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Biocomposites sheets were prepared by compression molding from mixtures of corn starch plasticized by glycerol as matrix and cellulose fibers, extracted from used office paper, as reinforcement filler with contents ranging from 0 to 8% wt/wt of fibers to matrix. Properties of composites were determined by mechanical tensile test, differential scanning calorimetry, thermogravimetric analysis, water absorption measurement, and scanning electron microscopy. The results showed that higher fibers content raised the tensile strength and elastic modulus up to 109% and 112%, respectively, when compared to the non-reinforced thermoplastic starch (TPS). The addition of the fibers improved the thermal resistance and decreased the water absorption up to 63.6%. Scanning electron microscopy illustrated a good adhesion between matrix and fibers.

This study was carried out to investigate the effect of beating process to the characteristics of pulp and paper produced from oil palm oil male flower spikes (OPMFS). OPMFS pulp was prepared according to chemical Soda-AQ pulping process. 60 gsm handsheet of oil palm male flower spikes paper were prepared from OPMFS pulp with four different beating times which are 0 revolution, 1000 revolutions, 2000 revolutions and 3000 revolutions. All physical and mechanical characteristics were investigated according to TAPPI and MS ISO standards. The results show that overall physical and mechanical characteristics of POMFS paper were influenced and enhanced by beating process between 0 until 3000 revolutions. This research demonstrate some potential characteristics of palm oil male flower spikes (OPMFS) paper to be investigated as a newly explored non-wood based raw material for papermaking raw material for papermaking.

Current pulp-processing in pulp and paper based industries are inefficient in removing the lignin as this compound is recalcitrant towards degradation. Transitioning from conventional pulping process into bio-delignification through utilisation of ligninase enzymes is one of the alternatives to improve the ability to fully utilize all components of wood to produce high quality fibres. Extensive research efforts have been focused on increase the production of ligninase enzymes from white rot fungi as a whole organism for industrial applications. However, enzymes activity produced from fungi are rather low as lignin modification is a secondary metabolism in which the enzyme only be expressed under particular conditions. Using genetic manipulations to incorporate genes associate for delignification isolated from different organisms such as tropical Asian wood-feeding insect into bacteria expression system will allow rapid enzyme production. This theoretical framework aims to produce an enzyme with high ligninase activity that will be used for removal of lignin during pulp-processing. These enzymes are thought to be more economically efficient in degrading lignin and involves less use of chemicals thus make this processing more environmentally friendly.Keywords: Biodelignification, Asian wood tropical insect, fungi, ligninase enzyme, bacterial expression system

This research studied the electricity production from organic wastes fermentation by microbial fuel cell by using a single chamber microbial fuel cell (SCMFC). Two sizes (1 L and 10 L) of simple SCMFC were fabricated by using a cylindrical plastic tank which anode compartment and cathode compartment separated by plastic plate with hole and covered with cotton fabric. The anode electrode contacted with organic matter and microorganisms where anaerobic reaction occurred to generate electron and proton. The electrons transferred through an external circuit while the protons diffused through the solution to the cathode electrode for reducing oxygen to water. From the study of the effect of different electrode types (carbon graphite rod, zinc metal, and copper metal) to the electricity generation using the SCMFC size 1 L in fermentation with synthetic sweetness solution (22%Brix) and the effective microorganism (EM) for 36 hrs, it found that the fuel cell which used copper metal as electrode produced electricity increasing over the times and has more efficient than the other electrode types. The study of electricity generation from organic waste fermentation by using the SCMFC size 10 L and using copper metal as electrode, the results showed that the fermentation of pineapple waste produced the current density, potential density, and power density higher than the fermentation of bananas and the fermentation of food garbage with EM. An optimal period of time for the production of electricity from this microbial fuel cell is the first five days of fermentation that the cells has voltage »500 mV, the current density 25.52 mA m-2, potential density 104.69 V m-2 and power density 12.59 mW m-2, and then decline over time five days (120 hrs). Moreover the bio-liquid fertilizer and the residues from the fermentation can be further used in agricultural because of the nutrient content (N, P, K), organic carbon and organic material contents available.

Biomediated soil improvement, a promising new branch of microbial geotechnology; which involved multi disciplines has successfully attracted abundant attentions among researchers, geotechnical engineers, and other industries practitioners. Few of the researches were conducted to examine the potential implementation of this technique on tropical residue soil. However, the uncertainties outcomes and inconsistency of bio mediated soil improvement, especially on the clayed soil have made this technique remained at the laboratory stage. Therefore, this paper intended to provide better understanding of this technique by investigating the relation between the bacteria, cementation reagents, and tropical residue soil. The residual soil was mixed with facultative anaerobe bacteria, Bacillus Subtilis before it was compacted into a prefabricated PVC mould. The soil samples were treated with different treatment condition such as (1) control or untreated, (2) treated with cementation solution, (3) treated with bacteria only, and (4) treated with bacteria and Cementation reagent. A worth noting finding showed that the sample treated with bacteria and nutrient only has produced the highest increment of shear strength. This phenomenon might have been caused by the effect of the chemical reagent to the mineralogy of residue soil. The presence of the chemical reagents is believed to have weakened the shear strength of the tropical residual soil.

