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Analysing the effect of Covid-19 induced restrictions on rural household's food security : a case of Makhado Local Municipality, Limpopo Province
Get PDFThesis (M. Agricultural Management (Agricultural Economics)) -- University of Limpopo, 2023The country witnessed a major global economic slowdown and increasing disruption
to food supply chains due to the lockdown caused by COVID-19, a global health crisis.
The COVID-19 crisis has negatively affected agri-food enterprises’ ability to ensure
consistent supplies of food to markets due to forced closures, labour shortages caused
by illness, and a decline in operations caused by physical separation and lockdowns.
Understanding the effects of COVID-19 on household food security is critical given the
need to improve food security, especially at household and individual levels.
Given the background information, the study aimed at analysing how COVID-19
induced restrictions have affected rural household food security in Makhado Local
Municipality of Limpopo Province. The study was conducted in the Limpopo Province
of South Africa, at Makhado Local Municipality. The Municipality comprises four
administrative areas, namely, Louis Trichardt, Vleifontein, Waterval, and Dzanani. The
sampling procedures employed for the study were purposive sampling and
proportional random sampling. Primary data were collected from the 139 randomly
selected households using a structured questionnaire with household heads as the
unit of analysis. Household Food Insecurity Access Scale (HFIAS), Household Dietary
Diversity Score (HDDS) and Multiple Linear Regression Model were used to analyse
the effect of COVID-19 induced restrictions on household food security.
Based on the results, the study concluded that, food insecurity increased among
Makahado local municipality rural households during the COVID-19 pandemic, and
the households were concerned about not having enough food. The COVID-19
pandemic robbed the people of their constitutionally protected right to sufficient food,
weakening efforts to achieve “Zero Hunger” by 2030 under the National Development
Plan and the United Nations Sustainable Development Goals. Furthermore, the results
revealed a significant unemployment rate and low-income status rate, as most
members of the households depended on social grants for income, severely limiting
the extent of household food security. According to the findings of the study,
employment is an important factor in ensuring household food security. Remittances
have been discovered to be a critical tool for many households in the research area,
and increased concentrations of remittances can significantly alleviate food insecurity
and the implications of income inequality. Policymakers in emerging economies can
focus on ensuring job security to mitigate the negative effects of income inequality
while lowering remittance transaction costs.
The study, therefore, recommends that the government solves this problem by
enacting appropriate policies and allocating subsidies to lower-income deciles,
allowing essential food items such as protein and micronutrient sources to enter
people’s food baskets. More emphasis should be placed on the implementation of
feeding schemes to decrease the burden on the poor while also making it easier for
youths to attend school. All innovation stakeholders, including rural recipients, must
be involved in every step of improving rural livelihoods. A thriving and dynamic
agricultural sector is a critical pillar of rural development, generating strong ties to other
aspects of the economy. Rural livelihoods are improved when rural communities and
individuals actively participate in the management of their own social, economic, and
environmental affairs
Removal of organic dyes from textile wastewater using green synthesized metal oxide heterostructures decorated carbon-based nanomaterials
Get PDFThesis (Ph.D. (Chemistry)) -- University of Limpopo, 2023Despite the persistent problem of water scarcity, water resource contamination is on
the rise because of the growing trend of urbanisation and industrialization.
Contaminants, such as dyes and pharmaceuticals due to the textile industry and
excessive usage of antibiotics have been detected in natural water sources. Hence, it
is of high importance to remove or remediate such contaminants in water. TiO2 and
ZnO nanoparticles are among the metal oxide semiconductor catalysts, which have
been popularly used to remove a variety of contaminants in water. Unfortunately, these
photocatalysts have various limitations such as wide bandgaps, rapid recombination
rates, low surface areas, and their various synthetic routes use of hazardous reagents
as reducing and stabilizing agents, which are a health hazard. In this study Commelina
benghalensis (C. benghalensis) plant extracts were used to synthesize ZnO, TiO2,
CuO-TiO2, 20/80 ZnO-CSs, (20/80) TiO2-CSs, CuO-TiO2-CSs, CuO-ZnO-CSs, 1 %
Ag-ZnO-CSs. The novelty of the study focuses on the first time utilization of C.
benghalensis plant extracts as greener and safer alternative way to synthesize all the
photocatalysts that were environmentally friendly. To reduce the large bandgap of TiO2
and ZnO, these were coupled with CuO, to increase the surface areas these
photocatalysts (TiO2, CuO-TiO2, ZnO and CuO-ZnO) were loaded on carbon materials
and doping carbon-based photocatalysts with noble metals (Au and Ag) to help the
recombination rate and increase the active sites, resulting in an enhanced
photodegradation process.
The sections (Chapter 4-8) explored the synthesis of ZnO, TiO2, CuO-TiO2, CSs, 20/80
ZnO-CSs, (20/80) TiO2-CSs, CuO-TiO2-CSs, CuO-ZnO-CSs, 1 % Ag-ZnO-CSs and 1
% Au-doped ZnO-CSs using various concentrations of C. benghalensis plant extracts.
Various Characterization techniques such as FTIR, XRD, SEM, PL, TGA, BET, and
UV-vis were used to characterise the photocatalysts.
