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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

A novel approach for the synthesis of graphene oxide silver alginate has been developed for the antibacterial performance. Graphene oxide (GO) was used as a supporting material towards formation of silver nanoparticle (AgNPs) by a rapid microwave irradiation on mixture of GO and silver complexes and layered on alginate film. The obtained nanocomposite were characterized by using Ultraviolet-visible spectroscopy (UV-Vis), Xray diffraction (XRD) to confirm the formation of GOAgAlginate. The surface morphological studies for the nanocomposite was done by using scanning electron microscope (SEM). Nanometer-sized AgNPs (an average diameter of about 70 nm) with spherical-shape structure loaded on the GO Alginate layer showed a good antibacterial towards E.Coli and Methicillin-resistant Staphylococcus aureus (MRSA).

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”.

Laser cleaning has been identified as an ideal technology to replace conventional chemical techniques in the motorcar coating removal process to maintain the sustainability of our environment. This is due to the unique characteristics of this cleaning technique, such as being versatile, precise, controllable, lack of waste generation, and environmental friendly process. This laser technique can remove the coating layers without using chemical products and prevents the metal substrate surfaces from defect. This paper reviews the potential of incorporating pulsed Nd:YAG laser and its principals in coating removal for automotive industry with respect to these characteristics. Keywords: Laser removal mechanisms, Coating system, Ablation, De-composition, Particulate matter

A facile preparation of graphene oxide silver alginate film (GO-Ag) has been constructed for the antibacterial activity. Graphene oxide (GO) was used as a substrate towards arranging of unagglomerated silver nanoparticle (AgNPs) by a simple microwave irradiation on combination of GO and silver complexes in the presence of alginate. The obtained nanocomposite were characterized by using Ultraviolet-visible spectroscopy (UV-Vis) and Xray Diffraction to confirm the formation of film composite. AgNPs with spherical-shape deposited on the GO Alginate layer which displayed a good antibacterial towards E.Coli and Staphylococcus aureus.

This study aims to formulate and characterize a stable nanoemulgel containing Piper betle essential oil as the active ingredient for topical drug delivery. Nanoemulgel is a mixture of nanoemulsion and a gelling agent. Nanoemulsion was prepared by mixing the oil phase that containing soybean oil and Piper betle essential oil at different ratios, tween 80 as the surfactant and glycerol as the co-surfactant with the aqueous phase (distilled water). The essential oil of Piper betle was extracted by using a steam distillation method. The droplet size of nanoemulsion was in the range of 28 to 161 nm. The sizes were confirmed by dynamic light scattering method. Carbopol 940 was used as the gelling agent to increase the viscosity of the nanoemulsion and turn it into nanoemulgel. Nanoemulsion and nanoemulgel were characterised by using the Tyndall effect, spreadability test, and pH test. The pH of nanoemulgel with essential oil was in the range of 7 to 6, which is safe to be used on the skin. Nanoemulgel can be a suitable carrier for the active ingredient (essential oil) to be penetrated with ease into the skin because of its small droplets size. In conclusion, Piper betle nanoemulgel has shown great potential in helping the transdermal delivery.

This paper essentially describes the synthesis of sodium alginate graphene oxide silver (SA-(GOAg)) composite thin film for adsorption of methylene blue. The composite thin film is synthesized using simple solvent casting method by varying the amount of GOAg (20 ml, 40 ml, 60ml, 80ml and 100 ml) into SA solution. The thin film then characterized by using UV-Visible absorption spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. The degradation of methylene blue was observed by using UV-Vis and recorded in every 5 minutes for one hour. The results reveal that the combination of SA and 100 ml GOAg shows the highest adsorption rate in one hour compared to other value of SA-GOAg thin films. The SA-GOAg thin film is believed to have a huge potential in adsorption application such as water treatment.

A series of bimetallic nanocatalysts, cerium/iron oxides supported on the activated carbon (Ce/Fe-AC) were prepared by the impregnation method. Their catalytic activity in the oxidation of organosulfur in commercial diesel were investigated using tert-butyl hydroperoxide (TBHP) as an oxidant. The effect of reaction time, reaction temperature, dopant ratio and calcination temperature were studied to achieve optimum condition for sulfur removal efficiency. The results indicated that the Ce/Fe-AC (80:20) calcined at 400 °C was the most potential catalyst in this study and can remove 91.5% of sulfur under the optimum conditions. X-ray diffraction analysis (XRD) showed that the catalyst was highly amorphous, while micrograph of the field emission scanning electron microscopy (FESEM) illustrated an inhomogeneous distribution of various particle sizes composed of cerium and iron oxides as proven by energy dispersive X-ray analysis (EDX).A series of bimetallic nanocatalysts, cerium/iron oxides supported on the activated carbon (Ce/Fe-AC) were prepared by the impregnation method. Their catalytic activity in the oxidation of organosulfur in commercial diesel were investigated using tert-butyl hydroperoxide (TBHP) as an oxidant. The effect of reaction time, reaction temperature, dopant ratio and calcination temperature were studied to achieve optimum condition for sulfur removal efficiency. The results indicated that the Ce/Fe-AC (80:20) calcined at 400 °C was the most potential catalyst in this study and can remove 91.5% of sulfur under the optimum conditions. X-ray diffraction analysis (XRD) showed that the catalyst was highly amorphous, while micrograph of the field emission scanning electron microscopy (FESEM) illustrated an inhomogeneous distribution of various particle sizes composed of cerium and iron oxides as proven by energy dispersive X-ray analysis (EDX).

