Structured light has gained in popularity of late, fueled by a toolbox for arbitrary control of light’s many degrees of freedom. Although this toolbox is very sophisticated and diverse, it is still primarily centered on single wavelength digitally controlled structured light, only recently expanding into broadband structured light modes. Here, tools are combined from Fourier optics with recent...
Thermochromic energy-efficient windows have been investigated intensively ever since the rise of an energy-efficient model for VO2-based windows. However, pure VO2 possesses an energetic difference of low-to-high-temperature infrared transmittance lower than 10% and visible transmittance at about 40%, which limits its commercial application as a coating material for smart...
The burden of tuberculosis (TB) infections is disproportionately high in low-income and resource-limited settings. This disparity exacerbates the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) My-cobacterium tuberculosis (Mtb), the bacterium that causes TB. Early detection and treatment of TB remain key strategies to reduce the spread and disease progression,...
High Temperature Reactors (HTRs), particularly the very high temperature reactor (VHTR), represents a significant advancement in nuclear reactor technology. Reactors operate at temperatures exceeding 1000 °C, which enhance the thermal efficiency and allow the potential for hydrogen production through thermochemical processes. In a VHTR, the generated impurities in the helium coolant can lead...
The density functional theory (DFT) is applied to systematically investigate the geometrical structure, electronic, mechanical, vibrational, and optical properties of half-Heusler HfSnPt in its cubic phase. To the best of one’s knowledge, many physical properties of this compound are still not well established or not yet investigated; such as phonon properties, mechanical behavior, thermal...
We present a browser-based simulation tool for Surface Plasmon Resonance (SPR) sensor modelling, developed using Python and Flask. The tool allows users to visualize reflectance curves based on selected or custom parameters, incorporating Drude models for metals and experimentally validated refractive index equations for biological media such as plasma and blood. Users can generate real-time...
The properties of the surfaces of materials play a crucial role in determining the behaviour and functionality of materials as the bulk properties, since they control the interaction between the substance and the external environment. They dictate how the material interacts with other substances, such as gases, liquids, or other solids. Many chemical reactions, especially heterogeneous...
The Pt-based materials are widely used in industries, including metallurgy, medicine, jewellery, fuel cells, and hydrogen evolution reactions due to their excellent electrochemical properties. However, in its pure form, platinum (Pt) is soft, thus prone to surface scratching, a concern in jewellery applications. Hence, alloying to enhance its mechanical properties is key to improving scratch...
Mn-Ir bimetallic alloys have emerged as promising candidates for spintronic applications due to their attractive properties, such as high thermal stability, large exchange bias fields in Antiferromagnetic/ferromagnetic (AFM/FM) layers. However, the properties of certain phases remain unexplored. In this study, we employed ab initio simulations using the CASTEP code within Materials Studio 2020...
Research has increasingly shifted towards alternative battery chemistries due to the high costs, Lithium depletion and safety concerns of Li-ion batteries. Mg-ion battery chemistry has gained attention as a promising alternative in rechargeable battery technology due to the bivalency of Mg2+ ions. In this chemistry, Vanadium Pentoxide (V2O5) is projected to a suitable cathode material for...
In this theoretical study, the structural, electronic and optical properties of KBX3 (B = Ge, Sn; X = Cl, I) based perovskites are systematically studied using first principle density functional theory. Self-consistent calculations are performed using plane wave ultra-soft pseudopotential technique and the generalized gradient approximation of Perdew–Burke–Ernzerhof scheme is used to treat the...
In large-scale particle physics experimentation, maintaining precise control of diverse environmental parameters across complex detector subsystems constitutes a fundamental operational requirement, directly impacting data acquisition integrity, component longevity, and systemic stability. Contemporary slow control infrastructures predominantly employ static threshold parameters, deterministic...
This study employed ab-initio density functional theory (DFT) with Grimme’s D3 dispersion correction to investigate the bulk and surface properties of hematite. The Hubbard U parameters 5.0 eV was adopted which gave a band gap of 2.55 eV and lattice parameters of a = b = 5.045 Å and c = 13.774 Å, which were in good agreement with experimental values (band gap: 1.9–2.6 eV; lattice parameters: a...
Iron aluminide is a metal alloy with unique properties, including high strength and temperature resistance, making it suitable for applications in aerospace and energy sectors. FeAl alloy has a good specific modulus, strength-to-weight ratio, and corrosion resistance to oxidation, sulfidation, and other forms of corrosion. These iron-aluminides showed a major embrittlement mechanism at room...
A formula to calculate the refractive index n of AlxGa1-xAs was proposed by Adachi in 1985. This formula takes into account the variation of the band gap Eg of AlxGa1-xAs as function of the Al mole fraction x. Consequently there are two equations for the calculation of the band gap, viz. for x less than 0.45 and x from 0.45 to less than...
ABSTRACT
Electricity usage and demand has risen tremendously over the years and so has its price. This has resulted in the need for less expensive, viable and ecologically acceptable means of producing energy for electricity. Currently, the primary source of electricity and power in South Africa is sourced from fossil fuels which has impacts on global warming. Bongumusa Secondary School in...
The O3-type Li2MnO3 layered cathode material shows great potential for large-scale energy storage in electric grids and vehicles due to its high capacity and energy density. However, it tends to undergo structural changes from a layered to a spinel configuration during charge cycles. Recent advances in surface coating techniques have improved the electrochemical performance of these cathodes...
Solid electrolytes (SEs) offer high energy densities, are compatible with high-voltage cathodes, and possess high thermal and electrochemical stability. Amongst other SEs, LiTi2(PO4)3 (LTP) with the NASICON-type structure has captured significant interest as a better SE owing to its excellent chemical stability, environmental friendliness, and economic viability....
In this study the mixed phases BaAl2O4/MgAl2O4: 0.1 Tb3+ (BM:0.1% Tb3+) nanophosphors were prepared via the citrate sol-gel method. The structural and optical properties were investigated by varying the annealing period from 1 hour to 5 hours, while keeping the annealing temperature at 1000°c and the doping concentration of 0.1% Tb3+ constant. The phase quantification of the X-ray diffraction...
Crystal Field Theory (CFT) provides a fundamental framework for understanding magnetic transitions by elucidating the interactions between transition metal ions and their surrounding ligand fields. In complex oxides such as Sm₂MnB’O₆ (B’ =Mn, Ce and Ru), CFT plays a crucial role in correlating structural distortions, chemical bonding, and magnetic ordering. This work demonstrates how...
A facile aqueous chemical growth method was used to synthesize layered zinc hydroxide nitrate (ZHN) and subsequent thermal treatment of ZHN resulted in zinc oxide (ZnO) nanosheets. The SEM images of ZHN and ZnO show that the morphology of the two remain similar even after calcination at 400°C. The elemental composition of ZHN and ZnO was confirmed using EDS and the functional groups present in...
The present time includes all tools that can assist the human race to make things faster reducing effective time. In the era of Artificial Intelligence (AI) it is very important to find its applicability in the field of teaching particularly Physics. The present work aims at the discussion of all type of AI-based tools that can be useful for teachers and learners keeping in mind the the...
LiNiO2 (LNO) has emerged as a promising high-capacity cathode material for lithium-ion batteries (LIBs), offering a theoretical capacity of 270 mAh/g. However, its commercialisation is hindered by structural instability and rapid voltage degradation during cycling, primarily resulting from mechanical stress induced by phase transitions and volume changes. These effects lead to...
Iron sulphides minerals are used for metal extraction and present in various types of rock such as igneous, sedimentary, and metamorphic ones. Marcasite-FeS2, an iron sulphide mineral is ubiquitous in nature, its oxidation plays a vital role in acid mine drainage, mineral resource recov-ery, and photoelectric material applications. In this work, we employed atomistic simulations to...
The High Luminosity Large Hadron Collider (HL-LHC) is scheduled to commence operations in 2030, targeting a luminosity five times than that of the current LHC run. This substantial increase in luminosity necessitates significant upgrades to the LHC detector systems. The Phase-II upgrades of the ATLAS detector involve a complete upgrade to the low voltage power supply (LVPS) system of its Tile...
