Yazarlar
- Tanyol, Mehtap(22)
- Yildirim, Numan(17)
- Karataş, Mehmet(14)
- Erguven, Gokhan Onder(13)
- Topal, Murat(13)
- Ince, Muharrem(12)
- Yildirim, Nuran Cikcikoglu(10)
- Kismet, Yilmaz(9)
- Öbek, Erdal(8)
- Arslan Topal, E. Işıl(7)
- Etli, Serkan(7)
- Goksu, Ali(7)
- Gul, Muhammet(7)
- Gülmez, Nihan(7)
- Ogedey, Aysenur(7)
- Uysal, Turan(7)
- Yonten, Vahap(7)
- Gürler, Nedim(6)
- Kaya, Sema Kayapinar(6)
- Sabanci, Serdal(6)
- Serdar, Osman(6)
- Yön, Merve Şahin(6)
- Alp, Hevidar(5)
- Aydoğmuş, Ercan(5)
- Benli, Ahmet(5)
- Cemalgil, Selim(5)
- Erdemoğlu, Murat(5)
- Erust, Ceren(5)
- Ince, Olcay Kaplan(5)
- Oguz, Ensar(5)
- Torğut, Gülben(5)
- Yilmaz, Mehmet(5)
- Yucesan, Melih(5)
- Celik, Erkan(4)
- Demir, Veysel(4)
- Dener, Murat(4)
- Doğan, Akar(4)
- Fırat, Tülay(4)
- Pekdemir, Mustafa Ersin(4)
- Tanaydin, Mehmet Kayra(4)
Yayınlar
- MakaleAçık Erişim2022Effects of single-walled carbon nanotubes and steel fiber on recycled ferrochrome filled electrical conductive mortars
Dehghanpour, Heydar; Doğan, Fatih; Subaşi, Serkan; Maraşli, Muhammed
The production of electrically conductive concrete was introduced years ago among construction materials, generally for anti-icing. The present study investigates the electrical, mechani-cal, dynamic, and microstructural properties of recycled ferrochrome filled cementitious mortars containing single-walled carbon nanotubes (SWCNTs) and steel fiber. Within the scope of the study, a total of 5 different mixtures were obtained. 7, 14, and 28-day non-destructive and 28-day compressive and bending tests of cementitious conductive mortars obtained from five different mixtures were performed. The two-point uniaxial method was used to determine the electrical conductivity properties of the samples. The damping ratio of the samples was obtained by performing dynamic resonance tests. Ultrasound pulse velocity (UPV) and Leeb hardness tests were performed as other non-destructive testing methods. Microstructure analysis at the interfaces of conductive concrete samples was characterized by scanning elec-tron microscopy (SEM), EDS (Energy-Dispersive X-ray Spectroscopy), and X-ray diffraction (XRD). The results showed a logical agreement when comparing their mechanical, physical, and dynamic properties. When SWCNT is used with steel fiber, the conductive mortar samples exhibited good conductivity, while their compressive and bending strengths turned below.
AtıfScopus11OpenAlex13
İncele - MakaleYalnız künye2022Scopus SJRQ2Corrosion potential and electromagnetic shielding effectiveness of geopolymer tiles produced with waste metal particles
Gülmez, Nihan; Koçkal, Niyazi Uğur; Özen, Şükrü; Ateş, Kayhan
This study is related to the production of special geopolymer specimens, where high effectiveness is provided in terms of electromagnetic interference (EMI) shielding and corrosion resistance. The study is important for the preparation of silica fume/slag based geopolymers by using waste steel and iron powder as a partial substitute for slag aggregate and thus to provide an effective solution to the disposal problems of waste metals. The electromagnetic interference shielding effectiveness (SE) of geopolymer tiles of 7.6 ± 0.1 mm thickness with different metal contents was measured at 4.9–7.05 GHz. Corrosion activity was monitored by measuring the half-cell potential of copper/copper sulphate (Cu/CuSO4) on specimens kept under controlled laboratory conditions for a period of 90 days at %60 relative humidity according to ASTM C876. In addition, anextensive evaluation of the optimization research on the design and proportion of mortar mixtures is presented here. EMI shielding effectiveness of slag based geopolymer tile with 10% steel particles has been determined as 26.1 dB in the frequency range 4.9–7.05 GHz. The results show that the shielding effectiveness reached a maximum of 23.1 decibels (dB) for geopolymer tiles in 40% iron powder content. Also, from experimental results, it was learned that geopolymer specimens with high slag content as binders in the mixtures showed better corrosion resistance.
