Liew Yun Ming
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Liew Yun Ming
Official Name
Liew Yun Ming
Alternative Name
Yun-Ming, Liew
Liew, Y. M.
Yun Ming, Liew
Ming, Liew Yun
Liew, Yun Ming
Ming, L. Y.
Main Affiliation
Scopus Author ID
57204242778
Researcher ID
S-7164-2019

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  • Publication
    Functionalized carbon nanotube - modified ELISA for early detection of heart attack
    ( 2023-12)
    Emily M. Y. Chow
    ;
    Foo Kai Loong
    ;
    Subash Chandra Bose Gopinath
    ;
    Tan Soo Jin
    ;
    M. Kashif
    ;
    Heah Cheng Yong
    ;
    Liew Yun Ming
    A warning issue of heart attacks in young adults needs immediate attention lately. Enzyme-linked immunosorbent assay (ELISA) is an easy and commonly used method for detecting early stages of heart attack. Cardiac troponin I (cTnI) is a responsible biomarker for acute myocardial infarction. However, the conventional ELISA system was only able to detect at 100 pM of cTnI. To improve the system, enhancements were introduced through the integration of functionalized carbon nanotube (fCNT) to amplify cTnI detection signals. By utilizing the advantage of fCNT, a noticeable improvement in results can be obtained. The detection limit was lowered down to an impressive 10 pM. Furthermore, the change of absorbance increased from 31.90% for conventional ELISA surge to 98.61 for modified ELISA system. This three-fold increase in sensitivity shows remarkable improvement through the introduction of fCNT in modified ELISA technique.
  • Publication
    Preparation of fly Ash-Ladle furnace slag blended geopolymer foam via Pre-Foaming method with polyoxyethylene alkyether sulphate incorporation
    ( 2022)
    Ng Hui-Teng
    ;
    Heah Cheng Yong
    ;
    Liew Yun Ming
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Catleya Rojviriya
    ;
    Hasniyati Md Razi
    ;
    Sebastian Garus
    ;
    Marcin Nabiałek
    ;
    Wojciech Sochacki
    ;
    Ilham Mukriz Zainal Abidin
    ;
    Ng Yong-Sing
    ;
    Andrei Victor Sandu
    ;
    Agata Śliwa
    This paper uses polyoxyethylene alkyether sulphate (PAS) to form foam via pre-foaming method, which is then incorporated into geopolymer based on fly ash and ladle furnace slag. In the literature, only PAS-geopolymer foams made with single precursor were studied. Therefore, the performance of fly ash-slag blended geopolymer with and without PAS foam was investigated at 29–1000 °C. Unfoamed geopolymer (G-0) was prepared by a combination of sodium alkali, fly ash and slag. The PAS foam-to-paste ratio was set at 1.0 and 2.0 to prepare geopolymer foam (G-1 and G-2). Foamed geopolymer showed decreased compressive strength (25.1–32.0 MPa for G-1 and 21.5–36.2 MPa for G-2) compared to G-0 (36.9–43.1 MPa) at 29–1000 °C. Nevertheless, when compared to unheated samples, heated G-0 lost compressive strength by 8.7% up to 1000 °C, while the foamed geopolymer gained compressive strength by 68.5% up to 1000 °C. The thermal stability of foamed geopolymer was greatly improved due to the increased porosity, lower thermal conductivity, and incompact microstructure, which helped to reduce pressure during moisture evaporation and resulted in lessened deterioration.
  • Publication
    Effect of anisotropic pores on the material properties of metakaolin geopolymer composites incorporated with corrugated fiberboard and rubber
    ( 2021)
    Nur Ain Jaya
    ;
    Liew Yun Ming
    ;
    Heah Cheng Yong
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Low Foo Wah
    ;
    Ooi Wan-En
    ;
    Ilham Mukriz Zainal Abidin
    ;
    Noorhazleena Azaman
    This paper compares the compressive strength and thermal conductivity of metakaolin geopolymer (MKG) incorporated with anisotropic and isotropic pores. MKG was prepared by activation with sodium hydroxide and sodium silicate. Corrugated fiberboard and rubber were included to create anisotropy of pores, and they were added in 3, 5, and 7 layers. Hydrogen peroxide and surfactant were added to generate isotropic pores. For geopolymer with corrugated fiberboard (MKG-C) and rubber (MKG-R), compressive test and thermal conductivity measurement were performed in perpendicular and parallel direction to the flat surface of fiberboard and rubber. The result showed that MKG-C and MKG-R exhibited mechanical and insulation anisotropically. The highest compressive strength was achieved in the parallel loading direction while the lowest thermal conductivity was attained in the perpendicular direction. MKG-C possessed better compressive strength of 26.9 MPa loaded in the parallel direction. The compressive strength performance of MKG-C was greater than MKG-R because of the fibrous-like structure, which further contributes to the strength. The thermal conductivity was low (0.15–0.20 W/mK) for both MKG-C and MKG-R. The anisotropy of pores led to high strength retention and improvement of thermal insulating properties. These properties were contrary to geopolymer with isotropic pores (MKG-F), which have excellent thermal insulating properties but low compressive strength to be eligible for structural applications.
