Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Aydin, Handan(3)
- Ates, Mehmet(2)
- Cetin, Mehmet(2)
- Göktaş, Nebile Işık(2)
- Göktaş, Oktay(2)
- Güler, Seval Hale(2)
- Torgut, Gulben(2)
- Yüzüak, Ercüment(2)
- Yüzüak, Gizem Durak(2)
- Akgül, Melek(1)
- Akkurt, Nevzat(1)
- Akpolat, Mustafa(1)
- Aksu Canbay, Canan(1)
- Aksu, Önder(1)
- Akın, Erhan(1)
- Arslan, Zikri(1)
- Aslan, Naim(1)
- Aydin, Ilhan(1)
- Aydogdu, Burcu(1)
- Aydın, Ayşe Nur(1)
- Ayhan, Nagihan Karaaslan(1)
- Ağdaş, Mehmet Tevfik(1)
- Danabaş, Durali(1)
- Dehghanpour, Heydar(1)
- Doğan, Fatih(1)
- Erbay, Muhammed(1)
- Etli, Serkan(1)
- Guler, Omer(1)
- Güngör, Hiranur(1)
- Güray, Serhat(1)
- Gürler, Nedim(1)
- Kalay, Ece(1)
- Karaköse, Mehmet(1)
- Kaya, İsmet İnönü(1)
- Kismet, Yilmaz(1)
- Korkmaz, Adem(1)
- Kutlu, Banu(1)
- Mahmat, Aybars(1)
- Maraşlı, Muhammed(1)
- Polat, Berivan Yılmazer(1)
Yayınlar
- MakaleAçık Erişim2025Advances in Materials Innovations in Half Metallic Heusler Alloys for Structural Magnetic and Energy Spintronic Technologies
Özkul, İskender; Kalay, Ece; Guler, Omer; Aksu Canbay, Canan
Half-metallic Heusler alloys are promising materials for spintronic and thermoelectric applications. These alloys exhibit metallic conductivity in one spin direction while acting as insulators in the opposite spin direction, enabling nearly 100% spin polarization. This property is crucial for spintronic devices such as magnetic tunnel junctions (MTJs), magnetic random-access memories, and spin-based transistors. This study investigates the electronic, magnetic, and structural properties of Heusler alloys, focusing on their synthesis methods, atomic ordering, and modelling via density functional theory (DFT). DFT-based calculations serve as a key tool for predicting band structures, spin polarization, and magnetic properties. Additionally, the effects of disorder, strain, and compositional changes on material properties are analysed to explore performance optimization strategies. The potential applications of Heusler alloys in spintronic memory devices, thermoelectric energy conversion, and quantum technologies are also discussed. This work is presented as a review article and systematically compiles and interprets findings from the existing literature to provide a broad understanding of the topic. By integrating theoretical and experimental approaches, this study provides a comprehensive overview of the role of these materials in advanced technological applications.
- MakaleAçık Erişim2025Polipropilen lifli mikro betonlarda nano silika kullanımının etkisi
Akgül, Melek
Son yıllarda nano malzemelerin kullanımı diğer tüm uygulama alanlarında olduğu gibi çimento esaslı sistemlerde de önem arz etmektedir. Bu çalışma, harç ve beton uygulamalarında değerlendirilmiş olan nano malzemeler ve polipropilen liflerin mikro betonlarda eş zamanlı kullanımını amaçlamaktadır. Çalışma kapsamında üretilen 9 seri mikro betonun mekanik, fiziksel ve mikro yapı üzerindeki etkisi araştırılmıştır. Karışım tasarımlarında 3 farklı miktarda (0, 5, 10 kg/m3) nano silika ve 3 farklı miktarda (0, 1.2, 2.4 kg/m3) 12 mm uzunluğunda kırpılmış polipropilen lif kullanılmıştır. Referans karışımında kullanılan çimento miktarı 625 kg/m3 ve tüm karışımlarda kullanılan silis dumanı miktarı 125 kg/m3’tür. Üretilen ve kirece doygun su kürü ile olgunlaştırılan 9 seri mikro beton ile bir dizi fiziksel ve mekanik deney uygulanmıştır. Ayrıca 9 seri mikro betonu temsil edecek şekilde 6 seriden sağlanan numune örnekleriyle Taramalı Elektron Mikroskobu ve Enerji Dağılımlı X-Işını Spektroskopisi analizi yapılmıştır. Buna göre artan nano silika miktarı basınç ve eğilme dayanımı üzerinde doğrusal bir artış sunmaz, ancak 5 kg/m3 nano silika kullanımı eğilme ve basınç dayanımı üzerinde pozitif etkiye sahiptir. Ayrıca polipropilen lif kullanımı eğilme dayanımını artırmaktadır. Enerji Dağılımlı X-Işını Spektroskopisi verilerine göre artan nano silika miktarı C-S-H oluşumunu desteklemektedir. Taramalı Elektron Mikroskobu analizi görüntülerinde ise polipropilen lif miktarının karışımdaki dağılımı belirgindir.
