Çorlu Mühendislik Fakültesi Koleksiyonu

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https://hdl.handle.net/20.500.11776/4022

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MUZ KABUĞU EKSTRAKTININ PAMUK VE PAMUK-POLİESTER KARIŞIMLI KUMAŞLARDA GÜÇ TUTUŞURLUĞA ETKİSİNİN İNCELENMESİ
(2021) Balaban, Fehmi Çağlar; Koruyucu, Aslıhan
Pamuk ve poliester günümüzde en çok kullanılan konvansiyonel lifler olarak tekstil endüstrisinde önemli bir paya sahiptir. Bu liflerin güç tutuşurluk terbiye işlemlerinde kullanılan kimyasallara alternatif olarak çevre atık yükü düşük ve sürdürülebilir doğal malzemelerin elde edilmesi çalışmanın çıkış noktasını oluşturmaktadır. Bitkisel atık ekstratları ilk olarak; yakma, haşıl sökme, merserize ve bazik ön terbiye işlemleri ile aynı gramaj ve konstrüksiyona sahip %100 pamuklu kumaşlara emdirme ve kaplama yöntemlerine göre uygulanmıştır. İkinci olarak ise; yakma, soğuk bazik ön terbiye işlemlerinden geçirilen %50 pamuk-%50 poliester karışımlı dokuma kumaşlar üzerine aynı yöntemlerle uygulanmıştır. Muz kabuğu atık ekstraktlarının pamuk ve pamuk-poliester karışımlı kumaşların yapısındaki dağılımını incelemek için taramalı elektron mikroskobu (SEM) görüntüleri, sıcaklık-zaman fonksiyonuna bağlı kütle kayıpları termogravimetrik analizleri (TGA) ve limit oksijen indeksi (LOI) analizi gerçekleştirilmiştir. Sonuç olarak; muz kabuğundan elde edilen ekstraktlarla yapılan emdirme ve kaplama işlemlerinin pamuklu ve pamuk-poliester karışımlı kumaşların termal dayanım özelliklerinde iyileşme sağladığı, kumaşların alev alması için ortamda bulunması gereken oksijen miktarında olumlu yönde artış sağladığı, kumaş morfolojisinde olumsuz herhangi bir etkiye sebep olmadığı tespit edilmiştir. Yapılabilecek metot iyileştirmeleriyle birlikte; bu özelliklerde gelişme sağlanabileceği öngörülmektedir.
Numerical and Economic Analysis of Hydronic-Heated Anti-Icing Solutions on Underground Park Driveways
(Mdpi, 2023) Kayacı, Nurullah; Kanbur, Barış Burak
Snow and ice forming on the entrance and exit driveways of underground car parks of buildings brings serious difficulties and risks in safe parking for vehicles in winter. Even though traditional methods such as chemical salt and snow plowing reduce slippery conditions on driveways, they also result in infrastructure- and environment-related damages. Hydronic heating is an alternative way to prevent snow and ice forming; thereby, the hydronic heating driveway (HHD) is a promising technique for energy-efficient and environment-friendly solutions. This study presents a time-dependent three-dimensional numerical heat transfer model for HHD applications with realistic boundary conditions and meteorological data in the MATLAB environment. After developing the numerical heat transfer model, the model is applied to a case study in Istanbul, Turkey and followed by an economic comparison with the commercial electrically-heated driveways (EHD) method that is applied in two different ways; applying the electric cables in (i) whole driveway and (ii) only tire tracks. Different escalation rates in natural gas and electricity, hot fluid inlet temperature, air temperature, and the number of parallel pipes are the main parameters in the case study. Results show that the decrease in pipe spacing drops the investment cost term but it needs a higher supplied fluid temperature for anti-icing, and therefore the operating cost term increases. Among other cases was the number of parallel pipes, with 50 being the most economically feasible solution for all air temperatures ranging from 0 degrees C to -10 degrees C. The economic comparison shows that the EHD with only tire tracks has the minimum total cost as it significantly decreased both the operating and investment cost terms. In case of an anti-icing requirement on the whole road surface, the HHD system was found to be preferable to the EHD whole driveway scenario at air temperatures of 0 degrees C and -5 degrees C, while it is more beneficial only for the high electricity escalation rates at the ambient temperature of -10 degrees C.
