Faculty of Electronic Engineering & Technology
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MY
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Pauh Putra, Perlis

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Now showing 1 - 10 of 48
  • Publication
    Remazol orange dye sensitized solar cell
    ( 2017-01-03)
    Siti Salwa Mat Isa
    ;
    Muhammad Mahyiddin Ramli
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Muda M.R.
    ;
    Shahrir Rizal Kasjoo
    ;
    Muammar Mohamad Isa
    ;
    Nurul Izza Mohd Nor
    ;
    Norhawati Ahmad
    ;
    Nazuhusna Khalid
    ;
    Nur M. Selamat
    ;
    Nur Asyikin Mohd Anhar
    Water based Remazol Orange was utilized as the dye sensitizer for dye sensitized solar cell. The annealing temperature of TiO2 working electrode was set at 450 °C. The performance of the device was investigated between dye concentrations of 0.25 mM and 2.5 mM at three different immersion times (3, 12 and 24 hours). The adsorption peak of the dye sensitizer was evaluated using UV-Vis-Nir and the device performance was tested using solar cell simulator. The results show that the performance was increased at higher dye concentration and longer immersion time. The best device performance was obtained at 0.2% for dye concentration of 2.5 mM immersed at 24 hours.
  • Publication
    Effect of sodium ion addition on copper selenide/chitosan film towards electrical and shielding efficiency improvement
    ( 2024-06)
    Nurul Najiha Mazu
    ;
    Hazeem Ikhwan Mazlan
    ;
    Josephine Ying Chyi Liew
    ;
    Nurul Huda Osman
    ;
    Muhammad Mahyiddin Ramli
    ;
    Ali Reshak
    The operation of electronic devices can be disrupted by unwanted electromagnetic signals, affecting its operation. Deploying electromagnetic shielding is a viable solution to minimize the impact of electromagnetic interference (EMI). The conventional methods of electromagnetic shielding use metal gaskets to safeguard sensitive electronic components, which have drawbacks of cost and weight. Hence, electromagnetic shielding polymer can be an alternative to replace metal gaskets. This work investigates the effect of sodium ion (Na) addition to copper selenide/chitosan (CuSe/Ch) film for electromagnetic shielding applications. The shielding polymers were produced using solution casting methods, while the CuSe was synthesized using the chemical coprecipitation method. Impedance spectroscopy and two port waveguide methods were used to characterize the prepared polymer's electrical properties and shielding efficiency. The results indicate that Na incorporation in the CuSe/Ch film resulted in a 47 % decrease in bulk resistivity and increased DC conductivity from 6.07 × 10-6 S/cm to 3.69 × 10˗5 S/cm. The AC conductivity of films containing Na demonstrates a similar level of conductivity at lower frequencies, followed by a sharp increase at higher frequencies, indicating a more substantial influence of Na at higher frequencies. Higher absorption shielding efficiency (SEA) and lower reflection shielding efficiency (SER) were achieved by introducing Na into the CuSe chitosan film. The Na/CuSe/Ch film shows higher total shielding efficiency at an average of 20 dB, equivalent to 99 % of the EM power shield.
  • Publication
    Single wall carbon nanotubes dispersion study of different dye molecules and chitosan
    ( 2017-09-26)
    Muhammad Mahyiddin Ramli
    ;
    Siti Salwa Mat Isa
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Sohiful Anuar Zainol Murad
    Carbon Nanotubes (CNTs) is known for their hydrophobicity ability. However, this ability can become the bottleneck for the application of CNTs where a highly dispersion of materials are needed. In this project, different dispersing agents were investigated namely dye molecules and chitosan. Three different dyes are studied with different concentration, including 0.05 % of chitosan. The dispersion quality is determined by examining through UV-Vis-NIR. The best dispersion quality investigated here is when the concentration of dye molecules is higher, which is around 2.5 mM.
  • Publication
    Effect of soaking time towards graphitization of empty fruit bunch (EFB) waste
    (AIP Publishing, 2023)
    Norizah Abd Karim
    ;
    Che Mohd Ruzaidi Ghazali
    ;
    Muhammad Mahyiddin Ramli
    ;
    Marniati
    ;
    Zulfadhli, M. R.M.
