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  Subjects -> SCIENCES: COMPREHENSIVE WORKS (Total: 374 journals)
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Ethiopian Journal of Sciences and Sustainable Development
Number of Followers: 0  

  This is an Open Access Journal Open Access journal
ISSN (Print) 1998-0531 - ISSN (Online) 2663-3205
Published by Adama Science and Technology University Homepage  [1 journal]
  • Experimental Investigation on the Effect of Teff Straw Fiber and Lime on
           Strength and Compressibility of Black Cotton Soil

    • Authors: Sifan Teshome, yadeta Chemdesa Chemeda
      Pages: 1 - 8
      Abstract: Black cotton soils often do not meet the geotechnical requirement as they exhibit high swelling-shrinkage behavior and compressibility. Therefore, stabilization of such soils with different additives is a common practice in geotechnical engineering. On the other hand, replacing traditional stabilizers with industrial and agricultural by-products has both economic and environmental significance. In this work, the effect of teff straw fiber, which is one of the common agricultural by-products in Ethiopia, on strength and compressibility characteristics of black cotton soil, was investigated. The combined effect of fiber reinforcement and lime treatment was also investigated. The black cotton soil sample was collected from Sendafa town. Samples of soil reinforced with various contents (0%, 0.5%, 0.75%, and 1% by weight) and lengths (20mm, 40mm, and 60mm) of teff straw fibers and mixed with various percentages of lime (2%, 4%, and 6%) were prepared to conduct compaction test, unconfined compressive strength (UCS) test, and consolidation test. The result showed that maximum dry density (MDD) decreased and optimum moisture content (OMC) increased with increasing both fiber and lime percent, while USC increased until 0.75% for teff straw fiber with each length and 4% (optimum %) of lime. The strength increased by more than double when the soil is reinforced with optimum percentage (0.75%) of fiber content and treated with lime (4%) as compared to when the soil is stabilized by lime (4%) only. Similarly, fiber reinforcement and lime stabilization significantly reduced the compressibility and swelling potential of soil. The finding of the work suggests that a combination of fiber reinforcement and lime stabilization is more effective for ground improvement than lime stabilization or fiber reinforcement alone.
      PubDate: 2022-07-18
      DOI: 10.20372/ejssdastu:v9.i2.2022.479
      Issue No: Vol. 9, No. 2 (2022)
       
  • Nuclear Science and Technology as a Part of Ethiopia‚Äôs Energy Mix and
           Sustainable Development Strategies: exploring opportunities and challenges
           

    • Authors: Girma Kibatu Berihie
      Pages: 9 - 18
      Abstract: Ethiopia is implementing a ten-year perspective plan (TYPP 2021-2030) with multi-layered activities that would enhance the capacity of the nation in science, technology, and innovation and effective application to economic transformation. While the country is endowed with many untapped natural resources and opportunities in using different areas of science and technology for development, its socio-economic development is not satisfactory. The current Ethiopian government as a part of its multi-layered activities in the TYPP has recently decided and launched a nuclear power program (NPP) to use nuclear science and technology applications in its energy mix and sustainable development strategies and is preparing infrastructures for its effective implementation. This paper provides a review of the role of nuclear science and technology in energy production and sustainable development; and analyses the status, challenges, and issues in the Ethiopian national nuclear program. The review sets out to discuss the main issues in a national nuclear program, nuclear energy management, and nuclear knowledge management demands and strategies for its effective application. Knowledgeable commitment to the nuclear science and technology program in developing countries like Ethiopia can boost economic growth. 
      PubDate: 2022-07-29
      DOI: 10.20372/ejssdastu:v9.i2.2022.471
      Issue No: Vol. 9, No. 2 (2022)
       
  • Extraction and Characterization of Oil from Moringa Stenopetala Seed

    • Authors: Gemechu Yadeta Shage
      Pages: 19 - 25
      Abstract: This study investigated the extraction and characterization of oil from moringa stenopetala seed oil. Oil was extracted using soxhlet extraction method at temperatures of 70 °c, 75 °c and 80 °c. The extraction time varied from 3 hours to 5 hours and the sample sieve size varied from 0.75 mm to 1.5 mm. Hexane was the solvent used for the extraction. The experimental result showed that the maximum oil yield was obtained at optimum process conditions of; temperature 80 °c, extraction time 5 hours and sample mesh size of 0.75 mm. The highest oil yield obtained was 39.86 %. This result agreed with the average oil content of moringa stenopetala which is 35 % to 45 %. Experimental data was analyzed by Box Behnken design method and the significance of experimental results were determined from analysis of variance (ANOVA).The main physicochemical properties of oil were determined according to international ASTM and EN standards. It was found that pure extracted moringa stenopetala oil has moisture content 6.54 %, pH 6.7, specific gravity 0.84 g/mole, kinematic viscosity 9.4 mm2/s ,acid value 1.6 mg KOH/g, saponification value 189 mg KOH/g,  free fatty acid 0.8 % and molecular weight of 895.5 g/mol. These results agreed with international standards values and previous works
      PubDate: 2022-07-29
      DOI: 10.20372/ejssdastu:v9.i2.2022.393
      Issue No: Vol. 9, No. 2 (2022)
       