- MakaleAçık Erişim2024Effect of Probiotic on Copper Nanoparticle Accumulation in Dreissena polymorpha
Serdar, Osman; Aydın, Ayşe Nur
Materials with dimensions between 0.1 and 100 nm are called nanoparticle (NP) materials. In recent years, the usage areas and quantities of NP materials have increased in parallel with the development of the industry. The need and usage areas of heavy metals such as Cu have also expanded in NP sizes. All these developments have led to problems on the ecosystem that are becoming more difficult to compensate. In this study, Zebra Mussel (Dreissena polymorpha) was chosen as a model to investigate the effect of probiotics on CuNP heavy metal accumulation. The model organism was exposed to three different concentrations of CuNP (5, 10, 50 mg/L) with probiotics and directly for 24 and 96 hours. CuNP accumulation amounts in D. polymorpha tissues treated directly and with probiotics were compared. The amount of accumulation in the test organism directly exposed to CuNP was higher compared to the groups administered with probiotics, but a statistically significant difference (p<0.05) was found only in the treatment group with the highest 24-hour concentration (50 mg/L). As a result, according to the findings obtained from the study, it has been determined that probiotics have positive developmental effects on aquatic organisms, as well as beneficial in the elimination of their accumulation in the organism.
AtıfOpenAlex4TR Dizin1
İncele - MakaleAçık Erişim2024ZnO Katkılı PCL+PVC-N3 Polimerlerinin Yapısal ve Optiksel Özellikleri
Aydin, Handan
Bu çalışmada poly (-caprolactone) (PCL) ile Poli(vinil klorür) (PVC-N3) blendleri üretilmiş olup, ZnO yarıiletken ilavesi ile oluşan kompozit araştırılmıştır. Öncelikle PCL ve PVC-N3 uygun bir çözelti içerisinde homojenizatör yardımıyla uzun süre ka-rıştırılarak elde edilmiştir. Ayrı bir yerde aynı çözücü ile karıştırılan ZnO hazırlanan blende eklenerek, değişen ZnO oranına göre polimer karışımında meydana gelen fark-lılıklar incelenmiştir. %5, %10, %15 oranlarında ZnO yarıiletkeni eklenmiştir. Hazır-lanan numunelerin yapısal sonuçları XRD ve SEM analizleri ile incelenmiştir. ZnO katkılı kompozitlerinin optik özellikleri UV-VIS spektrometresi ile karakterize edil-miştir. Numunelerin XRD (X-ışını Difraksiyonu) spektrumlarında hekzagonal wurtzite yapılı ZnO’in varlığını göstermiştir. SEM (Taramalı Elektron Mikroskopu) analizle-rinde ise yapıda kümelenmenin artması görülmüş olup; polimer blendinin katkıyla yüzey pürüzlülüğünü değiştirdiğini göstermektedir. Buna ilaveten; PCL+PVC-N3 karı-şımının ZnO ile optiksel etkileşimi UV-Vis spektroskopisi kullanılarak incelenmiştir. UV-Vis ölçümleri kullanılarak numunelerdeki yasak enerji aralıklarındaki değişmeler çeşitli uygulamalar için iyileştirme gösterecek şekilde belirlenmiştir. ZnO-PCL+PVC-N3 kompositlerinin optik enerji bant aralıkları artan katkı içeriğiyle değişiklik gösterdiği görülmüştür.