AtıfScopus10WoS10OpenAlex10
İncele - MakaleAçık Erişim2022Scopus SJRQ1Preparation of ε-Caprolactone/Fe3O4 Magnetic Nanocomposite and Its Application to the Remazol Brilliant Violet 5R Dye Adsorption from Wastewaters by Using RSM
Pekdemir, Mustafa Ersin; Tanyol, Mehtap; Torğut, Gülben
In this study, poly (ε-caprolactone)/Fe3O4 magnetic nanocomposite (PCL/Fe3O4 MNC) was synthesized by ring-opening polymerization. Then, PCL/Fe3O4 MNC was used as a novel adsorbent to remove remazol brilliant violet 5R (RBV 5R) from the aqueous media. The effects of PCL/Fe3O4 MNC dosage, process time, and initial RBV 5R concentration on the removal of RBV 5R were studied using the central composite design (CCD) method. The adsorption process was optimized using the response surface methodology, and the optimum conditions were defined. Optimum RBV 5R removal of 95.40% was obtained at a contact time of 167.98 min, PCL/Fe3O4 MNC dosage of 0.40 g, and RBV 5R concentration of 7.18 mg L−1. The process was also designed using the adsorption kinetic models and isotherm. The experimental data of RBV 5R adsorption on PCL/Fe3O4 MNC followed the Langmuir isotherm and pseudo-second-order kinetic models than the other models. Morphological and chemical properties of the adsorbent-adsorbate system indicated the high adsorption yield of RBV 5R on PCL/Fe3O4 MNC was achieved. The structural characteristics of the PCL/Fe3O4 MNC were analyzed by Fourier-transform infrared, attenuated total-reflectance (ATR), and X-ray diffraction. ATR tests showed that no significant change in chemical bond is found in PCL/Fe3O4 MNC before and after the adsorption process. The morphology of composites was investigated by scanning electron microscopy. A vibrating sample magnetometer (VSM) was used for the measurement of the magnetic property. Thermal analysis of MNC was studied using thermogravimetric analysis and differential scanning calorimetry instruments.
AtıfScopus6WoS5OpenAlex6İncele - MakaleAçık Erişim2021Removal of Chemical Oxygen Demand, Total Organic Carbon and Color from Textile Industry Wastewater by Using Phanerochaete chrysosporium (ME446)
Erguven, Gokhan Onder; Yildirim, Numan; Çelik, Aytekin
Wastewater discharge from textile industries concern environmental risks. Superiority of microbial methods over other high cost combined methods includes conversion of persistent organic materials to non-toxic last materials, sustainability, low cost, and comfortable. Textile wastewaters can have opposite effects on the quality of water in total organic carbon (TOC) and Chemical oxygen demand (COD). Agitation cultures can reach the surface area of the dyes, whereas a static cannot do. Biotreatment of textile wastewater from the dyeing process using white-rot fungus Phanerochaete chrysosporium (P.C) was investigated in agitated and static culture conditions. Dye is the major pollutant component in this wastewater includes some different organic pollutants. The treatment mediums containing distilled water in 1:10 ratio of wastewater were compared for treatment efficiency of P.C. Especially in agitated conditions at 27 oC and 150 rpm, it was achieved a successful treatment results. Under these conditions, a 48h long treatment reduced by 91,46 % of the original COD (from 1484 mg l-1) and by 94,92% the TOC (initial was 723.66 mg l-1). Moreover, treatment reduced color by 86,28 % from 3.550 A540 to 0.487 A540 at the end of the study. The decolorization properties of P.C obtained high performance and we determined P.C showed up to effective removal rate for COD and TOC within 48 hours. We suggest that these fungus pellets of P.C can reach the decolorization and can be a useful tool for bioremediation of textile dye wastewater within a short time period.