  • DEGREE OF ACIDITY RELATED SOIL CHEMICAL PROPERTIES AND EFFECT OF LIME
           RATES ON P-ADSORPTION CHARACTERISTICS OF WAYU TUKA DISTRICT, WESTERN
           OROMIA, ETHIOPIA

    • Authors: Achalu Chimdi YARIMO
      Pages: 26 - 36
      Abstract: ABSTRACT Soil acidification and Phosphorus deficiency are major challenges to acid sensitive crop production in most of the highlands of Oromia. Study was initiated to evaluate degree of acidity related soil chemical properties and impact of lime (0, 3, 5, 7 and 9 t ha-1) rates on P sorption characteristics of acidic soil. Analysis of soil chemical properties (pH, exchangeable acidity, Aluminum saturation, available and total P, soil P-sorption characteristics and 90 days Greenhouse incubation were employed using standard laboratory procedures to evaluate effect of lime rates on acidity related chemical properties, P-sorption characteristics and percent increment of available p before and after incubation.  Result of soil pH, revealed that all soils from studied sties fallen in very strongly acidic (4.63-4.89) media. Values of soil exchangeable acidity, percent acid saturation and Al saturation of soils ranged from 1.43-2.49cmol (+) kg-1 soil, 5.36-9.37% and 3.57-6.28%, respectively. Available P before liming varied from 7.07-8.02 ppm and qualifying low range. However, due to application of lime, there was decrease of average percent total p- sorption of soils and ranged from 93% in the control to 57% at 9 t ha-1 lime rates. Moreover, percent increment of average available P ranges from 7.2% in the control to 43.6% for 9 t ha-1 lime. The positive values of R2 values of Langmuir regression equation indicated, there was strong positive relationship of increment of P availability with lime rates incubated soils. Therefore, attention shall be given to restore continuous cultivation of acidic soils of study sites using reclamation options.
      PubDate: 2022-07-29
      DOI: 10.20372/ejssdastu:v9.i2.2022.424
      Issue No: Vol. 9, No. 2 (2022)
       
  • Assessment of Spare part Sourcing and Recycling Activities Impact on the
           Availability of Lead, Cadmium and Total Petroleum Hydrocarbon in Evbareke
           Spare Parts Market Soil in Benin City, Nigeria

    • Authors: Okponmwense Moses, Ukeme Donatus Archibong
      Pages: 37 - 45
      Abstract: Recycling of spare parts obtained from dismantled unserviceable automobiles may be economical, however, it contributes to environmental degradation. The research was aimed at assessing the soil contamination intensity at Evbareke spare parts market automobile disassembling site. soil sample collection was separately pull together from top soil (0-20 cm) at automobile disassembling location and Evbareke senior secondary school serving as a reference/control site, using grid sampling method. The soil contamination level assessment index used include: relative pollution potential of the metals (RPP), single pollution index (SPI), geo-accumulation index (Igeo), average pollution index (API), total soil contamination index (TSCI) and pollution load index (PLI). The assessment was done with reference to data obtained from the control site soil as geochemical background value (CB). The contaminated soil particle size was categorized as loamy sand with coarse texture. The contaminated site soil had high total organic carbon content (TOC) due to high value of the total petroleum hydrocarbon (TPH) (107,304.59 mg/kg). Lead and cadmium content in the geochemical fractionation of contaminated soil was more than that in reference site soil, due to human influenced contamination. RPP value revealed that the soil was contaminated at the impact point with lead and cadmium. The soil from the contaminated site soil was excessively contaminated with lead (37.11) and slightly contaminated with cadmium (1.57) based on SPI assessment. Igeo showed that the contaminated site soil was strongly contaminated with lead (3.21) and lightly contaminated with cadmium (0.05). The API assessment indicated that the soil was very highly contaminated by lead and cadmium (19.37). TSCI and PLI assessment showed that the contamination degree of the contaminated soil with lead and cadmium (38.68 and 13.98 respectively) was very high and the contaminant deteriorated the site. The impact of their activities has immensely contributed to lead, cadmium ions and petroleum hydrocarbon contamination in Evbareke spare parts market vehicle dismantling site soil.
      PubDate: 2022-07-29
      DOI: 10.20372/ejssdastu:v9.i2.2022.434
      Issue No: Vol. 9, No. 2 (2022)
       
