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Perceptions of Grade 10 to 12 adolescents on contextual situations that contribute to their psychosocial development challenges
Full text linkAdolescence is a complex developmental stage with challenges that affect transitioning to adulthood. The success in managing the transition depends on personal capabilities, circumstances, and support systems. Contextual situations in adolescent development are understudied in developing countries. In this qualitative study, we explored what South African Grade 10 to 12 adolescents perceived to be the factors influencing their experience of psychosocial challenges at home and at school. Participants (22 Grade 10–12 learners) completed an open-ended survey structured as a written interview. Thematic analysis of the data revealed 2 main themes: home life situations (household financial difficulties, unfavourable living conditions, time-inflexible house chores, poor parent-child relationships, lack of support from families), and school life situations (peers’ inappropriate behaviour, perceptions of ineffective school leadership, teachers’ low work enthusiasm and commitment, insufficient school resources, unsafe and unfavourable geographical conditions). The findings suggest a need for psychosocial intervention by school social workers at family and school levels to support adolescents in negotiating their psychosocial developmental transition to young adulthood. The departments of education, social development and health, the police services, and non-governmental organisations (NGOs) should collaborate to establish school programmes addressing learners’ disruptive behaviour and school safety concerns
Thermodynamic properties of deep eutectic solvents and organic solutes at different temperatures for separation of close boiling mixtures
Full text linkSubmitted in fulfilment of the requirements for the degree of Master of Applied Science in Chemistry, Durban University of Technology, Durban, South Africa, 2025.The environmental impact of volatile organic compounds coupled with its cost, stability,
performance, turnability and versatility of conventional solvents and its effectiveness
in the separation of close boiling point mixtures led to the growing interest in separation
studies of deep eutectic solvents (DESs). DES have advantages over conventional
solvents because of its distinctive properties such as thermal stability, easy and
inexpensive methods to synthesise, low toxicity levels and biodegradability. DESs are
recognized as possible alternatives to ionic liquids for diverse applications in the
chemical industry for example in product development. The understanding of physical
properties and intermolecular interactions is crucial for researchers and engineers to
design more efficient and environmentally friendly processes for the separation of
complex mixtures containing volatile organic solvents.
This study focuses on the thermophysical and thermodynamic properties of deep
eutectic solvents, categorized as type (III), for extraction or separation purposes.
Conventional organic solvents, which are currently utilized in industrial processes for
extraction or separation purposes are not environmentally friendly. The DESs were
synthesized at 1:3 mole ratio of hydrogen bond acceptor (HBA) and hydrogen bond
donor (HBD).
The classified type (III) deep eutectic solvents under this study were:
• DES1: 1-butyl-3-methylimidazolium chloride + ethylene glycol [BMIM]Cl: EG].
• DES2: 1-butyl-2,3-dimethylimidazolium chloride + ethylene glycol [BDMIM]Cl:
EG].
The physical properties namely: densities, , speed of sound, , and refractive indices,
, for the binary mixtures [BMIM]Cl: EG + methanol or ethanol, and [BDMIM]Cl: DEG
+ acetic acid or propanoic acid were experimentally measured over the entire range
of mole fraction, = (0-1) at = (293.15, 298.15, 303.15, 308.15, and 313.15) K
and at atmospheric pressure. The measurements were conducted using an Anton
Paar DSA 5000M and Anton Paar Abbermat 3200 refractometer. From the
experimental data, excess thermophysical properties including excess molar volumes,
vii
E
, isentropic compressibilities,
, change in isentropic compressibilities, ∆
,
intermolecular free length, , and change in refractive indices, ∆, were calculated
from the densities, speed of sound and refractive indices, respectively. The
investigated properties of the deep eutectic solvent binary mixtures gave an insight
into the types of molecular interactions in 1-butylmethylimidazolium chloride +
ethylene glycol with methanol or ethanol or 1-butyl-2,3-dimethyl imidazolium chloride
+ ethylene glycol with acetic acid or propanoic acid at different experimental
temperatures. The excess molar volumes, densities and refractive indices data was
correlated with the application of the Lorentz-Lorenz equation.
