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Coconut shell (CS) reinforced unsaturated polyester (UPE) composites have been prepared by using hand lay-up and compression molding techniques. To improve fiber matrix adhesion, the CS (30 wt%) was chemically treated by two chemical treatments which are alkaline (NaOH) and alkaline-silane with concentration NaOH (6%) and silane (2%). To enhance the performance of CS-UPE composites, graphene nanoplatelets (GNP) was also added as a nano filler. Scanning electron microscopy (SEM) was used to investigate the morphology of the composite samples. Mechanical properties such as tensile and flexural tests of untreated and chemical treated CS-UPE composites was also studied and compared. Overall, the use of alkalized treated CS-UPE composites showed the best mechanical (strength and modulus). Therefore, alkaline treated CS was selected to be re-prepared with graphene as nano filler in UPE composites at 0.5, 1.0 and 1.5 wt% filler loading, respectively. The presence of GNP in CS-UPE composites have demonstrated a significant enhancement in modulus properties but at the expense of tensile strength. The use of 1.0 wt% of GNP seems more optimize loading since the increment of GNP has reduced the tensile strength, which might be due to the agglomeration issue.

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.

Background: The presence of relatively high naphthenic acid in crude oil may contribute to the major corrosion in oil pipelines and distillation units in crude oil refineries. Thus, high concentration naphthenic acid crude oil is considered to be of low quality and is marketed at lower prices. In order to overcome this problem, the neutralization method had been developed to reduce the TAN value in crude oil. In this study, crude oil from Petronas Penapisan Melaka was investigated. Methods: The parameters studied were reagent concentration, catalyst loading, calcination temperature, and reusability of the potential catalyst. The basic chemical used was 2- methylimidazole in polyethylene glycol (PEG 600) with concentration 100, 500 and 1000 ppm. Cerium oxide-based catalysts were supported onto alumina prepared with different calcination temperatures. Results: The catalyst was characterized by using Brunauer-Emmett-Teller (BET), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetry Analysis-Differential Thermal Gravity (TGA-DTG) to study the physical properties of the catalyst. The Ce/Al2O3 catalyst calcined at 1000°C was the best catalyst due to larger surface area formation which lead to an increment of active sites thus will boost catalytic activity. The result showed that the Ce/Al2O3 catalyst meets the Petronas requirement as the TAN value reduced to 0.6 mgKOH/g from the original TAN value of 4.22 mgKOH/g. Conclusion: The best reduction of TAN was achieved by using catalyst loading of 0.39% and reagent of 1000 ppm.

Radiopharmaceuticals (RPC) used for diagnostic and therapeutic purposes in nuclear medicine may contaminate surface areas due to spillage during its preparation or accident during RPC transfer from laboratory to the treatment room. Fluorine-18 Fluorodeoxyglucose (18F-FDG) is the most common RPC for positron emission tomography (PET) scan in nuclear medicine due to its ideal annihilation converted energy at 511 keV and short half-life at 109.8 min. Ineffective medical waste management of 18F-FDG may pose a risk to the environment or cause unnecessary radiation doses to the personnel and public. Depending on the incident rate of these events, simple decontamination methods such as the use of chemicals and swabs might not be cost-effective and sustainable in the environment. This study aims to propose an alternative method to decontaminate 18F-FDG by using graphene oxide (GO). GO was synthesised using the Hummers method while the physical morphology was analysed using a field emission scanning electron microscope (FESEM). 18F-FDG adsorption efficiency rate using GO nanolayers was analysed based on the kinetic study of the GO:18F-FDG mixtures. The chemical adsorbability of the material was analysed via UV–vis spectrophotometer to interlink the microstructures of GO with the sorption affinity interaction. Resultantly, the adsorption rate was effective at a slow decay rate and the optical adsorption of GO with 18F-FDG was dominated by the π → π* plasmon peak, which was near 230 nm. By elucidating the underlining GO special features, an alternative technique to isolate 18F-FDG for the decontamination process was successfully proven.

Acid hydrolysis method become one of the attention among researcher to produce high degree nanocellulose. Integration of sonication process was used to stir and mix particles in an element for different stages. This paper revealed the surface morphology and crystallinity index of two organic plant that were kenaf and oil palm nanocellulose. Characterization of the nanocellulose were identified by 2 techniques; (1) field emission scanning electron microscope (FESEM) that provides surface morphology and elemental information of the element, (2) x-ray diffraction (XRD) for phase identification of materials crystallinity. The result showed that the properties of nanocellulose increase after sonication method have been integrated.

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).

The naphthenic acids (NAs) present in the crude oil can lead to the corrosion problems in oil refinery equipment apart from reduces the performances of the oil. In this study, the method to remove ...