Understanding background radiation is essential for precision studies in any facility. This work investigates background contributions observed during radiative capture measurements at the low-energy nuclear astrophysics beamline (H-line) of the iThemba LABS Tandetron facility. The H-line is dedicated to studying the statistical properties of proton-rich isotopes via proton or alpha induced...
The rapid expansion of the solar photovoltaic (PV) sector has brought increasing attention to the sustainable management of decommissioned solar panels. This study investigates circular economy strategies for addressing the environmental and material recovery challenges associated with end-of-life (EoL) PV modules. Drawing on a review of current practices and policy frameworks, the paper...
ABSTRACT
Lithium-air batteries represent one of the most promising technologies for energy storage, characterized by their high energy density (1086 Wh/kg) and substantial specific capacity (3842 mAh/g). However, they experience a practical drawback that involves the production of unstable discharge products (LiO2, Li2O and LiO) resulting in battery degradation. Cobalt oxide (Co3O4) is...
In this study, we present a comparative analysis of deep neural networks (DNN) and XGBoost for the classification of γγ+τ final states to separate rare signal events from background using Monte Carlo data. The dataset is preprocessed to exclude energy-related features and focus on the kinematic variables of the first identified tau lepton (τ₁). A DNN model is a machine learning model that...
This study investigates the structural and morphological properties of pure and titanium-doped Li1.2Mn0.8O2 cathode materials through integrated computational modelling and experimental techniques. Titanium doping was chosen due to its ability to enhance structural stability, reduce capacity fading, and mitigate voltage decay in lithium-rich manganese oxides.. Molecular dynamics simulations...
Light-sheet fluorescence microscopy (LSFM) is a technique in which a thin plane of a sample is illuminated with a focused laser beam and the fluorescence signal is collected perpendicular to the optical axis. LSFM provides high quality images of samples, while reducing photodamage and photobleaching. However, the images generated with LSFM still suffer from aberrations and limited...
Cobaltite (CoAsS) possesses a similar structure to that of pyrite (FeS2), exhibiting a semiconducting behaviour. Its X-ray diffraction pattern has been shown to closely resemble that of FeS2 with the cleavage occurring along (100), (021), (111) and (110) planes in order of decreasing prominence. Cobaltite is commonly found in a variety of ore deposits, particularly in...
Lithium Sulphur batteries suffers from the low conductivity of S and the solubility of intermediary polysulfide species during cycling. It has been reported that Se and mixed SexSy represent an attractive new class of cathode materials with promising electrochemical performance in reactions with both Li ions. Notably, unlike existing Li/S batteries that only operate at high temperature, these...
Nickel reserves are expected to run out by 2030 which contribute to various industrial applications such as stainless steel, coinage, and rechargeable batteries. Pentlandite is the primary source of nickel as well as a major carrier of platinum group elements (PGEs). The flotation of pentlandite and nickel ore has always been performed using traditional xanthates, dithiophosphate and...
In this study, strontium hydroxyapatite (Sr5(PO4)3OH) doped with europium (Eu³⁺) and ytterbium (Yb³⁺) were successfully synthesized by combustion method. The structural, morphological, and optical properties of the phosphors were determined using X-ray diffraction (XRD), high resolution scanning electron microscopy (HRSEM), energy dispersive X-ray spectroscopy (EDS), and photoluminescence (PL)...
From hybrid (spin and orbital angular momentum) entangled states, topological structures emerge when one investigates the mapping of the spatial profile (orbital angular momentum) possessed by one photon to the spin angular momentum on the Poincarè sphere of the other photon. The extraction of topological invariants (in the field of photonics) has been primarily limited to 2-dimensional...
Sodium-ion batteries (SIBs) represent a cost-effective and sustainable alternative to lithium-ion batteries, especially in the context of large-scale energy storage applications. This study utilized first-principles calculations grounded in density functional theory (DFT) with a spin-polarized generalized gradient approximation (GGA + U), applying a U value of 4.0 eV for all transition metals....
Ruthenium-based alloys exhibit strong potential for aerospace applications. This study employs first-principles DFT calculations to examine the impact of pressure on the structural, electronic, mechanical, and phonon properties of Mn₃Ru in its A15 crystallographic phase. At zero pressure, Mn₃Ru has a negative formation energy of -0.64 eV, indicating thermodynamic stability. However, as the...
Mothiba Joy1, Solethu Nkosi1
1Department of Physics, University of Limpopo, Private bag x 1106, Sovenga, 0727, Polokwane, South Africa
2Next Generation Enterprises and Institutions, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria, 0001, South Africa
3National Institute for Theoretical and Computational Sciences, NITheCS, Gauteng, 2000, South Africa
Developing...
Of all the different types of batteries available and currently developed, lithium-ion batteries (LIBs) have gained a significant segmentation in the market and are the most promising and the fastest growing battery technology. However, the performance of any Li-ion battery greatly depends on the physical and chemical properties of the cathode material, which serves as a host for Li ions. As...
The Affordable Multiple-Aperture Spectroscopy Explorer Prototype (AMASE-P) is an innovative project aimed at improving high-resolution integral field spectroscopy for investigating ionised gas in the Milky Way and nearby galaxies. A critical component of AMASE-P is the fibre instrument cable (FIC), designed to efficiently transmit light from the telescope to the spectrographs. Compact fibre...
The longevity of spacecraft materials is severely impacted by the radiation-rich environment of Low Earth Orbit (LEO), which has led to the development of lightweight, radiation-tolerant coatings. In this work, a composite material consisting of graphene oxide the (GO) and poly(2,5-benzimidazole) (ABPBI) was synthesised by in situ polymerisation and characterized by X-ray diffraction (XRD) and...
Waste-to-energy conversion is contributing significantly in enhancing the economic growth and health quality in society. One of the technologies that utilized waste-to-energy transformation is biomass technology. The study focused on the development of a nonlinear multiple regression (response surface) model to predict the biogas production with input parameters being relative pH of slurry,...
Experimental studies have demonstrated that pure BaTiO3 can serve as a catalyst for hydrogen production via water splitting. However, its large energy band gap prevents activation under visible light. This study explores the potential of using visible light, the most abundant component of solar energy, to drive water splitting by modifying BaTiO3's electronic and optical properties through...
TiO2 nanoparticles (NPs) were synthesized using sol-gel method. The samples obtained were subsequently annealed at different temperatures from 450°C to 1200°C. The structural, optical, and morphological properties of TiO2 are investigated. The X-ray diffraction (XRD) results of as prepared revealed an amorphous structure. The annealed samples revealed a mixed phase of anatase and rutile, with...
Effect of hydrogen in the migration behavior of strontium implanted into SiC was investigated. Polycrystalline SiC samples were first implanted with 300 keV Sr ions to a fluence of 2×10¹⁶ ions/cm² at room and 350 oC. Some of the implanted samples were then co-implanted with hydrogen ions of 15 keV at RT and 350 oC, to the fluence of 1x1017
ions/cm-2. The samples were then annealed at 1000 oC...
The study presents the findings of the effect of ion implantation on pristine Copper Zinc Tin Sulphide (CZTS) thin films. The CZTS films were prepared by utilizing a two-stage process, i.e. e-beam deposition of metal precursors; Cu, Zn, and Sn followed by sulphurization process in the tube furnace at 500°C for 30 min. These samples were further implanted with 150 keV V+ ions utilizing...
FeCo alloy belongs to the category of intermetallic soft magnetic material. It exhibits the highest saturation magnetisation (~2.4 Tesla) among commercially available soft magnetic materials, along with high Curie temperatures (920–985 0C) and good mechanical strength which make it suitable for various applications. However, this alloy ‘s widespread applications are restricted...
Nanocrystalline Ni0.5Mg0.5RE0.03Fe1.97O4 (RE =Dy3+, Pr3+, and Sm3+) nanoferrites were synthesized using the hydrothermal method. The X-ray diffraction (XRD) and The Fourier transform infrared spectroscopy (FTIR) confirmed the formation spinel structure. The obtained crystallite sizes ranged between 9.33 and 22.89 nm, while lattice parameters increased from 8.285 to 8.462 Å depending on the...
Metal oxides are very popular because of their irreplaceable properties. In recent times, these metal oxides are used in several areas and particularly a number of research activities have been undertaken to explore rare-earth metal oxides. A series of rare-earth-based compounds are extensively used in several grounds of current science and technology as a result of their unusual optical,...