An Overview of the Past, Present and Future of Merinoization Activities in Sheep Breeds with Quality Wool Yield in Turkey and Previous Studies on the Wool Characteristics of the Turkish Merino (Karacabey Merino) Breed
(Chamber of Textile Engineers, 2022) Atav, Rıza; Buğdaycı, Berhan
The most important factor determining the quality of fleece to be obtained from a sheep is genetic capacity. From this point of view, it can be said that our domestic sheep breeds are meat or dairy sheep breeds. It can be said that the breed with the highest potential to obtain quality fleece in Turkey is Karacabey merino (Turkish merino). The two most critical parameters that determine the quality of a fleece are fineness and length. In order for a fleece to be usable in the worsted weaving industry, its fineness must be 24.94 microns and below, and its length must be longer than 8 cm. However, studies have shown that the percentage of Karacabey merino sheep with wool with a fineness value of less than 24 microns is very low. For this reason, it is thought that sheep breeds with high quality wool yield can be developed in our country with multidisciplinary projects to be carried out especially by textile engineering, zootechnology department of agricultural engineering, and veterinary faculties. In this review article, information is given about the history of merinoization in Turkey, our native merino breeds and previous studies on the fleece characteristics of the Karacabey merino breed. © 2022,Tekstil ve Muhendis. All Rights Reserved.
Distinguishing yak and cashmere fibers from each other to prohibit mislabeling through microscopic and spectroscopic analysis
(Taylor and Francis Ltd., 2023) Atav, Rıza; Ergünay, Uğur; Gürkan Ünal, Pelin
Since yak and cashmere fibers show very similar properties and yak fibers are considerably cheaper than cashmere, it is an important issue that yak is used instead of cashmere in the industry and the final product is sold as cashmere with misleading labelling. Therefore, researchers have been working on developing a method for differentiating these two fibers for many years. In the studies carried out in literature to date, no definitive method has been found which can distinguish these fibers from each other. Accurate results can only be obtained with DNA analysis, and this method is difficult and expensive to apply. On the other hand, when the literature was examined, it was seen that various fiber properties were investigated to distinguish yak and cashmere fibers. However, fibers having the same color were not systematically used together in these studies. In this study, both white and brown fibers from cashmere and yak origin were examined and thus, whether any method would be useful or not to distinguish yak and cashmere fibers in general or white cashmere from white yak and brown cashmere from brown yak in particular was presented. Within the scope of present work, it was aimed to find a way of distinguishing these fibers from each other by making various microscopic and spectroscopic analysis. For this aim fiber cross-section and longitudinal appearance analysis by light microscopy; scale morphology (scale structure, scale shape, scale pattern), scale height (thickness), scale length and scale frequency analysis by scanning electron microscopy; color (CIE L*a*b* color coordinates) analysis with spectrophotometer, fiber functional group analysis by Fourier transform infrared spectroscopy and fiber combustion behavior analysis with thermogravimetric analysis were conducted. © 2023 The Textile Institute.
Wave Propagation in Shear Beams Comprising Finite Periodic Lumped Masses and Resting on Elastic Foundation
(Mdpi, 2023) Özmutlu, Aydın
In this study, the dispersion of an infinite shear beam with a lumped mass connected at periodic distances and resting on an elastic foundation was examined. The effect of periodicity in the finite region of the lumped masses on wave propagation was investigated through a one-dimensional model. The dispersion relationship for Bragg scattering, which consists of one-dimensional periodic lumped masses, was derived using the transfer matrix method. Subsequently, to evaluate the effect of parameters such as the magnitude of the lumped mass and foundation stiffness on the dynamic response of the shear beam, several simulations were performed. The band frequency characteristics of the shear beam are demonstrated with respect to the variations in stiffness and mass. Using the wave-based approach, the effect of periodic masses on wave propagation in a finite region of an infinite beam was revealed. Periodic masses have been shown to have a positive effect on the displacement amplitude; in other words, a lumped mass barrier is effective in providing wave attenuation.
