UniMAP RIS :: Browsing Publications 2024 by Issue Date

Publication

Design and Simulation of a Customize Three-axis Gimbal Structure using Finite Element Analysis Method

( 2023-03-01)

Kamaruzzaman M.A.

;

Basri H.H.

;

Ayob M.N.

This paper presents a Finite Element Analysis (FEA) on a customized three-axis gimbal design application. Examples of applications of the gimbals such as drones, camera stabilizers, and spacecraft. The SolidWorks software checked the gimbal’s FEA characteristics with no existing load or normal conditions. Using the FEA method, a static simulation analysis where the material of this assembly design uses Polylactic Acid (PLA), used mainly by 3D printer machines. The force is given to the gimbal structure and obtains the results of the maximum value of stress in MPa, displacement in mm, and strain. Thus, based on the results obtained from SolidWorks, the structure will not fail. The maximum stress value between parts is 2.31 MPa for the support part and 3.09 MPa for the assembly model when the yield stress value of the PLA material properties is at 70 MPa. The new design structure for the gimbal hardware focuses on academic purposes based on PLA material and is easy to build using a 3D printer. In the summary, the customized three-axis gimbal design using SolidWorks will not fracture when the design is in normal condition which has a total force of 6.87 N, which is equal to 0.70 kg at 3.09 MPa where the weight of the base, O-ring, and servo motors at the U-shape part. In addition, the design can hold up to 230.87 N, which is equal to 23.54 kg at 69.90 MPa of the stress value before it will fail at 70 MPa.

1

Publication

An update on pathogenesis and clinical scenario for Parkinson’s disease: diagnosis and treatment

( 2023-05-01)

Adam H.

;

Subash Chandra Bose Gopinath

;

Mohd Khairuddin Md Arshad

;

Tijjani Adam

;

Parmin N.A.

;

Husein I.

;

Uda Hashim

In severe cases, Parkinson’s disease causes uncontrolled movements known as motor symptoms such as dystonia, rigidity, bradykinesia, and tremors. Parkinson’s disease also causes non-motor symptoms such as insomnia, constipation, depression and hysteria. Disruption of dopaminergic and non-dopaminergic neural networks in the substantia nigra pars compacta is a major cause of motor symptoms in Parkinson’s disease. Furthermore, due to the difficulty of clinical diagnosis of Parkinson’s disease, it is often misdiagnosed, highlighting the need for better methods of detection. Treatment of Parkinson’s disease is also complicated due to the difficulties of medications passing across the blood–brain barrier. Moreover, the conventional methods fail to solve the aforementioned issues. As a result, new methods are needed to detect and treat Parkinson's disease. Improved diagnosis and treatment of Parkinson's disease can help avoid some of its devastating symptoms. This review explores how nanotechnology platforms, such as nanobiosensors and nanomedicine, have improved Parkinson’s disease detection and treatment. Nanobiosensors integrate science and engineering principles to detect Parkinson’s disease. The main advantages are their low cost, portability, and quick and precise analysis. Moreover, nanotechnology can transport medications in the form of nanoparticles across the blood–brain barrier. However, because nanobiosensors are a novel technology, their use in biological systems is limited. Nanobiosensors have the potential to disrupt cell metabolism and homeostasis, changing cellular molecular profiles and making it difficult to distinguish sensor-induced artifacts from fundamental biological phenomena. In the treatment of Parkinson’s disease, nanoparticles, on the other hand, produce neurotoxicity, which is a challenge in the treatment of Parkinson’s disease. Techniques must be developed to distinguish sensor-induced artifacts from fundamental biological phenomena and to reduce the neurotoxicity caused by nanoparticles.

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Publication

Investigation of Biosand Filter (BSF) on the Treatment Performance of Industrial Latex Wastewater

( 2024-01-01)

Najihah Abdul Rashid

;

Abdul Latif Abdul Rani

;

Mohd Firdaus Omar

;

Zainol N.A.

;

Salwa Mohd Zaini Makhtar

;

A B Wahab M.

;

Nabilah Aminah Lutpi

;

Farrah Aini Dahalan

Biosand Filters (BSF) has great potential to improve the water quality. BSF is used extensively in the treatment of drinking water in rural areas because it is affordable, simple to use, and has a high removal efficiency. This study used actual latex effluent to examine the effectiveness of SBR. The growth of the biolayer in the BSF is also observed. This study analyzes consistent and stable results for COD, DO and NH4-N+. With removal performance ranging from 87 % to 99 %. DO value for BSF varied from lowest value of 1.5 mg/L to 8mg/L. Overall, the BSF was capable of producing treated water for water reclamation.

