College of Natural and Computational Sciences
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College of Natural and Computational Sciences
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Item COMMON BEST PROXIMITY POINT RESULTS FOR MULTI-VALUED CYCLIC MAPPINGS ON PARTIAL METRIC SPACES(wolkite University, 2025-02-28) AZIZEW ABATEThis thesis investigates best proximity point theory as a natural generalization of classical fixed point results to non-self mappings. The study focuses on generalized (α,T)-contraction mappings, cyclic and multi-valued in partial metric spaces. By unifying concepts from Hausdorff metric space and partial metric spaces, we develop existence and uniqueness theorems for best proximity points under various contractive conditions. The results extend the principle to provide new insights into cyclic and multi-valued mappings. Illustrative examples are presented to verify the applicability of the findingsItem DIET COMPOSITION AND FEEDING HABITS OF CYPRINUS CARPIO (LINNAEUS 1758) (PISCES: CYPRINIDAE)(Wolkite University, 2024-11-01) INJIGU WENDIMUThe diet composition and feeding habits of Cyprinus carpio (Linnaeus, 1758) were examined using 209 fish samples from Lake Arekit. The species' feeding patterns were determined through numerical indexes (frequency of occurrence and volumetric contribution) and composite indexes (Index of Preponderance (IOP) and Geometric Index of Importance (GIIi)). Among the 209 specimens, 174 (83.3%) displayed a range of dietary items in their stomachs. Detritus emerged as the primary food source for C. carpio, followed by macrophytes, insects, and zooplankton. A lesser amount of phytoplankton, nematodes, and ostracods were also consumed. Based on the findings, C. carpio can be classified as a detri-omnivore, as it consumes benthic species like nematodes, ostracods, and insect larvae. Seasonal fluctuations in food item consumption were noted (p < 0.05), with higher intake during the rainy season and reduced consumption in the dry season. Significant variations in food preferences were observed among size groups (p < 0.05). Smaller size classes preferred foods of animal origin, such as ostracods, zooplankton, and insects, while macrophytes and detritus were more prevalent in the largest class. This study enhances our understanding of C. carpio's diet in Lake Arekit. Still, further research is necessary to explore the diet across the fish's lifespan and monthly, considering various environmental conditions.Item College of Natural and Computational Sciences Department of Biology Ethnobotanical Study of `Medicinal Plants Used by Indigenous People of Munesa District(Wolkite University, 2024-12-01) Getu HirpoEthno botany is the scientific study of the way that people used plants to treat different human and livestock diseases. It includes all studies that concern with the mutual relationship between plants and people.The main objective of this study was to assess the traditional medicinal plants used by the indigenous people in selected kebeles of Munesa district. Traditional medicine is used throughout the world as it is dependent on locally available plants, which are easily accessible and capitalizes on traditional wisdom repository of knowledge simple to use and affordabily. Structured questionnaire, interview, observation, and document reviews were employed to collect both primary and secondary data. The data was analyzed and presented in qualitative and quantitative methods in that Paired comparison, fidelity level, preference ranking, informant consensus factor and direct matrix ranking were used during data analysis Medicinal healers of the study area gave treatment for different human and livestock diseases like: conjure, breast disease, snake bite, liver diseases, diabetic, cold sore, throat infections, sexually inactive male, allergy, epilepsy, antiseptics, diarrhea, bloat, endo and ecto parasite, Helminthiasis, Anthrax and others. The traditional healers prepare the traditional medicine by mechanisms like: crushing/grinding, squeezing, boiling, roasting. They used different route of administration such as: oral, tying, fitted to the target infected site by traditionally standardized dose. Leaf/pod and root/rhizome were highly used by more than half of the respondents (27%, 26% respectively) for the preparation of traditional medicine. The findings of this study showed that, many of effective medicinal plants in the study area were under risk of threatening or they endangered and any concerned body can give attention for conservation of these threatened medicinal plant species.Item Green Synthesis of Fe-doped zinc oxide Nanoparticle for Removal of Methylene blue dye from Aqueous Solution(Wolkite University, 2025-01-10) Wondimlebesku Delelegn HaileIn this study, Zinc oxide (ZnO) and iron-doped zinc oxide (Fe-doped ZnO) nanoparticles were synthesized using a green sol–gel method, utilizing Justicia Adhatoda plant leaf extract as a reducing agent. The aim was to investigate the potential of these nanoparticles as adsorbents for the removal of methylene