Development and Evaluation of the Mechanical Properties of Coconut Fibre Reinforced Low Density Polyethylene Composite

This research work developed and evaluated the mechanical properties of coconut fibre reinforced low density polyethylene (LPDE) composite material. The effect of fibre loading on the mechanical properties: tensile, flexural, and impact of the developed composite material have been investigated. Also carried out was the effect of fibre loading on the water absorptivity of the developed material. Sample categories of the developed composite were prepared by varying the fibre contents by weight at 0%, 10%, 20%, and 30%. The aim is to reduce the excessive waste disposal of LDPE materials that are largely found in the form of disposed water package materials (or pure water sachets) that usually affects the environment in the form of pollution. The water retting process was applied in extracting and cleaning fibre (or coir), while the mixed coir-LDPE (or developed composite material) was prepared by Compression Moulding Technique (CMT). The tensile and flexural properties were tested using Hounsfield Monsanto Tensometer (type w) while the impact properties were tested using the Charpy Impact testing machine. The microstructure of the composite was investigated using Scanning Electron Microscopy (SEM). The fractured surface morphology of the composite samples indicated a homogeneous mixture of the coir fibre and LDPE matrix. However, weak interfacial bonding between the coir fibre and LDPE matrix was also observed. The analysis of the water absorptivity showed that the developed composite materials have low water absorptivity at low fibre loading. However, at higher fibre loading, the water absorptivity increases significantly.

The Influence of Heated Soil in Crop of“Tamaris”Tomato Plants on the Biological Activity of the Rhizosphere Soil

The aim of this study was to evaluate the effect of heated soil on the population of bacteria, fungi and nematodes inhabiting the soil of tomato cultivar “Tamaris” growing in peat and coconut substrates. In addition, these media were tested in two different containers: cylinders and slabs. The total number of bacteria and fungi was significantly higher in the peat substrate than in the coconut substrate. A much higher number of beneficial bacteria producing spores were noted in the coconut soil. The total number of bacteria and fungi was modified by the heating levels. In all the experimental treatments, most of the identified individuals belonged to the group of nematodes that feed on bacteria and it was the most diverse group of species. The highest total number of nematodes was recorded for the second heating level, with the exception of cultivation carried out in peat slabs, where the most of nematodes were found at the control level. The highest first crop was produced by plants growing on the peat slabs supplied with the highest soil temperature. Tomato roots of all the control treatments showed the highest root morphological parameters.