Biogas, as a renewable energy source, has gained attention due to its potential to reduce greenhouse gas emissions and provide sustainable alternatives to fossil fuels. However, its widespread adoption is hindered by challenges such as low methane (CH4) content and corrosive impurities such as hydrogen sulphide (H2S), which limit its efficiency and application. This...
Rare-earth (RE) ions enhance the stability of permanent magnets against demagnetization, making them vital in wind turbines, electric vehicle engines, magnetic resonance imaging machines, and cell phone devices. However, the rising costs and dwindling reserves of RE materials necessitate the development of RE-free permanent magnets for a sustainable economy. This study uses first-principles...
Abstract
Lithium transition-metal oxides, such as LiM2O2 and LiMO2 (where M = Ni, Mn, Co, etc.), are commonly used as cathode materials in lithium-ion batteries. These materials offer good capacity, low cost, high thermal stability, and energy density. However, they suffer from Jahn-Teller distortion, which leads to structural instability and decreased performance. One way to improve these...
Organic-inorganic perovskite solar cells suffer from low stability and the solution methods used for fabrication are not always scalable or reproducible. Perovskite solar cells with inorganic absorber layers and charge transport layers are an attractive route towards achieving long-term stability. Additionally, resistive evaporation allows for scalable and reproducible thin films. The...
We view electrochemical impedance spectroscopy as a specialized case that characterizes an electrochemical system by measuring its alternating current or potential signals. The measurements are normally used to identify the physical phenomena that control electrochemical reactions in the system and to determine the corresponding physical properties. It does provide an indirect means to measure...
Entangled quantum states find themselves in many active fields, such as cryptography and information transfer. High dimensional states are highly sought after as they can carry large amounts of information. One method used to scale the amount of information carried by these states is to use higher dimensional degrees of freedom (DOFs). However, these states are fragile, easily disturbed by...
The rapid advancement of high-performance computing and spintronic technologies demands the development of novel materials that combine high magnetic anisotropy, thermal stability, and mechanical robustness. L1₀ ordered MnPt is a promising rare-earth-free candidate due to its large magnetocrystalline anisotropy and strong spin polarization. However, its practical application is hindered by...
Gamma-ray spectrometry remains a cornerstone technique in nuclear science and environmental radioactivity assessment, offering precise identification and quantification of radionuclides. Despite its efficacy, conventional analytical methods often rely on manual processing, which can introduce subjectivity, reduce throughput, and hinder real-time analysis. In this study, an automated framework...
The global shift towards sustainable energy highlights the importance of supplying electricity to rural regions through renewable energy microgrids. Community development centres, such as the Masia Development Centre in Limpopo, South Africa, play a crucial role in community development and local economic growth. However, they often face challenges related to unreliable or insufficient power...
Structured light, owing to its ability to carry orbital angular momentum (OAM) as an additional degree of freedom for information encoding, has attracted significant attention in optical communication and information processing. However, in practical applications, the helical phase structure of structured light is inevitably distorted by turbulence effects during propagation through complex...
Equilibrium and elastic properties of hexagonal molybdenum disulphide (MoS2) are investigated using the full-potential all electrons linearised augmented plane wave method. Generalized gradient approximation of Perdew-Burke-Ernzerhof for solids (GGA_PBE_Sol) was chosen to calculate equilibrium electronic structure and elastic properties. Electronic band structure and density of states results...
Anode materials used in lithium-ion batteries have gained enormous interest in research due to their high Coulombic efficiency and cost-effectiveness. Commercially, graphite is used as the anode material due to its stability but exhibits a low capacity of 372 mAh/g (LiC6). Silicon has attracted attention because of its high theoretical capacity of 4200 mAh/g (in Li4.4Si), making it a promising...
Doped transition metal nanoclusters have gained significant interest for essential scientific research and various application purposes in catalysts, electronic and biomedicine. Elemental alloying of nanoclusters is considered as an efficient way to improve their stability, electronic properties, and reactivity. However, few studies comprehensively evaluating the effects of alloying Os and Ru...
Titanium Nickel (TiNi) alloys are widely used in biomedical and aerospace applications due to their unique shape memory effect and superelastic properties. However, their susceptibility to corrosion in aggressive environments limits their long-term performance and reliability. Understanding the surface stability of TiNi is crucial for developing strategies to enhance corrosion resistance and...
Sphalerite (ZnS), pyrite (FeS2), and galena (PbS) are found in association with each other in the mineral’s ore deposits. The separation of these minerals is critical and these require fundamental understanding from the surface properties. The study investigated the behaviour of the surface properties of these minerals at room temperature (300 K) utilizing the ab-initio molecular...
Fe-Cr-based alloys are ideal for fusion reactor structural components because of their reduced activation and swelling, corrosion resistance, and excellent hardening or embrittlement properties in various radiation environments. However, Fe-Cr alloys have high hydrogen uptake capacity, and enhance hydrogen embrittlement can cause material degradation and premature failure, necessitating an...
Abstract
The transition metal dichalcogenide (TMD) NaVS₂ has attracted considerable attention as a candidate for energy storage systems, particularly sodium-ion batteries (SIBs), owing to its excellent electrical conductivity, advantageous electronic properties, and catalytic versatility. Nevertheless, its practical application is hindered by limited ionic conductivity and suboptimal cycling...
EuTiO₃ and TbMnO₃ are perovskite rare-earth-transition metal-based oxides hosting multiple ferroic order states (multiferroics). Ferroic ordering refers to the spontaneous alignment of ferroic orders due to an applied stimulus, like magnetic or electric fields. The three primary ferroic orders are ferromagnetism (spontaneous spin ordering), ferroelectricity (spontaneous charge ordering), and...
We are inspired to study the K2SbAu ternary compound using first-principles methods based on density functional theory (DFT) to advance the optoelectronic technology. This comprehensive study predicts structural, electronic, elastic, mechanical, and optical properties. The lattice parameters of the K2SbAu ternary compound were in agreement with the experimentally observed...
The growing global energy crisis necessitates the search for sustainable and environmentally friendly alternatives to fossil fuels. In this study, first-principles Density Functional Theory (DFT) calculations were employed to investigate the structural, electronic, optical, and mechanical properties of the all-inorganic perovskite compound CsPbI₃, a promising material for clean energy...
Tungsten (w) is considered as the potential plasma facing material for fusion reactor application due to its exceptional mechanical and thermal properties. The notable properties of tungsten are its high melting point, high thermal conductivity, hardness, and low sputtering yield. However, tungsten also presents a very low fracture toughness limiting its application as plasma coating material....
The threats posed by climate change have been reported to be driven by use of fossil fuels. Therefore, to effectively mitigate these challenges, there is need of transitioning to renewable energy sources such as solar and wind. A critical component of this transition is developing energy storage devices that not only match but exceed the energy and power densities of fossil fuels. Batteries...
Abstract:
Solid-state electrolytes face critical challenges in achieving sufficient ionic conductivity and structural stability for practical battery applications. NASICON-type LiTi₂(PO₄)₃ (LTP) offers a promising framework due to its 3D ion diffusion channels and thermal stability, but its bulk conductivity remains limited by restricted Li⁺ migration pathways. Anion doping presents a...
Titanium-based shape memory alloys (SMAs) are valuable for biomedical applications due to their mechanical stability and biocompatibility. However, their clinical performance is limited by ion release, stress shielding effects due to bone-implant stiffness mismatch, toxicity risks, and the need for optimized phase stability. This study aims to improve the Ti-Ni-Mo alloy's performance by...
Nickel-rich layered metal oxides, such as LiNiO₂, are among the most promising cathode materials for next-generation lithium-ion batteries due to their high energy density. Doping is widely recognized as an effective strategy to enhance their structural stability and electrochemical performance. However, a detailed understanding of the role played by individual dopants is essential for...
Polyanionic phosphate-based materials have gained significant interest as cathode materials for sodium-ion batteries (SIBs) owing to their intrinsic thermal stability, structural integrity, and elevated operating voltage. This study employed first-principles density functional theory (DFT) computations with the generalized gradient approximation (GGA + U) in Materials Studio, applying an...
