7 sonuçlar
Arama Sonuçları
Listeleniyor 1 - 7 / 7
Yayın Güvenli ve sürdürülebilir nanoteknoloji uygulamaları(Rüştü Uçan, 2018-04-01) Gül, AyşenurSon zamanlarda, nanoteknolojinin gündelik hayatımızda yer alması ile tekstil, kaplama, katalizör, tıp, elektronik, gıda, enerji gibi çeşitli sanayi ve teknoloji sektörlerinde önemli değişiklikler ve gelişmeler kaydedilmiştir. Nanoteknoloji, pek çok malzemenin yapısında son derece küçük ölçekte değişiklikler yapabilmeyi sağlayan bir bilim dalıdır. Ayrıca, mevcut malzemelerin belirli bir amaca yönelik olarak geliştirilebilmesi ve daha hafif, reaktif olmayan ve daha güçlü ve dayanıklı alternatifler üretmek de mümkündür. Araştırma laboratuvarlarının yanı sıra endüstriyel ve ticari alanlarda da nanoteknoloji uygulamaları artmaktadır. Nanomalzemeler ile çalışan işçiler ve işverenler bu maddelere solunum, cilt ile temas veya yutulma yoluyla maruz kalabilirler. Fakat, nanomalzemelerin çevre ve insan sağlığı üzerindeki riskleri ile ilgili henüz yeterli veri oluşmamıştır. Bunun yanında, bu malzemelerin bazıları, yüksek yüzey alanlarına, çok düşük ateşleme enerjilerine ve sıcaklıklara bağlı olarak iş yerinde patlama ve yangın çıkartabilir. Bu raporun amacı, nanomalzemelerin potansiyel sağlık etkisini ve iş yeri tehlikelerini tanımlamak ve bu materyallerin güvenlik kültürü ve kontrol yöntemlerini geliştirmektir.Yayın Preparation and characterization of mesophase pitch based carbon foam produced at low pressure(Springer, 2015-08) Gül, Ayşenur; Yardım, Mehmet FerhatThe morphological changes during carbon foam synthesis depend on the process pressure and temperature, melting temperature, and viscosity of the mesophase pitch. This study is focused on interpreting the foaming mechanism and analysing the preparation process of mesophase pitch based carbon foams. Results have shown that more homogenous and better structured carbon foams were derived under higher pressure. The carbon foams exhibited higher density and strength at this pressure.Yayın Bir vaka analizi: Hastanelerde hizmet veren taşeron yemek şirketlerinde iş sağlığı ve güvenliği(Rüştü UÇAN, 2018-10-22) Akman, Ümran; Gül, Ayşenur; Ensari Özay, MügeEndüstrileşme ile birlikte sanayide taşeron yemek hizmeti veren firmalarda artış gözlemlenmektedir. Yemek şirketlerinin NACE kodu az tehlikeli olmasına rağmen hizmet verdikleri hastane NACE kodu çok tehlikelidir. Bu da çalışanların kendi çalıştıkları sektörün dışında hizmet verdikleri alanlara göre de tehlike ve risklerin değerlendirilmesi gerekliliğini göstermektedir. Bu çalışmanın amacı toplu yemek üretimi yapan şirketlerde çalışan ve o şirketlerden hizmet alanların yaşadığı riskleri belirlemek ve çözüm önerilerinde bulunmaktadır. Bu çalışmada kamuda sekiz hastaneye hizmet veren taşeron yemek şirketinde çalışanlarının yaşadığı tehlikeler incelenmiş, riskler belirlenmiş ve çözüm önerileri sunulmuştur.Yayın Effect of mechanically exfoliated graphite flakes on morphological, mechanical, and thermal properties of epoxy(Multidisciplinary Digital Publishing Institute (MDPI), 2024-11-11) Gül, Ayşenur; Kamali, Ali RezaCarbon-reinforced polymer composites form an important category of advanced materials, and there is an increasing demand to enhance their performance using more convenient and scalable processes at low costs. In the present study, graphitic flakes were prepared by the mechanical exfoliation of synthetic graphite electrodes and utilized as an abundant and potentially low-cost filler to fabricate epoxy-based composites with different additive ratios of 1–10 wt.