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General metabolic activity rises with increasing temperature in farm produce, which commonly leads to post-harvest losses. In recent times, control of temperature has been used successfully to control deterioration and maintain viability of these farm produce. This study focused majorly on post-harvest losses which are a recurring issue in Nigeria's agricultural sector, especially in the heat of COVID-19 pandemic. It also focused on the driving factors and the proactive measures that were adopted to tackle the problem. Losses of agricultural produce can occur before, during, or after harvesting. Post-harvest losses focus on the latter and are of great concern to the agricultural sector. Preservation of these produce can be achieved using a regulated and temperature-controlled storage area. Rigid polyurethane (PU), commonly used for insulated chambers, has a very low thermal conductivity coefficient of 0.023W/m.K at 10°C with an average K-value of 1.14m2 k/W per inch, depending on the formulation density. Rigid PU exhibits very good dimensional stability between -180 °C and +140 °C, making it a suitable storage technology to forestall and reduce post-harvest losses of agricultural produce. Nigeria has experienced an unimaginable food loss since the outbreak of the COVID-19 pandemic, threatening food security and precipitating massive importation. This has led to a surge in the country's post-harvest losses, currently estimated at $9billion (N3.4 trillion based on the current official exchange rate of N380) by the Federal Ministry of Agriculture. Post-harvest losses in Africa's most populous nation have been estimated to range between 5% and 20% for grains, 20% for fish and as high as between 50% and 60% for tubers, fruits and vegetables. Losses can be the result of reduction in quality and safety. In the absence of quality packaging and refrigeration systems for controlled temperature, farm produce deteriorate faster while the farmer waits to sell. Vitapur Nig. Ltd., a PU insulation company developed a PU-insulated chamber with a tricycle as its carrier to help forestall post-harvest losses. The designed regulated, PU-insulated chamber helps to preserve the quality of farm produce and the transportation problem is solved using the tricycle as the carrier. The study showed that the PU-insulated chamber, a composite that comprises majorly of rigid PU systems (Polyol and Isocyanate) and chromadek sheets as the facer can help reduce post-harvest losses by almost 27%, depending on the specific design used. [ABSTRACT FROM AUTHOR]

The applicability of structural timber to construction is due to its desirable qualities such as lightweight, aesthetics and eco-friendliness. However, continuous use of timber for structural purposes comes with the challenge posed by the anisotropic nature of various timber species. Advanced societies have developed and modified their sawn timber species in form of glue-laminated structural members such as beams, columns, joist etc. Nigeria timber species are yet to be fully explored along glued-laminated beams production. This paper assesses the suitability of three selected Nigerian timber species namely; Gmelina Arborea (ML), Terminalia superba (AF) and Pycnanthus angolensis (AK) for production of glued-laminated (glulam) beams. They are locally known respectively as Melina (ML), Afara (AF) and Akomu (AK). The applicability and glue-ability of the glues and their ultimate effect on the flexural strength were investigated through the use of two different types of glue components namely; polyvinyl acetate (PVA) and polyurethane (PUR) glue. The physical properties of the timber species such as moisture content (MC) and densities were determined using BS EN 408. The beams produced which are 1680mm by 150mm by 120mm in dimension were subjected to two points loading system to determine their flexural strengths and failure loads in accordance with ASTMD-198. The flexural strengths results indicated that Pycnanthus angolensis offered most resistance to bending loads with an average flexural strength value of 16.04N/mm² when PUR glue was used and 13.04N/mm² when PVA glue was used. The ANOVA result showed that glue types have significant effect on the flexural strength at confidence level of 95%. It was concluded that Pycnanthus angolensis is most suitable for structural applications. PUR is considered the better glue in terms of strength and glue-ability while PVA glue is considered better in terms of workability and applicability based on almost perfect glue line integrity achieved. [ABSTRACT FROM AUTHOR]