The FTIR revealed that tannins and flavonoid compounds from the plant were
deposited on the photocatalysts; the peaks corresponding to the phytochemicals were
more intense, when increasing the concentration of plant extracts. The presence of
Zn-O and Ti-O-Ti vibrations were observed in the fingerprint region. More compounds
such as alkaloids, esters, phenols, carboxylic acids etc. from the C. benghalensis plant
extracts were confirmed by the LC-MS. The FTIR confirmed the presence of tannins
and flavonoid, Cu-O and Ti-O-Ti peaks. An FTIR spectrum of microwave-synthesized
carbon spheres showed the presence of carboxylic bond O–H, aliphatic groups
asymmetric to the C–H, carbonyl stretch –C=O of carboxylic groups, the presence of
C–C vibrations of aliphatic groups and the C-H vibrations. Therefore, the formation of
carbon spheres was confirmed. Various photocatalysts were deposited on the CSs
materials and the resulting
FTIR spectra of various ZnO-CSs (5, 10 and 20 %) nanocomposites showed the
presence of alkane molecules, hydroxyl, carboxylate, and carboxyl moieties. The
metal-oxygen (Zn–O stretching vibrations), C–N bond stretching of the primary amine
(which implies the presence of phytochemicals), asymmetric C–H, carboxylic groups,
C=C stretching and C–C vibrations of aliphatic groups were also detected. The
intensity of the ZnO peaks increased with the load percentage of ZnO on CSs. More
peaks of the CSs were observed on the 5/95 ZnO-CSs than 10/90 and 20/80 ZnO-
CSs nanocomposites. The formation of ZnO-CSs was confirmed by this spectrum.
The 20/80 TiO2-CSs FTIR spectrum depicted the presence of Ti–O–Ti, Ti–O, and O–
Ti–O bonds,–C–C–, H–O–H bonds and the C=O stretching of the carboxylic acid. The
peaks at 1847-2158 cm-1 were attributed to the aliphatic –C–H, O-H. There was
successful deposition of TiO2-NPs on CSs. For the CuO-TiO2-CSs, FTIR spectra
showed Cu–O bond, O–H, Ti–O, Ti–O–Ti, C–H, –C=O and the C–C. These results
confirmed the presence of CuO, TiO2 and CSs groups. The FTIR spectrum for the
20/80 CuO-ZnO-CSs reported the presence of the Zn–O, Cu–O bonds, C–H, C=C, O–
H, –C=O and C–C groups. The functional groups clearly depicted that the sample
contained CuO, TiO2 and CSs. However, as we were doping the ZnO and TiO2
photocatalysts with CuO, Au, Ag and loading the materials on CSs it is important to
note that the intensity of peaks corresponding to the tannins and flavonoid compounds
was decreasing.
The XRD confirmed the formation of hexagonal wurtzite phase of ZnO and anatase
phase TiO2 and a mixture of rutile and anatase phase. XRD confirmed the anatase
phase of TiO2 and the tenorite phase of CuO. There was only one phase of TiO2 in the
composite as compared to the pristine TiO2. The CSs XRD patterns noted the
distinctive carbon peak at 21, 9°, which corresponds to the (002) plane was identified.
The phase of the carbon spheres was amorphous, however the (100) plane of this
material was not visible. The XRD pattern of ZnO-CSs (5, 10 and 20%) nanocomposites showed a broad peak
at 21.6 associated to CSs, while the peaks associated ZnO are strongly suppressed
by the incorporation of CSs.
For the 20/80 TiO2-CSs XRD patterns intense diffraction peaks were visible in all TiO2,
while crystalline TiO2 significantly suppressed CSs peaks. This is closely related to the
charge recombination rate, making it favourable for photocatalytic activity. No
additional impurity-related peaks were discovered. This indicated that the TiO2-NPs
formed a clear anatase phase. The XRD data did not correlate with the FTIR data as
various C-C groups were confirmed in the presence of CSs in the sample. The 2θ
diffraction peaks for 20/80 CuO-TiO2-CSs corresponded to the CuO tenorite structure
and the anatase phase of TiO2. This makes sense given that the lattice constants of
anatase TiO2 are identical to those of CuO (tenorite). The intensity of TiO2 peaks is
greater than that of CuO, indicating that TiO2 contributes more to the composite. All
characteristic peaks related to TiO2, CuO, and no characteristic peaks associated
impurities were observed. It was also discovered that the CuO-TiO2 phases did not
change during composite formation and remained in anatase phase, and that its
crystalline structure remained constant after aniline polymerization.The crystallinity
20/80 CuO-ZnO-CSs was investigated using XRD crystallography, CuO-NPs on CuO-
ZnO compositions of varying percentages showed various peaks at 2θ angles that
were assigned to tenorite CuO-NPs and the polycrystalline wurtzite ZnO-NPs. No
visible peaks were detected for all the CSs sample, which means the sample is highly
crystalline while the prepared was highly amorphous. It can be deduced that the CSs
peaks were too small to even be identified since the presence of the CSs in the sample
was detected by the FTIR spectra.
The XRD patterns 1 % Ag-ZnO-CSs and 1% Au-ZnO-CSs diffractogram showed
distinct peaks correspond to carbon sphere planes, hexagonal wurtzite structure,
metallic silver and gold. The peaks corresponding to the ZnO-NPs were very small this
may be due to the quantity of ZnO in the entire sample as only 20 % of ZnO-NPs was
added.