AtıfOpenAlex3İncele - MakaleAçık Erişim2021Atık lastiklerden elde edilen siyah karbonun asfaltın işlenebilirlik özelliklerine etkisi
Geçkil, Tacettin; İnce, Ceren Beyza; Aksağan, Zülfükar
Bu çalışmada, atık lastiklerden elde edilmiş olan siyah karbon (SK) katkısının asfaltın orta ve yüksek sıcaklıklardaki işlenebilirlik özellikleri üzerindeki etkisi araştırılmıştır. Bu amaçla, penetrasyon sınıfı B 160/220 olan saf asfalta ağırlıkça %5, 10, 15 ve 20 oranlarında SK eklenerek modifiye asfaltlar elde edilmiştir. Saf ve modifiye asfaltların fiziksel özellikleri penetrasyon, yumuşama noktası ve düktilite testleri ile belirlenmiştir. Ayrıca, bağlayıcıların sıcaklık hassasiyetlerinin bir ölçüsü olarak kabul edilen penetrasyon indeksi (PI) değerleri de hesaplanmıştır. Daha sonra, saf ve modifiye bağlayıcıların yüksek sıcaklıklarda bünyelerinde meydana gelen uçucu madde kaybı dönel ince film etüvü deneyi (RTFOT) ile, bağlayıcıların işlenebilirlik özellikleri ise dönel viskozimetre (RV) deneyi ile belirlenmiştir. Fiziksel test sonuçlarına göre, SK katkısıyla bağlayıcıların sertleşme eğiliminin arttığı ve penetrasyon sınıfının B 100/150 olarak değiştiği görülmüştür. Ayrıca, SK katkısıyla bağlayıcıların sıcaklık hassasiyetlerinin azaldığı bu bakimdan en uygun oranın %15SK olduğu görülmüştür. RV sonuçlarına göre, SK katkısıyla bağlayıcıların işlenebilirliklerinin azalarak karıştırma ve sıkıştırma sıcaklıklarının yükseldiği görülmüştür.
- MakaleAçık Erişim2021Production and Characterization of Palm Oil Based Epoxy Biocomposite by RSM Design
Şahal, Hakan; Aydoğmuş, Ercan
In this research, some physical and chemical properties of the biocomposite obtained from synthesized epoxy modified palm oil (MPO) and epoxy resin have been characterized. The experimental study plan is made according to Response Surface Methodology (RSM) and biocomposites with different MPO rates are obtained. The chemical bond structure of MPO and epoxy biocomposite has been evaluated with Fourier Transform Infrared Spektrofotometre (FTIR). The experimental, and RSM model results obtained, the density of the biocomposite rise as the MPO rate increases. It is determined that the Shore D hardness of the biocomposite is inversely proportional to the MPO rate by mass. The thermal conductivity coefficient and thermal stability also rise with the rate of MPO (wt.%) in the biocomposite. In the thermal degradation experiments of the obtained biocomposite, it is observed that the thermal stability of the composite goes up as the MPO rate rises. Activation energies are calculated using the Flynn Wall Ozawa, Kissinger, and Coats Redfern models. The activation energies calculated for the 9th, 2nd, and 13th experiments according to the Flynn Wall Ozawa method are approximately 139.65, 143.56, and 145.28 kJ/mol, respectively. The functionwith the highest R2 value has been determined according to the Coats Redfern method, and the deviation in Flynn Wall Ozawa and Kissinger model results was below 7%.
