College of Natural Sciences (CoNAS)

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    Absence of inter-hall sports competitions for the disabled in Makerere University.
    (Makerere University, 2023-11) Malikisi, Thomas
    In a quest to explore the experiences of students with disabilities and their involvement in sports activities at Makerere University, this research embarked on an insightful journey. The study, rooted in a survey research design, engaged a diverse group of participants. Forty-six students with disabilities from various halls of residence and one dedicated sports coach constituted the focal point of this research endeavor. Fifty four percent (54%) of the students participated in a range of sports, including goalball, athletics, football, volleyball, and netball with 11% engaging in interhall sports competitions. While 67% of the students expressed an earnest interest in inter-hall sports, a whopping 72% believed that the University's efforts to promote awareness and accessibility of adapted sports were wanting. The positive impact of sports participation shone through, with 96% of students reporting benefits to their physical and mental health. Physical rewards, social connections, fitness enhancements, self-acceptance, and even the simple joy of competition were among the cherished rewards of participation. Nearly half of the students (46%) encountered negative attitudes, discrimination, and segregation during sports activities. They faced a barrage of challenges, from inaccessible facilities to financial constraints and injuries sustained in sports. Despite the challenges, the desire to participate was strong. Motivation came from personal passion, peer influence, and the recognition of the physical, mental, and social benefits of sports. Support and encouragement from coaches, parents, and friends played a pivotal role in nurturing this motivation. The students with disability’s roadmap to a more inclusive and vibrant sports community included accessible facilities, tailored training programs, and specialized equipment, enhanced awareness campaigns, ongoing sensitization efforts, and the organization of adapted inter-hall sports competitions that accommodate diverse needs and abilities.
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    Abundance and distribution of Cyathea manniana in kalinzu central forest reserve, southwestern Uganda.
    (Makerere University, 2021-05-05) Akankwasa, Mark
    This study was conducted in Kalinzu Central Forest Reserve, Southwestern Uganda, to assess the abundance and distribution of C. manniana in primary and secondary compartments of this forest reserve. Abundance or population size of C. manniana in these forest compartments is influenced by both abiotic factors such as moisture and light intensity; and anthropogenic activities like tree logging. Previous researches carried out in Kalinzu Forest Reserve have failed to address the concept of population status of C. manniana but instead they have primarily focused on the identification of this species. Systematic analysis of abundance and distribution of C. manniana was done in Kalinzu Forest Reserve, where principal focus was centered on discovering the variation of these parameters (abundance and distribution) in valleys and on slopes of primary and secondary compartments of this forest reserve. A sampling technique was employed to collect abundance data of C. manniana, 12 plots (each 50mx50m) were marked and 6 plots of these were in the valley and other 6 plots on slope of primary forest; similar number of plots of same area size were marked in the valley and on slope of secondary forest. 468 and 175 individuals of C. manniana were counted in primary and secondary forest plots respectively. Population density was computed and DBH of the counted C. manniana was measured. T- tests for population density were run using SPSS software. Analysis revealed statistically significant difference in population density of C. manniana between valleys and slopes and between primary and secondary forests except between valley and slope of secondary forest; DBH class distributions revealed bell- shaped and irregular shaped population structure patterns hence an indicator of poor population/ regeneration status of C. manniana. These findings on population density and structure provided a revelation for urgency in population restoration and conservation of C. manniana in Kalinzu Forest Reserve.
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    Abundance and diversity of soil macro fauna in the different agricultural systems in kamira sub-county Luwero district.
    (Makerere University, 2021-05-18) Ssango, Ronald
    Different agricultural systems exert different impacts on soil macrofauna abundance and diversity due to different management systems employed. Agricultual systemS assesed included coffee plantation, maize garden, potato garden, cattle farm, banana plantation and uncultivated field. Some soil macrofauna migrate into favourable habitats, some die due to use of chemicals.
