçe, H. S.(4)
- Karbancioglu-Guler, Funda(4)
- Mercan, Emin(4)
- Serencam, Hüseyin(4)
- Sert, Durmuş(4)
- Teke, Çağatay(4)
- Torun, Fatma Ekmekyapar(4)
- Tozlu, A.(4)
- İrdemez, Şahset(4)
- Abusoglu, Aysegul(3)
- Abuşoğlu, Ayşegül(3)
- Baştürk, Fatma Nur(3)
- Bingül, Züleyha(3)
- Can, Zehra(3)
- Duran, Celal(3)
- Kamiloğlu, Hakan Alper(3)
- Karakaş, İbrahim Hakkı(3)
- Kırkıncı, Seran(3)
Yayınlar
- Derleme MakaleAçık Erişim2025Digitalization and Sustainability Conflict in Society: Waste Culture and Green Consciousness
Kizmaz, Nuran
Sustainability, which is based on the protection of the resources we have within the framework of the global climate crisis, is gaining importance day by day. With the industrial revolution, we see that the daily lives of individuals have become integrated with technology. It is seen that all institutions of society, from communication to economy, from education to politics, have become connected to technology and networks. Thus, the concepts of increasing digitalization and sustainability have become synonymous with each other. In this article, the relationship between the two concepts will be analyzed in a social and environmental context, and their positive and negative aspects will be discussed. This study aims to understand and evaluate the conflict between wasteful culture and green consciousness by addressing the societal implications in the relationship between digitalization and sustainability. By examining how digital technologies have the potential to provide environmental benefits but also how they affect environmental threats such as e-waste, the study aims to reveal the societal consequences arising from this dilemma. Thus, the main question of the research will be tried to be answered whether digitalization provides environmental benefits in line with sustainability goals or deepens the e-waste crisis by triggering a culture of waste. In the research, a literature review will be conducted from qualitative research methods. As a result, inferences will be made on the future potential of sustainable digital technologies by drawing attention to the awareness of the balance between digitalization and green consciousness.
- MakaleAçık Erişim2025Öğretmen Adaylarının Sürdürülebilir Tüketim Davranışları İle Su Okuryazarlık Düzeyleri Arasındaki İlişkinin İncelenmesi
Degirmenci, Yavuz; Bayramoglu, Turgut
Doğal kaynakların sınırsız olmadığı bir dünyada kaynakların bilinçli, dengeli ve gelecek nesiller için de kullanılabilir olması önemlidir. Nitekim artan dünya nüfusu, değişen koşullar, yaşam tarzları ve bireylerin tüketim davranışları kaynakların sürdürülebilir kullanımını zorunlu hale getirmiştir. Dolayısıyla kaynakların etkili, verimli ve gelecek nesiller için sürdürülebilir kullanılması konusunda bireylerin ve toplumu oluşturan bütün paydaşların çeşitli sorumlulukları olduğu açıktır. Bununla birlikte bireylerin küçük yaşlardan itibaren bu konuda eğitilmesi, bilinçlendirilmesi ve farkındalıklarının artırılması kaynakların sürdürülebilir kullanımı açısından hayati öneme sahiptir. Bu araştırmanın amacı öğretmen adaylarının sürdürülebilir tüketim davranışları ile su okuryazarlıkları arasındaki ilişkiyi incelemektir. Araştırmada nicel yaklaşımlarda yaygın olarak kullanılan ilişkisel tarama modeli kullanılmıştır. Verilerin toplanmasında “sürdürülebilir tüketim davranışı ölçeği ve “su okuryazarlığı ölçeği” kullanılmıştır. Verilerin analizinde ise t testi, ANOVA ve korelasyon analizleri kullanılmıştır. Araştırmanın katılımcıları, 2023-2024 eğitim- öğretim döneminde Türkiye’de bir devlet üniversitesinin eğitim fakültesinde öğrenim gören 145 kadın ve 70 erkek öğretmen adayından oluşmaktadır. Araştırma sonuçlarına göre; cinsiyet, sınıf düzeyi, bölüm, ebeveyn eğitim durumu ve yaşanılan yer değişkenlerine göre anlamlı farklılık oluşmazken, katılımcıların sürdürülebilir tüketim davranışları ile su okuryazarlıkları arasında yüksek düzeyde pozitif ilişkinin (r = .628; p<.01) olduğu tespit edilmiş ve çeşitli önerilerde bulunulmuştur.