Publication

Metasurface-based Frequency Reconfigurable two-port MIMO Antenna for 5G Application

( 2024-01-01)

Angadi S.

;

Sharma Y.

;

Nallanthighal Rghava S.

;

Thennarasan Sabapathy

In this work metasurface based frequency reconfigurable two-port multiple input multiple output (MIMO) antenna is presented. Initially, the proposed antenna is configured as a single-port radiating patch with pin-diode operating in the frequency reconfigurable mode. Later the designed antenna is converted to a two-port MIMO antenna that realizes an S11 below -10 dB intended for two resonant bands operating at 2.95 GHz (2.71-3.33 GHz) and 4.91 GHz (4.48-5.24 GHz) with pin-diode off-mode and 3.69 GHz (2.60-4.79 GHz) in on-mode with maximum peak realized gain of 6.29 dB and 4.13 dB at diode off-mode and 9.84 dB in diode on-mode. The two feeding ports of the proposed antenna are positioned adjacent to each other to permit the antenna in self-isolation mode later metasurface-reflector is placed below 10mm of radiator used as a de-coupling circuit and maintaining the minimum isolation of (S21) below -18.5 dB and maximum isolation of -23.07 dB in off-mode and -20.48 dB in diode on-mode. Moreover, the isolation and peak realized gain has improved after adding a reflector to the proposed antenna. The distance between antenna elements is 0.04 λo. The designed antenna is applicable for 5G new radio (NR) bands of n7, n48, n77, and n78 in on-mode, and n79 in diode off-mode respectively.

Publication

Isolation, screening and optimization of alkaliphilic cellulolytic fungi for production of cellulase

( 2024-01-01)

Zainuddin N.

;

Makhtar M.M.Z.

;

Gunny A.A.N.

;

Subash Chandra Bose Gopinath

;

Ahmad A.A.

;

Pusphanathan K.

;

Siddiqui M.R.

;

Alam M.

;

Rafatullah M.

This study concerns with the production and partial characterization of alkaline cellulase from alkaliphilic cellulolytic (AC) fungi isolated fromsoil in Perlis, Malaysia. The best fungi strain was selected on the basis of producing the highest cellulase at high pH conditions. Cellulase from the selected fungi strain was further characterized under saccharification but varies in operating parameters. Finally, the kinetic model describing the growth of the AC fungi strain was studied by employing the logistic model. Among the tested fungi strains, Basidiomycetes strain (BK1) showed high potentiality for the production of maximum alkaline cellulase production at pH 9 after 72 h of incubation at 30°C containing 6 g·L-1 carboxyl methyl cellulose. The saccharification process showed that the enzyme favour high alkaline condition and proves thermotolerant properties, while 15% (v/v) enzyme loading and 1% substrate concentration recorded the highest glucose production at about 1.2-1.3 mg·mL-1. The novelty of the study is to identify and optimize a unique indigenous fungi that emit alkaliphilic cellulase as alternative usage in biotechnology industries due to its capacity to adapt to the extreme conditions of specific industrial processes. There are revolutionary options for use in biotechnological businesses that involve high pH and therefore have substantial biotechnological promise.

Publication

Bio-removal of lead (II) ions under optimal condition by zinc chloride-impregnated activated carbon from brown alga

( 2024-01-01)

Osman N.S.

;

Ali U.F.M.

;

Subash Chandra Bose Gopinath

;

Hussin F.

;

Aroua M.K.

Sargassum sp., a brown alga in the division of macroalgae was evaluated for its ability to synthesis macroalgal-based activated carbon and remove lead (II) ions from synthetic aqueous solution. The sargassum activated carbon (SAC) was prepared by chemical activation impregnated with zinc chloride followed by carbonization. The surface morphology and functional group of untreated Sargassum sp. powder (SAP) and activated Sargassum sp. carbon (SAC) were scanned and presented with the Scanning Electron Microscope (SEM) and Fourier Transform Infrared spectroscopy (FTIR). Batch studies were conducted to explore maximum removal efficiency in term of pH, initial lead (II) ions concentration, contact time, adsorbent dosage, and temperature for the efficient adsorption. The maximum lead (II) ions uptake capacity for SAC was obtained at pH 5, initial lead (II) ions concentration at 25 mg/L, operation time of 60 min, adsorbent dosage of 0.1 g and temperature of 40 °C. The adsorption data were well-fitted by the Freundlich isotherm model, with an R2 value of 1.000, indicating a good fit. The kinetic study revealed that the adsorption of lead (II) ions followed a pseudo-first-order kinetic model, with an R2 value of 0.9746. This study validates the use of brown algae in the treatment of heavy metal contamination in wastewater.

