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Papers by Luqman Chuah Abdullah

ISRN Nanotechnology, 2011

This paper is trying to explore the effect of stirring time on the synthesis of nano-α-Alumina pa... more This paper is trying to explore the effect of stirring time on the synthesis of nano-α-Alumina particles. In this study, alumina nanoparticles were synthesized through alkoxide route using sol-gel method, where aqueous solutions of aluminum isopropoxide and 0.5 M aluminum nitrate nanohydrate were used for preparing alumina sol. Sodium dodecylbenzen sulfonate (SDBS) was used as the surfactant stabilizing agent. The prepared solution was stirred at different times (24, 36, 48, and 60 hours) at 60°C. The Samples were, then, characterized by X-ray diffraction, thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Transmission Electron Microscopy(TEM) . The introduction of different stirring times affected the particle size and shape and the degree of aggregation. By increasing the stirring time, (starting from 24 to 48 hours) the particle size decreased, but agglomeration became hard for 60 hours of stirring time. The finest par...

Processes, 2020

Encapsulation of dual compounds of different characters (hydrophilic and hydrophobic) in single n... more Encapsulation of dual compounds of different characters (hydrophilic and hydrophobic) in single nanoparticles carrier could reach the site of action more accurately with the synergistic effect but it is less investigated. In our previous findings, combined-compounds encapsulation and delivery from chitosan nanoparticles were impaired by the hydrophilicity of chitosan. Therefore, hydrophobic modification on chitosan with palmitic acid was conducted in this study to provide an amphiphilic environment for better encapsulation of antioxidants; hydrophobic thymoquinone (TQ) and hydrophilic l-ascorbic acid (LAA). Palmitoyl chitosan nanoparticles (PCNPs) co-loaded with TQ and LAA (PCNP-TQ-LAA) were synthesized via the ionic gelation method. Few characterizations were conducted involving nanosizer, Fourier-transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). UV–VIS spectrophotometry was used...

Pharmaceuticals contain biologically active components that can pollute water courses as a result... more Pharmaceuticals contain biologically active components that can pollute water courses as a result of the excretions from individuals and/or uncontrolled release of residues from chemical plants, and they can pose a hazard to health. Pharmaceutical residues can persist at low concentrations in the environment, and thus may be potentially harmful to aquatic animals and to humans. Controlling and monitoring such residues are therefore a prime interest, for example, a solid-phase extraction uses solid sorbents to purify and preconcentrate the residues prior to their chemical analysis. In the present study, poly (acrylonitrile-co-divinylbenzene-80) sorbents are synthesised by varying the comonomer feed ratios under precipitation polymerisation conditions to deliver a family of porous polymer microspheres. Acrylonitrile confers polar characters onto the sorbents, and the acrylonitrile-derived nitrile groups can be chemically transformed via polymer-analogous reactions into thioamide...

Journal of Vinyl and Additive Technology, 2009

Molecules, 2020

Bamboo fibers are utilized for the production of various structures, building materials, etc. and... more Bamboo fibers are utilized for the production of various structures, building materials, etc. and is of great significance all over the world especially in southeast Asia. In this study, the extraction of microcrystalline cellulose (MCC) was performed using bamboo fibers through acid hydrolysis and subsequently different characterizations were carried out using various advanced techniques. Fourier transform infrared (FTIR) spectroscopy analysis has indicated the removal of lignin from MCC extracted from bamboo pulp. Scanning Electron Microscopy (SEM) revealed rough surface and minor agglomeration of the MCC. Pure MCC, albeit with small quantities of impurities and residues, was obtained, as revealed by Energy Dispersive X-ray (EDX) analysis. X-ray diffraction (XRD) indicates the increase in crystallinity from 62.5% to 82.6%. Furthermore, the isolated MCC has slightly higher crystallinity compared to commercial available MCC (74%). The results of thermal gravimetric analysis (TGA) de...

International Journal of Nanotechnology, 2019

Molecules (Basel, Switzerland), Jan 29, 2017

A low cost, abundant, and renewable vegetable oil source has been gaining increasing attention du... more A low cost, abundant, and renewable vegetable oil source has been gaining increasing attention due to its potential to be chemically modified to polyol and thence to become an alternative replacement for the petroleum-based polyol in polyurethane production. In this study, jatropha oil-based polyol (JOL) was synthesised from non-edible jatropha oil by a two steps process, namely epoxidation and oxirane ring opening. In the first step, the effect of the reaction temperature, the molar ratio of the oil double bond to formic acid, and the reaction time on the oxirane oxygen content (OOC) of the epoxidised jatropha oil (EJO) were investigated. It was found that 4.3% OOC could be achieved with a molar ratio of 1:0.6, a reaction temperature of 60 °C, and 4 h of reaction. Consequently, a series of polyols with hydroxyl numbers in the range of 138-217 mgKOH/g were produced by oxirane ring opening of EJOs, and the physicochemical and rheological properties were studied. Both the EJOs and the...

Journal of oil palm research

The present invention discloses a method to manufacture nano-sized α-Al2O3 powders having a parti... more The present invention discloses a method to manufacture nano-sized α-Al2O3 powders having a particle size from about 15 nm to about 30 nm, whilst preventing excessive grain growth and aggregation of nanoparticles. In an aspect of the present invention, the particle size and shape of the nano α-Al2O3 powders can be controlled by using sodium dodecylbenzen sulfonate (SDBS) and sodium bis-2-ethylhexyl sulfosuccinate (Na(AOT)) as surfactant stabilizing agents. In another aspect, the size and shape of the nano α-Al2O3 powders can be controlled by forming aqueous solutions stirred for different periods of time, i.e 24, 36, 48 and 60 hours, at 60?C.

Handbook of Green Materials, 2014