The UV-Vis displayed a maximum absorption band between 300 nm, 301, 5 nm, 280-
350 nm and 290-300 nm for CuO-ZnO, CuO-TiO2,10-30g ZnO and TiO2-NPs,
respectively.
v
The UV-Vis absorption band for the CSs materials shows a broad peak around 300
nm and a shoulder around ~280 nm. These peaks can be attributed to →*
transitions of aromatic C–C bonds and → * transitions of C=O bonds, respectively.
All the ZnO-CSs exhibit a broad absorption peak at 300.7 nm and a shoulder peak
around 287.5 nm. The absorbance band at 300.7 nm decreased with the increasing
load percentage of ZnO on the CSs. While the shoulder peak around 287.5 nm was
increasing in visibility with the increasing load of ZnO on CSs materials. There was no
visible shift of the CSs peaks on the composite samples. The nanocomposites
obtained in this study exhibited a slight move towards the infrared region as compared
to the bulk ZnO, this is due to CSs chemical interaction with ZnO-NPs.
UV-Vis absorbance spectroscopy of the (20/80) TiO2-CSs nanocomposites showed
only one maximum absorbance sharp peak was visible at 285.7 nm. The addition of
the TiO2 on the CSs material shifted the absorbance band to the lower UV region. The
results indicate that the nanocomposites were more active in the UV region than the
visible region of the spectrum. There were two broad peaks that were present in the
20/80 CuO-TiO2-CSs samples, the peaks were around 300.6 and 286.8 nm. The CuO-
TiO2 nanocomposite exhibited a shift towards the UV region of the UV-vis absorption
spectra, therefore the carbonaceous species in the as-synthesized 20/80 CuO-TiO2-
CSs did not shift the material to the visible region. It is important to note that the carbon
spheres synthesized in these studies were calcined via various temperature, while the
CSs synthesized in the study was not calcined. The UV-Vis spectra for CuO-ZnO-CSs
shows two peaks around 286.7 and 300.6 nm. Therefore, these materials were not
active in the visible region of the spectrum. The UV-vis spectrum did no show improved
optical properties on the CSs materials.
The doped 1% Ag-ZnO-CSs and 1% Au-ZnO-CSs UV-Vis spectrum 301 nm and 287
nm, corresponding to ZnO and CSs, respectively. The 1% Ag-ZnO-CSs showed
absorption bands at 298 nm and 286 nm, which are the absorption peaks Ag, ZnO-
CSs, respectively.The presence of Ag caused a blue-shift in the absorbance spectrum
as the maximum absorbance peak for Ag-ZnO-CSs is at 298 nm instead of ~301 nm,
which was reported in chapter 7. The surface plasmon band of 1 % Ag-ZnO-CSs
composite was noticeably broadened due to the strong interfacial electronic coupling
between neighbouring ZnO and Ag nanoparticles. This plasmon oscillation may have
vi
caused a stronger light scattering influenced by the interaction of incident light and Ag
nanoparticles, which helps to lengthen the optical path and reduces light energy loss
even further.
A band around 290 nm was recorded for the 1% Au-ZnO-CSs, which shows the
presence of the Au in the ZnO-CSs material. The shift in ZnO band position in 1% Au-
ZnO-CSs nanoparticles can be attributed to gold's higher electronegativity than silver.
As a result, gold draws more electron density towards itself, affecting the movement
of the band position of ZnO.
The addition of photocatalysts and noble metals influenced the CSs material to be
more active in the UV then the visible region of the spectrum.
The bandgaps between 3.0-3.75 eV and 3.69-3.80 eV were obtained in ZnO and TiO2-
NPs, respectively. Only the 10 g and 30 g ZnO reported reduced band gaps of 3.0 and
3.19 eV, respectively. The bandgap of CSs was reported to be 3.8 eV. The calculated
the bandgap values were 3.8 eV, 3.5 eV and 3.78 eV 5/95 ZnO-CSs, 10/90 ZnO-CSs
and 20/80 ZnO-CSs respectively. The bandgaps for the CuO, CuO-ZnO, CuO-TiO2
30/70, CuO-TiO2 50/50 and CuO-TiO2 70-30 were found to be 3.7 eV, 3.49 eV, 3.76,
3.72 eV and 3.79 eV, respectively. The obtained bandgaps are larger than 3.2 eV
bandgap for the bulk ZnO, but smaller than the bandgap of CSs (3.8 eV). On the other
hand, the bandgaps for 20/80 TiO2-CSs, CuO-TiO2-CSs and CuO-ZnO-CSs were 4.1
eV, 3.56 and 3.19 eV. Only the 20/80 CuO-ZnO-CSs reported the smallest bandgap
of 3.19 eV.
The corresponding bandgap of 3.75 eV for the 1% Ag-ZnO-CSs was calculated by
extrapolating the linear region of the Tauc’s plot. This is because the nanocomposites
synthesized in this study were active in the UV region rather than visible region. The
bandgap of the 1% Au-ZnO-CSs was found to be 3.79 eV,. The presence of the Au
NPs must have played a major role in the optical properties of the materials as these
materials shifted to the lower UV region. The improvements on optical properties of
these materials were insignificant.
