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In this study, the preparation of monolayer array template was performed using 0.2 µm polystyrene (PS) nanospheres monodisperse micro particle deposited onto Indium Tin Oxide (ITO) coated glass substrate. The template was used to arrange the gold (Au) in nanomesh structure thus, enhance its homogeneity for having better sensitivity and repeatability in the plasmonic sensor application. PS nanosphere template was prepared by diluting 0.2 µm PS liquid with ethanol in the ratio of 1:3 and stirred with 400 rpm for 1 hours at 40 °C. Next, the PS solution was spin coated on ITO substrate at different speed variation starting from 200 rpm to 800 rpm in 3 minutes at room temperature. The template structure was then inspected with Field Emission-Scanning Electron Microscopy (FESEM). It was found that, the PS nanosphere template with 600 rpm speed shows the most orderly arrangement of PS array. Subsequently, the PS array template was used as a mask to deposit gold (Au) and performed via direct current (DC) sputtering method. Finally, the Au nanomesh structure was obtained using the lift ‒ off process of PS nanosphere template.

Glass series of quaternary lead-zinc-borosilicate glass was fabricated using melt-quenching method. It was successfully prepared using silicon dioxide (SiO2 99.37 %) as the network former, which was obtains from rice husk ash (RHA). The thickness of the prepared glass samples used during the measurement was 0.3, 0.4 and 0.5 cm. As the percentage of PbO increased from 5% to 40%, the density and molar volume of glass sample increased from 3.719 g/cm3 to 5.010 g/cm3 and 21.44 cm3 to 25.82 cm3, respectively. The significant modification was due to augmentation in bond length and increment in inter-atomic spacing between atoms with the presence of Pb, Zn and B atoms. Nevertheless, the oxygen packing density decreased from 79.29 g-atom/l to 65.84 g-atom/l. The mass attenuation coefficient was found to be increased for 0.3 cm, 0.4 cm and 0.5 cm. The escalating mass attenuation coefficient was due to the increment of PbO percentage mole, which related to the emergent photoelectric absorption of the glass sample. Thus, it also affects the decreasing trend of Half Value Layer (HVL) and the increasing of Effective atomic number (Zeff).

A glass series of erbium doped zinc borosilicate glass system was prepared by using the melt-quenching method. The absorption spectra revealed several bands at visible range which correspond to the following transitions (from the ground state); ⁴F5/2 + ⁴F7/2 + ²H11/2 + ⁴S3/2 + ⁴F9/2 + ⁴I9/2. The density and molar volume obtained increased and decreased respectively as the concentration of erbium oxide varied from 0 mol % to 1.0 mol %. Meanwhile, oxygen packing density (OPD) increased as the concentration of erbium oxide increased up to 3.0 mol % due to the build-up of bridging oxygen. The indirect band gap energy was achieved from 2.56 eV to 2.80 eV and the Urbach energy values lies between 0.15 eV and 0.61 eV.

A functional mini protein can be developed by miniaturising its size. The minimisation technique provides an excellent model system for studying native enzymes, especially in creating an alternative novel biocatalyst. Miniaturised proteins may have enhanced stability, a crucial characteristic for large-scale production and industrial applications. In this study, a huge enzyme molecule, known as diamine oxidase (DAO, comprising 700 amino acids), was selected to undergo the process. By retaining the arrangement of the original functional sites of DAO in the fourth domain, a mini DAO can be designed via homology modelling. After several downsizing processes, a final configuration of 220 amino acids displayed high binding affinity towards histamine, a short-chain substrate that was catalysed by the parental DAO. The configuration also showed enhanced affinity towards a long-chain substrate known as spermidine. The gene for the designed protein was cloned and expressed in pET102/TOPO vector and overexpressed in E. coli BL21 (DE3). The new mini DAO had similar temperature tolerance and versatile substrates specificity characteristics as its parental protein. An active mini-protein with these characteristics is potentially useful for several applications such as detecting biogenic amines in the biological fluids and the environment that may give rise to health issues.

This study was conducted in order to optimise simultaneous saccharification and fermentation (SSF) for biobutanol production from a pretreated oil palm empty fruit bunch (OPEFB) by Clostridium acetobutylicum ATCC 824. Temperature, initial pH, cellulase loading and substrate concentration were screened using one factor at a time (OFAT) and further statistically optimised by central composite design (CCD) using the response surface methodology (RSM) approach. Approximately 2.47 g/L of biobutanol concentration and 0.10 g/g of biobutanol yield were obtained after being screened through OFAT with 29.55% increment (1.42 fold). The optimised conditions for SSF after CCD were: temperature of 35 °C, initial pH of 5.5, cellulase loading of 15 FPU/g-substrate and substrate concentration of 5% (w/v). This optimisation study resulted in 55.95% increment (2.14 fold) of biobutanol concentration equivalent to 3.97 g/L and biobutanol yield of 0.16 g/g. The model and optimisation design obtained from this study are important for further improvement of biobutanol production, especially in consolidated bioprocessing technology.

