Khor Shing Fhan
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Preferred name
Khor Shing Fhan
Official Name
Shing Fhan, Khor
Alternative Name
Khor, S. F.
Fhan, Khor Shing
Shing, Fhan Khor
Khor, Shing F.
Shing Fhan, Khor
Main Affiliation
Scopus Author ID
35242874900
Researcher ID
W-7216-2019

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  • Publication
    Dielectric spectroscopy technique for carbohydrate characterization of fragrant rice, brown rice and white rice
    ( 2017-11-20)
    Cheng Ee Meng
    ;
    Kok Yeow You
    ;
    Lee KimYee
    ;
    Abbas Z.
    ;
    Hasliza A Rahim @ Samsuddin
    ;
    Khor Shing Fhan
    ;
    Zulkarnay Zakaria
    ;
    Lee Y.S.
    This study was conducted to investigate the feasibility of microwave dielectric spectroscopic technique in characterizing commercial rice due to different level of moisture content. There are some unethical rice industry runner mixes good qualities of rice which can be sold at high price with low cost and quality of rice to maximize profit. It causes fraudulency in business and great lost in term of money to nation who take rice as staple food. It happens frequently in Asian country which is active in agricultural activities. This technique is implemented using Keysight E8362B network analyzer in conjunction with an Keysight 85070E dielectric probe ranging from 200 MHz to 10 GHz. The samples of study are commercially available at market, namely fragrant rice, white rice, and brown rice, respectively. These are the popular and favorite rice for Malaysian due its delicacy and affordable price. Nutrient level for fragrant rice, white rice, and brown rice in terms of protein, moisture, carbohydrate and fat are different and unique. It leads to various electromagnetic responses toward frequency. Dielectric and reflection measurement were conducted to characterize these rice. The presence of polar and non-polar molecules in nutrient of rice causes variation of dielectric and reflection behavior over the operating frequency range.
  • Publication
    The effect of pressing load on 8 mol% Yttria stabilized Zirconia grade 204NS-G
    (Trans Tech Publications Ltd., 2020-09)
    Tinesha Selvaraj
    ;
    Banjuraizah Johar
    ;
    Khor Shing Fhan
    The aim of this study is to understand the compaction characteristics of as received granulated 8 mol% yttria-stabilized zirconia (8YSZ). The samples were compacted at different loads and sintered at 1550 °C with the heating rate of 5°C/min for 5 hours. The densification, morphology analysis and crystal structure of the sintered were compared. The densification of granulated 8YSZ achieved 67% as increasing pressing load (0.1 tonne to 0.4 tonne). Rietveld quantitative phase analysis demonstrates that the tetragonal-ZrO2 phase reduces in granulated 8YSZ. The amount of cubic-ZrO2 phase dramatically dropped for both granulated as the pressing load increased. From the morphology analysis, granulated sample found to be porous observed on the surface as compaction load applied. Compaction load has no significant effect on the densification of granule sintered 8YSZ in the current study. The maximum densification was only reached 67% by using granulated 8YSZ powder with 0.4 tonne pressing load.
  • Publication
    The thermal behavior of cordierite-based ceramic with the substitution of treated flue gas desulfurization sludge in the non-stoichiometric cordierite composition
    (Springer, 2023)
    Fatin Fatini Othman
    ;
    Banjuraizah Johar
    ;
    Khor Shing Fhan
    ;
    Nik Akmar Rejab
    ;
    Suffi Irni Alias
    The substitution of FGD sludge that is rich with a glass-forming agent in non-stoichiometric cordierite composition is able to crystallize α-cordierite at the low sintering temperature, 1250 °C via solid-state reaction methods. Even though the substitution of MgO with FGD sludge can reduce the sintering temperature, the physical and mechanical properties of cordierite-based ceramic with FGD sludge are depleted due to the decomposition of SO3 took place during the sintering process and thus lead to the formation of voids in the ceramic. Thus, this paper is focusing on the thermal properties of cordierite-based ceramic when subjected to a high sintering temperature, 1000 °C using a dilatometric test. Different wt% of treated FGD sludge substitution gave a different type of CTE value, but 3.0 wt% of FGD sludge is able to obtain the lowest CTE value, 2.26 × 10–6/°C, compared to other samples as this sample obtains a single phase of α-cordierite phases.