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    The abundance of BRUSSONETIA PAPYRIFERA (l.) L'hér ex vent. in Mabira forest central reserve
    (Makerere University, 2022-03-31) Bwengye, James
    Mabira Forest Central Reserve is currently undergoing increasing coverage of an invasive species, Brussonetia papyrifera, that contributes to biodiversity loss in the forest reserve. Several studies have shown that B. papyrifera has the capacity to reduce the abundance of native vegetation by supressing the regeneration and growth of resident vegetation. This study aimed at documenting the abundance of Brussonetia papyrifera in the Buffer and Production Zones of Mabira Forest Central Reserve. The study sites were the Buffer and Production Zones. Systematic sampling was employed in this study. The study used belt transects of 1km and plots of 10m by 10m were laid in each zone. Within each plot, the trees were identified and recorded with the help of an NFA guide and the Makerere University Herbarium. DBH was measured using a tape measure and recorded. The results showed that the density of Brussonetia papyrifera was higher in the Production Zone (874 stems/ha) than in the Buffer Zone (274 stems/ha). The relative density also of B.papyrifera was higher in the Production zone(28%) than in the Buffer zone (8%).This was attributed in part due to the fact that the Production zone had a lower species richness as compared to the Buffer zone .Overall the population structure of Brusssonetia papyrifera in the Buffer Zone formed an inverse J shaped curve indicating a good seedling recruitment and sapling development potential whereas that in the Production zone formed an almost inverse -J- shaped curve with a few anomalies that were attributed to the anthropogenic activities that occur in this zone. Mabira Forest Central Reserve stands a high risk of losing its native species in the years to come given the increase of Brussonetia papyrifera. To avert such a calamity, Control measures for the population of Brussonetia papyrifera should be introduced. Further studies are recommended in studying the effects of B. papyrifera in Mabira Forest Central Reserve
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    Abundance of Lantana Camara in West Bugwe Central Forest Reserve, Busia District
    (Makerere University, 2024) Naamara, Moses
    This research study was carried out in West Bugwe Central Forest Reserve which is found in Eastern Uganda and this reserve is 21 km from Busia town. This study aimed to assess the abundance of Lantana camara within West Bugwe Central Forest Reserve and using random sampling method, 64 plots each measuring 10 ×10 meters were established and sampled to conduct the study. The primary objective of this research was to quantify the presence of Lantana camara and evaluate it's potential impacts on the reserve ecosystems. My findings revealed a significant difference in the abundance of L. camara in the two sampled regions of the forest reserve but with the abundance of L. camara being higher in the disturbed forest region. Furthermore, there was a statistically significant association between the percentage cover of L. camara found in the disturbed forest region and that found in the undisturbed forest region of the reserve. The higher abundance in the disturbed forest region could have been probably because of the high light penetrations that spiked Lantana camara spread in the disturbed sections. Hence, urgent need to create and implement a management plan to curb further spread in future. Further studies on how Lantana camara biomass can be anaerobically digested to produce biogas used for cooking and electricity generation will be of paramount importance. Also, oil extraction from Lantana camara seeds to produce biodiesel which is eco-friendly can be adopted. Restoration projects using indigenous trees is needed as I thoroughly observed that Lantana camara was absent under the indigenous tree canopies hence a control means.
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    Abundance of wild Nile tilapia (Oreochromis niloticus) around cages at source of the Nile fish farm: implication for disease transmission between farmed and wild fishes
    (Makerere University, 2022-12) Mayambala, Paddy
    Although tilapia culture in cage fish farming systems in Uganda presents a steady rise in growth the entire sector is a subject to the different emerging tilapiine diseases and pathogens which have so far been reported at different fish farms by farmers and researchers to cause significant stock depreciation through increased fish mortalities arising from disease and pathogen infestation to the cultured stocks. Currently, with the increased intensification, production and commercialization of the fish culture systems, there have markedly been increased concerns of rampant disease outbreaks among cultured tilapiine stocks pertaining the outbreak and emergence of bacterial, fungal and viral diseases as well as parasite infestation which has hindered investment, thus curtailing unimpeded production and extension of the sector. Despite the conducive tropical climate that favors fish farming in the tropics, limited, if any, focus has been invested as regards fish health and the subsequent biosecurity programs meant to protect fish from contracting infections therefore inferring increased disease infestation and hindered sector growth. Attention as pertains fish health and biosecurity measures have long been focused on the indirect modes of disease and pathogen transmission (transfer of infectious agents from reservoirs to the fish hosts by inanimate objects [e.g., vehicles and PPE], or animate intermediaries). Despite the practice of such measures to combat disease infestation onto the farmed stocks, the prevalence of diseases and pathogens is persistent thus farmers and researchers have still reported increased cases of disease outbreak among farmed fish stocks. However, the design, construction and positioning of the cages systems in water bodies infers to easily permit the interaction of wild and farmed fish stocks thus facilitating direct transmission of disease pathogens and parasites from the wild to the farmed fish stocks or vice versa. The results of this study validated that wild fish populations lied in proximities of fish cages and are capable of transmitting infectious agents to farmed tilapiine stocks or vice versa. Therefore, besides the indirect modes of transfer of infectious agents that are affirmed to attribute to the rampant disease prevalence amongst farmed tilapiines, the results of this study call for further interventions by researchers and farmers as regards prevention of direct disease and pathogen transfer modes between wild and farmed tilapiines. Finally, the review contains suggestions for future research that will fill gaps needed to effectively prevent, manage and combat rampant disease incidences on fish farms.
