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We report a simple and straightforward method for the preparation of graphene oxide-silver aerogel (GOAg) via microwave irradiation. Graphene oxide (GO) was used as a substrate for the growth of silver nanoparticles (AgNPs) and silver complex was used as a precursor. The GOAg were prepared by rapidly expose mixture of GO and silver complexes with microwave for 30 s under an ambient atmosphere. For the nanocomposites, GOAg solution were lyophilized in a freeze-dryer for 24 hours to form an aerogel. The obtained GO and GOAg nanocomposites were characterized by X-ray diffractometer (XRD) and Ultraviolet-visible spectroscopy (UV-Vis). XRD confirmed the formation GO, and GOAg while GOAg display antibacterial properties against Methicillin-resistant Staphylococcus aureus (MRSA) and Aeromonas hydrophila bacteria. We demonstrate

Activated carbon (AC) has attracted attention among researchers due to special properties such as high porosity, highly adsorption and low cost. In this research, activated carbon has been successfully produced from the coconut shell by using the chemical activation which are zinc chloride (ZnCl2), phosphoric acid (H3PO4)and sodium hydroxide (NaOH) as the activating agent. The optimum parameter for the power of microwave radiation used was 380 W, impregnation ratio of activating agent to char was 3: 1 for H3PO4, 2:1 for NaOH, and for 1:1ZnCl2 while concentration of each activating agents was 0.5M. The activation time that were implemented was 10 minutes using microwave radiation method. All samples then characterized using, FTIR, XRD and TGA in order to determine the functional groups, composition and element and weight loss of the activated carbon. The XRD results showed that the activated carbon that had been produced were amorphous. In the FTIR – ATR , the there were C = C bonds and phenyl ring existed in the activated carbons. In TGA results, it indicated that the activated carbon has very high resistant to weight loss compared to char, which range temperature were same. The result showed that phosphoric acid has the most significant effect on the synthesized AC properties since the moisture content was low and the highest yield percentage.

Currently, the primary energy supply in Malaysia is dominant by non-renewable energy sources such oil, natural gas and coal which contributed to the scarcity of these sources and occurrence of global warming. This phenomenon raises the public concerns to diversify the energy sources to sustain energy availability. To address these predicaments, biomass sources is among the prominent alternative energy sources since it is renewable and possesses minimal harms to the environment. Thus, the woody plant with high growth rate and high energy content that can be used to serve as potential biomass energy sources. In this study, small diameter (5-8cm) of wild Acacia mangium species have been determined and compared accordingly three (3) different portions (bottom, middle and top) and two (2) different particle sizes (0.5 and 1.5mm). The analysis conducted to determine the properties of raw material of Acacia mangium as biomass energy sources were proximate, physical and energy content properties. The result obtained for the energy content analysis of small diameter wild Acacia mangium has a mean calorific value range from 16.35 to 18.35MJ/kg between portions and particle sizes. In order to determine the effect of portions and particle sizes on each of the proximate, physical and energy content properties, two-way ANOVA was performed. It shows that both the portions and particle sizes have significant effect on calorific value (energy content) of small diameter wild Acacia mangium at 99% of confidence level. In a nutshell, the biomass energy properties of small diameter wild Acacia mangium with different portions and particle sizes were being determined.

Corbicula fluminea, known as “etak” in Kelantan, Malaysia is a freshwater bivalve. This clam is widely consumed as traditional snack by the locals. However, lately there are numerous reports in local newspapers that claim “etak” to cause health effects due to eating contaminated “etak”. Hence, this study aims to determine the heavy metals concentration in fresh, smoked and exposed “etak” sold at the stall as a baseline study in order to develop a method for removing the heavy metals content in its tissues. This study involves sample collection in the stalls around Kelantan, sample preparations via acid digestion and heavy metal determination using Perkin Elmer PinAAcle 900F Atomic Absorption Spectrometer. The results showed the heavy metals (Cr, Zn, Mn and Cu) concentrations (µg/g) in all “etak” tissue were at different level for fresh (Cr: 1.02±0.35ppm, Zn: 74.57±2.76ppm, Mn: 40.22±9.96ppm and Cu: 15.27±1.41ppm), smoked (Cr: 0.42±0.02ppm, Zn: 54.62±17.83ppm, Mn: 50.13±2.31ppm and Cu: 20.94±8.81ppm) and exposed (Cr: 0.53±0.08ppm, Zn: 63.07±8.44ppm, Mn: 50.41±6.92ppm and Cu: 12.80±0.40ppm) samples. The results obtained were compared with the permissible limits set by Malaysian Food Regulations 1985 (Cu: 30.0ppm and Zn: 100.0ppm), FAO/WHO 1984 (Mn: 5.4ppm) and IAEA – 407 (Cr: 0.75ppm). For fresh “etak”, Zn and Cu concentration were below the standards, while Mn and Cr were exceeded the permissible limits. For smoked “etak” and exposed “etak” at stall, all heavy metals concentration were within the permissible limits, except Mn contents. This study successfully determine the baseline concentration of the heavy metals in “etak”.

Phytoremediation is one of the effective methods in the treatment of water pollutant. In this study,Colocasia esculenta, Pistia stratiotes, and Limnocharis flava were used in this study to remediatethe contaminated aquaculture wastewater. The removal efficiency of parameter elements (Fe, Cd,and P), ability to increase DO, as well as accumulation of parameter elements (Al, Fe and Cd) wereevaluated. Aquaculture wastewater taken from tilapia pond was used as influent to be treated inconstructed wetland reactor tank with the selected plants. The HRT was set as 2 days for each of 6 batches. The plant sample analysis was carried out using Bruker S2 Ranger Energy Dispersive X-Ray Fluorescence (EDXRF) at the beginning and end of the whole set experiments, while the wastewater analysis was carried out using EDXRF and YSI 556 MPS before the experiment andfor each batch. This study has shown the suitability to be used in phytoremediation of aquaculturewastewater was arranged ascending as Limnocharis flava < Pistia stratiotes < Colocasia esculenta.