AtıfOpenAlex25TR Dizin2İncele - MakaleAçık Erişim2021The Investigation of Production Errors and Remedies Arising from the Mold and Material Used in the Plastic Injection Production Line
Taşgın, Yahya; Gökkoruk, Ali
Plastic injection molding is widely used in all areas of the industry. The most important reason for this is that seamless plastic products in desired shapes and sizes can be easily produced with injection molds. Plastic products are exposed to many different parameters during molding. Therefore, it is aimed to create correct production methods by seeing the effect of molding parameters. The purpose of this study was to determine the fast and correct method and minimizing the errors by detecting the manufacturing defects that may occur during the production of materials with different properties with plastic injection machines beforehand. As a result of this study, the problems caused by the air remaining in the mold during the production phase, the problems caused by the turbulence that may occur during the flow of the liquid raw material, the problems that occur in the areas where the flow paths overlap, the reasons for product loss, especially in thin-section parts, the adhesion of the part to the female mold, the product with burr, as well as problems such as distortion and gaps were determined and solutions were provided.
AtıfOpenAlex2TR Dizin1İncele - MakaleAçık Erişim2021PLC ve SCADA Kullanılarak Bir Orcik Üretim Sisteminin Otomasyonu
Gencer, Cetin; Üstündag, Aybıke
Orcik, Elazığ yöresinde üzümden ya da duttan elde edilen şıranın un ve özel bir toprakla bulamaç haline getirilipceviz dizili ipin bu bulamaca istenilen kalınlığa göre bir veya daha fazla kez batırılıp güneşte kurutulmasıyla elde edilenyöresel bir üründür. Bu çalışmada, Türkiye'de tüketiminin yanısıra Avrupa ülkelerine de ihraç edilen orciğin fabrikaotomasyon sistemi ile üretimine yönelik bir benzetimi yapılmıştır. Doğal klasik yöntemlerle üretilen orciğin her birüretim aşaması ele alınarak Programlanabilir Mantıksal Denetleyici (PLC) otomasyon sistemi ile tasarımı yapılmış veSCADA üzerinde benzetimi gerçekleştirilmiştir. Elektrikli makineler, hızla büyüyen otomasyon hızının bir sonucuolarak sektörün bir parçası haline gelmiştir. Geleneksel endüstriyel işlemler makinelerin manuel çalıştırılmasıyla olur vebu işlemler manuel müdahaleye bağlıdır. Bu süreç zaman alıcı ve pahalıdır. Endüstrilerdeki yönlendirme görevlerininotomatikleştirilmesi verimliliği arttırır. Minimal insan müdahalesiyle PLC gibi otomasyon araçları kullanılaraktekrarlayan sürecin otomasyonu, geliştirilmiş verim, azaltılmış işletme maliyetleri, geliştirilmiş üretim hacimleri, dahaiyi kalite kontrol ve endüstriyel güvenlik sağlanır. Tasarlanan sistemle, orcik üretiminin klasik yöntem yerine PLCtabanlı otomasyon sistemine geçişi amaçlanmıştır.
- MakaleAçık Erişim2021Reuse of Industrial Metal Wastes as Partial Replacement of Aggregates in Mortar Production
Gülmez, Nihan
Sustainable waste management is becoming more and more important in the construction industry due to increasing waste costs as well as environmental effects. As a result of increasing level of wastes and environmental damage, the use of these wastes has become the focus for beneficial construction activities and sustainable industrial applications. This study presents experimental results on the effect of industrial wastes on the performance of cementitious mixtures. The scope of this study, therefore, was to assess the effect of waste aluminium on physical and mechanical properties of cement based mixtures prepared in different compositions. Consistency, bulk density, porosity, absorption, flexural and compressive strength tests were carried out on mixtures produced by using waste aluminium aggregates in different percentages instead of fine aggregate. Results showed that mixtures prepared with 4% aluminium aggregates had the highest water absorption and porosity. With the addition of %1 lathe waste, it was observed that the flexural behavior of mortar was maximum and the optimum percentage for flexural strength was noted. In addition, when mixtures produced with the same percentage of aluminium were compared, the amount of binder played a significant role on both compressive and flexural strength. Results have shown that to incorporate aluminium into mixtures can be a suitable solution for recycling in industrial applications.
