Browsing by Type "book-chapter"
  • Publication
    3 Nanocellulose: from biosources to nanofiber and their applications
    (De Gruyter, 2023)
    Rushdan Ahmad Ilyas
    ;
    Norfarhana Abd Samad
    ;
    Abu Hassan Nordin
    ;
    Siti Nor Hawanis Husain
    ;
    Asmawi Nazrin
    ;
    Salit Mohd Sapuan
    ;
    Razali Mohamad Omar Syafiq
    ;
    Pui San Khoo
    ;
    Abdoulhdi A. Borhana Omran
    ;
    Dominic C. D. Midhun
    ;
    Nasmi Herlina Sari
    ;
    Melbi Mahardika
    ;
    Mochamad Asrofi
    ;
    Hairul Abral
    Nanocellulose is a product of cellulose, a sustainable and plentiful resource. It's distinctive nanoscale structure makes it a versatile, green and interesting material for a variety of applications. This article describes in detail the biosources of nanocellulose, the types and characteristics of nanocellulose, and the techniques used to produce nanocellulose fibers. The mechanical properties and morphologies of nanocellulose fibers are addressed in depth, along with their prospective applications in sectors, including paper packaging, building materials, composites, biomedicine, energy storage and filtration. In addition, the current state of nanocellulose research, including the opportunities in the field, as well as the future prospects of nanocellulose as a viable and sustainable material for a vast array of applications, are discussed. © 2023 Walter de Gruyter GmbH, Berlin/Boston. All rights reserved.
      7  17
  • Publication
    Assessment of sludge-based microbial fuel cell performance via electrochemical impedance spectroscopy
    (Springer, 2023-06)
    Mohamad Farhan Mohamad Sobri
    ;
    Muhammad Hazwan Hussin
    ;
    Muaz Mohd Zaini Makhtar
    The effective, non-destructive method known as electrochemical impedance spectroscopy (EIS) can be a useful supplement to the methods currently being used to examine microbial fuel cells (MFCs). Its use in MFC research should be investigated further, such as in the examination of MFC internal resistance, electrode materials, catalyst coatings on electrodes and growth of biofilms. Specifically, this chapter details the application of EIS in comprehending electro-chemical processes involved in sludge-based MFC, the biological and/or abiotic variables that restrict power production, with the goal of comprehending and overcoming them.
  • Publication
    Biodegradable natural fiber polymer composite as future 3D printing feedstock
    (CRC Press, 2023)
    Sanusi Hamat
    ;
    Mohamad Ridzwan Ishak
    ;
    Mohd Sapuan Salit
    ;
    Noorfaizal Yidris
    The key advantages of 3D printing are its capability to produce complex structures and rapid prototyping. This has contributed to the development of modern material processing methods over the past years for industrial tasks and needs. However, the development of biodegradable feedstock for 3D printing filament and enhanced natural fiber as reinforcement filler to improve mechanical properties and biodegradation is still not fully explored. Also, there have been alarming concerns around the world about the use of non-biodegradable resources during 3D printing that could threaten the sustainable environment. This review discusses the types of biodegradable polymers, natural fibers with their properties and applications, the development method for non-biodegradable and biodegradable polymer composites obtained through fused filament fabrication (FFF). Finally, the challenges and future opportunities associated with 3D printing feedstock of biodegradable polymer composites are reviewed and analyzed.
