IOSR-JAP   Volume-13 ~ Issue-4 ~ Jul. – Aug. 2021

ABSTRACT: Dye sensitized solar cells were successfully fabricated using deionized water and ethanol to extract natural dye from Bush tea (Hyptis Suavelens). Nanocrystaline titanium (iv) oxide (TiO2) (solaonix SA) was deposited on the working electrode by Dr. Blade method and Platinum catalyst was deposited on the counter electrodes using screen printing method. The optical properties of the solar cells were investigated using Ava Spec-2048 UV/Visible Spectrophotometer. Electrical properties of solar cells were characterized using Oriel Class A Solar Simulator. The I-V characterization of the cells was measured in dark and illumination intensity and the illumination intensity used was....

Keywords: dye sensitized, solar cells, Nanocrystaline Titanium

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ABSTRACT: In nature every semiconductor material needs to be doped. Sometimes to nearly degenerate level, eg. In applications such as thermoelectric, transparent, electronics or power electronics. However, many materials with finite band gaps are not dopable at all, while many others exhibit strong preferences towards allowing either p-type or n-type doping, but not both. In this work we develop a model of strained InGaAs/GaAsSb double barrier quantum well heterostructure on InP substrate using the model solid theory. The matlab program model was used to obtain the conduction and valence band offsets and their ratios,. These were obtained theoretically by employing experimental binary band parameters obtained from literatures.

Keywords: Band Offsets; Intrinsic; Electron concentration; Strained Conduction Band.

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ABSTRACT: Al Doped CoO thin film [ACO] were successfully deposited on amorphous glass substrates using Successive Ionic Layer Adsorption and Reaction deposition method [SILAR]. The deposited film were annealed at temperature of 300oC and the annealed time varied for 1hr, 1hr.15mins, 1hr.30mins, 1hr.45mins and 2hrs. Thin films of ACO were deposited on glass by successive immersion of the substrate into a complex (NH4) AlCoCl2 bath kept at room temperature. 3ml of 3M solution of ammonia (NH4) used as a complexing agent was measures and added into a beaker with 40.0g of 0.6M of CoCl to form a complex cobalt ion, 10% of AlCl2 was also measured and added as a dopant....

Keywords: [Aluminum, Cobalt oxide, thin films, Annealing time,]

[1]. Ananda, K. and Rajendran, V. Morphological and size effect of NiO nanoparticle via solvothermal process and their optical properties. Material Science and Semi-Conductor Process, (2011), 14(1) 43-47.
[2]. Avila . G., Barrera . C., Huerta L. ., a d Mu l, S. "Structural and Electrical Characterization of Cobalt Oxide Semiconductors. Solar Energy Material and Solar Cells, (2004), 82; 269-275. "
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ABSTRACT: A limited-extent test of the validity of using a statistical tool in conjunction with acquired ground electrical resistivity data to build a protocol that could ease the efforts and cost that is put into acquiring labourious vertical electrical sounding (VES) data-field in a geologically-similar locality has been completed at the 4 km2 southern Phase II Development of the Gidan Kwano Campus, Minna, Nigeria. The arbitrarily-fixed very high correlation threshold chosen for that study ensured that the statistical tool under consideration was given a negative recommendation even though the fundamental mathematics of this method was sound and the prevailing geology was encouraging. The aim of this study is to expand the scope of that previous study so as to further examine the results of the simple regression analysis (SRA) method as applied to the corpus of the 4 km2 VES data-field for a more....

Keywords: VES; resistivity; groundwater; statistical-analysis; SRA

[1]. Akca, I. (2016). ELRIS2D: A MATLAB package for the 2D inversion of DC resistivity/IP data. Acta Geophysica, 64 (2), 443-462.
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[5]. Jimoh, M.O. (1998). Report on the Six Boreholes Drilled at the Main Campus of the Federal University of Technology, Minna, for the Petroleum (Special) Trust Fund. Cemaco Ventures Ltd., Minna..

ABSTRACT: In this work, the variations of photon attenuation coefficients at varying photon energies by different naturally occurring soil textures to ascertain their suitability for radiation shielding purposes were investigated. The photon attenuation coefficient of different textural classes of soils is of extreme importance in shedding light on the properties of soils in many applications. Eight (8) different soil textural classes' samples from four (4) different locations in Ibadan, southwest Nigeria were collected and prepared for atomic absorption spectroscopic, AAS elemental analysis. Using a Buck scientific 210 VGB Atomic Absorption Spectrophotometer located at the SMO laboratory in Ibadan, Nigeria in the flame configuration mode, this analysis reveals the presence of 12 elements....