AtıfOpenAlex5TR Dizin3
İncele - MakaleAçık Erişim2025Scopus SJRQ4Karpuz atıkları ve karpuz suyu ile zenginleştirilmiş tam buğday ekmeği üretimi ve duyusal özelliklerinin değerlendirilmesi
Cebeci, Fatma; Vergili, Samet; Karaman, Mustafa
Ekmek, ülkemizde beslenme açısından önemli yer tutan, fazla tüketilen bir gıdadır. Bu nedenle ekmeğin zenginleştirilmesiyle besleyici değerinin artırılması üzerine çalışmalar, halkımızın sağlıklı ve dengeli beslenebilmesi açısından önemlidir. Karpuz, gıda endüstrisinde işlenmesi sırasında %30-41 kısmının kabuk ve %2’lik kısmının ise çekirdek yan ürünü açığa çıkaran bir meyvedir. Bu çalışmada karpuz atıklarının ve karpuz suyunun ekmeğin zenginleştirilmesinde kullanılmasıyla biyoaktif özelliği iyileştirilmiş ekmek üretimi hedeflenmiştir. Üretilen ekmek, kontrol tam buğday ekmeğiyle karşılaştırılmıştır. Duyusal analiz sonuçlarına göre kontrol tam buğday ekmeğiyle (KE) karşılaştırıldığında karpuz atıkları ve karpuz suyu ile zenginleştirilmiş ekmeğin (KAZE) renk, koku, gözenek yapısı, tekstür, çiğnenebilirlik, lezzet ve genel beğeni açısından farklı bulunmadığı gözlenmiştir (t testi, p>0.05). Toplam fenolik madde içeriği açısından kuru örneğin gramı başında KAZE ve KE örneklerinde sırasıyla 0.860.02 mg gallik asit eşdeğer cinsinden (GAE) ve 0.430.01 mg GAE değerleri bulunmuştur. Sırasıyla KAZE ve KE kuru örneklerinin gramı başına DPPH metodunda; 0.400.04 mg askorbik asit eşdeğeri (AAE) ve 0.300.04 mg AAE, ABTS metodunda; 1.130.05 mg AAE ve 0.620.02 mg AAE değerleri saptanmıştır. Sonuçlar KAZE örneğinin toplam fenolik madde ve antioksidan aktivite değerleri açısından KE örneğinden daha zengin olduğunu göstermektedir (p
- MakaleAçık Erişim2025Optimization and Mechanical Performance of Alkali-Activated Bottom Ash and Polypropylene Fiber in Deep Mixing Columns
Yilmaz, Fatih; Kamiloğlu, Hakan Alper; Avlayan, Büşra
Deep mixing columns (DMC) are one of the widely used soil improvement methods in cohesive and cohesionless soils. Cement and lime are predominantly used as conventional binders in DMC grout. Due to high CO2 emissions from conventional binders, the feasibility of using alkali-activated binders as DMC grout is being investigated. This study was conducted in three main stages. In the first stage, the proportions of bottom ash and activator (mixture of 10M NaOH and Na2SiO3) were optimized to achieve the highest UCS value using response surface methodology (RSM). In the second stage, the influence of polypropylene fiber content was examined in detail by incorporating varying amounts of fibers into the optimized binder-activator mixture to determine the optimal fiber content. Since DMC are fully buried, they are cured in the soil media. In this case, the soil temperature, which varies along the depth of the soil, also becomes the curing temperature of the DCM. Due to climate, soil condition and thermodynamic based parameters, curing temperature of the DMC varies throughout the soil depth. Therefore, in the third stage, the effect of curing temperature on the mechanical properties of the stabilized samples was evaluated under different temperatures. Results of the study revealed optimal UCS values with AAB content of 0.3-0.5 and activator content of 0.45-0.5. Polypropylene fiber reinforcement further improved strength, reaching an optimum at 1.50-1.75% content. Curing temperature played a significant role, with UCS and modulus of elasticity increasing up to 30 °C, indicating the importance of considering environmental factors in DMC design. These findings suggest that the optimized mixture has the potential to replace conventional cement-based binders in DMCs, offering a more sustainable solution with lower carbon emissions. Furthermore, the observed influence of curing temperature highlights the need to account for subsurface thermal variations when designing DMCs, as these factors significantly affect strength gain and long-term performance.