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    Accessibility, quality and competing uses of silver cyprinid (Rastrineobola argentea) from selected markets of Kampala and Masindi.
    (Makerere University, 2021-05-07) Mukimba, Sharon
    Silver cyprinid (Rastrineobola argentea) is a small pelagic fish with several competing uses, and ranks third of the top three commercial fish species landed from Lake Victoria. This study investigated the level of contaminants, competing uses and accessibility of silver cyprinid in two markets from Kampala (Kalerwe and Kibuye) and Masindi main market. In each of these markets, a 1.0 kg sample was picked from 18 traders, and analyzed for physical contaminants by sorting and weighing them using a weighing balance. Data were collected on origin, quantities of silver cyprinid received per week and uses. Data were collected using a questionnaire administered to individual traders. Physical contaminants included sand (0.05, 0.01 0.00) kg, mayflies (0.03, 0.016, 0.01) kg and snail shells (0.004, 0.02, 0.03) kg from Kalerwe, Kibuye and Masindi main markets respectively. Snail shells were most dominant than mayflies; Kampala markets obtained silver cyprinid from Lake Victoria (Kasenyi, Kiyindi and Kikondo) whereas Masindi main market received consignments from Lake Albert (Panyimur, Wanseko, Kabolwa). Kibuye and Kalerwe markets had sold larger quantities of silver cyprinid sold per week (i.e., about 1000 kg) than Masindi main market where 870 kg. Most of the purchased silver cyprinid was intended for human consumption (95.5% in Kalerwe, 94.4% in Kibuye and 96% in Masindi main market), the rest (4.5%, 5.6% and 3.9%) being for animal feed production. Over 90% of the silver cyprinid in Kampala and Masindi main markets is intended for human consumption. Less than5% of silver cyprinid in these markets is for animal feed production. The silver cyprinid sold in Kalerwe, Kibuye and Masindi main markets contains physical contaminants such as sand, mayflies and snail shells which deter it suitability for the intended uses (human consumption or animal feed production). The volumes of silver cyprinid purchased per week are higher in Kampala markets than in Masindi main market suggesting better accessibility in Kampala than Masindi. Therefore, quality control of silver cyprinid should be emphasized right from harvesting through processing to marketing, to ensure minimal quality deterioration. Fishers and processors of silver cyprinid need to be sensitized about the sources of contaminants and how they get into the fish during processing. Additionally, traders should set mechanisms to consistently demand for quality x silver cyprinid and probably reject adulterated products with sand, shells or mayflies. This approach will create feed back to the processors leasing to hygienic processing of the products. To sustain high proportion of silver cyprinid meant for human consumption, emphasis should be put on maintaining quality processing, handling and storage.
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    Accessing the suitable parameters for the production of carbonized briquettes using bagasse, clay as binder and molases as a filler.
    (Makerere university, 2022) Musiime, Ivan Bbala
    Sugar Coperation Of Uganda Limited SCOUL generates about 1.5 million tons of sugarcane bagasse per year which has enormous potential for exploitation in modern commercial applications. 0.8 tons of bagasse is used in the cogeneration process during the production of electricity leaving 0.7 tons of bagasse useless and an environmental hazard. Due to rising fossil fuel prices, availability in large quantity and rapidly growing interest in bio energy as well as technological advances and environmental concerns, bagasse could be utilized for the formulation of carbonized briquettes for household use to supplement wood charcoal. In this study briquettes were formulated using carbonized bagasse, clay as a binder and molasses as a filler. Bagasse was obtained from SCOUL for carbonization. Carbonization was carried out using a brick-built kiln while blending used a manually operated drum mixer at Josa Green Technologies in Wakiso District. A piston type briquetting press fitted onto a universal strength testing machine was used for the production of briquettes. The most optimum parameters that produced briquettes which complied with current charcoal specifications for household use were in the ratio of 1:1:40 for molasses, clay and carbonized bagasse respectively at 0.50N/mm2 pressure. At this formulation, briquettes were produced whose ash content, volatile matter and calorific energy were 36.4%, 27.2% and 4.390 Kca/g respectively. The briquettes produced burnt without sparks and were smokeless, producing no irritating smell. They ignited easily and took relatively long before they extinguished. They were recommended for household use in Uganda.  
