University of Botswana Research, Innovation and Scholarship Archive: Recent submissions
Now showing items 1-20 of 2172
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Photoionization cross-section in a GaAs spherical quantum shell: the effect of parabolic confining electric potentials
(Springer Nature, https://www.springer.com/, 2021-06-22)Theoretical study on binding energies due to a centred charged impurity and the associated photoionization cross-section (PCS) in a spherical shell are presented. This was achieved by solving the Schrödinger equation within ... -
Optical properties of GaAs nanowires with an electric potential that varies inversely with the square of the radial distance
(Hindawi, https://www.hindawi.com/, 2019-07-10)A theoretical investigation of optical properties of a cylindrical quantum wire (CQW) is presented. The properties studied were optical absorption coefficient (AC) and change in refractive index (CRI) of the quantum wire. ... -
Effect of an inverse parabolic confining electric potential on third harmonic generation in cylindrical quantum wires
(EnPress Publisher, LLC, https://systems.enpress-publisher.com, 2019)A theoretical investigation of the effect of an inverse parabolic potential on third harmonic generation in cylindrical quantum wires is presented. The wave functions are obtained as solutions to Schrödinger equation solved ... -
Probing semiconductor quantum well qubits and associated Shannon entropy using semi‑relativistic quantum mechanics
(Springer Nature, https://www.springer.com/, 2023-08-07)Electron states in GaAs, GaN and AlN quantum wells are studied by solving a semi-relativistic wave equation within the effective mass approximation. The quantum states are in turn used to probe the properties of two-level ... -
Diamagnetic susceptibility and optical properties of a spherical quantum dot: effects of the parabolic and the shifted parabolic potentials
(Springer Science+Business Media, LLC, part of Springer Nature, https://www.springer.com/journal/11082, 2019-06-22)Centred charge donor related diamagnetic susceptibility and optical properties of a spherical GaAs quantum dot are presented. In particular, effects of intrinsic parabolic and shifted parabolic potentials on these quantities ... -
The effects of cup-like and hill-like parabolic confining potentials on photoionization cross section of a donor in a spherical quantum dot
(EDP Sciences, Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature, https://www.springer.com/journal/10051, 2016-08-08)A theoretical investigation of the effects of hill-like and cup-like parabolic confining electric potentials on photoionization cross section (PCS) in a spherical quantum dot is presented. The hill-like and the cup-like ... -
Electron-LO-phonon intrasubband scattering rates in a hollow cylinder under the influence of a uniform axial applied magnetic field
(Springer Science+Business Media, LLC, part of Springer Nature, https://www.springer.com/journal/11082, 2021-11-06)Scattering rates arising from the interactions of electrons with bulk longitudinal optical (LO) phonon modes in a hollow cylinder are calculated as functions of the inner radius and the uniform axial applied magnetic field. ... -
Optical transition rates in a cylindrical quantum wire with an inverse parabolic potential
(Opast Group LLC, https://www.opastpublishers.com/journal/advances-in-theoretical-computational-physics, 2019-05-25)Electron transition rates due to interaction with circularly polarized light incident along the axis of a free-standing solid cylindrical nanowire are evaluated in the dipole approximation. In this case, the allowed optical ... -
Wildfires in Botswana and their frequency of occurrence
(Scientific Research Publishing Inc., https://www.scirp.org/journal/journalarticles.aspx?journalid=492, 2021-09-13)Fires play an essential part in the maintenance of the environment, but amplified fire activity often leads to adverse effects in the environment such as destruction of property and loss of life. Botswana has experienced ... -
Natural pigments as photosensitizers for dye-sensitized solar cells with TiO2 thin films
(Gazi University, https://www.ijrer.org/ijrer/index.php/ijrer, 2015)Dye-sensitized solar cells (DSSCs) were fabricated using four natural dyes extracted from the leaves of lemon (Citrus limon) and morula (Sclerocarya birrea) and flowers of bougainvillea (Bougainvillea glabra). Optical ... -
Electrophilicity of oxalic acid monomer is enhanced in the dimer by intermolecular proton transfer
(Royal Society of Chemistry, https://pubs.rsc.org/en/journals/journalissues/cp#!recentarticles&adv, 2017)We have analyzed the effect of excess electron attachment on the network of hydrogen bonds in the oxalic acid dimer (OA)2. The most stable anionic structures may be viewed as complexes of a neutral hydrogenated moiety HOA˙ ... -
Seismicity Study of Botswana from 1966 to 2012
(Scientific Research Publishing Inc., https://www.scirp.org/journal/ijg/, 2018-12-29)The history of Botswana’s major seismic events has been initiated by two earthquakes that occurred on the 11th of September and 11th of October 1952 with ML Richter magnitudes of 6.1 and 6.7, respectively, in the Okavango ... -
Local residents’ pride, tourists’ playground: the misrepresentation and exclusion of local residents in tourism
(Taylor & Francis (Routlegde), https://www.tandfonline.com, 2019-05-11)In most studies, Africans and other local residents in the Global South are often considered merely as hosts, and as a result, they are often misrepresented in shaping tourism in their own countries. Using Botswana as an ... -
Africans and protected areas: North–South perspectives
(Science Direct, https://www.sciencedirect.com, 2016-05)The paper critically explores why most black Africans do not visit protected areas. More specifically, the study examines non-Western tourists’ perceptions of nature and nature-based tourism in comparison to Western ... -
A review of the freshwater diversity in the Okavango Delta and Lake Ngami 1 (Botswana): taxonomic composition, ecology, comparison with similar 2 systems and conservation status
(Springer Link, https://www.springer.com/journal/27/, 2023-10-11)Freshwater organisms in the Okavango Delta and Lake Ngami (Botswana) provide direct and indirect benefits to people and the economy of the region. However, their existence could be potentially threatened by human activities ... -
Macrophyte species distribution, indices of biotic integrity, and sampling intensity in isolated Florida marshes
(Springer Link, https://link.springer.com, 2012)This study examined the distribution of wetland plants used in macrophyte-based index of biotic integrity (IBI) metrics to determine the effectiveness of zone sampling in assessing wetland condition. Using sampling data ... -
A vegetation-based hierarchical classification for seasonally pulsed floodplains in the Okavango Delta, Botswana
(Taylor & Francis, http://taylorandfrancis.com, 2011-12-11)A classification scheme is presented for seasonal floodplains of the Boro-Xudum distributary of the Okavango Delta, Botswana. This distributary is subject to an annual flood-pulse, the inundated area varying from a mean ... -
Species richness, diversity, density and spatial distribution of soil seed banks in the riparian woodland along the Thamalakane River of the Okavango Delta, northern Botswana
(Elservier, https://www.elsevier.com, 2021-12)Soil seed banks serve as reservoirs of seeds for subsequent regeneration of plants. Soil seed banks were investigated along the Thamalakane Riparian Woodlands (hereafter referred to as TRWs) of the Okavango Delta, northern ... -
Abiotic and biotic factors influencing the mobility of arsenic in groundwater of a through-flow island in the Okavango Delta, Botswana
(Elsevier, https://www.elsevier.com, 2014-10-10)The Okavango Delta of Botswana is a large arid-zone wetland comprising 20,000 km2 of permanent and seasonal floodplains and over 100,000 islands. It has been shown that island groundwater can have very high dissolved arsenic ... -
Phenology is the dominant control of methane emissions in a tropical non-forested wetland
(Springer Nature, https://www.springernature.com, 2022-01-10)Tropical wetlands are a significant source of atmospheric methane (CH4), but their importance to the global CH4 budget is uncertain due to a paucity of direct observations. Net wetland emissions result from complex ...