Zainab Ngaini - Academia.edu (original) (raw)
Papers by Zainab Ngaini
Journal of Forensic Sciences, Aug 10, 2015
Paraquat poisoning is commonly associated with suicide or homicide in Malaysia. In a case involvi... more Paraquat poisoning is commonly associated with suicide or homicide in Malaysia. In a case involving advanced body decomposition, pathological analysis regarding the cause of death may become difficult or almost impossible. Insects serve as common alternative matrix for poison detection in forensic analysis. Paraquat detection via secondary bioaccumulation in fly larvae tissue has never been reported. In this study, tissues from blowfly larvae collected from a rabbit carcass with paraquat poisoning were analyzed for secondary bioaccumulation. Larvae samples were collected and analyzed using liquid-liquid extraction. The detection was performed via reduction of quaternary ammonium presence in paraquat and analyzed using gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring mode (SIM mode). GC-MS showed the elution of reduced paraquat was at retention time 12.8 min. Blowfly larvae tissue has proven useful as a secondary detector in paraquat-related deaths.
Elsevier eBooks, 2021
Knowledge and best practice in this field are constantly changing. As new research and experience... more Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary.
Malaysian Journal of Fundamental and Applied Sciences, Jul 24, 2014
The reactions of 3,4,6-tri-O-acetyl-D-glucal with phenolic and aliphatic alcohol in various Lewis... more The reactions of 3,4,6-tri-O-acetyl-D-glucal with phenolic and aliphatic alcohol in various Lewis acid catalysts (namely La(NO3)3.6H2O, InCl3, ZnCl2 and BF3•OEt2) have furnished the corresponding alkyl and aryl 2,3-unsaturated glycopyranosides via Ferrier rearrangement. BF3•OEt2 showed the best Lewis acids catalysts with excellent yields and minimum reaction times. The reactions performed in CH3CN gave better yields and shorter reaction times compared to CH2Cl2. The electron withdrawing properties of aromatic ring resulting lower yields of aryl 2,3-unsaturated glycopyranosides compared to alkyl 2,3-unsaturated glycopyranosides under this condition. This study is significant in the preparation of O-glycosides via Ferrier rearrangement.
Waste and Biomass Valorization, Mar 23, 2019
In this study, microwave induced pyrolytic oil from sago bark (SB) was subjected to esterificatio... more In this study, microwave induced pyrolytic oil from sago bark (SB) was subjected to esterification to improve its properties. Improvement on properties of the pyrolytic oil was performed via esterification with ethanol and the presence of sulfuric acid as a catalyst. The optimum esterification condition was studied using general factorial design. The esterified oil (EO) showed improved properties with pH (4-6), reduced moisture content (2.95-3.45%), density (0.9-1.1 g cm −3), and acid value (39.3-123.4 mg KOH −1 g −1), and maintained the CV (20.2-21.6 MJ kg −1). GC-MS analysis showed that EO was sulphur free, and low in carboxylic acid and oxygenated compounds. The optimal esterification condition with optimum quality of EO was at 65 °C temperature, 60 min reaction time and 1:1 ethanol to oil volume ratio. Results indicated that the EO can be potentially used in robust combustion engines upon properties refinement.
Environmental Science and Pollution Research, May 31, 2019
Sago bark (SB) and empty fruit bunch (EFB) are available abundantly as agricultural waste in Sara... more Sago bark (SB) and empty fruit bunch (EFB) are available abundantly as agricultural waste in Sarawak. This study was conducted to investigate the physicochemical characteristics of SB and EFB as composting materials and used as a plant growth medium. The SB and EFB composts were prepared in a separate container by mixing chicken manure as compost accelerator and wood chips as a bulking agent in dry weight equivalent ratio (1:1:1). The maturity and stability of compost in 60-day composting periods were evaluated via physicochemical characterization of the composts in terms of pH, elemental content, total ash content, moisture content and nutrient analyses. The effect of the compost usage as growth medium was assessed towards water spinach and green mustard via seed germination and pot study. After 2 months, the colour of both composts was dark brown with an earthy smell. The acidic pH of the initial composting stage has changed into alkaline pH after 60 days of composting. Total NPK present in the SB and EFB composts were 0.96% and 1.21%, respectively. The germination index (GI) for the studied vegetables was above 100%, while the pot study showed that vegetables in compost media has higher growth compared to the control, after 14 days. SB and EFB are renewable waste which can be used as an excellent compost and able to improve the quality of the soil.