- MakaleAçık Erişim2024Effect of Ferro-Alloys on the Properties of High Entropy Alloy with FeCoNiMnMoV Composition Produced by Arc-Melting Method
Güler, Seval Hale
In this study, high entropy FeCoNiMnMoV and FeCoNiMn (Ferro Mo-Ferro-V) alloys were produced by arc melting method. After the arc melting process, the samples were annealed at 1000ᵒC under argon atmosphere for 15 hours physical and thermodynamic calculations were performed to determine the properties of the alloy. In the study, both alloys were characterized. For characterization, XRD, SEM, EDS and Micro hardness were taken from the samples. The aim of my study is to examine the effect of using low-priced starting materials on the microstructure of HEA. For this purpose, ferro-alloys were added to the alloy. As a result, similar properties were obtained for the microstructure of both alloys. However, it has been determined that the hardness of samples containing ferro-alloys decreases more due to their chemical composition, especially after heat treatment.
AtıfOpenAlex3İncele - MakaleAçık Erişim2024Biogenic Synthesis, Characterization and Degradation of Methylene Blue Dye of Zinc Oxide Nanoparticles from Different Zinc Salts Using Cinnamomum verum Extract
Aydogdu, Burcu; Unal, Ilkay
In this study, zinc oxide nanoparticles (ZnONPs) were synthesized using Cinnamomum verum extract from different zinc salts such as zinc acetate, zinc nitrate, zinc sulfate, and zinc chloride. The synthesized ZnONPs were characterized using X-ray diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR), and transmission electron microscopy (TEM). Additionally, The photocatalytic activities of ZnO nanoparticles were tested in the presence and absence of sunlight. Cinnamomum verum extract was analyzed for DPPH radical scavenging activity and total phenolic content (TPC). The study results showed that the type of zinc salt used significantly affects the morphology, size, and crystal structure of the ZnO nanoparticles. ZnONPs synthesized from zinc acetate (ZnONPsA) showed superior photocatalytic activity in the presence and absence of sunlight.
AtıfOpenAlex1İncele - MakaleAçık Erişim2024Investigation of tool wear and thrust force in drilling aisi 316 austenitic stainless steel using electrophoresis method
Mahmat, Aybars
Cutting tool costs are an important component of machining. For this reason, improving machining methods in machining affects the life of the cutting tool. Recently, various machining methods have been used to extend tool life by reducing cutting tool wear. One of these methods is electrophoresis-assisted processing. Electrophoresis-assisted machining is a non-traditional machining method created by the impact of abrasive nanoparticles on the machining area with the help of the generated electric field. Electrophoresis-assisted machining increases the machinability of difficult-to-machine materials with high strength and hardness properties compared to traditional machining methods. In this study, the impacts of various cutting parameters on the drilling performance of AISI 316 L stainless steel material were searched using electrophoresis-assisted drilling (EAD) and conventional drilling (CD) methods. In the study, SiC powder was used as nanoparticles in the solution obtained to create the electric field. Within the scope of the experiments, the effects of different machining methods, cutting speeds and feed rates on thrust forces and cutting tool wear values were experimentally examined. As a result of the investigations, the cutting tool wear and thrust cutting force obtained with EAD are better than CM. Increasing feed rate and cutting speed increased cutting tool wear in both machining methods. It has been determined that the thrust force decreases as the cutting speed increases, while it increases as the feed rate increases.Keywords: Electrophoresis, drilling, cutting force, tool wear, AISI 316