Effects of Sintering Temperature on Microstructural Properties of Ni1-xZnxFe2O4 Synthesized by Powder Metallurgy
(Kaunas Univ Tech, 2022) Aras, Mustafa; Şahin, Mümin; Gündoğdu, Özcan
Powder metallurgy (PM) is a modern manufacturing method that allows high-tech materials, alloys and complex shaped parts to be manufactured with precision and almost without the need for finishing operations such as deburring. PM involves powder production, powder processing, forming operations, pressing and sintering or pressure-assisted hot consolidation. This paper reports results on Ni1-xZnxFe2O4 produced by powder metallurgy at different sintering temperatures. Ni1-xZnxFe2O4 is an interesting functional magnetic material due to its special properties such as stability, very good dielectric properties, electrical resistivity, low dielectric loss, chemical stability, etc. all being important in cutting-edge technology. The use of Ni1-xZnxFe2O4 in diverse fields such as the biomedical field i.e. drug delivery is another vibrant research area. SEM imaging was performed for the structural analysis of the produced bulk sample. EDXRF analyses were performed for elemental composition along with SEM images.
Prediction of heat transfer characteristics in a microchannel with vortex generators by machine learning
(Walter De Gruyter Gmbh, 2023) Gönül, Alişan; Çolak, Andaç Batur; Kayacı, Nurullah; Okbaz, Abdülkerim; Dalkılıç, Ahmet Selim
Because of the prompt improvements in Micro-Electro-Mechanical Systems, thermal management necessities have altered paying attention to the compactness and high energy consumption of actual electronic devices in industry. In this study, 625 data sets obtained numerically according to the change of five different geometric parameters and Reynolds numbers for delta winglet type vortex generator pairs placed in a microchannel were utilized. Four dissimilar artificial neural network models were established to predict the heat transfer characteristics in a microchannel with innovatively oriented vortex generators in the literature. Friction factor, Nusselt number, and performance evaluation criteria were considered to explore the heat transfer characteristics. Different neuron numbers were determined in the hidden layer of each of the models in which the Levethenberg-Marquardt training algorithm was benefited as the training algorithm. The predicted values were checked against the target data and empirical correlations. The coefficient of determination values calculated for each machine learning model were found to be above 0.99. According to obtained results, the designed artificial neural networks can provide high prediction performance for each data set and have higher prediction accuracy compared to empirical correlations. All data predicted by machine learning models were collected within the range of +/- 3% deviation bands, whereas the majority of the estimated data by empirical correlations dispersed within & PLUSMN;20% ones. For that reason, a full evaluation of the estimation performance of artificial neural networks versus empirical correlations data is enabled to fill a gap in the literature as one of the uncommon works.
Improvement of metallurgical properties of A356 aluminium alloy by AlCrFeSrTiBSi master alloy
(Walter de Gruyter GmbH, 2023) Teker, T.; Yılmaz, Serdar Osman; Karakoca, Alper
A new AlCrFeSrTiBSi master alloy was manufactured by in situ synthesis in Al melt, and compared with AlBSr master alloy. Microstructures of A356 alloy modified with AlCrFeSrTiBSi master alloy were investigated, and the structural details of the new cast A356 alloy were evaluated by X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), microhardness and differential thermal analysis (DTA). AlBSr master alloy typically formed ?-Al and granular SrB6 phases in A356, and the samples inoculated with AlCrFeSrTiBSi master alloy consisted of additionally AlCrFeSi phase with irregular blocks. The addition of 0.1 wt%AlCrFeSrTiBSi alloy to the A356 alloy significantly refined and modified the grain structure together. The structure of eutectic Si converted from acicular form to fibrous. The size of ?-Al dendrites declined from ?1000 ?m to ?100 ?m. The strength values of the A356 alloy were developed by ?70% with the addition of 0.1 wt%AlCrFeSrTiBSi master alloy. © 2022 Walter de Gruyter GmbH, Berlin/Boston.
