A Comparative Study on Removal of Toxic Mercury and Chromium Using Synthesized Inorganic Complex (WOx-EDA) and Compound (AA) Through a Batch Adsorption Process

Toxic metals ions are well known undesirable pollutant in drinking water. Since they are barely biodegradable and can be accumulated in human body through the food chain to induce a severe threat to human health; it is of great importance to develop low cost, safe and highly effective adsorbents for the adsorptive removal of those toxic metals. Synthesis and Characterization of Inorganic–organic hybrid Tungsten oxide-ethylenediamine (WOx–EDA) nanowires have been carried out by a simple, low-cost and high-yield solvo-thermal method. Activated Alumina was also synthesized using direct method. Both Tungsten Oxide ethylenediamine and Activated Alumina (AA) were characterized using, Fourier Transform Infrared (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The synthesized inorganic adsorbents adsorption capacities for removing mercury and chromium were investigated using batch adsorption process. The equilibrium data were applied to various sorption kinectic models. The adsorbents adsorptive capabilities were compared. The adsorbents displayed exceptional adsorptive properties; however, WOx-EDA proved to be better adsorbent than activated alumina in terms of removal efficiency. This could be linked to hybrid structure integrated in the functionality of ethylenediamine with the stability of the WOx frameworks. The nanowire morphology and abundant functional amino groups possibly endowed the complex with versatile abilities and highly adsorptive properties. Keywords: Adsorption, Toxic, alumina, Tungsten Oxide Ethylenediamine, Kinetic. DOI: 10.7176/CMR/11-5-03 Publication date:May 31st 201

THE PERCEPTION, AWARENESS AND USE OF GUIDANCE AND COUNSELLING SERVICES BY UNDERGRADUATES OF THE FEDERAL UNIVERSITY OF AGRICULTURE ABEOKUTA, NIGERIA

This research investigated perception, awareness and use of Guidance and Counselling Services (G&CS) by undergraduates of the Federal University of Agriculture, Abeokuta (FUNAAB). Simple random sampling technique was used to sample 283 respondents across the ten (10) Colleges in the Institution. Data were collected with the aid of questionnaire and analysed using descriptive statistics such as frequency, percentages, and mean. The questionnaire was subjected to a pilot study that revealed psychometric properties of Cronbach's Apha 0.86. Results revealed that 91.1% of the respondents were aware of G&CS and 74.6% of the respondents currently using the services indicated that it was very helpful. The rating of the counselling needs of the respondents revealed that academic issues with a mean of 3.62 is the most important factor, followed by examination pressure management which had a mean of 3.51. The rating of the perception of students on the quality and effectiveness of G&CS indicated that organized orientation services for fresh students ranked first (mean = 2.55), while effective counselling on personal, social, academic and vocational challenges ranked second (mean = 2.49). The fresher's orientation service received the highest perception (mean = 2.55) among respondents on the quality and effectiveness of G&CS in the institution. The use of G&CS is presently assisting students to attain competencies needed to overcome academic, career and personal concerns. The study concluded that the G&CS needs of the students across the Colleges differ due to the dissimilarities in their disciplines across the University.   &nbsp

Modeling Socioeconomic Factors Affecting Age at Marriage among females in Kogi State, Nigeria

This paper is aimed at determining the effect of socioeconomic factors such as cultural background, level of education and religion in relation to age at marriage among women in Kogi State Nigeria. The survey area is made up of diverse ethnic groups with three major languages. The study reveals that education is an important factor which increases the age at marriage in the State. The study equally proved that religion and cultural background does not affect age at marriage among women in Kogi State, Nigeria. A Saturated one-way and two-way model was fitted to reveal the behavioral pattern of the distribution. Key words: Socioeconomic, Modeling, Marriage, Saturated, Analysis

Experimental Investigation and FE Simulation of the Effect of Variable Control on Temperature Distribution in Orthogonal Metal Cutting Process

