SDI UMT 2025

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http://umt-ir2.umt.edu.my:4000/handle/123456789/21385

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Browsing SDI UMT 2025 by Author "PSNZ"

Now showing 1 - 11 of 11
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    COMPARATIVE ANALYSIS OF WASTE COOKING OIL BIODIESEL MIXED WITH NANOPARTICLE ADDITIVES ON PHYSICOCHEMICAL PROPERTIES AND DIESEL ENGINE PERFORMANCE
    (UNIVERSITI MALAYSIA TERENGGANU, 2025-09) PSNZ
    The hazardous effect of the pollution of fossil fuels has brought the necessity of shifting conventional energy sources to renewable and clean ones. In this study, the effect of hydrogen addition and CeO2 nanoparticle addition in waste cooking palm biodiesel on a CRDI engine is evaluated. The dosage of the nanoparticle is fixed at 75 ppm and a hydrogen flow rate of 10 L/min is selected for the engine operations. The crystalline structure of the nanoparticles is determined by XRD analysis. Results showed that on the addition of both H2 and CeO2 in a B20 biodiesel blend (80% diesel and 20% biodiesel) the performance, emission, and combustion parameters of the diesel engine improved compared to neat diesel. The brake thermal efficiency was improved by 3.53% and brake fuel consumption was reduced by 16.12% in comparison to diesel at 90% loading condition. The addition of both nanoparticles and hydrogen in the biodiesel blend lowered the emissions of CO by 30%, and HC and smoke by 50% and 42% respectively. However, NOx increased by 11% as compared to diesel. A 6% higher HRR values and 8% higher in-cylinder pressure were obtained while using hydrogen and CeO2 nanoparticle blended biodiesel. This blend also shows the lowest ignition delay period at full load condition which results in more engine power and efficiency. This experimental study has helped pave the way for the use of hydrogen-enriched and nanoparticle-blended biodiesel in place of fossil fuel for the applications of diesel engines.
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    ELUCIDATING THE CALCIUM OXIDE DERIVED FROM THE WASTE SHELLS OF MUD CLAM (GELOINA EXPANSA) AS A CATALYST FOR BIODIESEL PRODUCTION ELUCIDATING THE CALCIUM OXIDE DERIVED FROM THE WASTE SHELLS OF MUD CLAM (GELOINA EXPANSA) AS A CATALYST FOR BIODIESEL PRODUCTION
    (UNIVERSITI MALAYSIA TERENGGANU, 2025-10) PSNZ
    Biodiesel is one of the alternative forms of diesel fuel and can be obtained using the transesterification process of waste cooking oil with a catalyst to accelerate the reaction. The heterogeneous catalyst from waste scallop shells is used due to its potential for being reused in the subsequent transesterification reactions. Heterogeneous catalysts can also be recycled, contributing to their environmentally friendly nature. This study aims to identify the performance of recycling a calcium oxide (CaO) catalyst from scallop shell waste on synthesis biodiesel. The method used is the transesterification method with the basic ingredients of waste cooking oil using a CaO catalyst. Then, after the transesterification process is complete, the catalyst is separated from the biodiesel and recycled to be reused in the transesterification process up to five times. The biodiesel samples obtained are identified for yield value, physico-chemical properties, thermal properties and performance. X-ray diffraction characterization results for the CaO catalyst show that it has a crystal size of 67.83 nm. Scanning electron microscope characterization shows that it has spherical particle shapes. Fourier transform infrared characterization shows the presence of Ca–O bonds. The highest biodiesel yield value of 74.23% is obtained in biodiesel Cycle 1. The flash point value of biodiesel samples ranges from 141.2°C to 149°C. Further, all of the biodiesel samples exhibit a cetane number of 75. The highest lower heating value of 38.22 MJ/kg is obtained in biodiesel Cycle 1 and the viscosity of the biodiesel samples ranges from 5.65 to 5.88 cSt. The density of the biodiesel samples ranges from 881.23 to 882.92 kg/m3. Besides, ester functional groups (C=O) and methyl functional groups have been successfully formed in all samples, with the methyl oleate compound observed as dominating the biodiesel samples. The cloud point value of the biodiesel samples ranges from 12°C to 13°C, and their pour point value ranges from 10°C to 12°C. The lead content in biodiesel is 0.8826 mg/kg. The lowest sulphur content is obtained from biodiesel Cycles 1 and 2 at 0.005%. Performance tests show that biodiesel has lower torque and brake power values than commercial diesel fuel and higher specific fuel consumption values than commercial diesel fuel.
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    ELUCIDATION OF ANTIBIOFILM FORMATION MECHANISMS USING MARINE EXTRACTS AGAINST INFECTION AND ANTIMICROBIAL RESISTANCE (AMR) ELUCIDATION OF ANTIBIOFILM FORMATION MECHANISMS USING MARINE EXTRACTS AGAINST INFECTION AND ANTIMICROBIAL
    (UNIVERSITI MALAYSIA TERENGGANU, 2025-11-24) PSNZ