Density functional theory (DFT) was used to simulate the intermolecular interaction of
deep eutectic [BDMIM]Cl: EG] + acetic acid or propanoic acid as well as [BMIM]Cl:
EG] + methanol or ethanol binary mixtures. DFT calculations were employed to
ascertain some physiochemical descriptors such as chemical potential (),
electronegativity (), hardness (), the global electrophilicity index () and softness
().
The activity coefficients at infinite dilution (13
∞) of the selected deep eutectic solvents
with volatile organic solutes were also determined at different temperatures.
The deep eutectic solvents used for the determination of the 13
∞ were:
• DES3: Tetrabutylammonium acetate with ethylene glycol, [TBN]AcO: EG].
• DES4: Tetrabutylammonium acetate with diethylene glycol [TBN] AcO: DEG] .
The activity coefficients at infinite dilution was used as a pre-screening tool for the
selection of possible entrainers and was calculated from retention data obtained from
gas liquid chromatography (GLC) data. The GLC was operated at the temperature
range of = (313.15 – 353.15) K and at 10 K interval. Thermodynamic properties such
as excess enthalpies at infinite dilution, ∆1
E,∞, excess Gibbs free energies at infinite
dilution, ∆1
E,∞, and excess entropy at infinite dilution, ∆1
E,∞, were computed from the
activity coefficient at infinite dilution to further explain the types of intermolecular
interactions between the solutes and the investigated DESs. Selectivity at infinite dilution (
∞), and capacity at infinite dilution (
∞) values were determined to evaluate
the separation potential of the DESs.
The data obtained from the spectroscopic techniques Fourier transform infrared (FTIR
spectroscopy and nuclear magnetic resonance spectroscopy (NMR) were used to
validate the formation of DESs and the types of interactions arising between the HBD
and HBA. Furthermore, evaluation of thermal stability for the prepared deep eutectic
solvents was determined using differential scanning calorimetry (DSC)/
thermogravimetric analysis (TGA)
The role of the unemployment insurance fund in poverty alleviation in South Africa
Full text linkSubmitted in fulfilment of the requirements of the degree of Master of Management Sciences Specialising in Public Administration, Durban University of Technology, Durban, South Africa, 2025.This study examined the role of the Unemployment Insurance Fund in poverty
alleviation in South Africa, exploring its impact, challenges, and potential areas for
improvement. In the early 1940s, South Africa did not have an arranged or planned
social and economic system to support unemployed individuals. During the early 1946
regime, unemployed individuals suffered as there were few government interventions,
and charitable organisations were not persistent in helping them. The Unemployment
Insurance Act No.30 was introduced in 1946, and it was the first official and formal
legislation to help the unemployed in South Africa. The Unemployment Insurance Act
helped the unemployed financially, although it was a short-term relief. This is because
the Act aimed to help the unemployed temporarily while they were looking for another
job. Although the target and aim of UIF was to financially assist the unemployed in
South Africa, poverty as a socio-economic issue has remained a challenge in the
country. This is because poverty has impacted the quality of life for certain people and
has affected millions of citizens. This research aims to investigate and examine the
role of the Unemployment Insurance Fund (UIF) in alleviating poverty in South Africa.
The outcomes are expected to provide reliable and valid data on the effectiveness of
UIF as a measure to alleviate poverty in South Africa. The researcher used the
qualitative method as it has the advantage of producing clear data that can be easily
understood. The qualitative method was used to collect data on examining the impact
of the UIF payments on poverty alleviation upon job losses in South Africa, its extent
it fulfils its role in poverty alleviation, and to identify recommendations for the
implementation and disbursement of UIF payments towards poverty alleviation and
financial relief strains upon job losses in South Africa. The research findings can help
the government to design and implement more effective policies regarding
unemployment. The findings from the study helped with recommendations to reduce
poverty and assist the unemployed. The research findings provided intuitive
apprehension of the establishment of UIF in South Africa.
