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An in-depth understanding on the structural features of engineered magnetic adsorbent is important for forecasting its efficiencies for environmental clean-up studies. A magnetic kaolinite nanocomposite (MKN) was prepared using Malaysia's natural kaolinite via co-precipitation method with a three different clay: iron oxide mass ratio (MKN 1:1, MKN 2:1 and MKN 5:1). The morphology and structural features of the magnetic composites were systematically investigated using techniques, such as: Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), surface area analysis (BET), Vibrating Sample Magnetometer (VSM), and zeta potential measurement. The removal efficiencies of the adsorbent for Methylene Blue (MB) dye were studied in batch method as a function of pH and initial concentration. MKN1:1 demonstrated the highest magnetisation susceptibility (Ms) of 35.9 emu/g with four-fold-increase in specific surface area as compared to the pristine kaolinite. Preliminary experiment reveals that all MKNs showed almost 100% removal of MB at low initial concentration (<50 ppm). The spent MKN adsorbent demonstrated an easy recovery via external magnetic field separation and recorded maximum adsorption capacity of 18.1 mg/g. This research gives an insight on the surface characteristics of magnetic clay composite for potential application as an effective and low-cost adsorbent in treating dye contaminated water. [ABSTRACT FROM AUTHOR]

• Ultrasound-assisted chemical pretreatment was applied to durian peel. • Characterization using SEM, FTIR and XRD. • Ultrasound intensified the solubilization of lignin and hemicellulose. • Ultrasound plus alkaline pretreatment produced highest fermentable sugar. Durian peel, an abundant waste in Malaysia could be a potential substrate for fermentable sugar recovery for value-added biochemical production. Common pretreatment such as acid or alkaline pretreatment resulted in the need for extensive solid washing which generated wastewater. Herein, this study aims to introduce sonication on top of chemical pretreatment to destruct lignin and reduce the chemical usage during the durian peel pretreatment process. In this study, the morphology and the chemical composition of the pretreated durian peels were studied. The sugar yield produced from the chemical pretreatment and the combined ultrasound and chemical pretreatment were compared. The morphology and chemical structure of durian peels were investigated by Scanning Electron Microscope (SEM), Fourier Transform Infrared (FTIR) analysis and X-ray diffraction (XRD). The SEM images showed that the structural change became more significant when sonication was introduced. Second, XRD profile indicated a relatively higher crystallinity index and FTIR spectra displayed a lower intensity of lignin and hemicellulose for ultrasound plus alkaline (UB) pretreatment as compared to acid, alkaline and ultrasound plus acid (UA) pretreatment. UB and UA pretreatment portrayed higher yield (376.60 ± 12.14 and 237.38 ± 3.96 mg reducing sugar/g dry biomass, respectively) than their controls without the application of ultrasound. Therefore, it could be concluded that ultrasound was able to intensify the fermentable sugar recovery from durian peel by inducing physical and chemical effect of cavitation to alter the morphology of durian peel. Fermentation of UB treated durian peel resulted in 2.68 mol hydrogen/mol consumed sugar and 131.56 mL/L medium /h of hydrogen productivity. This study is important because it will shed light on a way to handle durian waste disposal problems and generate fermentable sugars for the production of high value-added products. [ABSTRACT FROM AUTHOR]

This study focused on the reclamation of ash from incineration process and development of new artificial lightweight aggregate (LWA) that have comparable properties with existing natural coarse aggregate. the main objective of this study is to examine potential use of recycled municipal solid waste incineration (MsWi) ash as raw material in lWa production with a method of cold-bonded pelletization. two types of incineration ash which is bottom ash (BA) and fly ash (FA) were collected from Cameron highland incineration Plant, Malaysia. the properties of ba and Fa are studied by means of X-ray Fluorescence (XRF) and microstructure of these ashes were inspected using scanning electron Microscope (SEM). the properties of bala and Fala produced in this study is examined including loose bulk density, water absorption and aggregate impact value (AIV). From the results of both types of artificial lWa, the lowest loose bulk density of bala is bala50 with 564.14 kg/m³ and highest is at 831.19 kg/m³. For Fala50, lowest loose bulk density is 573.64 kg/m³ and highest is 703.35 kg/m³. Water absorption of bala and Fala is quite similar with one another in with the value of 23.8% and 22.6%, respectively. Generally, Fala have better qualities of lWa comparing with bala with lower bulk density and water absorption and can be categorized as strong aggregate. in summary, reclamation and reutilization of incinerator ash has generated acceptable qualities for artificial lWa. both types of ba and Fa shown a great potential to be recycled as additional materials in artificial aggregate production. [ABSTRACT FROM AUTHOR]