Publication

EFFECT OF NITRATE ACID TREATED DOLOMITE ON THE TENSILE PROPERTIES OF ULTRA-HIGH MOLECULAR WEIGHT POLYETHYLENE (UHMWPE) COMPOSITES

( 2024-01-01)

Abdullah S.F.A.

;

Saleh S.S.M.

;

Nur Farahiyah Mohammad

;

Syarifah Nuraqmar Syed Mahamud

;

Mohd Firdaus Omar

;

Akil H.M.D.

;

Chang B.P.

;

Saliu H.R.

;

Rostam N.H.

;

Gondro J.

Ultra-High Molecular Weight Polyethylene (UHMWPE) polymers have been used in biomedical applications due to its biocompatibility, durability, toughness and high wear resistance. To enhance the mechanical properties, various types of minerals are commonly utilized as fillers in UHMWPE. One of the minerals is dolomite, which has been recognized as a valuable mineral with versatile applications, particularly in the field of biomedical applications. This paper presents the tensile properties of UHMWPE composites that filled with dolomite and treated-dolomite at various filler loading (i.e., 1-5 wt.%). Nitric acid and diammonium phosphate were used to treat the dolomite. From the results, the peaks of the FTIR spectrum displays carbonate (CO3–2), phosphate (PO4–3) and hydroxyl (OH–) groups in the ct-dolomite powder sample while the XRD pattern reveals that using dolomite treated with 1M nitric acid resulted in the presence of calcium hydroxide phosphate (Ca10(PO4)5(OH)) and MgO. For tensile strength, UHMWPE/ct-dolomite composites show better tensile strength than the pure UHMWPE composites. Treated improve the dolomite filler and resulted in significantly better matrix-filler interfacial interactions and improve the properties.

Publication

Oil palm waste-derived reduced graphene oxide (rGO) for dynamic adsorption of dye in a fixed-bed system

( 2024-01-01)

Mohd Ali Jinnah S.N.H.

;

Umi Fazara Md Ali

;

Subash Chandra Bose Gopinath

;

Naimah Ibrahim

;

Razi Ahmad

;

Mohamed Zuki F.

This study focuses on investigating the dynamic adsorption of Rhodamine B (RhB) from reduced graphene oxide (rGO) derived from oil palm waste. The synthesis of rGO from palm kernel shell (PKS) was achieved through double oxidation and carbonization method, resulting in a yield of 73.5 wt%. The reduction of oxygen-containing functionalities process using PKS was confirmed by FTIR spectroscopy, microscopic evaluation, and X-ray diffraction analyses. Laboratory-scale fixed-bed experiments were conducted with various process parameters. Both PKS and rGO were used as adsorbents, and a comparison was made based on breakthrough curve analysis, adsorption capacity and percentage removal of dye. The adsorption kinetics of RhB on PKS and rGO were best described by the non-linear Yoon-Nelson model, with a high adsorption capacity of 88.32 mg/g and 195.24 mg/g respectively. Using both PKS and rGO, the maximum adsorption capacity was observed when using 10 cm bed depth column, inlet dye concentration of 5 mg/L, flow rate of 12 mL/min and pH of 7. PKS exhibited good dye removal with an efficiency of 66.54%. Meanwhile, the exothermic behavior highlighted the potential of utilizing rGO for maximum dye removal, achieving an efficiency of 90.35%. This study justifies rGO as a cost-effective superior dye removal adsorbent, providing new prospect for large-scale dye removal.

Publication

Aquaculture monitoring system using multi-layer perceptron neural network and adaptive neuro fuzzy inference system

( 2024-01-01)

Abu Hassan Abdullah

;

Sukhairi Sudin

;

Saad F.S.A.

