Selective detection of gases such as nitrogen dioxide (NO2), carbon monoxide
(CO), carbon dioxide (CO2), and various volatile organic components is necessary for air quality monitoring and safety. There are several metal oxide gas sensors (MOGS), but the focus of this study was Zinc Oxide (ZnO); an n-type MOGS. NO2, an oxidising gas was the target gas. The aim of this study was to establish...
We provide a study of the ratio of the top quark pair in association with a photon to the top quark pair to improve the precision of NLO QCD predictions for the proton proton $\rightarrow t\overline{t}$ process in the dilepton top quark decay channel. The top quark pair production cross-section has been measured at LO and NLO in proton-proton collisions at $\sqrt{s}$ = 13 TeV. The events with...
Modelling, machine learning and measurement, in collaboration with medical research, can lead to improved medical assays. In this project, lateral flow urine lipoarabinomannan (lam) assays are used as a diagnostic test for tuberculosis (TB) for people living with human immunodeficiency virus (HIV). It is used when patients may be too weak to produce sputum for standard TB tests such as...
Increased air pollution in the city and environment affects human health negatively. WHO data shows that 91% of the world's population lives in areas where air quality exceeds the safe levels. Carbon monoxide extremely toxic exposer to about 80-100 parts per million may have a high risk of serious health problems, according to the (NIOSH). In the market, the CO sensors are operated at high...
AlxGa1-xN epilayers prepared on sapphire substrates were assessed using Fourier Transform Infrared (FTIR) reflectance spectroscopy, photoluminescence (PL) and transmission electron microscopy (TEM). The aluminium mole fraction x of 5 samples grown at the NMU, and 3 samples grown at Linkopig were measured by using PL and FTIR. Formulae for the band gap of AlxGa1-xN as function of temperature...
A major upgrade to the High Luminosity Large Hardon Collider (HL-LHC) will increase the instantaneous luminosity by a factor 5 compared to the LHC. A complete redesign of the readout electronics system of the ATLAS Tile Calorimeter (TileCal) is required to cope with the new radiation levels and data bandwidth requirements envisaged for the HL-LHC. Numerous sensors will be...
Pentlandite (Pn) is an iron nickel sulphite with chemical formula of (Fe,Ni)9S8 and is contained mainly in Merensky Reef (~30%) of Bushveld complex. Pn systems are known to host precious metals in solid solutions or as intergrowths. However, the concentration of the precious metals hosted in the pentlandite structure and the effect of temperature and pressure on Pn-PGEs has not been...
Spatial Light Modulators have received a great deal of attention due to their ability to tailor the amplitude, phase and (in some cases) the polarisation of light. They are ubiquitous to applications that include free-space optics, optical fibre, underwater communication and metrology to name a few. Binarising a phase mask (or hologram) involves segmenting a ‘continuous’ 2π phase-shift into...
Incorporation of either metallic or non-metallic ions through implantation persuades structural imperfections which alters the electronic structure and possibly the optical properties of the implanted materials. 50 keV carbon ions were implanted into ZnO-NRs with varying fluences up to 3.0 × 1016 ions/cm2. The successful assimilation of carbon ions into the ZnO is primarily noted by a...
The University of Cape Town Physics Department recently acquired a Siemens Biograph 16 HiRez combined PET/CT scanner manufactured in 2005. Unlike older scanner models utilized by the department in Positron Emission Particle Tracking (PEPT), the Biograph scanner uses modern lutetium oxyorthosilicate (LSO) scintillators with a rapid response time, pixelated into a finer spatial grid. The new...
New protocol to achieve very long-distance and secure communication between two legitimate users (Alice and Bob) namely, the pseudo-random entangled photon based QKD protocol using a low-earth-orbit (LEO) type satellite as the photon source relay is proposed. We assume the combined type-I and type-II SPDC as photon source distributing entangled photons pairs to Alice and Bob, and the quantum...
Background:
Inelastic $\alpha$-particles scattering at energies of a few hundred MeV and very-forward scattering angles including $0^\circ$ has been established as a best tool for the study of the isoscalar giant monopole (IS0) strength distributions in nuclei across the periodic table. The present study describes a systematic investigation of the fine structure of the IS0 resonance in...
