Applied Mechanics and Materials Vols. 773-774

Abstract: The purpose of this study is to identify the solid waste generation and compositions that are generated from UNIMAS West Campus area and also to calculate potential energy and profit that can be harvested from the solid waste. This study was conducted at UNIMAS west campus where the samples of solid waste were collected from different types of source of generation namely residential colleges, faculties, Centre Teaching Facilities (CTF) and cafeteria. The solid wastes collected are weighed, mixed, quartered and the compositions of the samples are determined. From the analysis, the solid waste generation rate is 499 kg per day and the major composition of solid waste produced from this study area is food waste with the value of 54% followed by plastic bottle with 9%, mixed plastic with 8%, mixed paper with 7%, box and polystyrene are with 5% and the less percentage of solid waste composition is aluminium with 4%. For the total estimation potential energy that generated by UNIMAS West Campus is about 12819.9 kJ/kg per day and the profit can be achieved when the solid wastes are recycles is about RM 126.43 per day. The analysis shows that solid waste generated in UNIMAS West Campus has a good potential in recycling and give more benefit to UNIMAS. With the data of the solid waste generated in this study area, proper management strategies can be planned by top management of UNIMAS and put it into action in the future. In long term, it will make UNIMAS a green campus which eventually reduces the amount of solid waste generation.

Abstract: Adsorption using activated carbon that decomposed from agricultural waste has been proven to be effective in removing heavy metals in wastewater. This study was carried out to investigate the adsorption of heavy metals wastewater (Lead) using activated carbon that synthesized from the fruit waste which is jackfruit peel. The efficiency of jackfruit peel activated carbon in removing lead from wastewater has been compared to the commercial activated carbon. Result shows that the commercial activated carbon gave better result as compared to jackfruit peel activated carbon (98% of lead removal for commercial activated carbon and 80% of lead removal for jackfruit peel activated carbon). This can be explained from the characteristics of the activated carbon where the commercial activated carbon has a very well develop pores structures in contrast to jackfruit peel activated carbon. In term of isotherm and kinetic study, the Freundlich isotherm model is better fitted in equilibrium adsorption isotherm for jackfruit peel activated carbon and it is favorable adsorption condition. For commercial activated carbon, the Langmuir isotherm is better fitted to the adsorption of lead and monolayer adsorption capacity was found. The experimental data fitted very well the pseudo second order in kinetic model for both activated carbon where the adsorption controlled by chemisorptions.

Abstract: —A new bang of natural gas demand has opened up the opportunities towards the utilization of membrane technology for the purification process.The advantages in terms of smaller footprint, lower weight, minimum utility requirement and low labor intensity make them appropriate for wide scale applications. Polymeric membrane is one of the greatest emerging fields in membrane material development. Nevertheless, the separation performance of the existing polymeric materials were reached a limit in the trade-off between permeability and selectivity. The development of inorganic material gives a significance improvement in membrane performance but it outrageously expensive for many applications and having complicated procedure during fabrication process have limit the application of inorganic membrane in gas separation. Thus, a rapid demand in membrane technology for gas separation and the effort toward seeking the membranes with higher permeability and selectivity has motivated the development of mixed matrix membrane. Mixed matrix membrane (MMM) which incorporating inorganic fillers in a polymer matrix is expected to overcome the limitations of the polymeric and inorganic membranes. Apart from an overview of the different membrane materials for gas separation, this paper also highlights the development of mixed matrix membrane and challenges in fabrication of mixed matrix membranes.

Abstract: Currently, one of the main aspects of health and safety concern to facility owners and supervisors is indoor air quality. Meanwhile, pollution by airborne fungi in these facilities are acquiring more and more consideration due to its possible harmful side effects such as threats to occupiers’ health and damage to building parts and furniture. One of the recommendations to solve these indoor fungi pollution is bioactive compound which can act as a biocide. However, assessment of this compound in the real environment is often time-consuming and impractical. In this study, a bioactive compound, potassium sorbate which is commonly applied in food manufacturing was assessed for its efficiency as a biocide to restrict the growth of an isolated airborne fungus using an in vitro inhibition assay. The fungus was isolated from a new building of tertiary education of computer studies. It was grown on both biocide-incorporated MEA and untreated MEA. The diameter of the fungal colonies was noted time to time. The diameter of the colony of the treated fungus was downsized by 41.25% averagely in comparison with the untreated fungus. It was shown that potassium sorbate can restrict the growth rate of the isolated airborne fungus.

Abstract: In the present work, DDR3 zeolite crystals were synthesized using two different methods. The silica sources used to synthesize DDR3 crystals were tetramethoxysilane (TMOS) and Ludox-40. The resultant samples were characterized using X-ray Diffraction (XRD) and Field Emission Scanning Electron Microscope (FESEM). The XRD results showed that the peaks representing DDR3 structure were not obtained for the sample synthesized in 5 days at room temperature with ultrasonic pre-treatment of 3h using Ludox-40 as silica source. On the other hand, the XRD pattern obtained for the sample synthesized in 25 days at 160 ^o C using TMOS as a silica source were similar with the XRD peaks reported in the literature. From these results, it can be concluded that the synthesis conditions of 25 days at 160 ^o C using TMOS as silica source were the favorable conditions in obtaining DDR3 crystal structure.