A facile synthesis of silver graphene oxide and kenaf cellulose nanofibril (GOAg-CNF) nanocomposite aerogel is reported in this work. The nanocomposite has been characterized using UV-Visible spectroscopy, X-ray diffraction (XRD), Fourier-transform Infrared Spectroscopy (FTIR), Field Emission Scanning electron microscopy (FESEM) and Transmission Electron microscopy (TEM). The objective of this study is to synthesis highly homogenous silver nanoparticle on graphene oxide layer and creating hybrid material in combination with cellulose nanofibril aerogel. GOAg has been synthesized using microwave irradiation method and cellulose nanofibril has been synthesized by bleaching method followed by mechanical disintegration (ultrasonication). The characterization of GOAg-CNF electron microscopy shows the formation of highly homogeneous nanocomposite where the AgNPs are properly distributed on GO and CNF. The average size of AgNPs and CNF obtained is 10 ± 1.9 nm and 14 nm. Subsequently, a mixture of GOAg and kenaf cellulose nanofibril shows very promising properties for future application such as in antibacterial study, water treatment and wound dressing.A facile synthesis of silver graphene oxide and kenaf cellulose nanofibril (GOAg-CNF) nanocomposite aerogel is reported in this work. The nanocomposite has been characterized using UV-Visible spectroscopy, X-ray diffraction (XRD), Fourier-transform Infrared Spectroscopy (FTIR), Field Emission Scanning electron microscopy (FESEM) and Transmission Electron microscopy (TEM). The objective of this study is to synthesis highly homogenous silver nanoparticle on graphene oxide layer and creating hybrid material in combination with cellulose nanofibril aerogel. GOAg has been synthesized using microwave irradiation method and cellulose nanofibril has been synthesized by bleaching method followed by mechanical disintegration (ultrasonication). The characterization of GOAg-CNF electron microscopy shows the formation of highly homogeneous nanocomposite where the AgNPs are properly distributed on GO and CNF. The average size of AgNPs and CNF obtained is 10 ± 1.9 nm and 14 nm. Subsequently, a mixture of GOAg and kenaf ...

To date, various natural dyes were extracted from fruits, leaves, and vegetables were extensively reported with the potential as photo-absorber in dye-sensitized solar cells. In this study, an eco-friendly synthesis of zinc chloride nanoparticles (ZnCl2 NPs) with the extracts of Curcuma longa sp. (turmeric), CL was carried out. The prepared ZnCl2- CL were characterized with a series of analysis such as UV–vis absorption spectroscopy, scanning electron microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FT–IR). It was found that with ZnCl2−CL, UV-vis absorption was shifted and the measured bandgap value was smaller, compared to its starting material. Surface morphology from SEM analysis exhibited the changes of surface morphology and difference in particles size. With smaller bandgap, the conductivity of ZnCl2-CL was found increased from 105.52 eV to 114.52 eV, suggesting that the improvement of photo-absorber properties resulted from mixture solution. With further optimization in the reaction of metal nanoparticles and natural dyes extracts, the tunability of photo-absorber properties and its application in solar cell is believed can bring a promising future for DSSCs.

Laser coating removal is an approach that has the potential to replace conventional chemical-based stripping methods in industry. In addition to the laser parameters, the efficiency of this cleaning technique depends also on the coating system itself. For this reason, we study the influence of the elemental compositions of two Malaysian automotive coated substrates, referred to here as A and B, on laser coating removal mechanisms using the Cynosure Cynergy Nd:YAG laser. The optimum laser coating removal efficiencies for both samples A and B are determined based on the depths of 360 craters obtained using a given formula. Selected crater depths on both of the stipulated samples are then subjected to energy dispersive X-ray analysis to determine their elemental compositions. The results indicate that sample A, which has higher aluminum content, shows greater efficiency in coating system removal, with balanced carbon and oxygen compositions aiding coating reduction during the cleaning process.

A technique to determine the optimum parameters of 30 Watt Continuous Wave (CW) CO2 laser paint removal has been developed on national car coated substrate. This paper reports on the results of studies carried out on two different coating thicknesses; 196 µm and 201 µm using CW CO2 lasers operating at 10, 600 nm wavelength and relatively high beam power from 40%, 50%, 60%, 70%, 80% and 90% out of 30 Watt. Empirical data were presented to demonstrate the optimum power required for paint stripping process. Macro analysis was done to prove the stripping process was in line with the increase of power percentage applied, whereas microanalysis using EDX and SEM revealed the atomic composition and surface roughness of the crater.