Nickel-rich layered materials such as LiNiO₂ offer high energy density, making them strong candidates for next-generation lithium-ion battery cathodes. However, their structural instability remains a critical challenge. In this study, spin-polarized density functional theory calculations [DFT + U-D3 (BJ)] were employed to investigate the effects of Nb and Mn doping on the first and second...
The development of sodium-ion battery (SIB) technology relies on the development of high-performance cathode materials. Ithis study investigates the structural, electrical, and electrochemical properties of Ni-doped NaMnPO3F cathodes (NaMn1-xNixPO3F, 0 < x < 0.5) through the first-principles calculations based on density functional theory (DFT). The simulations conductedin this study show a...
\begin{abstract}
Half-Heusler alloys such as ZrCoSb, ZrCoBi, and ZrCoAs are promising thermoelectric materials for recovering waste heat because of their favorable electronic and thermal properties\cite{reference1,reference2}. However, achieving low-resistance electrical contact at the hot interface between half-Heusler materials and metal electrodes remains a significant challenge. Recent...
Ongoing research on lithium-air batteries aims to overcome setbacks caused by shuttle effects by exploring various cathode materials, with a particular focus on 2D materials such as monolayer boron oxides (MBOs).These materials are gaining popularity due to their unique properties, such as large surface areas, ballistic electronic transport, mechanical strength, and anisotropy, making them...
Understanding the impact of radiation on detector components is essential for ensuring the sustained long-term performance of the ATLAS TileCal, particularly in the high-luminosity phase of the LHC. This study details a variety of FLUKA Monte Carlo simulations investigating the effects
of gamma irradiation on selected materials used in the dynode chain of photomultiplier tubes, a vital...
This paper develops a decision-making algorithm using the fuzzy set theory in assessing the physico-chemical properties and microbial contaminants of boreholes located in villages around the North-West Province, where Magalies Water, a water board in the Republic of South Africa centrally operates.
Application of fuzzy rule-based optimization technique will be illustrated with 42 groundwater...
The cobalt tungstate (CoWO4) nanostructures were prepared using the hydrothermal method. Nanostructures were annealed to compare the structural, optical and gas sensing properties of annealed and unannealed CoWO4. The UV-VIS spectroscopy, x-ray diffraction (XRD), scanning electron micro-scope (SEM) and energy dispersive x-ray spectroscopy (EDS) were used to examine the samples opti-cal,...
The ghost imaging protocol captures the phase details of transparent objects and encodes them into the amplitude of the reconstructed image, all through joint projective measurements between two entangled photons. Similarly, Grover’s algorithm amplifies the inverted amplitude of a marked element, isolating it from a larger dataset through quantum interference. Despite their different origins,...
Abstract:
Apatite coatings formed on metallic substrates such as Ti-6Al-4V (Ti64) can promote osseointegration and are of significant interest for orthopaedic and dental implant applications. However, the slow formation of apatite layers in conventional simulated body fluid (SBF). In this study, we investigate the growth kinetics of apatite layers formed on Ti64 substrates using an enhanced...
We performed water adsorptions on the PtSb2 (100) surface, where H2O was adsorbed through oxygen on top of the surface Pt and Sb atoms. The (100) surface was explored by increasing the number of H2O on the surface. The (100) surface was explored by increasing the number of H2O on the surface. Lastly, the full-surface coverage (16/16 H2O/Sb, Pt) was investigated where all Pt and Sb were...
Lagenaria Siceraria Cucurbitaceae , a biomass commonly known as calabash, is utilized in African rural communities as a transport means for fluid often water of traditional beverages and for food conservation in African rural communities. Material Heat Transfer for Food Conservation. Python coding was employed to study heat transfer process in the event hot or warm pap commonly eaten as the...
This work explores the Hilbert's Hotel paradox, a thought experiment illustrating the counter-intuitive nature of infinity, and its modern optical analogy. Historically, infinity was a vague concept until Georg Cantor provided a mathematical foundation. The paradox describes an infinitely occupied hotel that can always accommodate new guests by shifting existing ones. Recent research has...
The utilisation of mode division multiplexing, where multiple spatial modes transmit data simultaneously, holds significant promise for enhancing bandwidth in free space optical communication systems. However, atmospheric turbulence can compromise the reliability of these systems. To address this longstanding problem, traditional neural networks have been employed to classify modes in...
ZnO-TiO2:Yb3+/Ho3+ phosphor heterostructures were successfully synthesized by the hydrothermal process. The structure, morphology and upconversion (UC) luminescence properties of the prepared heterostructures were investigated. The mixed oxides of ZnO and TiO2 anatase and rutile were confirmed by X-ray diffraction (XRD). Scanning electron microscopy (SEM) revealed the agglomerated and...
In this study, we combine simulation and topological analysis techniques to identify and study cosmic filaments. We employ the Simba-C simulation, a large-volume hydrodynamic cosmological simulation that incorporates dark matter, baryonic matter, and chemical enrichment, to produce a representative slice of the Universe. To detect filamentary structures within this simulated data, we utilize...
Li2MnO3, a promising cathode material for high-performance energy storage, was synthesized in nanosphere, nanoporous, and bulk morphologies using the amorphization and recrystallization technique. The influence of morphology on the structural evolution and electrochemical behavior of Li2MnO3 was investigated focusing on its impact on lithium-ion...
The production of high-quality radioisotopes is essential for nuclear medicine, scientific research and various industries. These radioisotopes are produced using advanced particle accelerators at iThemba LABS and have become the leading organization for radioisotope production. The process requires precise control over the beam parameters, the target material, and the chemical processing....
The production of high-quality radioisotopes is essential for nuclear medicine, scientific research and various industries. These radioisotopes are produced using advanced particle accelerators at iThemba LABS and have become the leading organization for radioisotope production. The process requires precise control over the beam parameters, the target material, and the chemical processing....
The rapid evolution of electrochemical energy storage and the growing environmental concerns demands advanced materials. MXenes, particularly Ti3C2 have been targeted to meet these demands due to their exceptional conductivity, layered structure, and tunable surface terminations. Generally, MXenes acquire surface terminations such as -OH, -O, -Cl, and -F after the etching process, which can be...
The outstanding energy density and capacity exhibited by lithium-rich manganese-based layered oxide (LRLO) cathode materials have positioned them as emerging strong contenders for future lithium-ion battery systems. Their optimal utilisation is hindered by several challenges, such as Mn-migration and oxygen loss, contributing to structural reconstruction resulting in voltage fading and poor...
Calcium, the fifth most abundant element in the Earth’s crust, has emerged as a promising alternative to lithium for next-generation rechargeable ion batteries due to its natural abundance, low cost, and favourable redox potential. However, identifying a suitable cathode material capable of accommodating the reversible insertion and extraction of Ca²⁺ ions without undergoing significant...
Abstract
The ongoing issue of community blackouts due to load reduction and shedding needs urgent solutions. These power interruptions disrupt daily life and affect supply and demand dynamics. The root of the problem is the high cost of electricity and annual tariff increases. As a result, some customers resort to illegal connections, theft, and meter tampering to reduce their...
Chalcopyrite is a major source of copper and its significance extends to a wide range of applications. Although chalcopyrite mineral recovery is achieved to some satisfactory, there is still a need to improve its recovery in particular the low grade and hard to float chalcopyrite. This requires a highly selective collector to target and float the desired mineral. The modification of collectors...
The study on performance of the novel 2,6-dithio-4-butylamino-1,3,5-triazine (DTBAT), normal butyl xanthate (NBX) and normal butyl dithiocarbamate (NBDTC) collector on platarsite serve as a foundation for understanding the flotation reactivity, which may be applicable in a wide range of sulphide and arsenide platinum group minerals (PGMs). This study adopted computational density functional...
Abstract
The currently available machine learned force-field (MLFF) within ab-initio molecular dynamics (AIMD) embedded with the Vienna ab-initio simulation package (VASP), allows for generation of force field to handle large systems. The AIMD-MLFF methods were employed in the current study to investigate the bulk and surface properties of sperrylite (PtAs2), geversite (PtSb2) and insizwaite...
Zinc aluminate (ZnAl2O4) is a member of the spinel family which has attracted great research interest due to its diverse properties such as high fluorescence efficiency, hydrophobicity, high chemical, and thermal stability. These properties make it a suitable candidate for application such as in displays, magnetic refrigerators, catalysis, and light emitting diodes (LED)....
