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The aim of this paper was to investigate the effects of cross-linked reaction on physicochemical properties of chitosan film by using genipin as cross-linker agent. Series of chitosan film samples with different amount concentration of genipin loaded (0-3 wt %) were prepared and characterized. The physicochemical properties of films were evaluated by Fourier Transform Infra-red (FTIR), UV-vis spectroscopy, Oxygen Transmission Rate (OTR), Scanning Electron Microscopy (SEM), water vapour and tensile test. The cross-linking reaction had affected on colour changing of chitosan film samples from light yellow to dark blue in line with the increasing of genipin concentration. Thus, UV-vis spectroscopy on the cross-linked samples showed the absorbance value at 600 nm wavelength due to genipin content. FTIR observation on cross-linked film samples showed no characteristic of –OCH3 peak from genipin at 1444 cm-1 which resulted by new covalent bonding occurred between chitosan and genipin. Cross-linking also had increased the oxygen barrier and reduced the water vapor rate through the film. Chitosan film sample with addition of 1 wt% genipin achieved the highest tensile stress average at 49.46 MPa compared to other samples while percent of elongation at break reduced with the increasing of genipin concentration loaded

Galactomannan is a biopolymer polysaccharides mostly obtained from Leguminosae plant have shown an interesting capability as drug carrier. In this study, galactomannan from the seeds ofLeucaenaleucocephalaknown locally as ‘petai belalang’ was obtained by water extraction. The galactomannan was characterized structurally by nuclear magnetic resonance (NMR) and fourier transform infrared spectroscopy (FTIR). Highly molecular weight of galactomannan, > 2.56 x 106Da, was successfully extracted from the plant. Total carbohydrate content of this polysaccharides is 74.84% and composition of galactose and mannose have been confirm by high performance liquid chromatography (HPLC) which is 36.67% and 38.17% respectively. M/G ratio was determined as 1:1. Hence, galactomannan has been successfully extracted from the seeds ofLeucaenaleucocephala.

This research aims to study the effect of activated carbon particles in adsorption of the methylene blue as a replacement of wastewater treatment when coated on a high density polyethylene (HDPE) substrate (e.g. flat sheet and cosmo ball substrates). Prior to coating, the activated carbon has been cleaned using tab water to remove ashes which blocks the activated carbon pores. Coating was done by applying epoxy material using brushing technique, and then sprayed the activated carbon on epoxy either manually or using spray machine. The thickness and morphological of the coatings were characterized using Scanning Electron Microscopy (SEM). Analyses conducted have confirmed that granuler activated carbon coating layers ranged between 100 to 500 μm have been successfully deposited on different shapes of HDPE substrates. The coatings deposited on HDPE substrate produced high surface roughness of around 7 μm. The ability of the coated samples in removing the colour of methylene blue is believed due to the high porosity of the activated carbon(AC). The surface area has been increased dramatically if compared with uncoated substrate since the BET of activated carbon is 426 m2/g .

In this work, the prediction of the overpressure resulting from a vapor cloud explosion (VCE) will be conducted from external area of a chemical process plant. Based on Feyzin Refinery disaster, this study will analyzed and focused on the spillage from a delayed ignition causing a VCE from the T61-443 sphere tank. TNT Mass Method and Baker-Strehlow models are used to estimate the overpressure of the explosion. The results are presented in the form of table and figures to compare the two methods and justify the overpressure predicted.

Treated palm oil fuel ash waste was used as substitution materials for silica in in order to fabricate mullite ceramic. Alumina powder was added into the treated palm oil fuel ash in order to supply a deficient alumina component according to the alumina/silica molar ratio of mullite. Mullite phase was successfully achieved upon sintering at temperature above 1220 oC besides other minor impurities, such as perovskite, Al2O3 and SiO2. The surface of samples becomes smoother as the sintering temperature increased to 1270 oC whilst forming closed pore morphology. Besides that, the hardness of the samples increased as an increasing in the sintering which is attributed not only to the full densification of pores on the surface, but also due to the presence of mullite phase.

Development of rare earth doped silica fibre fabrication using MCVD furnace chelate vapor phase delivery is presented. In this study, erbium and aluminium is used as the dopant with precursor erbium (III) tris (2,2,6,6-tetramethyl-3,5-heptanedionate) and aluminium chloride respectively. The preform was designed for 10 layers of SiO2-P2O3doped silica (clad structure) and 5 layers of SiO2-Al2O3-Er2O3(core structure). Preform is analysed for the properties of layer structure i.e. refractive index profile using preform index profiler and EPMA (SEM-EDX) for dopant distribution. Results show good longitudinal uniformity despite condensation of metal organic precursor during the fabrication process. Maximum incorporation of Er2O3is about 0.1 mole % with 1.5 mole% of Al2O3in the core.