Malaysia has an abundance of agro waste material that have not been fully utilized to a maximum production. Thus, the finding of a new alternative fiber in non wood material will be favorable in paper production. Pineapple (Ananas Comosus) is the common tropical plant, which consists of coalesced berries. This pineapple is leading member of the family of Bromeliaceae and it came from genusAnanas. Fiber bundle from pineapple leaf can be separated from the cortex where it reveals the pineapple leaf fiber in multi-cellular and lignocelluloses pattern. This leaf has a ribbon-like structure and cemented together by lignin, pentosan-like materials, where it contributes to the strength of fiber [7]. All parts in pineapple from fruits to leaves could be consumed to give a health benefit for human life. Pineapple had been used as textile fiber, anti-inflammatory and also anti-helminthic agent. According to the FAO online database, the Malaysian country had consumed 255,000 tones per year and in third position in the world of consuming pineapple production. Pineapple is mainly produced as canned fruits and also coarse textiles in some Southeast Asian countries. Leaves of pineapple had been used as coarse textiles because of the fiber composition and structure inside the leaves [3]. All fibrous in non wood materials especially pineapple leaf consists of cellulose, holocellulose, hemicelluloses and lignin along with some extraneous material called extractives such as gum and resin. Previous research indicates pineapple leaf fiber contained higher cellulose content than wood fiber. Pineapple leaf fibers also consist of lignin [23], an adhesive component that binds the cellulose and hemicellulose. Pineapple leaf fiber had the lowest lignin content than other alternative fiber, which is favorable during chemical processing [12]. The chemical composition aspects have been considered in the previous literature, such as banana stem, coconut and oil palm and had been reported extensively. Pineapple leaf reported has a lowest lignin (10.5%) rather than banana stem (18.6%), oil palm (20.5%) and coconut (32.8%) that suggest can undergo bleaching more easily and have high fiber strength [12]. Besides that, pineapple leaf contains high holocelulose content (87.6%) than banana stem (65.2%), oil palm (83.5%) and coconut (56.3%) [11]. Those properties depend on the content of chemical composition in the pineapple leaf fiber, which is cellulose, hemicelluloses and lignin content [15].

Microbial fuel cell (MFC) represents a new method for producing electricity from the oxidation of organic matter. In addition, MFC offers an effective wastewater treatment. The feasibility of using POME wastewater as a substrate was investigated through a two-chambered MFC operated in batch mode for 12 days. The performance of MFC was evaluated under three different anode pH microenvironments of acidic (pH 4), neutral (pH 7) and alkaline (pH 8). Results of experiments indicated that the MFC reactor was able to generate electricity and treat POME wastewater that acted as substrate for MFC. The performance of MFC was found to be dependent on the anode pH microenvironments. Higher power density was observed at neutral condition compared to acidic and alkaline conditions. Furthermore, significant reductions in chemical oxygen demand (COD) in anode chambers were found due to the changes of pH in anode microenvironment. This indicated that effective wastewater treatment of POME in MFC batch experiments. In conclusion, MFC provides an alternative, sustainability and effective method to generate electricity and effectively treat wastewater.

Malaysia is located on the equator has resulted in having two seasons wet and dry. Both of the seasons can influence indoor air quality of buildings promoting the growth of fungal. Fungal growth can occur with the combinations of temperature, relative humidity, substrate and others. Indoor and outdoor air quality is essential for building occupants to prevent the infection diseases caused by fungal. The goal of this study is to remediate the growth indoor fungal after treated with biocides on different types of wall finishing and evaluate the efficiencies of biocides to treat indoor fungal. In this study, the biocides are utilized as a coating for coating bio-resistance. The measurements of the fungal growth are made by growing the samples on realistic wood substrates on the different wall finishing such as paints and wallpapers. The mold that grew are affecting most of the rooms is selected. The air sampler that have been used to isolate the samples of indoor fungal according to NIOSH Manual Analytical Method (NMAM 0800), a guideline provided by National Institute of Occupational Safety and Health (NIOSH). The fungal growth was evaluated using the ASTM D5590-00 standard measuring on the surface of substrate. The results show that potassium sorbate as biocide was able to reduce the indoor fungal growth depending on the type of material used in the building.

The process of combustion in coal fired power plant generates ashes, namely fly ash (FA) and bottom ash (BA). In addition, coal ash generated from coal combustion generally contains heavy metals within their compositions. These metals are toxic to the environment as well as to the human health. Fortunately, treatment methods are available for these ashes and the use of FA and BA in concrete mix is one of the few. As such, this study presents the work in determining the leachability of self-compacting concrete (SCC) incorporated with FA and BA. The ashes were obtained from Kapar Energy Ventures power plant in Kapar, Selangor. SCC mixtures incorporated with 10%, 20% and 30% FA (replacing cement) and BA (replacing sand) respectively was formulated and casted. The samples were then crushed to be extracted using Toxicity Characteristic Leaching Procedure (TCLP) and heavy metals content within the samples were identified accordingly using Atomic Absorption Spectrometry (AAS). From the results, it was found that incorporation up to 30% of the ashes were safe as the leached heavy metals concentration did not exceed the regulatory levels, except for arsenic (As). On the other hand, incorporation of 20% FA and BA each in SCC provided the most economically viable product, with high strength and low leachate concentrations. In conclusion, this study will serve as a reference which suggests that FA and BA are widely applicable in concrete technology and its incorporation in SCC constitutes a potential means of adding value with appropriate mix and design.

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.

The wet market wastewater may lead to pollution, odour and aesthetic problems to the environment and society if not treating properly. Thus, this research was conducted to culture microalgae Scenedesmus sp. and to identify the optimal concentration of microalgae Scenedesmus sp.due to the nutrient and heavy metal removals from wet market wastewater based on laboratory scale. The samples were taken from Public Market Parit Raja, Batu Pahat at 9a.m. in the morning using grab sampling technique. The characteristics of raw wastewater and microalgae Scenedesmus sp. were determined. There are five sample wastewater (used 625ml for each five sample wastewater) with five different sample concentrations of microalgae which are 6.50x105, 49.88x104, 34.75x104, 19.63x104 and 49.88x104 cell/ml with 16 days as duration for period study. The microalgae were cultured by BBM for eight days and another eight days for treatment with replicates three times for each sample. The analysis were measured due to the nutrient and heavy metal removals which are TN, TP, TOC, Fe and Zn during eight days treatment process. Based on experimental result, the optimum efficiency removals for each concentration were achieved 45.6-86.4% of nutrients and heavy metals removal. The highest amount of nutrient and heavy metal removals after wastewater treatment by microalgae are TN 74.77%, TP 82.17%, TOC 86.36%, Fe 65.76% and Zn 84.14%. As conclusion for this experiment, Sample 2 (concentration 49.88x104 cell/ml of microalgae Scenedesmus sp.) is the optimum concentration due to the highest percentage of nutrients and heavy metals removal which achieved 65.3-82.1% which TN 65.32%, TP 76.77%, TOC 80.34%, Fe 65.76% and Zn 82.12%.