Joint performance of medium carbon steel-austenitic stainless steel double-sided TIG welds
(Walter de Gruyter GmbH, 2023) Teker, T.; Aydın, S.; Yılmaz, Serdar Osman
AISI 1040 and AISI 304 steel plates of 10 mm were joined without pretreatment by double-sided TIG arc welding (DSAW). Joints were manufactured by using welding currents of 420, 440, and 460 A. The microstructural variations in the interface of the weld samples were defined by optical microscopy, scanning electron microscopy, energy dispersive spectroscopy and microhardness analysis. V-notch impact and tensile tests were done to detect the weld strength of the weld samples. In DSAW welding of different steels, a full penetration joint was achieved without opening the weld edge. The current intensity had a major effect on the symmetrical and hourglass shape in welds. Welding at 460 (A) showed acceptable joint quality. Tensile and impact energy quantities of welded joints had significant ratios. Fractures in the weld metal of the samples were ductile mode. © 2022 Walter de Gruyter GmbH, Berlin/Boston.
Three-Dimensional Thermal Vibration of CFFF Functionally Graded Carbon Nanotube-Reinforced Composite Plates
(Springer, 2023) Uymaz, Bahar; Uymaz, Gökay
Purpose: Three-dimensional thermal vibration analysis of functionally graded carbon nanotube (FG-CNT) reinforcement composite plates is performed for uniform, linear and sinusoidally temperature distribution. Methods: The reinforcement directions is considered through the thickness according to four reinforcement models as UD, FG-V, FG-O and FG-X are examined. As the components of the composite, the material properties of both the CNT forming the reinforcement phase and the polymer forming the matrix phase change depending on the temperature, and this is the focus of this study. The effective material properties of the FG-CNT reinforced composite are determined by the mixtures rule. The three displacements of the plates are expanded by a series of Chebyshev polynomials multiplied by appropriate functions to satisfy the essential boundary conditions. The natural frequencies are obtained by the Ritz method. Results: It is shown that the numerical results of the current approach are compared with the results of other researchers for validation, the results appear to be in good agreement. The effects of the thickness-to-length ratio and different volume fraction distributions for cantilever (CFFF) boundary conditions in considered thermal environments are investigated. The effect of different boundary conditions such as clamped (CCCC), simply supported (SSSS), simply supported through the x-axis and clamped through the y-axis (SCSC) and simply supported through the x-axis and free through the y-axis (SFSF) is also examined. It is shown that the increase in the amount of temperature and the type of temperature distribution are effective on the decrease of frequencies. © 2023, Krishtel eMaging Solutions Private Limited.
Development and experimental validation of finite element models for a prestressed lead extrusion damper
(Elsevier Ltd, 2023) Çalım, F.; Güllü, A.; Soydan, Cihan; Yüksel, E.
The emerging trend in earthquake-resistant structural design is to dissipate some part of the seismic input energy through energy-dissipating devices (EDDs). A prominent candidate to serve this purpose is the lead extrusion damper (LED), which dissipates seismic energy by the extrusion of lead through the displacement of a bulged shaft. The LEDs should be designed as they meet the demands of the host structural system. Hence, predicting the force–displacement relation and energy dissipation characteristics of the LED is essential. To serve this purpose, comprehensive three-dimensional finite element models (FEMs) were developed in this study to simulate the cyclic behavior of a prestressed LED. The methodology consisted of performing coupon tests, the development of FEMs, and experimental verification. Coupon tests were performed for lead and steel to simulate the nonlinear material behaviors better. The models were validated against the experimental results of the LED and a steel beam-to-column connection. In general, the adapted model satisfactorily captured the experimental results. The maximum differences in the maximum force and dissipated energy predictions were about 7.5% for the generated FEMs. In addition, the mean relative difference in predicting damper forces for eight LEDs selected from the literature was about 6%. The low relative differences between the models and experiments demonstrated that the adapted FEM could reliably estimate the cyclic response of the LEDs. It can be stated that the adapted three-dimensional finite element modeling strategy can be utilized robustly for design purposes. © 2023 Institution of Structural Engineers
MECHANICAL PROPERTIES OF MORTARS CONTAINING WOOD BOTTOM ASH INSTEAD OF CEMENT
(2022) Cihan, Mehmet Timur; Avşar, Yunus Emre
Carbon dioxide (CO2) released into the atmosphere during the production of Portland cement (PC) is one of the important factors causing global warming. Therefore, studies are carried out on different materials to reduce PC consumption. The effect levels of the wood bottom ash (WBA) ratio and specimen age on the response variables (compressive strength, flexural strength, and ultrasonic pulse velocity) were investigated in this study. Mortar specimens were produced using PC, WBA, CEN standard sand, and distilled water. The produced specimens were cured in water until the test day. WBA ratios are 0%, 5%, 10%, 20%, 35% and 50% by weight of binder. As a result, it was determined that the optimum WBA ratio was 5%. In addition, R2 values of response variables were found to be high (ultrasonic pulsed wave velocity; 0.8925, flexural strength; 0.9356, compressive strength; 0.9404) by analysis of variance (ANOVA). This shows that the models have a high correlation. Moreover, the terms added to the models have a significant effect on the responses.