AtıfOpenAlex5İncele - MakaleYalnız künye2021Scopus SJRQ1Investigation of Some Metal Accumulation Ability of Phragmites australis from Poultry Slaughterhouse Wastewaters
Topal, Murat
In this study, the bioaccumulation of some metals by Phragmites australis plants exposed to poultry slaughterhouse wastewater was investigated. For this aim, Mo, As, Cd, Se, Cu, Zn, Cr, Ba, Ti, Fe, Al, and Mn metals were determined in slaughterhouse wastewaters, P. australis plants, and sediment samples. The uptake of metals by P. australis was investigated. Also, BCF and TF values were calculated and compared with reference plant values. The maximum metal accumulation in P. australis plants exposed to poultry slaughterhouse wastewaters was 5900% for Al and 33.5% for Mn when compared with reference plant values. According to the BCF values, P. australis was bioaccumulative for Mo, Se, and Al. As a result, it was determined that P. australis plant can be used in the remediation of metals found in poultry slaughterhouse wastewaters and would be a good accumulator.
AtıfScopus2WoS1OpenAlex4İncele - MakaleYalnız künye2021Scopus SJRQ1Experimental design approach for ultra-fast nickel removal by novel bio-nanocomposite material
Ince, Olcay K.; Aydogdu, Burcu; Alp, Hevidar; Ince, Muharrem
In the present study, novel chitosan coated magnetic magnetite (Fe3O4) nanoparticles were successfully biosynthesized from mushroom, Agaricus campestris, extract. The obtained bio-nanocomposite material was used to investigate ultra-fast and highly efficient for removal of Ni2+ ions in a fixed-bed column. Chitosan was treated as polyelectrolyte complex with Fe3O4 nanoparticles and a Fungal Bio-Nanocomposite Material (FBNM) was derived. The FBNM was characterized by using X-Ray Diffractometer (XRD), Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDS), Fourier Transform Infrared spectra (FTIR) and Thermogravimetric Analysis (TGA) techniques and under varied experimental conditions. The influence of some important operating conditions including pH, flow rate and initial Ni2+ concentration on the uptake of Ni2+ solution was also optimized using a synthetic water sample. A Central Composite Design (CCD) combined with Response Surface Modeling (RSM) was carried out to maximize Ni2+ removal using FBNM for adsorption process. A regression model was derived using CCD to predict the responses and analysis of variance (ANOVA) and lack of fit test was used to check model adequacy. It was observed that the quadratic model, which was controlled and proposed, was originated from experimental design data. The FBNM maximum adsorption capacity was determined as 59.8 mg g−1. Finally, developed method was applied to soft drinks to determine Ni2+ levels. Reusability of FBNM was tested, and the adsorption and desorption capacities were not affected after eight cycles. The paper suggests that the FBNM is a promising recyclable nanoadsorbent for the removal of Ni2+ from various soft drinks.