- MakaleAçık Erişim2025Scopus SJRQ1Energy, exergy and economic optimization application of integrated dual-loop organic rankine cycle: A case of shopping mall power plant
Topcu, Muhammed Taha; Tozlu, Alperen; Bilen, Kadir
This paper presents a thermoeconomic analysis of the Dual-Loop Organic Rankine Cycle (DORC) integrated into the Erzurum Mall Power Plant (EMPP). The DORC system is designed to utilize waste heat at 425 degrees C and 9 kg/s, producing additional power for the existing plant. The integration of dual-loop ORC systems with different critical temperature fluids into an operational facility is analyzed. High-temperature cycles use working fluids such as Toluene, MDM (octamethylcyclotrisiloxane), n-Nonane, and n-Octane, while refrigerants R236fa, R600a, and R124 are employed in the low-temperature cycles. The designed model demonstrates that up to 11.4 % of the plant's existing capacity can be added as extra power. The Toluene/R600a combination is identified as the best fluid pair, delivering the highest total net power output (653.4 kW), the lowest total cost rate (19.18 $/h), and the highest exergy efficiency (20.18 %). Optimization of the DORC system is performed using the NSGA-II in MATLAB. For the toluene/R600a pair, the optimization results show an increase of 13.52 % in the net power output and decrease of 1.48 % in the total cost rate, which is a significant improvement over the initial results.
AtıfWoS3OpenAlex1
İncele - MakaleAçık Erişim2025EFFECT OF SCRAP RATIO ON LIQUID METAL QUALITY OF LOW-PRESSURE DIE-CASTING (LPDC) ALLOY USING ROTARY DEGASSING
Tokatli, Mehmet; Çolak, Murat; Yüksel, Caglar
Although various processes are used in aluminum liquid metal cleaning, environmentally friendly, economical and applicable methods should be preferred in industry. Among these methods, the Density Index test based on the reduced pressure test (RPT), which is widely used to measure the efficiency of the rotary degassing process, and the K-mold test method, which offers fast and practical results were carried out. The effects of rotary degassing method on the liquid metal quality of AlSi7Mg0.3 (A356) aluminum alloy charges prepared with different proportions of scrap and ingots were evaluated using a constant 5l/min gas flow rate, a constant 5 min process time and a constant 300 rpm rotor rotation speed. The results show that the Density Index values can be reduced from 1.48% to around 0.74% with increasing scrap rate, while K-mold values can be reduced from 2.8 to 0.6. It was also shown that the rotary degassing method is effective in liquid metal cleaning, and the K-mold test can be used as a very practical control tool for evaluating liquid metal quality.
- MakaleAçık Erişim2025Scopus SJRQ2Life cycle cost and carbon footprint analysis of CuO–Al2O3/water hybrid nanofluids in thermoelectric vaccine refrigerators
Cuce, Pinar Mert; Guclu, Tamer; Cuce, Erdem
This study investigates the application of a CuO–Al2O3/water hybrid nanofluid as a coolant in thermoelectric vaccine refrigerators, aiming to enhance heat dissipation from the Peltier module’s hot side. A 35-L cooling cabinet was utilised, and experimental comparisons were made using water and a 2% CuO–Al2O3/water hybrid nanofluid. Results show that the vaccine cabinet reaches the target temperature of 4 °C in 990 s with nanofluid, compared to 1200 s with water. The system’s energy consumption was reduced by 18.3%, and carbon emissions decreased by 12.3% over a 15-year lifespan, highlighting its environmental benefits. Despite similar coefficients of performance (COP), the nanofluid system demonstrates enhanced efficiency, shorter cooling times, and long-term sustainability advantages. These findings support the adoption of hybrid nanofluids in thermoelectric cooling applications for energy-efficient and environmentally friendly refrigeration systems.