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    Activated carbon derived from banana peels for the removal of cadmium ions from waste water in Nansana Municipality
    (Makerere University, 2024-06) Habaasa, Edgar
    This study was conducted to investigate the removal of cadmium (II) from aqueous solution by using low cost, natural and eco-friendly bio sorbent of Banana peels Activated Carbon (BPAC) through batch experiments. The Activated Carbon was characterized by FTIR, SEM, TEM with EDX. Various adsorption parameters such as effect of pH, amount of the biomass, initial concentration of Cadmium ion and contact time on the adsorption capacity of the bio sorbent were studied. Biosorption experiments were carried out at the temperature of 25ºC. The percent removal of Cadmium ions was 98.35% from synthetic wastewater. These results were observed at the optimum dose of 0.8 g at pH 4.0. The removal of Cadmium ions from wastewater is mainly influenced by pH of the synthetic wastewater and the amount of bio sorbent dose. The equilibrium adsorption data were fitted to Langmuir adsorption isotherm model and the model parameters were evaluated. The kinetic study showed that the pseudo-second order kinetic model better described the biosorption process. These results demonstrated that the Banana peels could be used as a natural bio sorbent for removal of cadmium (ii) ions from aqueous solution
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    The activity of CENTELLA ASIATICA extract against STAPHYLOCOCCUS Epidermidis.
    (Makerere University, 2022) Tukamushaba, Bruce
    Staphylococcus epidermidis with the highest percentage has the prominent role among coagulase-negative Staphylococci that is the most important reason of clinical infections and this is due to various virulence factors and unique features. Centella asiatica is a clonal herbaceous creeper belonging to the family Umbellifere (Apiceae) and is found mostly in moist places of tropical and subtropical countries where it is used as a traditional medicine, it contains active components such as; alkaloids, flavonoids, saponins, tannins and triterpenoids that give it it’s medicinal properties. Many studies have shown that the plant has several biological and pharmacological activities but there is no documentation of the result of the study of the activity of Centella asiatica extract against Staphylococcus epidermidis. The general objective of this study was to determine the activity of Centella asiatica ethanolic extract against Staphylococcus epidermidis. The activity of the ethanolic extract of Centella asiatica against Staphylococcus epidermidis ATCC 1228 was determined using the Agar well diffusion method and the experiment was done in triplicates using Vancomycin as the positive control and 4% DMSO as the negative control. The highest concentration of the ethanolic extract of Centella asiatica did not show any activity towards the Staphylococcus epidermidis ATCC 1228 and so did the negative control (4% DMSO), while the positive control (Vancomycin) showed a greater antibacterial activity against the test strain with a mean zone of inhibition of 27mm. A number of factors could have affected the activity of the ethanolic extract of Centella asiatica against Staphylococcus epidermidis ATCC1228 in this study. This study could be the beginning of further research on the activity of Centella asiatica extracts against Staphylococcus epidermidis by taking into consideration the extraction preparation, mechanism of action, antimicrobial assay and the other different parameters that could have affected this study.
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    Activity of Lantana camara and Aframomum angustifolium Streptococcus extracts on Pneumoniae and Klebsiella Pneumoniae.
    (Makerere University, 2021-04-23) Nakayima, Agnes
    The major aim of this study was to examine the invitro antimicrobial activity of Lantana camara and Aframomum angustifolium extracts on Streptococcus pneumoniae and Klebsiella pneumoniae. Streptococcus pneumoniae and Klebsiella pneumoniae are microorganisms responsible for pneumonia, an upper respiratory tract infection. Symptoms include: nasal obstruction, sore throat, tonsillitis, sinusitis and common cold. In Uganda (2015), 1.72 million cases of the infections were estimated to have occurred. Some bacteria strains have acquired antibiotic resistance therefore infections cannot be reliably treated. Antibiotics are beyond the reach of a common man since they are expensive therefore many people have resorted to the use of herbs without validation hence the need for scientific study of traditional plants with medicinal value. The two-study plant material were collected from Iganga and taken to Makerere herbarium for validation. The plant materials were cleaned, air dried and pulverized. crude compounds were extracted by maceration under ethanol. Extracts were concentrated by rotary evaporation. Agar well diffusion was used to determine the diameter of inhibition of the different plant part extracts against the bacteria on Muella-Hinton agar. Serial broth dilution was used to determine minimum inhibitory concentration of the plant extracts. Tests were carried in triplicates. The data obtained was analyzed using MS excel and the R package version Rx644.0.3. Two-way Anova was used to compare the different means(p<2e-16). This study shows that a combination Lantana camara and Aframomum angustifolium is a potential drug for the treatment of pneumonia infections. However, in low concentrations of 0.065g/l, there was no effect of plant extracts on the bacteria strains. Therefore, a combination of the two plant extracts can be used as effective drugs in high concentrations of 0.5g/ml. Individual plant extracts were more effective on Streptococcus pneumoniae than Klebsiella pneumoniae. There was a significant effect of each of the drug extracts in high concentration of 0.5g/ml on each of the bacteria strains.