    Antimicrobial resistance (AMR) has emerged as a global health crisis, with methicillinresistant Staphylococcus aureus (MRSA) representing one of the most clinically significant multidrug-resistant pathogens. In this study, three structurally unique anthracycline derivatives—keto-ester (1), 4-deoxy-ε-pyrromycinone (2), and misamycin (3)—were first isolated and characterized from the fermentation broth of the marine-derived Streptomyces tauricus NBUD24. These compounds exhibited notable antibacterial efficacy against MRSA, with minimum inhibitory concentrations (MICs) ranging from 16 to 32 μg/mL. Cytotoxicity assays confirmed their safety profile at therapeutic concentrations. The biofilm formation assay demonstrated that 4-deoxy-ε-pyrromycinone inhibited biofilm formation of MRSA ATCC43300, with an inhibition rate of 64.4%. Investigations of antibacterial mechanisms revealed that these compounds exert antibacterial effects primarily through disruption of bacterial cell wall integrity and destruction of DNA structure. These findings underscore the potential of marine-derived microbial metabolites as promising scaffolds for developing next-generation antimicrobial candidates to combat drug-resistant infections.
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    INFLUENCE OF ANTHROPOGENIC POLLUTANTS ON MUD CRAB ECOSYSTEMS TO ENSURE SUSTAINABLE AQUACULTURE AND SAFE CONSUMPTION TO HUMAN HEALTH
    (UNIVERSITI MALAYSIA TERENGGANU, 2025-04) PSNZ
    Heavy metal pollution from anthropogenic activities can harm aquatic ecosystems. This study aims to determine the concentration of heavy metals (Pb and Cu) in waters, sediments, and mud crabs (Scylla serrata), and to analyze the relationship between environmental parameters and S. serrata which is consumed by humans. Samples were taken in the mangrove ecosystem around the Tanjung Api-Api port area in South Sumatra, Indonesia. Pb and Cu analysis used the Atomic Absorption Spectrophotometer (AAS). Pb and Cu linkages in waters, sediments, and S. serrata analyzed by SigmaPlot V12.5 and Principal Component Analysis (PCA) analyzed by XLSTAT 2022. The limit consumption of S. serrata was calculated using MWI (MaximumWeekly Intake) and MIT (Maximum Intake Tolerance). Based on the results, the heavy metal Pb in water was 0.1055 – 0.1322 mg.L−1, and Cu was not detected. Furthermore, Pb in sediments ranged from 7.0104 - 11.8186 mg.kg−1, Cu 3.7127 - 4.5347 mg.kg−1, and Pb in S. serrata ranged from 0.0001 - 0.0021 mg.kg−1, and Cu ranged from 0.03 – 0.0791 mg.kg−1. The concentration of heavy metals in water, sediment, and S. serrata had not exceeded the specified quality standard, except for Pb in water. The principal component analysis obtained F1 (44.35%), F2 (27.53%) and F3 (17.83%) groups. Based on MWI and MIT values that S. serrata was still safe for human consumption.
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    INVESTIGATING THE ROLE OF GIBBERELLIC ACID (GA) AND ABSCISIC ACID (ABA) CROSS-TALK IN ENHANCING TUBEROUS ROOT DEVELOPMENT IN SWEET POTATOES
    (Society for Experimental Biology and John Wiley & Sons Ltd, 2025) PSNZ
    Sugar Will Eventually be Exported Transporter (SWEET) proteins are key transporters in sugar transportation. They are involved in the regulation of plant growth and development, hormone crosstalk, and biotic and abiotic stress responses. However, SWEET family genes have not been explored in the sweet potato. In this study, we identifie 27, 27, and 25 SWEETs in cultivated hexaploid sweet potato (Ipomoea batatas, 2n = 6x = 90) and its two diploid relatives, Ipomoea trifid (2n = 2x = 30) and Ipomoea triloba (2n = 2x = 30), respectively. These SWEETs were divided into four subgroups according to their phylogenetic relationships with Arabidopsis. The protein physiological properties, chromosome localization, phylogenetic relationships, gene structures, promoter cis-elements, protein interaction networks, and expression patterns of these 79 SWEETs were systematically investigated. The results suggested that homologous SWEETs are differentiated in sweet potato and its two diploid relatives and play various vital roles in plant growth, tuberous root development, carotenoid accumulation, hormone crosstalk, and abiotic stress response. This work provides a comprehensive comparison and furthers our understanding of the SWEET genes in the sweet potato and its two diploid relatives, thereby supplying a theoretical foundation for their functional study and further facilitating the molecular breeding of sweet potato.
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    MULTI-OBJECTIVE OPTIMIZATION ALGORITHM FOR AUTONOMOUS SPATIAL LAYOUT DESIGN
    (UNIVERSITI MALAYSIA TERENGGANU, 2025-07) PSNZ
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    A NEW DIGITAL TRANSFORMATION FRAMEWORK TO ENHANCE ESG PERFORMANCE FOR PUBLIC LISTED COMPANIES IN MALAYSIA
    (PSNZ, 2025) PSNZ
    This paper aims to explore whether the trend of digital transformation is driving companies to engage in environmental, social, and governance (ESG) practices. The impact of strategic transformation on firms is all-encompassing, making it difficult to capture the mechanisms of impact on corporate ESG practices. To this end, we con- struct a new theoretical framework that combines slack resources and stakeholder theory. This framework attributes the heterogeneity of ESG practices to differences in the ability and willingness of companies. Using data from Chinese listed companies, we find that the digital transformation is improving ESG performance.
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