AtıfScopus6WoS6OpenAlex8
İncele - MakaleYalnız künye2025Scopus SJRQ2Optimized ultrasonic-NaDES extraction of anthocyanins, polyphenolics, and organic acids from chokeberry fruit with blueness and antimicrobial evaluation
Gerçek, Yusuf Can; Kutlu, Naciye; Çelik, Saffet; Bayram, Sinan; Kırkıncı, Seran; Ecem Bayram, Nesrin
Deep eutectic solvents (DESs) have been widely used in food processing in recent years, owing to their remarkable advantages. The aim of this study was to evaluate the potential of DESs for the recovery of bioactive components from chokeberry fruit. First, among the 10 different DESs, the DES that extracted the highest total individual phenolic content (TIPC) from chokeberry was determined. Then, ultrasonically assisted extraction conditions (ultrasonic amplitude, time, and temperature) were optimized by response surface methodology to obtain the maximum amount of TIPC using this DES. According to the results obtained, the natural deep eutectic solvent (NaDES) choline chloride: acetic acid (1:2, 30% water content) provided the highest yield for TIPC extraction and the optimum conditions for maximum TIPC extraction were determined as 100% for ultrasonic amplitude, 50 °C for temperature and 60 min for sonication time. The TIPC content of the extracts prepared with this NaDES was determined between 1740.26 and 3703.14 mg/kg. In addition, the individual organic acid and individual anthocyanin contents of the NaDES extracts, as well as their antioxidant and antimicrobial activities, were determined. Chlorogenic acid (1392.351–2361.48 mg/kg) among phenolic compounds, pyruvic acid (9361.35–47398.04 mg/kg) among organic acids and kuromanin chloride (69748.13–134668.24 mg/kg) among anthocyanins were the dominant compounds in NaDES extracts. However, the extracts showed varying levels of antimicrobial activity against Gram (+) bacteria, Gram (−) bacteria, and yeast-like fungi (Candida strains). Finally, the Blue Applicability Grade Index (BAGI) was used to evaluate the practicality/blueness potential of the chromatographic method used to determine the anthocyanin composition of the DES extracts. In conclusion, NaDES (choline chloride:acetic acid) can be an alternative solvent for the recovery of some individual phenolics, organic acids and anthocyanins under different extraction conditions. In addition, the use of NaDES in the recovery of various functional compounds needed in food, cosmetics, pharmaceuticals, etc., is important for the promotion of sustainability and green technology.
AtıfScopus19WoS18OpenAlex19İncele - MakaleYalnız künye2025Scopus SJRQ1Eco-friendly reduction of graphene oxide using urea: An optimized approach for high-performance rGO
Ucuncuoglu, Didar; Bektaş, Enes; Karakaş, İbrahim Hakkı; Amin Bhuiyan, Mohammad Ruhul; Korucu, Haluk
The growing demand for environmentally friendly and cost-effective approaches has accelerated the development of sustainable methods for the synthesis of reduced graphene oxide (rGO). In this study, urea was utilized as a green reducing agent for rGO synthesis, offering an alternative to conventional toxic chemicals. The synthesized rGO was comprehensively characterized using FTIR, SEM-EDS, Raman spectroscopy, XRD, BET analysis, zeta potential, and conductivity measurements. These analyses revealed key functional, structural, and morphological properties, including surface functional groups, elemental composition, carbon-to-oxygen (C/O) ratio, particle size (PS), crystallite size (CS), specific surface area (SSA), zeta potential (ZP), thermal conductivity (TC), and electrical conductivity (EC). Process optimization was performed using the Taguchi L4(23) orthogonal array design across nine quality parameters. Under optimal conditions, notable enhancements were achieved: C/O ratio increased by 108%, ID/IG ratio by 164%, I2D/IG ratio by 26%, CS by 75%, and SSA by 134%, while PS was reduced by 37%. Furthermore, ZP and TC increased by 58% and 33%, respectively, whereas EC was reduced by 97%. These findings demonstrate the potential of urea as a sustainable and effective reducing agent in the production of high-performance rGO materials.
AtıfScopus3WoS3OpenAlex3İncele - MakaleAçık Erişim2025Scopus SJRQ1Artificial neural network modelling of reactive red 45 Azo dye removal by peroxi-electrocoagulation
Bayar, S.; Erdoğan, M.; Taşdemir, A.; Kaleli, A.; Paloluoglu, C.