  • Indigenous Democratic Governance System in the Horn of Africa: Some
           Reflections on the Democratic Essentials and Political Significance of
           Gadaa System

    • Authors: Kena Deme Jebessa
      Pages: 46 - 52
      Abstract: The Gadaa system is the political governance in which suppression and exploitation of the ruled society by the ruling is strictly forbidden and considered depraved. This study was aimed to assess its reflections both politically and with decency. It solely relied on extensive literature review on democratic governance and Gadaa governance system. The study reveals that the Gadaa system serves as the basis of a democratic and egalitarian political system; with the power to administer the affairs of the nation and the power to make laws belong to the people. All people have the right to air their views in any public gathering without fear that the Oromo Gadaa system has strong democratic elements that concern with all spheres of the nation. Finally, this paper argues that revitalization, institutionalization and rehabilitation of this indigenous democratic governance system can contribute well in development as well as the peace of the Oromo nation and that of the Horn of Africa.
      PubDate: 2022-07-29
      DOI: 10.20372/ejssdastu:v9.i2.2022.455
      Issue No: Vol. 9, No. 2 (2022)
       
  • The Evaluation of Different Blended Fertilizers Types and Rates for
           Improving the Productivity of Wheat (Triticum aestivum L.) in Debub Ari
           District, Southwestern Ethiopia

    • Authors: Abebe Hegano, Atinafu Tunebo, Shimelis Tesema
      Pages: 53 - 61
      Abstract: Production and productivity of wheat is decreased mainly by soil fertility depletion and inappropriate rate of poor nutrients availability. Crop specific fertilizer recommendation is necessary for sustainable crop production. Accordingly, a field experiment was conducted during the main rainy season of 2018 and 2019 to evaluate blended fertilizer types and rates effect on improving production of wheat in Debub Ari district, Southern Ethiopia. The experiment was laid out in Randomized Complete Block Design with three replications. The experiment consisted of 9 treatments viz. control, (142 NPS + 42 urea) kgha -1 , (189NPS + 72Urea) kgha -1 , (142 NPS +102Urea) kgha -1 , (237NPS + 102Urea) kgha -1 , (150NPSB+ 41Urea) kgha -1 , (200 NPSB + 72Urea) kgha -1 , (250NPSB + 102Urea) kgha -1 and (150 NPSB + 161Urea) kgha -1 treatments. Full dose of blended fertilizers were applied at planting time and urea was top dressed after 35 days of planting. Application of blended fertilizer significantly (p < 0.05) increased the plant height, number of tillers per plant, spike length, number of seeds per spike, grain yield, aboveground biomass, and thousand seed weight at harvest as compared to the control. The maximum and significant grain yield (3796.7kg ha -1 ) and minimum (1466.5kg ha -1 ) were obtained from the application of 237 kg ha -1 NPS + 102kgha -1 Urea and control treatment, respectively. The application of 237 kg ha -1 NPS + 102kgha -1 Urea had maximum and acceptable Marginal rate of return (MRR %) and net benefit. Therefore, this type and rate of blended fertilizer can be recommended since it produced a high marginal rate of return, high net benefit, and relatively low total cost of production, for wheat production in the study area and other similar agro-ecologies.
      PubDate: 2022-07-29
      DOI: 10.20372/ejssdastu:v9.i2.2022.414
      Issue No: Vol. 9, No. 2 (2022)
       
  • Synthesis and Characterization of Silica from Awash Melkaasa Chemical
           Factory Waste