The study aimed at building a 3-Dimensional finite element simulation to monitor orthogonal machining process under a dry machining environment. The study was conducted in two stages of experimentation and finite element modelling and simulation (FEMS). The purpose of the experimentation was to obtain data which will be used to validate the FEMS result. The FEMS was carried out with a commercially available solver. The workpiece material employed for the study was mild steel in the form of round bar of solid shaft having 45 mm diameter and length of 500 mm. Mild steel was selected due to its wide range of applications in the fields of manufacturing tools and mould industry. The tool material used was tungsten carbide of DIN4980R 20 mm x 20 mm, with cutting angle of 80-degree tool steel, which was modelled in the FEMS as a rigid body. Various cutting conditions such as speed, feed rate and depth of cut were considered to obtain the tool chip temperature. Different values of temperature were recorded at interval of 10 seconds and ranged from 10 to 100 seconds. The FEMS was carried out by making one of the conditions vary while the others were constant. The temperature values measured with a digital thermocouple were used to validate the FEMS data obtained. The result show that the cutting temperature predicted by the FEMS is within 20% of the real experimental value and followed the same trend. It was discovered that the values of temperature obtained from simulation were also much higher than that of experimentation. Therefore, the experimental value might not be accurate, due to some experimental errors and environmental effects like partial contact between the measuring device and the cutting tools, fluctuation in the magnitude of air flow around the surrounding which may affect the cutting temperature, room temperature and pressure effect. Generally, with an increase in the cutting speed, feed rate and depth of cut, the tool temperature also increased and the cutting speed was found to be the most effective parameter when consideration is given to temperature effects, especially in high range of cutting conditions

A Comparison of the Semi Analytical and Numerical Method in Solving the Problem of Magnetohydrodynamics Flow of a Third Grade Fluid between Two Parallel Plates

The main purpose of this study is to compare a semi-analytical method and numerical method namely the homotopy perturbation method (HPM) and finite difference method (FDM) respectively. These methods were employed for solving the nonlinear problem of the magnetohydrodynamic (MHD) couette flow of third-grade fluid between the two parallel plates. The comparison was made between a solution of HPM and FDM against a solution obtained from regular perturbation and the results are tabulated. From a computational viewpoint, it is revealed that the HPM is more reliable and efficient than FDM. Also, the results show that the FDM requires slightly more computational effort than the HPM, although the HPM yields more accurate results than the FDM. &nbsp

Dissipative Non-Slip MHD Nanofluid Flow with Variable Viscousity and Thermal Conductivity in the Presence of Arrhenius Chemical Reaction

This research investigates the intricate dynamics of dissipative non-slip magnetohydrodynamic (MHD) nanofluid flow, characterized by variable viscosity and thermal conductivity, under the influence of an Arrhenius chemical reaction. The inclusion of the Arrhenius chemical reaction adds complexity through heat generation or absorption, impacting temperature and concentration gradients. The study is motivated by the extensive applications of nanofluids in engineering and industrial processes, where precise control of heat and mass transfer is critical. We develop a comprehensive mathematical model that incorporates the variable properties of the nanofluid, the effects of the Lorentz force due to the applied magnetic field, and the temperature-dependent reaction rates dictated by the Arrhenius equation. The formulated governing equations were non-dimensionalised to identify the flow governing parameters. Finite Element Method (FEM), grid generation, solution algorithms, and post-processing to analyse velocity, temperature, and concentration distributions were used to obtain the numerical methods to solve fluid flow problems based on the Navier-Stokes equations, involving concepts of discretization. pdsolve subpackage in Maple 2023 was used to numerically solve PDEs with specific initial and boundary conditions, incorporating the plot and display commands for graphical analysis, and the results are presented and discussed. The findings reveal that the interplay between parameters like Hartmann number, Darcy parameter, and heat generation or absorption profoundly influences flow behaviour and thermal characteristics. The reactivity parameter is crucial, dictating the rate of chemical reactions and affecting system dynamics. This research enhances understanding of the interdependencies among fluid properties, chemical reactions, and external parameters in nanofluid flows.&nbsp

Navigating housing affordability in Rwanda: Challenges and facilitation strategies