Cooperite has been found to have a natural floatability and therefore there are few reports on its interaction with reagents such as collectors. In this study we employed the density functional theory with dispersion correction (DFT-D) to investigate the interaction of sodium 2,6-dithio-4-butylamino-1,3,5-triazine (SDTBAT) and sodium normal butyl xanthate (SNBX) collectors with PtS (101)...
: Due to the rising demand of renewable energy, lithium-ion batteries have attracted much attention with Li2MnO3 being a perfect candidate to use as the cathode material. This is due to its high energy density and specific capacity. However, Li2MnO3 suffers from poor cycling stability and voltage fade which limits its practical application. In this work the built monoclinic Li1.2Mn0.8O2 is...
Lithium-air batteries have long been regarded as one of the best choices due to their high specific energy (11,400 Wh/kg). Catalysis is one of the most effective techniques used to improve electrochemical performance and influence the production of stable discharge products during cycling in lithium-air batteries. Despite several studies addressing the effect of catalysis in Li-air batteries,...
The Co9S8 is an important source of cobalt. The milling of the cobalt Co9S8 mineral exposes different surface and as such there are few or one surface that dominates during the crushing. The thermodynamic stable surface is less reactive and is of importance for mineral extraction. Computational method can determine the most stable surface and the preferred cleavage either through...
In this talk I review a control strategy for quantum systems where the control channel utilizes information about the system and then performs an actuation on the quantum state based on the state information [1]. The control channel is built on the polar decomposition of Kraus operators. I demonstrate that such a control channel still works even if the probability of the measurement outcome is...
Multiferroics are a class of materials exhibiting correlations in their ferroic orders (ferroelasticity, ferromagnetism, ferroelectricity, and ferrotorodicity). Light interaction with lattice vibrations is a powerful method to study the elastic properties of solids using surface Brillouin scattering (SBS). SBS is based on the inelastic scattering of photons by acoustic modes (phonons) to...
The Coulomb excitation of $^{66}$Ge has been performed for the first time using ``safe'' bombarding energies at the HIE-ISOLDE facility at CERN in July 2017. A particle-$\gamma$ coincidence experiment using the MINIBALL array and double-sided silicon detectors has allowed the determination of transitional and diagonal matrix elements in $^{66}$Ge, yielding new measurements of the reduced...
Transparent conducting oxides are of great interest in recent studies. Zinc Oxide thin films with different thicknesses were synthesized using thermal spray pyrolysis on p-type Silicon as the substrate. The prepared material was then annealed at 500 °C for 60 minutes. X-ray diffraction (XRD) was used to show what the preferred crystal orientation for the sample is, the grain size, the...
Micron-sized aerosol droplets can be trapped in air using a counter propagating optical trap. This allows the stationary droplet to be studied. In this work, the aim is to use the scattering of broadband white light from the trapped droplet and Mie theory to study the droplet’s morphology. To create the optical trap, two long working distance high numerical aperture microscope objectives focus...
The nuclear industry and its regulators have always prioritized safety and reliability in the operation of nuclear power plants. Thus the emphasis on the development, validation, and application of reliable predictive modeling capabilities for both normal and accident conditions. The Centre for Nuclear Safety and Security (CNSS) at the National Nuclear Regulatory (NNR) provides an important...
In this study, four layers of hematite (α-Fe2O3) thin films were prepared layer-by-layer on fluorine-doped tin oxide (FTO) using the dip coating method at withdrawal speed of 60 mm/min, annealed at 400-700oC for 2 hours, 30 minutes each layer. Following similar procedure additional samples were prepared and annealed at 700oC but different time intervals of 5,10 and 20 minutes for each of the...
Photovoltaic (PV) cells operating in the field generally have a degree of cell mismatch caused by; a) inherent mismatch from manufacturing shortcomings and b) different operational conditions, cell mismatch caused by external environmental factors such as partial shading or soiling and potential induced degradation (PID). This study focuses on the analysis of current-voltage (I-V)...
The separation of chalcopyrite and pyrite are usually done by taking advantage of the pH of the pulp. These are usually done by pH modifiers such as sodium hydroxide (NaOH) and lime (Ca(CO)2) and it has been reported that these gives different recovery performance. These pH modifies have not been completely explored from the computational aspect. In this study we employed the...