;

Muhamad Khairul Ali Hassan

;

Muhammad Imran Ahmad

;

bin Abdul Khalid K.A.

The water quality is the most important parameter for aquatic species health and growth. The condition is very critical and is essential to monitor continuously. Poor water quality will affect health, growth and ability of the animal to survive. These also affected their harvesting yields based on the amount and size of the animal. The main water parameters such dissolved oxygen (DO), pH, temperature, salinity and turbidity are monitored and control for good water quality. The data were acquired by the developed instrument and send wirelessly through GPRS/GSM module to cloud-based database. The data were retrieved and the water quality is predicted using fuzzy logic and multi-layer perceptron. MATLAB software was used for the model which is developed based on Mamdani fuzzy interface system. The membership functions of fuzzy were generated, as well as the simulation and analysis of the water quality system. Results show that the performance of fuzzy method can improve system performance in monitoring the water quality. This system also provides alert signals to farmers based on specific limit value for the water quality parameters. This will help the breeders to make certain adjustment to ensure suitable water quality for the aquaculture system.

Publication

FloodIntel: Advancing flood disaster forecasting through comprehensive intelligent system approach

( 2024-01-01)

Ayoub N.A.

;

Aziz A.A.

;

Wan Azani Wan Mustafa

Background: Every year, floods are the most devastating natural disaster that hits Malaysia, causing damage to people’s livelihoods, destroying property and infrastructure, and taking lives. Flood disasters are becoming more frequent and severe, necessitating the development of sophisticated forecasting and early warning systems to mitigate their effects. This study presents the design and implementation of a sophisticated flood forecasting and early warning system, utilizing intelligent technologies to enable timely prediction and proactive measures in high-risk areas. Methods: The proposed system incorporates Internet of Things (IoT) technology to collect real-time data on the river’s water level. The collected data are analyzed using an association rule technique to generate accurate forecasts of prospective flood occurrences. By using this intelligent flood disaster prediction system, users and authorities can receive early warnings and make informed decisions regarding evacuation, resource allocation, and infrastructure reinforcement. The system’s capability to provide early flood forecasts in high-risk areas can substantially enhance flood preparedness and response and save more life. Results: The findings of the study highlight the potential of the system to improve flood risk management strategies and reduce flood-related devastation and human suffering in vulnerable regions. Conclusions: In conclusion, it is important to implement IoT and AI technologies to improve flood prediction systems and reduce the negative effects of flood disasters.

Publication

Effect of varying core density and material on the quasi-static behaviors of sandwich structure with 3D-printed hexagonal honeycomb core

( 2024-01-01)

Ainin F.N.

;

Mohd Azaman Md Deros

;

Mohd Shukry Abdul Majid

;

Mohd Ridzuan Mohd Jamir

Additive manufacturing (AM) involves the development of complex, lightweight sandwich structures for the automotive and aerospace industries. These structures are essential for load bearing and impact resistance. Nevertheless, there is a significant obstacle of failure under compressive loading, e.g. through brittle fractures and crushing. To address this issue, this study evaluates the compressive properties, energy absorption and failure damage in quasi-static tests (flatwise, in-plane, and flexural) of sandwich composites with 3D-printed hexagonal honeycomb cores of different unit cells (6, 8 and 10 mm) and materials (polylactic acid (PLA), PLA-Carbon and PLA-Wood). The results show that increasing the core density enhances compressive strength, modulus, and energy absorption. An 8 mm unit cell absorbs energy optimally for lightweight structures. In PLA flatwise testing, the 8 mm unit cell absorbed 419.49 J more energy than the 10 mm unit cell. Additionally, PLA-Wood has better mechanical performance than PLA-Carbon due to the better filler with the PLA- matrix. In flatwise testing with an 8 mm unit, PLA-Wood absorbs 214.01 J, while PLA-Carbon absorbs 122.49 J. The failure modes vary depending on tests performed. The study highlights the potential of 3D-printed honeycomb core structures for load-bearing applications in various industries, including aerospace and automotive. Highlights: Quasi-static loading behavior of 3D-printed hexagonal honeycomb cores. Increased core density improves compressive stress, modulus, and absorbed energy. An optimal unit cell size for lightweight 3D printed core structures is 8 mm. PLA-Wood performs better in energy absorption due to filler compatibility. The failure modes are related to the type of quasi-static loads applied.