Rafflesia is a holoparasitic plant that depends solely on its host for its nutrients, given that during the early stage of its life, this parasite lives inside the host vine. The lack of host specificity and preference information for Rafflesia can largely be attributed to the absence of a comprehensive taxonomic study in Tetrastigma. Without the host, the Rafflesia will not be able to survive. Therefore, this research was conducted to study the host-parasitic relationships between the two species using anatomical dissection and micrographic images using a light microscope (LM) and scanning electron microscope (SEM). The anatomical study consisted of three stages of Rafflesia buds; the emergence of cupule stage, cupulebract transition stage, and bract stage attached with the host. All samples underwent sliding techniques and were observed using LM and SEM. Based on the results, the anatomical characteristics of the host-parasite for the cupule stage evidenced penetration of the parasite-affected tissues inside the vascular bundles with the visibility of the flower bud. However, during other stages, the penetration of parasite-affected tissues to the vascular bundles was disrupted and cannot be seen using this sliding technique. The endoparasite of Rafflesia invades the host only towards the phloem region in the early stage. In contrast, in late buds for both species, the Rafflesia tissue invaded both the host xylem (proximal region) and phloem. The parasite intrusion movement for both Rafflesia species showed a pointed tissue towards the host as this was believed to minimise the damage of the host plant. A new method using the paraffin wax technique might improve the sectioning and provide a more precise relationship dissection. The information from this study is expected to provide baseline information and an understanding of the host-parasitic relationship between the species. In addition, further anatomical studies with the different stages of buds will offer a better understanding of their relationship with the host. [ABSTRACT FROM AUTHOR]

Formation of carbonate minerals by CO2 sequestration is a potential means to reduce atmospheric CO2 emissions. Vast amount of alkaline and alkali earth metals exist in silicate minerals that may be carbonated. Laboratory experiments carried out to study the dissolution rate in Pahang Sandstone, Malaysia, by CO2 injection at different flow rate in surficial condition. X-ray Powder Diffraction (XRD), Scanning Electron Microscope (SEM) with Energy Dispersive X-ray Spectroscopy (EDX), Atomic Absorption Spectroscopy (AAS) and weight losses measurement were performed to analyze the solid and liquid phase before and after the reaction process. The weight changes and mineral dissolution caused by CO2 injection for two hours CO2 bubbling and one week' aging were 0.28% and 18.74%, respectively. The average variation of concentrations of alkaline earth metals in solution varied from 22.62% for Ca21 to 17.42% for Mg21, with in between 16.18% observed for the alkali earth metal, potassium. Analysis of variance (ANOVA) test is performed to determine significant differences of the element concentration, including Ca, Mg, and K, before and after the reaction experiment. Such changes show that the deposition of alkali and alkaline earth metals and the dissolution of required elements in sandstone samples are enhanced by CO2 injection. [ABSTRACT FROM AUTHOR]

Pandanus amaryllifolius is a member of Pandanaceae family and is abundant in south-east Asian countries including Malaysia, Thailand, Indonesia and India. In this study, Pandanus amaryllifolius fibres were extracted via a water retting extraction process and were investigated as potential fibre reinforcement in polymer composite. Several tests were carried out to investigate the characterization of Pandanus amaryllifolius fibre such as chemical composition analysis which revealed Pandanus amaryllifolius fibre's cellulose, hemicellulose and lignin content of 48.79%, 19.95% and 18.64% respectively. Material functional groups were analysed by using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction analysis confirming the presence of cellulose and amorphous substances in the fibre. The morphology of extracted Pandanus amaryllifolius fibre was studied using a scanning electron microscope (SEM). Further mechanical behaviour of fibre was investigated using a single fibre test with 5 kN cell load and tensile strength was found to be 45.61 ± 16.09 MPa for an average fibre diameter of 368.57 ± 50.47 μm. Meanwhile, moisture content analysis indicated a 6.00% moisture absorption rate of Pandanus amaryllifolius fibre. The thermogravimetric analysis justified the thermal stability of Pandanus amaryllifolius fibre up to 210 °C, which is within polymerization process temperature conditions. Overall, the finding shows that Pandanus amaryllifolius fibre may be used as alternative reinforcement particularly for a bio-based polymer matrix. [ABSTRACT FROM AUTHOR]