Journal of Chemistry, 2017
Microwave pyrolysis is a potential for producing alternative fuel from biomass, such as palm kern... more Microwave pyrolysis is a potential for producing alternative fuel from biomass, such as palm kernel shell (PKS). However, the resulting microwave pyrolytic oil (bio-oil) was highly acidic and has low calorific value and therefore must undergo additional process to improve the physicochemical properties. In this study, attempt was made to improve the pH and calorific value of bio-oil produced from PKS via esterification process. The effect of esterification with ethanol in the presence of sulphuric acid as a catalyst on selected biodiesel qualities was also investigated. The esterification process has successfully improved the pH value from 3.37 to 5.09-5.12 and the calorific value was increased from 27.19 to 34.78-41.52 MJ/kg. Conclusively, the EO has comparatively better properties in terms of its smell, pH, calorific value, and absence of environmentally undesirable compounds. However, future works should include ASTM 6751 specifications tests for biodiesel to evaluate the bio-oil's suitability for commercial use.
Journal of environmental chemical engineering, Mar 1, 2014
Sago or Metroxylon sagu, harvested in Sarawak, Malaysia, is a low-cost, natural adsorbent. The sa... more Sago or Metroxylon sagu, harvested in Sarawak, Malaysia, is a low-cost, natural adsorbent. The sago bark (SB) from M. sagu was investigated for adsorptive removal of emulsified oil in palm oil mill effluent (POME). Hydrophobicity of this sorbent in aqueous state was improved via esterification process. The esterification of SB was conducted at ratio of sago bark to stearic acid (SA) by 1:1, 4:1, and 7:1; percentage catalyst of 5, 10, and 15; and refluxing time 1, 4.5, and 8 h; respectively. These parameters were analysed using full central composite design (CCD) of response surface methodology (RSM). The adjusted R-squared value of 0.9509 showed that the regression model fit the data well. The predicted R-squared value (0.9168) also indicated that the prediction of experimental data was satisfactory. Hydrophobicity test, FTIR, and SEM were carried out to characterise the esterified sago bark (ESB). Results showed that esterification process successfully increased the hydrophobicity of sago bark by 42.2% and oil removal efficiency in POME by 50.2%. A developed twofactor interaction (2FI) model showed that the preparation conditions of 1:1 SB:SA, 15% catalyst, and 8 h refluxing time afforded ESB with the maximum oil removal efficiency of up to 95.52% in POME. The esterification of SB successfully improved the oil adsorptivity for the removal of emulsified oil in POME.
Fuel Processing Technology, Feb 1, 2013
Pyrolysis of palm kernel shell (PK), wood chips (WC) and sago wastes (SW) was performed on microw... more Pyrolysis of palm kernel shell (PK), wood chips (WC) and sago wastes (SW) was performed on microwave irradiation at different heating time, at moderate temperature 250-390°C. Samples were placed in quartz reactor and subjected to microwave heating in inert atmosphere to afford bio-oils (PKO, WCO and SWO). The highest calorific values recorded are 27.19 MJ/kg, 25.99 MJ/kg, and 21.99 MJ/kg for PKO, WCO and SWO. FTIR spectroscopy showed the presence of functional groups such as phenol, alcohols, ketones, aldehydes and carboxylic acids. The GCMS showed that PKO, WCO and SWO consist of significant quantities of potentially high value hydrocarbons such as monoaromatic hydrocarbons and phenolic compounds. Importantly, the bio-oils do not contain carcinogenic polyaromatic hydrocarbons (PAH). Upon further refining, the bio-oils have a potential as valuable source for fuel or chemical feedstocks.
