Mohd Ridzuan Mohd Jamir
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Preferred name
Mohd Ridzuan Mohd Jamir
Official Name
Mohd Ridzuan , Mohd Jamir
Alternative Name
Ridzuan Mohd Jamir, Mohd
M Ridzuan, M. J.
Ridzuan, M. J.M.
Mohd Jamir, Mohd Ridzuan
Jamir, Mohd Ridzuan Mohd
Main Affiliation
Scopus Author ID
36069815000
Researcher ID
H-9343-2012

Research Output

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  • Publication
    Regression analysis of the dielectric and morphological properties for porous Nanohydroxyapatite/Starch composites: a correlative study
    ( 2022)
    Chong You Beh
    ;
    Cheng Ee Meng
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Mohd Shukry Abdul Majid
    ;
    Khor Shing Fhan
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Emma Ziezie Mohd Tarmizi
    ;
    Kim Yee Lee
    This paper aims to investigate the dielectric properties, i.e., dielectric constant (ε′), dielectric loss factor (ε″), dielectric tangent loss (tan δ), electrical conductivity (σ), and penetration depth (Dp), of the porous nanohydroxyapatite/starch composites in the function of starch proportion, pore size, and porosity over a broad band frequency range of 5 MHz–12 GHz. The porous nanohydroxyapatite/starch composites were fabricated using different starch proportions ranging from 30 to 90 wt%. The results reveal that the dielectric properties and the microstructural features of the porous nanohydroxyapatite/starch composites can be enhanced by the increment in the starch proportion. Nevertheless, the composite with 80 wt% of starch proportion exhibit low dielectric properties (ε′, ε″, tan δ, and σ) and a high penetration depth because of its highly interconnected porous microstructures. The dielectric properties of the porous nanohydroxyapatite/starch composites are highly dependent on starch proportion, average pore size, and porosity. The regression models are developed to express the dielectric properties of the porous nanohydroxyapatite/starch composites (R2 > 0.96) in the function of starch proportion, pore size, and porosity from 1 to 11 GHz. This dielectric study can facilitate the assessment of bone scaffold design in bone tissue engineering applications.
  • Publication
    Physical, thermal, and mechanical properties of highly porous polylactic acid/cellulose nanofibre scaffolds prepared by salt leaching technique
    ( 2021)
    Revati Radakisnin
    ;
    Mohd Shukry Abdul Majid
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Mohd Faizal Mat Tahir
    ;
    Cheng Ee Meng
    ;
    Hassan Al Alshahrani
    This study aimed to prepare and characterise polylactic acid (PLA) reinforced with cellulose nanofibre (CNF) from a Pennisetum purpureum-based composite scaffold and determine its structural and mechanical properties. Porous scaffolds with CNF compositions of 5‒20 wt% in the PLA matrix were developed using solvent casting and particulate leaching of its porogen at 90 wt% of loadings. Morphology studies using field emission scanning electron microscopy revealed that the scaffolds had well-interconnected pores with an average pore size range of 67‒137 µm and porosity >76%. X-ray diffraction confirmed the interconnectivity and homogeneity of the pores and the fibrous structure of the scaffolds. The compressive strength of the fabricated scaffolds varied between 2.34 and 6.66 MPa, while their compressive modulus was between 1.95 and 6.04 MPa for various CNF contents. Furthermore, water absorption and thermal degradation studies showed that the scaffold had good hydrophilicity and improved thermal stability. These findings highlight the need to modify the pore structure and mechanical performance simultaneously for tissue engineering. Thus, this study concludes that the developed PLA scaffolds reinforced with CNF from Pennisetum purpureum are potential candidates for cell attachment and extracellular matrix generation.
  • Publication
    Fourier transform infrared spectroscopy of graphene nanoplatelets-glass and multi-walled carbon nanotubes-glass reinforced epoxy composite
    ( 2024-03-07)
    Ahmad M.A.A.
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Mohd Shukry Abdul Majid
    ;
    Cheng Ee Meng
    ;
    Mohd Shihabudin Ismail
    This study investigates the effect of nanofiller loading of graphene nanoplatelets and multi-walled carbon nanotubes on the characterisation of glass reinforced epoxy composite. The GNP-glass and MWCNT-glass composites were prepared using the hand lay-up and vacuum bagging method. The nanofiller weight fraction at 0.5, 1.5, 3, and 5 wt. % was being analysed. FTIR spectra were used to evaluate the GNP and MWCNT nanofiller's contribution to different crystalline formations in the epoxy matrix. The result indicates a variation peak in GNP-glass and MWCNT-glass reinforced epoxy composites due to nanofiller incorporation. The stretching vibration peak in the transmittance percentage was related to the better bond formation of the nanofiller with the epoxy matrix.