    ;
    Mutiawati
    Empty fruit bunch (EFB) are the second-highest waste produced in the oil palm industry which is 18 022 tonnes in a year. However, the presence of oil palm waste especially from empty fruit bunch (EFB) give a major problem to the disposal. Herein, EFB waste has been identified as a potential carbon source for synthetic graphite production. This is due to implement the lower heating temperature of synthetic graphite produced in controlled heating conditions. Several parameters have been manipulated to study the effect of various parameters on the graphitization process. Hence, in this study, the effect of soaking time towards graphitization of empty fruit bunch (EFB) waste has been investigated. EFB waste was heat treated with various soaking times which is 2 hours, 2.5 hours and 3 hours in controlled heating conditions with constant heating temperature at 500°C and heating rate at 10°/minute After heating treatment, the samples were characterized using X-ray Diffraction (XRD) and analyzed by X'Pert Highscore Plus software. The functional group of synthetic graphite was determined by using Fourier Transform Infrared spectroscopy (FTIR). The morphological study was carried out by using Scanning Electron Microscope (SEM). From the analysis, the best synthetic graphite produced is at the 2.5 hours soaking time with a constant heating temperature at 500°C and a constant heating rate at 10°/min.
  • Publication
    Characterization of doped ZnO thin film for Ammonia gas sensing application
    (Institute of Physics, Polish Academy of Sciences, 2023)
    Shazlina Johari
    ;
    Fatin Amira Hasbullah
    ;
    Anis Syafiqa Rosman
    ;
    Muhammad Mahyiddin Ramli
    ;
    Mohd Fairus Ahmad
    ;
    Norizah Abd Karim
    ;
    Nurul Huda Osman
    ;
    D. Darminto
    ;
    Ali Hussain Reshak
    ;
    Sebastian Garus
    This paper reports on the characterization of Sn- and Al-doped zinc oxide thin film for potential ammonia gas detection. The sol–gel method has been used to deposit the dopant onto the glass substrate at an annealing temperature of 500◦C for three different doping concentrations, which are 0.5, 1.0, and 1.5 at.%. The method used to produce this thin film is sol–gel, as it is cheap, easy, and can be employed at low temperatures. The studies involve the investigation of the morphological structures and electrical and optical properties of doped ZnO. In terms of structural properties, scanning electron microscope images of Sn- and Al-doped ZnO change as the dopant concentration is increased. The doped thin film response and recovery towards 200 ppm of ammonia were observed and recorded. Both dopants show good gas sensing response. The recorded resistance reading suggests that Al is the superior dopant in gas sensing as it produces a low resistance reading of 230 Ω as opposed to 140 kΩ produced by Sn-doped ZnO thin film.
  • Publication
    Semiconducting biomass-based amorphous carbon films and their potential application in photovoltaic devices
    (Elsevier Ltd, 2025)
    Endhah Purwandari
    ;
    Retno Asih
    ;
    Sudarsono
    ;
    Diky Anggoro
    ;
    Gerald Ensang Timuda
    ;
    Malik Anjelh Baqiya
    ;
    Iman Santoso
    ;
    Hideki Nakajima
    ;
    Muhammad Mahyiddin Ramli
    ;
    Agus Subekti
    ;
    Darminto
    Amorphous carbon (aC) is highly appealing because of its unique structure, electrical and optical properties, making it appropriate for various applications, especially in energy conversion. This work presents a comprehensive study on the synthesis of aC materials, including both intrinsic (i-type) and doped conditions (p- and n-type), to enhance the performance of photovoltaic films. Carbon materials are derived from biomass using a straightforward and environmentally conscious technique. The obtained carbon compound demonstrates an amorphous state with a substantial prevalence of the sp2 C=C component. Raman spectroscopy and electron microscopy confirmed the stacking of 2D layers forming a multilayer graphene structure. The carbon compound prepared AC films deposited onto a quartz glass surface via spray coating. The films have a thickness ranging from 247 to 478 nm. The dielectric constants of the optical parameters reveal resonant exciton features at a photon energy of ∼3.8 eV, whereas the real component exhibits semiconductive properties. The refractive indices of the p-, i-, and n-layers, which have gap energies in decreasing order, demonstrate a decline. The optical conductivity of aC is higher than that of amorphous silicon, specifically 0.54 × 103Ω−1cm−1, 0.48 × 103 Ω−1cm−1, and 0.53 × 103 Ω−1cm−1 for the p-, i-, and n-type films, respectively. Based on this outcome, it is reasonable to suggest that the recently developed material is potentially important as a photovoltaic device.