A Numerical Investigation of Induced and Embedded Trench Installations for Large-Diameter Thermoplastic Pipes under High Fill Stresses
(Mdpi, 2023) Kılıç, Havvanur; Biçer, Perihan; Bozkurt, Sercan
The induced trench installation method is applied by placing material with high compressibility on rigid pipes to reduce the earth pressures acting on them. Although the performance of this method for rigid pipes has been investigated, research on thermoplastic pipes is very limited. In this study, induced trench installation (ITI) and embedded trench installation (ETI) of large-diameter thermoplastic pipes subjected to high fill stresses were investigated by numerical analysis. The numerical model has been verified by considering the field experiments, and a series of analyses were carried out by placing Expanded Polystyrene Foam (EPS Geofoam) in ITI and ETI models. Pipe stresses and deflections were evaluated by considering the pipe diameter, stiffness, and backfill properties. The ITI and ETI models in thermoplastic pipes reduced the stresses acting on the pipes and increased the positive arching regardless of the deflection of the pipe. For pipes with an inner diameter of 0.762 to 1.524 m under 30 m of fill stress, approximately 1.5 to 3.0% deflection occurred. In the ETI model, the horizontal earth pressure in the spring line of the pipe decreased from 65 to 40% depending on the backfill type, and an approximately uniform stress distribution was formed around the pipe.
DEVELOPMENT OF FLEXIBLE SENSOR STRUCTURES WITH ALERT FEATURE ON ROLLER BLIND SURFACE WORKING WITH SOLAR ENERGY
(Chamber of Textile Engineers, 2022) Hacıoğlu, B.; Yıldırım, M.; Alisoy, Hafız
In the project, roller blinds with alarm sensors working with solar energy were developed. It is aimed to develop the alarm system, which is a security system product that has become the need of every house, on the curtain surface by designing flexible sensor structures. Lightweight fabric design, sensor design, system design and mobile application studies were carried out. User tests of the product with optimum values were carried out. As a result of the evaluations, it was seen that the lightweight fabric rate was 34% and the capacitive sensing distance of the selected pattern was 15 cm. © 2022, Tekstil ve Muhendis. All Rights Reserved.
Tam batmış bitki tarlasının açık kanal akım hızlarına etkisinin flow-3d ile modellenmesi
(2022) Yılmazer, Didem; Ozan, Ayşe Yuksel; Ayna, Gökhan; Cihan, Kubilay
Bu çalışmada, deneysel olarak yapılan tam batmış bitkilerin açık kanal akımlarına olan etkisinin incelendiği bir çalışma, FLOW-3D ile modellenmiştir. Deney sonuçları ve sayısal model sonuçları karşılaştırılmıştır. Modellemede Yılmazer ve ark. [10] tarafından gerçekleştirilen deneye ait veriler kullanılmıştır.