Publication

Predicting student final examination result using regression model based on student activities in learning management system

( 2024-01-01)

Pa N.N.N.

;

Aziz A.A.

;

Safei S.

;

Wan Azani Wan Mustafa

Background: Learning analytics (LA) is the measurement, collection, analysis, and reporting of data about learners and their contexts to understand and optimize learning and the environments in which it occurs. Most teaching and learning (T & L) data was obtained from learning management systems (LMS), such as Moodle platform. However, this data is not utilized for teaching purposes, for example, learning how students’ activities can influence the final exam marks. Methods: Therefore, this study aims to find a correlation and develop a prediction model between students’ activities, independent variables known as LMS factors, against dependence variables, which are students’ final results. Besides, four non-LMS factors (race, sponsorship, admission requirements and final coursework marks) were also included in the research to obtain the best model. The regression analysis, models are used to predict the outcomes by evaluating the accuracies of testing data. Results: The findings reveal that the best model utilizes Simple Linear Regression (SLR) with coursework as an independent variable, resulting in an average error difference (AED) of only 1.8. The remaining experiments produced AED results ranging from 2.74 to 7.58 using Multilinear Regression (MR). Conclusions: in summary, this study provides a significant finding that demonstrates the potential of utilizing LMS activities to predict final marks, enabling lecturers to enhance their students’ results.

Publication

SOSFloodFinder: A text-based priority classification system for enhanced decision-making in optimizing emergency flood response

( 2024-01-01)

Kamal S.H.

;

Aziz A.A.

;

Wan Azani Wan Mustafa

Flooding is a significant concern in nations with frequent precipitation because it can instantly affect multiple regions simultaneously. Due to the unpredictability of their occurrence caused by rapid water level rise, it is challenging to predict such natural disasters accurately. During flooding, prompt rescue efforts are crucial for the affected population. Due to flooded highways and residences, rescue teams may have difficulty locating victims. This hinders the potentially perilous and time-consuming rescue operation. To address this problem, we propose a web-based system that integrates natural language processing (NLP) with global positioning system (GPS) functionality. The SOSFloodFinder system provides automatic classification priorities for text messages sent by flood victims, as well as their most recent or current locations. The classification of text based on priority enables efficient resource allocation during rescue operations. In conclusion, this system has the potential to reduce future flood-related fatalities. Additional research and development are necessary to thoroughly investigate this method’s practical capabilities and effectiveness.

Publication

End-user perspectives on fintech services adoption in the Bangladesh insurance industry: the moderating role of trust

( 2024-01-01)

Hassan M.S.

;

Md. Aminul Islam

;

Abdullah A.B.M.

;

Nasir H.

This study focuses on understanding the factors that influence end-users’ (customers’) acceptance of fintech services in the insurance industry. The study employed a modified Unified Theory of Acceptance and Use of Technology 2 model, incorporating perceived security and personal innovativeness as independent variables, and trust as a moderating variable. A total of 391 responses were analyzed using partial least squares structural equation modeling in SmartPLS software. The study’s findings indicate that factors such as effort expectancy, social influence, facilitating conditions, perceived, and personal innovativeness positively affect users’ behavioral intention (BI) to use fintech services in the insurance industry. Moreover, BI positively influences the actual use (AU) of fintech services. Additionally, trust plays a positive moderating role between BI and AU. The results of this study have practical implications for academicians, researchers, insurance companies, and insurance regulatory bodies. Academicians and researchers can further explore the acceptance of fintech in developing countries based on these findings. Insurance companies and regulatory bodies can take necessary steps and formulate strategies to promote the adoption of fintech services in the insurance industry, considering the identified factors and the role of trust.

Publication

A Review on Graphene Analytical Sensors for Biomarker-based Detection of Cancer

( 2024-01-01)

Subash Chandra Bose Gopinath

;

Ramanathan S.

;

More M.

;

Patil K.

;

Patil S.J.

;

Patil N.

;

Mahajan M.

;

Madhavi V.