  • Publication
    The Effect of the Amylose/Amylopectin Contents of Starch on Porosity and Dielectric Properties of the Porous Hydroxyapatite/Starch Composites
    ( 2020-07-09)
    Chong You B.
    ;
    Cheng Ee Meng
    ;
    Abu Bakar S.
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Eng Swee Kheng
    ;
    Mohd Shukry Abdul Majid
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Khor Shing Fhan
    This study aims to determine the effect of the amylose/amylopectin contents of starch on the porosity and dielectric properties of porous hydroxyapatite/starch composites. The porous hydroxyapatite/starch composites were prepared by utilizing the starches (rice, corn and potato starch) via gelatinization and retrogradation process. The complex permittivity of the porous hydroxyapatite/starch composites were evaluated in the frequency range of 12.4-18.0 GHz. The porous composites were exhibited the higher average porosity by using the starch with higher amylopectin content. The highly porous hydroxyapatite/starch composites with higher amylopectin content show the significant fluctuation peaks (at 13.8 and 16.6 GHz) and the higher imaginary part of the complex permittivity (ϵ′′) at higher frequency in the dielectric spectrum, respectively. The real (ϵ′) and imaginary part (ϵ′′) of the complex permittivity of the porous composites could be enhanced by increasing the average porosity and the amylopectin contents.
  • Publication
    Microwave dielectric analysis on adhesive disbond in acrylic glass (Poly (Methyl Methacrylate)) at KU-band
    ( 2020-10-01)
    Cheng Ee Meng
    ;
    Mohd A.R.
    ;
    Shahriman Abu Bakar
    ;
    Zuradzman Mohamad Razlan
    ;
    You K.Y.
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Mohd Shukry Abdul Majid
    ;
    Khairul S.B.
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Beh C.Y.
    ;
    Khor Shing Fhan
    A microwave dielectric spectroscopy for detecting adhesive disbonds between acrylic glass (aka Poly (methyl methacrylate)) was discussed. The adhesive bond was developed using epoxy resin and acrylate. The level of joint disbond can be quantified using Young Modulus. In this work, the strength of bond is affected by radius of air void within adhesive bond. A high-frequency electromagnetic wave propagated through two joint acrylic glass with acrylate and epoxy adhesive using waveguide adaptor WR90 in conjunction with professional network analyser. This electromagnetic wave is reflected and transmitted at the bond interface due to mismatch impedance at adhesive bond. The output is a dielectric properties that characterizes the bond interface. The increment of Young Modulus leads to increment of dielectric constant and loss factor for epoxy resin and acrylates, respectively.
  • Publication
    In vitro biodegradation, cytotoxicity, and biocompatibility of polylactic acid/napier cellulose nanofiber scaffold composites
    ( 2022-12-31)
    Revati R.
    ;
    Mohd Shukry Abdul Majid
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Normahira Mamat @ Mohamad Nor
    ;
    Cheng Ee Meng
    ;
    Alshahrani H.A.
    This study aimed to evaluate the bioactivities and biocompatibilities of porous polylactic acid (PLA) reinforced with cellulose nanofiber (CNF) scaffolds. The in vitro degradation behaviors of the porous PLA/CNF scaffolds were systematically measured for up to 8 weeks in a phosphate-buffered saline medium at 37 °C. The reinforcement of CNF resisted the biodegradation of the scaffolds. The in vitro cytotoxicity and biocompatibility of the scaffolds were determined using the Beas2B American Type Culture Collection cells. The 3-(4,5-cimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide cytotoxicity and proliferation tests showed that the scaffolds were non-toxic, and epithelial cells grew well on the scaffold after 7 days of culture, whereas the percentage of cell proliferation on the PLA/CNF15 scaffold was the largest, 130 %. A scratch wound-healing assay was performed to evaluate the suitability of the scaffolds for cell migration. The results demonstrated that the scaffolds exhibited good cell migration towards nearly complete wound closure.