This study explores the potential of an ABPBI–carbon nanotube composite as a candidate for space coating applications in Low Earth Orbit (LEO), using a combined computational and experimental approach. The goal is to assess how the composite's structural, electronic and optical properties respond to the demanding conditions of the space environment.
Density functional theory (DFT) as...
The hydrothermal method was used to synthesize the hematite phase in this study. To investigate the effect of doping with rare earth metal on the metal oxide semiconductor (MOS) and also to explore the structural, morphology, and optical properties of the hematite phase, four samples with different doping percentages of the samarium (sm) were prepared (0%, 2%,4% and 6%). As-prepared samples...
Hydrogen generation is predicted to replace fossil fuels in the future due to its capacity to manufacture low-carbon hydrogen through electrolysis with renewable electricity. Storage remains a challenging issue that impacts safe end utilization of hydrogen as fuel as well as its distribution and delivery. Hydrogen storage criteria for solid-state fuel cell applications include high volumetric...
This study adopted the ab-initio molecular dynamics (AIMD) modelling technique imbed-ded within the Vienna ab-initio simulation package (VASP). The machine learned force field (MLFF) was utilized for robustness of the AIMD simulations. These methods were adopted unravel the bulk and surface stability of the platinum group minerals (PGMs) such as moncheite (PtTe2), merenskyte (PdTe2),...
Ionizing radiation, comprising high-energy particles and electromagnetic waves, is prevalent in medical physics, nuclear research, and reactor operations, posing significant biological risks. Effective shielding is critical to minimize radiation exposure, traditionally relying on dense materials like lead and concrete. Lead offers high atomic number advantages but is toxic, while concrete,...
As technology advances, ionizing radiation has become an essential tool in various fields such as medicine, industry, and research. However, excessive exposure poses serious health risks, including cancer. This study investigates the radiation shielding properties of heavy metal oxide (HMO) glasses to provide safer, lead-free alternatives for X-ray and gamma-ray protection. A series of glasses...
Over the past decade, photovoltaic water pumping system (PVWPS) concept failed to perform optimally due to its complexity of multiple systems that run together. Lack of access to real-time data caused poor system’s performance and ultimately ceased to supply the solar energy to pump the water. Therefore, a system to integrate and manage the multi-systems nexus of PV solar power output, water...
Collectively, conventional technologies for HIV-1 drug-resistant mutation detection have established the basis for understanding the mechanisms involved in drug-resistant mutations and have thus led to the development of antiretroviral therapy (ART) regimes that target and suppress drug-resistant variants. Technologies like Sanger sequencing, Next Generation Sequencing (NGS), and Polymerase...
Sensors based on Low Gain Avalanche Diode (LGAD) technology enable high precision timing and position measurements. Paired with a high radiation hardness as well as low production costs, LGAD sensors represent excellent candidates for in-beam detectors, such as beam structure monitoring, but also for various tracking applications. They are currently used for both ATLAS and CMS experiments for...
Be X-ray binaries (BeXBs) are a subclass of high-mass X-ray binaries consisting of a Be star and a compact object, typically a neutron star. The Be star features a Keplerian disc, known as a "decretion" disc, in its equatorial regions. This disc is thought to form due to the star's rapid rotation. The interaction between the decretion disc and the neutron star leads to the accretion of matter,...
In this work, we aim to compute the radio flux from the decay of axions close to Saggitarius A, the supermassive black hole at the center of our galaxy. These particles can undergo stimulated decay in the presence of photons with energies of half the axion mass. We make use of an observed spectrum for Sgr A emission in the frequency range of SKA and the VLBA, to find the effect of stimulated...
This study explores the impact of metal ions (Mg, Ca, Sr, and Ba) on the properties of Na3PO4. The resulting nanophosphors, NaMgPO4, NaCaPO4, NaSrPO4, and NaBaPO4, were synthesized using solid-state reaction techniques and doped with 1 mol% Ce3+. The synthesized nanophosphors were annealed at 900°C for 4 hours, except...
This study aims to apply a machine learning methodology to model and predict the magnetocaloric effect in perovskite oxides. A specialized machine learning approach was developed to predict the magnetic entropy change (ΔSM) of both double and single perovskite oxide materials using data extracted from the literature. A dataset comprising 1 727 entries was constructed using...
Our research is driven by the goal to realize ferromagnetism at room temperature on non-magnetic materials such as semiconductors, among other materials. If realized, semiconductor functionality should coexist with ferromagnetism, ideally above room temperature (practical operating temperatures). In our work, ZnO single crystals implanted with 45 keV 40Ar ions up to fluences of...
Structured light, which involves the precise manipulation of an optical fields the internal degrees of freedom, has emerged as a key tool in both quantum and classical information processing protocols. Its benefit in the realm of photonic computing lies in its ability for high-dimensional, light-speed information processing. In this work, the high dimensional nature of light is leveraged by...
The synthesis of methanol from syngas (CO/CO₂/H₂) via hydrogenation on the ZnO (010) surface supported by CuPd cluster has been studied using periodic density functional theory (DFT) calculations. Our findings indicate that direct hydrogenation of CO₂ to methanol is selective. In the presence of surface atomic hydrogen and oxygen, CO₂ tends to form highly stable formate (HCOO) and formyl...
In this work simulations of the interaction of a stellar wind with the interstellar medium, which forms an astrospheric cavity, are presented. Results are shown where the astrosphere of Lambda Cephei is simulated for three different scenarios, corresponding to three different ISM speeds. The results can be visualized as density contour plots as well as radial profiles for different simulation...
From the rich soil of Tshivhase tea estate in Thohoyandou, blooms the green fields of Midi tea plantation and processing units. This delicious and locally produced black tea is largely available locally and open for market anywhere in the world. The increase in demand for storage devices prompted researchers to consider other possible, low cost and commercially viable alternatives to meet the...
This study examines the contribution of hybrid energy systems to achieving carbon neutrality in South Africa's power sector by integrating solar, wind, and hydroelectric resources. Employing the IRENA FlexTool, the study examines various hybrid system configurations to evaluate their efficiency in reducing reliance on fossil fuels while ensuring grid stability. This study investigates the...
The reduction of titanium tetrachloride (TiCl4) with magnesium (Mg) results in the production of intermediates such as titanium trichloride (TiCl3) and titanium dichloride (TiCl2). Experimental work has been done to develop a continuous reduction process using TiCl3 and TiCl2. However, more investigations still need to be done to understand these mediums and their interactions. In this study,...
The phenomenon of multiple ionization induced by heavy ion impact plays a significant role in altering the atomic structure during inner-shell ionization processes. In this work, we investigate the degree of multiple ionization in the outer shells (M, N, etc.) accompanying L-shell ionization of Bi, Gd, and Y targets bombarded by carbon ions with incident energies ranging from 0.33–1.0 MeV/u....
The ATLAS inner tracker (ITK) proposed for the upgrade is divided into the strips, outer pixels and inner pixels, each with its own complexities and inbuilt systems. The outer pixel is sandwiched between the strips and the inner pixel. It is flushed with N₂ from the inlet to the outlet to maintain the dryness of the outer pixels. However, specific temperature, humidity and dew point...
Structured light, where complex optical fields are engineered across all degrees of freedom, has recently become a highly topical area of research. This rise is fueled by the development of sophisticated toolkits for the creation, control, and detection of light. Traditionally, both the creation and detection of structured light have assumed a fixed wavelength, relying on linear superpositions...
ABSTRACT
Neonatal jaundice, also known as neonatal hyperbilirubinemia, is a common condition among newborns in the first week after birth. Notable, it is a leading cause of death and disability for newborns in low-resource nations, including Southern Africa nations. Persistent challenges due to inadequate, inefficient or financially inaccessible diagnostic alternatives for its management in...
Nuclear Forensic Science (NFS) plays a crucial role in enhancing nuclear security, primarily through the detection and attribution of illicit nuclear materials. However, its application in nuclear waste management remains underexplored. Inadequate disposal and poor tracking of nuclear waste pose significant environmental and public health risks, especially in regions with limited regulatory...