The Image J displayed particle size distributions of 60-80, 2-28 and 8-12 nm, for 10-
30 g ZnO-NPs and 100-300, 75-125 and 50-2 nm for 10-30 TiO2-NPs from the
obtained SEM images of the photocatalysts. In chapter 4 and 5, SEM Images for both
TiO2 and ZnO reported bigger particle sizes for lower concentration of the plant, since
vii
only fewer capping and reducing agents were present. Spherically-shaped materials
were observed. The Image J reported particle size distributions of 50 nm–250 nm 100-
200 nm, 125-250 and 105-250, for CuO, CuO-TiO2 30-70, 50-50 and 70-30 was
respectively. The larger particle sizes may be due to the agglomeration that was
observed from CuO-TiO2 30-70 to 70-30. TEM images showed that the CSs were
highly agglomerated, irregularly sized nanospheres, with sizes between ~10 nm to 100
nm. The TEM micrograms of CSs with various loadings of ZnO-NPs had mixed
spherical and rod-shaped particles with a broad length distribution of 25-200 nm. As a
result, when comparing the two nanoparticles, the CSs had larger particles than ZnO-
NPs. TEM micrographs of the obtained 20/80 TiO2-CSs, CuO-TiO2-CSs and CuO-
ZnO-CSs and the corresponding particle size distributions showed sherically and rod-
likeshaped materials with particle size distributions of 25-200 nm, 100-600 nm and 50-
250 nm for 20/80 TiO2-CSs, CuO-TiO2-CSs and CuO-ZnO-CSs, respectively.
The obtained 1 % Ag-ZnO-CSs and 1 % Au-ZnO-CSs nanomaterials TEM images
showed spherically-shaped particles with length distributions ranging from 20 to 100
nm and 50 to 400 nm, respectively. The particles sizes of the noble metal-doped
nanocomposites were smaller 20/80 ZnO-CSs with particle size distributions. The
smaller sizes of materials favours high photocatalytic efficiency against dyes and
pharmaceuticals.
The BET surface areas were reported to be were 11.0723 m2/g, 8.8172 m2/g, and
7.1229 m2/g for 10 g, 20 g and 30 g ZnO-NPs, respectively. For the 10 g, 20 g, and 30
g TiO2-NPs, the BET specific surfaces were 18.3 ± 0.173 m2
/g, 12.3 ± 0.146 m2
/g, and
174.6 ± 1.35 m2
/g, respectively. The surface areas decreased with an increased
concentration of plant extract for ZnO-NPs and TiO2-NPs (10-20 g), while for TiO2-
NPs the 30 g TiO2-NPs had a BET surface area of 174.6 m2
/g. The BET surface areas
were 5.58, 5.74 and 3.22 m2
/g for CuO-TiO2 30-70, 50-50 and 70-30,respectively. The
20/80 ZnO-CSs nanocomposite had a surface area of 21.95 m2
/g (Figure 7.10b). The
isotherm (demonstrated a hysteresis loop of type H2, indicated a mixture of
macropores and mesopores while the BET surface area curves for the 20/80 TiO2-
CSs, CuO-TiO2-CSs and CuO-ZnO-CSs can be classified as a typical type IV
isotherm, which belongs to a hysteresis loop type II indicating a purely mesoporous
material with small pore sizes. The BET surface area was 1.676 m2
/g, 2.890 m2
/g
viii
and 40.740 m2
/g for 20/80 TiO2-CSs, CuO-TiO2-CSs and CuO-ZnO-CSs,
respectively.
The thermal stability of both ZnO and TiO2-NPs decreased with increasing
concentration of plant extract. The final weight % at 900 0C for 10-30 g were 98.9, 93.2
and 84.6 % for ZnO-NPs and 97.9, 96.4 and 96.4 % for TiO2-NPs ,therefore, these
materials were highly stable under extremely high temperatures therefore suitable for
photocatalysis. Three CuO-TiO2 materials were thermally stable as only a maximum
of ~8 % weight loss was noted for the 70/30 CuO-TiO2 at 900 0C. Nanocomposites
were slightly less stable than green synthesized TiO2 as the maximum weight loss of
~4 % was reported. The TGA analysis of CSs reported a total mass loss of CSs was
about 50 % at 900 0C. These CSs were thermally unstable at higher temperature this
means the addition of our photocatalysts on the CSs will increase their stability.
TGA curves of 20/80 ZnO-CSs (Figure 7.9a) show a slow rate of weight loss of 10 %
up to 100 0C, indicating that volatile substances and water in the samples evaporate
[390]. The second stage of weight loss occurred between 105 and 200 0C (3.7 %
weight loss) due to the dehydration of water within the ZnO structure [423], and the
final stage between 200 and 900 0C (46.1 % weight loss) to the decomposition of ZnO-
CSs. The thermal stability and the derivative of (20/80) TiO2-CSs, CuO-TiO2-CSs,
CuO-ZnO-CSs and ZnO-CSs showed that only 44.7 % of weight was lost at 900 0C.
The TGA revealed about 49.9% weight loss at 900 0C for the CuO-TiO2-CSs and the
TGA of 20/80 CuO-ZnO-CSs nanocomposites showed the most stability than the
(20/80) TiO2-CSs and CuO-TiO2-CSs nanocomposites as about 43.1% weight was
lost at 900 0C compared to the 44.7 % and 49.9 % of (20/80) TiO2-CSs and CuO-TiO2-
CSs, respectively. Adding the photocatalysts to the CSs improved their thermal
stability.