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    Activity pattern and enclosure usage of black forest cobras (Naja melanoleuca) at Uganda Reptile Village (URV), Entebbe
    ( 2019-04) Kibuuka, Nelson
    This study was designed to investigate how the design of enclosures affects the activity budget of the forest cobras which have a very particular habitat choice and behavioral repertoire in the wild. Data was collected at Uganda Reptile Village on five forest cobras (Naja melanoleuca) of the same species to determine the overall daily activity patterns and usage of all available areas of their enclosure. Instantaneous scan sampling of the whole group of snakes during three periods each day (morning, midday and afternoon) allowed for changes in behaviour patterns to be assessed over time. Zone usage was analyzed using a modified Spread of Participation Index (SPI) and a Chi square test was used to analyze the data. The data revealed that the subjects did not use their enclosure evenly as some areas which provided resources were used significantly more than others. Significantly enhanced behavioral repertoires occurred in the “natural” zones of the enclosure and three grouped activity patterns (intense activity, moderate activity and inactivity) showed significant differences in performance between ‘natural’ and ‘artificial’ zones, and between times of day. Forest cobras spent approximately 40% of their time resting, 20% basking, 5% swimming and the remaining percentage feeding, vigilance and moving. Inactivity had a higher frequency than moderate and intense activity for the entire study time. The group spent around 60% of its time in only around 30% of the enclosure. Overall, enclosure design based on facets of natural ecology is important for the expression of a “wild-type” behaviour pattern in captive reptiles. This explains why forest cobras will actively choose biologically relevant areas of their enclosure. Therefore enclosure design has a profound influence on the behavioral activity budget and enclosure use of the snakes. It is suggested that alterations to reptile regime and management style of such specialized reptiles could help improve captive behavioral repertoires and enhance the display of such animals in captive facilities. The recommendation to improve enclosures for reptiles by providing ‘natural’ like zones is suggested which will make the enclosures mimic the wild habitats to ensure proper behaviour of the reptiles in ex-situ conservation.
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    Acute toxicity of Steganotaenia araliacea Hochst ethanolic stem-bark extract on winstar albino rats
    (Makerere University, 2025-11-28) MARTIN, MWIJUKYE
    Acute Oral Toxicity Evaluation of Ethanolic Stem-Bark Extract of Steganotaenia araliacea Hochst in Wistar Albino Rats Chronic kidney disease and acute kidney injury represent major public health challenges in Uganda and across Africa, where access to conventional renal-protective drugs remains limited and costly. Steganotaenia araliacea Hochst (Apiaceae), commonly known as the carrot tree, is widely used in Ugandan traditional medicine for various ailments, including as a diuretic, but its safety profile has not been scientifically established. The present study aimed to evaluate the acute oral toxicity of the ethanolic stem-bark extract of S. araliacea and to determine its median lethal dose (LD50) in Wistar albino rats. The extract was prepared by 96% ethanol maceration of shade-dried stem bark collected in Wakiso District, Uganda. Acute toxicity was assessed following OECD Guideline 425 (Up-and-Down Procedure). Male Wistar albino rats (200–220 g) received single oral doses of 2000 mg/kg or 5000 mg/kg body weight, with a concurrent vehicle control group. Animals were observed for 14 days for mortality, clinical signs, body weight changes, organ weights, gross pathology, and histopathology of liver, kidneys, and stomach. No mortality occurred at any dose up to the limit dose of 5000 mg/kg, resulting in an LD50 > 5000 mg/kg. Transient clinical signs (mild lethargy, increased respiration, abnormal defecation, and partial sleep) were observed within the first 24 hours but resolved completely. An initial body weight reduction was followed by full recovery and normal weight gain. Gross examination revealed no lesions, and organ-to-body weight ratios were comparable to controls. Histopathological analysis showed no significant alterations in liver or kidneys at either dose. Mild gastric epithelial sloughing was noted only at 5000 mg/kg, indicating localized irritation. The ethanolic stem-bark extract of Steganotaenia araliacea is practically non-toxic acutely when administered orally to rats (GHS Category 5 or unclassified). These findings provide the first preclinical safety data supporting the relative short-term safety of this traditionally used plant and lay the foundation for further sub-chronic toxicity, phytochemical, and efficacy studies targeting renal disorders.