- MakaleAçık Erişim2023Investigation of Structural, Morphological and Magnetic Properties of Equi-molar Fe-Si-Cu/Nb (at.%) Nanocrystals Synthesized by Mechanical Alloying
Simsek, Tuncay; Güler, Seval Hale
In this study, equimolar nanocrystalline Fe-Si-Cu (at.%) and Fe-Si-Nb (at.%) alloys were synthesized under an Argon atmosphere by a mechanical alloying method. Experimental parameters were determined as 350 rpm, 10:1 BPR, 120 hours. Phase structures of the synthesized alloys were investigated by X-Ray diffractometry, morphology and elemental analyzes were investigated by SEM-EDS, and magnetic properties were investigated by vibrating sample magnetometer (VSM) technique at room temperature. The crystallite size of the Fe-Si-Cu alloy was found to be 102.3, 22.5, 15.9 and 8.6 nm at the beginning of grinding, after 30, 60 and 120 hours grinding, respectively, and the lattice strains were 0.164%, 0.510%, 0.672% and 1.165%, while the Fe-Si-Cu alloy For the Nb alloy, the crystallite sizes were calculated as 140.8, 42.9, 16.8 and 7.8 nm, and the lattice strains were calculated as 0.134%, 0.301%, 0.639% and 1.271%. According to the magnetism results, the saturation magnetization (Ms) of the Fe-Si-Cu (at.%) alloy was found to be 3146 emu/g, while the saturation magnetization of the Fe-Si-Nb (at.%) alloy was found to be 8.91 emu/g. It was determined that Nb addition to the Fe-Si alloy system caused an increase in the coercivity values.
- MakaleAçık Erişim2023Experimental investigation and numeric modelling of the impact performance of basalt fiber reinforced geopolymer concrete
Polat, Berivan Yılmazer; Güngör, Hiranur
Geopolymer concrete (GC) has been found to have better results than Portland cement concrete (PCC), including lower carbon dioxide emissions, higher compressive strength, and greater durability. The study aims to determine the effects of basalt fiber on GC due to the impact caused by the sudden loading effect. Samples were prepared with different mixing ratios for the experimental process, with PCC used as the control sample. Basalt fibers were added to the samples in three different ratios based on optimal mixing ratios determined through physical and mechanical tests, such as UPV (Ultrasonic Pulse Velocity), compressive strength, and flexural strength. Subsequently, fibrous samples were analyzed using SEM (scanning electron microscopy) and EDS (energy dispersive spectroscopy). A drop-weight experiment was conducted on GC plates measuring 50×50×5 cm, which contained two different fiber ratios that yielded the best mechanical and physical properties. The results were analyzed using numerical modeling methods. No changes in content were made. The sample with the highest impact resistance was found to be the 2% basalt fiber-reinforced GC, with a displacement value 21.21% lower than PCC. The language used is clear, concise, and objective, with a formal register and precise word choice. The text follows a logical structure with causal connections between statements and adheres to conventional academic formatting and citation styles. The ANSYS modeling results indicated an 89.63% similarity with the experimental data regarding the displacement values. Additionally, the study demonstrated that the inclusion of basalt fiber additives enhances the impact resistance of geopolymer concrete. Furthermore, numerical modeling can predict the impact behavior of concrete to a significant extent, eliminating the need for experimental processes.
