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.

Recent progress in electron transport bilayer for efficient and low-cost perovskite solar cells: a review

Abstract: Today, organic–inorganic perovskite hybrid solar cells are especially attracted by the energy industries to design and develop new-generation photovoltaic devices. They are the most promising materials for high PCE and cheap solar cells. They can also solve the current energy demand of society and the global crisis. Over the past few years, the power conversion efficiency (PCE) of perovskite solar cells (PSCs) has increased rapidly from 3.8 to 24.2%. However, the review focuses on the recent development of the electron transport layer due to the most important parameter perovskite solar cells to enhance the performance and stability of the device. These summaries discuss device architectures, single and double electron transport (ETL) layers, ETL optimization, and perovskite active layer interface for efficient perovskite solar cells. Moreover, the doping effects on the charge transport layer/window layers of PSCs were reviewed. In addition, the performance and stability issues for organic–inorganic halide perovskite solar cells are discussed here. Finally, future research on bilayer ETL and the perovskite active layer interface was also offered.

On Some Coupled Fixed Point Theorems with Rational Expressions in Partially Ordered Metric Spaces

Abstract: The aim of this paper is to prove some coupled fixed point theorems of a self mapping satisfying a certain rational type contraction along with strict mixed monotone property in an ordered metric space. Further, a result is presented for the uniqueness of a coupled fixed point under an order relation in a space. These results generalize and extend known existing results in the literature.

Synthesis of Magnetically Recoverable Ru/Fe3O4 Nanocomposite for Efficient Photocatalytic Degradation of Methylene Blue

Abstract: Photocatalytic degradation of pollutants is considered to be an effective green method to remove organic dyes from contaminated water. This research work presents the synthesis of a magnetically recoverable ruthenium-magnetite (Ru/Fe3O4) nanocomposite for the photocatalytic degradation of methylene blue (MB) in an aqueous solution under UV and sunlight radiation. The magnetic Ru/Fe3O4 nanocomposite is synthesized in a single step using the chemical co-precipitation method. The synthesized nanocomposite sample is characterized by various techniques, including, XRD, FT-IR, SEM, TEM, TEM–EDX, XPS and VSM whereas the photocatalytic degradation of MB is analyzed by the UV–Vis spectrophotometer. The formation of ruthenium nanoparticles in magnetic Fe3O4 has been confirmed by TEM, TEM–EDX and XPS studies. The catalytic activity of the synthesized Ru/Fe3O4 nanocomposite is evaluated by photodegradation of the MB dye aqueous solution under UV and sunlight radiation. The influences of various operation parameters on photocatalytic degradation such as pH, dye initial concentration and catalyst dosage are examined. The results revealed a complete photocatalytic degradation of MB in the aqueous solution occurred by exposure to both UV and sunlight radiation. Furthermore, the photocatalytic degradation of MB under UV light is faster than sunlight. The photocatalytic degradation reaction of MB is found to be consistent with the pseudo-first-order kinetics. The strong ferromagnetic nature of Fe3O4 enables the nanocomposite to be separated from the solution for recycling and has a photocatalytic efficiency of greater than 90% for up to five cycles. The synthesized Ru/Fe3O4 photocatalyst efficiently degrades MB dye, so it can be used as a potential catalyst for the removal of MB in aqueous solutions.

Design of Slow Sand Filter Technology for Rural Water Treatment in Girei, Adamawa State, North Eastern Nigeria

Abstract: Treatment of water has a great influence on the use of water for domestic use both in rural and urban areas. Slow sand filtration involves the use of beds of sand for the filtration of water. The reason for designing slow sand filter for rural water treatment is to make treatment of water easy and qualitative. This research involves the use of three tanks, filter beds, filter media and filtrate tanks. Raw water is filtered by the layers of different sand particles, and conveyed by pipe after filtration to the filter media that has diatomite as the sieving agent which filters the water before been conveyed into the filtrate tank. From test carried out, the result shows that slow sand filter with filter technology is moderately efficient for water treatment. The design of slow sand filter technology applied appropriate technology; hence the ease of filtering raw water as well as improvement in taste and odor of water being treated was achieved. However, chemical and biological contaminants were not considered in this research. Original Research Article Ankidawa and Tope; AJEE, 3(3): 1-7, 2017; Article no.AJEE.34395 2

Properties and Applications of a Transmuted Power Gompertz Distribution

Abstract: Department of Physical Sciences, Benson Idahosa University, Benin City, Nigeria. Department of Mathematical Sciences, Taraba State University, Jalingo, Nigeria. Department of Statistics and Operations Research, Modibbo Adama University of Technology (MAUTech), P.M.B. 2076, Yola, Nigeria. Department of General Studies Education, School of General Education, Federal College of Education, Yola, Adamawa State, Nigeria.