In the present study, the Peroxi-electrocoagulation process was employed to remove chemical oxygen demand and the decolorization of reactive red 45 dye wastewater. This process offers several advantages, including the oxidation of dye molecules by hydroxyl radicals and coagulation through iron hydroxide precipitation. The reactor was equipped with six iron electrodes, providing a total surface area of 546 cm2. The effects of applied current (0.3–0.18 A), hydrogen peroxide concentration (100–700 mg/L), initial pH (2.5–5.0), and dye concentration (100–500 mg/L) on chemical oxygen demand and color removal were investigated. Optimum operational conditions were determined to be applied current of 0.150 (corresponding to current density of 0.27 mA/cm2), pH of 3.0, H2O2 concentration of 600 mg/L, and dye concentration of 200 mg/L. Under these conditions, COD and color efficiencies reached 83% and > 99%, respectively. The specific energy consumption under optimal conditions was 33.4 kWh/kg COD with 82.8% COD removal. The findings indicate that increasing the applied current and H2O2 concentration enhances removal performance up to a certain threshold, beyond which no significant improvement is observed. This suggests that the availability of electrogenerated reagents governs the overall reaction efficiency. Additionally, an artificial neural network model was developed to predict COD and color removal efficiencies. The network employed a 4:10:2 architecture and was trained using a backpropagation algorithm. Input variables included applied current, pH, H2O2 concentration, and dye concentration. The model exhibited high predictive accuracy, with R2 of 0.9782 for COD removal and 0.9579 for Color removal, confirming the effectiveness of the ANN in modeling.
AtıfScopus3WoS3OpenAlex4İncele - MakaleYalnız künye2025Scopus SJRQ1Extraction of Bioactive Compounds from Celery Root Peels Using an Ultrasound-Assisted Method with Choline Chloride–Based Deep Eutectic Solvents
Kamiloğlu, Aybike; Kutlu, Naciye; Elbir Abca, Tuğba; Yılmaz, Özlem
The concepts of sustainable and green technology have come to the forefront due to problems such as increasing environmental pollution, depletion of resources, and uncontrolled increases in industrialization. Green chemistry aims to reduce or completely eliminate pollution in the environment. In this study, both the ultrasonic method, which is a form of green technology, and deep eutectic solvents, which are among green solvents, were used, and a perspective on creating economic value from a waste product (celery root peel) is presented. In this context, phytochemical compounds (total flavonoid content and antioxidant activities) were obtained from celery root peels by ultrasonic-assisted extraction using 10 different choline chloride–based deep eutectic solvents, and the results were compared with methanol, an organic solvent. As a result, according to the total flavonoid content, the most effective deep eutectic solvent was choline chloride to sucrose, while according to the antioxidant activity value, choline chloride to lactic acid was found to be effective. For all of the analyzed bioactive compounds, higher or equal yields were obtained with all deep eutectic solvent extracts compared to methanol, and deep eutectic solvents could be alternatives to organic solvents (such as methanol) that may have toxic effects on humans or the environment.
AtıfScopus9WoS9OpenAlex10İncele - MakaleAçık Erişim2025Scopus SJRQ2Extraction of Phenolic Compounds From Lavender (Lavandula angustifolia L.) Plant by Natural Deep Eutectic Solvent and Greenness Assessment of Analytical Method With Modified Green Analytical Procedure Index
Ecem Bayram, Nesrin; Yenigün, Baran; Gerçek, Yusuf Can
In recent years, it has been important in terms of green technology and sustainability to promote the use of natural deep eutectic solvents (NADESs), especially those based on natural products, for the extraction of bioactive components with different functional properties from foods. Therefore, in this study, the effects of green extraction technology (ultrasonic-assisted extraction) and green solvents (NADESs) on the recovery of bioactive components from lavender (Lavandula angustifolia L.) were investigated and evaluated. In addition, the degree of greenness of the analytical method used during the study was determined using the modified green analytical procedure index (MoGAPI). In this context, the total phenolic content (TPC), total antioxidant capacity, and individual polyphenolic profiles of lavender extracts prepared with two different NADES were investigated by liquid chromatography-tandem mass spectrophotometer. Based on the results obtained, it was determined that NADES formed with choline chloride:formic acid (ChCl:FA) had a higher potential to extract bioactive components from lavender than NADES formed with ChCl:ethylene glycol (ChCl:EG). The TPC, antioxidant capacity, and total individual polyphenolic compound content of lavender extracted with these NADES were determined as 9.76 mg gallic acid equivalent/g, 20.83–104.39 mg Trolox equivalent/g, and 200.835 mg/kg, respectively. However, the degree of greenness determined by the MoGAPI tool of the analytical method used in this study was 78% and classified as ‘excellent green’. As a result, it can be concluded that NADES formed with ChCl:FA can be an alternative to conventional solvents for the extraction of bioactive components from lavender, as it provides a remarkable recovery of bioactive substances.