Two-dimensional (2D) metal halide perovskite (MHP) thin films were synthesised by the conversion of lead halide thin films to 2D MHP thin films using a two-step low-pressure chemical vapour deposition (LPCVD) method. The first step involved the deposition of lead halide thin films (i.e., PbI2, PbBr0.6I1.4, PbBr1.1I0.9,...
In the current study, we are exploring the Li-rich cathode material Li2MnO3 which is generally electrochemically passive. Li2MnO3, as a Li-ion and structural stabilizer, can offer higher capacity and is thought to be a promising alternative to traditional cathode materials, such as LiCoO2, in the form of Li-rich Mn-based layer-structured oxides, xLi2MnO3-(1-x)LiMO2 (M = Ni, Co, Mn, etc.). we...
Dye-sensitized solar cells (DSSCs) are photovoltaic devices that provide high solar to electric energy conversion efficiency through light sensitization of metal oxides by adsorbed dyes. Recently, considerable research has focused on enhancing the efficiency of DSSCs by improving individual elements of the device. Among all the elements, porous TiO2 thin-films sensitized with light-absorbing...
South Africa, with abundant renewable energy resources, is undergoing a significant transition as it strives to integrate renewable energy into its energy mix to meet the country’s growing demands sustainably. However, the efficient utilization and integration of renewable energy sources into the grid poses several technical, economic, and regulatory challenges. This research proposes a...
The growing demand for electricity in off-grid regions, combined with rising global energy needs driven by population growth, underscores the urgent need to explore renewable energy alternatives to fossil fuels key contributors to carbon emissions and climate change. Wind energy offers a sustainable option but is challenged by its variability and low-speed performance in certain regions. This...
This study investigates the extraction methods of chlorophyll extracted from green algae to be used a natural photosensitizer in dye-sensitized solar cells (DSSCs). Three extraction meth-ods were employed: solvent-assisted extraction (SAE), ultrasonic-assisted extraction (UAE), and microwave-assisted extraction (MAE). Chlorophyll was then characterized for its optical, morphological, and...
As South Africa grapples with ongoing energy shortages and rising demand, hybrid renewable energy microgrids have emerged as an effective and scalable approach for supplying power to off-grid and rural communities. This study, which explores the performance of a hybrid microgrid that integrates photovoltaic (PV) panels, fuel cells, and battery storage systems, plays a crucial role in providing...
Getting affordable and clean energy is the 7th UN Sustainable development goal. One way of achieving this goal is to ensure that renewable energy sources like solar, wind, and thermal energy are accessible at reasonable prices to everyone. Solar energy is recognized as an effective way to deal with environmental pollution and global warming and, most importantly, make electricity accessible to...
High-voltage spinel LiMn1.5Ni0.5O4 (LMNO) is a promising material for next-generation lithium batteries. It has attracted interest as a high-voltage cathode due to its theoretical operating potential of 4.7-4.8 V versus Li⁺/Li. However, its practical implementation faces substantial challenges from structural degradation and capacity fade during cycling, originating from complex phase...
Abstract: Reduced graphene oxide/gold nanoparticle (rGO/AuNP) nanocomposites emerge as versatile materials for sensing, and biomedical applications; however, their practical implementation is frequently hindered by poor colloidal stability and aggregation mainly attributed to the stripping of ligands by rGO, inadequate anchoring of AuNPs, and electrostatic disturbances. In this study, we...
Today, lithium ion batteries (LIBs) dominate the rechargeable battery market despite their limitations, including low energy storage density (100–200 Wh/kg), high cost, potential supply shortages, and safety risks due to the flammability of lithium and organic electrolytes. Metal-air batteries (MABs) offer a high energy density, ranging from 400 to 1700 Wh/kg. However, the Fe-air battery (764...
There is a growing need for safer homes, environments, and industries; this can be achieved by having gas sensors that are more efficient, cost-effective, and have low power consumption. However, currently used materials for gas sensing have limitations, calling for a need to search for materials with optimal and desired gas-sensing properties. Traditional methods, such as density functional...
The global shift towards sustainable energy highlights rural electrification via renewable energy microgrids. In South Africa, agricultural development centres are crucial for ensuring food security and fostering rural economic growth, yet they frequently struggle with unreliable electricity access. Understanding the energy consumption patterns of these facilities is essential for effective...
The study aims to presents the results of a probabilistic risk assessment that was conducted to replicate the MACCS code model and data analysis typical of the South African Nuclear Power Plant (NPP) environment. This was done to determine the potential atmospheric release and consequence of radioactive material for postulated severe accident case based on current NPP configuration. This work...
To mitigate challenges of climate change, transitioning from fossil fuels to renewable energy sources is crucial. At the center of this shift is the energy storage systems, particularly batteries with energy densities exceeding that of fossil fuels. Since an electrode of a battery determine the energy density, 2D materials like beta-12 borophene have emerged as exceptional electrode due to...
An open challenge in quantum information processing and communication is enhancing the robustness of quantum information against environmental noise, a major obstacle in real-world applications. In this work, we study the decay of quantum states under generic noise, as measured by the decline of conventional entanglement witnesses, typically used as resources for quantum information encoding....
Lung cancer has highest mortality rate of all cancers worldwide and this is due to late detection of the disease. Current diagnostic techniques are invasive and expensive resulting in late diagnosis. Exhaled human breath offers an alternative rapid and non-invasive technique. This is because human breath has volatile organic compounds (VOCs) some which can be biomarkers of certain diseases....
The Phase-II upgrades focus on enhancing the Tile Calorimeter's capabilities in ATLAS detectors, essential for high-energy physics research. Led by Wits University, these upgrades involve improving LVPS bricks, which convert 200V DC to 10V DC for detector operations, ensuring radiation resistance and reliability. Over a thousand LVPS bricks will be produced, each undergoing initial and final...
Real-time monitoring and control are essential in particle physics environments, where experimental precision depends not only on instrumentation stability but also on the well-being of personnel. Technicians and physicists at CERN often work long hours on sensitive detector systems within confined spaces, where elevated CO₂ levels can impair cognitive function and reduce operational...
Variable stars are stars whose brightness varies with time when observed from Earth. The change in brightness may
be due to changes in star’s luminosity, and obstructions in the amount of light that reaches Earth. Studying variable
stars helps understand stellar evolution and properties. The project aims to search for and classify variable stars using
photometric time-series data from the...
It is known that light is an electromagnetic wave and hence, has an intensity and phase profile. In the real world, these properties are distorted by turbulence when light is allowed to propagate through an atmosphere – which it must do for many real-world applications. The need to utilize light in the real world has hence prompted significant studies of atmospheric turbulence. Generating...
N-type low-dimensional semiconducting oxides such as Ga2O3 and SnO2 have received significant interest in the detection of toxic gases due to their excellent opto-electronic response, thermal and chemical stability. However, key challenges such as high operating temperatures and poor selectivity continue to impede their practical usage. In this study, pure...
We present an efficient method to generate spatially resolved longitudinal spin angular momentum (LSAM) in optical tweezers using tightly focused first-order spirally polarized vector (SPV) beams with zero intrinsic angular momentum. When focused into a refractive index (RI) stratified medium, the beam forms spherically aberrated intensity patterns with off-axis lobes carrying LSAM of opposite...
The target star of this research, HD68695, has characteristics of a young star with its age estimated to be about 7.3 million years by Arun et al. 2019. Murphy et al. 2020 observed strong emission in H-β, concluding that HD 68695 did not appear to be a λ-Böotis star and therefore its membership in the class was uncertain. Furthermore, Murphy et al. 2020, and Medupe et al. (2019) using...
The time-of-flight elastic recoil detection analysis (TOF-ERDA) method is an ion beam analysis technique that can analyse light elements in a sample with high depth resolution. This method uses simultaneous measurements of recoil ion energy and time of flight to determine ion mass. TOF is used to compute the energy of recoil ions, resulting in higher energy resolution than standard Silicon...
In the pursuit of advanced energy storage systems with high energy and power densities, two-dimensional materials like zirconium disulfide (ZrS₂) are being investigated as potential anode candidates for alkali metal-ion batteries due to their exceptional properties. However, there is limited information regarding the application of ZrS₂ monolayers as electrode materials specifically in sodium...