  • Publication
    Regression analysis of the dielectric and morphological properties for Porous Nanohydroxyapatite/Starch composites: a correlative study
    ( 2022)
    Chong You Beh
    ;
    Cheng Ee Meng
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Mohd Shukry Abdul Majid
    ;
    Khor Shing Fhan
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Emma Ziezie Mohd Tarmizi
    ;
    Kim Yee Lee
    This paper aims to investigate the dielectric properties, i.e., dielectric constant (ε′), dielectric loss factor (ε″), dielectric tangent loss (tan δ), electrical conductivity (σ), and penetration depth (Dp), of the porous nanohydroxyapatite/starch composites in the function of starch proportion, pore size, and porosity over a broad band frequency range of 5 MHz–12 GHz. The porous nanohydroxyapatite/starch composites were fabricated using different starch proportions ranging from 30 to 90 wt%. The results reveal that the dielectric properties and the microstructural features of the porous nanohydroxyapatite/starch composites can be enhanced by the increment in the starch proportion. Nevertheless, the composite with 80 wt% of starch proportion exhibit low dielectric properties (ε′, ε″, tan δ, and σ) and a high penetration depth because of its highly interconnected porous microstructures. The dielectric properties of the porous nanohydroxyapatite/starch composites are highly dependent on starch proportion, average pore size, and porosity. The regression models are developed to express the dielectric properties of the porous nanohydroxyapatite/starch composites (R2 > 0.96) in the function of starch proportion, pore size, and porosity from 1 to 11 GHz. This dielectric study can facilitate the assessment of bone scaffold design in bone tissue engineering applications.
  • Publication
    Swelling behaviors of composite film with alternating fibre reinforcement and aqueous media
    ( 2021-10-25)
    Rohadi T.N.T.
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Mohd Shukry Abdul Majid
    ;
    Cheng Ee Meng
    ;
    Norasni M.J.
    ;
    Marsi N.
    The swelling behaviour can affect the mechanical properties of the composite film and altering their ability to recover adsorbed substances. These problems are particularly important in the case of porous polymers. Therefore, several researchers have tried to improve the swelling properties by reducing the hydrophilic properties of gelatine and chitosan with adding reinforcing fillers. In this paper, the addition of the hydrophobic properties of pith and cortex of Napier grass in the chitosan/gelatin composite film will be investigated. The composite films were prepared via solution casting method will be evaluated based on the swelling behaviour in the alkali, neutral and acid solution. The result shows that type of reinforcement material and aqueous media used would affect the swelling behaviour of composite film. The results also suggest that the chitosan/gelatin composite films with incorporated cortex of Napier grass are the most water-resistant in neutral followed with acid and alkali.
  • Publication
    Effect of multi-walled carbon nanotube loading on the dielectric properties of polylactic acid
    ( 2024-03-07)
    Nur Azila Azahari
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Mohd Shukry Abdul Majid
    ;
    Maslinda A.B.
    ;
    Cheng Ee Meng
    ;
    Khor Shing Fhan
    Dielectric materials which capable to store charges are constantly being developed and improved for electronic applications such as in microelectronic integrated circuits (ICs). In this study, polylactic acid (PLA)/multiwalled carbon nanotube (MWCNT) composites are prepared and their dielectric properties are investigated. PLA/MWCNT composites have PLA as the matrix and MWCNT as filler with a loading of 1 wt%. The composites are porous composites achieved by using solvent casting and particulate leaching (SCPL) method. A frequency range of 1 kHz to 1 MHz is applied to measure the dielectric properties at room temperature. The PLA/MWCNT composites are categorized as low-k dielectric materials looking at the results of the dielectric test.
  • Publication
    Electrical conductivity of graphene-glass and carbon-glass epoxy composites
    ( 2024-04-22)
    Ahmad M.A.A.
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Mohd Shukry Abdul Majid
    ;
    Ismail M.S.
    ;
    Cheng Ee Meng
    In this paper, an experimental investigation is conducted to examine the electrical conductivity of glass epoxy composites containing graphene and carbon nanofillers. The hand lay-up technique was used to fabricate the GN-glass, MWCN-glass, and GN-MWCN-glass hybrid epoxy composites. The nanofiller weight fraction at 1.5 and 3 wt. % was analysed. The electrical conductivity test was carried out using two-probe methods to evaluate the GN and MWCN nanofiller's contribution to forming conductive networks within the epoxy matrix and glass fibre. The result indicates a higher electrical conductivity value of GN-MWCN-glass hybrid epoxy composites due to hybrid nanofillers incorporation. Field emission scanning electron microscope analyses the nanofiller's dispersion and random distribution in the composites. The good conductivity was related to the better bond formation of the nanofillers with the epoxy matrix. The electrical conductivity results obtained from this study will serve as a basis for investigating the correlation between electrical resistance and strain characteristics in the self-sensing monitoring composite for future research.