AtıfScopus5WoS4OpenAlex3
İncele - MakaleYalnız künye2025Scopus SJRQ2Influence of ultrasonic-assisted deep eutectic solvent extraction on bioactive compounds from germinated mung beans (Vigna radiata) and greenness assessment
Yücel, Tuğçenur; Kamiloğlu, Aybike; Kutlu, Naciye
In this study, the ultrasonic-assisted method was applied to extract phenolic, flavonoid, and antioxidant compounds from germinated mung beans. In addition, deep eutectic solvents (DESs) were chosen as solvents to support the green concept and to increase their applicability. Choline chloride is a quaternary ammonium salt and was used as the hydrogen bond acceptor (HBA), and compounds from the alcohol, organic acid, sugar, and amide groups were combined as hydrogen bond donors (HBD) to obtain 8 different DESs. Higher yields were obtained with ultrasonic-assisted DESs compared to the traditional method (maceration) when total phenolic compound and antioxidant activities were evaluated. While the most effective solvent for total phenolic compound yield was choline chloride:fructose, the highest antioxidant activity values were obtained with solvents using organic acids as HBD. Moreover, Blue Applicability Grade Index (BAGI) was used to assess the greenness of the applied ultrasonic-assisted spectrophotometric extraction and DESs. As a result, using green technology and green solvents was influential in the extraction of bioactive compounds, and their applicability was especially effective for mung beans.
AtıfScopus8WoS7OpenAlex8İncele - MakaleYalnız künye2025Scopus SJRQ1Optimization of surface modification parameters of fly ash with high calcium oxide (CaO) content to use as a filling material
Uçurum, Metin; Özdemir, Akın; Teke, Çağatay
Fly ash (FA) is the fine-grained waste product obtained by burning coal after being ground to specific sizes in thermal power plants, carried with flue gases, and kept in cyclones or electro-filters. Like every industrial waste, the possibilities of utilizing FA have been investigated, and it can be utilized as an additive in cement and concrete. Despite this, industrial waste, which increases daily in the world, brings many problems, especially environmental problems. For this reason, alternative usage areas of the waste in question are constantly being investigated. In this paper, FA containing approximately 50 % CaO from Afşin-Elbistan, Turkiye was processed with stearic acid in a planetary mill to be used as a filling material in industrial products, and it has a grain size of 68.10 μm on a d50 basis, a specific surface area (SSA) of 176.40 m2/g and a contact angle of 13.89. An optimization and characterization study was conducted to make the hydrophilic surface structure hydrophobic by mechanochemical surface modification. Also, surface modification parameters, such as operational speed (rpm), ball filling ratio (%), FA filling ratio (%), pulp density, stearic acid dosage (% of FA), and modification time (min.) were optimized with the D-optimal experimental design. Based on the optimum surface modification parameters, a coated fly ash (CFA) product was obtained with an active ratio of 99.70 %, a contact angle of 95.06o, a medium size (d50) size of 10.60 μm, and an SSA of 926.90 m2/g.