- MakaleAçık Erişim2023Nadir Toprak Elementlerinin Karbon Elyaf Tozu Takviyeli Poliolefinlerin Akışkanlığına Etkileri
Kismet, Yilmaz; Güray, Serhat
Bu çalışmada, poliolefinler grubuna ait ticari birer termoplastik olan alçak yoğunluklu polietilen (AYPE), yüksek yoğunluklu polietilen (YYPE) ve polipropilenin (PP) akışkanlığı üzerine karbon elyaf tozunun ve nadir toprak elementlerinin etkileri incelenmiştir. Öncelikle mekanik olarak karıştırılan ağırlıkça %5, %10 ve %15 oranlarında karbon elyaf tozu içeren termoplastiklere ait karışımların eriyik akış analizleri yapıldı. Daha sonra AYPE, karbon elyaf tozu ve %90’nın üzerinde zenginleştirilmiş lantan ve seryum ile çözeltiler hazırlandı ve bunların akışkanlıkları incelendi. Bu çözeltiler hazırlanırken AYPE sentetik tinerde, lantan ve seryum ise su da çözündü ve sonra karbon elyaf tozu takviye edildi. Hazırlanan bu çözeltiler saf termoplastikler (AYPE, YYPE, PP) ile ayrı ayrı ağırlıkça %10, %20, %30, %40 ve %50 oranlarda karıştırılarak akışkanlık ve yoğunluk analizleri gerçekleştirildi. Bu şekilde hem karbon elyaf tozu hem de lantan ve seryum emdirilmiş karbon elyaf tozlarının termoplastiklerin akışkanlık ve yoğunluğu üzerine olan etkileri belirlenerek elde edilen sonuçlar grafiklerle açıklandı.
AtıfOpenAlex1İncele - MakaleAçık Erişim2023Nanosilika Modifiyeli Bağlayıcıların Tekerlek İzi Direnci ve Sıcaklık Hassasiyetlerinin Belirlenmesi
Akpolat, Mustafa
Bu çalışmada, Nanosilika (NS) katkısının bitümlü bağlayıcıların tekerlek izi ve sıcaklık hassasiyetine olan etkisi değerlendirilmiştir. Bu kapsamda saf ve 3 farklı orandaki (%2, %4 ve %6) nanosilika modifiyeli bağlayıcılar üzerine penetrasyon, yumuşama noktası, viskozite ve çoklu gerilmeli sünme geri dönme (MSCR) deneyi uygulanmıştır. Saf ve NS modifiyeli bağlayıcıların sıcaklık hassasiyetini belirlemek için geleneksel deney sonuçlarından yararlanılarak penetrasyon indeksi (PI) ve penetrasyon-viskozite sayısı (PVN) belirlenmiştir. Elde edilen sonuçlara göre, saf bağlayıcının nanosilika ile modifiye edilmesiyle bağlayıcının kıvamında azalma ve viskozitesinde artış sağlanmıştır. Bu sayede sıcaklık hassasiyeti daha düşük modifiye bağlayıcılar elde edilmiştir. Ayrıca MSCR deney sonuçlarına göre nanosilika modifiyesinin bütün sıcaklıklarda daha düşük Jnr değerleri vererek bağlayıcının tekerlek izi parametresini geliştirdiği daha ağır taşıt trafiklerine cevap verebileceği ve yüksek servis sıcaklıklarında kullanılabileceği belirlenmiştir.
- MakaleAçık Erişim2023Experimental investigation of engineering properties of silica sand filled mortars containing high doses of SWCNT
Subaşı, Serkan; Dehghanpour, Heydar; Maraşlı, Muhammed; Doğan, Fatih
Recently, great efforts have been made by researchers on the mixture of electrically conductive concretes that have been developed for different purposes. In this study, an experimental research was carried out on electrically conductive mortar mixtures especially for shell elements produced for building facade cladding. Six different mixtures were produced, including the non-conductive reference mixture. Single-walled carbon nanotube (SWCNT) was used as nano-sized conductive additive material. SWCNT was added at 0.2% and 0.3% of cement weight. SF was added to the same mixtures as another group at the rate of 4% by total weight. 2, 14, 28, 90 and 180 days electrical resistivities of the obtained conductive mortar samples were measured. As a non-destructive method, dynamic resonance testing was performed and the 28-day damping rates of the samples were determined. Ultrasonic pulse velocity (UPV) and Leeb hardness tests were performed, respectively, by using other non-destructive testing methods to obtain information about the internal structure voids and surface hardness of the samples. SWCNT, which causes low machinability and therefore internal structure voids, caused a decrease in compressive strength and flexural strength, as well as a significant increase in electrical conductivity.