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    Adaptive strategies of Nile Tilapia (Oreochromis Niloticus L.) to changing habitat
    (Makerere University, 2018-07-26) Akoth, Dorothy
    Environmental changes are some of the factors that affect fisheries and biological characteristics of fishes. The Nile tilapia has biological characteristics that enable it to continue existing under various stressful environmental conditions. However, limited studies have examined the influence of habitat shrinkage on the morphological parameters and feeding behaviour of the Nile tilapia. The study examined some of the biological characteristics of Nile tilapia in lakes Wamala and Victoria (Uganda) to provide an understanding of their response to changing habitat conditions due to climate variability and changes. A total of 64 archived specimens were used in the study. Diet data of O. niloticus from Lake Victoria was obtained from Njiru et al., 2008. The study observed significant morphological differences between Nile tilapia from the two lakes with specimens from Lake Victoria being larger than those from Lake Wamala. The eye depth, cheek depth, snout length, lower jaw length, lower jaw width and dorsal fin base length were the key morphological parameters that seemed to adjust faster to the changing environment. These differences were attributed either to genetic or environmental factors, which seemed to play a major role in influencing morphology of Nile tilapia populations. With regard to feeding, O. niloticus in both lakes are still phytoplanktivorous. Nonetheless, specimens from Lake Wamala have included more zooplankton and higher plant material whereas Lake Victoria dwelling specimens included insects and mollusks in the diet. The results reflect an adjustment to the available dietary components that occur in habitat specific conditions. Therefore, the Nile tilapia has the capacity to adjust appropriately under conditions created by climate variability and changes in order to adapt to such environments. Proper management of the fish species can sustain the fisheries of Lakes Wamala and Victoria.
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    Adsorption and corrosion inhibition properties of ricinus communisin acid solutions
    (Makerere University, 2024-10-31) Mukhwana, Felix
    The castor plant, with its potential phytochemical constituents, presents an opportunity to serve as a green corrosion inhibitor.This study aims to evaluate the adsorption and corrosion inhibition properties of castor plant extracts on mild steel in acidic media. Leaves of the castor oil plant were sun dried using both sunlight and an oven. The dried leaves were then ground to increase the surface area. Solvent extraction was carried out using ethanol as a solvent and filtered. The extract obtained in ethanol solvent was concentrated, distilling off the solvent. Solutions of the extract were prepared in the concentrations of (50,25,10) v/v per cent, with the respective corrodents as solvent that is 0.5M H2SO4 and 1M HCL. Weighed mild steel coupons were separately immersed in 250 mL open beakers containing 1.0 M HCl and 0.5 M H2SO4. Also, mild steel coupons were separately immersed in 250 mL open beakers containing 1.0 M HCl and 0.5M H2SO4 with various concentrations of the castor oil leaf extracts. After 4 hours the coupons were taken out, immersed in acetone, dried and reweighed. The weight loss was calculated as the difference between the initial weight and the weight after the removal of the corrosion product. The experimental readings were recorded to be used in calculating corrosion rate and the inhibition efficiencies The corrosion rate of mild steel decreased with increasing extract concentration in both acidic environments confirming the formation of a protective layer by the extract molecules on the steel surface. The gravimetric method revealed that the castor plant extract exhibited promising corrosion inhibition efficiency (IE) across different concentrations in both 0.5M H2SO4 and 1M HCl The effect of temperature on corrosion rates with and without the castor plant extract provided valuable insights into the adsorption behavior and potential mechanism of inhibition.
