Cheng Ee Meng
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Preferred name
Cheng Ee Meng
Official Name
Cheng, Ee Meng
Alternative Name
Cheng, E. M.
Cheng, Ee M.
Cheng, Ee Meng
Main Affiliation
Scopus Author ID
57219023469
Researcher ID
IOQ-9149-2023

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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
    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
    Preliminary study of the polymesoda expansa based hydroxyapatite for medical devices coating application
    ( 2020-12-15)
    Roslan M.R.
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Gilani M.A.
    ;
    Nur Farahiyah Mohammad
    ;
    Cheng Ee Meng
    ;
    Khalid M.F.A.
    ;
    Zoolfakar A.S.
    ;
    Nasrul Amri Mohd Amin
    ;
    Shah Fenner Khan Mohamad Khan
    Hydroxyapatite (HA) which is a group of calcium phosphate (CaP) is used as a medical devices coating due to its ability to increase the bioactivity and biocompatibility of the device surface. The attraction of using waste seashells products is interesting due to its sustainability and low cost solution especially in biomedical application. Polymesoda expansa or locally known as Lokan is potentially rich with calcium carbonate (CaCO3). Here, the synthesis of HA was done via precipitation method by utilizing the Polymesoda expansa (Lokan) shells as the resource of calcium precursors. Hydroxyapatite synthesized from Polymesoda expansa was carried out with different pH solution (pH 9 and 13) in alkaline environment. The effects of pH on the morphological and chemical composition properties as well as the Ca/P ratio of HA powders were analyzed through Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and Energy Dispersive X-ray Spectrometry (EDS). The finding demonstrates as the pH increases, the calcium apatite reduced and this had increases the Ca/P ratio.
  • 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
    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
    Mineral composition, crystallinity and dielectric evaluation of Bamboo Salt, Himalaya Salt, and Ba’kelalan salt content
    ( 2024)
    Cheng Ee Meng
    ;
    Che Wan Sharifah Robiah Mohamad
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Khor Shing Fhan
    ;
    Ong Hong Liang
    ;
    Tan Xiao Jian
    ;
    Lee Kim Yee
    ;
    You Kok Yeow
    ;
    Emma Ziezie Mohd Tarmizi
    ;
    Mohd Riza Mohd Roslan
    ;
    Siti Aishah Baharuddin
  • Publication
    Microwave reflection measurement on thermal degradation of animal and vegetable oils
    ( 2022-10-01)
    Cheng Ee Meng
    ;
    Shahriman Abu Bakar
    ;
    Tan W.H.
    ;
    Mohd Afendi Rojan
    ;
    Khor Shing Fhan
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Robiah M.C.W.S.
    ;
    You K.Y.
    In this work, the reflection measurement on animal and vegetable oils due to different heating temperature was conducted using Agilent E8362B slim probe in conjunction with Agilent E8362B PNA Network Analyzer. The effect of thermal degradation on measured reflection efficient (Γ) is investigated. Many chemical processes are occurred when edible oils are heated during frying process. The thermal degradation products, i.e., volatile and non-volatile chemical compounds are generated. The generated volatile chemical compounds are dangerous to human health. Products of thermal degradation of animal and vegetable oils can be carcinogenic. On the other hand, it may cause diabetes, atherosclerosis, Alzheimer’s and Parkinson’s diseases, coronary heart disease, sudden cardiac death, and systemic vasculitis. Slim probe and open ended coaxial sensor are implemented to measure the reflection coefficient of the cooking oils. The fresh animal fats and vegetable oils are commercially available in local market. Five types of cooking oil (i.e. corn oil, olive oil, palm oil, sunflower oil and walnut oil) were measured at the temperature of 60ºC, 80ºC and 100 ºC for the frequency range of 3 GHz to 8GHz. When the oil is subjected to thermal degradation during heating, the chemical chain of oil will be altered and resulting in physical and internal properties change. It is the key element that led to the variation of Γ. Γ is function of physical-chemical properties of cooking oil that implying the oil quality. In reflection measurement, there are different noticeable results which indicates the used and fresh cooking oil and the effect of heating period
  • Publication
    Development of five port reflectometer for reflection based sensing system
    ( 2017-03-13)
    Setno Baharuddin
    ;
    Cheng Ee Meng
    ;
    Lee Kim Yee
    ;
    Siti Khadijah Za'aba
    ;
    Nurul Syahirah Khalid
    ;
    Zulkifly Abbas
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Mohd Afendi Rojan
    ;
    Zulkarnay Zakaria
    Five-Port Reflectometer is a microwave passivedevice where it implements the six-port algorithm to measure the complex reflection coefficient of material under test (MUT) through reflection on interface between MUT and microwave sensor. Initially, the Six-Port Reflectometer (SPR) was introduced by Engen in 1977 and major component used insix-port technique was designed in many types. When Riblet and Hanssonproposed ring junction with 5 ports only on 1981. Six ports ring junction has been reduced to five ports. In this paper, a dual frequency five ports ring junction circuit was designed, simulated and fabricated for reflection based sensing system. The fabricated five port ring junction is operating at frequencies of 0.64 GHz and 2.42 GHz. The measured result had good agreement with the simulated results for dual frequencies in terms of magnitude and phase.
  • Publication
    Dielectric and Colorimetric Analysis on Thermal Degradation of Cooking Oil
    ( 2021-01-01)
    Cheng Ee Meng
    ;
    Zakaria A.
    ;
    Bakar S.A.
    ;
    Kheng E.S.
    ;
    Ahmad Nasrul Norali
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Fhan K.S.
    ;
    Mohd Shukry Abdul Majid
    ;
    Yee L.K.
    ;
    Mohd Ridzuan Mohd Jamir
    In this work, dielectric and colorimetric properties of cooking oil is investi-gated for quality of cooking oil. An interdigitated electrode sensor (IDE), RGB colour detector and LCR (inductance–capacitance–resistance) meter were used to study colorimetric properties. The measured data was analyzed using principal component analysis, differential evolution feature extraction and major voting fusion. In dielectric measurement, there are different re-markable signal pattern which indicates the resistance change for used and fresh cooking oil. In addition, ten frequencies which can provide distinctive pattern were selected using differential evolution feature extraction. Nine types of cooking oil are then classified into used and fresh oil class. Major voting fusion exhibit 83% accuracy in classifying the oil. In the meantime, it can distinguish the used and fresh vegetable oils with approximately 100% accuracy. On the other hand, the results of colorimetric measurement indi-cate that this method can determine quality of frying oil accurately based on its type of oil, oil freshness, and duration of oil to fry.
  • Publication
    Biodegradation of PLA-Pennisetum purpureum based biocomposite scaffold
    ( 2017-10-29)
    Revati R.
    ;
    Mohd Shukry Abdul Majid
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Normahira Mamat @ Mohamad Nor
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Cheng Ee Meng
    The in vitro degradation and mechanical properties of a 3D porous Pennisetum purpureum (PP)/polylactic acid (PLA) - based scaffold was investigated. In this study, composite scaffolds with PP to PLA ratio of 0%, 10%, 20%, and 30% were immersed in PBS solution at 37 °C for 40 days. Interestingly, the degradation rate was reduced for the PLA/PP20 scaffold, though insignificantly, this could be attributed to the improved mechanical properties and stronger fibre-matrix interface. The FESEM results indicated that a sound fibre-matrix interface was formed in the PLA/PP20 scaffold, which reflected the addition of P. purpureum into PLA decreasing the degradation rate compared to in pure PLA scaffolds. The results suggest that the P. purpureum/PLA scaffold degradation rate can be altered and controlled to meet the requirement imposed by a given tissue engineering application.