Adama University

About: Adama University is a education organization based out in Nazrēt, Ethiopia. It is known for research contribution in the topics: Population & Adsorption. The organization has 840 authors who have published 1010 publications receiving 5547 citations. The organization is also known as: Adama Science and Technology University & ቴክኖሎጂ ዩኒቨርሲቲ, አዳማ ሳይንስና ቴክኖሎጂ ዩኒቨርሲቲ.

Synthesis and characterizations of (Mg, Co, Ni, Cu, Zn)O high-entropy oxides

Abstract: High-temperature structural ceramic materials require stability in terms of thermal and mechanical properties. High entropy oxides (HEOs) are among the emerging novel family of advanced ceramic materials with peculiar functional properties. However, their thermal stabilities and mechanical properties are not well investigated. In this work, HEO systems were synthesized from binary oxides of MgO, CoO, NiO, CuO, and ZnO using solid-state reaction method at high temperature, after obtaining the individual oxides through co-precipitation methods. The phase purity of as-synthesized and sintered samples was characterized using X-ray powder diffraction, while the microstructural investigation was performed using Scanning electron microscopy. Mechanical property of the sintered samples at different sintering times and temperatures was investigated and the sample sintered at a sintering temperature of 1200 °C for 15 h sintering time showed a maximum Vickers hardness of about 16 GPa. This result is comparable with some of the hard ceramic materials, and therefore the materials could be a potential candidate for structural applications.

TerrorWatch: A Prototype Mobile App to Combat Terror in Terror-Prone Nations

Abstract: Activities of prominent terrorist groups like Boko Haram, Al-Shabaab, Ansaru, and Ansar Dine have left thousands of people dead and properties destroyed for a number of decades in some developing nations. The high level of insecurity occasioned by operations of terror groups has impacted negatively on the socio-economic development of these nations. On the other hand, the use of mobile devices, such as cell phones, has gained prominence in developing nations over the past two decades. Putting side-by-side these two facts, namely, that the menace of terrorism among some developing nations is alarming and that the use of mobile devices is common among citizens of developing countries, this chapter develops a mobile application prototype called TerrorWatch. TerrorWatch is equipped with relevant menus, buttons, and interfaces that will guide a user on what to do when confronted with a terrorist attack or threat. The unified modeling language (UML) was deployed to design the architecture of the application, while the object-oriented paradigm served in the implementation.

Role of Nanofibers in Encapsulation of the Whole Cell

Abstract: In the field of biomaterial research, the electrospinning device is now used to manufacture nanofibers that can be used to encapsulate whole microorganisms such as bacterial cells, funguses, viruses, and even spores. The nanofiber encapsulated cells will have greater significance in the coming future because of their wide variety of applications in various fields. Nanofibers act as microorganism reservoir systems that enhance their properties such as viability, controlled release of products, biomedical applications, and bioremediation. The effect of electrostatic forces on a droplet of liquid polymer or polymer solution is based on electrospinning. Electrospun nanofibers act as ideal native extracellular matrices for microorganisms and have also had a tremendous advantage in drug delivery systems where modern research is still underway. During electrospinning, nearly all microorganisms may be inserted into a polymer matrix that forms a composite nanofiber. The evolution in electrospinning technique over the past few decades has become promising. New ideas have been generated to enhance the techniques and improve the overall applications and properties of nanofibers. This technique has been transformed by the advent of the electrospinning machine. The electrospun nanofibers can be chemically characterized by a wide variety of procedures such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). Electrospinning has various applications, for example, in wastewater treatment, tissue engineering, food industry, drug delivery, agriculture, and cosmetics. Nanofiber encapsulation of microorganisms increased the shelf life of the microorganisms; the cells remain viable for months. It also helps in the control release of bacterial products. The present review demonstrates the role of nanofiber in the encapsulation of the whole cell.

Hydraulic Performance Assessment of Mychew Small Scale Irrigation Scheme, North Ethiopia

Abstract: Performances assessment of irrigation schemes network is very essential in taking different water management strategies. However, the performance of Mychew irrigation scheme was not assessed and hence, this research was undertaken to assess the hydraulic performance of Mychew small scale irrigation scheme. Moreover, identification of the cause and effect for mal-functionality of irrigation structures was also another objective of this study. Hence, comprehensive field observations, measurements and focus group discussions were held to investigate hydraulic performance, cause and effect of failed hydraulic structures. Simple descriptive statistics was employed for analysis of the data collected from focus group discussions and observations. Eight performance indicators were used to assess the performance of this irrigation scheme. Several factors such as sedimentation, design problem, damage of sluice gates, abstraction of irrigation water by unwanted plants has been identified for mal-functionality of different structures. There were problems in irrigation adequacy (0.75) and equity (0.28) of irrigation water was categorized as poor, while good and fair for dependability (0.08) and irrigation efficiency (0.79), respectively. The average water surface elevation ratio, delivery performance ratio, and delivery duration ratio of the main canal during the monitoring period was less than one, greater than 5% and 150%, respectively. The highest sediment accumulation was observed at head and middle reaches of the irrigation scheme than the tail reaches. Generally, there were a number of irrigation structures which was mal-functioned in this irrigation scheme. Now it needs sustainable solution to improve the performance of the irrigation scheme. Therefore, it was recommended that water should be fairly distributed spatially and temporally. Additionally, capacity building and awareness creation to concerned bodies holds the key to bring a difference in irrigation water management in this irrigation scheme.

Green Synthesis of CuO Nanostructures using Syzygium guineense (Willd.) DC Plant Leaf Extract and Their Applications

Abstract: The medicinal plant, Syzygium guineense (Willd.) DC (Waterberry) mediated green copper oxide nanostructures (SyG-CuO NSs) were successfully synthesized for the first time in Ethiopia. The antibacterial activity of CuO NSs capped by biomolecules of the plant leaf extract has been investigated. The UV-visible, UV-DRS, FT-IR, XRD, TGA-DTA, SEM, EDXA, TEM, HRTEM and SAED techniques were employed to characterize the NSs. The presence of two absorbance maxima, λmax1 and λmax2 at 423 nm and 451 nm, respectively confirms a mixture of copper oxide (Eg=1.93 eV). FTIR spectra confirmed the presence of biomolecules with SyG-CuO NSs. The XRD patterns of NSs confirmed the presence of CuO with high crystallinity. The purity of the NSs was confirmed by SEM-EDAX analysis. In addition, TEM-HRTEM-SAED analysis revealed the d-spacing value of 0.2854 nm which corresponds to CuO (111) lattice fringe. SyG-CuO NSs showed good antibacterial effect against both Gram-positive bacteria, S. aureus (12 mm), and Gram-negative bacteria, E. coli (12 mm), P. aeruginosa (10 mm), and E. aerogenes (12 mm). The bioactive compounds capped around the CuO NPs served the effective role in disrupting the cell wall of bacterial strains. The CV and EIS studies confirmed the better electrochemical properties for SyG-CuO with low charge transfer resistance value of 49 Ω. These CuO NSs exhibited multifunctional applications.