Malaysia has a vast amount of tropical agricultural land that suitable for various agricultural activities. A lot of biomass generated from the agricultural activities such as rubber, paddy, fruit and oil palm biomass. Oil palm empty fruit bunch (OPEFB) has been recorded as one of the largest oil palm biomass (18–19 million tonnes/year) produced in palm oil processing mill. OPEFB has the potential as substrate for biobutanol production due to its abundance, cheap and high holocellulose content, thus provide renewability and environmentally friendly biobutanol compared to fossil fuels. Process for biobutanol production from OPEFB can be classified into two major processes: (i) separate saccharification and fermentation (SHF) and (ii) simultaneous saccharification and fermentation (SSF). SSF is a process where the enzymatic saccharification of OPEFB and ABE fermentation are carried out simultaneously in a flask. SSF process has recently gained attention and was proven to be more feasible than SHF, as it reduces the needs for additional equipments therefore lowering in capital, operational costs and time. The main disadvantage of the SSF process is the optimum temperature for fermenting Clostridia (37°C) does not coincide with the optimum temperature for cellulase (50°C). Thus, the objective of this study was to improve the biobutanol production through SSF using OPEFB. The optimisation study consisted of two main parts that employed; one factor at a time (OFAT) approach and using Central Composite Design (CCD) by Response Surface Methodology (RSM). The SSF process successfully produced maximum biobutanol concentration of 1.74 g/L and biobutanol yield of 0.070 g/g at 96 h. The SSF biobutanol yield was comparable to the SHF biobutanol yield of 0.078 g/g. The SSF process was further enhanced by studying the preliminary investigation by OFAT approach. The results generated maximum biobutanol concentration of 2.91g/L and biobutanol yield 0.12 g/g. The percentage of biobuta

Nowadays, too much pollution is happening surrounding us and one of them is water pollution which each becoming more severe and worse every day. One of the sources of water pollution comes from the industry which used dyes either excessively or not. In this particular case, the wastewater needs to be treated before releasing into the river or environment. Titanium dioxide (TiO2) is one of the most powerful semi-conductors that chemically stable and widely used in the photodegradation of wastewater process. However, TiO2 has wide band gap (3.2 eV) which only can be activated by using UV light. In order to overcome the weakness of this photocatalyst, doping technique is applied to modify the TiO2. By doping technique, the band gap can be reduced and the modified TiO2 can be applied under the visible light. The objectives of this research are to synthesise and analyse the characteristics of photocatalysts N-TiO2 and Mg-TiO2 on the phase and the morphology. Then, the objective is also to determine the maximum decolourisation efficiency on photodegradation Reactive Black 5 (RB 5) by N-TiO2 and Mg-TiO2 under visible light. In this research project, nitrogen and magnesium were used as dopants and sol-gel method is applied. Calcination temperatures were varied at 300 oC, 500 oC and 700 oC in order to analyse the phase and characteristics of samples at different calcination temperature. The results obtained from the experiment showed the band gap after doping for samples 0.5 wt.% Mg-TiO2 and N-TiO2 shifted to the lower value compared to the theory value of pure TiO2 (3.2 eV) which are between 2.75 eV-2.98 eV . The phase structure of N-TiO2 and Mg-TiO2 at 300 oC and 500 oC were observed as pure anatase and at 700 oC , a mixture of anatase and rutile were found. The decolourisation of RB 5 achieved the highest efficiency at 83.46 % for 0.9 wt.% N-TiO2 and 72.66 % for 0.7 wt.% Mg-TiO2. Kinetic studies of zero order, first order and pseudo-first order were tested and it was foun

Dyes have complex chemical structure and cannot be treated easily. Many industries applied dyes in their production, however the wastewater is not properly treated. This can lead to major water pollution if the problem is not overcome. One of the effective method is using photocatalytic degradation as it is environmental friendly and low cost. Sol-gel method used in order to produce the N-doped titanium dioxide photocatalyst with the presence of titanium isopropoxide (TTIP) and all the samples were calcined at different temperature of 300oC, 500oC and 700oC. At calcination temperature of 300oC and 500oC, pure anatase phase were shown and all rutile phase were shown when the samples were calcined at 700oC. This is due to the transformations of anatase phase to rutile and brookite happened at higher temperature. The crystallites size also affected by the calcination temperature which it was found that the size of N-doped TiO2 at 300oC is 7.4686nm, and at 500oC and 700oC showed crystallite size of 12.653nm and 54.7170nm respectively. The bandgap study showed that all samples were shifted from UV light region to visible light region which is normally <3.2 eV for commercial anatase titanium dioxide. The significant of the study is to enhance the sol-gel method to form effective photocatalyst in order to achieve higher degradation rate. The photocatalytic process shown at higher rate when N-doped TiO2 annealed at 300oC.