$\textit{α}$–CoV$_2$O$_6$ is a well-investigated one-dimensional spin chain system [1–4]. Most of the studies are focused on bulk polycrystalline and single-crystalline $\textit{α}$–CoV$_2$O$_6$. The compound orders antiferromagnetically below 15 K [2] and has been shown to exhibit field-induced metamagnetic transitions below T$_o$. This study investigates how the structural and magnetic...
Abstract: Any substance subjected to a variable electrical signal responds like a passive electrical circuit. The electrochemical impedance spectroscopy aims to characterise the equivalent circuit of a given substance. The characterization of the equivalent circuit is essential when the material should be used for battery or to determine any other application. In this work, the methodologies...
A full potential all-electron density functional method within generalised gradient approximation is used to investigate the electronic structure of copper sulphide. The electronic structure suggest a semi-metallic material with a zero band gap. Elastic calculations suggest a hard material with the bulk to shear modulus ratio of 0.381. The transport properties were estimated using the...
Neodymium-based permanent magnets (Nd2Fe14B) are the potential permanent magnets for use in various applications due to their high magnetic field strength and resistance to demagnetisation. These magnets have various applications in highly efficient energy conversion machines and devices such as wind turbines and electric vehicles due to their exceptional magnetic properties. However, they...
First-principles density functional theory calculations were performed to study the energetic stability, electronic and electrochemical properties of Li atoms on the H vacancies (VH) following a Line pathway as well as the zigzag pathway on a graphane sheet for LIBs. The results of Li on a single H vacancy VH1(L) revealed that it successfully induced interaction based on the improved binding...
In this work, we report the effect of zinc (Zn) and nickel (Ni) co-doping of hydrothermally synthesized hematite nanorods prepared on fluorine-doped tin oxide (FTO) substrates for enhanced photoelectrochemical (PEC) water splitting. Seeded hematite nanorods (NRs) were facile doped with a fixed concentration of 3 mM zinc and varied concentrations of 0, 3, 5, 7, and 9 mM of nickel. The doping of...
Using a novel regularization technique, we compute for the first time the NLO finite system size corrections to $2\rightarrow2$ scattering in massive $\phi^4$ theory. This is a useful first step to get insight into the effect of finite system sizes present in heavy-ion collisions at the LHC. Previously an equation of state for the relativistic hydrodynamics encountered in heavy-ion collisions...
Graphene is a 2-dimensional material that has received a lot of research attention over the last two decades as it is considered to be a revolutionary material for the future due to its superlative properties. Graphene has a zero band gap energy. This research work reports first principle calculations based on Density Functional Theory (DFT) to study the electronic and optical properties of...
B Phale1, PS Ntoahae1 and RR Maphanga2,3
1Department of Physics, University of Limpopo, Private bag x 1106, Sovenga, 0727 2Next Generation Enterprises and Institutions, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria, 0001
3National Institute of Theoretical Physics, NITheCS, Gauteng
Abstract
In this work, we present the first principles calculations for structural,...
The development of new rare-earth free Nd-Fe-B permanent magnet remains a serious issue for the transition to a green and sustainable world, as permanent magnets are an important component in the design and development of highly-efficient energy conversion machinery and devices. The effects of Ce and Dy on the electronic structures and magnetic properties of Nd2Fe14B have been studied using...
We use first principles calculations to characterize four types of dopant-vacancy point defects in the two dimensional material graphane for the purpose of quantum computing. The point defects we consider in this contribution are NcHv, NcCHv, NchHv, NchCHv and their various charge states. We derived the formation energies and other electronic properties of these point defects. Analysis of the...
The lightweight-based intermetallic have attracted much interest in the last decade as prospective structural materials for aerospace applications, since they maintain a large number of outstanding properties, such as high melting point, low density and high-temperature strength.However, their surface properties remain restricted and mainly limited at the atomic scale, therefore, surface...
The use of proton therapy decreases the damage to surrounding healthy tissue compared to traditional radiotherapy due to the existence of the Bragg peak where most of the beam's energy is deposited. However, secondary particles are produced externally along the beam line and within the patient due to protons interacting with the nuclei in the beam's path. Of particular interest are neutrons...