AtıfScopus8WoS8OpenAlex9İncele - MakaleAçık Erişim2025Scopus SJRQ1Electrospinning Encapsulation of Chlorophylls Microwave-Extracted from Spinach Waste and Utilization as Coloring Agent in Yogurt
Isik, Beyza Sukran; Bayram, Sinan; Altay, Filiz
Natural colorants have become a developing market because of consumer preferences, and more cost-effective and stable production is necessary. In the present study, a natural green colorant was obtained via microwave-assisted extraction from spinach waste to produce affordable, environmentally-friendly, and innovative colorants. The extracts were encapsulated with zein via uniaxial and coaxial electrospinning techniques to overcome the stability issues associated with their natural green color. The encapsulation efficiencies of uniaxially encapsulated chlorophyll extracted from spinach waste by microwave were 63.50 and 57.18 for chlorophyll a and b, respectively. The efficiencies of chlorophyll a and b by coaxial electrospinning were found 49.53% and 88.58%, respectively. The microwave-assisted extraction and the addition of eumelanin may contribute positively to the antioxidant activity and thermal stability of electrospun samples. The stability test against light revealed that 61% of chlorophyll a could be preserved by uniaxial electrospinning. In addition, when chlorophyll-loaded nanofibers were incorporated into yogurt, a more stable green color was achieved during storage.
AtıfScopus10WoS9OpenAlex11İncele - MakaleAçık Erişim2025Scopus SJRQ3Effects of Formaldehyde Scavenger on Mechanical, Physical, and Emission Test Results in Multi-Layer Pressed Chipboard Production
Çamlibel, Osman; Peker, Hüseyin; Ayata, Ümit; Ulay, Göksel
This study investigates the effects of different formaldehyde scavenger (FS) ratios on the physical, mechanical, and chemical properties of fiberboard composites. Experimental analyses included measurements of thickness, density, modulus of rupture (MOR), modulus of elasticity (MOE), internal bond strength (IB), shear strength (SS), moisture content, thickness swelling (TS), water absorption (WA), and formaldehyde emission (FE) levels. The results indicate that an increase in the FS ratio leads to a significant decline in mechanical properties. Specifically, MOR, MOE, and IB values decreased by 17.97%, 15.65%, and 16.33%, respectively. Changes in TS and WA were also observed, with TS increasing by up to 22.68% and WA decreasing by as much as 16.90%. In terms of formaldehyde emissions, a significant reduction was observed as the FS ratio increased. At a 15% FS ratio, formaldehyde emissions decreased by 43.24%, which is considered a positive outcome in terms of environmental and health impacts. Overall, the use of FS in specific ratios reduces FE while causing certain reductions in mechanical properties. These findings highlight the importance of optimizing FS usage for the production of low-FE fiberboards.
AtıfScopus3WoS2OpenAlex1İncele - MakaleAçık Erişim2025Scopus SJRQ1Experimental performance assessment of two-stage thermoelectric system in a closed-cycle drying process
Osta, Muhammet Harun; Yakut, Kenan; Köksal, Hüseyin
Traditional drying systems suffer from several limitations, including high energy consumption, insufficient hygienic control, and the inability to maintain precise temperature regulation. Although alternative drying systems have been developed to address these issues, they often encounter practical challenges due to their complex structures and the need for numerous external components. To overcome these limitations, this study proposes and experimentally evaluates a novel, independently operating, two-stage thermoelectric module (TEM) system integrated into a closed-loop drying setup that eliminates the need for external heating and dehumidification components. The proposed system addresses the efficiency and hygiene problems observed in conventional dryers by simultaneously performing air heating, cooling, and dehumidification functions through compact thermoelectric devices. The drying process consists of two stages: the first involves air pre-conditioning (heating/cooling), while the second is dedicated to dehumidification. The performance of the system has been evaluated based on key metrics such as cooling and heating capacities, the coefficients of performance (COP) for both stages, moisture removal rate (MRR), and moisture removal rate effectiveness (EffMRR). Experimental studies were conducted under input voltages ranging from 3 to 7 V, relative humidity levels between 60 % and 90 %, and varying airflow rates. Under 90 % relative humidity conditions and a 7 V input voltage, the system achieved a maximum moisture removal rate of 13.1 g/h. The first-stage TEM reached a heating capacity of 68.81 W and a cooling capacity of 26.34 W, while the second stage provided 21.17 W of cooling capacity.