Dairy wastewater are usually much polluted due to the high level of nutrient content such as phosphate, nitrate, sulfate etc. The pollution level are indicated by few characteristics such as BOD (243 mg/L), COD (324 mg/L), pH (9.08), Total Nitrogen (65.06 mg/L), Total Organic Carbon (143.3 mg/L), Total Carbon (312.9 mg/L) and Inorganic Carbon (169.6 mg/L). In this study, Botryococcus sp., a species of green microalgae are used to determine whether it can purify dairy wastewater. In spite of that, the microalgae growth over phycoremediation process also determined daily based on hemocytometer counting. From 100% concentration of dairy wastewater, Botryococcus sp. was capable to reduce the parameters such as BOD of 73.3%, TOC of 65.1%, TC of 61.4%, IC of 58.3% and COD of 48.8% on the 15 days of phycoremediation. Meanwhile, for the 50% of dairy wastewater, the same microalgae be able to remove the parameter such as phosphate of 78.7%, BOD of 73.8%, TOC of 70%, TC of 68,8%, IC of 59.4% and COD of 50%. The overall result from this study shown that the Botryococcus sp. is useful to reduce the inorganic and organic pollutant in dairy wastewater and could be potential to be used for any different wastewater.

As the key process of weaving, sizing is one of the processes which are of great costly and serious pollution in the whole cotton-textile production chain. Great efforts had been made to study new sizing to reduce costs and environment pollution. In this paper, Methyl cellulose ether (MC) and hydroxypropyl methyl cellulose ether (HPMC) were prepared by the hemp core and further used as a textile sizing. The chemical structure of the hemp cellulose ether was characterized by the FTIR analysis. The paste viscosity was tested by the Viscometer. The sizing properties of hemp cellulose ether were evaluated by the weaving process. The results indicated that the wrap breakage rat, weft breakage rate and loom efficiency of MC and HPMC blended sizing was similar to those of PVA sizing. Compared to COD in the desizing wastewater of 3600 mg/L of PVA, the COD of hemp sizing was very small. It was 330 mg/L. Therefore, it is concluded that the hemp core ether is a new and environment-friendly textile sizing, which has low cost and contributes a healthier ecosystem.

Nowadays, consumers are concern about the quality of water that being supplied in order to ensure the water supplied is free from any harmful substances for example like Humic Substances (HS). High concentration of HS in drinking water can cause disease for human such as stomach cancer. Thus, it is important to develop a new technique to improve the quality of drinking water. Therefore, the objective of this research is to investigate the potential of using coconut copra treated with citric acid as activated carbon in adsorbing HS contained in wastewater collected from Asajaya Treatment Plant situated in district of Samarahan, Sarawak. In this research, the optimum condition of adsorption process need to determined. As such, there are two types of parameters which are considered as constant; temperature and pH of activated carbon and variable; solid liquid ratio and residence time. As a result, this research has shown that coconut copra possess the capacity to adsorp 97.5% of HS contained in wastewater.

Biomass processing using low transition temperature mixtures (LTTMs) has the potential to become a sustainable alternative resource for production of raw materials and fuels with a neutral carbon dioxide balance. The state of art for customizing the physicochemical behaviour of these new green solvents by a prudent selection of the constituents’ nature and ratio through microwave irradiation is presented in this work. The impact of the following parameters, namely type of malic acid, molar ratio of malic acid to natural salt, water content and temperature of treatment are related to the solvation behaviour of LTTMs. An overview of the conditions for the highest efficiency in the delignification of empty fruit bunch (EFB) are described.

This paper presents the simulation of the flexible aerator model as a new concept to generate dissolved oxygen. This method is implementing the flexible beam motion as a medium to circulate water and create wave. This paper is using the simulation to optimize the suitable parameters namely the length of flexible beam and the percentage of immerse in water. The best result of dissolved oxygen level were found during run the flexible beam aerator at 12 V with 0.65m length of flexible beam and immerses 25% in water. The flexible beam was successfully implemented as a new aerator concept where it is able to generate oxygen up to 8.6mg/L with the average Standard Oxygen Transfer Efficiency 1.84 kgO2/kWhr

The use of biopetrol fuel as alternative fuels in gasoline engine has been around for many years and Ethanol-petrol has the potential to be used as alternative fuel that can reduce the total CO2emission from internal petrol engine. However, the changes of bio-petrol is a very complex and need further understanding for researchers due to the relevance of the increase in the petroleum price and the future environmental regulation. This review paper focuses to ascertain a new approach in potential on ethanol-petrol blends operating with a petrol engine especially the effects of ethanol gas petrol blending ratio and variant types of ethanol on performance and emissions of petrol engine. It is shown that the variant in biopetrol blending ratio and engine operational condition are reduced engine-out emissions and increased efficiency. This paper presents on a review on three different types of ethanol like sugar cane, wheat and corn with various blended rates. Investigation framework study on how to complete the research is also included in this paper.Keywords: biopetrol, petrol engine, performance, emissions, biopetrol fuel properties

The use of biopetrol fuel as alternative fuels in gasoline engine has been around for many years and Ethanol-petrol has the potential to be used as alternative fuel that can reduce the total CO2 emission from internal petrol engine. However, the changes of bio-petrol is a very complex and need further understanding for researchers due to the relevance of the increase in the petroleum price and the future environmental regulation. This review paper focuses to ascertain a new approach in potential on ethanol-petrol blends operating with a petrol engine especially the effects of ethanol gas petrol blending ratio and variant types of ethanol on performance and emissions of petrol engine. It is shown that the variant in biopetrol blending ratio and engine operational condition are reduced engine-out emissions and increased efficiency. This paper presents on a review on three different types of ethanol like sugar cane, wheat and corn with various blended rates. Investigation framework study on how to complete the research is also included in this paper.Keywords: biopetrol, petrol engine, performance, emissions, biopetrol fuel properties