    • Authors: Robel Mehari Tesfaye, Fana Teklemariam, Hailemariam Aweke, Hailemariam Gebregwergis
      Pages: 62 - 67
      Abstract: Silica is a common name for the chemical compound silicon dioxide. It can be found naturally in abundant amount as sand and is a raw material for many useful chemicals like silicone and silicates. It can be also found as a by-product from several chemical factories. Awash melkassa is one of the factories that releases this silica as a waste product. In this work, this waste, that has a silica content of more than 65%, was used as a raw material for synthesis of purified silica. Here the silica was prepared by two distinct routes: basic and acidic routes. In basic route, the chemical factory waste have been leached with caustic soda to prepare sodium silicate followed by reducing the silicate with an organic acid to prepare purified silica then finally size reduction by ball milling. In the second method, inorganic acids such as sulfuric acid and hydrochloric acid have been used to remove the impurities from the chemical factory waste and ball milling the purified silica to obtain the micro particles. Characterization of the final products was done by SEM and XRD. Finally the best process for silica synthesis have been decided based on which process yields the higher silica content product which is the acidic routine.
      PubDate: 2022-07-29
      DOI: 10.20372/ejssdastu:v9.i2.2022.483
      Issue No: Vol. 9, No. 2 (2022)
       
  • Estimation of Relativistic Mass Correction for Electronic and Muonic
           Hydrogen Atoms with Potential from Finite Size Source

    • Authors: Eshetu Diriba Kena, Gashaw Bekele Adera
      Pages: 68 - 77
      Abstract: The simplest atom known to exist in nature is electronic hydrogen atom, which helps us to study fundamental properties and structure of atoms. We can also have muonic hydrogen by replacing electron with muon. In this paper, we revisit Schrodinger equation as an attempt to address the relativistic mass correction to electronic and muonic hydrogen-like atoms with potentials from finite size sources. This study is done with the assumption that the changes in both energy eigenvalues and eigenfunctions are negligible when considering the finite size of the nuclei. The relativistic mass corrections to  and  states using potential from finite size source are obtained and compared with corrections using potential from point-like source. The results show that, for hydrogen-like atoms with light nuclei the relativistic mass corrections due to the finite size source roughly coincides with that of point-like source. However, for atoms with heavy nuclei the two corrections display strong disagreement in which the corrections with finite size nuclei are significantly smaller than that of point-like nuclei.
      PubDate: 2022-07-31
      DOI: 10.20372/ejssdastu:v9.i2.2022.474
      Issue No: Vol. 9, No. 2 (2022)
       
  • Challenges and Solutions in Biogas Technology Adoption in Ethiopia: A Mini
           Review

    • Authors: Natei Ermias Benti, Ashenafi Abebe Asfaw
      Pages: 78 - 95
      Abstract: Biogas is a gas that is produced when organic matter decomposes. Biogas produced by anaerobic digestion may be a viable energy source for rural Ethiopia. It is suitable for cooking as well as generating electricity. There are over 18,000 biogas digesters dispersed throughout Ethiopia, and despite the benefits of addressing energy-related issues like environmental and energy scarcity, the country's use of biogas is not rising dramatically. This article provides an overview of biogas technology in Ethiopia and discusses the obstacles and opportunities associated with its expansion. High initial investment costs for digesters, a lack of biogas substrates, a lack of biogas research, a failure of the biogas pilot phase, a lack of public awareness campaigns, insufficient construction and maintenance expertise, low biogas technology efficiency, minimal biogas application, and a lack of appropriate bio-slurry management were identified as barriers to biogas technology expansion in the country. It was stressed that biogas plants installed throughout the country, particularly in rural areas, should be sized appropriately for the substrate available. Furthermore, the calorific value of biogas should be increased in order for it to be used to power generator sets and internal combustion engines.
      PubDate: 2022-07-31
      DOI: 10.20372/ejssdastu:v9.i2.2022.484
      Issue No: Vol. 9, No. 2 (2022)
       
  • Development in the Synthesis and Biological Activities of
           THβ-carboline and Its Analogs: Review

    • Authors: Ayana Melaku Yadessa, Nigatu Bejigo
      Pages: 96 - 123
      Abstract: 1,2,3,4-Tetrahydro-β-carbolines (THβCs) are a large group of natural and synthetic indole alkaloids that possess a common tricyclic pyrido[3,4-b] indole scaffold that are widely distributed in nature. The scaffold and its derivatives are of great interest due to their diverse biological activities and applied in medicine as therapeutic agents. These days, the importance of these compounds in inspiring drug discovery programs is proven and, therefore, their continued synthesis is of great interest. Therefore, this review summarizes the development in their synthetic methods that has been done over the past decades. The review also presents a comprehensive and recent finding on the biological activities of THβCs over the past seven years. The review on β-carbolines might serve as a good reference to promote its inclusion in the planning and synthesis of future drugs Key words: β-carbolines, indole scaffold
      PubDate: 2022-08-04
      DOI: 10.20372/ejssdastu:v9.i2.2022.460
      Issue No: Vol. 9, No. 2 (2022)
       
 
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