Mrs. MODEBE LUCY UJU
Publication Title Studies on Phase Overlapping Analysis of Jatropha Oil Biodiesel Ternary Components at Different Temperatures
Publication Type journal
Publisher NIPES Journal of Science and Technology Research
Paper Link https://doi.org/10.5281/zenodo.7728321
Publication Authors Kenneth Kennedy Adama and Lucy Uju Modebe
Year Published 2023-03-13
Abstract In this study, components phase partitioning of jatropha oil biodiesel
ternary system is investigated. Modified turbidimetric technique was
used to investigate the constituent compositions at nine different
temperatures (20 – 60) °C. Analysis of the homogeneous mixture was
conducted using gas chromatographic approach. The influence of
temperature on the immiscibility region and the separating capacity of
the solvent (methanol) was determined from distribution coefficient (K)
and solvent selectivity (S) analysis. The results revealed how the
individual components of the ternary system distributed in the
homogeneous solution at the different temperatures thereby displaying
large two-phase envelope. However, high level of immiscibility
between the extract and raffinate phases at all investigated
temperatures was also observed. The results further revealed
overlapping tie lines which was linked to the presence of excess
methanol in the feed composition and further emphasized the fact that
the tie lines overlap because other components were simultaneously
distributed between the extract and raffinate phases. This study
provides important property statistics for bio-based biodiesel
components separation which are of interest in process design,
optimization and simulation
Publication Title Experimental Analysis of Anisotropic Surface Texturing Process ofCrystalline Silicon Wafers
Publication Type journal
Publisher Journal of Materials Engineering, Structures and Computation
Paper Link https://doi.org/10.5281/zenodo.7759299
Publication Authors Adama K. K., Emegha J.O., Ukhurebor E.K. and Modebe L.U.
Year Published 2023-03-23
Abstract The development of silicon devices, circuits, and systems in most cases relies on the wet-chemical etching of silicon wafers (SWs). To achieve deep etching and micromachining, shaping, as well as cleaning, the dissolution of silicon using liquid chemical solutions is imperative. This study reports an experimental investigation of surface texturing of silicon wafers using a mixture of aqueous potassium hydroxide (KOH) solution and isopropyl alcohol (IPA) as a complexing agent to enhance light absorption and reduce the optical reflectance in the visible spectrum. Crochralski (CZ) silicon wafers of 100 mm diameter, 2” <100>-oriented, n-type, resistivity (?cm) of 7-21, with polished and lapped surfaces were utilized in the experiment. The process variables investigated included temperature (60 –90) °C, duration of etching time (30 –60) mins and concentration of KOH and IPA of (1 -4) mg/l for KOH and (2 –8) mg/l for IPA. The properties of the etched and unetched silicon wafers in terms of morphology, structure, photoluminescence, and electroluminescence were investigated to determine the effects of the process parameters on the efficiency and structural properties of the textured wafers. The SEM measurements revealed the presence of localized roughening pyramidal images. This showed that the use of KOH and IPA solutions on the silicon wafers revealed pyramidal structures that can be used to control the optical reflectance of the silicon wafers due to light scattering by the localized roughening. The applied etching procedure also produced low-reflecting materials whose reflectivity increases with wavelength. This study shows that textured material has great potential in optoelectronic device manufacturing processes.
Publication Title Synthesis of Zero Valent Nickel Nano Biochar Composites from Guava Leaf Extract for the Adsorption of Heavy Metals from Wastewater
Publication Type journal
Publisher Journal of Water Resources and Pollution Studies ISSN: 2581-5326Volume-8, Issue-2 (May-August, 2023)
Publication Authors Michael Chika Egwunyenga, Wisdom Chukwuemeke Ulakpa, Lucy U. Modebe and Cyril O. Anakpoha
Year Published 2023-03-27
Abstract Aforesaid materials has weaknesses as adsorbents, the rising demand for adsorption as a wastewater treatment approach demands the search for a suitable composite that combines the benefits of nanoparticles and porous support material. In this study, zero valent nickel nano particles were produced and immobilized/deposited on the zinc chloride-activated surface of Biochar for wastewater remediation. Psidium guajava (Guava) leaves were gathered and the leaf extract was made; subsequently, nickel nanoparticles were biosynthesized utilizing the obtained leaf extract as the reducing agent. Furthermore, Zincchloride-activated biochar was employed as a support medium for the inclusion of the Nickel nano biochar composite. The morphological structures, crystalline natures, and functional groups of the nickel nanoparticles (NiNPs) and nickel nano biochar composite were determined using High-Resolution Scanning Electron Microscopy (HRSEM), X-ray powder diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR), respectively. This study's findings suggest that the synthesized nanocomposite can be employed in wastewater treatment.