%. The morphological, structural, thermal, and mechanical properties of these composites were investigated. It was found that the thermal conductivity of the composites increases by adding graphite, and this increase mainly depends on the ratio of the graphite additive. The addition of graphite was found to have a diverse effect on the mechanical properties of the composites: the tensile strength of the composites decreases with the addition of graphite, whilst their compressive strength and elastic modulus are enhanced. The results demonstrate that incorporating 5 wt% of commercially available graphite into epoxy not only raises the thermal conductivity of the material from 0.223 to 0.485 W/m·K, but also enhances its compressive strength from 66 MPa to 72 MPa. The diverse influence of graphite provides opportunities to prepare epoxy composites with desirable properties for different applications.Yayın Enhancement of epoxy properties through graphene nanofillers produced in molten salt: morphological, thermal and mechanical characterization(Springer, 2026) Gül, Ayşenur; Kamali, Ali RezaThis research investigates the enhancement of epoxy resin properties through the incorporation of graphene nanoplatelets (GNPs), synthesized via the molten salt exfoliation method, as nanofillers. The study evaluates the morphology, thermal conductivity, and mechanical performance of the resulting nanocomposites. Electron microscopy reveals a high density of reactive edge sites in the graphene material, which enable bonding with epoxy groups during curing. It also shows a uniform dispersion of graphene nanoplatelets (GNPs) within the epoxy matrix, leading to reduced void formation and enhanced interfacial bonding. A notable improvement in the physical and mechanical properties of the epoxy was observed with the addition of GNPs up to 1.0 wt%. At this concentration, Young’s modulus increased by approximately 42% (from 2.9 to 4.2 GPa), while thermal conductivity, compressive strength, and tensile strength improved by around 41%, 9%, and 32%, respectively. These findings indicate that the integration of GNPs into epoxy resin significantly enhances both thermal and mechanical performance, positioning the nanocomposites as strong candidates for advanced structural applications.Yayın The effect of carbon materials on the properties of epoxy(Flogen Star OUTREACH, 2015-12-23) Gül, Ayşenur; Kamali, Ali; Fray, DerekNanostructured carbon composites can play important roles in lithium and other batteries. Preparation and characterisation of such composites are therefore important in further development of batteries. Carbon nanostructures including carbon nanotubes, nanoparticles and graphene can economically be produced in molten lithium chloride. The present work reports the influence of the molten salt synthesised carbon nanostructure filler and commercial graphite on the properties of epoxy resin. The carbon materials were incorporated into the polymer matrix to make composites. The carbon-epoxy composites produced were then characterized by a variety of techniques including scanning electron microscopy, x-ray diffractometry, and dynamic mechanical analysis. The thermal and mechanical properties of the nanocomposites were also measured. It was found that addition of carbon materials can enhance the properties of the epoxy matrix considerably.Yayın Safety and health concerns with lithium-ion batteries(Flogen Star OUTREACH, 2015-12-23) Gül, AyşenurThe lithium ion batteries consist of positive (inorganic lithium-intercalating compound and negative (lithium-intercalating carbon) electrodes and have an organic liquid electrolyte (a lithium salt in an organic liquid). They store lots of energy in a small and light package. Lithium-ion batteries are widely used in cordless communication technologies and equipment such as laptops, cell phones, and other mobile devices. Despite lithium ion batteries are produced with the high safety standards, plenty of incidents have been reported because of fire and explosion of lithium ion batteries in electronic devices or large vehicles and facilities. Therefore, lithium-ion batteries are optimized to store and release energy with respect to environmental, health, and safety issues. This work summarizes potential hazards and safety recommendations for their commercialization.
