Paper wastes accumulating in the environment are posing an ever increasing ecological threat. This study aimed to isolate soil bacteria closely associated with the bacteria degrading waste paper. A total of six soil samples were collected from dumped soil hostel garden at Universiti Teknologi MARA, Shah Alam. Bacillus, Aspergillus and Micrococcus species were found to be the most widely distributed on the entire sample taken. Six cultures were screened for the ability to degrade cellulose. Bacillus was identified as only bacteria isolated that can degrade paper at highest production of glucose compared to others. The efficacy of microbes in the degradation of paper was analyzed in broth culture fermentation within 7 days incubation. This work reveals that Bacillus subtilis,Bacillus spp and Micrococcus spp posses great potential to degrade paper. In contrast, Acinetobacter spp react very slowly in degrading the waste.

Composite catalyst ZnO/TiO 2 of molar ratio 0.75% was synthesized via sol gel method. The effect of preparation method on the crystal morphology was investigated. The catalyst particles were calcinated at 500 o C,550 o C and 600 °C for 3 hours. The XRD results revealed that calcination temperature controls the crystalline phase in terms of homogeneity and surface area of catalyst produced. The particle size was found to increase with calcination temperature suggesting the effect of different calcination temperatures on catalytic activity for complete degradation of phenol. The result found that ZnO/TiO 2 catalyst calcinated at 600 o C resulted in 70% phenol degradation within five hours of irradiation time under visible light. The kinetic behavior of phenol degradation was found to fit with pseudo first order Langmuir-Hinshelwood kinetic model. Keywords: sol gel, ZnO/TiO 2 catalyst, photocatalytic degradation, visible light, kinetic Abstrak Pemangkin komposit ZnO/TiO 2 dengan 0.75% nisbah molar telah di sintesis melalui kaedah sol gel. Kesan kaedah penyediaan pada morfologi kristal itu telah di selidiki. Zarah-zarah pemangkin telah dikalsinkan pada suhu 500 o C, 550 o C dan 600 o C selama 3 jam. Keputusan XRD menunjukkan suhu pengkalsinan mengawal fasa kristal dari segi kesamaan dan kawasan permukaan pemangkin dihasilkan. Saiz zarah didapati meningkat sejajar dengan peningkatan suhu pengkalsinan mencadangkan kesan suhu pengkalsinan yang berbeza pada aktiviti pemangkin untuk penyingkiran penuh fenol. Keputusan mendapati pemangkin ZnO/TiO 2 yang dikalsinkan pada 600 o C boleh menyebabkan 70% fenol terdegradasi bagi tempoh lima jam masa penyinaran di bawah cahaya nampak. Kelakuan kinetik degradasi fenol didapati sesuai dengan pseudo peringkat pertama model kinetik Langmuir -Hinshelwood.

Recent previous studies have shown that there is a correlation between heat conductivity and surface materials. In this project, the heat conductivity 3 different samples of T2 copper with different surface roughness was studied. This was done by measuring the temperature of the samples at 9 different point using SOLTEQ Heat Conduction Study Bench (Model HE106). The surface roughness of the different samples was achieved using sandpaper and measured using the (SURFTEST SJ-410) where the different surface roughness was A: Ra=0.379μm, B: Ra=0.71μm, C: Ra=0.053μm. The sample was heated using a heater with 10W of power. From the collected data, it was observed that the specimen with the smoothest surface roughness has the best performing heat transfer with the specimen C that have the highest decreasing percentage temperature followed by specimen B and specimen A.

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