Physics and Astronomy: Recent submissions
Now showing items 401-420 of 520
-
Biomass Energy Dependence in South Africa: Are the Western Cape Province households descending the energy ladder after improvement in electricity access?
(Elsevier, 2020)South Africa was considered to have attained universal access to modern energy from 1994 to 2012. This meant that the number of households that moved away from the use of dirty energy to ... -
Controlled deposition of lead iodide and lead chloride thin films by low-pressure chemical vapor deposition
(MDPI, 2020)Lead halide thin films, such as lead iodide (PbI2) and lead chloride (PbCl2), are used as precursor films for perovskite preparation, which is frequently achieved by vacuum thermal evaporation but rarely by the low-pressure ... -
Synthesis and photovoltaics of novel 2,3,4,5-tetrathienylthiophene-co-poly(3-hexylthiophene-2,5-diyl) donor polymer for organic solar cell
(MPDI, 2021)This report focuses on the synthesis of novel 2,3,4,5-tetrathienylthiophene-co-poly(3-hexylthiophene-2,5-diyl) (TTT-co-P3HT) as a donor material for organic solar cells (OSCs). The properties of the synthesized TTT-co-P3HT ... -
Bio-synthesised black α-Cr2O3 nanoparticles; experimental analysis and density function theory calculations
(Elsevier, 2021)A selective single phase black α-Cr2O3 nanoparticles was bio-synthesised via simple straight-forward green synthesis approach. The process involves extraction of phytochemicals contained in peels of sweet potatoes. Extraction ... -
Electrochemical studies of Pd-based anode catalysts in alkaline medium for direct glycerol fuel cells
(MDPI, 2020)his study investigates the most effective electrocatalyst for glycerol oxidation reaction (GOR) in alkaline medium for five synthesized electrocatalysts, Pd, PdNi, PdNiO, PdMn3O4 and PdMn3O4NiO, supported on multi-walled ... -
Effects of alkali and transition metal-doped TiO2 hole blocking layers on the perovskite solar cells obtained by a two-step sequential deposition method in air and under vacuum
(Royal Society of Chemistry, 2020)Planar perovskite solar cells (PPSCs) have received great attention in recent years due to their intriguing properties, which make them a good choice for photovoltaic applications. In this work, the effect of alkali and ... -
Spin coating immobilisation of C-N-TiO2 Co-Doped nano catalyst on glass and application for photocatalysis or as electron transporting layer for perovskite solar cells
(MDPI, 2020)Producingactivethinfilmscoatedonsupportsresolvesmanyissuesofpowder-basedphoto catalysis and energy harvesting. In this study, thin films of C-N-TiO2 were prepared by dynamic spin coating of C-N-TiO2 sol-gel on glass support. ... -
Foreground contamination in Lyα intensity mapping during the epoch of reoinization
(IOP Science, 2014)The intensity mapping of Lyα emission during the epoch of reionization will be contaminated by foreground emission lines from lower redshifts. We calculate the mean intensity and the power spectrum of Lyα emission at z ... -
Pulsations and eclipse-time analysis of HWVir
(Oxford University Press, 2018)We analysed recent K2 data of the short-period eclipsing binary systemHWVir,which consists of a hot subdwarf-B type primary with an M-dwarf companion.We determined the mid-times of eclipses, calculated O–C diagrams, and ... -
Radon-222 measurements at Cape Point: A characterization of a 15-year time series
(National Association for Clean Air, 2018)The Cape Point (CPT) Global Atmosphere Watch (GAW) research station have been monitoring climatically significant trace gases for four decades. Among these is radon, a naturally occurring noble gas with a large continental ... -
Investigation of excited 0+ states in 160Er populated via the (p, t) two-neutron transfer reaction
(EDP Sciences, 2018)Many efforts have been made in nuclear structure physics to interpret the nature of low-lying excited 0+ states in well-deformed rare-earth nuclei. However, one of the difficulties in resolving the nature of these states ... -
Diurnal variations in global Joule heating morphology and magnitude due to neutral winds.
(Wiley, 2018)In the polar ionosphere, variations in Joule heating are significantly controlled by changes in plasma convection, such as that brought about by changes in the interplanetary magnetic field. However, another important ... -
Calibrating the James Webb Space telescope filters as star formation rate indicators
(American Astronomical Society, 2018)We have calibrated the 6.5m James Webb Space Telescope (JWST) mid-infrared (MIR) filters as star formation rate (SFR) indicators, using JWST photometry synthesized from Spitzer spectra of 49 low-redshift galaxies, which ... -
nIFTy galaxy cluster simulations – V. Investigation of the cluster infall region
(Oxford University Press, 2016)We examine the properties of the galaxies and dark matter haloes residing in the cluster infall region surrounding the simulated cold dark matter galaxy cluster studied by Elahi et al. at z = 0. The 1.1 × 1015 h−1M ... -
First ground-based observations of sprites over southern Africa
(Academy of Science of South Africa, 2018)Sprites are the optical signatures of electrical discharges in the mesosphere triggered by large lightning strikes associated with thunderstorms. Since their discovery in the late 1980s, sprites have been observed ... -
The observed galaxy bispectrum from single-field inflation in the squeezed limit
(IOP Publishing, 2018)Using the consistency relation in Fourier space, we derive the observed galaxy bispectrum from single- eld in ation in the squeezed limit, in which one of the three modes has a wavelength much longer than the other two. ... -
The Galactic halo pulsar population
(Oxford University Press, 2018)Most population studies of pulsars have hitherto focused on the disc of the Galaxy, the Galactic centre, globular clusters, and nearby galaxies. It is expected that pulsars, by virtue of their natal kicks, are also to ... -
Predicting the neutral hydrogen content of galaxies from optical data using machine learning
(Oxford University Press, 2018)We develop a machine learning-based framework to predict the Hi content of galaxies using more straightforwardly observable quantities such as optical photometry and environmental parameters. We train the algorithm on z ... -
Synergies between intensity maps of hydrogen lines
(Oxford University Press, 2018)We study synergies between Hi 21cm and Hα intensity map observations, focusing on SKA1- like and SPHEREx-like surveys. We forecast how well such a combination can measure features in the angular power spectrum on the ... -
Aligned metal absorbers and the ultraviolet background at the end of reionization
(Oxford University Press, 2018)We use observations of spatially-aligned C ii, C iv, Si ii, Si iv, and O i absorbers to probe the slope and intensity of the ultraviolet background (UVB) at z ∼ 6. We accom- plish this by comparing observations with ...