  • Publication
    The mechanochemical process and Hâ‚‚SOâ‚„ treatment on the rehydration of Anhydrite from FGD sludge into Gypsum and Hemihydrate
    (Springer, 2023)
    Fatin Fatini Othman
    ;
    Banjuraizah Johar
    ;
    Khor Shing Fhan
    ;
    Nik Akmar Rejab
    ;
    Suffi Irni Alias
    The rehydration of anhydrite (CaSO₄) leads to the crystallization of gypsum (CaSO₄⋅2H₂O) has been widely studied. Different process parameter had been conducted on anhydrite from the flue gas desulphurization (fgd) sludge to identify its ability to be reused as synthetic gypsum. A mechanochemical process using a high-energy planetary mill would break down the particle size and enhance the reaction of Ca²+ and SO₄ ²− with water while additives modify the number of ions present in the sample during the hydration. Difference hydrothermal temperatures (80 and 130 °C) for 30 min were conducted to dehydrate the synthetic gypsum from fgd sludge to hemihydrate (CaSO₄⋅0.5H₂O) to identify its potential to replace natural gypsum during the plaster of Paris production. The sample without a mechanochemical process wasn’t able to crystallize a high amount of gypsum while sample with 5 × 10–4 mol−1 of H₂SO₄ additive was able to crystallize a high amount of gypsum from the fgd sludge. After undergoing the hydrothermal process, all of the samples were able to crystallize hemihydrate at low-intensity peak due to the favourable of hemihydrate crystal’s growth at plane [31-3] only, which leads to the preferred orientation of hemihydrate crystal.
  • Publication
    A Comprehensive Review of Midrange Wireless Power Transfer Using Dielectric Resonators
    ( 2021-01-01)
    Azuwa Ali
    ;
    Mohd Najib Mohd Yasin
    ;
    Faiz Wan Ali W.F.
    ;
    Norsuria Mahmed
    ;
    Kamarudin M.R.
    ;
    Ismahayati Adam
    ;
    Muzammil Jusoh
    ;
    Hasliza A Rahim @ Samsuddin
    ;
    Khor Shing Fhan
    ;
    Nurulazlina Ramli
    ;
    Norshamsuri Ali @ Hasim
    Magnetic resonant coupling (MRC) is one of the techniques that are widely used in wireless power transfer (WPT) systems. The technique is commonly used for enhancing distance while maintaining power transfer efficiency (PTE). Many studies have investigated new technologies to extend the distance of MRC while maintaining high PTE values. The most promising technique to date in MRC is the addition of a resonator between the transmitter and the receiver coil. The implementation of the resonator varies based on different designs, sizes, and material types, although the outcomes remain unsatisfactory. By introducing dielectric material resonators, PTE can be improved by lowering the ohmic loss which becomes a problem on conventional resonators. This study presents a general overview on the use of dielectric material as a resonator in MRC WPT technology and its technological development. The basic operation of MRC WPT is summarized with up-to-date technical improvements related to dielectric material as a resonator in the field of WPT. An overview of the current limitations and challenges of this technique is also highlighted in this study.
      1
  • Publication
    Morphological and optical properties of porous hydroxyapatite/cornstarch (HAp/Cs) composites
    ( 2020-01-01)
    Beh C.Y.
    ;
    Cheng Ee Meng
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Mohd Tarmizi E.Z.
    ;
    Eng S.K.
    ;
    Mohd Shukry Abdul Majid
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Khor Shing Fhan
    ;
    Ahmad Saad F.S.
    This paper presents the correlation between the morphological characteristics and the diffuse reflectance (optical properties) of the porous hydroxyapatite/cornstarch (HAp/Cs) composites with various starch proportions (30, 40, 50, 60, 70, 80 and 90 wt%). The porous composites were measured via SEM and enhanced by image processing to find the average pore size, strut width, and average surface roughness. The average porosity of the porous composites was measured using liquid displacement method. The diffuse reflectance spectroscopy was implemented to investigate the diffuse reflectance and the corresponding optical band gap energy of the porous composites in the 500e900 nm range. A relationship between morphological characteristics and diffuse reflectance properties were established using Pearson's correlation coefficient. The findings of the study depict that a strong correlation can be noticed between optical band gap energy with porosity, pore sizes and surface roughness of the porous composites. Meanwhile, the strong correlations between the diffuse reflectance spectral gradient with surface roughness can be observed. The moderate correlations can be observed between the diffuse reflectance spectral gradient with pore sizes and strut width of the porous composites.