Objective The objective of this study was to characterize the structure, physicochemical and toxicity properties of Dioscorea Pentaphylla tuber’s starch. Methods Starch was extracted from Dioscorea Pentaphylla tuber’s and analyzed to determine their properties such as pH, water binding capacity, solubility, swelling power, chemical composition, thermal properties, degree of crystallinity, morphology and toxicity. Results Results showed that more than half of Dioscorea pentaphylla starch consist of amylose (64.10 ± 1.15%). It has gelatinization temperature started at 76.90 ± 0.08 °C. This C-Type starch has a degree of crystallinity around 32.90 ± 2.59%. The SEM image showed that Dioscorea pentaphylla has oval-shaped particles with sizes ranging from 42 to 55 µm. The toxicity test demonstrated that the starch was safe and can be classified as non-toxic. Conclusion The physicochemical and toxicology properties of Dioscorea Pentaphylla starch recorded in this study indicate that this starch is applicable as biopolymer source for food and non-food purposes.

The presence of organic dyes from industrial wastewater can cause pollution and exacerbate environmental problems, therefore, in the present work, activated carbon was synthesized from locally available oil palm trunk (OPT) biomass as a low-cost adsorbent to remove synthetic dye from aqueous media. The physical properties of the synthesized oil palm trunk activated carbon (OPTAC) were analyzed by SEM, FTIR-ATR, and XRD. The concurrent effects of the process variables (adsorbent dosage (g), methylene blue (MB) concentration (mg/L), and contact time (h)) on the MB removal percentage from aqueous solution were studied using a three-factor three-level Box–Behnken design (BBD) of response surface methodology (RSM), followed by the optimization of MB adsorption using OPTAC as the adsorbent. Based on the results of the analysis of variance (ANOVA) for the three parameters considered, adsorbent dosage (X1) is the most crucial parameter, with an F-value of 1,857.43, followed by MB concentration (X2) and contact time (X3) with the F-values of 95.60 and 29.48, respectively. Furthermore, the highest MB removal efficiency of 97.9% was achieved at the optimum X1, X2, and X3 of 1.5 g, 200 mg/L, and 2 h, respectively.

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”.

The bimetallic copper with manganese (Cu/Mn) on alumina (Al2O3) support have been considered as potential catalyst for the carbon dioxide methanation due to the low cost and its unique ability to facilitate the conversion of carbon dioxide (CO2) to methane gas (CH4). However, high operating reaction temperature limits their large scale industrial application. In order to address this challenge, a series of low ruthenium (Ru) content promoted on Cu/Mn supported onto Al2O3 have been design by wet impregnation method. The potential catalyst was tested catalytic acitivity by using single and double reactors. The influences of Cu/Mn ratios and Ru contents on the catalytic activities and physicochemical properties of prepared catalysts were investigated. The addition of Ru can improve the catalytic activity and the basicity of the catalysts surface. As a result, their low-temperature reaction had been enhanced over these doped Ru promoted catalysts. The optimal catalyst was 3Ru60Cu/Mn-Al2O3 where the CO2 conversion reached 98.2% with the methane selectivity of 100% at 220 °C by using single reactor. Interestingly, the reaction temperature was reduced at 170 °C when using double reactor which the CO2 conversion reached 95.6% with the methane selectivity of 100%. The stability test showed that the Ru promoted on Cu/Mn-Al2O3 catalyst maintained its high reactivity after 7 h.

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

The catalytic activity of carbon dioxide (CO2) methanation by in situ hydrogen generated from aluminum foil (Al) and alkaline water over a novel catalyst (AHZ–CM) was investigated. Response surface method- ology involving Box–Behnken design (RSM-BBD) was implemented for optimization where the reaction temperature was found to be the utmost significant effective factor, followed by H2/CO2 ratio and weight catalyst loading. The optimum condition for CO2 conversion was at 3.29g of weight catalyst loading, H2/CO2 ratio of 4.08 and reaction temperature of 276.7 °C which resulted in 97.5% of CO2 conversion. The result was approximately in agreement with the predicted result found by RSM which achieved 99.9% CO2 conversion. Interestingly, this study proved that the hydrogen gas production from Al and alkaline water can be used in situ reaction and the novel catalyst (AHZ–CM) would be an excellent candidate to be used for CO2 methanation reaction.

This research was targeted to use the planetary ball milling method to extract cellulose nanofibers (CNFs) from commercial microcrystalline cellulose and also to utilize the obtained extracted cellulose nanofibers (CNFs) as reinforcement in polyvinyl alcohol (PVA) thin film. The effect of cellulose nanofibers (CNFs) on the mechanical and physical properties of polyvinyl alcohol (PVA) thin films was investigated. As a result of the study, we found that the thin film’s tensile strength is good, and the surface morphology of the CNFs suspension enhances the bonding between the PVA and the reinforcement. Tyndall effect was accurate with the visible light scattering through CNF suspension, and the CNF/PVA thin film exhibited transparent thin film. In contrast, the CNF/PVA composite’s mechanical and physical properties are good due to the excellent dispersion and absence of agglomeration of CNFs. The prepared PVA/CNF biocomposite would be a suitable candidate to be implemented as biodegradable food packaging material.