      1  13
  • Publication
    Comparison between natural rubber, liquid natural rubber, and recycled natural rubber as secondary matrix in epoxy/natural rubber/graphene nano-platelet system
    (Springer International Publishing, 2023)
    K. W. Kam
    ;
    Teh Pei Leng
    ;
    Yeoh Cheow Keat
    A comparison is made between the effects of natural rubber (NR), liquid natural rubber (LNR), and recycled natural rubber (rNR) in the filled epoxy systems on the physical, mechanical, thermal, and electrical performances of filled epoxy systems. The results show that flexural strength and modulus values were improved. The toughness properties of the filled epoxy system were enhanced with NR phases (72 MPa, 2317 MPa, 4.2 MPa. m1/2), as compared to those with LNR (55 MPa, 2100 MPa, 3.2 MPa. m1/2) and rNR (52 MPa, 2000 MPa, 2.3 MPa. m1/2) at 5 vol.%. Scanning electron micrograph (SEM) analysis revealed that the particle sizes of NR phases dispersed within the epoxy matrix were smaller and more uniform (0.29-1.65 μm) as compared to those with LNR (0.64-3.57 μm) and rNR (≥250 μm) phases. The incorporation of NR, LNR, and rNR phases improved the thermal stability of the filled system. This is attributed to more heat energy being needed to overcome good interfacial bonding between epoxy matrices and the small NR phases. X-ray diffraction analysis results showed that the filled epoxy/NR/GNP system has higher 2θ values, indicating that d-spacing in GNP nano-fillers has the closer distance. Electrical bulk conductivity values of filled epoxy/NR/GNP systems were the highest, 4.50 x 10-3 1/Ω. cm at 20 vol.%. Small NR phases acted as elastomer spacers, which provided better GNP packing efficiency and realigned the GNP nano-fillers to form more effective conductive pathways for electron transport.
  • Publication
    E-Nose: spoiled food detection embedded device using machine learning for food safety application
    (Springer, 2024)
    Wan Nur Fadhlina Syamimi Wan Azman
    ;
    Ku Nurul Fazira Ku Azir
    ;
    Adam Mohd Khairuddin
    This research aims to employ machine learning (ML) to classify the degree of contamination in leftover cooked foods based on their smell. This study evaluates the odour characteristics of typical leftover cooked lunch or dinner meals that are consumed locally in Malaysia. An easy-to-use e-nose application was attached to the food containers, consisting of four different types of sensors sensitive to various gases, to collect the data. RStudio is used to analyze samples in order to identify the odour classification of leftover Malaysian food. The accuracy ranged from 90% to 100% when using the oversampling and undersampling techniques. The results of this re-search showed satisfactory performances by Support Vector Machines (SVM) is superior compared to that of k-Nearest Neighbours (k-NN) in classifying the samples’ contamination degree. As a result, the findings showed that the electronic nose used in this study was a promising method for classifying the degree of contamination in leftover cooked foods and predicting whether food is still edible or not. © 2024, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
  • Publication
    Formation of bioresorbable PCL-loaded Moringa Oleifera L./Natural clay functional particles by solvent displacement method for pharmaceutical applications
    (Springer, 2024)
    Monisha Devi
    ;
    Rahimah Othman
    ;
    Mohd Irfan Hatim Mohamed Dzahir
    ;
    Siti Pauliena Mohd Bohari
    Bioresorbable functional particles offer unique advantages based on different synthetic strategies, with the activated moiety may achieve various targeted drug delivery to minimize side effects. Thus, in this study, a highly MO-loaded adsorptive smart-assembled natural clay (montmorillonite, MMT) dispersion onto poly (ε-caprolactone) nanoparticles matrix (hereafter known as MO-loaded MMT/PCL NPs) is formed by solvent displacement method. MMT is selected due to its great drug loading ability due to high specific surface area and grants mucoadhesive properties with tortuous pathway needed for drug delivery across the gastrointestinal barrier. The MO-loaded MMT/PCL NPs are synthesized by self-solvation interaction between the organic phase that composed of dissolved 1 g L−1 PCL, 2–20 wt % of MMT, and 0.6–3.0 g L−1 of MO in acetone and the aqueous phase consisted of 0.2 wt% poly (vinyl alcohol) surfactant solution. The injection rate of organic phase was fixed at 5 mL min−1 with volume ratio aqueous phase to organic phase (Vaq/Vor) between 3–10, and 600–1200 rpm of stirring speed. The inclusion of MMT in polymer was found to improve the entrapment of hydrophilic MO, hence hindering untimely drug leakage. Particle size decreased with increasing the stirring rate and the aqueous-to-organic volumetric ratio as well as the concentration MMT, thus resulting in drug encapsulation efficiency and drug loading up to 30–50 and 5–10%, respectively. The encapsulation of MMT and MO in the NPs was confirmed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy.