Biochar production from agricultural wastes via low temperature microwave pyrolysis is discussed ... more Biochar production from agricultural wastes via low temperature microwave pyrolysis is discussed in the present work as an alternative to the time and energy consuming conventional carbonization. The characteristics of biochar produced from palm kernel shell (PKC), wood chips (WCC) and sago waste (SWC) produced from microwave pyrolysis were investigated. The maximum calorific value of PKC, WCC and SWC in this study was 29.04, 24.89 and 25.99 MJ/kg respectively. FTIR analysis reveals that the biochars contain O-H, C-H and C=C functional groups, while the SEM analysis showed the formation of porous structure of biochars carbonized at lower temperature for all samples. Results indicated the potential use of these biochar as fuel material and precursor for activated carbon.
Polycyclic Aromatic Compounds, Jun 21, 2021
oxoprop-1-enyl) benzoic acid (1a) 4-Iodoacetophenone (0.246 g, 0.001 mol) was used to achieve (1a... more oxoprop-1-enyl) benzoic acid (1a) 4-Iodoacetophenone (0.246 g, 0.001 mol) was used to achieve (1a) (0.261 g, 68.72 %) as
Malaysian Journal of Fundamental and Applied Sciences, Jun 21, 2014
A synthesis of a new type of chalcone analogue banana-shaped liquid crystals compounds is describ... more A synthesis of a new type of chalcone analogue banana-shaped liquid crystals compounds is described. The approach involved the reaction of hydroxyl chalcones with isophthaloyl dichloride to form benzene-1,3-dicarbonyl-bis-1-(4-alkoxyphenyl)-3-(4-hydroxylphenyl)prop-2-en-1-one (7a-c and 8a-c) having two chalcone units via esterification reaction. The hydroxyl chalcones, which differ in the length of alkyl group, CnH2n+1, where n= 10, 12 and 14 were synthesised via Claisen Schmidt condensation prior to the reaction with isophthaloyl dichloride. The reaction was a catalyst dependence. No sign of product was formed by employing NaH (60%). It was only occurred in the presence of NaH (95%) to afford banana shape bi-functional monomer of ester chalcone 7a-c and 8a-c. The synthesized compound was characterized by 1 H and 13 C Nuclear Magnetic Resonance (NMR), and Fourier Transform Infrared (FTIR).
Functionalized Graphene Nanocomposites for Water Treatment
Elsevier eBooks, 2019
Abstract Graphene is 2-D structure of a single-atom-thick sheet of sp2-hybridized carbon atoms ar... more Abstract Graphene is 2-D structure of a single-atom-thick sheet of sp2-hybridized carbon atoms arrayed in a honeycomb pattern with a bond length of 0.141 nm. It is undoubtedly the most intensively studied material with extraordinary properties that are even more promising than other nanostructured carbon allotropes. It is the thinnest, strongest, and stiffest material, with large specific surface area and good chemical stability, is an excellent conductor of both heat and electricity, and also has other superior characteristics of electronic, mechanical, optical, and transport natures. Graphene, with such specific properties, holds great promise for the removal of pollutants from water through adsorption and photocatalytic degradation. The strong π–π stacking interactions in graphene result in cluster formation, which is not conducive for the adsorption of pollutants. Overcoming this limitation functionalization of graphene has been done via covalent and noncovalent interactions.
Journal of Chemistry, 2017
In this study, hexasubstituted thiourea was carried out via reaction of isothiocyanato cyclophosp... more In this study, hexasubstituted thiourea was carried out via reaction of isothiocyanato cyclophosphazene intermediates with a series of aromatics amines and amino acids in a one-pot reaction system. The reaction was not as straightforward as typical thiourea synthesis. Six unexpected thiourea derivatives a-f were formed in the presence of cyclotriphosphazene moieties in good yields (53-82%). The structures of a-f were characterized by elemental analysis and FTIR, 1 H, 13 C, and 31 P NMR spectroscopies. The occurrence of reverse thioureas formation in a one-pot reaction system is discussed. The possible binding interaction of the synthesised thiourea a-b in comparison to the predicted phenyl thiourea a-b and the targeted a with enzyme enoyl ACP reductase (FabI) is also discussed. Molecular docking of the targeted hexasubstituted thiourea a is able to give higher binding affinity of −7.5 kcal/mol compared to a-b (−5.9 kcal/mol and −6.3 kcal/mol) and thiourea a-b (−4.5 kcal/mol and −4.7 Kcal/mol).
