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Microplastics (MPs) pose a threat to ecosystems due to their capacity to bind with toxic chemicals. While the occurrence of MPs in aquatic environmental matrices like water, sediments, and biota is well studied, their presence in the atmosphere remains less understood. This study aimed to determine the presence of airborne MPs and their characteristics through ground-based sampling in the coastal city of Kuala Nerus, Terengganu, Malaysia. Airborne MP samples were collected using passive sampling technique in December 2019. MPs were manually counted and identified using a stereomicroscope based on their colour and shape. The average deposition rate of airborne MPs during the sampling period was 5476 ± 3796 particles/m2/day, ranging from 576 to 15,562 particles/m2/day. Various colours such as transparent (38%), blue (25%), black (20%), red (13%), and others (4%) were observed. The predominant shape of airborne MPs was fibres (> 99%). The morphology structure of MPs observed using a scanning electron microscope (SEM) showed a cracked surface on MPs, suggesting weathering and irregular fragmentation. Further elemental analysis using energy dispersive X-ray spectroscopy (EDS) showed the presence of heavy metals such as aluminium (Al) and cadmium (Cd) on the surface of MPs, attributed to the adsorption capacities of MPs. Polymer types of airborne MPs were analysed using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), which revealed particles composed of polyester (PES), polyethylene (PE), and polypropylene (PP). The preliminary findings could provide additional information for further investigations of MPs, especially in the atmosphere, to better understand their sources and potential human exposure. [ABSTRACT FROM AUTHOR]

A comparative study of foliar trichomes for selected Asteraceae collected in Pahang was observed. The selected species were Ageratum conyzoides L., Tridax procumbens L., Eclipta prostrata (L.) L., Sphagneticola trilobata (L.) Pruski, Emilia sonchifolia (L.) DC. and Youngia japonica (L.) DC. The objective of this study is to document various trichomes among selected Asteraceae species in Pahang. Trichomes are known as one of the micromorphological characteristics that can be investigated for the assisting identification of Asteraceae. The trichomes were examined under a light microscope and Scanning Electron Microscopy (SEM). The trichomes in this study were classified into eight types. The diagnostic characteristics in Ageratum conyzoides consist of glandular trichomes while the non-glandular trichomes are mostly shown in Tridax procumbens. Tridax procumbens showed four diagnostic characteristics which are simple multicellular trichome (coned shape), simple multicellular trichome (long, pointed-end), simple multicellular trichome (long, tapered-end), and stellate trichome. This study proved that data from plant anatomy can be used as supporting data for plant classification in Asteraceae. [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]

Soil is a heterogeneous material, and its properties are vital from an agricultural perspective and for groundwater management. However, limited studies have been performed on the soil characteristics (soil texture, water-holding capacity, and soil compositions) of a single pumping well, especially in Malaysia. This article focuses on the soil characteristics and elemental analysis of a single borehole with 11 samples collected around Labu Kubong, Perak. The soil properties were analyzed in the context of particle size distribution (PSD) using the laser diffraction method (LDM), as well as soil composition for elemental analysis using a scanning electron microscope coupled with an energy dispersive X-ray (SEM-EDX). The LDM results revealed the average percentage of clay, silt, and sand to be 0%, 6%, and 94%, respectively, indicating most particles comprised sand particles which in percentages demonstrated a sandy texture with less silt content. Additionally, the water holding capacity is low because of major coarse sand particles in alluvial formations. Moreover, SEM-EDX outcomes displayed an average percentage of elemental composition reported as follows: C (40.77%), O (34.33%), Si (10.66%), Al (5.82%), Fe (1.10%), K (1.10%), As (0.05%), Na (0.04%), and Be (5.62%). Consequently, SEM-EDX outcomes showed these elements were derived from silicified quartz, feldspar, and iron-bearing minerals that originated from shale formations, and the presence of carbon indicates peat formation. Therefore, this study provides information on a single pumping well from an irrigation practice, and this study also recommends regional to global scale studies for supporting sustainable groundwater development worldwide. [ABSTRACT FROM AUTHOR]