Scaling relations provide insight into galaxy evolution. While the Tully-Fisher relation may be one of the most well known HI-based scaling relations. A fundamental scaling relation for disc galaxies is the HI size mass relation. This relations shows a tight correlation between the diameter of a HI disc , $D_{HI}$, and its enclosed HI mass, $m_{HI}$. The correlation suggests a somewhat...
Hall coefficient (RH) measurements have shown to be an effective method in determining the number density, n=(qRH)-1, and the type of majority charge carriers at the Fermi surface (FS) [1-3] of Cr and its alloys. Parts of the Fermi surface sheets that are annihilated during antiferromagnetic (AFM) ordering in Cr based alloys have large...
We present an approach to search for heavy resonances. We focus particularly on the heavy resonances decaying into Z$\gamma$. The search is carried out in the di-lepton channel with two electrons~(muons) in the final state. This study is based on data from the ATLAS experiment gathered during the LHC Run-2, which corresponds to an integrated luminosity of 139 fb$^{-1}$. The goal is to set up a...
During ATLAS Phase-II Upgrade almost every electronics component of the Tile Calorimeter (TileCal) will be upgraded. The new on-detector readout electronics system requires a new portable system that will certify its correct functionality during the assembly, installation and maintenance periods. Portable readout module for tile electronics (PROMETEO) is an upgrade of the current MobiDICK...
Abstract: Multidrug-resistance (MDR) is one of the common challenges seen in cancer therapy. This phenomenon has led to the development of novel therapeutic strategies in which chemotherapeutic drugs are administered in combination with photodynamic therapy (PDT). PDT is a two-staged treatment that employs the administration of a photosensitizing agent which is followed by low laser...
The Ito calculus is a formalism which is used to study stochastic differential equations. Stochastic differential equations differ from ordinary and partial differential equations in that they contain randomly fluctuating terms which cannot be analysed using traditional calculus methods. In this talk, the Ito calculus will be explained and examples of it’s application to physics will be given
The precious metals are extracted as valuable by-products from sulphides and arsenides- platinum group minerals (PGMs). The growing use of precious metals in the mineral processing industry has developed a deep interest in extracting them from the PGMs. In this study, computational modelling technique, molecular dynamics (MD) is applied to investigate structural and physical properties of...
We have developed a machine learning-based generative model to estimate the kernel density of the data using the Gaussian kernel and then have generated additional samples from this distribution. This model uses scikit-learn to generate a list of particle four-momenta from the proton-proton collisions produced at the Large Hadron Collider (LHC). We demonstrate the ability of this approach to...
Kinetic analysis of thermoluminescence of α-Al2O3:C, an ultra-sensitive luminescence dosimeter, annealed at 1200 ⁰C for 1 hour is reported. The sample was annealed to modify the distribution of electron centres within it. Thermoluminescence was measured by heating the sample to 500 ⁰C at 1 ⁰C/s after 4 Gy beta irradiation. The glow curve reveals three peaks at 52 ⁰C (peak I), 188 ⁰C (peak II)...
Perovskites of cesium lead halide (CsPbX3, X = Cl, Br, I) have received a lot of attention due to their relative stability in comparison to their organic-inorganic counterparts. This study synthesized a thin film of cesium lead tribromide (CsPbBr3) by spin coating followed by dip coating and characterized it through a scanning electron microscope (SEM), ultraviolet-visible (UV- Vis)...
Density functional theory calculations where performed to study the behaviour of Li atom on self-healed graphane, focusing on the reconstructed region. The energetic stability, structural and electronic properties of different Li configurations where examined. Li atoms prefers to strongly bind at the octagon site transferring almost of its electronic charge towards its surrounding carbon...
KM Monareng1, RR Maphanga2,3 and SP Ntoahae1
1Department of Physics, University of Limpopo, Private bag x 1106, Sovenga, 0727 2Next Generation Enterprises and Institutions, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria, 0001
3National Institute for Theoretical and Computational Sciences, NITheCS, Gauteng, 2000
Abstract
With unprecedented amounts of materials...
Shape memory alloys (SMAs) are metallic materials that can revert to their original shape when exposed to various temperatures. These materials are used in applications such as actuators and aerospace due to their remarkable properties shape memory effect and pseudo-elasticity which occurs as a result of phase transformation. TiPt undergoes a reversible martensitic transformation from B2↔B19...
