68 research outputs found
The Effect of Atmospheric Pollution on Building Materials in the Urban Environment
Nowadays atmospheric pollution affects not only the urban environment in general, but building materials, which leads to their corrosion, in particular. The article discusses the regularities of the adhesion process of particulate matter (dust) on the vertical surfaces of buildings and structures, which are made of various building materials. On the basis of experimental studies, regression dependences of the adhesion of urban dust on different vertical surfaces from random determining factors were obtained. Thus, by studying the regularities of pollution of urban environment objects, made of various building materials, it is possible to achieve their preservation, since they demonstrate the architectural and design features of various historical periods of the country's development
Universal radiation tolerant semiconductor
Radiation tolerance is determined as the ability of crystalline materials to
withstand the accumulation of the radiation induced disorder. Nevertheless, for
sufficiently high fluences, in all by far known semiconductors it ends up with
either very high disorder levels or amorphization. Here we show that gamma/beta
double polymorph Ga2O3 structures exhibit remarkably high radiation tolerance.
Specifically, for room temperature experiments, they tolerate a disorder
equivalent to hundreds of displacements per atom, without severe degradations
of crystallinity; in comparison with, e.g., Si amorphizable already with the
lattice atoms displaced just once. We explain this behavior by an interesting
combination of the Ga- and O- sublattice properties in gamma-Ga2O3. In
particular, O-sublattice exhibits a strong recrystallization trend to recover
the face-centered-cubic stacking despite the stronger displacement of O atoms
compared to Ga during the active periods of cascades. Notably, we also
explained the origin of the beta-to-gamma Ga2O3 transformation, as a function
of the increased disorder in beta-Ga2O3 and studied the phenomena as a function
of the chemical nature of the implanted atoms. As a result, we conclude that
gamma/beta double polymorph Ga2O3 structures, in terms of their radiation
tolerance properties, benchmark a class of universal radiation tolerant
semiconductors
Ruthenium ion modification of glassy carbon: Implication on the structural evolution and migration behaviour of implanted Ru atoms
DATA AVAILABILITY : Data will be made available on request.Please read abstract in the article.Organization for Women in Science for the Developing World (OWSD) and the National Research Foundation (NRF) of South Africa.http://www.elsevier.com/locate/nimbhj2024PhysicsNon
Effects of implantation temperature and annealing on structural evolution and migration of Se into glassy carbon
Please read abstract in the article.The AST&D scholarship from the Tertiary Education Trust Fund (TETFund), Nigeria, and the Postgraduate Bursary from the University of Pretoria, South Africa.http://www.elsevier.com/locate/sssciehj2023Physic
Comparison of the structural properties of Zn-face and O-face single crystal homoepitaxial ZnO epilayers grown by RF-magnetron sputtering
Homoepitaxial ZnO growth is demonstrated from conventional RF-sputtering at 400 °C on both Zn and O polar faces of hydrothermally grown ZnO substrates. A minimum yield for the Rutherford backscattering and channeling spectrum, χmin, equal to ∼3% and ∼12% and a full width at half maximum of the 00.2 diffraction peak rocking curve of (70 ± 10) arc sec and (1400 ± 100) arc sec have been found for samples grown on the Zn and O face, respectively. The structural characteristics of the film deposited on the Zn face are comparable with those of epilayers grown by more complex techniques like molecular beam epitaxy. In contrast, the film simultaneously deposited on the O-face exhibits an inferior crystalline structure ∼0.7% strained in the c-direction and a higher atomic number contrast compared with the substrate, as revealed by high angle annular dark field imaging measurements. These differences between the Zn- and O-face films are discussed in detail and associated with the different growth mechanisms prevailing on the two surfacesThis work has been performed within “The Norwegian
Research Centre for Solar Cell Technology” Project No.
193829, a Centre for Environment-friendly Energy Research
co-sponsored by the Norwegian Research Council and
research and industry partners in Norway and the Frienergi
program. R.S. acknowledges the partial support from the EU
7th Framework Programme Project No. REGPOT-CT-2013-
316014 (EAgLE)
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