AtıfOpenAlex1İncele - MakaleAçık Erişim2023Reclaim of Wrecked Bi-Te Based Materials In Peltier Modules In Thermopower Properties By Mechanical Milling
Yüzüak, Ercüment; Cetin, Mehmet; Yüzüak, Gizem Durak
We thoroughly evaluated the effects of various treatments on the structural and electrical properties of the two as-cast materials, “Sb-doping Bi-Te (p-type)” and “Se-doping Bi-Te (n-type)” which are frequently present in abandoned Peltier modules. To investigate the thermoelectric properties of Bi2Te3-based materials, waste alloys characterized by electrical conductivity using the hot-end method. Alloys were purified by performing arc melting on a water-cooled copper crucible in a vacuum of at least 10-3 mbar, with five times melting sessions to assure homogeneity. A single and long milling period of 144 hours is applied. After the compressing operation, the resulting discs with nanostructures were annealed for an hour at 600 K under vacuum conditions. The discs' structural properties were characterized using X-ray diffraction (XRD) and their surfaces and stoichiometries were determined using scanning electron microscopy with an energy dispersive feature. The Seebeck coefficient of the nanoparticle formed n-type Bi-Te based sample is -35.3 μV.K-1 and p-type Bi-Te based sample is 100 μV.K-1 (15% of mean error margin). It was found that a notable improvement was attained in comparison to the initial state with the addition of nanoparticles.
- MakaleAçık Erişim2023Self-Powered Mechanical Energy Sensor Application of SnO2/Ag and PMMA/ITO Nanocomposites via Triboelectric Effect
Yüzüak, Ercüment; Cetin, Mehmet; Yüzüak, Gizem Durak
The triboelectric nanogenerator is a state-of-the-art device for addressing the growing problem of meeting the world's ever-increasing energy needs by converting mechanical energy into electrical energy. Using the popular semiconductor SnO2 nanostructured thin films as a triboelectric layer over contact regions, as opposed to polymers with lesser performance, increases the output power and life time of nanogenerators. In order to design a triboelectric nanogenerator, deposited thin film SnO2 is used as a friction layer with Ag electrode after heat-treatment at 623 K with a contrary layer of PMMA poly (methyl-methacrylate) with ITO electrode. The structural and electrical properties were analyzed by using scanning electron microscopy (SEM), electro-impedance spectroscopy (EIS) and atomic force microscopy (AFM) measurements. The increased output power of the triboelectric nanogenerator is attributed to the nanoscale PMMA contact charge created by tunneling electrons in the SnO2/Ag nanocomposite thin film layer. Due to its proximity to the PMMA/ITO surface, the SnO2/Ag layer causes electron field emission, and tapping the SnO2/Ag layer may result in electron cloud overlap. Similar to a semiconductor/insulator interface, the Fermi level of SnO2 plays a crucial role in electron transport. The system efficiency stated as a touch detector in a conventional keyboard that generates its own power is revealed in part by an analysis of its operating state up to the 4V.
AtıfOpenAlex2İncele - MakaleAçık Erişim2023Deep Learning-Based Automatic Helmet Detection System in Construction Site Cameras
Korkmaz, Adem; Ağdaş, Mehmet Tevfik
Ensuring worker safety in high-risk environments such as construction sites is of paramount importance. Personal protective equipment, particularly helmets, plays a critical role in preventing severe head injuries. This study aims to develop an automated helmet detection system using the state-of-the-art YOLOv8 deep learning model to enhance safety monitoring in real-time. The dataset used for the study consists of 16,867 images, with various data augmentation and preprocessing techniques applied to improve the model's robustness. The YOLOv8 model achieved a 96.9% mAP50 score, outperforming other deep learning models in similar studies. The results demonstrate the effectiveness of the YOLOv8 model for accurate and efficient helmet detection in construction sites, paving the way for improved safety monitoring and enforcement in the construction industry.