A series of layer-structured materials based on Transition Metals (TMs) doped MOFs derived Ni@Mn Yolk-shell were synthesized and successfully used as supercapacitor electrode materials for the first time. The as-synthesized materials exhibited exceptional electrochemical properties owing to the combined properties of its constituents, high surface area and good electrical conductivity of the...
The department of physics and Engineering at the University of Zululand (UNIZULU) is located in the middle of rural Zululand with communities that need to supplement the national energy grid with alternative energy sources. Most of these communities are rural or semi-rural who mostly harness solar energy by using standalone Photovoltaic (PV) battery charging systems. The University in its...
Quantum hybrid entanglement between two photons occurs when the two photons in question are entangled non-locally in different independent degrees of freedom. In our case, if we measure the polarization of one photon, we may infer what the spatial mode of the other will be, and vice versa. The resilience of polarization to turbulence and the ability to encode a large amount of information into...
The increasing demand for energy and the threat from global warming make electrical energy storage a worldwide policy objective. As such, sodium-ion batteries are currently evolving as a viable substitute for lithium-ion batteries due to the abundant availability and reasonable cost of sodium. Sodium transition metal oxides (NaMO2) with a P2 structure exhibit good Na+ ion conductivity and...
Neutron-rich indium isotopes ($Z=49$) near the well-known magic numbers at $Z=50$ and $N=82$ are prime candidates to study the evolving shell structure observed in exotic nuclei. Additionally, the properties of nuclei around the doubly magic $^{132}$Sn have direct implications for astrophysical models, leading to the corresponding neutron-shell closure nuclei around $N=82$ and the second...
The ISOLDE Decay Station (IDS) is an experimental setup at the ISOLDE facility at CERN dedicated to beta-decay spectroscopy for research into nuclear structure, nuclear engineering, and astrophysics. UWC has a leading experiment approved at IDS to investigate nuclear shape coexistence in $^{80,82}$Sr nuclei with the beta decay of $^{80,82}$Y. The study aims at measuring internal conversion...
Cancer affects individuals globally and breast cancer is the leading cancer in women in South Africa. The most common new cases of cancer include breast cancer, prostate, lung, and colorectal cancers. Photobiomodulation is a non-invasive
treatment that can be used in the treatment of tendinopathies, osteoarthritis, nerve injuries, wound healing, and some malignancies. Photobiomodulation has...
This study investigates the optical characteristics of hydrogenated crystalline bulk anatase Titanium dioxide (TiO2) using temperature-dependent photoluminescence (PL). The incorporation of deuterium (D2) is achieved by annealing in D2 atmosphere at a temperature of 300 oC. Temperature-dependent PL measurements are performed under continuous wave-laser excitation from 5.5 K to room...
In this work, erbium (Er3+) activated Yttrium orthovanadate-phosphate (YV0.5P0.5O4) nanomaterials were prepared by chemical bath deposition. The concentration of Er3+ was varied between 1 and 10 mole percentage. The structure, surface morphology, elemental composition and optical analysis were carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray...
In lower Earth orbit (LEO) a spacecraft and its electronics are exposed to an array of different radiation. One of the more destructive types of radiation that takes place in LEO is that of heavy ions. The most abundant heavy ion in the LEO range is atomic oxygen (AO), with a flux rate of $~10^{15} AO/cm^2s$ and energy up to $5eV$. To mitigate or reduce the degree of destruction, various...
Abstract: Resistive switching memory is an emerging memory that stores data using the two electrically switchable resistive states, viz., the high resistive state (HRS) as the OFF-state and the low resistive state (LRS), as the ON-state. ReRAMs have the simplest architecture comprising an active material (a thin film) sandwiched between two electrodes. This simple cell structure allows for...
The COVID-19 pandemic has disrupted teaching in a variety of institutions during 2020 and 2021. Online learning during those years became the core method of teaching the curriculum at universities. With COVID-19 running its course universities in 2022 had to return to a ‘’new normal” for teaching. The Department of Physics and Astronomy decided to have face-to-face classes for all its students...