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.

Radon (222Rn) is radioactive gas emanates from soil, rock sand and enter the building through cracks, construction joint, gas in suspended floors and also from the building materials itself. 222Rn gas in high concentrations is hazardous as it can affect the human organ and tissues due to the emission of alpha particles. This study aims to determine the outdoor and indoor 222Rn concentrations in academic building, Universiti Malaysia Kelantan (UMK) Jeli Campus as well as to identify any possible factors influenced the gas progenies. Radon Sentinel 1030 was placed in open space between the lecturer’s rooms and inside closed room (Lecture Hall 4) on the first floor of the building for data collections. The total of 224 data of 222Rn concentrations reading has been collected for outdoor and indoor spaces with 0.5 hours time interval. The outdoor and indoor 222Rn concentrations were found in ranges between 0.23 pCi/L to 0.48 pCi/L and 0.73 pCi/L to 1.13 pCi/L, respectively.

The objectives of this study are to briefly monitor the 222Rn concentration in selected study area and to investigate its correlation with the environmental factors (pressure, humidity and temperature). 222Rn concentrations were monitored in three different sizes of lecture rooms known as BK 6, BK 7 and BK 8 at academic building, Universiti Malaysia Kelantan (UMK) Jeli Campus. Radon monitor known as Sentinel 1030 has been used to collect 210 readings of 222Rn concentration data. Environmental factors for each study areas was analyzed by using Pearson correlation. The average 222Rn concentrations for BK 6, BK 7 and BK 8 were found at 0.29 pCi/L, 0.31 pCi/L and 0.72 pCi/L, respectively. BK 8 with 277.97 m³ obtained higher 222Rn concentrations than BK 6 with 440.98 m³, followed by BK 7 with 292.67 m³. From the results, 222Rn concentration in BK 6 and BK 7 are influenced by temperature and pressure, correspondingly. However, no correlation of environmental factors found in BK 8.

Highly continuous exposure to Radon (222Rn) concentrations can affects human health and cause lung cancer. This study aims to briefly monitor 222Rn concentration at different level altitude and to investigate correlation between their environmental parameters sort of temperature, humidity and pressure in indoor space. Lecture rooms known as BK 4 in the first floor and BK 8 in the third floor at academic building Universiti Malaysia Kelantan (UMK) Jeli Campus were selected as the study areas. The total of 210 readings indoor 222Rn concentrations data have been collected for the whole study using Radon Sentinel Model 1030. Average 222Rn concentration in BK 4 and BK 8 were found to have range from 0.36 pCi/L to 0.73 pCi/L and 0.40 pCi/L to 0.93 pCi/L, respectively. 222Rn concentration is higher at BK 8 with height 14.4 meter than BK 4 with height 4.8 meter from the ground. Negative correlations were obtained between 222Rn concentrations over pressure, temperature and humidity at BK 4. Meanwhile, 222Rn concentrations over pressure and humidity at BK 8 have shown positive correlation and negative correlation with temperature.

Study of dye removal by using activated carbon in dialysis tube method was studied in order to determine the effectiveness of this method. Three different parameters namely activated carbon dosage, temperature and contact time were evaluated. Characterization of the activated carbon was realized by Scanning electron microscopy (SEM) to observe the morphology of the activated carbon. Based on the obtained results, the performance of the activated carbon in the presence of dialysis tubing method was explained.

Water is essential to the ecosystem for the energy required to stay alive. Nowadays, rapid development in technology can cause pollution to the environment such as water quality pollution and then faced by society. A dangerous source in wastewater such as dyes poses a severe problem due to its toxicity and it was hard to treat. Based on the adsorption ability, activated carbon from corn cob was made for the removal of dyes in wastewater treatment. Activated carbon from corn cob was developed by using alkaline solution treatment of potassium hydroxide (KOH) with different mass ratios, and then was characterized by FTIR, XRD, and SEM. The synthesized activated carbon was also used for removal of methyl orange from aqueous solution. In this research, the obtained char yield after pre-carbonization at 500 °C was 74.20%, while activated carbon yields were 53.60% to 78.80%, based on its difference mass ratios of KOH. The activated carbon without an activation agent gave adsorption capacities of 14.63%. However, when the char was introduced to KOH, the adsorption was increased from 41.09% to 80.36%. The percentage of dye removal increased when the mass ratios of KOH increased. The produce activated carbon from corn cob by using KOH can be effectively used for wastewater 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 ...