TÜRKİYE’NİN ENERJİ VERİMLİLİĞİ VE İKLİM DEĞİŞİKLİĞİ PERFORMANSI: MEVCUT DURUM VEGELECEK PROJEKSİYONU
(2020) Duman Altan, Aylin; Sağbaş, Aysun
Son yıllarda ülkemizde hızla artan teknolojik gelişmelerin yanı sıra, artan nüfus ve refah düzeyi gibi faktörler nedeniyle, enerji tüketim miktarı ve bu eksende Türkiye’nin dışa bağımlılığı giderek artmaktadır. Bu durum, ülke ekonomisi ve çevresel sürdürülebilirlik açısından üzerinde durulması gereken temel unsur olarak karşımıza çıkmaktadır. Türkiye’de enerji ekonomisi bakımından çeşitli arz-talep politikaları geliştirilmiş olsa da, dışa bağımlılığının önüne geçilememiştir. Türkiye gibi hem enerji tedarikinde dışa bağımlı olan, hem de enerji kayıplarının fazla olduğu ülkelerde yapılması gereken ilk uygulama, tüm alanlarda ve süreçlerde enerji tasarrufu miktarlarının belirlenmesi ve ilgili çalışmaların devlet politikaları kapsamında desteklenerek enerji verimliliğinin arttırılmasına yönelik yatırımların hayata geçirilmesidir. Enerji verimliliği uygulamalarının sağlıklı olarak hayata geçirilemediği alanlarda, fazla tüketimi karşılayacak yeni enerji arz sistemleri; hem ülke ekonomisi açısından yüksek maliyet oluşturacak hem de enerji kayıpları devam edecektir. Bu nedenle sınırlı olan doğal kaynaklarımız da dikkate alınarak, her alanda enerjinin etkin kullanımına yönelik strateji ve politikalar belirlenmeli ve uygulamalar devreye alınmalıdır.Bu çalışma kapsamında, Türkiye’nin enerji verimliliği ve iklim değişikliği performansı konusunda mevcut durumu ve gelecek projeksiyonları irdelenmiş olup, enerji tüketiminde önemli sektörler bazında değerlendirmeler yapılmıştır. Dünyada ve Türkiye’de enerji yoğunluğu, enerji tasarruf yatırımları ve tasarruf değerleri karşılaştırmalı olarak verilmiştir. Özellikle sanayide enerji verimliliği konusunda yapılan çalışmalar değerlendirilmiş olup, Türkiye’de enerji verimliliği uygulamalarının arttırılması için öneriler sunulmuştur.
BEST WORST METODU İLE İNŞAAT SEKTÖRÜNDE RİSK DEĞERLENDİRMESİNE YENİ BİR YAKLAŞIM
(2021) Güneri, Ali Fuat; Karakurt, Necip Fazıl; Hekimoğlu, İhsan
İnşaat sektörü, Türkiye’de iş kazalarının ölüm veya ciddi yaralanmalarla sonuçlandığı bir sektördür. Bu nedenle üzerine yoğunlaşılması ve hızlı bir şekilde tedbir alınması gereken İş Sağlığı ve Güvenliği (İSG) risk faktörleri oldukça fazla sayıdadır. Makalede daha önce İSG literatüründe kullanılmamış yeni bir yaklaşım ile İnşaat sektörü İSG risk faktörleri önceliklendirilmiştir. İnşaat sektörü literatüründe yer alan farklı kaynaklar incelenerek elde edilmiş 15 farklı risk faktörünün önceliklendirme çalışması yapılmıştır. Bu önceliklendirme yapılırken, yeni yaygınlaşmakta olan Çok Kriterli Karar Verme yöntemlerinden Best Worst Metot kullanılmıştır. İnternet üzerinden yapılan anket yoluyla uzman görüşleri toplanmış, bu görüşler neticesinde risk faktörlerinin birbirleri açısından önem derecelerini gösteren ikili karşılaştırma vektörleri belirlenmiştir. Bu ikili karşılaştırma vektörlerinin makalede verilen doğrusal programlama modelinde çözülmesi neticesinde, faktör ağırlıkları elde edilmiştir. Toplam 51 katılımcının bulunduğu anket çalışmasında 37 adet anket tutarsız bulunması nedeniyle çalışmanın kapsamından çıkartılmıştır. Tutarlı anket sonuçları farklı ortalama alma yöntemleri ile incelenmiştir. Elde edilen sonuçlara göre yüksekten düşme, yüksekten malzeme düşmesi, ağır kaldırma ve toza maruz kalma faktörleri en önemli risk faktörleri olarak belirlenmiştir.