The solidification/stabilization (S/S) is one of the effective methods that are used for the heavy metals treatment. It was known that one of the main issues of this method is that the heavy metal is stayed inside the matrices, not destroyed nor adsorbed, which may cause serious problems for the environment once the matrices would be crashed. Agricultural wastes have shown a great capacity to the heavy metal adsorption from solid and liquid wastes. This paper reviews the incorporation of the agricultural wastes as heavy metals' adsorbents inside the matrices of the S/S method. In addition, changes in particle sizes, pre-treatment, temperature and other factors have also been discussed towards the heavy metal adsorption. Nevertheless, research regarding the incorporation of the agricultural wastes into the S/S method is very minimal, and almost all the previous researches were only focusing comprehensively on the leaching characteristics of the method. Introduction.Nowadays, Industrial production leaves enormous quantities of mineral wastes accompanied with toxic heavy metals like Cd, Hg, As and Pb. These heavy metals are generally considered the most toxic to humans and animals, without any beneficial effects to them. Thus, they may cause acute diseases for the human beings such as dullness, restlessness, irritability, anemia, neurological effects and others (1). Several methods have been conducted towards this matter to treat the heavy metals, among which the solidification/stabilization (S/S) is known as one of the effective methods through its low cost implementation and minimum energy consumption. Nevertheless, one of the main issues of this method is that the heavy metal is stayed inside the matrices, not destroyed nor adsorbed, which may cause serious problems for the environment once the matrices would be crashed. To address this problem, the incorporation of some agricultural wastes like rice husk, pineapple leaves, pine leaves, durian shell, coir pith, sugarcane bagasse was needed as heavy metals adsorbents. Different parameters like temperature, particle sizes, contact time, pH and others have shown different efficiencies for the heavy metal adsorption.In the other hand, some mechanical characteristics like the density and the compressive strength have shown different efficiencies towards the S/S method. Heavy metals adsorption by agricultural wastes.Different heavy metals could be discharged to the environment through various sources such as textile, plastics, mining, electroplating, metallurgical processing, batteries, tanneries, fertilizers, paper industries, pesticides, and refining ores (2). Some of these heavy metals are very dangerous for the health and the environment. They may include arsenic (As), cadmium (Cd), chromium (Cr), mercury (Hg), lead (Pb), thallium (Tl) and others (8). In order to avoid their toxicity, tremendous researches have been developed for the removal of heavy metals using low cost methods, among that the agricultural wastes incorporation has been highlighted in this part. The landfilling of agricultural wastes may pollute the groundwater by infiltration and the environment through the greenhouse gas (GHG) emission in the atmosphere. As an alternative solution, some of these agricultural wastes like rice husk (4), pine leaves (5), durian shell (6), coir pith (7), oil palm shell (8) and watermelon shell (3) have shown an effective adsorption capability

This paper presents of Polymer Matrix Composite (PMC) as feedstock used in Fused Deposition Modelling (FDM) machine. This study discussed on the development of a new PMC material by the injection molding machine. The material consist of copper powder filled in an acrylonitrile butadiene styrene (ABS), binder and surfactant material. The effect of metal filled in ABS and binder content was investigated experimentally by the Melt Flow Index (MFI) machine. Based on the result obtained, an increment of copper filled in ABS by volume percentage (vol. %) effected on melt flow index results. With highly filled copper in PMC composites increase the melt flow index results. It was concluded that, the propensity of the melt flow allow an internal force in PMC material through the injection molding and FDM machine.

Ozone (O3) and nitrogen oxides (NOx) are closely related in the atmosphere. In ambient air, these pollutants always fluctuated depending on their emission sources and meteorological influences. The paper is aims to gain insight understanding of the monthly temporal variation of O3 and NOx concentrations to enable proper control strategies against these pollutants. One-year monitoring records from 1st January to 31st December 2009 of O3 and NOx at Pasir Gudang, were obtained from Department of Environmental Malaysia. Temporal analysis of O3 and NOx concentration fluctuation during annual and monthly were assessed using time series and scatter plots. The annual variations of O3 concentrations were negatively correlated with annual variation of NO and NO2 concentrations. Results suggest that NO concentration are higher than O3 and NO2 especially in May 2009. However, zero exceedences were recorded in the studied period for all pollutants against the Malaysia Ambient Air Quality Guidelines.

Greywater (GW) is identified as waste disposal from home activites that is discharging from laundry, bath and wash-basin. GW useful in irrigation of a garden and aids to reduce cost as well as maintain the environmental prosperity. This paper discussed the effectiveness of Botryococcus sp. to clean GW in phycoremediation treatment. This process involves as growing the Botryococcus sp. in the GW which is contributing to utilize supplements in GW for its grow. The results indicated that Botryococcus sp. is effective to reduce COD (88%), BOD (82%), TIC (76%), TC (58%), TN (52%), TOC (39%), Phosphate (37.5%) and pH (7%) for 100% concentration of GW. Meanwhile, for the 50% of GW concentration Botryococcus sp. capable to remove such as COD (83%), TIC (82%), BOD (68%), TN (67%), Phosphate (36.8%), TC (34%), TOC (31%) and pH (1.2%). Then, the study concludes that Botryococcus sp. can grow effectively in GW and be able to reduce the rate of nutrient in GW.

This paper presents the melt flow index (MFI) of acrylonitrile butadiene styrene (ABS) and recycle ABS filament wire for Fused Deposition Modeling (FDM) machine. In this study, the effect of MFI on recycle ABS material was investigated experimentally based on the melting temperature, density, screw speed and material properties. The MFI result on ABS recycle in wire filament was investigated using Melt Indexer Machine (MIM). Based on the result obtained, it was found that, ABS recycle was increase the density and MFI results. It can be observed that, the higher temperature was melt the recycle ABS material through the MIM and extruder machine.