1 % Ag-ZnO-CSs and 1 % Au-ZnO-CSs structures and the final stage between 400
and 900 0C a total weight loss of 64.3 % and 69.6 % was reported, respectively. These
results show that the 1 % Ag-ZnO-CSs is more thermally stable than the 1 % Au-ZnO-
CSs. And that both materials are less stable than the 20/80 ZnO-CSs, as the total
weight percentage at 900 0C was approximately 54.2 %, 36.4 % and 29.7 % for 20/80
ZnO-CSs, 1 % Ag-ZnO-CSs and 1 % Au-ZnO-CSs, respectively. 74.2 % at 700 0C for
the Ag-doped ZnO-C material.
ix
The highest degradation of 81 % for methylene blue (MB) was reported by 30 g ZnO-
NPs while the 30 g TiO2-NPs reported 65 % degradation of MB. The degradation of
sulfisoxazole (SSX) was 42 % and 82 % for 30 g ZnO and 30 g TiO2-NPs, respectively.
Both ZnO and TiO2-NPs were only reusable once and the •OH were the species
responsible in the degradation of MB. Degradation of MB was 14, 33 and 12 % for
30/70, 50/50 and 70/30 CuO-TiO2. The degradations of SSX and ciprofloxacin (CIP)
were 93.6, 93.2 and 91.2 %, respectively. While for the 30/70, 50/50 and 70/30 CuO-
TiO2, the degradations were 5.06, 55.3 and 67.3 %, respectively.
On the photodegradation analysis various photocatalysts of CSs, 20/80 TiO2-CSs,
CuO-TiO2-CSs, CuO-ZnO-CSs and 20/80 ZnO-CSs were tested for their efficiency
against MB dye using similar MB conditions that was reported in Chapter 4-6. The
highest degradation of CSs, TiO2-CSs, CuO-TiO2-CSs, CuO-ZnO-CSs and (5 %, 10
% and 20 %) ZnO-CSs was ~25, 36, 41, 40, 36 and 42 %, respectively. From these
values it can be noted that the addition of photocatalysts on the CSs improved only
the degradation efficiency of the CuO-TiO2 (Chapter 6) nanocomposites against MB.
Since the highest degradation efficiency of CuO-TiO2 nanocomposites was reported
to be 33 %. While the addition of CSs regressed the degradation of ZnO and TiO2
against MB as the highest degradation was reported to be 81 and 65 %, respectively
(Chapter 4 and 5) The majority of materials achieved the first order of kinetics
because the R2
is closer to 1. The reaction rate for CSs was 0.0025 min-1
. While the
reaction rates for 5/95 ZnO-CSs, 10/90 ZnO-CSs and 20/80 ZnO-CSs were 0.004,
0.003, and 0.003 min-1
, respectively. The reaction rates of 0.0023, 0.0028, and 0.002
min-1 were reported for the (20/80) TiO2-CSs, CuO-TiO2-CSs and CuO-ZnO-CSs
respectively.
The highest degradation rates of 75 %, 92 % and 98 % for the 20/80 ZnO-CSs, 1 %
Ag-ZnO-CSs and 1 % Au-ZnO-CSs, respectively were found. The synthesized 20/80
ZnO-CSs, 1 %Ag-ZnO-CSs and 1 % Au-ZnO-CSs nanocomposite did not achieve the
first order of kinetics because the R2 was not closer to 1. The reaction rates of 20/80
ZnO-CSs, 1% Ag-ZnO-CSs and 1 % Au-ZnO-CSs were 0.00368, 001017 and
0.00196, respectively. The 20/80 ZnO-CSs, at optimum conditions ( pH5, 45 mg
dosage, 5 mg/L dye) showed a slight improvement and had the highest degradation
of 75%.
x
Studies reported that the ZnO-CSs exhibited improved photocatalytic activity under
sunlight and visible light irradiation after the addition of CSs, which is attributed to the
CSs' extended light absorption range and fast separation of photogenerated charge
carriers. The findings of this study are almost comparable to those of other studies
published in the literature where UV, visible and sunlight light sources were used to
degrade organic materials using similar nanocomposites.
During photocatalysis, trapping studies were carried out to assist understand the
reaction mechanism and identify the reactive species involved. Chemical species such
as tert-butanol, EDTA, AgNO3, and p-benzoquinone (BQ) were used as •OH radicals,
holes (h+
), electrons (e-
) and superoxide ion (O2
2-
) trappers and scavengers in the
reaction system, respectively.
For the ZnO-NPs only the 30 g of ZnO-NPs was used against the MB for all the
trapping studies. It was noted that the addition of the EDTA decreased the degradation
by 30% which meant that the presence of the electrons (e-
) played a minor role in the
photodegradation of MB. In opposition, the addition of t-BuOH and AgNO3 decreased
the photocatalytic degradation of MB by 49 % and 54 %, respectively. The addition of
t-BuOH affected the degradation of MB, the most compared to the AgNO3 and EDTA,
indicating that the •OH.radicals were the main active species.