The purpose of the work is having a solid and flexible environment of web interface, to rich that a well set environment is invaluable for Tile-in-One (Tio). Plugin based system for assessing the quality of data and conditions for ATLAS Tile Calorimeters is known as the Tile-in-One. The TiO is a collection of small sized independent web tools called plugins, designed to make it easier for a...
In this study we present the theoretical analysis and optimization of a 2D photonic crystal grating made from gold (Au) for sensing Plasmodium falciparum (Pf) parasites. The study is based on a previous reported plasmon sensor, which is the first experimental demonstration of Plasmodium detection in whole blood samples by directly probing antibody-antigen interactions with extraordinary...
We synthesized and electrospun mesoporous titanium dioxide (mp-TiO2) particles followed by calcination at 350 oC, 450 oC and 550 oC for 4 hours. Structure, morphology, porosity and optical properties were subsequently analyzed. X-ray diffraction (XRD) analysis revealed anatase and rutile phases of mp-TiO2, observed at calcining temperature of 450 oC and 550 oC, whereas as-prepared and mp-TiO2...
Doped transition metal nanoclusters have attracted significant interest for essential scientific research and various application purposes such as heterogeneous catalysts, electrochemistry and alloy designs. However, the current understanding of titanium bearing bimetallic nanoclusters is far from satisfactory. This is due to the complexity of the almost empty d band. The concept of metal...
This work reports on the structural and photoluminescence properties of Y2O3, Y2O3-AG: Eu3+ where AG = PO42-, SO42-, BO33-) nanophosphors synthesized via the chemical combustion method, annealed at 1100oC temperature for 4 hr. The crystal formation and the morphological behaviour of the Y2O3, Y2O3-AG: Eu3+ nanophosphors were verified through X-Ray diffraction (XRD), scanning electron...
The classical molecular dynamics is used to study Au and Ag nanoparticles focusing mainly on their structural stability. The structures were modelled at various temperatures in an NVT Evans ensemble. As such, the many-body Sutton-Chen potential was initiated to describe the interactions between atoms in both nanoparticles. Variation of total energy with temperature was investigated for both Au...
The structural, stability and vacancies properties of both defect free and defected 2D h-BNNSs were studied using the classical molecular dynamics (MD) approach. The calculations were performed in the NVT Evans and NPT hoover ensembles using the Tersoff potentials with the Verlet leapfrog algorithm to obtain reliable structural properties and energies for defect free, boron (B) and nitrogen...
Structural, optical and magnetic properties of combustion synthesized $Zn_{0.96}Ni_{0.01}Cr_{0.03}O$ and $Zn_{0.90}Ni_{0.05}Cr_{0.05}O$ have been investigated. X-ray diffraction (XRD) analyses confirm that samples are in the hexagonal wurtzite structure. No impurity peaks where detected in $Zn_{0.96}Ni_{0.01}Cr_{0.03}O$, while a weak secondary spike $ZnCr_2O_4$ phase $(2\Theta=43^o)$ was...
This work examines the assessment of systematic uncertainties and quantification of probable false signals on the fitting signal yield to Higgs-like production in the $Z\gamma$ final state, where the $Z$ boson decays leptonically. Several sources of systematic uncertainties for the measured observables are considered such as detector systematic uncertainties from detector effects and modelling...
A mobile radiation detection unit (MRDU) was developed to measure the radiation levels outside the iThemba LABS buildings, within the borders of the facility. The main attraction of this mobile unit is the fact that it is equipped with a LaBr3:Ce detector. This detector is superior to more conventional detectors (such as NaI:Tl) because of typically better spectral resolution, a high photon...
Energy storage is one major challenge in the development of viable storage devices to sustain many electronic devices. Hybrid supercapacitors combine the underlying structures of both batteries and supercapacitors in one physical unit. Graphene oxide (GO) has been suggested as a promising material for improved energy density in storage devices. In this study, GO was prepared by modified...
The research focused on the solution-based synthesis of a kesterite structure CZTS/CZTSSe. Copper zinc tin sulphide (CZTS)/CZTSe nano-powders were synthesized by means of solution-based method using copper chloride, zinc acetate, tin (II) chloride and Thiourea/Selenium as precursors. In this work nano-powders were synthesized in distilled water at different annealing temperatures in order to...