blue dye, a toxic effluent commonly found in wastewater from textile industries. The synthesized materials were thoroughly characterized using various techniques: X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and UV-visible (UV-VIS) spectroscopy. XRD analysis confirmed that both ZnO and Fe-doped ZnO nanoparticles exhibited a hexagonal wurtzite crystal structure, with good crystallinity and phase purity. The average particle sizes were found to be 24 nm for pure ZnO and 20 nm for Fe-doped ZnO, indicating that doping with iron slightly reduced the particle size. FT-IR analysis revealed key absorbance peaks corresponding to functional groups from the plant extract, confirming the involvement of the plant's organic compounds in the nanoparticle synthesis. The UV-VIS results showed a shift in the absorption spectra of Fe-doped ZnO nanoparticles, with the maximum absorption wavelength moving from the ultraviolet (UV) region to the visible range, indicating enhanced optical properties due to iron doping. The adsorption performance of the ZnO and Fe-doped ZnO nanoparticles was evaluated under various conditions. The optimum removal efficiency for ZnO nanoparticles was achieved at pH 9, with an adsorbent dose of 20 mg, a contact time of 45 minutes, and an initial dye concentration of 5 mg/L, resulting in a dye removal efficiency of 95.23%. For Fe-doped ZnO nanoparticles, the same conditions led to a higher removal efficiency of 99.52%. The adsorption kinetics followed the pseudo-second-order model, suggesting chemisorption as the primary mechanism of dye removal. Furthermore, the study demonstrated the recyclability of the synthesized nanocomposites, showing that they could be effectively used for more than five cycles without significant loss in efficiency. These findings suggest that the green-synthesized ZnO and Fe-doped ZnO nanoparticles are promising, eco-friendly adsorbent materials for wastewater treatment, particularly for removing hazardous dyes like methylene blue, and could be applied in sustainable, cyclic water purification processes.Item GREEN SYNTHESIS OF PANI/MAGNETITE ADSORBENT USING CROT ON MACROSTACHYUS LEAF EXTRACT FOR REMOVAL OF RHODAMI NE BLUE DYE FROM AQUEOUS SOLUTION.(Wolkite University, 2025-01-01) YESHIWAS DAGNAW YEWALAIn this study, a green synthesis approach was employed to create adsorbent consisting of polyaniline (PANI) and magnetite (Fe₃O₄) nanoparticles using an aqueous extract of Croton macrostachyus leaves. To characterize the structural, chemical, and optical properties of the synthesized materials, several analytical techniques were employed. The XRD results indicated that the average particle size of the PANI/Fe₃O₄ adsorbent was approximately 14 nm, suggesting that the material consisted of nanoscale particles, which is crucial for improving the surface area and reactivity of the adsorbent. UV-DRS analysis revealed that the nanocomposite exhibited broad absorbance peaks between 700 and 800 nm. FTIR spectroscopy confirmed the presence of functional groups corresponding to PANI/Fe₃O₄, PANI and Fe₃O₄, and the phytochemicals in the Croton macrostachyus leaf extract. The adsorptive efficiency of each material was evaluated under varying experimental conditions, such as pH, adsorbent dose, contact time, and initial dye concentration. The results showed that the optimum conditions for dye removal occurred at a pH of 10, an adsorbent dose of 80 mg, a contact time of 50 minutes, and an initial dye concentration of 10 mg/L. Under these conditions, the dye removal efficiencies were 91.22% for PANI, 96.97% for Fe₃O₄, and 99.91% for the PANI/Fe₃O₄ adsorbent, demonstrating exhibited superior dye removal performance. To further understand the adsorption behavior, adsorption isotherm models were applied. The results indicated that the adsorption of Rhodamine Blue dye onto all three adsorbents (PANI, Fe₃O₄, and the nanocomposite) was best described by the Langmuir isotherm, suggesting that the adsorption occurred via a monolayer adsorption process with uniform adsorption sites. In contrast, the Freundlich isotherm, which models heterogeneous adsorption, did not fit as well, indicating that the adsorption sites on the materials were relatively uniform. Additionally, the adsorption kinetics were found to follow the pseudo-second-order model, suggesting that the rate-limiting step of the dye removal process was chemical adsorption. The findings from this study underscore the potential of the green-synthesized PANI/Fe₃O₄ adsorbent as a highly effective and environmentally friendly adsorbent for the removal of organic dyes from wastewater.Item THE IMPACT OF PRACTICAL LEARNING ON STUDENTS ACHIEVEMENT IN CHEMISTRY. THE CASE OF ADELE SECONDARY SCHOOL(Wolkite University, 2025-09-01) MULUGETA GOSSAYE TEKAThe purpose of this study was to investigate the impact of practical work in enhancing students’ achievements in chemistry in Adele secondary school particularly in grade 10, Sodo Woreda East Gurage zone, Centeral Ethiopia. To achieve this objective i.e. to examine impact of practical learning on students’ performance in chemistry, and on the students attitude toward chemistry; this study was employed quasi-experimental design. among a total of six targets secondary school in Sodo Woreda Adele secondary school was selected purposively. 