AtıfScopus11WoS11OpenAlex7İncele - MakaleYalnız künye2021Scopus SJRQ2The assessment of basic blue 41 textile dye decolorisation using the Fenton process: response surface methodology optimisation and toxicity evaluation
Tanyol, Mehtap; Cikcikoglu Yildirim, Nuran; Tatar, Sule; Serdar, Osman; Yildirim, Numan
The biochemical biomarkers (Catalase (CAT), glutathione s-transferase (GST), cytochrome P4501A1 (CYP1A1450) activities and glutathione (GSH), malondialdehyde (MDA) levels) of D. polymorpha exposed to the basic blue 41 (BB41) solutions for 24 and 96 h before and after the Fenton process (FTP) were evaluated to investigate the efficiency of the FTP. The optimum conditions for the removal of BB41 were set using central composite design (CCD), which is a response surface methodology (RSM) module in the Design-Expert® software. The optimal conditions were found to be 27.87 min, 3.49 mg/L, and 0.04 for reaction time, initial BB41 concentration, and Fe2+/H2O2 molar ratio, respectively, resulting in maximum (99%) removal efficiency. After FTP, the MDA and GSH levels decreased significantly during the 24 and 96 h. CAT activities were increased after treatment. No statistically significant changes were observed in the CYP1A1 levels after FTP. GST activities decreased during 24 h but increased during 96 h after FTP. CYP1A1450, catalase, GST activities and MDA, GSH levels of D. polymorpha are useful biomarkers to evaluate the efficiency of FTP. This study suggests that BB41 dye must be further treated after the FTP to minimise the ecotoxicological risk.
AtıfScopus8WoS6OpenAlex8İncele - MakaleAçık Erişim2021Scopus SJRQ2Towards the circular economy: Analysis of barriers to implementation of Turkey’s zero waste management using the fuzzy DEMATEL method
Ayçin, Ejder; Kayapinar Kaya, Sema
Zero waste has an important position in the circular economy model in terms of manufacturing recyclable products instead of products to be consumed quickly, reducing the amount of waste, developing and implementing recycling/reuse technologies, and thus ensuring resource efficiency. A zero-waste strategy is one of the basic steps to achieve the goal of the circular economy. The number of studies conducted on Turkey’s zero waste management strategies referring to the circular economy is quite limited. To fill this gap in the literature, this study aims to identify the potential barriers which have an important role in zero waste management practices in Turkey. Through a broad literature review and expert opinions, 12 key barriers for zero waste implementation in Turkey have been defined in view of circular economy principles. Then, fuzzy DEMATEL methodology is employed to examine which is the most influential barrier affecting zero waste management success and to identify the interdependence of these barriers. The results indicate that uncertainty of the goals and tactics relevant to the circular economy and lack of financial and economic aid are key causal barriers that affect Turkey’s zero waste management.
AtıfScopus65WoS49OpenAlex85
İncele - MakaleYalnız künye2021Scopus SJRQ1Performance of marble powder on cementitious composites including waste steel chips as an additive
Gülmez, Nihan
The reuse of industrial waste materials in cement-based composites contributed to preventing increasing environmental problems and reducing production costs. This article examined the effectiveness of using recycled steel chips (Ast) from metal industry waste and waste marble powder (BMP) instead of cement and the possibility of obtaining eco-efficient specimen. While steel chips included in mortars as additives decreased workability, marble powder increased it. An increment in the level of substitution of steel chips resulted in a subsequent increase in water absorption percentages and apparent porosities of mortars. Maximum flexural strength was obtained in 2% steel chips-10% marble powder in waste system.
AtıfScopus16WoS15OpenAlex21İncele - MakaleAçık Erişim2021Scopus SJRQ3A novel macrofungus for the biosorption of hazardous dye and its reuse potential: Experimental design approach using response surface methodology
Ince, Olcay Kaplan; Alp, Hevidar; Ince, Muharrem; Onal, Ali
In the present study, a novel biosorbent, namely Agaricus campestris, was used for the removal of Methylene Blue (MB) from an aqueous medium. The biosorbent was characterized using fourier-transform infrared spectrometer spectra, scanning electron microscopy-energy dispersive X-ray, and thermogravimetric analysis. The influence of important process parameters including pH (4–7), temperature (25°C–35°C), contact time (15–25 min), and biosorbent amount (40–80 mg) on the uptake of MB solution were also optimized, which significantly affected the removal efficiency of MB. A central composite design (CCD) combined with response surface modeling (RSM) was carried out to maximize MB removal by A. campestris for the adsorption process. A regression model was derived using RSM to predict the responses and analysis of variance (ANOVA), and to check model adequacy lack of fit test was used. The A. campestris adsorption capacity was determined as 24.2 mg g–1. The ANOVA showed a high coefficient of determination (R2 = 0.9987). This study clearly revealed that RSM was one of the most effective and appropriate method for the optimization of operating conditions. The possibility of reusing A. campestris was also investigated and, as a result, it was found quite possible and showed high performance in the recovery of MB.