The present study investigates the combined effects of ion implantation and swift heavy ion irradiation on the structural and electrical properties of polyethylene terephthalate (PET). Samples were first implanted with 150 keV Ag⁺-ions at fluences of 1 x 10^16, 5 x 10^16 and 1 x 10^17, then irradiated with 30 MeV Au⁷⁺ ions. Atomic force microscopy (AFM) images and optical micrographs reveal...
The structural and electronic properties of Cu2S and Cu2Se powder samples were investigated using X-Ray Powder Diffraction (XRD), UV-vis spectroscopy and Fourier transform infrared spectroscopy (FTIR) and Current-voltage (I-V) measurements. XRD was used to calculate the lattice constants and crystal size of both materials. The lattice parameters of Cu2S and Cu2Se were calculated were found to...
This study explores the structural and magnetic properties of Ni₀.₅M₀.₅Al₀.₁Fe₁.₉O₄ (M = Zn, Mn, Mg) spinel ferrites synthesized using a modified glycolothermal method tailored for enhanced control over particle sizes, crystallinity, and tuning of magnetic parameters. Additionally, the study aims to optimize magnetic hyperthermia parameters and leverage biodegradable elemental...
Double perovskite oxides (A2B′B′′O6) with A-site being Rare Earth, B′ and B′′ the magnetic ions at the six-coordinate B-sites have been studied in the search for materials with enhanced magnetoresistive properties and for spintronics applications. The Sm2MgRuO6 polycrystalline compound was synthesized by conventional high-temperature solid-state reaction under controlled temperature and time...
Titanium dioxide (TiO2) is a promising material for applications in photocatalysis and photo-electrochemical water splitting. However, very few studies have been reported on the properties of bulk, single crystalline material. As a consequence, there is a substantial lack of understanding of some of the basic fundamental properties of this important compound, including its accepted band gap...
Nanoparticles of magnesium ferrite (MgFe₂O₄) and rare earth (RE)(La, Sm)-doped magnesium ferrite (Mg(RE)₀.₂Fe₁.₈O₄) were synthesized via the hydrothermal method and annealed at 500°C, 700°C, and 900°C. X-ray diffractometry (XRD), Ultraviolet-Visible Spectroscopy (UV-Vis), High-Resolution Transmission Electron Microscopy (HRTEM), and Photoluminescence (PL) spectroscopy were utilised for...
ABO3 perovskite materials are gaining interest due to their applications in materials, electronics, and photovoltaics [1]. One type of ABO3 is ZnTiO3, this material is highly favored because of its outstanding mechanical, optical, and insulating properties [2, 3]. It has been applied in various applications such as paint pigments, sorbents, microwave dielectrics, catalysts, dielectric...
Lithium-ion batteries are extensively utilised in portable electronics and are increasingly employed in electric vehicles and stationary energy storage. To improve safety and energy density, solid-state electrolytes (SSEs) are being explored for their non-flammability and stability with lithium metal anodes. Among these, garnet-type Li7La3Zr2O12...
We study the role of Parton Distribution Functions (PDFs) in calculating cross sections of Drell-Yan processes in proton-proton collisions at $\sqrt{s} = 13.6$ TeV. The theoretical production cross-sections of W$^\pm$ and Z bosons are calculated via their muonic decay channel using POWHEG and PYTHIA8 event generators. The contributions from each parton's PDF are explicitly shown in the...
Often extracted from an ore with a grade ranging between 25 and 35%, phosphorus is an important element in fertilizers, medicines, selected chemical compounds, cleaning products, steels, animals’ food and sensor devices. In addition to the physical magnetic and chemical concentration methods, direct concentration by flotation of phosphorus bearing minerals is employed. With an emphasis on the...
A series of BaB8O13 phosphors doped with different concentrations of (2.0 mol.%) Gd3+ ions and 1.0 mol.% co-doped with Pr3+, Pb2+, and Ce3+ ions were synthesized by solid-state synthesis method. The X-ray powder diffraction (XRD) analysis confirmed the pristine crystalline structure and uniformity of the compounds, with an...
Abstract:
Glassy Carbon (GC) has gained attention as a potential substrate for bone-implant application owing to its excellent properties such as biocompatibility, chemical stability, and mechanical strength. Despite these benefits, tissue integration and cellular adherence are restricted by it’s inherently bio inert surface. To increase bioactivity and encourage osteointegration, protein...
Molecular dynamics (MD) simulation methods were used to study the surface properties of nickel (Ni) and silver (Ag) metals. Calculations were performed at room temperature with the help of DLPOLY computer code. The many-body Sutton-Chen potentials were used to understand the interactions between atoms in both Ni and Ag surface systems. Stability patterns of three basic surfaces {(100), (110)...
The occurrence of negative magnetization (NM) refers to a switch from positive magnetization to negative values with the application of a positive probing magnetic field below the temperature having a magnetically ordered phase, which can rarely be caused by diamagnetism [1]. Such a novel phenomenon has created curiosity due to two states such as positive and negative magnetization as a...
In this study, titanium dioxide (TiO₂) nanoparticles were synthesized using the sol–gel method, setting the reaction time at 2, 4, and 6 h. The synthesized samples were then annealed at 500°C for 3 h. Structural, morphological, compositional, and optical characterization was carried out using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy...
Lead halide perovskites have shown great promise as solar absorbers for next-generation photovoltaics, but their toxicity poses significant challenges for practical use. As a result, considerable research has focused on developing environmentally friendly, lead-free alternatives with similar optoelectronic properties, including perovskites based on Sn, Ge, Mo and Bi. In this study, the...
The Technology Innovation Platform (TIP) at iThemba LABS, South Africa's national facility for accelerator-based sciences, aims to transform our nuclear and particle physics research into practical applications. We've set up TIP around several key technology projects in detector systems, data acquisition, specialised fabrication, and control interfaces. The work will include thick GEM...
ABSTRACT:
The transforming growth factor-beta (TGF-β) pathway is a pivotal regulator in directing adipose-derived stem cells (ADSCs) toward tenogenic lineage, making it a vital focus in tendon tissue engineering. Concurrently, photobiomodulation (PBM) has gained attention as a non-invasive technique to influence cell behavior and support tissue repair. Its potential to interact with...
Vectorial structured light has demonstrated numerous advantages of scalar light fields in various contexts, including communications, imaging and sensing. Their analogous mathematical structure to entangled biphoton states has allowed for the investigation of new physics in a more accessible manner. Recent work, inspired by the quantum metric commonly called the concurrence, has shown that the...
Localized surface plasmon resonance (LSPR) phenomenon occurs when incident light of specific wavelength excites the free electrons on the gold nanoparticles surface, which then leads to the enhancement of the nanoparticle surface electromagnetic field. The enhanced electromagnetic field has a short decay length and is localized in LSPR as opposed to the surface plasmon resonance (SPR) where...
Atmospheric monitoring systems play a crucial role in tracking weather conditions and assessing air quality, which is essential for both climate research and public health. While ground-based monitoring systems provide valuable localized data, they are limited in their ability to capture measurements at higher altitudes. Balloon-borne systems offer a solution to this gap, enabling the...
The NASICON-type LiTi₂(PO₄)₃ solid electrolyte is amongst the most promising electrolytes for solid-state batteries due to its broad electrochemical stability window and strong chemical durability. However, its relatively low ionic conductivity remains a major limitation for practical applications, hindering further development of LiTi₂(PO₄)₃-based technologies. Studies have shown that...
Neodymium-based permanent magnets (Nd2Fe14B) can be used in various applications, such as electric vehicles and wind power generators, due to their high magnetic field strength and demagnetisation resistance. However, they suffer from low operating temperatures below 585 K and poor mechanical properties. This study investigates the effect of rare earth elements such as Gd and Ce on the...
L10-ordered FePt alloy is a promising material for high-density magnetic recording media due to its high magnetic anisotropy energy, density and coercivity. However, it was reported that this alloy faces challenges including issues with thermal stability and noise. Hence, ternary alloying with Ir was conducted to enhance the stability in response to the orientation of the magnetic...
Research on the efficiency of physics practicals in enhancing student grasp of physics ideas is rare. This study looks into how physics practicals affect students' knowledge of physics concepts at the University of Limpopo. Students who had attended a physics course with a laboratory component were polled using a questionnaire. The results of this study indicate that physics practicals improve...