80 students as a sample size out of 600 total populations were selected by using random sampling method. To keep the proportional allocation of students from each section, stratified sampling technique was used. The sampled students were placed in to two groups; experimental group and control group. Both the groups were exposed to the pre-test. The experimental groups were taught using the practical approach for eight week while the control groups were taught using the conventional method. The study used three instruments namely chemistry achievement tests, students’ attitude questionnaires and observation checklists were used as a data collection tools. at the beginning of the first week, both groups give the pre-test chemistry achievements and the post-test achievements test at the end of the eight week. The data obtained were analyzed using SPSS version 20. T-test was used to test the statistical significance in the hypothesis generated in the study. The significance of the results was tested at α = .05 significance level. The findings othe students showed that practical approach resulted in higher students’ achievements in chemistry and lead to improved students’ attitude towards chemistry. The study concluded that, practical instructional approach towards chemistry is an effective teaching method which chemistry teachers should be encouraged to use to enhance students’ achievements in the subject. The study recommended adoption of the practical teaching approach in order to enhance students’ achievements and improve students’ attitude towards the subject.Item Green Synthesis and Characterization of Magnetite (Fe3O4) nanoparticle using Khat (Catha edulis) plant leaf extract for the removal of methylene blue dye from aqueous solution(Wolkite University, 2025-01-01) Metaalem ShibabawThis study synthesized magnetite nanoparticles using an aqueous extract of Catha edulis leaf in a green manner. The effectiveness and ability of the resultant nanoparticles in removing Methylene Blue dye were also assessed. Utilizing SEM, FTIR, P-XRD, and UV-DRS spectroscopy, the produced nanoparticle was examined. According to the XRD data, the average particle size of the produced magnetite NPs was 9.05 nm. The outcome confirmed that Fe3O4 nanoparticles had absorbance maxima at 364 nm, and for samples of produced magnetite nanoparticles, various functional groups were discovered to be connected with the plant extract. The produced Fe3O4 NPs displayed a variety of morphologies and microstructural features for Fe3O4 nanopowder. In addition, the SEM images of the Fe3O4 NPs showed that the nanoparticle morphology was uniform in structure. Using the batch adsorption method, the effectiveness of the adsorbent was assessed by adjusting several parameters, including pH (3–9), adsorbent dose (20–80 mg), initial adsorbate concentration (5 mg/L–20 mg/L), and room temperature contact time (30–90 minute). Optimal removal (99.25%) was achieved at pH 9, using 20 mg of adsorbent, 50-minute contact time, and an initial methylene blue concentration of 5 mg/L. The Langmuir isotherm model and pseudo-second-order kinetics model best described the experimental data (R² ≈ 1). This research suggests that the biosynthesized Fe₃O₄ nanoparticles show significant potential in the removal of methylene blue dye from aqueous solutions.Item DENTIFYING AND MINIMIZING STUDENTS’ MISCONCEPTIONS IN CHEMICAL BONDING: THE CASE OF GRADE 9 STUDENTS IN KUTERE SECONDARY SCHOOL, SILTE ZONE, CENTRAL ETHIOPIA, ETHIOPIATHE CASE OF GRADE 9 STUDENTS IN KUTERE SECONDARY SCHOOL(Wolkite University, 2024-09-01) HASSEN MAHMUD ALIChildren do not come to school as a “tabula rasa, but rather with knowledge gained from different sources and through daily life. These different sources can help or hinder learning. This situation is said to be misconception. The main purpose of this study was to identify and minimize students’ misconceptions about chemical bonding. The study was carried out in Kutere Secondary School in Silte Zone, Central Ethiopia with special reference to grade 9 students’ focus. Descriptive survey, especially a case study was employed to address the problem. To conduct this study 72 students were selected through stratified sampling technique from the total population of 360 students. To achieve the objectives of the study employed data gathering tools were the conceptual understanding tests (pre-and post-test) in the chemical bonding topic. Each question in the conceptual understanding test was designed to previous students’ knowledge and understanding about chemical bonding. All data collected were analyzed quantitatively. The study described the causes for these misconceptions. These were students’ personal experience, inappropriate use of laboratory, misinformation, inattentiveness, selective attention, and unevaluated