  • Publication
    Malaysian seashells based Hydroxyapatite for biomedical application
    (Springer Nature, 2023)
    Nur Farahiyah Mohammad
    ;
    Mohd Riza Mohd Roslan
    ;
    Nashrul Fazli Mohd Nasir
    Hydroxyapatite (HA, Ca10 (PO 4 ) 6 (OH) 2 ) is widely used in dentistry and orthopaedics as a bone substitute or replacement material. The material is chemically and crystallographically identical to the mineral component of human biological bone. Natural materials such as animal bones, clay, eggshells, corals, and seashells can be used as a main source of calcium precursor to synthesise HA. Using Malaysian shell waste materials is sustainable and economical. Thus, these advantages have attract researchers to explore potential products from shell trash. This chapter presents the synthesis method and characterisation of hydroxyapatite synthesised from several Malaysian local seashells such as Paphia textile (lala), Corbiculacea (etok), and Polymesoda expansa (lokan) shells.
      1  18
  • Publication
    Mechanical performance of natural fiber-reinforced alkali-activated composites
    (Elsevier, 2023)
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Pilomeena Arokiasamy
    ;
    Fatin Farhana Kamarzaman
    Alkali-activated material exhibits brittle behavior with low tensile strength and is sensitive to cracking which also affect the durability of the structures. To address this issue, alkali-activated material is frequently made into alkali-activated composites (AACs) by using by fiber reinforcement. Natural fibers have a number of advantages, including lightweight, high strength, and safety in use and processing compared to synthetic fiber. The developed natural fiber-reinforced cementitious composites exhibit outstanding flexural, fracture, and impact resistance. However, the chemical incompatibility that may exist between cement and fiber is the main problem for natural fiber-reinforced cement composites. The pyrolytic behavior of natural fibers can be viewed as a multiconditional coupling in a cement-based environment with high alkalinity and a large variety of mineral species. Thus this review provides in depth analysis on the diverse natural fiber and its utilization in the development of fiber-reinforced AACs (FRAACs). Hence, this would guide in finding the best fiber source for the development of high mechanical strength FRAAC to meet building and construction application.
  • Publication
    Tensile, thermal properties, and biodegradability test of paddy straw powder-filled Polyhydroxybutyrate-3-Valerate (PHBV) biocomposites: acrylation pretreatment
    (Springer International Publishing, 2023)
    Noorulnajwa Diyana Yaacob
    ;
    Hanafi Ismail
    ;
    Sam Sung Ting
    The mechanical, thermal, and biodegradability properties of paddy straw powder (PSP)-filled polyhydroxybutyrate-3-valerate (PHBV) biocomposites were investigated. The impacts of chemical alteration of PSP via acrylic acid treatment were examined as well. The outcomes of the study portrayed a decrease in the elongation at break and tensile strength when the filler loading increased; however, the modulus elasticity of composites could be seen to increase. Chemical alteration of PSP via acrylic acid enhanced modulus elasticity of the biocomposites and tensile strength; nevertheless, the elongation at break was decreased. Thermogravimetric analysis demonstrated the enhancement of thermal stability of the biocomposites via PSP compared to neat PHBV. The thermal stability of the biocomposites was positively affected by chemical alteration of PSP. Meanwhile, DSC analysis proved that the melting temperature (T m) of the biocomposites was not altered when the filler was added. Treated biocomposites demonstrated higher crystallinity (30.18%) compared to the untreated composites (26.24%). Biodegradability test showed the strains from both Aspergillus species have the potential to degrade PHBV/PSP biocomposites. The weight loss of biocomposites after undergoing fermentation with Aspergillus fumigatus strain SGE57 and Aspergillus niveus isolate A17 was 2.42% and 3.65%, respectively.
      19  3