AtıfOpenAlex15TR Dizin3İncele - MakaleAçık Erişim2023Demir oksit (Fe2O3) nanopartikülünün Allium tuncelianum (Tunceli Sarımsağı) kök ucu hücrelerindeki mitotik etkisi
Tasar, Neslihan
Dünya nüfusunun hızla artmasıyla birlikte ivme kazanan endüstriyel faaliyetler ve doğal kaynakların bilinçsiz tüketimi çevre kirliliğine sebep olmaktadır. Nanopartikül kullanılarak elde edilen malzemeler birçok alanda kullanılmaktadır. Tıp alanında kullanılan cihazlar, gıda üretimi ve paketlenmesi, elektronik, enerji üretimi ve kozmetik bu alanların başında sayılabilir. Nano-endüstriyel faaliyetler sonucunda demir oksit nanopartikülü (Fe2O3 NP) kullanımının artışıyla birlikte bu NP’ün toprakta, suda ve havada birikeceği düşünülmektedir. Bu çalışmada, değişik dozlarda hazırlanan (125, 250 ve 500 ppm) 20-40 nm Fe2O3 NP’ lüne maruz bırakılan ve indikatör bir organizma olan Allium tuncelianum (Kollmann) Özhatay, B.Mathew & Şiraneci (Tunceli sarımsağı) bitkisinin kök meristem hücrelerindeki mitotik etkisinin ortaya çıkarılması amaçlanmıştır. Fe2O3 NP’lü, genetik materyal kaybı, yapısı bozulmuş profaz, yapışıklık, metafazda kromozom gruplaşmaları, yapısı bozulmuş metafaz, yapısı bozulmuş anafaz, fragment, kutupsal sapma, köprü, ileri gitme, asenkron bölünme, star anafaz, multipolarite, yapısı bozulmuş telofaz gibi bazı mitotik anormalliklere sebep olmuştur. Bütün bu sonuçlar göstermiştir ki Fe2O3 NP’ lü genotoksik ve klastogenik etkiye sahiptir. Kısaca bu sonuçlar, Organizmalar tarafından alınan Fe2O3 NP’ lünün hem organizma hem de bir üst tüketici için tehlike oluşturabileceğini göstermektedir. Yine bu bulgular organizmaları etkileyen Fe2O3 NP’ lünün, biyobirikiminin azaltılması için kontrollü olarak üretilmesi ve kullanılmasının sonuçta da güvenli bir şekilde bertaraf edilmesi gerektiğini açığa çıkarmaktadır.
- MakaleAçık Erişim2022Hidrotermal yöntem kullanılarak ZnO@Fe3O4 kompozit nanoyapıların sentezi ve karakterizasyonu
Aslan, Naim
Buçalışmada,ZnO@Fe3O4kompozitnanoyapılarhidrotermalyöntemkullanılarak sentezlenmiştir.Farklıoranlarda Fe3O4katkısıylaeldeedilennanoyapılarınyapısal karakterizasyonuiçinX-ışınıkırınımanalizigerçekleştirildiveherhangibirsafsızlıkpikine rastlanmadı. Morfolojik görüntülemede taramalı elektron mikroskobu (SEM) ve geçirimli elektron mikroskobu (TEM) kullanıldı.Nanoyapılarınmorfolojisinde Fe3O4etrafındaZnOnano taneciklerinindekoreedildiğianlaşılmıştır.ElementalanalizdeiseFe,ZnveOpikleri kaydedilmiştir. ZnO@Fe3O4nanokompozit yapıların bant aralığı enerjileri Uv-Vis spektromotresi aracığılıyla elde edilen absorbans datalarından elde edilmiştir. Nanoyapıların bant gap değerleri yaklaşıkolarak2-2.1eVaralığındahesaplanmıştır.ManyetiközellikleriseVibratingSample Magnetometer (VSM) kullanılarak tespit edildi ve Fe3O4katkı oranına bağlı olarak 3.76 emu/g ile 7.96 emu/g değerleri bulundu. Bu değerler sınırlı bir ferromanyetik özellik göstermesine rağmen ZnO’nun sahip olduğu gelişmiş optik, elektronik özelliklerinden dolayı optoelektronik ve medikal görüntüleme uygulamalarında önem arz etmektedir.