The engineering of nanoscale materials has broadened the scope of nanotech-nology in a restricted functional system. Today, significant priority is given to immediate health diagnosis and monitoring tools for point-of-care testing and patient care. Graphene, as a one-atom carbon compound, has the potential to detect cancer biomarkers and its derivatives. The atom-wide graphene layer specialises in physicochemical characteristics, such as improved electrical and thermal conductivity, optical transparency, and increased chemical and mechanical strength, thus making it the best material for cancer biomarker detection. The outstanding mechanical, electrical, electrochemical, and optical properties of two-dimensional graphene can fulfil the scientific goal of any biosensor development, which is to develop a more compact and portable point-of-care device for quick and early cancer diagnosis. The bio-functionalisation of recognised biomarkers can be improved by oxygenated graphene layers and their composites. The significance of graphene that gleans its missing data for its high expertise to be evaluated, including the variety in surface modification and analytical reports. This review provides critical insights into graphene to inspire research that would address the current and remaining hurdles in cancer diagnosis.

Publication

Delaying the Ripening of Banana Fruit and Increased Storage Shelf-Life Using Hydrophobic Deep Eutectic Oil (Menthol–Thymol)-In-Water Nanoemulsion Coating

( 2024-01-01)

Gidado M.J.

;

Ahmad Anas Nagoor Gunny

;

Sri Alamelu Sankari R.

;

Subash Chandra Bose Gopinath

;

Wongs-Aree C.

;

Shukor H.

;

Ibrahim R.

Hydrophobic deep eutectic oil (menthol-thymol)-in-water nanoemulsion was developed to preserve the quality of banana fruit and extend their storage shelf life. Storage preservation of bananas presents several challenges due to their high respiration rate, ethylene production, and susceptibility to various physiological and biochemical changes. The storage shelf life of bananas is relatively short compared to other fruits due to the combination of rapid ripening and sensitivity to ethylene and temperature. In this study, the effectiveness of HyDEN treatment was assessed on changes in banana fruit’s physiological parameters such as firmness, weight loss, total soluble solids, titratable acidity, and colour for 14 days storage time [25 °C ± 1 °C, 67% relative humidity (RH)]. HyDEN treatment preserved the physicochemical characteristics of banana fruit and was effective in delaying the ripening process. The storage shelf life of banana fruit treated with HyDEN increased for 14 days compared to control that ripened and physically damaged after 8 days of storage. This study provided a new delivery system for applying HyDEN as an edible coating to fruit after harvest preservation.

Publication

Self-Isolated Frequency Reconfigurable two-port MIMO Antenna for 5G Application

( 2024-01-01)

Angadi S.

;

Sharma Y.

;

Rghava S.N.

;

Thennarasan Sabapathy

In this work two-port multiple input multiple output (MIMO) antenna with self-isolation between antenna elements is presented. Initially, the proposed antenna is constructed as a single-port square-shaped radiating patch connected diagonally with a stub to operate the antenna in frequency reconfigurable mode. A 2×2 mm slot is cut at the middle part of the stub for implementing reconfigurability on the radiating patch to operate the antenna in multi-functional mode. Later the proposed antenna is converted to two-port frequency reconfigurable MIMO antenna that realizes an S11 below -10 dB intended for two resonant bands operating at 3.79 GHz (3.41-4.04 GHz) with pin-diode off-mode and 4.53 GHz (4.69-4.88 GHz) in on-mode with maximum peak realized gain of 4.93 dB at diode off-mode and 4.55 dB in pin diode on-mode. moreover, the gain is enhanced by 1.5 dB after converting to the two-port antenna. The two feeding ports of the proposed antenna are positioned orthogonal to each other to permit the antenna in self-isolation mode without connecting any de-coupling circuit and maintaining the mutual coupling (S21) below-21 dB in off-mode and -29.50 dB in diode on-mode. The distance between antenna elements is 0.12 λ0. In addition to that, two-port MIMO of envelope correlation coefficient (ECC), channel capacity loss (CCL), total active reflection coefficient (TARC), mean effective gain (MEG), and diversity gain (DG) are simulated. The designed antenna is applicable for 5G new radio (NR) bands of n48, n78 in off-mode, and n79 in on-mode respectively.

Publication

Physicochemical Properties of Industrial Wood Waste-Derived Cellulose Nanofibrils

( 2024-01-01)

Hing M.H.

;

Mohd Hanif Mohd Pisal

;

Sezali N.A.A.

;

Ong H.L.

;

Doong R.A.