Keywords: Photon attenuation coefficient, Radiation shielding, Soil textural class, Atomic absorption spectrometry, Elemental concentration

[1]. Adejumo, O.O (2009). Soil Bulk Density and Water Content Measurements of Southwestern Nigerian Soils by Dual Energy Gamma-Ray Transmission Method. Ph.D. Engineering Physics Thesis, Obafemi Awolowo University, Ile-Ife, Nigeria.
[2]. Adejumo, O.O & Balogun, F.A (2012). Using the Dual Energy Gamma-Ray Transmission Technique to Measure Soil Bulk Density and Water Content of Central Southwestern Nigerian Soils. Journal of Environmental Protection, 3, 1409-1427.
[3]. Adejumo, O.O, Balogun, F.A & Ogundare, F.O (2015). The Variations of Gamma-Ray Attenuation Coefficients with Depth for Southwestern Nigerian Soil Types. Journal of Earth Sciences and Geotechnical Engineering, 5(4), 45 – 56.
[4]. Al-Masri, M.S, Hasan, M, Al-Hamwi, A, Amin, Y & Doubal, A.W (2013). Mass attenuation coefficients of soil and sediment samples using gamma energies from 46.5 to 1332 keV. Journal of Environmental Radioactivity 116, 28 - 33.
[5]. Berger, M.J., Hubbell, J.H., Seltzer, S.M., Chang, J., Coursey, J.S., Sukumar, R., Zucker, D.S., & Olsen, K. (2010), XCOM: Photon Cross Section Database (version 1.5). [Online] Available: http://physics.nist.gov/xcom [18 June 2020]. National Institute of Standards and Technology, Gaithersburg, MD..

ABSTRACT: The trend of variability of temperature in Awka, Anambra State was studied using ten years monthly minimum and maximum temperature(0C) readings from 2011 to 2020 obtained from NIMET Amawbia, Awka Anambra State. The result of the analysis revealed that the highest and lowest mean monthly temperatures of 29.920C and 26.380C were obtained in March and August respectively. The result of the variability of annual mean temperature for the ten years period showed that Awka is getting hotter with highest and lowest annual mean temperature of 28.130C and 27.400C obtained in the year 2020 and 2018, respectively. This showed that the year 2020 with an increase in temperature of about 0.730C from 2018 to 2020 is the hottest year among the tenyears period studied.

Keyword: Variability, Temperature, Awka, Annual, Mean

[1]. America's Climate Choices, (2011)National Academy of Sciences Press, United States of America134pagse
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[5]. Ezenwaji EE, Nzoiwu CP, Umeogu CC, (2018) Contribution of Rainfall and other Meteorological factors to Building collapse in Urban Areas of Anambra State. Environmental Review 6:1.

ABSTRACT: The trend of rainfall in Awka from 2011 to 2020 was examined using monthly rainfall data collected from Nigerian Meteorological Agency (NIMET) Synoptic Station at Amawbia, Awka, Anambra State. The study considered monthly rainfall for each year, mean monthly rainfall from 2011-2020 and the annual rainfall from 2011-2020. It was found out that the month with the highest rainfall varies from June, July, August and September with September 2019 having the highest monthly rainfall of 906.00mm and February 2014 having the lowest monthly rainfall of 2.60mm. The result from the mean monthly rainfall has September with mean monthly rainfall of 475.37mm as highest......

Keyword: Rainfall, variability, Awka, Annual.

[1]. Abiodun BJ, Salami AT, Tadross M (2011). Climate Changes Scenarios for Nigeria: Understanding Biophysical Impacts. Climate System Analysis Group, Cape Town, for Building Nigeria's Response to Climate Change (BNR CC) Project. Ibadan, Nigeria: Nigeria Environmental Study/Action Team (NEST).
[2]. Ayoade, J.O. (1993), Introduction to climatology for the Tropics. Spectrum book Ltd. Ibadan, pp. 204 – 220
[3]. Bardossy A (2001). Statistical Investigation of Precipitation Changes form a Hydrological Viewpoint. In Lozan J, GraBI H. and Hupfer P. (Eds) Climate of the 21st Century: Changes and Risks. WissenschaftlicheAuswerungen, Hamburg, Germany.
[4]. Crowley, T.J., 2000: Causes of climate change over the past 1000 years. Science, 289(5477), 270–277.
[5]. Ezenwaji EE, Nzoiwu CP, Umeogu CC, (2018) Contribution of Rainfall and other Meteorological factors to Building collapse in Urban Areas of Anambra State. Environmental Review 6:1

ABSTRACT: The measurement of the vertical profiles of rainfall parameters such as drop size distribution, rain rate, liquid water content, fall velocity and radar reflectivity were carried out by using Micro Rain Radar in 2006 and 2008 at Akure (Lat 5°15'E, long 7°15'N) in South-Western Nigeria. The vertical distributions of these parameters with heights are presented for 0 - 4800 m.The range gates for the measurement are 30 with a height step of 160 m. The variation of the drop size distribution, rain rate and liquid water content with height were evaluated. The highest rain rate and liquid water content were observed within the height range 0-160 m. For the all cases considered, the largest concentration of drop size with a diameter of 0.246 mm occurred in the height range 0- 160 m.....

Keywords: Stratiform rain; Convective rain; Micro Rain Radar; Rain rates, Radar reflectivity, Attenuation and Tropical region

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ABSTRACT: Nanotechnology portrays the depiction, assembling and control of plans, contraptions or materials that have something like one perspectives that are more humble than 100 nanometers. This region has set up areas of strength for a for itself as a principal enabling technology for endless purposes, subsequently changing into a fundamental worry for science and technology method improvement, being at present used in different things among the cutting edge locale, unequivocally, electronic, clinical benefits, delivered, brilliance care things, composites and energy. Disregarding the improvement around here, there are a few hindrances to a more unmistakable impact of nanotechnology in industry. The mishap of information concerning this genuine district, the possibility undermining impacts of nanotechnology on the environment, human achievement, security and sound judgment, are at this point a test......

Keywords: Nanotechnology, Nanocomposites, Nanomaterials

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