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    Adsorption behavior of amoxicillin and sulfamethoxazole antibiotics onto activated carbon antibiotics
    (Makerere University, 2020-12) Kemigisha, Nancy
    The ability of activated carbon to adsorb the antibiotics, amoxicillin and sulfamethoxazole from an aqueous solution was studied for batch experiments. The adsorption study was done for several variables as contact to e, adsorbate dosage and pH. It was found out that generally the adsorption rate increases with increase in contact time only up to a point when equilibrium is reached and the rate of adsorption equals the desorption rate in the aqueous solution at optimum time. Further increase in time causes no change in rate of adsorption. The rate was also found to increase with pH till an optimum pH after which the rate decreases. Increase in adsorbent dosage was also found to increase with the rate if adsorption till a maximum point after which the rate remains constant. The adsorption kinetics was studied for several adsorption isotherms that were found to always exist together but the favourability of one depends on the individual study parameters which are R for the Langmuir model and n for the Freundlich model
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    Adsorption of lead (II) ions from synthetic waste water using biochar derived from sugar cane bagasse
    (Makerere University, 2019-07) Ebwosu, Moses
    In this research, adsorption technique was applied for the removal of heavy metal i.e. lead and zinc in synthetic waste water. Biochar derived from sugarcane bagasse was preferred to any other materials because of its availability in Uganda. The objective of study was to investigate the removal efficiency of biochar derived from bagasse as an adsorbent for lead ions from synthetically prepared heavy metal concentrations. Adsorbents were prepared by pyrolysis of sugar cane bagasse, the biochar obtained was then ground into smaller particles. The waste water was prepared synthetically in the laboratory by dissolving metal solutions (lead nitrate) into deionized water. The prepared water was treated against the adsorbent with varying pH and adsorbent dosage using constant initial concentration of metals. The optimum pH was observed to be pH 7 for the maximum removal of lead ions. While the maximum efficiency for adsorption of biochar was 96.85% at its optimum PH of 7. The results obtained from the experiment were recorded and graphs were plotted to study the behavior of the adsorbent material in removing heavy metals from the water.
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    Adsorption of lead and different colors from waste water using coconut shells adsorbent in form of simple activated carbon
    (Makerere University, 2024) Kintu, Moses Edrine
    The activated carbon was prepared under limited supply of oxygen from coconut shells as the precursor.The coconut shells are the ones from coconut trees scientifically known as Cocos nucifera, L. Three different pyrolysis temperatures were considered with each three different soaking times investigated. Then also three different activation temperatures were used that is 650, 850 and 1250oC. The effect of the different activation conditions was investigated by comparing absorbance of Methylene blue in samples which had undergone the different conditions.The results strongly indicated that activated carbon used in this study were effective in removing methylene blue with a great reduction of colour and contact time to achieve equilibrium.
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    The adsorption of volatile organic compounds
    (Makerere University, 2021-03-24) Musamali, Margaret
    Volatile organic compounds (vocs) discharged into the environment cause negative and health hazards. In the recent years adsorption process has been employed to aid in the remediation process of VOC removal. In this project techniques such as adsorption process were employed in the removal of Volatile organic compounds an indoor pollutant at Global Paints Company Limited using activated coffee husks and wood Volatile organic compounds (VOCs) discharged into the environment cause negative and health hazards. In the recent years adsorption process has been employed to aid in the remediation process of VOC removal. In this project techniques such as adsorption process were employed in the removal of Volatile organic compounds an indoor pollutant at Global Paints Company Limited using activated coffee husks and wood as adsorbents. These VOCs arise from paint production process which includes the grinding of pigment, cleaning of the mixer tanks, blending and packaging of the finished paint product. The adsorbents used in the process were used because of their excellent adsorbability and are locally available in Uganda they are also highly efficient in removal of VOCs with a percentage removal ranging from 80%-100% . The main objective of this study was to determine the effectiveness and efficiency in the use of activated coffee husks and wood adsorbents in the adsorption process of VOCs. The adsorbents were activated by using physical (steam) and chemical activating agents (phosphoric acid) for wood and coffee husks respectively. The VOCs were obtained by taking 40g/m3 from a the vent connected to the batch mixing tank and then treated against two adsorbents of mass 250g/m3 at varying duration at constant temperature and pressure. The experimental data was obtained and breakthrough curves were drawn after the adsorption cycle to show how the outlet concentration varies with time and these provided a basis from which the breakthrough times can be obtained to show the time the adsorbent takes to permeate completely through the column. The curves were drawn in excel and the adsorption capacity for each VOC- activated carbon system was calculated