In this work, the formation of oxygen-vacancy defect in 3d metals-doped TiO2 anatase and rutile structures is first investigated. The systematic calculations of formation energy, crystalline stability, band structure and density of state (DOS) of TiO2 samples of anatase and rutile doped with 3d transition metals with and without oxygen defect is done using FHI-aims as a software package based o...

this study purported to compare and contrast the use of self-mention and evidentials as two mtadiscourse features in opinion columns of persian and english newspapers. the theoretical basis of this study is the idea that metadiscourse features vary across cultural boundaries. for this purpose, 150 persian and 150 english opinion columns were collected based on three factors of topic, audience a...

The purpose of this study is to investigate the factors affecting TFP in the East and West Asia in order to discover the reasons for the difference in total productivity in each of these regions. For this purpose, factors affecting TFP, especially human capital and oil rents, were investigated using several static and dynamic models and forming two distinct groups from East and West Asia. The r...

The activities of human civilization have imposed a high burden on the environment since the beginning of history on a global scale. That is why energy producers and consumers need to think deeply about the role that energy plays to achieve sustainable development. In this context, the maintenance of the environment, which cannot be replaced, should be taken into account precisely. Rising energ...

among the low–dimensional allotropes of carbon, nanotubes and graphene have attracted very much attention from nano–science and nanotechnology specialists. they have been proposed as building blocks in nanometer device engineering. however, these structures are not defect–free. in this thesis, we focused on defective carbon nanotubes and graphene, and studied the effect of couple of very common...

abstract: country’s fiber optic network, as one of the most important communication infrastructures, is of high importance; therefore, ensuring security of the network and its data is essential. no remarkable research has been done on assessing security of the country’s fiber optic network. besides, according to an official statistics released by ertebatat zirsakht company, unwanted disconnec...