Nanoemulsions are a class of nanomaterials which play an increasingly important role in commercial and environmental aspects. Water-in-diesel (W/D) nanoemulsion is considered one of the environmental friendly alternative fuels for reducing the emission pollution of internal combustion engine such as diesel engines. In this context, a study has been made to evaluate the combustion characteristics of W/D nanoemulsion fuel. A wide range of surfactant concentration (0.25% to 0.40% v/v) with varying amount of water percentage (0.5% to 0.8% v/v) was used in the preparation of W/D nanoemulsion fuel. The high energy emulsification method was applied to prepare W/D nanoemulsions. The combustion characteristics of W/D nanoemulsions are presented in terms of different formulating compositions. An engine test bed was used to combust the W/D nanoemulsions for measuring the exhaust emission concentrations such as CO, CO2and NH3. A reduction in the concentrations of exhaust gas emissions was notified.

Growing carbon nanotubes (CNT) on the surface of high performance carbon fibers (CF) offers a means to tailor the mechanical properties of the fiber-matrix interface of a composite. In the context of this work, a floating catalyst chemical vapor deposition (CVD) unit was utilized to grow CNT onto the surface of CF. The surface and mechanical properties of the resultant fibers, CNT density and alignment morphology were explained to depend on the CNT growth temperature, growth time, and atmospheric conditions within the CVD chamber. Single fiber/Epoxy composite coupons were fabricated by using both neat and CNT-coated CF to conduct single fiber fragmentation test (SFFT). It was observed that the coating of CNT onto CF surface improves the IFSS between CF and matrix when compared with neat-CF. Particularly, CF treatment condition for CNT-coating with 700 °C reaction temperature and 30 minutes reaction time has shown a considerable increase in IFSS approximately of 45% over that of the untreated fiber from which it was processed. The fiber-matrix adhesion was analyzed by using SEM on cryogenically fractured surface of both types of composites. The proper justification of fiber-matrix adhesion featured by composite interfacial properties was explained through IFSS.

Galactomannan nanoparticles possess attractive properties such as biodegradable and biocompatible; significant in biomedical applications. Galactomannan (GA) isolated from the mature seed of a local plant, petai belalang known scientifically as Leucaena leucocephala were modified to acrylated galactomannan (AcGA) which acted as a precursor molecule for the preparation of crosslinked galactomannan nanoparticles (CL-GA). AcGA was synthesized using acryloyl chloride (AC) as a chemical modifier through esterification process. Trimethylolpropane triacrylate (TMPTA) was used as the crosslinker for the preparation of CL-GA. Successful conjugation of GA with acrylates was verified by 1H NMR and FTIR spectroscopies. Thermal properties of pure galactomannan, AcGA and CL-GA were measured using DSC to complement spectroscopic results. TEM images revealed the particle size of AcGA to be in the range of 30-100 nm; and increased to 200-850 nm range after the crosslinking process. Efficiency of CL-GA to trap crystal violet dye as a model drug was followed by UV Vis Spectroscopy. Results showed that CL-GA is capable of trapping crystal violet dye and has the potential to be used as a drug carrier.

User knowledge has become a performance indicator that determines the success of a business. It provides a valuable source of information for product developer to develop the specification and characteristics of a new product. Various methods have been studied to extract and integrate the user knowledge during the early stage of a design process. This paper focuses the relation between the success of a product and the product specification. Interviews with product designers were conducted. The results of this study provide a foundation for product developers to specify the product characteristics. The strategies, information and knowledge for a structured approach to product characteristics can then be developed.

The effects of calcium carbonate (CaCO3) addition on the physical properties of ZnO-based crystal glaze batches were investigated. Samples were fired at different gloss firing temperatures ranging from 1180-1220°C with 3 hours soaking at 1060°C crystallization temperature. X-ray diffraction (XRD) analysis identifiedthe crystal phase occurred as willemite (Zn2SiO4) and the scanning electron microscope (SEM) analysis indicated that willemite crystals are in the acicular needle like shape that formed spherulite. The intensities of willemite peaks decreased with CaCO3 addition and completely vanished at 5.0 wt% CaCO3. Varied formation of spherulites developed of the surface of crystal glaze as the flows of the glaze stretched further as the amount of CaCO3 increased.

Nowadays, consumers have become more selective in choosing products not only deciding based on its functionality and its value but also on its aesthetic and emotional value. Aesthetic and emotional values have thus become important aspects in the success of a product in a competitive market. Consequently, recognizing the primary parameters used to generate combinative product shape which has the ability to evoke a particular emotion should be given strong consideration. This paper describes the application of robust design approach which allows the designer to determine the optimal design parameters to obtain form impression evoked by a product shape feature. A Taguchi’s orthogonal array method is applied to design the experiment and is analyzed to obtain the optimal parameters for each factor. ANOVA is then employed to identify the most significant factors. A Taguchi’s L18orthogonal array was adopted for an experiment on the design of an office chair. The case study contains six three-level factors, and 18 different combinative design samples created from shape parameters. The results of the experiment shows that it is possible to create a design support system that can facilitates the designer in the creative process by suggesting shape parameters relating to a specific form impression.