AtıfOpenAlex9İncele - MakaleAçık Erişim2022Green Synthesis of Gold Nanoparticles Using Aqueous Extract of Asphodelus Aestivus, Coating with Chitosan Biopolymer and Cytotoxicity Studies
Ates, Mehmet; Yilmaz, Ersen; Erbay, Muhammed
The green synthesis of gold nanoparticles (Au-NPs) was carried out by pouring the aqueous extract of East Anatolian origin Asphodelus aestivus plant onto aqueous gold metal ions and reducing them via single-step one- pot method. The absorption peak of the synthesized nanoparticles gave a maximum at 575 nm. All the X-ray diffraction peaks at 2θ = 38.25 , 44.46 , 64.64 and 77.20 that index to (111), (200), (220), and (311) planes verify the successful synthesis of Au-NPs. Mostly spherical shape particles showed a homogeneous distribution with size range 20±5 nm are measured using TEM. From the FTIR spectrum, the peaks are seems to be related to phenolic compounds, flavonoids, benzophenones, terpenoids and anthocyanins which assume that they could act as the reducing agents. The plant extraction, one-pot, single-step method used is environmentally safe without the role of synthetic materials which is highly potential in mild and green synthesis applications. The Au-NPs were coated with chitosan biopolymer in aquatic solution medium and verified by SEM. Then, cytotoxic investigations of the biosynthesized Au-NPs were carried out by HUVEC cells. Au-NPs were showed toxic effects on cell culture, even if in a small amount. However, chitosan biopolymer coating increased cell viability.
AtıfOpenAlex3İncele - MakaleAçık Erişim2022The effect of using phase change materials and examining the aspect ratio in an air-cooled system of a plate battery connected to a solar system
Akkurt, Nevzat
Lithium-ion batteries are widely used in the electronics industry to store electrical energy. One of the challenges with these batteries is that they heat up during operation, which can damage the battery. For this reason, this paper simulates the cooling process of a plate-type (BTP) lithium-ion battery pack. To control the temperature of the battery (T-B), a laminar air flow and a phase change material (PCM) are used. The PCM is placed in a heat sink around the battery. This evaluation is performed temporarily for four different dimensions of the PCM pack. The hot outlet of this system is used to provide the thermal energy required for a small residential building (THE) at a mild temperature. The BTP was also simulated using COMSOL. The results show that the use of larger heat sinks can increase the maximum (MAX) and average (AVE) temperature of the battery. The minimum T-B occurs at different times for the smaller PCM heat sinks. Also, when using a heatsink with a larger PCM volume, it takes longer for the PCM to fully solidify. A BTP with 5 or 50 battery cells can provide up to 3% or 30% of the THE required for the building.
- MakaleAçık Erişim2022Evaluation of curing time for micro concrete mixes containing silica fume, nano-silica and fly ash
Etli, Serkan
Within the scope of the study, research on the use of silica fume (SF), nano silica (NS) and fly ash (FA) together or separately in the production of micro concrete is presented. It is aimed to examine the changes in mechanical properties because of water and air curing in mixtures produced using SF, FA, and NS. While cement dosage and water/binder ratio in the mixtures were chosen as 670 kg/m3 and 0.53 respectively, the amount of SF, FA and NS was limited to 150 kg/m3 in total. In the study, samples were produced using 40x40x160 mm prism molds. All samples were divided into two different groups after 7 days of water curing and water (1st group) and air (2nd group) were applied up to 56 days. Flexural and compressive strength tests were performed on the water and air cured specimens for 7-56 days and 28-56 days, respectively. In addition, the porosity and unit volume weight values of the samples were examined. The results show that both flexural and compressive strengths of micro concretes increased after 28 days thanks to water curing.
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