Titanium is a lightweight metal with an outstanding combination of properties which make it the material of choice for many different applications. This paper investigates the structure, surface characteristics and electrical properties of the Titanium Dioxide (TiO2) thin film, deposited by chemical vapor deposition (CVD). The deposition temperature was 1000°C with 3 different positions of the glass substrates. The surface morphologies were examined using a field emission scanning electron microscope (FESEM) and an atomic force microscopy (AFM). In order to investigate the structural properties, the TiO2thickness was measured using a surface profiler. The optical properties of TiO2were measured using an ultraviolet visible spectroscopy (UV-Vis). The surface morphology was found to be sensitive to the deposition parameters and the growth TiO2is more uniform when the position of substrate is closed to the starting material.

value. Abstract. The aim of this paper is to investigate the effects of voltage flow (V) in the alkaline electrolyser system and the pH value (pH) of the electrolyte used in the electrolyser. The output measurement of both investigated factors in in the flow rate of the hydrogen gas produced by the system per minute (ml/min). The voltage flow was altered in the system by altering the voltage supply from the workbench power supply ranging from 11V to 14V. The pH value of the electrolyte solution in the electrolyser was altered by the addition of Potassium Hydroxide (KOH) in the distilled water. The pH value samples of the tested solution ranging from 13.0 to 14.0 pH value due to the limitation of the electrolyser used in this experiment. The results found that, the hydrogen gas produced per minute increases with voltage flow in the system. The flow rate of the hydrogen gas produced however only increases when the solution's pH value reaches at 14 pH level and unreactive below the value.

ZnO nanorods (NRs) arrays were synthesized by chemical solution deposition (CSD) method on commercial glass substrate with ZnO thin film act as seed layer prepared by sol-gel spin coating. The effect of annealing temperature of 150°C, 250°C and 500°C, respectively, on the structural growth was investigated. The observation reveals the structural improvement as the annealing temperature increased. The influence of gadolinium doping to ZnO NRs arrays was explored upon the structural and optical features. The FESEM imaging along with XRD, AFM and UV-Vis analysis were conducted to dissect the information gained by performing a study case on various gadolinium doping content in the range of 1 at. % to 4 at. %. Based on the results, the correlation between the doping content were drawn in details in this paper.

Understanding the interference of multi-bead parameters on surface smoothness is essential for accuracy of the formed parts made by welding rapid forming. This paper presents an investigation on surface smoothness of multi-bead aluminium alloys. Deposition path planning and overlap ratio is manipulated in order to improve surface smoothness. Observation on bead cross section indicates that deposition path planning has remarkable effect on the surface smoothness. Multi-bead that developed using continuous path planning has surface smoothness of 0.46 mm – 1.34 mm and most bead present wavy type surfaces. The surface smoothness is improved by increasing the overlap ratio. Meanwhile, skip path planning produced good surface smoothness of 0.11 mm – 0.28 mm. An improved surface smoothness featuring flat surface type is obtained with this path planning.

This paper reports the results on cracking propagation and pattern of reinforced concrete (RC) beam conducted using irregular-shaped Polyethylene Terephthalate (IPET) as a fibre. Three volume fraction of IPET fibre is used namely, 0.5%, 1% and 1.5%. All RC beam specimens are tested under four point loading under flexural capacity behaviour. Prior to structural test, the materials properties which include the compressive and tensile strength test and modulus of elasticity test were determined. The results than are compared with control RC beam. It is found that the RC beam with IPET fibre does not significantly change the behaviour of failure mode, cracking propagation and pattern compared to control RC beam.

Groundwater quality is generally affected by the soil type and being polluted naturally due to the soil properties itself. This paper aims to examine the effectiveness of reducing the contamination of groundwater by a simple treatment using duo soil aquifer treatment (SAT) and therapy-electrolysis processes. The SAT was applied using physical recharge well system (REWES) in deep clay medium. The filtration in the well was also properly designed to purify the abstraction and treat discharges. Other contaminations such as fluoride, nitrate, chloride and turbidity in the groundwater were treated by therapy-electrolysis techniques. This treatment method reduces more than 64% of contaminations contain without affecting its mineralogy. Therefore, these duo treatments have the best combination of methods to reduce the unneeded contaminations without affecting the groundwater purity. A groundwater eco-distribution system is useful to be implemented in terms of economic process and is ecological friendly for water distribution facilities.

This paper presents physical characteristic of Rhodococcus zopfii through the use of Environment Scanning Electron Microscopy. This bacterium is very significant in enhancing degradation of polycyclic aromatic hydrocarbons (PAHs) in the presence of natural biofilm in waste water treatment system. Rhodococcus Zopfii was isolated from municipal sludge at Universiti Teknologi MARA. The average size of Rhodococcus Zopfii was measured in the range of 1.1–2.85 μm lengths and 0.55-0.80 μm diameters. The colour of this bacterium was slightly pink on agar plate and it had rod shaped. Experimental results obtained from confocal laser scanning microscopy showed that this bacterium can easily attach on the surface of biofilm. The experimental results provide a scientific knowledge of physical characteristic of Rhodococcus Zopfii isolated from municipal sludge to grow on natural biofilm in wastewater treatment system.

This paper reports the influence of light exposure (photodynamic) and magnetic field application on viability activation of anaerobic photosynthetic bacteria (rhodobacter sphaeroides). For photosynthetic process, the rhodobacter sphaeroides have bacteriochlorophyll and carotenoid as major and accessory pigments, respectively. A customized equipment was developed for investigating the effect of light and magnetic field applications on the growth of the bacterial colonies. It was consisted of three main parts, namely a sample holder, an array of light emitting diode (LED) as light source and Helmholtz coils as magnetic field source. The systems of this equipment were controlled by a microntroller of AVR ATMega-8535. Prior to the application in vitro, all LEDs were calibrated, both their intensity and wavelength. After the treatments, all bacteria substances were grown in photosynthetic media (PMS) for 48 hours followed by calculating the number bacterial colonies growth using a total plate count (TPC) method and Quebec colony counter. It was found that the growths of bacterial colonies were influenced by both light intensity and wavelength of LED array. At the same intensities, the wavelength of 430 nm showed highest effect on the growth of bacterial colonies. In addition, upon application of the optimum light combined with magnetic field, the highest growth of bacterial colonies was achieved more than 110% when the optimized light source of energy dose was 204 J/cm2 and magnetic field was 1.8 mT.