  • Publication
    Ladle furnace slag replacement on the flexural strength of thin fly ash geopolymer
    ( 2020)
    Ng YONG-SING
    ;
    Liew Yun Ming
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Ng HUI-TENG
    ;
    Ridho BAYUAJI
    This article reports the investigation on the effect of ladle furnace slag replacement on the flexural strength of thin fly ash-based geopolymer. The thin fly ash/slag geopolymers were prepared with the replacement of various percentages of ladle furnace slag (0%, 10%, 20%, 30% and 40%) into fly ash geopolymers with dimension of 160 mm × 40 mm × 10 mm. The thin geopolymerwas synthesised using 12M sodium hydroxide (NaOH) solution with solid-to-liquid (S/L) ratio of 2.5 and Na2SiO3 /NaOH ratio of 4.0. The curing temperature and time of samples were 60°C and 6 hours respectively. The mechanical properties of thin geopolymers was revealed using flexural test after 28 days. Several characterisation tools have been used including Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD) to correlate the flexural properties with the microstructure and phases of fly ash/slag geopolymers. Results obtained reported that a positive effect on flexural strength was observed with the increasing amount of slag. The thin fly ash geopolymers replaced with 40% of ladle furnace slag showed the highest flexural strength of 7.8 MPa. The rich CaO content in ladle furnace slag boosted the C-S-H gels formation which increased the flexural strength of thin geopolymers.
  • Publication
    Elevated-Temperature performance, combustibility and fire propagation index of Fly Ash-Metakaolin blend geopolymers with addition of Monoaluminium Phosphate (MAP) and Aluminum Dihydrogen Triphosphate (ATP)
    ( 2021)
    Khairunnisa Zulkifly
    ;
    Heah Cheng Yong
    ;
    Liew Yun Ming
    ;
    Ridho Bayuaji
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Shamsul Bin Ahmad
    ;
    Tomasz Stachowiak
    ;
    Janusz Szmidla
    ;
    Joanna Gondro
    ;
    Bartłomiej Jeż
    ;
    Mohd Suhaimi Bin Khalid
    ;
    Sebastian Garus
    ;
    Ong Shee-Ween
    ;
    Ooi Wan-En
    ;
    Ng Hui-Teng
    Thermal performance, combustibility, and fire propagation of fly ash-metakaolin (FA-MK) blended geopolymer with the addition of aluminum triphosphate, ATP (Al(H2PO4)3), and monoaluminium phosphate, MAP (AlPO4) were evaluated in this paper. To prepare the geopolymer mix, fly ash and metakaolin with a ratio of 1:1 were added with ATP and MAP in a range of 0–3% by weight. The fire/heat resistance was evaluated by comparing the residual compressive strengths after the elevated temperature exposure. Besides, combustibility and fire propagation tests were conducted to examine the thermal performance and the applicability of the geopolymers as passive fire protection. Experimental results revealed that the blended geopolymers with 1 wt.% of ATP and MAP exhibited higher compressive strength and denser geopolymer matrix than control geopolymers. The effect of ATP and MAP addition was more obvious in unheated geopolymer and little improvement was observed for geopolymer subjected to elevated temperature. ATP and MAP at 3 wt.% did not help in enhancing the elevated-temperature performance of blended geopolymers. Even so, all blended geopolymers, regardless of the addition of ATP and MAP, were regarded as the noncombustible materials with negligible (0–0.1) fire propagation index.
  • Publication
    Thermal Insulation and Mechanical Properties in the Presence of Glas Bubble in Fly Ash Geopolymer Paste
    ( 2022-01-01)
    Shahedan N.F.
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Norsuria Mahmed
    ;
    Liew Yun Ming
    ;
    Shayfull Zamree Abd. Rahim
    ;
    Aziz I.H.A.
    ;
    Kadir A.A.
    ;
    Sandu A.V.
    ;
    Mohd Fathullah Ghazli@Ghazali
    The density, compressive strength, and thermal insulation properties of fly ash geopolymer paste are reported. Novel insulation material of glass bubble was used as a replacement of fly ash binder to significantly enhance the mechanical and thermal properties compared to the geopolymer paste. The results showed that the density and compressive strength of 50% glass bubble was 1.45 g/ cm3 and 42.5 MPa, respectively, meeting the standard requirement for structural concrete. Meanwhile, the compatibility of 50% glass bubbles tested showed that the thermal conductivity (0.898 W/mK), specific heat (2.141 MJ/m3K), and thermal diffusivity (0.572 mm2/s) in meeting the same requirement. The improvement of thermal insulation properties revealed the potential use of glass bubbles as an insulation material in construction material.