This research focuses on more than 15,000-millimetre wavelength sources observed using the Atacama Cosmology Telescope. These sources cover an area of approximately 18,000 square degrees and the ACT data observed at 98 GHz allows us to have a large population of AGNs at different redshift bands. This makes it possible to study the light these AGNs released at a redshift of up to 4.5,...
While Dark Matter (DM) is treated as a single substance in contemporary astrophysics research, the process whereby this DM paradigm has been established is a complex one, involving both theoretical contributions and astronomical observations. In defining this paradigm, we trace the growth in the number of citations since publication for a number of seminal papers. These include theoretical...
We investigate the evolution of the infrared–radio correlation (q$_{\rm IR}$) as a function of redshift (z) and stellar mass (M$_∗$ ) for star-forming galaxies (SFGs) in the COSMOS field, using MIGHTEE Early Science data. We use radio-detected galaxies with multi-wavelength counterparts to classify sources as radio-quiet AGN (RQ AGN), radio-loud AGN (RL AGN), and SFGs over the redshift range 0...
Young’s double slit experiment is often referenced when studying the concept of interference of light. To see an interference pattern in the intensity distribution, the two interfering beams must be coherent, that is they must have the same polarization. Polarisation describes the time variation of the electric field in the plane orthogonal to the plane of propagation of the beam. Polarisation...
This study investigated the impact of solar proton events (SPE) on the upper atmosphere over South Africa during intense geomagnetic storms in May (Dst = -412 nT) and October 2024 (Dst = -333 nT). Utilizing the NRLMSISE-2.0 atmospheric model and SOHO data, we characterized storm-time atmospheric composition and energetic particle fluxes. Significant fluctuations in atmospheric constituents...
The migration of silver (Ag) and strontium (Sr) ions co-implanted into polycrystalline silicon carbide (SiC) in the presence of helium (He) was studied using Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), Rutherford backscattering spectrometry (RBS), and transmission electron microscopy (TEM). 360 keV Ag ions were first implanted into SiC, followed by...
Tin (IV) oxide (SnO2) is a promising metal oxide (MO) semiconductor with potential in perovskite solar cells (PSCs) as an electron transport layer (ETL). The development of an additive-free SnO2 thin film with enriched optical properties using a cost-effective method is still a challenge. Herein, we report the influence of Ultraviolet ozone (UVO) on the additive-free hydrothermal synthesis of...
University of Johannesburg contributes 25% to the final design of the Tile Pre-Processor Modules for the ATLAS Tile Calorimeter at the High-Luminosity Large Hadron Collider (HL-LHC). This work focuses on the status of the Tile Computer-on-Module (TileCoM) and the Tile Gigabit Ethernet Switch (Tile GbE) in terms of firmware, software and hardware integration. The procurement of 62 Xilinx FPGAs...
The demand for batteries with higher energy density and storage capacity has been increasing over the past three decades. As such, spinel LiMn2O4 has emerged as one of the most promising cathode materials for Li-ion batteries, owing to its environmental friendliness, inexpensiveness, and structural stability compared to its counterparts, such as LiCoO2. However, LiMn2O4 suffers from high...
The integration of computer-based experiments (CBEs) in physics education has transformed traditional teaching methodologies by providing interactive, data-driven, and real-time analysis capabilities. This paper examines the role of CBEs in enhancing conceptual understanding, fostering inquiry-based learning, and improving student engagement. By utilizing digital simulations, virtual...
Mooihoekite (Cu9Fe9S16) is a copper-iron sulfide mineral belonging to the chalcopyrite derivative family, characterized by its metal-enriched composition. It crystallizes in the tetragonal system and is commonly found in association with minerals such as haycockite, magnetite, pentlandite, mackinawite, and sphalerite. Despite its structural similarity to the...
Abstract
The stimulated luminescence features of aluminum oxide (Al2O3) regulated by defects and impurities within the structure are well-known. Examples of resultant applied materials include Al2O3:C and Al2O3:C,Mg. This study examines the basis for the experimental observation that doping Al2O3 with Mg and C improves its thermoluminescence (TL) sensitivity. In order to study the...
Polycrystalline samples of PrOsGa4 and GdOsGa4 were prepared by arc-melting technique using high-purity elemental constituent elements. They were melted on a water-cooled copper plate under ultra-high pure argon atmosphere. The Rietveld crystal structure refinement of powder X-ray diffraction patterns with a full-profile refinement confirms that both samples crystallize in the hexagonal...
Organic polymers with inorganic reinforced composites are in daily use both domestically and industrially - in coating, adhesives, primers, aeronautic utilities, electro-optical devices and sensors, among others. These polymer-based materials are competing with metallic alloys in terms of cost and functionality (durability, strength, and other physical and chemical properties). However, the...
The High-Luminosity Large Hadron Collider (HL-LHC) necessitates a comprehensive electronics upgrade of the ATLAS Tile Calorimeter (TileCal) to ensure robust operation under increased radiation and data-rate conditions. To address this, the ATLAS TileCal has introduced the Phase-II upgrade, which involves a complete replacement of the existing electronic system. As part of the Phase-II upgrade,...
This research focuses on the design and development of high-resolution Time-to-Digital Converters (TDCs) and explores key parameters for evaluating their performance. Among various time-to-digital conversion methods, three approaches are examined in detail: counter-based, delay line-based (including Vernier, buffer, and inverter-based delay lines). The study specifically investigates the...
Accurate track matching is vital for reconstructing particle trajectories
in high-energy physics. In ALICE at the LHC, the upgraded muon tracking
system combines data from the Muon Spectrometer with the new Muon
Forward Tracker (MFT), a highly segmented silicon pixel detector positioned
near the interaction point before the hadron absorber. With the
MFT recording orders of magnitude more...
Graphdiyne, a carbon allotrope characterized by its unique two-dimensional structure, semiconducting behavior, and rich sp-hybridized carbon content, shows great promise for practical applications in fields such as energy storage, catalysis, and gas separation. Understanding the electronic properties of graphdiyne under tensile and compressive deformation is essential for its integration into...
Cosmological models in which dark matter and dark energy interact in a non-gravitational manner are known as Interacting Dark Energy (IDE) models and have been proposed to address many long-standing shortcomings and tensions in standard cosmology. Furthermore, recent results from the DESI Collaboration have suggested hints of dynamical dark energy, for which IDE models could provide a viable...
Semiconductor metal oxides are widely recognized as effective materials for gas sensing due to their ability to detect gases at trace levels, high sensitivity, and low production cost. Among various strategies to enhance their performance, heterostructures combining n-type and p-type semiconductors have proven particularly effective. In this study, cobalt oxide (Co3O4)-doped zinc oxide (ZnO)...
Temperature is an essential parameter in our lives. This spans from low-temperature environments of natural processes, such as biological systems, to high-temperature environments of manufacturing devices. Thermographic luminescence materials are an essential medium for remote temperature measurements. Luminescence materials thermometry utilizes temperature-sensitive powders, usually of host...
In Radio Astronomy there are several steps to follow to calibrate the data before it can be used for scientific research. One of these steps, specifically for a single-dish telescope like the Hartebeesthoek 26m telescope, is to do pointing observations to determine if the pointing model of the telescope is working properly. The pointing observations consists of pointing the telescope at the...
The search for new physics is one of the key goals of the ATLAS Collaboration. With the discovery of the Higgs boson in 2012, the Standard Model (SM) gained an essential ingredient towards the understanding of fundamental particles and their interactions – but it cannot yet be considered complete. The nature of Dark Matter (DM), which constitutes about 27% of the Universe, remains a major open...
Rural regions are largely reliant on non-renewable energy sources and frequently experience energy shortages. Alternative renewable energy sources like wind energy must be investigated to lessen dependency on fossil fuels and advance sustainability in these areas. This study evaluates wind energy potential in nearby locations by examining wind speed, direction, and flux data gathered using a...
A series of ZnMn2O4 samples partially doped with 1.0 wt% Co, Ni, and Cu were synthesized via combustion method and evaluated for improved electrochemical performance. The synthesized powders were thoroughly characterized using XRD, FE-SEM, FTIR, and electrochemical techniques (GCD, CV, and EIS) to evaluate their performance as anode materials for supercapacitor batteries....