The growth of Malaysia has caused many industries to grow rapidly, especially construction industries due to the demand for more homes, buildings, and infrastructure. The production of concrete and mortar is highly requested. Therefore, the demand for fine aggregate becomes higher because fine aggregate is one of the main elements in concrete and mortar production. The high demand for fine aggregates will create a worrying situation where the fine aggregate crisis will worsen. An alternative was introduced to replace the fine aggregate known as palm oil fuel ash (POFA) in order to reduce the use of natural resources such as fine aggregates and lead to the reduction of fine aggregate mining activity. POFA produced from palm oil fibre, palm oil shell, and mesocarp at high temperature has no benefits in the commercial return. Thus, POFA that has accumulated in landfill has the ability to create environmental pollution. Due to the pozzolanic behaviour of POFA, it could be relevant when POFA is used in the production of mortar as a partially fine aggregate replacement. There is a limited study on the effects of POFA as a partially fine aggregate replacement in the production of mortar. The aim of this research is to study the effects of POFA on the workability of fresh mortar, and for the hardened mortar, compressive strength and microstructural analysis will be analysed. A total of 45 cubes with dimensions of 100 mm × 100 mm × 100 mm were cast at different percentages of POFA at 0%, 2.5%, 5%, 7.5%, and 10% by the weight of fine aggregates. Slump and flow table tests were conducted during the casting process to determine the workability. All the specimens were water cured at days 3, 7, and 28 before being tested with a compression test and scanning electron microscope (SEM) on the hardened mortar. It was discovered that 0% POFA recorded the highest workability. Furthermore, the laboratory results showed that the 2.5% POFA in the mortar recorded the highest compressive strength compared to other specimens. Moreover, the microstructure of the mortar specimen was observed to be denser, and the pores were refined with the presence of POFA, compared to the control specimen. Based on the findings, this research enables us to give an understanding of the effect of POFA incorporated in mortar as a partially fine aggregate replacement in terms of workability, compressive strength, and microstructural analysis. Based on the results from this research, the advantage of POFA can be fully utilized and can help reduce the environmental problems. [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]

• 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]

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]

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]

Marine pollen records from the southern South China Sea (SCS) have yielded critical information regarding epicontinental vegetation succession since the last glacial period, which involves understanding the role of tropical rainforests in driving climate change. However, the rich biodiversity and pollen taxa in Southeast Asia are challenging for palynological work, such as detecting pollen signals from various vegetation types and tracing the source areas of pollen grains deposited in the ocean; therefore, improving the taxonomic level of fossil pollen identification is significantly crucial for pollen analysis in tropical regions. To enrich modern pollen references of Southeast Asia, we observed the pollen morphology of 124 identified species (111 genera and 42 families) from tropical Malaysia using a light microscope and scanning electron microscope (SEM). The results show 19 pollen morphotypes, of which the tricolporate type occurs in half of the samples, reflecting the complexity of fossil pollen classification and identification. Pollen sculpture and aperture details of the selected taxa are clearly shown under SEM, which significantly improves the morphological understanding of tropical pollen (e.g., fabaceae , euphorbiaceae , and rubiaceae). This result presents the potential of extracting unique pollen signals to distinguish different vegetation types that contain many common species in Southeast Asia. It highlights the significance of improving pollen identification levels to clarify whether there was a widespread rainforest on the exposed continental shelf during the last glacial period in the southern SCS. • This study showed exine ornamentation and aperture details of the 19 pollen taxa in 124 tropical species. • We improved the identification level for fabaceae , euphorbiaceae , and rubiaceae pollen with high diversity. • This study presented the potential of extracting unique pollen signals to distinguish different vegetation types. [ABSTRACT FROM AUTHOR]