WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Citation - WoS: 4Citation - Scopus: 4Effect of Oxidation on Mechanical Properties of Copper Nanowire: a Reaxff (reactive Force Field) Molecular Dynamics Study(Aip Publishing, 2023) Aral, Gürcan; Aral, Gürcan; 04.05. Department of Pyhsics; 04. Faculty of Science; 01. Izmir Institute of TechnologyNanostructures with high surface area to volume ratio, such as oxidized and coated Cu nanowires (NWs), exhibit unique mechanical properties due to their size and surface effects. Understanding the complex oxidation process of Cu NWs at nanoscale and quantifying its resulting effects on mechanical behavior and properties are significantly essential for effective usage of Cu NW devices in a wide range of applications in nanoelectronics. Here, we perform molecular dynamics simulations using ReaxFF (reactive force field) to investigate the oxidation process and mechanisms of [001]-oriented cylindrical Cu NWs and its contribution on the mechanical deformation behavior and material properties as a function of NW sizes. The relatively thin oxide CuxOy layer is formed on the surface of Cu NWs in an O-2 environment, creating a core/shell (Cu/CuxOy) NW structure that played a key role in governing the overall tensile mechanical deformation behavior and properties of Cu NW. The formation of oxide layer effects, including the resulting interface and defects, leads to a reduction in the initial dislocation nucleation barrier, which facilitates the onset of plasticity and stress relaxation, ultimately resulting in a negative impact on the tensile strength, Young's modulus, yield stress and strain, and flow stress when compared to pristine counterparts. It is worth noting that the tensile mechanical response and properties of the Cu NWs are highly dependent on the pre-existing oxide shell layer associated with the size of NW, determining the overall mechanical performance and properties of Cu NWs.Article Citation - WoS: 4Impact of Window-To Surface Area for Different Window Glass Types and Wall Orientations on Building Energy Performance: a Case Study for a School Building Located in Izmir, Turkey(Yıldız Teknik Üniversitesi, 2011) Yildiz, Yusuf; Durmuş Arsan, Zeynep; Ozbalta, Trkan Goksal; Arsan, Zeynep Durmus; 02.02. Department of Architecture; 02. Faculty of Architecture; 01. Izmir Institute of TechnologyThe opaque and transparent surfaces of buildings have an important role in the total percentage of energy loss or gain. Heat loss or gain from windows are dependent on the window-to-wall area ratio, the window glass type, and the type of window frame used. In the concept of energy efficient design, heat loss or gain from windows should be analyzed in detail in the early stages of building design by considering local climatic conditions. This study investigates a school building located in Izmir in Turkey, a city with a hot and humid climate. Various glass types with different glazing characteristics and number of layers, located in different parts of the buildings and with different window-to-wall ratios are analyzed and compared using building the energy analysis program "EnergyPlus". Results indicate that window-to-wall area ratios, wall orientation and glass types are important factors in the building's total energy consumption. When the window-to-wall area ratio is increased from 10% to 60%, the winter heating load of the building decreases in maximum amount on the south side of the building and reduces in minimum amount on the east side of the building. When summer cooling load is investigated the highest increase in energy consumption is found on the south side of the building. On the eastern and western sides of the building the effect of increased energy consumption value remains low. When the total energy consumption (cooling + heating) is considered, it is calculated that the east and west sides have the biggest total effect and the northern wall has the smallest total effect. When low emissivity glass is used instead of double layer glass, in terms of energy consumption the building side order of effect remains the same, although actual values differ. It is therefore clear that using energy analysis programs to analyse different factors within the energy consumption of buildings will be beneficial in creating energy efficient solutions. This can be carried out in the earlier stages of the architectural design of the buildings or at the renovation stages of existing buildings.