Nano-crystalline Zn0.5Mn0.5SmxFe2-xO4 (0 ≤ x ≤ 0.05) with average crystallite sizes varying between 12 and 17 nm were synthesized by the glycol-thermal process. XRD analysis confirmed a single-phase cubic spinel structure in all the compounds. Substituting a smaller Fe3+ ion with a larger rare-earth Sm3+ ion has affected the distribution of metal ions on tetrahedral (A) and octahedral (B)...
The L10 MnPt alloy is useful for magnetic recording and spintronic applications due to its high ferromagnetic stability. Previous studies showed that this alloy maintains its ferromagnetism at room temperature. In this study, first-principles method was used to investigate the effect of partial substitution of Mn in MnPt with ferromagnetic elements M (M= Fe, Ni). The ground-state properties of...
Abstract
The contribution of the Kruger National Park South Africa ecosystem to Carbon uptake and emission is highly variable across the years due to perturbations in vegetation cover as driven by large herbivores and inter annual climate variability. The quantification of the contribution of savanna ecosystems to the global carbon budget is still highly uncertain. This can account for by...
The synthesis of various stable metallic nanoparticles is increasingly becoming the focus and source of interest, this is due to their key features such as surface plasmonic activity, catalytic activity, and stability, amongst others, these therefore indicate their potential uses for several promising applications. This study describes the synthesis of $SnO_{2}$-coated Gold nanostructures,...
The unequal access to reliable internet connectivity between urban and peri-urban areas remains an issue of concern in many developing countries, including South Africa. A major reason for this so-called 'digital divide' is the unequal distribution of fibre infrastructure, which is usually due to economic or geographic reasons. This could be mitigated through the deployment of Free Space...
Most nuclei that exist in nature have deformed nuclear shapes. In the A = 130 mass region, nuclei are predicted to show triaxial nuclear shapes at low spins and therefore provide a rich testing ground for nuclear structure theories. Triaxial nuclei have unequal nuclear matter distribution along the three principle nuclear axes. Unlike axially symmetric nuclei, triaxial nuclei can rotate around...
Many renewable energy technologies are underperforming due to optimal energy collection and storage. Renewable energy generation is not available all the time, it happens when the wind blows or the sun shines, storage is an essential part. Lithium-ion (LI) batteries are dominating the market as storage devices with recent advances towards the electric vehicles and renewable energy storage....
Radiopharmaceuticals are used for therapeutic and diagnostic purposes. New radiopharmaceuticals are being developed and tested continuously. Some of these radiopharmaceuticals that could be used locally in the future include C-11, N-13, Cu-64, Ho-166, Sm-153, Ac-225 and Re-188. This work will describe how primary measurement methods at the National Metrology Institute of South Africa (NMISA)...
The Tile Calorimeter (TileCal) is the central hadronic calorimeter of the ATLAS experiment at the Large Hadron Collider (LHC). The LHC Phase-II upgrades will take place during the Long Shutdown 3 period (2026-2028), leading into the High Luminosity LHC (HL-LHC). The HL-LHC will have the capability to deliver up to five times the LHC nominal instantaneous luminosity in 2029. The TileCal Timing,...
Free-Space Optical (FSO) communication links have utilized Orbital Angular Momentum (OAM) modes as channels in Mode Division Multiplexing (MDM) systems. OAM modes suffer from turbulence-induced OAM crosstalk which degrades the performance of FSO communication links. OAM crosstalk flow with a certain extent of memory. Analytical models exist to predict OAM crosstalk are memoryless,...
Monazite is an ore mineral consisting of various rare earth elements (REEs), thorium (Th), and uranium (U). These components are utilized in numerous modern areas of technology, including metallurgy, catalysis, and magnetic fields. This monazite mineral has a notoriously stable structural conformation, making the conventional cracking process extremely inefficient. However, new innovative...
\begin{abstract}
Cadmium Tel lurid (CdTe) thin film can be synthesized by using low cost two electrode electrodeposition method in aqueous acidic solution contained cadmium acetate dihydrate1.M $ Cd (CH_{3}OO)_{2}, 2H_{2}O $ as cadmium precursor and 1ml Tellurium dioxide $TeO_{2}$ as Tellurium precursor on glass substrate(FTO) florin doped thin oxide with sheet resistance of 7...