Herein, we propose a seed-mediated growth method for synthesis of gold nanorices directly grown on the substrate using silver seed. The as prepared sample was characterized using UV-Vis spectrometer, field emission scanning electron microscopy (FESEM), and X-Ray diffraction (XRD). The UV-Vis spectrum of the sample shows transversal surface plasmon resonance (t-SPR) peak at wavelength 541 nm and longitudinal surface plasmon resonance (l-SPR) peak at wavelength 730 nm. The FESEM image confirmed the morphology of gold nanostructures are rice-like shape. Typically, the nanorices have long axis (a) 55.54±3.30 nm, short axis (b) 28.71±2.30 nm, and aspect ratio (a/b) 1.98±0.09. The XRD pattern of the sample at diffraction angle (2θ) in the range of 10º-70º reveals three peaks at 38.18º, 44.48º, and 64.67º which corresponding to (111), (200), and (220) Bragg’s reflection of face centers cubic lattice Gold (ICSD file No. 98-005-3763). The strong peak intensity at 38.18º represents the nanorices growth in the (111) direction. The gold nanostructures with rice-like shape which exhibit two localized surface plasmon resonance (LSPR) thus it has very potential for application in plasmonic sensing

Simultaneous saccharification and fermentation is a feasible process for biobutanol production. Biobutanol serves as alternative to the depleting fossil fuels source and also environmental friendly. Oil palm empty fruit bunch (OPEFB) is one of the renewable lignocellulosic biomass that can be utilized as substrates in the process. Simultaneous saccharification and fermentation incorporates one-step addition of microorganism, cellulase enzymes and biomass in a vessel. The simultaneous system works by employing Clostridium acetobutylicum ATCC 824 with Acremonium cellulase to hydrolyze 2% NaOH alkali pretreated OPEFB with autoclave. Enhancement of simultaneous saccharification and fermentation through one factor at a time followed by statistical analysis using Response Surface Methodology (RSM) aimed for high yield of biobutanol. The system will further undergo scaling up process. This research is expected to contribute to fuel sustainability in the future.

An investigation on composition and seasonal occurrence of shrimp post larvae was conducted in the Matang Mangrove Reservation Forest Perak, Malaysia during wet season (November 2015 to January 2016) and dry season (June 2015 to August 2015). There were three sampling stations, Station 1 (MO) at Sungai Tiram Laut, which the least disturbed mangrove, Station 2 (MT) at Sungai Tinggi, moderately disturbed mangrove and Station 3 (MS) at Sungai Sepetang which considered as a most disturbed mangrove area. None of the water parameters showed significant difference (p>0.05) among stations except only for water salinity (p<0.05). In total of 11682 individual was observed during the study period. There were four major taxa were identified namely Lucifer (23%), Acetes (3.8%), Mysid (1.7%) and Odontodactylus (0.1%) and the rest is unidentified (66.32%). The overall mean density of shrimp post larvae (PL) was calculated as 18.36 individuals/100 m3 in the investigated area. None of the diversity indices showed significant variation among the stations (p>0.05). However, all diversity indices of shrimp post larvae in study area shows statistically significant (p<0.05) difference between the wet and dry season.

Kajian ini memberi penelitian terhadap ujaran yang berlaku dalam kalangan masyarakat Banjar di Selangor. Objektif kajian ini adalah untuk mengenal pasti dan membincangkan ujaran dalam kalangan masyarakat Banjar dari sudut semantik dan pragmatik. Sampel kajian terdiri daripada beberapa buah keluarga di Pulau Carey, Kuala Langat, Selangor. Kajian ini menggunakan pendekatan kualitatif yang terdiri daripada kaedah pemerhatian dan temu bual. Teknik kajian adalah dengan menemu bual setiap keluarga dan merakam perbualan mereka ketika mereka berkumpul untuk sambutan perayaan, majlis bertunang dan kenduri kahwin. Seterusnya, transkrip perbualan dianalisis dari sudut pragmatik dengan menggunakan Teori Relevans oleh Sperber dan Wilson (1986). Hasil kajian mendapati makna ujaran dapat dianalisis dengan jelas apabila ilmu pragmatik diaplikasikan. Hal ini kerana, ilmu pragmatik mampu mengungkapkan makna yang disampaikan berdasarkan konteks situasi yang sebenar. Bagi memahami makna sesuatu ujaran, beberapa aspek seperti konteks, kesan konteks dan kos memproses perlu dilihat berdasarkan Teori Relevans. Oleh itu, makna sesuatu ujaran bergantung kepada konteks dan situasi sebenar yang dapat dimanifestasikan.