Wood is an important raw material, especially for construction and industrial scale activities which have resulted in a large amount of wood waste (WW). The accumulation of industrial WW has led to serious environmental issues; hence, the utilization of the industrial WW is being studied by researchers due to the rich content of cellulose. This study investigated the physicochemical properties of cellulose nanofibrils (CNFs) derived from industrial WW. The preparation of the CNFs involves the pretreatment of WW with an alkaline deep eutectic solvent (DES) and bleaching with peracetic acid, followed by 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation and mechanical post-treatment. Interestingly, the yield of the CNFs produced was 52%, which is half of the raw material used. Furthermore, the morphology of the WW-derived CNFs was analyzed from scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The WW-derived CNFs showed a uniform size with a width of around 20–100 nm and a length of several micrometers. Moreover, the production of WW-derived CNFs was further verified by Fourier transform infrared spectroscopy (FTIR) for the surface functional groups, X-ray diffraction (XRD) for the crystallography, and thermal gravimetry analysis (TGA) for thermal stability. The results obtained from these characterization methods have proved the successful transformation of the industrial WW into a high-potential nanomaterial, which is the CNFs that can be used for further applications in paper making, composites, packaging, textiles, biomedicine, energy storage, and electronics.

Publication

Thermal behaviour of graphene nanoplatelets and multiwalled carbon nanotubes filled-glass fibre-reinforced epoxy composites

( 2024-01-01)

Ahmad M.A.A.

;

Mohd Ridzuan Mohd Jamir

;

Mohd Shukry Abdul Majid

;

Sapuan S.M.

;

Ismail M.S.

;

Zuradzman Mohamad Razlan

;

Shahriman Abu Bakar

The effects of thermal behaviour on graphene nanoplatelets (GP) and multiwalled carbon nanotube (CN) nanofillers of glass fibre (GL)-reinforced epoxy composites were investigated. The paper aims at evaluating, through a single and hybrid carbon-based nanofiller on the thermal stability, mechanical properties, electromechanical properties at elevated temperature, and morphologies of the composites. The nanofillers were dispersed using a mechanical stirrer, Thinky mixer, and ultrasonic probe. Hand lay-up and vacuum bagging techniques were used in the manufacturing of composites. Real-time self-monitoring of the structural damage to the specimens under tensile and flexural tests was performed through electromechanical measurements. Using the GP–CN hybrid in the composite improved the adhesion between the hybrid nanofillers and matrix. The thermal properties of GP–GL, CN–GL, and GP–CN–GL hybrid composites increased with the hybrid nanofiller addition. Mechanical testing at elevated temperatures revealed a higher rate of strength degradation for the 1.5-mass% GP–CN–GL hybrid composite than for a single nanofiller composite. The GP–CN–GL hybrid composites exhibited a more pronounced nonlinear behaviour and lower resistance.

Publication

Computational Fluid Dynamics Analysis of Varied Cross-Sectional Areas in Sleep Apnea Individuals across Diverse Situations

( 2024-01-01)

Faizal W.M.

;

Khor Chu Yee

;

Mohamad Suhaimi Shahrin

;

Mohd. Hazwan Mohd. Hanid

;

Masniezam Ahmad

;

Misbah M.N.

;

Haidiezul A.H.M.

Obstructive sleep apnea (OSA) is a common medical condition that impacts a significant portion of the population. To better understand this condition, research has been conducted on inhaling and exhaling breathing airflow parameters in patients with obstructive sleep apnea. A steady-state Reynolds-averaged Navier–Stokes (RANS) approach and an SST turbulence model have been utilized to simulate the upper airway airflow. A 3D airway model has been created using advanced software such as the Materialize Interactive Medical Image Control System (MIMICS) and ANSYS. The aim of the research was to fill this gap by conducting a detailed computational fluid dynamics (CFD) analysis to investigate the influence of cross-sectional areas on airflow characteristics during inhale and exhale breathing in OSA patients. The lack of detailed understanding of how the cross-sectional area of the airways affects OSA patients and the airflow dynamics in the upper airway is the primary problem addressed by this research. The simulations revealed that the cross-sectional area of the airway has a notable impact on velocity, Reynolds number, and turbulent kinetic energy (TKE). TKE, which measures turbulence flow in different breathing scenarios among patients, could potentially be utilized to assess the severity of obstructive sleep apnea (OSA). This research found a vital correlation between maximum pharyngeal turbulent kinetic energy (TKE) and cross-sectional areas in OSA patients, with a variance of 29.47%. Reduced cross-sectional area may result in a significant TKE rise of roughly 10.28% during inspiration and 10.18% during expiration.

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