AtıfScopus5WoS5OpenAlex5İncele - MakaleAçık Erişim2025Scopus SJRQ3A Social Approach to Environmental Sustainability: The Nexus Well-Being, Tourism, Digitalization and Renewable Energy in Scandinavian Countries
Isik, Cem; Ongan, Serdar; Aydin, Buket; Aydin, Rahman; Imamoglu, Ilyas Kays
This research explores the impact of subjective well-being (SWB) on CO2 emissions in Scandinavian countries based on the need to analyze the effects of social indicators shaping environmental sustainability. The study aims to introduce the Welfare-Based SWB approach to the literature by expanding the classical Environmental Kuznets Curve (EKC) hypothesis with the social welfare dimension. SWB is considered in this study to be a social reflection and indirect measure of economic growth, which is the core determinant in the classical EKC hypothesis. The second-generation cointegration test, the Durbin-Hausman, and AMG long-term forecasting methods were used in this context. According to the empirical findings, SWB and digitalization increase carbon emissions, while tourism revenues and renewable energy consumption reduce emissions. The findings indicate that the classical EKC hypothesis is not confirmed and, similarly, an increase in social welfare (SWB) does not automatically lead to environmental improvement. Therefore, policymakers should develop social policies that will increase environmental sensitivity along with an increase in welfare.
AtıfScopus16WoS13OpenAlex16İncele - MakaleAçık Erişim2024Green Supplier Assessment with Fuzzy Expert System Approach
Teke, Çağatay
Today, reasons such as increasing pollution on a global extent and limited raw material resources are increasing the interest in green supply chain management (GSCM). GSCM includes the processes starting from the very beginning of the production process of a product, completing the production, delivering the product to the customer, and recycling the product at the end of its useful life. Its main purpose is to eliminate or minimize the damages caused to the environment in all of these processes. In order to achieve this goal, it has great importance to assess the suppliers, which are one of the most important components of the production process, in terms of becoming a green supplier. In this study, a fuzzy expert system model has been developed to assess the green suppliers based on green production technology, environmental management system, pollution control, product cost, quality, and lead time criteria. Mean Square Error (MSE) and coefficient of determination (R2) have been calculated to measure the performance of the developed model. These calculated values show that the green supplier assessment performance of the developed model is quite high.
AtıfOpenAlex1TR Dizin1İncele - MakaleAçık Erişim2024Atık bitkisel yağlarla muamele edilmiş İroko (Milicia excelsa Welw. C.C. Berg) odununda beyazlık indeksi, renk ve parlaklık değerlerinin belirlenmesi
Ayata, Ümit; Camlibel, Osman
Günümüzde ahşap malzemenin sahip olduğu rengi değiştirmenin birçok farklı metotları (ısıl işlem, emprenye, ağartma, vb.) bulunmaktadır. Bu işlemler esnasında çevre dostu ürünlerin kullanılması gerek insan sağlığı gerekse ahşap endüstrileri için önem teşkil etmektedir. Bu çalışmada, atık bitkisel yağların (zeytinyağı, mısır yağı ve ceviz yağı) İroko (Milicia excelsa Welw. C.C. Berg) odunun yüzeylerine bir fırça ile uygulanması sonrasında meydana gelen bazı yüzey özellikleri araştırılmıştır. Uygulama öncesi ve sonrasında ahşap yüzeylerde beyazlık indeksi (WI*) [liflere dik (⊥) ve paralel (║)] değerleri, renk parametreleri (∆L*, ∆a*, ∆b*, ∆C*, ∆H*, ∆E*, a*, C*, L*, b* ve ho) ve parlaklık değerleri [20o, 60o ve 85o’lerde liflere dik (⊥) ve paralel (║)] belirlenmiştir. Bütün atık bitkisel yağ türleri uygulanmış deney örneklerinde a* ve C* değerleri artış gösterirken, L*, b* ve ho değerlerinde azalışlar elde edilmiştir. En düşük ∆E* değeri atık mısır yağında (23.70) bulunurken, en yüksek değer atık zeytinyağında (24.48) tespit edilmiştir. Her iki yöne ait olan WI* değerlerinde atık yağların uygulandığı örneklere ait sonuçlar kontrol örneklerininkine nazaran daha düşük olarak tespit edilmiştir. Uygulanan atık yağlar ile WI* değerlerinde azalış belirlenmiştir. Bütün atık yağ türlerinde liflere dik ve paralel yönlerde parlaklık değerleri 20o ve 60o’lerde azalırken, 85o’de artmıştır. Kullanılan tüm atık yağların iroko odunu yüzeylerinde yüzey özelliklerini değiştirici etkide bulunduğu görülmüştür.