Classifying environmental significance levels of production-oriented operational activities with F-ARAS and F-MOORA methods
(Wiley, 2022) Polat, Ulviye
In most decision analysis approaches, application results are obtained in the form of a ranking or selection set. However, classification is needed for analysis of results. In this study, environmental significance levels and range values were created for the ranking results obtained using fuzzy Multi Criteria Decision Making approaches. Environmental significance levels have been established for 26 operational activities for which environmental impacts have been determined. Operational activities were analyzed using the Fuzzy-Additive Ratio Assessment (F-ARAS), Fuzzy-Multi Objective Optimization by Ratio Analysis (F-MOORA) Ratio, and F-MOORA Reference Point methods with six evaluation criteria, including the total impact score criteria. The results obtained were analyzed with environmental significance levels and range values, which can also be named as environmental risk classes created for the first time in this study depending on the changes in standard deviation. According to the comparison results, when F-ARAS and F-MOORA Ratio methods were evaluated together, 19 activities were in the same class (73%). Integr Environ Assess Manag 2022;00:1-12. (c) 2022 SETAC
Magnetic Iron-Doped Filtered Coffee Bio-Waste Based Carbon for the Adsorption of Reactive Blue 21
(Pleiades Publishing Inc, 2022) Çifci, Deniz İzlen; Aydın, Neşli
Intensive coffee consumption causes a high amount of coffee waste to be produced annually. In this study, the adsorption of Reactive Blue 21 (RB21) dye by using the magnetic iron-doped filtered coffee bio-waste (magnetic-FCW) was investigated in detail. Magnetic-FCW was characterised by SEM-EDX, mapping, FTIR, and Raman analysis and it was found that the material contains 3.4% Fe by weight. The highest RB21 removal was observed as 97.8% at pH 3 and 5 g/L magnetic-FCW concentration. It was determined that the adsorption of RB21 dye by magnetic-FCW was more describable by the pseudo second-order kinetic model, and k(2) was calculated as 0.086 and 0.0016 g/mg min at 50 and 100 mg/L RB21 concentrations, respectively. In addition, RB21 dye removal with magnetic-FCW was more amenable to the Langmuir isotherm model and the q(max) was calculated as 15.80 mg/g. In conclusion, the use of this bio-waste, which is formed as a result of the rapid increase in the consumption of filtered coffee, in the removal of dyes such as RB21 dye from wastewater, makes it possible to include magnetic-FCW in the field of waste management as a low-cost adsorbent material, which reduces operating costs and makes it possible to reuse these wastes in the waste sector. Collecting these bio-wastes, especially from cafes and restaurants and, reusing them could serve the circular economy as well.
Effect of Supplementary Cementitious Materials with Similar Specific Surface Area on Cementitious Composite Systems
(Amer Soc Testing Materials, 2023) Sevim, Özer; Şengül, Çağrı Göktuğ; Kartal, Saruhan; Toklu, Kenan; Çağlar, Yasin
This study investigated the effect of the mechanical and durability properties of cementitious composite systems with supplementary cementitious materials (SCMs), including fly ash (FA), ground granulated blast furnace slag (GGBS), and bottom ash (BA), with similar specific surface areas (similar to 3,300 cm2/g). FA, GGBS, and BA were ground to a specific surface area of similar to 3,300 cm2/g (about the cement-specific surface area) and then replaced with cement at 5 %, 10 %, 15 %, and 20 % replacement ratios. The compressive strength, flexural strength, length change, and rapid chloride ion permeability of the cementitious composites incorporating FA, GGBS, and BA with similar specific surface areas were recorded after 7-, 28-, and 90-day curing periods. As a result, cementitious composites containing GGBS improved the mechanical and durability properties at the maximum rate. It was shown that the properties of cementitious composites containing 20 % GGBS yielded better results than the control specimens without any SCMs.

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