AtıfScopus2WoS1OpenAlex2İncele - MakaleYalnız künye2021Scopus SJRQ2Recovery of Cu(II) by Acorga M5640 After Leaching of Malachite Ore in Perchloric Acid Solutions
Demirkıran, Nizamettin; Tanaydın, Mehmet Kayra
Abstract: In the present study, the recovery of Cu2+ from the resulting actual leach solution after the leaching of malachite ore in perchloric acid solutions was examined by applying the solvent extraction method. The organic phase was prepared using Acorga M5640 and kerosene. The effects of the initial pH of solution, extractant concentration, Cu2+ concentration, temperature, and stirring speed on the extraction process were investigated. It was determined that the extraction yield increased with an increase in the extractant concentration, initial pH of aqueous solution, stirring speed, and temperature, and with a decrease in the concentration of Cu2+. To prevent or minimize Zn2+ transfer to the organic phase and to ensure maximum Cu2+ extraction from the aqueous phase, the optimal values for the initial pH of the aqueous phase, initial concentration of Cu2+, extractant concentration, temperature, and stirring speed were selected to be 1, 0.152 g/L, 4% (v/v), 25 °C, and 400 rpm, respectively. The stoichiometry and mechanism of the extraction process were determined applying the equilibrium slope method. The changes in the Gibbs free energy, enthalpy, and entropy were determined. The changes in these thermodynamic parameters were calculated to be − 3.87 kJ/mol, 64.67 kJ/mol, and 0.23 kJ/(mol K), respectively. Graphical Abstract: The extraction percentage of Cu2+ increases substantially when the initial pH of the leach solution increases from 0.1 to 1. The further increase in the initial pH above 1 does not create an increase in the extraction extent of Cu2+. When the initial pH of the leach solution is higher than 1, the amount of Zn2+ transferred from the aqueous phase to the organic phase increases significantly.[Figure not available: see fulltext.].
AtıfScopus7WoS5OpenAlex9İncele - MakaleYalnız künye2021Scopus SJRQ2Investigation of time effect on pectin production from citrus wastes with ohmic heating assisted extraction process
Sabanci, Serdal; Çevik, Mutlu; Göksu, Ali
Pectin is usually extracted by exposure to a high temperature and a specific pH value by conventional methods. However, due to reasons such as low energy efficiency of the process and damage to the pectin, alternative thermal and non-thermal methods are used in the pectin extraction process. In this study, the effect of different processing times (0, 5, 15, 30, 60, 120, 180 min) on pectin extraction was investigated for grapefruit, lemon, and orange samples at 80°C. Besides, it was determined that the electrical conductivity value ranged between 1.46–2.06 S/m during heating, the electrical conductivity value of the pH solution adjusted with sulfuric acid. Accordingly, it was figured out that the total amount of energy consumed increases as the process holding time increases. However, it was determined that there was a decrease in the average power value by turning on–off the system. Practical Application: Pectin is one of the additives used in many areas in the food industry. Pectin is now produced especially from agricultural waste peel. During this production, it is subjected to long processes at certain pH and certain temperatures. With the present study, determination of pectin yield over a wide period of time by using ohmic heating process and total ohmic heating energy was determined. In this way, it is thought that a serious contribution will be made to the literature and industry regarding different industrial agricultural waste peel (orange, grapefruit, lemon) during pectin production.
AtıfScopus36WoS31OpenAlex36İncele - MakaleAçık Erişim2021Scopus SJRQ1Thermoset powder coating wastes as filler in LDPE – Characterization of mechanical, thermal and morphological properties
Kismet, Yilmaz; Dogan, Akar; Wagner, Manfred H.