This paper discusses the experimental results on the mechanical properties of hybrid fibre reinforced composite concrete (HyFRCC) containing different proportions of steel fibre (SF) and polypropylene fibre (PPF). The mechanical properties include compressive strength, tensile strength, and flexural strength. SF is known to enhance the flexural and tensile strengths, and at the same time is able to resist the formation of macro cracking. Meanwhile, PPF contributes to the tensile strain capacity and compressive strength, and also delay the formation of micro cracks. Hooked-end deformed type SF fibre with 60 mm length and fibrillated virgin type PPF fibre with 19 mm length are used in this study. Meanwhile, the concrete strength is maintained for grade C30. The percentage proportion of SF-PPF fibres are varied in the range of 100-0%, 75-25%, 50-50%, 25-75% and 0-100% of which the total fibre volume fraction (Vf) is fixed at 0.5%. The experimental results reveal that the percentage proportion of SF-PPF fibres with 75-25% produced the maximum performance of flexural strength, tensile strength and flexural toughness. Meanwhile, the percentage proportion of SF-PPF fibres with 100-0% contributes to the improvement of the compressive strength compared to that of plain concrete.

We have reviewed humidity sensors based on the Zinc oxide (ZnO) humidity sensor. There are only a few papers reviewing on the ZnO humidity sensor. The characteristics, structures, advantages, and fabrication methods of ZnO have been studied to understand the suitability of the ZnO to be applied at different kind of condition such as for extreme environment, low level humidity detection, and very high humidity level circumstances. The electrical and physical properties of ZnO humidity sensors such as sensitivity, response time, stability, uniformity, and crystallinity have also been discussed in this review. ZnO nanostructures have been widely used for humidity sensors because of its’ good stability, high sensitivity for humidity-sensing, low cost, and has a wide band gap. Sol-gel preparation method is commonly used to for ZnO humidity sensor fabrication since it can produce a film with high uniformity, simple process and low cost. Keywords: Humidity Sensor, Metal Oxide, Semiconducting Type, Ceramic Type, Humidity-Sensing, Band Gap, Sol-Gel Preparation Method.

This study aims to measure the concentration of heavy metals of concern Lead (Pb), Copper (Cu), Chromium (Cr), Cadmium (Cd) and Nickel (Ni) at three university campus buildings which was situated adjacent to an industrial district. Heavy metals particulates were sampled from the PM10 sampling device (Met One Instrument) in 24 hours sampling between lecture and holiday periods. Determination of heavy metals concentrations were conducted using Inductively Coupled Plasma – Mass Spectrometry (ICP-MS) after the filter papers were digested with mixture of nitric acid (HNO3) and sulphuric acid (H2SO4). These heavy metal concentrations were compared to the Standard Concentration on Air such as World Health Organization Health (WHO), Ambient Air Quality Criteria Act 1994 (AAQC), National Environment Protection Council (NEPS) and also Texas Commission on Environmental Quality (TCEQ). The comparison with Standard Concentration of Air shows that Cd and Cu have low concentrations 0.0033±0.0018 μg/m3 and 0.0894±0.0614 μg/m3 while Cr and Ni have high concentrations of 0.1882±0.0535 μg/m3 and 0.1278±0.0323 μg/m3 respectively. The Pb gives irregular result and high standard deviation of 2.0410±3.4999 μg/m3. This finding produces significant contribution to some knowledge of the level of heavy metals in the study area. It identifies research needs and suggests potential approaches to addressing outstanding problems.

Uniform Titanium dioxide (TiO2) thin film is essential for application in high performance solar cells. A low cost approach using TiO2nanopowder extracted from tin mining waste to deposit TiO2thin films is demonstrated in this paper. Furthermore, the influence of different solvents (ethanol, acetone, isopropanol and ethylene glycol) on the formation of uniform TiO2thin films in sol-gel technique is studied. The films were characterized by an atomic force microscope (AFM), ultra violet – visible spectrometer (UV-Vis) and a current-voltage (I-V) measurement system. The correlations of the structural, optical and electrical behavior to the type of solvent used were discussed in details.

In recent years there has been renewed interest in zinc oxide semiconductor, mainly triggered by its prospects in optoelectronic applications. Doping ZnO with various elements has been a popular technique to gain the extrinsic properties for device applications. In this work we have studied the effect of Gadolinium (Gd) concentration on properties of sol–gel derived Gd doped ZnO films. The Gd concentration varying from 1 to 8 atomic percent (at.%). The structural, morphological and optical analyses were monitored by (XRD, Bruker D8 Advance), atomic force microscope (AFM, Tenko XE-100) and ultra violet-visible spectrophotometer (UV-Vis, Shimadzu UV 1800), respectively. Observations from the XRD results showed that all films exhibit the hexagonal wurtzite crystal structure and higher peak intensity observed at (002) peak. Based on XRD analysis, we also found that Gd concentration has a significant effect on the crystallite size and strain of the films. Moreover, the AFM analysis revealed that the surface become more uniform and denser as the Gd concentration increased. In addition, the optical transmittance spectra indicate that all films were highly transparent (>90%) in the visible range which slightly improved with increasing Gd concentration. The detail explanation on the mechanism will be discussed in detail in this paper.