      2
  • Publication
    Complex Impedance and Modulus Analysis on Porous and Non-Porous Scaffold Composites Due to Effect of Hydroxyapatite/Starch Proportion
    ( 2023-01-01)
    Beh C.Y.
    ;
    Cheng Ee Meng
    ;
    Tan X.J.
    ;
    Mohd Nasir N.F.
    ;
    Mohd Shukry Abdul Majid
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Khor Shing Fhan
    ;
    Lee K.Y.
    ;
    Che Wan Sharifah Robiah Mohamad
    This study aims to investigate the electric responses (complex modulus and complex impedance analysis) of hydroxyapatite/starch bone scaffold as a function of hydroxyapatite/starch proportion and the microstructural features. Hence, the non-porous and porous hydroxyapatite/starch composites were fabricated with various hydroxyapatite/starch proportions (70/30, 60/40, 50/50, 40/60, 30/70, 20/80, and 10/90 wt/wt%). Microstructural analysis of the porous hydroxyapatite/starch composites was carried out by using scanning electron microscopy. It shows that the formation of hierarchical porous microstructures with high porosity is more significant at a high starch proportion. The complex modulus and complex impedance analysis were conducted to investigate the electrical conduction mechanism of the hydroxyapatite/starch composites via dielectric spectroscopy within a frequency range from 5 MHz to 12 GHz. The electrical responses of the hydroxyapatite/starch composites are highly dependent on the frequency, material proportion, and microstructures. High starch proportion and highly porous hierarchical microstructures enhance the electrical responses of the hydroxyapatite/starch composite. The material proportion and microstructure features of the hydroxyapatite/starch composites can be indirectly reflected by the simulated electrical parameters of the equivalent electrical circuit models.
      4
  • Publication
    Low frequency dielectric and optical behavior on physicochemical properties of hydroxyapatite/cornstarch composite
    ( 2021-10-15)
    Beh C.Y.
    ;
    Cheng Ee Meng
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Khor Shing Fhan
    ;
    Eng S.K.
    ;
    Mohd Shukry Abdul Majid
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Lee K.Y.
    An investigation on relationship among the physicochemical, optical and dielectric properties of the hydroxyapatite/cornstarch (HA/Cs) composites with the starch proportion of 30, 40, 50, 60, 70, 80 and 90 wt% is presented in this work. The HA/Cs composites have been characterized via FTIR, XRD, DRS and impedance analyzer. This work depicts that the strong interaction is exhibited between the hydroxyapatite nanoparticles and starch as the starch proportion increases. This increment trend results in the higher crystallinity of the HA/Cs composites. The highly crystallized HA/Cs with hydroxyapatite nucleation center presents low optical properties (diffuse reflectance and optical band gap energy). The HA/Cs composite with 80 wt% starch proportion (H2C8) show higher dielectric properties (dielectric constant, loss factor and conductivity) due to the stronger interfacial interaction and close-packed HA/Cs crystalline structure. The relationship among the physicochemical, optical and dielectric properties of the HA/Cs composite is studied in this work for potential of instrumentation design.
      2  1
  • Publication
    Regression Analysis of the Dielectric and Morphological Properties for Porous Nanohydroxyapatite/Starch Composites: A Correlative Study
    ( 2022-05-01)
    Beh C.Y.
    ;
    Cheng Ee Meng
    ;
    Nashrul Fazli Mohd Nasir
    ;
    Mohd Tarmizi E.Z.
    ;
    Mohd Shukry Abdul Majid
    ;
    Mohd Ridzuan Mohd Jamir
    ;
    Lee K.Y.
    ;
    Khor Shing Fhan
    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.
      1  18
  • 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
      36  2