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This article reports the activity of natural radionuclides uranium, thorium, and potassium, in different vegetables in Malaysia, measured with a p-type high-purity germanium detector (HPGe). Potassium radionuclides were the most prevalent element in the tested samples, whose activity ranges from 138.89 to 2660.31 Bq/kg. Meanwhile, the activity of uranium was found to be within the minimum detection limit (MDL) to 46.94 Bq/kg, and thorium from

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Infill material in the pipeline repair system works by filling the gap that is usually caused by corrosion before the fibre wrapper can be applied for pipeline recovery. In this study, nanocomposites were prepared by adding a small amount of Multi-walled carbon nanotubes (MWCNT) to an existing commercial epoxy resin grout aiming to evaluate their behaviour regarding neat epoxy grout as infill material in composite repair for steel pipeline subjected to external metal loss. The dispersion of the nanoparticles in the epoxy resin has been conducted through ultrasonic and calendaring technique. The results of modified epoxy grout were compared to neat epoxy grout to identify if the MWCNTs are advantageous to existing materials. By comparing the results, 0.5% of MWCNT filler has significantly improved the strength by almost 53.3%. In addition, the results also indicate that MWCNT filler has increased the modulus of elasticity of the infill material. Furthermore, the morphologies image displayed that MWCNTs has been well merged into the matrix, and made the fracture cross section rougher through sharing the stress. Therefore, it demonstrated the intrinsic potential of the CNTs in modifying the properties of the composites.

Epoxy grout properties are theoretically important in predicting the behaviour of the composite pipeline repair system. Usually, it is used as an infill material to fill the gap or irregularity on the surface caused by pipe corrosion and ensures a smooth bed before fibre wrapper can be applied to recover the pipeline strength. In this research, the existing commercially available epoxy resin grout has been strengthened by using Carbon Nanotubes (CNTs) at the amount 0.1% of weight fractional to evaluate their apropos behaviour to the neat epoxy grout. The various mechanical tests were performed on this modified grout to identify its compression, tensile, flexural and lap shear strength. In addition, the dispersion process of CNTs was carried out by using ultrasonication and three-roll mill technique to ensure an optimum enhancement in the properties of the polymer matrix. By comparing the strength, 0.1% of CNTs filler has significantly improved the strength of grout in flexural, tensile and shear bonding but not in compression. In addition, the results also indicate that CNTs filler has increased the modulus of elasticity of the infill material. Therefore, it demonstrates the intrinsic potential of the CNTs in modifying the properties of the epoxy grout.