Housing and its affordability have, of recent, been of great concern to various stakeholders, especially in the developing world.  Consequently, contributing aspects such as construction/tenancy costs, sustainability, environmental impact, and availability of credit facilities with a host of other factors, have dominated contemporary research. Various studies suggest that addressing affordable housing requires understanding the contextual factors that impact affordability of housing. Such studies have not been known to succinctly treat  the context of Rwanda. This paper aimed at exploring the perspectives of housing affordability in Rwanda with a view of eliciting the status, challenges, and prospects. The objectives included description of the current status of housing, identifying the challenges of  providing affordable housing, and proposals of strategies to enhance its provision. Data, such as for workers’ salary, costs of house construction, inflationary trends and the number of housing units per income group, were sought for and obtained either from the  archives of various stakeholder organizations or by interviewing key officers concerned with housing. Descriptive statistics and thematic  analyses were employed in analyzing the data in order to fulfil the objectives of the study. It was found that home ownership and tenure statistics varied, yet housing demand was on the rise. Foremost challenges, among others, were recorded to be scarcity and costly plots of land, compounded with costly building materials. In addition, the purchasing power of the local currency depreciated fast over time, thereby making good quality housing unaffordable for the majority of Rwandans. Localizing policy to enhance public awareness, resolving the issue of high cost of construction materials, and coming up with innovative interventions on land costs, were among the key strategies to facilitate housing affordability

An Experimental Approach towards PV-Based Solar System Sizing for an Engineering Laboratory

This study aims at providing an experimental sizing procedure for a rooftop PV-based solar power system for an engineering laboratory. This was achieved by monitoring the peak power and energy delivered by an installed 20W solar panel into an 18 Ah battery. Knowledge of the average daily peak power and energy was used to determine the percentage rated capacity available for use and the sun hour. A load consumption comparison was also carried out with and without the connection of a load to inverter. In addition to this, the monitoring of the no-load consumption of the inverter was carried out. This was carried-out to ascertain the contribution of the inverter to the system. With the knowledge of the average daily energy deliverable, sun hour and the no-load power of the inverter, a sample sizing for basic electronic laboratory loads was done. The findings of the study reveals that the average available power is 89.35% of the solar panel rated capacity while the average sun hour is 4.38 h. It has also been shown that an approximate difference of 20 W exists between the power consumption of the load with and without its connection to the inverter. This value (i.e., 20W) has been recorded as the approximate no-load power for the inverter. The sample sizing done has shown that, the solar panel energy requirement of the system with inverter may be considerably higher than that without inverter

Heme oxygenase-1 attenuates cadmium-induced mitochondrial-caspase 3- dependent apoptosis in human hepatoma cell line

Background: Cadmium (Cd) is a well known environmental and industrial toxicant causing damaging effects in numerous organs. In this study, we examined the role of heme oxygenase-1 (HO-1) in modulating the Cd-induced apoptosis in human hepatoma (HepG2) cells after 24 h exposure. Methods: HepG2 cells were exposed to 5 and 10 μM Cd as CdCl2 for 24 h while other sets of cells were pre-treated with either 10 μM Cobalt protoporphyrin (CoPPIX) or 10 μM Tin protoporphyrin (SnPPIX) for 24 h, or 50 μM Z-DEVD-FMK for 1 h before exposure to 5 and 10 μM CdCl2 for 24 h. Expressions of caspase 3, cytosolic cytochrome c, mitochondrial Bax and anti-apoptotic BCL-xl proteins were assessed by western blot. Intracellular reactive oxygen species (ROS) production was determined using the dihydrofluorescein diacetate (H2DFA) method. Cell viability was assessed by MTT assay, while a flow cytometry method was used to assess the level of apoptosis in the cell populations. Results: Our results show that there were a significant increase in the expression of cytosolic cytochrome c, mitochondrial Bax protein, and caspase 3 at 5 and 10 μM compared to the control, but these increases were attenuated by the presence of CoPPIX. The presence of SnPPIX significantly enhanced Cd-induced caspase 3 activities. CoPPIX significantly decreased the level of ROS production by 24.6 and 22.2 % in 5 and 10 μM CdCl2, respectively, but SnPPIX caused a significant increase in ROS production in the presence of CdCl2. HepG2 cell viability was also significantly impaired by 13.89 and 32.53 % in the presence of 5 and 10 μM CdCl2, respectively, but the presence of CoPPIX and Z-DEVD-FMK significantly enhanced cell survival, while SnPPIX enhanced Cd-impaired cell viability. The presence of CoPPIX and Z-DEVD-FMK also significantly decreased the population of apoptotic and necrotic cells compared with Cd. Conclusion: In summary, the present study showed that HO-1 attenuates the Cd-induced caspase 3 dependent pathway of apoptosis in HepG2 cells, probably by modulating Cd-induced oxidative stress