Browsing by Author "Kapolo, Paulus"

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    Effectiveness of higher order thinking scaffolding tool as a knowledge transfer instrument among University of Namibia science students
    (University of Namibia, 2017) Kapolo, Paulus; Sheimemanya, Cornelia; Shihomeka, Sadrag P.; Nghuumbwa, Malakia
    This paper presents the results of the study carried out at the University of Namibia on the extent to which high order thinking scaffolding tool can assist students to transfer knowledge. To examine the tool, a quasi-experimental design within the flipped-classroom was used in a mixed method study. Students were divided into two groups, the experimental group and the control group. These two groups were all approached in the similar manner and directed at different times of the day. The only difference was that the experimental group was provided with a scaffolding tool, while the control group had no scaffolding tool. The objective of the study was to evaluate the effectiveness of the Higher Order Thinking as a scaffolding tool that can improve students’ knowledge transfer. When the means were compared, it was found that there is no statistical significant difference between the two means for the Higher Order Thinking Tool group (M= 4.89) and the control group (M= 4.27),
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    Exploring grade 11-12 teachers’ use of instructional videos in natural science subjects at Ponhofi Secondary School
    (International Journal of Arts and Social Science, 2023) Nghuumbwa, Malakia; Shaimemanya, Cornelia Ndahambelela S.; Shihomeka, Sadrag P.; Kapolo, Paulus
    This study explored Grade 11-12 teachers’ use of instructional videos in Natural Science subjects at Ponhofi Secondary School in Namibia. To explore the attitudes, perceptions and experiences of teachers’ use of instructional videos, 8 semi-structured interviews (pre and post) were conducted. The pre-semi structured interviews were about the teachers’ attitudes, perceptions and experiences and were held with individual teachers before the teaching intervention using instructional videos. After the intervention, the post semi-structured interviews were conducted with the same individual teachers to assess their attitudes, perceptions and experiences after the use of instructional videos. The findings revealed that most of the teachers perceive instructional videos as powerful tools to teach Natural Science subjects and good for the learners’ subject mastery. The results further showed that most of the teachers lack self-confidence and have a high level of technophobia. It also emerged that there are a lot of barriers that affect teachers’ ability to use instructional videos such as technology resources, technology support, knowledge and skills and these barriers negatively affect the use of technology in schools and prevent teachers from becoming frequent technology-users. Finally, the findings revealed that, most of the teachers use free downloadable videos from various websites such as Eureka, Make Me Genius, Smart Learning for All and YouTube. The study concluded that teachers should adopt the culture of using instructional videos in their lessons to make their lessons informative, interesting, and resourceful and enhance understanding, and knowledge retention
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    The production of activated carbon from Acacia erioloba seedpods via phosphoric acid activation method for the removal of methylene blue from water.
    (Elsevier, 2023) Rahman, Ateeq; Hamushembe, Mirjam N.; Kapolo, Paulus; Daniel, Likius S.; Uahengo, Veikko; Jonnalagadda, Sreekantha B.
    Wastewater treatment requires a lot of granular activated carbon to absorb the dissolved organic components. This article describes a low-cost process for making highly active adsorption activated carbons from biomass, which could be used for wastewater treatment. A one-step carbonization and chemical activation with phosphoric acid at 500 ◦C produced low-cost acacia-derived porous activated carbons. The activated carbons’ moisture, ash, volatile matter, and fixed carbon content were determined using proximate analysis. The activated carbon’s adsorption qualities were also determined by studying its bulk density, surface morphology, power of hydrogen, iodine number, and methylene blue number index. To test the produced activated carbons for water treatment, batch adsorption dynamics were performed at room temperature for the removal of methylene blue from aqueous solution. Compared to activation using H2SO4, H3PO4 proves superior in generating welldeveloped pores, leading to a mesoporosity and microporosity structure with a larger surface area and high adsorption capacity. Brunauer–Emmett–Teller determined the sample’s specific surface area, which was found to be 387 m2 /g. The iodine number for 50, 100, and 200 μm activated carbon particles size was 620, 592, and 632 mg/g, respectively. The adsorption of MB on AC material better fits with Langmuir’s adsorption isotherm; hence, particles are adsorbed on well-pronounced heterogeneous surfaces. The sips model is found to best represent the equilibrium data with R2 values of 0.994, suggesting the heterogeneous surface adsorption of MB on AC. Therefore, the adsorption of AC by MB involves physical and chemical processes. The produced AC hence appears to remove dissolved organic contaminants from raw water.