Similar procedure was followed for the TiO2-NPs as the degradation of MB with 30 g
TiO2-NPs was used for all trapping studies. The addition of EDTA and AgNO3
increased the degradation by 17 and 3 %, correspondingly, implying that the presence
of both electrons (e-
) and holes (h+
) did not play a role in degrading the MB dye
comparing to the other species. The addition of t-BuOH resulted in 34% reduction in
An investigation of the challenges faced by women-owned small-medium enterprises in the Makhado Local Municipality, Limpopo Province
Get PDFThesis (MBA.) -- University of Limpopo, 2023For decades, business has been a male-dominated activity, but recently, a considerable number of female entrepreneurs have emerged around the world. One of the factors that motivate women to become entrepreneurs is the flexibility offered by self-employment. Self-employment allows people to better manage their work-life. However, there are challenges experienced by women entrepreneurs in growing their businesses. These challenges may be due to the fact that women have a wide range of responsibilities both at work and at home that affect their productivity. Multiple family tasks and responsibilities for women entrepreneurs may cause work-family conflict, which could jeopardise their long-term business success. Therefore, the objective of this study was to look into the difficulties faced by women-owned small businesses in the province of Limpopo's Makhado Local Municipality. In this study, a thematic data analysis approach was applied. Qualitative in nature and approach, the study relied on face-to-face interviews to collect the data. It was found that most women start small enterprises because they are compelled by outside forces such as unemployment and poverty. Furthermore, qualification and experience play an important part in operating a business. The findings also indicate that women-owned small medium enterprises do not get any financial support, training from the government or private sector. Hence, they rely more on their family for any support. Women who own small-medium enterprises also encounter discrimination in various forms, including being told that they ought to remain at home and take care of the family mainly because they are women. The study recommends that financial assistance, training, women networking, infrastructure, awareness campaigns and implementations of legislation meant to assist women-owned small-medium enterprises should be prioritised
Investigation of inbreeding rate and its influence on stillbirth in South African Holstein African dairy cattle
No full textThesis (M.Sc. Agriculture (Animal Production)) -- University of Limpopo, 2024There is no study done at the population level on stillbirth in Holstein dairy cattle population of South Africa. The current study was conducted to evaluate the inbreeding rate and its influence across generations on incidences of stillbirth in South African Holstein dairy population. The dataset included about 1 million Holstein dairy cattle born between the year of 1945 to 2020. Pedigree information included animal ID, sire ID, dam ID, breeder and farm region, other information included date of birth, calf sex, dam parity and age at parturition, calving date, herd, and birth status. Generation intervals were determined using ENDOG software (version 4.8), while General Linear Model (GLM) procedure at 5% significant level was used to model incidences of stillbirth. Phenotypic trends were determined using regression procedure, and SAS was used to analyse regression of inbreeding rate effect on the incidences of stillbirth per generation. Effective population size, inbreeding coefficients and inbreeding rate were estimated using Contribution Inbreeding Coancestry (CFC) software. The results indicated that dam parity, herd, calf sex, generation, birth season and birth year had a significant effect (P<0.05) on the incidences of stillbirth. The multiparous, autumn (3.397±0.067), summer (3.306±0.067), and female calves (3.516±0.046) had high incidences of stillbirth than primiparous, spring (3.073±0.067), winter (3.00±0.063 and male calves (2.922±0.028). Stillbirth incidences were observed to increase with birth year and generation, while decreasing with an increase in dam parity and dam age. Incidences of stillbirth was very different across the herds ranging from a minimum of 0% and a maximum of 100%, however most of the herds had zero incidences of stillbirth (3.736±0.251). This indicated that stillbirth problem in South African Holstein dairy population is at the herd level not at the population level. Inbreds were only 0.48% of the population, with an average inbreeding coefficient ranging from 2.48% to 24.60%. Average discreet generation equivalents (DGE) approximated one for most generations, with a range of 0.226 to 1.256, this highlight that majority of the generations were complete. Animals in the 1st to the 12th generation were closely related, while from the 12th to 14th generation they were less related to each other. Inbreeding coefficients ranged from 0.0020% to 0.1099%, with inbreeding rate increasing per generation and recording the lowest value (0.0479) and the highest (0.5536) in the 13th and 2nd generations respectively. Effective population size was observed to depend on the number of breeding males, with the 2nd generation showing lowest number of breeding males (23 sires) and the lowest effective population size (90.3), while the 13th generation had the highest number of breeding males (264 sires) and the highest effective population size (10447.7). The regression model was observed to be statistically significant (P<0.05) with R2 value of 88.61%, however the evaluated factors; number of individuals, no of inbreds, no of founders, average F, average F in the inbreds, effective population size and inbreeding rate were not significant on incidences of stillbirth. Inbreeding rate in the current study had a significant effect on stillbirth incidences in the South African Holstein population. Stillbirth incidences increased with effective population size with an R square of 12% but decreased with an increase in inbreeding rate and average inbreeding coefficients in the inbreds, with R square values of 13% and 20% respectively. Inbreeding contributed only 20% towards the stillbirth incidences indicating that stillbirth in the South African Holstein population is caused by other factors other than the inbreeding. Stillbirth incidences increased with effective population size and a reduced with an increase in average inbreeding coefficients in the inbreds. However, generations increased with stillbirth incidences and effective population size with R2 of 60% and 92% respectively, indicating that generation had 60% contribution to stillbirth incidences. Generation increased with a reduction in inbreeding rate and average inbreeding coefficients in the inbreds with R squares of 35% and 53% respectively. Stillbirth incidences in the South African Holstein population is not caused by the genetic factors such as inbreeding rate, this can be because stillbirth is a lowly heritable trait meaning it is more affected by environmental factors other than genetic factors.National Research Foundation (NRF)
University of Limpopo (UL)
Agricultural Sector Education Training Authority (AgriSETA
The role of ubuntu in conflict resolution : the case of the Malamulela and Vuwani conflict in Vhembe District, Limpopo Province
Get PDFThesis (Ph.D. (Anthropology)) -- University of Limpopo, 2023This thesis explores the role of Ubuntu in conflict resolution in the communities of
Malamulele and Vuwani, located in Vhembe District of Limpopo Province, South Africa.