This paper investigates the parameter optimization of a preheating method on stainless steel SUS304 prior to aluminium-stainless steel dissimilar welding. The welding method used was metal inert gas (MIG) with butt joint type weld. The Taguchi L9 orthogonal array was used to investigate the optimum parameter, while the mechanical strength was investigated using tensile test. Optimum levels of the process parameters were analyzed using the Taguchi parametric design approach. Parameter analysis of the tensile test results indicate that the preheated specimen with 90 °C have the maximum ultimate tensile strength of 111.27 MPa. This value is in close proximity to the calculated value of 109.02 MPa with 2% error. Through analysis of variance (ANOVA), the welding current was the dominant contributing factor with 40%. It can be concluded that the highest tensile value (111.27 MPa) for AA6061-SS304 dissimilar welding was obtained using 90 °C preheating, voltage of 17.5 V and current of 110 A of current.

This paper presents the results of using ground dune sand (GDS) and ground granulated blast furnace slag (slag) as high volume cement replacement materials. In this study, plain and four blended mixtures were fabricated and cured under normal and autoclave conditions. For the blended mixtures, 40% GDS by weight of the total binder materials and different percentages of slag (15%, 30% and 45%) were incorporated as partial cement replacement materials. The effect of curing conditions (normal and autoclave) on the compressive strength of prepared mixtures was studied. The results showed that, for the autoclave cured mixture, up to 85% of cement can be replaced by GDS and slag without significant drop in the compressive strength. Microstructure analyses using scanning electron microscope (SEM) and X-ray diffraction analysis (XRD) were carried out to examine the microscale changes of the hydrated mixtures. The SEM revealed the formation of thin plate-like calcium silicate hydrate and compacted microstructure of autoclave cured mixture. XRD showed the elimination of calcium hydroxide and existence of residual crystalline silica of all blended mixtures.

This paper will focus on experimental investigation to observe the effects of different densities and additives on the thermal properties of foamed concrete by means of Hot Disk Thermal Constant Analyzer, so as to obtain a few fundamental thermal properties for prediction of its fire resistance performance. For this study, samples of three different densities of 700kg/m3, 1000kg/m3 and 1400kg/m3 and various additives were investigated to study the effects of densities and additives on the thermal properties of foamed concrete. The additives used in this research were pulverized fuel ash (PFA), silica fume, palm oil fuel ash (POFA), wood ash, polypropylene fibre, steel fibre and coir fibre. It should be pointed out that the lowest density of foamed concrete (700kg/m3) has provided best thermal insulation properties due to large amount of pores and high percentage of air entrapped because air is poorest conductor of heat than solid and liquid. Also, foamed concrete with coir fibre achieved lowest thermal conductivity because it possess high heat resistance due to its large percentage of hemicellulose and lignin and exhibited high heat capacity as well due to the formation of uniform pores and voids in foamed concrete.

In the paper we construct a mathematical model of turbulent flow, combustion and heat transfer in an axisymmetric chamber with an axial zone of a compacted particulate material. The averaged equations written using the model of interacting and interpenetrating continua contain diffusion equations of individual components, the energy equation for the gas and the porous structure, the motion equation for a mixture of gaseous components, as well as the equation of the turbulence model. This system is closed by the equations of continuity and condition of the mixture. In the flow, an irreversible chemical reaction of stoichiometric mixture of methane and oxygen proceeds. Numerical study of porosity influencing the nature of turbulent combustion is conducted.

In this paper, a novel perylene diimide derivative 1, 7-bis (N, N-bis (4-phenyl) aniline) perylene diimide (PDI-TPA) was synthesized and characterized by IR spectroscopy, 1H NMR and elemental analysis. Besides, solubility and photoelectric properties of PDI-TPA were studied. Results were shown that PDI-TPA exhibited an excellent solubility in common solvents. The absorption bands spanned a wide range of the visible spectra and optical band gap was 1.68 eV. In addition, PDI-TAP exhibited an ambipolar behavior, the highest occupied molecular orbital (HOMO) energy level and the lowest unoccupied molecular orbital (LUMO) energy level were-5.64 eV and-3.94 eV, respectively.

This paper empirically investigates the variations of embodied energy (EE) and carbon (EC) intensities of materials and identifies their parameter variations in hybrid life cycle assessment (LCA). These parameters include energy tariff, primary energy factor, disaggregation constant, emission factor, and price fluctuation. Hybrid LCA has been conducted to expand the system boundary by filling the gaps in traditional LCA data inventories. The Malaysian Input-Output (I-O) tables are used to derive indirect energy and carbon intensities which are then combined to take advantages of detailed process LCA. The results revealed that maximum increase in energy tariffs and material price fluctuations were the key parameters and issues leading to higher variations in EE and EC intensity values. Other parameters – such as maximum increase in primary energy factor, emission factor and excluding disaggregation constant – have a slight impact upon EE and EC intensity variations. Building materials with high indirect energy in the upstream boundary of materials production have high influence on hybrid LCA variation. Therefore, any decision relating to these materials should be considered carefully.

In this paper, the effect of inert gas plasma to the morphology of 0.29μm thick 3C-SiC/Si is studied. Helium was used for the plasma treatment and its effect as the etchant gas to the polished side of 3C-SiC/Si surface was determined. The changes of the surface morphology were monitored using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). From the results obtained, it has shown that the morphology of surface properties of 3C-SiC was modified by differences in helium plasma time of exposure and the degree of roughness of the surface changes. The results show by the SEM and AFM shown that plasma treatment had been successfully implemented for the 0.29μm thick 3C-SiC/Si.

Recent studies have been carried out to utilize waste glass in construction as partial cement replacement. This paper investigates the formation of Calcium Silicate Hydrate (C-S-H) and strength characteristics of mortar in which cement is partially replaced with glass powder by replacement level of 10%, 20% and 30%. Mortar cubes containing varying particle sizes in the ranges of 150-75μm, 63-38 μm and lower than 38 μm and in a water to cement ratio of 0.45 and 0.40 have been prepared. Replacement by 10% cement with glass powder reveals high compressive strength and produces more C-S-H at 28 days than other levels of replacement.