text books. Replacing those misconceptions with scientifically accepted conceptual views is necessary and efforts should be made to create awareness continuously for students, teachers, school principals and educational experts. Conducting training and different workshop with those concerned bodies is more advisable to increase the understanding and to avoid (minimize) misconceptions in chemical bonding. Thus, to improve the situation, it is recommended that every educator should be aware of students background, daily life experience, pre conceptions before providing lessons on chemistry teachers should spend more time to produce more conceptual talk about the topic to bring conceptual understanding, different instructional methods should be applied to support conceptual understanding of chemical bonding.Item A CASE STUDY AT BURKA SEBETA 10 TH GRADE AND BURKA, SEBETA 12TH GRADE SECONDARY SCHOOL AT SEBETA SUBCITY SHEGER CITY OROMIA ETHIOPIA.(Wolkite University, 2024-05-01) BACHA DEBELE CHALAChemical bonding is a topic that students commonly find abstract and problematic and for which they develop a wide range of misconceptions . Thus, chemical bonding is considered as difficult topic and students had misconception about bond polarity, intermolecular force, intramolecular force, the octet rule, conductivity, Solubility shapes and lattice energy. The purpose of this study was to identify the major misconceptions of grade 12 and 10 students’ on the chemical bonding and to identify the sources of these misconceptions. The nature of the study is a descriptive method. Participants of the study were 67 grade 12 students and 75 grade 10 students. The FTMCT was developed after their prior conceptions about the selected topics of the study were collected from students through review of related literature, observation of lessons on chemical bonding, common mistakes of focus class students during different assessment techniques (answering class tests) and individual interview questions with volunteer students. Data was collected by using FTMCT and Interview questions were employed to gather the relevant data. Data was analyzed by using Statistical Package for the Social Science program (SPSS). The results from SPSS (bivariate and reliability analysis) showed that average value of reliability coefficient and correlation between 1 st tier and 2nd tiers, 3 rd tiers and 4 th tiers, 2nd tier and 4 th tier were .99, .75, .68, .67 of grade 12 students and .96, .73, .79, .74, of grade10 student respectively. The significances also shown that chemistry daily experiences, text books, language difficulty and chemistry instructional methods were the major source of students’ misconception about chemical bonding. The result showed that the majority of the students had high level of misconceptions about chemical bonding. In this study the common misconceptions were identified on chemical boding which was categorized into: bond polarity, solubility, intermolecular force, intramolecular force, the octet rule, shapes, conductivity and lattice energy.Item OPTICAL PROPERTIES OF SMALL SPHERICAL PURE METAL IN PASSIVE AND ACTIVE HOST MATRICES(Wolkite University, 2021-12-17) Girma Berga KeretaIn this thesis, we have studied the optical properties of small spherical pure metal in active and passive host matrix. One of the optical properties we have investigated by this work is the local eld enhancement factor for small spherical pure metal in passive and active host matrix. The results show that for small spherical pure metal there is only one maxima of the local eld enhancement factor in both the passive and active host matrix. We present an analytical and numerical method for optical bistability of small spherical pure metal in passive and active host matrix. Using the derived analytical and numerical results we calculated the cubic equation of the optical bistability of small spherical pure metal embedded in passive and active host matrix. To observe considerable di erences on the onset and o set parts of the plots of optical bistability for the active host matrix, we took the integer multiples for the imaginary part of dielectric function of the host matrix ( ′′ h), (i.e. ′′ h = −2, ′′ h = −3 and ′′ h = −4). The third main target of study was to derive the analytical and numerical results of the real and imaginary parts of refractive indices for small spherical pure metal embedded in a host matrix. We have plotted the graphs of the real and imaginary parts of the refractive indices of the analytical and numerical results for small spherical pure metal in active and passive host matrix. The numerical and analytical results show that the local eld enhancement factor is extremely enhanced, the optical bistability activation and the real and imaginary parts of the refactive index are increased when the small spherical pure metal is embedded in active host matrix (i.e. the natural or original property of the imaginary part of the dilectric function of the host matrix is a ected by applying additionalexternal dilectric function on the host matrix).