Despite the decline in the current South African liberal democracy and the challenges that it faces with respect to its restoration, Ubuntu remains pivotal to conflict resolution.
Nevertheless, there is hope for the restoration of Ubuntu on condition of a proper and diligent implementation of the tentative Ubuntu Conflict Resolution Model (UCRM), outlined in this study. The study utilised qualitative research methods to explore the role of Ubuntu in conflict resolution in the case of the Malamulele and Vuwani conflict. As a decolonised anthropological study, it examined African human behaviours and cultures with a view to comprehending the society. Based on primary data collected from interviews, the role of Ubuntu in the conflict was uncovered. The entire study utilised Ubuntu as a theoretical framework to analyse the data provided by the participants. The study found that Ubuntu remains a useful tool to unify, amend, heal, reconcile, and maintain broken relationships, if it is restored adequately. However, the study identified a decline of Ubuntu among the Malamulele and Vuwani community members, but the hope is there for Ubuntu to thrive again since there are some members of the communities who still hold Ubuntu and if steps suggested in this study could be taken into consideration. It was discovered that Ubuntu is an independent variable, and fosters quality traditional, family, educational, religious and political leadership. Quality education is enhanced by Ubuntu as its philosophical foundation. In fact, Ubuntu requires environments that are conducive to its own survival; without these environments it may struggle to exist. The study suggested a tentative UCRM; a model that may be used in the communities of Malamulele and Vuwani to resolve conflict on a shortand long-term, bases. While some of the cultural practices of traditional leadership families such as human sacrifice are controversial and unacceptable considering the values of Ubuntu and their roles as cultural custodians of social justice and human rights, the study recommended further descriptive investigation which will look at Ubuntu in traditional leadership practices in contemporary South Africa. Nevertheless, the study has shown that Ubuntu has a place and role to play in the new liberal democratic society since the hope for its restoration is still there
Perception of pharmacy graduates and pharmacy employers on internship programme in public hospitals in Limpopo Province, South Africa
Get PDFThesis (M. Pharm.) -- University of Limpopo, 2023Introduction: The South African Pharmacy Council(SAPC)stipulates that upon completion of the pharmacy qualification, newly qualified pharmacists should complete a compulsory one-year internship programme for a minimum of 12 months under the direct supervision of a registered tutor in a registered training premise as approved by the SAPC. Although there are guidelines and manuals in place for the Pharmacy internship programme, there is no sufficient evidence that the programme serves its original purpose. Aim: The study aimed to evaluate and explore the pharmacy graduates' and employers’ perceptions of pharmacy internship programme in public hospitals around Limpopo Province. Method: The study was conducted at public hospitals in Limpopo Province. The study used a mixed method design; in particular explanatory sequential design. Phase 1 was conducted using a self-administered questionnaire and phase-2 was conducted using semi-structured interviews. The study population for phase 1 was 182.The participants for phase 1 were sampled using total sampling method. For phase-2 data saturation was reached at participant 13, the participants were selected using purposive sampling. Results: The findings in phase 1 revealed that majority of the participants perceive the pharmacy internship to be effective. They also indicated that the pre-registration examination and continuous Professional development play a role in preparing pharmacy graduate’s competency, however majority of participants disagreed that the costs of the pharmacy internship registration are reasonable. Phase 2 results showed that participants perceive the internship as being effective because of how it boosts participant’s confidence and how it is a transition tool into real work setting. They also mentioned that cpds and pre-registration exam are important because they keep health personnel updated on policies. Conclusion: The internship programme is effective through its system of CPDs and pre-registration, the CPDs and pre-registration examination are vital components in preparing interns towards their career paths as pharmacist, but there is a need to increase tutors and pharmacists’ participation into the programme. Recommendations: It is recommended that the SAPC to hold venue based internship workshops for both interns and tutors frequently. The Limpopo Department of Health and SAPC to find fixed hospital rotational system and to allow training only at tertiary and academic hospitals. The department to develop a swift process of allowing interns to pay the registration costs in instalments gradually
A phenomenological study of the lived experiences of home-based caregivers of patients with chronic mental illness in Ga-Dikgale, Limpopo Province
Get PDFThesis (M. A. (Psychology)) -- University of Limpopo, 2023Previous studies have investigated caregiving within the family unit when a family
member takes the role of the primary caregiver. These caregivers often experience
many physical, emotional and psychological challenges such as anxiety, depression
and stress. The present study sought to explore lived experiences of home-based
caregivers of people living with chronic mental illness in Ga-Dikgale, Limpopo Province,
South Africa. Eight caregivers of family members with chronic mental illness were
sampled from Ga-Dikgale, Limpopo Province, South Africa, and requested to participate
in the study. Data were collected through in-depth, semi-structured, individual face-toface
interviews, and analysed using Hycner’s phenomenological explication process.