  • Publication
    Binding dynamics and conformational stability of graphene-based nanomaterials with Mutant LOX-1: Insights from molecular docking and dynamics simulations in atherosclerosis
    (Springer, 2024-12)
    Farizah Hanim Lat
    ;
    Ahmad Naqib Shuid
    ;
    Mohd Yusmaidie Aziz
    ;
    Muhammad Mahyiddin Ramli
    ;
    Rafeezul Mohamed
    Oxidized low-density lipoprotein (oxLDL) is a critical factor in endothelial dysfunction and serves as an important biomarker for oxidative stress. Recent research has focused on lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), a receptor for oxLDL that plays a significant role in atherosclerosis progression. Mutant LOX-1 may show changes in its binding affinity for oxLDL, potentially leading to variations in oxLDL uptake and foam cell formation. Our previous investigation into graphene-based nanomaterials and their interactions with atherosclerosis-related proteins, including LOX-1, provided important insights into their binding characteristics. In this study, we delve deeper into the binding dynamics between graphene-based nanomaterials and mutant LOX-1, aiming to clarify their implications for atherosclerotic development. Using molecular docking techniques with AutodockVina and active site predictions from P2Rank, we evaluated the binding affinities of graphene, graphene oxide (GO), and reduced graphene oxide (rGO) to mutant LOX-1. Notably, all docking scores were below -5 kcal/mol, indicating strong interactions with the receptor. To investigate the dynamics of these interactions further, we performed molecular dynamics (MD) simulations using the CHARMM force field. Our simulations revealed significant conformational changes within the first 100 ns, particularly in the mutant LOX-1 and GO complex, which suggested improved binding stability. These results enhance our understanding of how graphene-based nanomaterials interact with mutant forms of LOX-1, offering potential avenues for targeted therapies in atherosclerosis management related to LOX-1 dysregulation.
  • Publication
    Revolutionizing cancer treatment by boosting dendritic cell vaccine efficacy with graphene oxide
    (EnPress Publisher LLC, 2023)
    Rafeezul Mohamed
    ;
    Muhammad Mahyiddin Ramli
    ;
    Ali H Reshak
    ;
    Nurul Huda Osman
    ;
    Mohd Yusmaidie Aziz
    ;
    Mohd Syahir Mansor
    Dendritic cells (DCs) are potent antigen presenting cells that play a crucial role in stimulating T cell responses against cancer. DC vaccines have been utilized as an immunotherapy approach for cancer treatment, but their effectiveness is hampered by challenges in the tumor microenvironment. Graphene oxide (GO), a cutting-edge carbon-based nanomaterial, has shown promise in modulating DC activation and function. This review highlights the recent advancements in DC vaccines and explores how GO can enhance their efficacy for cancer treatment. By leveraging the unique properties of GO, such as its biocompatibility and immunomodulatory effects, DC vaccines can potentially be optimized to overcome the limitations of the tumor microenvironment and achieve improved outcomes in cancer immunotherapy.
      2  6
  • Publication
    rGO-SWCNT hybrid for counter electrode in dye sensitized solar cell
    (Universiti Malaysia Perlis (UniMAP), 2018-12)
    M. R. Muda
    ;
    Siti S. Mat Isa
    ;
    Muhammad Mahyiddin Ramli
    Towards platinum free counter electrode in dye sensitized solar cells, some carbon-based materials like carbon nanotubes and graphene are fully utilized due to their extraordinary properties such as high aspect ratio and conductivity. In this paper, single-walled carbon nanotubes (SWCNT), reduced graphene oxide (rGO) and hybrid structure of rGO-SWCNT spray coated counter electrodes were compared with graphite as the reference material. The morphology of these materials was analyzed with FESEM and FTIR. The DSSC performance was then measured using solar simulator. The current-voltage (I-V) characteristics show that the rGO-SWCNT counter electrode result the excellent performance with efficiency of ~1.86 %, 95.2 % better than graphite. This higher performance was attributed by the complete oxygen-functional group removal during reduction process which offers large active surface area for electro-photocatalytic activity, higher conductivity, better structure and properties compared to the individual forms.
      1  16
  • Publication
    Automated monitoring system for transmission system laboratory model
    (Universiti Malaysia Perlis (UniMAP), 2018-12)
    MN Mohtar
    ;
    MA Osman
    ;
    Muhammad Mahyiddin Ramli
    Transmission System Laboratory Model (TSLM) is a model of power transmission systems use to facilitate the studies of power system. TSLM replicates a power transmission system mimicking the real transmission line. The input and output voltage reading on the current TSLM requires a manual measurement using multimeter. The lack of real time monitoring is rectified in this work. This works propose an automated real time measurement and display system for real time voltage input and output monitoring on the TSLM. An imbedded custom made digital voltmeter and a digital display is used for real time monitoring.
      11  2