Abstract: Lead and Copper are inorganic pollutants that are non-biodegradable. When released into the environment, they have adverse effect on human beings and animals when ingested. Allium cepa (Onion) is a vegetable product largely consumed for its potential therapeutic importance. This study investigates the efficacy of Allium cepa in removal of Cu2+ and Pb2+ from human blood plasma in-vitro. The adsorption rate was studied at optimum values of pH 6 for Cu2+, and pH 4 for Pb2+, metal ion concentration (50mgL-1), and Allium cepa dose 0.60g for Cu2+ and 0.40g for Pb2+ at physiological temperature (38°C). SEM analysis revealed physical disintegration in the surface morphology of Allium cepa biomass after adsorption. Equilibrium sorption occurred at80 mins with 99.316% removal for Cu2+ and 90minswith 99.8914% removal for Pb2+. The adsorption data obtained for Cu2+ best fits Temkin isotherm with correlation value (R2)=0.901 with low binding energy (AT)=1.340 Lg-1 while the adsorption data for Pb2+ best fits Freundlich isotherm with correlation values (R2)=0.965 at Freundlich coefficient (kf)=3.169.27 Lmg-1. The result also revealedthat physiosorption and chemosorption occurred between the metal ions and binding site on the Allium cepa biomass as Intraparticle diffusion proved not to be the only rate controlling step.Abstract: Lead and Copper are inorganic pollutants that are non-biodegradable. When released into the environment, they have adverse effect on human beings and animals when ingested. Allium cepa (Onion) is a vegetable product largely consumed for its potential therapeutic importance. This study investigates the efficacy of Allium cepa in removal of Cu2+ and ...Show More
Abstract: Cost optimization is a process that should be carried out throughout the construction period to ensure that the cost of the project is within an allotted budget. Time and cost are the two most significant factors in any construction project. Cost increases with the time of construction. The objective of this study was to find out the factors that contribute to the optimization of construction costs in building construction projects in Nepal. The study was conducted during the period from April 2019 to September 2020. Field observation, in-depth interviews, focus group discussions and questionnaire surveys were the major tools for the investigation of this study. The findings were analyzed in nine categories: project related factors, design related factors, owner related factors, consultant related factors, contractor related factors, material related factors, labor related factors, equipment related factors, and external factors. The study found some key factors related to time and cost overrun, optimizing cost of construction and the strategies to optimize project costs. The most important strategy to optimize the construction cost are effective cost planning and control, development of proper monitoring and tracking system, sound working environment, recording daily work progress, using time cost trade off, follow plan-do-check-act quality policy, hire skilled labor and effective supervision. The study suggests that constructability and value engineering principles should be adopted in construction projects.Abstract: Cost optimization is a process that should be carried out throughout the construction period to ensure that the cost of the project is within an allotted budget. Time and cost are the two most significant factors in any construction project. Cost increases with the time of construction. The objective of this study was to find out the factors that c...Show More