The following themes were extracted from participants’ narratives. The role of homebased
caregivers and their understanding of mental illness; challenges that they
encountered; their coping strategies; support systems available for them; their
psychological well-being; and suggestions for improvement. The study is concluded by,
among others, recommending a collaborative approach amongst the Department of
Health, NGOs and community healthcare services to facilitate support for home-based
caregivers
Perceptions of traditional health practitoners on the possibility of collaboration with western trained mental health practitioners in treating mental illness
Get PDFThesis (M.A. (Psychology)) -- University of Limpopo, 2023This study aimed to explore the perceptions of traditional health practitioners in Sekhukhune District, Limpopo Province on the possibility of collaboration between themselves and the Western-trained mental health practitioners in treating mental illness. The objectives were: a). to identify factors that can facilitate collaboration between traditional health practitioners and Western-trained mental health practitioners in treating mental illness; b). to establish traditional health practitioners’ perceived barriers towards collaboration with Western-trained practitioners. Furthermore, the study sought c). to determine the traditional health practitioners’ sentiments regarding the existing legislation and policies that recognise their system; and, d). to determine and document the perceptions of traditional health practitioners on the ideal governance structures that will manage sustainable collaboration and interdependency of the two systems. The study adopted a qualitative research approach and a descriptive phenomenological research design. Twelve participants (females = 3; males = 9) aged between 29 and 59 years were selected through purposive sampling and interviewed using semi-structured interviews. Data were analysed through thematic content analysis. The key themes that emerged from the data related to: a). participants’ views on the causes of mental illness; b). participants views on the diagnostic and treatment procedures for mental illness; c). perceived facilitators for collaboration between traditional healers and Western trained mental health practitioners; d). perceived barriers for collaboration between traditional healers and Western trained mental health practitioners; e). participants’ opinions regarding existing policies and legislation; and, f). participants’ views on how the envisaged collaboration could be managed and sustained. The study is concluded by, among others, recommending that the government proceed with the regulation of traditional health practitioners to ease the relationship between the two health system
The implementation of the National School Nutrition Programme (NSNP) for household food security in selected public schools in Malamulela, Limpopo Province
Get PDFThesis (M. Dev. (Planning and Management)) -- University of Limpopo, 2023The goal of this study was to determine whether the National School Nutrition Programme contributes to food security in recipient households, in addition to providing one meal per school day to students. The researcher was interested in whether the programme had a long-term effect on households rather than simply meeting a short-term need. The researcher chose the interpretivist paradigm for the study, since it was likely that participants would have different perspectives on the same programme, and it is these perspectives which the researcher sought to uncover. This study made use of qualitative research methods. The schools selected are all Quintile 2 schools situated in rural villages in the far north of Limpopo. Many of the learners at the schools come from child-headed or grandparent-headed families; some because their parents work in cities far from home, and others because they rely on social grants for income. The study's findings indicate that the programme has an impact in terms of ensuring daily meals at schools for students, which is a short-term need, and goes some way to meeting household food security needs, but is insufficient to have any significant effect, being neither regular nor sustainable. In light of this finding, the researcher has made nine recommendations that may contribute to the provision of sustainable household food security for households in Limpopo Province by the National School Nutrition Programme, based on its existing policy, principles and goals
Knowledge retention at the University of Limpopo's research administration and development in the Limpopo Province of South Africa
No full textThesis (M. (Information Studies)) -- University of Limpopo, 2023Knowledge retention (KR), among research departments at higher education institutions throughout the world, has developed into the most important and crucial element for preserving knowledge. The study was conducted at the University of Limpopo research's Department of Research Administration and Development (DRAD) in the Limpopo Province of South Africa. The objectives of the study were to: Identify strategies used at the UL‘s DRAD to retain knowledge, establish the role of ICTs as tools and enablers of KR, assess the impact of knowledge loss at the UL‘s DRAD, to determine the barriers of KR within the UL‘s DRAD and to propose strategies that can improve KR at the UL‘s DRAD.
This study used a qualitative research approach guided by a conceptual framework derived from the following theories: The KR Framework, the Theory of Organizational Knowledge Conversion, and the Model for Improving Higher Education Research Output, along with an interpretivist paradigm, which works well in qualitative studies. Total population sampling, also known as non-probability sampling, was employed to sample 13 research officials and 5 HR managers. Given the COVID-19 requirements and regulations, the researcher conducted interviews by phone, Zoom, Google Meet, or online questionnaires, depending on the respondent's convenience. Thematic analysis was used to analyse the data.
The found that UL‘s DRAD use e-mail, computers/ laptops, ITS enabler, workshops, seminars, and internet and intranets as strategies to retain knowledge. The study also found that ICTs is a great enabler of knowledge retention and optimisation of daily duties at UL‘s DRAD. Moreover, the study established that the impact of knowledge loss at UL's DRAD result in unrecovered expertise. As a results, the researcher recommends the UL‘s DRAD should put in place knowledge recovery initiatives to deal with the consequences of knowledge loss and stop further occurrences. Other results indicate that UL‘s DRAD encounters barriers in storing and sharing employees‘ knowledge. The impediments are a lack of knowledge storage systems and databases to store knowledge of the employees. These impediments have been found to negatively affect the performance of the UL‘s DRAD officials‘ duties, since there is lack of knowledge and expertise transfer between co-workers.
Proposed KR strategies which are needed to improve KR were identified as linking ICTs to with the UL's DRAD employees, putting organisational knowledge on electronic databases and HRM initiatives (Performance appraisals and employee rewards). Therefore, the researcher recommends that the UL's DRAD to employ these strategies to maintain the staff as well as the knowledge that their people have acquired