Unveiling the microbial symphony of amasi : a targeted metagenomic 16S rRNA, ITS, and metabolites insights using bovine and caprine milk
No full textAmasi, a traditional fermented milk produced in Southern Africa, is associated with several health benefits, such as probiotic activities, immune system modulation, and pharmacological (antimicrobial, antitumor and antioxidant) potential. This study investigated the microbial diversity in Amasi (produced from cow’s and goat’s milk) through targeted metagenomic bacterial 16S rRNA and fungal ITS sequencing, the metabolic functional prediction of Amasi samples using the Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) and profiled amino acids constituents using Liquid Chromatographic-Mass Spectrophotometry (LC-MS). The results obtained revealed Firmicutes, Bacteroidetes, and Proteobacteria as the most prevalent bacterial phyla, with Lactococcus and Lactobacillus being the most abundant genera. On the other hand, Ascomycota, Basidiomycota, and Mucoromycota were the main fungal phyla, while Aspergillus, Kazachstania, and Debaryomyces spp. dominated the fungal genera. Also, Pseudomonas spp., Bacillus spp., Clostridium spp., Cronobacter spp., Alternaria spp., Diaporthe spp., and Penicillium spp. were the probable pathogenic bacteria and fungi genera found, respectively. Atopobium, Synechococcus, and Parabacteroides were found less often as rare genera. It was found that the amino acid and drug metabolism pathway prediction values in Amasi samples were significantly higher (p < 0.05) than in raw cow and goat milk, according to the inferred analysis (PICRUSt). The amino acid validation revealed glutamine and asparagine values as the most significant (p < 0.05) for Amasi cow milk (ACM) and Amasi goat milk (AGM), respectively. Comparatively, ACM showed more microbial diversity than AGM, though there were relative similarities in their microbiome composition. PICRUSt analysis revealed significant metabolites in the two Amasi samples. Overall, data from this study showed heterogeneity in microbial diversity, abundance distributions, metabolites, and amino acid balance between raw cow/goat milk and Amasi samples.</jats:p
Resolving the puzzle of sound propagation in liquid helium at low temperatures
No full textExperimental data suggests that, at temperatures below 1 K, the pressure in liquid helium has a cubic dependence on density. Thus the speed of sound scales as a cubic root of pressure. Near a critical pressure point, this speed approaches zero whereby the critical pressure is negative, thus indicating a cavitation instability regime. We demonstrate that to explain this dependence, one has to view liquid helium as a mixture of three quantum Bose liquids: dilute (Gross–Pitaevskii-type) Bose–Einstein condensate, Ginzburg–Sobyanin-type fluid, and logarithmic superfluid. Therefore, the dynamics of such a mixture is described by a quantum wave equation, which contains not only the polynomial (Gross–Pitaevskii and Ginzburg–Sobyanin) nonlinearities with respect to a condensate wavefunction, but also a non-polynomial logarithmic nonlinearity. We derive an equation of state and speed of sound in our model, and show their agreement with the experiment
Temperature-driven dynamics of quantum liquids : logarithmic nonlinearity, phase structure and rising force
No full textWe study a large class of strongly interacting condensate-like materials, which can be characterized by a normalizable complex-valued function. A quantum wave equation with logarithmic nonlinearity is known to describe such systems, at least in a leading-order approximation, wherein the nonlinear coupling is related to temperature. This equation can be mapped onto the flow equations of an inviscid barotropic fluid with intrinsic surface tension and capillarity; the fluid is shown to have a nontrivial phase structure controlled by its temperature. It is demonstrated that in the case of a varying nonlinear coupling an additional force occurs, which is parallel to a gradient of the coupling. The model predicts that the temperature difference creates a direction in space in which quantum liquids can flow, even against the force of gravity. We also present arguments explaining why superfluids, be it superfluid components of liquified cold gases or Cooper pairs inside superconductors, can affect closely positioned acceleration-measuring devices
Consumer perceptions of critical success factors for small local consumer brands
No full textLocal or regional fast-moving consumer (FMCG) brands sold mostly in delimited geographic areas are a growing trend. This study aims to understand consumer attitudes towards such products and to identify factors critical to their success. The paper is a comparative study between developed (Germany) and emerging (South Africa) nations to identify differences between the preference criteria for FMCG. The methodology involved an online cross section survey in the two countries. Respondents from both countries preferred local brands and believe they are better quality and more supportive of, and connected to, local communities. South Africans feel this more strongly, show greater commitment, and are prepared to pay more than Germans. 'Beliefs' regarding quality, value for money, and trust in local brands are critical