  • Publication
    Turning waste into strength enhancing geopolymer composites with Oil Palm Frond Fibers (OPF)
    ( 2024-10)
    Ng Hui-Teng
    ;
    Liew Yun Ming
    ;
    Heah Cheng Yong
    ;
    Tan Soo Jin
    ;
    Muhammad Aqil Asyraf Bin Mohd Roslan
    ;
    Siti Khadijah Binti Zulkepli
    ;
    Tan You How
    ;
    Ng Yong-Sing
    Geopolymers are alternatives to ordinary Portland cement as construction materials. The increasing demand for sustainable construction materials has driven the utilization of industrial by-products and agricultural waste. The disposal of oil palm frond (OPF) biomass as waste in landfills poses significant environmental challenges, necessitating effective recycling strategies. This study examines the incorporation and feasibility of OPF as a reinforcing fiber in fly ash geopolymer composites, examining its impact on physical and mechanical properties. Various parameters were tested, including fiber content (10–20 wt.%), shapes (shredded and tubular), and lengths (1–3 cm). The geopolymer composites with 10 wt.% shredded oil palm frond and 1-cm tubular oil palm frond fibers enhance the compressive strength by 17% compared to the control sample without oil palm frond. The shredded oil palm frond was particularly effective, enhancing strength performance and achieving better dispersion within the geopolymer matrix. Conversely, increasing the fiber content and length generally resulted in diminished composite strength, attributed to the creation of a more porous structure and weaker fiber-matrix interactions. However, lower fiber additions were shown to decrease porosity and water absorption, highlighting the potential of optimized oil palm frond fiber content and form in improving the environmental and mechanical performance of geopolymer composites. These results support the viability of oil palm frond as a sustainable additive in geopolymers, contributing to waste reduction and material innovation in construction.
  • Publication
    Diverse material based geopolymer towards heavy metals removal : a review
    ( 2023)
    Pilomeena Arokiasamy
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Shayfull Zamree Abd. Rahim
    ;
    Monower Sadique
    ;
    Liew Yun Ming
    ;
    Mohd Arif Anuar Mohd Salleh
    ;
    Mohd Remy Rozainy Mohd Arif Zainol
    ;
    Che Mohd Ruzaidi Ghazali
    Metakaolin is a commonly used aluminosilicate material for the synthesis of geopolymer based adsorbent. However, it presents characteristics that restrict its uses such as weak rheological properties brought on by the plate-like structure, processing challenges, high water demand and quick hydration reaction. Industrial waste, on the other hand, contains a variety of components and is a potential source of aluminosilicate material. Geopolymer adsorbent synthesized by utilizing industrial waste contains a wide range of elements that offer better ion-exchangeability and increase active sites on the surface of geopolymer. However, limited studies focused on the synthesized of geopolymer based adsorbent by utilizing industrial waste for heavy metal adsorption in wastewater treatment. Therefore, this paper reviews on the raw materials used in the synthesis of geopolymer for wastewater treatment. This would help in the development of low cost geopolymer based adsorbent that has a great potential for heavy metal adsorption, which could deliver double benefit in both waste management and wastewater treatment.
  • Publication
    Flexural properties of thin fly ash geopolymers at elevated temperature
    ( 2021)
    Yong-Sing Ng
    ;
    Liew Yun Ming
    ;
    Heah Cheng Yong
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Hui-Teng Ng
    ;
    Lynette Wei Ling Chan
    This paper reports on the flexural properties of thin fly ash geopolymers exposed to elevated temperature. The thin fly ash geopolymers (dimension = 160 mm × 40 mm × 10 mm) were synthesised using12M NaOH solution mixed with designed solidsto-liquids ratio of 1:2.5 and Na2SiO3/NaOH ratio of 1:4 and underwent heat treatment at different elevated temperature (300°C, 600°C, 900°C and 1150°C) after 28 days of curing. Flexural strength test was accessed to compare the flexural properties while X-Ray Diffraction (XRD) analysis was performed to determine the phase transformation of thin geopolymers at elevated temperature. Results showed that application of heat treatment boosted the flexural properties of thin fly ash geopolymers as the flexural strength increased from 6.5 MPa (room temperature) to 16.2 MPa (1150°C). XRD results showed that the presence of crystalline phases of albite and nepheline contributed to the increment in flexural strength.
  • Publication
    The effect of different ratio bottom ash and fly ash geopolymer brick on mechanical properties for non-loading application
    ( 2017)
    Laila Mardiah Deraman
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Liew Yun Ming
    ;
    Kamarudin Hussin
    ;
    Wan Mastura Wan Ibrahim
    ;
    Andrei Victor Sandu
    This paper studies the finding of strength and water absorption of geopolymer bricks using bottom ash and fly ash as a geopolymer raw material for non-loading application with minimum strength. The study has been conducted to produce bottom ash and fly ash geopolymer bricks by varying the ratio of fly ash-to-bottom ash, solid-to-liquid and sodium silicate (Na2SiO3)-to-sodium hydroxide (NaOH) in the mixing process. The compressive strength range between 3.8-4.5 MPa was obtained due to the minimum strength of non-loading application with 70°C curing temperature within 24 hours at 7 days of ageing. The optimum ratio selected of bottom ash-to-fly ash, solid-to-liquid and Na2SiO3-to-NaOH are 1:2, 2.0 and 4.0 respectively. The water absorption result is closely related to the amount of bottom ash used in the mix design.