This paper investigates the potential of utilizing the undeveloped natural gas fields in Malaysia with high carbon dioxide (CO2) content ranging from 28 to 87%. For this experiment, various CO2 proportions by volume were added to pure natural gas as a way of simulating raw natural gas compositions in these fields. The experimental tests were carried out using a 4-stroke single cylinder spark ignition (SI) direct injection (DI) compressed natural gas (CNG) engine. The tests were carried out at 180°CA BTDC injection timing and 3000 rpm, to establish the effects on the engine performance. The findings revealed that the brake torque decreased by 9% with 20% CO2 proportion in the mixture due to the decrease in the heating value of the mixture. At the same proportion of CO2, the brake specific fuel consumption decreased by about 8.5% and the brake thermal efficiency increased by 9.2%. There was a reduction in the unburnt hydrocarbons (THC) and carbon monoxide (CO) emissions by 15% and 89% respectively, but the NOx emissions increased by 78%. The utilization of natural gas with 20% CO2 content as fuel in DI-CNG engine was found to be viable with insignificant drop in engine performance and with reductions in exhaust emissions.

Due to the fact that material is being removed from the bulk material, all machining operations have some impact on the resulting surface integrity of the machined components. This paper presents an investigation on surface microhardness on machining of TiC reinforced aluminium LM6 alloy composite using uncoated carbide tool under dry cutting condition. The experiments that were carried out consisted of different cutting parameters based on combination of cutting speed, feed and depth of cut as the parameters of cutting process. The microhardness of machined surface at a range of cutting speed, feed and depth of cut were measured. The results show that the microhardness was generally found to be higher near the machined surface layer than the hardness of the matrix in the bulk material during machining for all cutting condition. Microhardness increases beyond the bulk hardness of material occurred 50 μm below machined surface, and then microhardness starts to decrease and reaches the bulk hardness. The microhardness values increases with increased the feed and depth of cut. The highest microhardness recorded was 68 HV0.5when machining at a lower cutting speed of 100 m min-1, feed of 0.2 mm rev-1and depth of cut of 1.0 mm.

This paper focuses on the monitoring of indoor air quality parameters, namely: indoor temperature, humidity, velocity, particulate matter, carbon monoxide and carbon dioxide in day care centres. This study selected 15 day care centres located in Kuala Lumpur, Malaysia. These day care centres were categorized as follows: (1) day care centers near an industrial area, (2) day care centers near a main road, and (3) day care centers in a residential area. The obtained data showed that the values for the indoor air quality parameters in all day care centres were still well below the recommended value according to the Department of Safety and Health, Malaysia. The day care centers near an industrial area had the highest value of carbon monoxide, and carbon dioxide as compared to the day care centers near a main road and the day care centers in a residential area. The average concentrations of carbon monoxide, and carbon dioxide in the day care centers near an industrial area were 3.67 ppm and 801.56 ppm respectively. Meanwhile, the carbon monoxide, and carbon dioxide in the day care centers near a main road area and the day care centers in a residential area were 3.13 ppm, 768.22 ppm, 2.92 ppm and 733.70 ppm, respectively.

This paper presents the crushing behaviour of empty and foam-filled conical tubes under axial dynamic loading. A nonlinear finite element (FE) model was developed and validated against experiments. The validated model was subsequently used to assess the beneficial of foam filling with regards to the variation in filler densities and tube materials. The results obtained were further analyzed and compared with straight tubes. We aim to evaluate the critical effective point for different density of fillers in foam-filled tubes based on specific energy absorption (SEA) value. The SEA value was highest for foam-filled conical aluminium tube with aluminium foam filler, followed by straight aluminium tube, straight carbon steel tube and conical carbon steel tube. Moreover, the initial peak force was found lower in aluminium tubes than carbon steel tubes and lower in conical tubes than that in straight tubes. The combination of conical aluminium tube and aluminium foam filler successfully convey the beneficial of foam filling and thus signify that proper combination and selection of tube and filler is vital in assessing the effectiveness of foam-filled tubes.

In this paper, the stiffness mechanical property of natural fiber reinforced thermoplastic composites is analyzed using composite micromechanical model. Kenaf natural fiber is selected as the reinforcement material in the composites construction while three types of commonly used automotive grade thermoplastic matrices, namely polypropylene, acrylonitrile butadiene styrene and polyamide 6 were selected to be reinforced with kenaf fibers. Their stiffness property was later analyzed using Halpin-Tsai micromechanical model at varying fiber content and fiber aspect ratio conditions. In all cases, theoretical results show that the kenaf reinforced thermoplastic composites stiffness increased linearly as the fiber contents were increased. Apart from that, results also show that the stiffness property also increases as the fiber aspect ratio was increased. Higher final composites stiffness property was also observed as stiffness matrix material is utilized in the composites formulation. The prediction results also provided valuable and quick insight as well as cost effective alternative to composite designers in assessing the stiffness performance of natural fiber composites especially those which are reinforced with thermoplastic matrices compared to conventional experimental technique for automotive product development purposes in addition to identifying the optimal parameter to be put into focus in their composites design to achieve the intended design performance specifications.

At this paper attempts have been made to determine the effects of internal pressure on the reinforced composite pressure vessel. Finite element analysis (FEA) along with the Tsai-Wu failure criterion was utilized to predict the failure pressure of the vessel and the optimum fiber angle orientation. Six layers of E-glass/Epoxy and Graphite/Epoxyfibers have been selected to reinforce the aluminium vessel. Fibers were oriented with six different winding angles of 300, 450, 550, 600, 750 and 900 at asymmetric fiber orientation. The commercial code ABAQUS CAE was employed to simulate the model and analyse the structure. Results were revealed that Graphite/Epoxy has higher strength in comparison with E-glass/Epoxy fiber. Also it was observed that for both composite materials 550fiber angle is the optimum winding angle. Results were compared to the experimental ones and there was a good agreement between them.