Norul Hisham Hamid

The Decay Resistance and Hyphae Penetration of Bamboo Gigantochloa scortechinii Decayed by White and Brown Rot Fungi

The decay resistance and hyphae penetration of bamboo Gigantochloa scortechinii decayed by white and brown rot fungi were investigated using scanning electron microscope (SEM). The bamboo grown in natural stand from three different age classes of 0.5, 3.5, and 6.5 years was harvested, oven dried, sterilised, and exposed to agar media containing 4% malt extract and 2% agar technical (no. 3) under laboratory condition for 8 weeks. The deterioration was expressed as percentage of weight loss, and the decay resistance classes were measured according to ASTM D 2017-81 (1986). This study found that the percentage weight loss was greatly reduced with the bamboo ageing. Regardless of age, the G. scortechinii was classified as highly resistant to decay by white and brown rot fungi. The scanning electron microscope (SEM) observation showed that the fungi hyphae mostly penetrated into the vessel and proceeded to the pit and parenchyma cells.

Characterizations of natural dye from garcinia mangostana with graphene oxide (GO) as sensitizer in dye-sensitizer solar cells

Usage of natural product in improvement of dye-sensitized solar cell (DSSC) have been look upon in research field. There is numerous different type of nature product was used as natural dye but the performance of DSSC with natural dye are low efficiency compare to DSSC with Ruthenium (II) dye due to low anchoring strength between dye molecule with TiO2 surface. This paper is about an experiment DSSC device with sensitizer of Mangosteen with Graphene Oxide as catalyst. The highest device efficiency with graphene oxide (GO) concentration of 0.50 mg/ml obtained in this experiment is 0.40% with short-circuit current density (Jsc) = 1.00 mA/cm2, open circuit voltage (Voc) = 0.61 V and fill factor(FF) = 65.72%. It shows that GO helped to increase device performance by increase the ability of sensitizer absorbed onto TiO2 and adding more passageway for carriers movement between TiO2 surface and dye sensitizer.