In this study, three different electrostatic powder coating wastes of thermoset structure were used as fillers for low-density polyethylene (LDPE). The mechanical, thermal, and morphological properties of these composites materials are reported. The thermoset powder coating wastes were hydrolyzed using water and alcohol, and then 10%, 20%, and 30% by weight of the deactivated wastes were mixed with LDPE, first in a mechanical dry mixer, and subsequently homogenized by melt compounding in an extruder at about 160 °C. Standard tensile test bars and plate-shaped samples were produced from these homogeneous compounds by injection molding. The effects of adding hydrolyzed powder coating wastes on the properties of LDPE were determined by mechanical, thermal, and morphological tests. Tensile strength and perforation threshold of the sample filled with powder coating wastes decreased to some extent compared to un-filled sample. However, an increase in izod impact and bending strengths has been observed. The results of this investigation demonstrate that powder coating wastes with thermoset structure can be used as fillers in LDPE.
AtıfScopus13WoS15OpenAlex16İncele - MakaleYalnız künye2021Scopus SJRQ1Sustainable supplier evaluation and transportation planning in multi-level supply chain networks using multi-attribute- and multi-objective decision making
Lo, Huai-Wei; Liaw, Ching-Fang; Gul, Muhammet; Lin, Kuan-Yu
Supplier selection and transportation planning are essential tasks in managing supply chain networks (SCNs). The choice of a supplier has a significant influence on the transportation planning of SCNs, as the transportation routes will change. A limited number of studies in the literature have addressed the supplier selection and transportation planning issues simultaneously. This study proposes a two-stage multi-criteria decision-making (MCDM) approach for sustainable supplier evaluation and transportation planning in multi-level SCNs. Initially, a supplier evaluation framework is proposed using the modified indifference threshold-based attribute ratio analysis (ITARA) and the performance calculation technique of the integrated multiple multi-attribute decision-making (PCIM-MADM) to determine the supplier's performance index. Subsequently, a multi-level SCN model is established, and the sustainable supplier selection and transportation planning problem is solved by the fuzzy multi-objective linear programming (FMOLP) method. A set of real-world data provided by a smart audio manufacturing company has been used to demonstrate the proposed approach. Decision-makers understand the importance of criteria through the weights constructed by the modified ITARA. Moreover, the results of the PCIM-MADM can effectively determine the supplier's ranking and provide improving strategies for underperforming suppliers. The augmented max–min technique of the FMOLP can produce a single optimal solution of the transportation allocation. The results show that our approach can effectively evaluate sustainable supplier performance and optimize transportation planning in SCNs.
AtıfScopus67WoS56OpenAlex64İncele - MakaleYalnız künye2021Scopus SJRQ1Production of Pectin from Lemon Peel Powder Using Ohmic Heating-Assisted Extraction Process
Çilingir, Seda; Goksu, Ali; Sabanci, Serdal
The ohmic heating process is known as homogeneous, efficient, and rapid heating. In the present study, it was aimed to analyze the extraction of pectin from lemon peel using ohmic heating, to evaluate the specific pectin production coefficient (SPPC, mg/kJ) and compared it with traditional pectin production (TPP). The extraction process was carried out at 3 different temperatures (70–90 °C), 3 different solid:liquid ratios (1:30, 1:40, 1:50 g/ml), 3 different extraction holding times (0–30 min), and a constant pH (pH 2 that adjusted with citric acid). From the results, extraction conditions affected the pectin yield. As the temperature and extraction holding time increased, the pectin yields increased. In general, the 30-min pectin yields of the ohmic heating-assisted extraction (OHAE) process were similar to the pectin yields obtained from the TPP under the same conditions. Performance evaluation of pectin production was made for 90 °C, and energy efficiency was found to be over 69% for 3 different solid to liquid ratios. It has been stated that as an alternative to the TPP method, the OHAE process can be applied.
AtıfScopus50WoS44OpenAlex53İncele