Abstract: The Pleurotus spent mushroom compost was selected as biosorbent to sorption Mn(II) ions. The Mn(II) ions biosorption was investigated under batch experiments. The influences of pH, contact time and initial Mn(II) concentration were also investigated. The optimum Mn(II) ions biosorption was achieved at pH 6, 20 minutes of contact time and 10 mg/L of initial Mn(II) concentration using 1.0 g biosorbent dosage. The Mn(II) ions biosorption experimental data were best described by the Langmuir isotherm model and pseudo-second order kinetic model. As conclusion, the Pleurotus spent mushroom compost can be used to sorption the Mn(II) ions from the aqueous solution.

Abstract: Worldwide, cigarette butts (CBs) are among the most common type of litter. The United States Department of Agriculture estimates that in 2004 over 5.5 trillion cigarettes were produced in the world. This is equivalent to an estimated of 1.2 million tonnes of cigarette butt waste per year. These figures are expected to increase by more than 50% by 2025 according to American Cancer Society, mainly due to an increase in global population. This paper presents a review of the environmental problems associated with CBs, which have been found to be the number one littered item in Australia over the past years. It is estimated 25 to 30 billion filter cigarettes are smoked each year; of these, an estimated 7 billion become litter. The CBs accumulate due to the poor biodegradability of the cellulose acetate filter, and the toxicity constituent trapped within threatens human life, marine ecosystems as well as the environment if not disposed in an appropriate manner. With the increasing concern arising from insufficient landfill sites and the growing environmental awareness about toxic incinerator emissions, there is a critical need for an alternative method for CB waste disposal which is environmentally acceptable.

Abstract: Preliminary test was conducted to physically observe and determine the range of Fe and Al concentrations that Scirpus grossus can grow and survive. Pails of 3 L containing 3 kg of sand and 42 days old S. grossus were exposed to different concentrations of Fe and Al solution mixture for 21 days. The mass ratio between Fe and Al in the solution mixture was 3:1. After 21 days of exposure, the plants had shown that they could grow and survive in concentrations up to 300 mg/L Fe + 100 mg/L Al. Effect concentration (EC₅₀) value for single Fe and Al toxicity to S. grossus was predicted between 300 mg/L Fe + 100 mg/L Al and 450 mg/L Fe + 150 mg/L Al. Therefore, it is suggested for the next study of phytotoxicity the Fe and Al concentrations range may start as low as 30 mg/L Fe + 10 mg/L Al up to 450 mg/L Fe + 150 mg/L Al.

Abstract: Good indoor environmental quality (IEQ) is desired for a healthy indoor environment. The microbial growth in indoor environments contribute into poor indoor environmental quality can cause various of health problems. Antimicrobial coatings are designed to generate a surface that is easy to clean and can also incorporate active agents, commonly called biocides, which prevent microbial colonization, the subsequent growth and bio-deterioration of the substrate. The aim for this study is to treat indoor environmental quality in buildings by reviewing the possible application of potassium sorbate used in food industry preservatives to be use as indoor antimicrobial. Plasterboard wall was used as a substrate to see the influence of different common wall finishing used such as paints and wallpapers on fungal growth. Potassium sorbate was tested against fungal isolated from affected room M146, FKAAS building. The total fungal counts in affected room was 806 cfu/m³. The ASTM D5590-00 standard was used to evalute fungal growth and potassium sorbate was effective to inhibit the amount of fungal growth on four common types of wall finishing used on plasterboard wall. As a result, the percentage reduction in growth between control and treatment sample were 10% on thin wallpaper, 15% on acrylic paint, 25% on glycerol-based paint and 60% on thick wallpaper.

Abstract: The preliminary tests is physically and visually observed to estimate the concentrations of contaminants that can give negative effects on plants growth and at which concentration the plants can tolerate and survive. In this study, bulrush of Lepironia articulate was subjected to diesel to assess its ability to survive when exposed to diesel contaminants with different concentrations (0, 5, 10, 20, 30, 35 and 40 mL diesel/L water). The investigation was conducted in 30 days with two flow systems, free surface (FSF) and sub-surface flow (SSF), were adopted to observe in which system the plant can tolerate to diesel better. These findings will be applied in future study of phytotoxicity test to assess its ability to phytoremediate polycyclic aromatic hydrocarbon (PAHs) contamination in wastewater. At the end of diesel exposure, the result indicated that the plant growth in SFS was better compared to FSF system. The plant had shown that it could only grow and survive in concentrations of 5, 10, 20, 30, 35 and 40 mL diesel/L water in SSF and in concentrations of 5, 10 and 20 mL/L in FSF system. The results of this study will be a basis for future study that aims to study PAHs removal from water using L. articulate plants.