Undoped and Mn doped ZnO films with different percentage of doping concentration (2%, 4%, 6% and 8%) were synthesized by sol gel method with an annealing temperature of 400°C. As to investigate the physical properties and microstructures, the samples are characterized using FESEM. The surface morphology images on the films showed many spherical shaped nanoparticles and separate uniformly. Meanwhile, the optical properties were characterized using UV-Vis where the transmittance and band gap value were affected by certain amount of Mn concentration. These films achieve tunable band gap characteristics by means of changing the dopant concentration. At lower concentration, 2% and 4% of Mn, the band gap is reducing compare to undoped ZnO. At higher doping for 6% and 8% of Mn, the bang gap suddenly increased.

Mn doped ZnO films with different doping concentration were synthesized by sol gel method using the spin coating technique. Zn1-xMnxO thin films are prepared using 2-methoxyethanol solution of zinc acetate dehydrate and manganese acetate tetrahydrate. The quantity of Mn in the sol was synthesized with undoped ZnO, 2%, 4%, 6% and 8 % of Mn doped ZnO with an annealing temperature of 500°C. The FESEM images showed many spherical shaped nanoparticles on the cross-sectional of the films. The optical properties were characterized using UV-Vis where the transmittance and band gap value were affected by certain amount of Mn concentration. These films achieve tunable band gap characteristics by means of changing the dopant concentration. It shows an initial decrease of band gap for small concentrations of Mn, followed by an increase at higher Mn doping concentrations.

We report the fabrication and characterization of an ultraviolet photoconductive sensing by using Al-doped ZnO films. Undoped ZnO, 1 at.% and 2 at% of Al were prepared on quartz glass by sol gel method with annealing temperature of 500°C for 1 hour. The presence of spherical shaped nanoparticles were detected for undoped ZnO by using FESEM. The absorption edge shifted to a lower wavelength by doping with Al and excitonic peak can be observed. The band gap values increased by adding Al. I-V curves reveal an ohmic line and improvement in electrical conductivity when the samples are illuminated by ultraviolet (UV) light with a wavelength of 365 nm. At 1 at.% of Al, the film have a larger increment in photocurrent response when illuminated with UV light compared to undoped ZnO and 2 at.% Al. The thin films have a longer recovery time than response time.

Currently, there is a distinct lack of innovative approaches to designing and building houses in Malaysia that could overcome the harsh climatic conditions to achieve thermal comfort. At the same time, demand for residential air-conditioning units has skyrocketed due to the lifestyle expectations of home buyers, the low prices of the units and the very low national residential electricity tariff. Most existing and new houses are not designed to be air-conditioned properly due to poor building material selections and endemic construction practices. These houses are not sealed and are thermally inefficient. Besides looking back to the indigenous passive solar design strategies, new design paradigms have to be explored and promoted for the benefit of all. One innovative approach that has been well-developed and proven successful is the Cooltek concept which was first used at a private bungalow in Melaka, Malaysia. The overarching principle of this concept is to reverse the role of the building envelope of colder climates from keeping the heat inside the building to keeping the heat out of the building which could provide a more conducive indoor environment for air-conditioning in order to reduce the indoor temperature and the relative humidity with minimal use of electricity. This paper describes the Cooltek concept and a case study in detail and how the concept works.

Achieving thermal comfort in the tropical climate of Malaysia is always a great challenge for any house designer or builder. Although some practical solutions have been developed over centuries through the slow but constant evolution of indigenous houses such the Malay house, the longhouses in Borneo and the Chinese townhouses in Melaka, their integration into contemporary designs have been hampered by various modern constraints. For instance, building the Malay house in urban areas is deemed unsuitable due to the need for wide land lots and their perceptively fragile building materials that do not allay any security worries. The lack of skilled carpenters for building such a house is also a worsening problem. Hence, new and innovative strategies to achieve thermal comfort for contemporary houses are greatly needed to serve the needs and expectations of an urbanized society. One method that has been studied and proved successful is the Smart and Cool Home system which was first used at a private bungalow in Semenyih, Malaysia. The overarching principle of this system is to reverse the role of the building envelope from being a thermal mass into a heat sink which effectively reduces heat gains and allow the occupants inside to easily adapt to a milder indoor environment. This paper describes this house in detail and provides some understanding of the principles involved.

Ceramic products with crystalline structure on its body give an artistic effect. The usage of zinc oxide which acts as a flux material has a beneficial effect in many colored glazes amongst which is crystalline glaze. Samples are fired at different gloss firing temperature of 1200oC to 1250oC for half an hour and hold for five hours at crystal growth temperature. After firing, the morphology of crystalline structure on the ceramic substrate body was identified using visual observation. The result show crystals start to develop at 1230oC of gloss firing temperature. Scanning Electron Microscope (SEM) analysis shows that these crystals are made of acicular needle shape crystals. X-ray Diffraction (XRD) and Energy Dispersive X-ray Spectrometer (EDX) analysis of the phases identified these crystals as willemite, Zn2SiO4 which formed spherulites. The results also show obvious growth and distance distribution between each of spherulites as the gloss firing temperatures increase to 1250oC.