Service quality of public technical vocational education and training colleges in South Africa : customer expectations and perceptions
No full textThe focus of this survey is to seek the amount of the customers’ expectations levels of service quality in the public Technical Vocational Education and Training (PTVET) sector. The aim of this study was to examine and determine the expectations and perceptions levels of service quality provided by PTVET colleges, in order to achieve desired outcomes, and the survey followed SERQUAL model. Questionnaires were distributed to the 403 participants from selected PTVET in the Kwa-Zulu- Natal province. The study used a mix approach of systematic and quota sampling techniques. SPSS (25.0) version was employed for data analysis. The results of this study discovered that customers had higher service quality expectations (0,908 Cronbach's Alpha) compared to the service quality perceptions (0,923 Cronbach's Alpha) at the selected PTVET colleges, on all five service quality dimensions that were used to evaluate the expectations of service quality. This survey will benefit Rectors/Campus Managers for TVET colleges and to those who want to open their TVET colleges, because it will be used as a guide tool for them on how they can improve service quality strategy to differentiate themselves from their competitors. The findings are limited by the study’s exploratory, quantitative nature and small sample. Generalisation should be done with care and further research, with a large sample and consideration of other provinces, it therefore recommended
Experimental investigation on the effect of gold tailings as a partial replacement for sand in concrete
No full textThis study explores the use of secondary gold tailings (SGTs) in concrete production to solve sand sustainability issues. This approach addresses waste issues and presents a sustainable material alternative to conventional sand, investigating different SGT proportions (ranging from 0% to 100%) to replace fine aggregate in structural concrete. This study examined the fresh, mechanical, and durability properties of concrete containing SGTs. Incorporating SGTs reduced the concrete’s workability, but up to a 75% replacement level resulted in a high fresh concrete density compared with the reference concrete. The results indicated that up to 25% replacement level increased the compressive strength and up to 50% replacement level improved the splitting tensile strength compared with reference concrete. However, all concretes containing SGTs exhibited satisfactory strengths. The statistical analysis confirmed the significant influence of SGTs on concrete strength. In addition, the durability results of the concrete demonstrated good resistance to oxygen, water, and chloride penetration, indicating good concrete quality. SGTs are recommended as a substitute for crusher sand to reduce production costs, conserve natural resources, and promote a sustainable and greener environment.</jats:p
Geopolymer cement in pavement applications : bridging sustainability and performance : an in-depth review
No full textGrowing concerns about the greenhouse effect, global warming, and adverse climate changes
primarily stemming from carbon dioxide (CO2) emissions in traditional Portland cement (OPC) used in civil
engineering construction, have prompted a shift toward eco-friendly alternatives like geopolymer cement
(GPC). Over the last few decades, significant advancements have been made in developing environmentally
sustainable pavement construction materials such as GPC to mitigate global CO2 emissions. The success of
geopolymer cement (GPC) as an eco-friendly alternative to OPC has garnered attention for its potential to lower
carbon emissions and enhance durability. This is attributed to the sustainable production method of GPC,
where industrial cementitious waste materials (such as fly ash (FA), metakaolin (MK), mine tailings (MT), slag,
etc.) are combined with an eco-friendly alkaline activator and water through the geopolymerization process.
Numerous studies on geopolymer concrete indicate that, like OPC, GPC exhibits comparable mechanical
properties, including strength, fire resistance, chemical resistance, and durability. This review explores the
properties and applications of GPC as a sustainable material in pavement construction, exploring key studies
and advancements in geopolymer technology, particularly its suitability for pavement applications. The
assessment covers the mechanical properties, long-term performance, and environmental impact of
geopolymer-based pavements, providing a comprehensive overview to inform policymakers, engineers, and
researchers about the viability of geopolymer-based materials as a sustainable solution for modern pavement
construction