to show the adsorption capacity of each activated carbon. From the experimental data it was noted that the best activated carbon system for the adsorption of the VOCs was coffee husks due to its high surface area to volume ratio and high macropore volume this offered greater adsorption capacity to the VOC compared to when using activated wood as an adsorbent. The breakthrough time represented the time it takes for the VOCs to be completely adsorbed by the adsorbent The break through time when activated coffee husks was used as an adsorbent on both acetone and dichloromethane was 140 minutes and 160 minutes respectively. The break through time when using activated wood as an adsorbent for both acetone and dichloromethane was 150minutes and 120 minutes. After wards recommendations to the company were given in relation to the activated carbon selected so that extensions to the batch mixer should be implemented inorder to capture any VOC produced during the process manufacture steps this xi would both improve the working conditions of the workers and the state of the ecological systemas adsorbents. These vocs arise from paint production process which includes the grinding of pigment, cleaning of the mixer tanks, blending and packaging of the finished paint product. The adsorbents used in the process were used because of their excellent adsorbability and are locally available in Uganda they are also highly efficient in removal of vocs with a percentage removal ranging from 80. The main objective of this study was to determine the effectiveness and efficiency in the use of activated coffee husks and wood adsorbents in the adsorption process of vocs. The adsorbents were activated by using physical (steam) and chemical activating agents (phosphoric acid) for wood and coffee husks respectively. The vocs were obtained by taking 40g/m3 from a the vent connected to the batch mixing tank and then treated against two adsorbents of mass 250g/m3 at varying duration at constant temperature and pressure. The experimental data was obtained and breakthrough curves were drawn after the adsorption cycle to show how the outlet concentration varies with time and these provided a basis from which the breakthrough times can be obtained to show the time the adsorbent takes to permeate completely through the column. The curves were drawn in excel and the adsorption capacity for each VOC- activated carbon system was calculated to show the adsorption capacity of each activated carbon. From the experimental data it was noted that the best activated carbon system for the adsorption of the vocs was coffee husks due to its high surface area to volume ratio and high macropore volume this offered greater adsorption capacity to the VOC compared to when using activated wood as an adsorbent. The breakthrough time represented the time it takes for the vocs to be completely adsorbed by the adsorbent The break through time when activated coffee husks was used as an adsorbent on both acetone and dichloromethane was 140 minutes and 160 minutes respectively. The break through time when using activated wood as an adsorbent for both acetone and dichloromethane was 150minutes and 120 minutes. After wards recommendations to the company were given in relation to the activated carbon selected so that extensions to the batch mixer should be implemented in order to capture any VOC produced during the process manufacture steps this xi would both improve the working conditions of the workers and the state of the ecological system0g/m3 at
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    Aeration optimization of the waste water treatment at hariss international effluent treatment plant in tula-kawempe.
    (Makerere University., 2023-08-05) Ongu, Emmanuel
    Aeration systems often consume a significant portion of the total energy utilized in wastewater treatment plants (WWTPs). Therefore, optimizing the aeration process is essential to improve overall plant efficiency, reduce operational costs, and minimize environmental impact. In this study, the wastewater parameters (COD, TSS, TDS and Total Nitrogen) were obtained from Hariss International Ltd Effluent Treatment Plant with the assistance and supervision of the employee in-charge. The results were obtained in a full-scale bioreactor located at the Hariss International Limited WWTP, where a nitrogen removal based on a nitrification–denitrification process was being tested. It has been shown that the crucial parameter to ensure a complete removal of COD and nitrogen was to give the system a long time of on–off aeration to complete both the nitrification and the denitrification processes, The wastewater parameters obtained were fed in a simulation run such that the obtained results were being tested again in the WWTP. The industrial data used to perform the analysis was obtained from Hariss International Limited wastewater treatment plant located In Kawempe along Mperewe-Tula road and hence the corresponding data is collected from the plant. Data includes influent flow rate, influent pollutants, effluent pollutants, and aeration process parameters. The effluent quality parameters were determined using the available methods used at the plant. The experiment was majorly hands on and also computational efforts applied. It was observed that the Effluent Quality (EQ) index was decreasing as the number of cycle increased. Using 6 cycles a day (i.e. 6 air-on and 6 air-off periods) an effluent load of 426 kg/d and an aeration energy consumption of 541kWh/d was reached. Increasing the number of cycles up to 12 per day, the effluent load reduced to 408 kg/d while the energy consumption of the aeration also decreased somewhat, down to 501 kWh/d. In conclusion, In order to validate the results achieved with this optimization method, further investigations should be carried out both for pilot-scale and full-scale treatment plants.