Chemistry Africa, Nov 23, 2020
Coronavirus disease 2019 (COVID-19) has become a global pandemic in a short period, where a tragi... more Coronavirus disease 2019 (COVID-19) has become a global pandemic in a short period, where a tragically large number of human lives being lost. It is an infectious pandemic that recently infected more than two hundred countries in the world. Many potential treatments have been introduced, which are considered potent antiviral drugs and commonly reported as herbal or traditional and medicinal treatments. A variety of bioactive metabolites extracts from natural herbal have been reported for coronaviruses with some effective results. Food and Drug Administration (FDA) has approved numerous drugs to be introduced against COVID-19, which commercially available as antiviral drugs and vaccines. In this study, a comprehensive review is discussed on the potential antiviral remedies based on natural and synthetic drugs. This review highlighted the potential remedies of COVID-19 which successfully applied to patients with high cytopathic inhibition potency for cell-tocell spread and replication of coronavirus.
Current Chemical Biology, Jan 18, 2021
Background: Sago palm is an important agricultural starch-producing crop in Malaysia. The trunk o... more Background: Sago palm is an important agricultural starch-producing crop in Malaysia. The trunk of sago palm is responsible for the the starch to reach maturity for harvesting after ten years. However, there are sago palms that fail to develop thier trunk after 17 years of being planted. This is known as a stressed "non-trunking" sago palm, which reduces the economic value of the palms. Objective: The study was initiated to compare the differences in metabolite expression between trunking and non-trunking sago palms and secondly to determine the potential metabolite-makers that are related to differential phenotypes of sago palms. Methods: Metabolites were extracted using various solvents and analysed using NMR spectroscopy and GC-MS spectrometry. Data obtained were subjected to principal component analysis. Results: The study determined differential metabolites expression in the leaf extracts of normal trunking sago palm compared to the non-trunking palms. Metabolite groups differently expressed between trunking and non-trunking sago palm are oils and waxes, haloalkanes, sulfite esters, phosphonates, phosphoric acid, thiophene ester, terpenes and tocopherols. GC-MS analysis of Jones & Kinghorn extraction method determined two sets of metabolite markers, explaining the differences in metabolites expression of trunking and nontrunking sago palms in ethyl acetate and methanol extract of 89.55% comprising sulfurous ester compounds and 87.04% comprising sulfurous ester, sulfurous acid and cyclohexylmethyl hexyl ester, respectively. Conclusion: Two sets of metabolite markers were expressed in the trunking and nontrunking sago palms. These metabolites can potentially be used as markers for identifying normal and stressed plants.
Materials Today: Proceedings, 2019
In present work, reduced graphene oxide (rGO) thin films was produced by using modified hydrazine... more In present work, reduced graphene oxide (rGO) thin films was produced by using modified hydrazine vapor. The experiment was conducted by varying the reduction temperatures to 50 ˚C, 60 ˚C, 70 ˚C and 80 ˚C respectively. This work's aim is to investigate the effect of reduced temperature on the properties of rGO thin films. The thin films were characterized by using Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR). Meanwhile, the electrical studies was performed by using current-voltage (I-V) characteristic. The electrical conductivity had increased from 2.35x10-5 S/cm to 1.04x10-4 S/cm as the temperature increases from 50 ˚C-70 ˚C. On the other hand, as the temperature reaches 80 ˚C, the electrical conductivity decreased to 6.49x10-5 S/cm due to the defect that occurs at higher temperature. The morphological, and optical data also confirms that the properties of rGO is affected by the reduction temperature tested. Optimized rGO thin films can potentially be applied to electrical and electronic applications.
Synthesis of Fluorescent Nanosensor for Biomedical Engineering
CRC Press eBooks, Jan 23, 2023
Synthesis and structure–activity relationship studies of mono- and bis-thiourea derivatives featuring halogenated azo dyes with antimicrobial properties
Phosphorus Sulfur and Silicon and The Related Elements, Mar 7, 2022
![Research paper thumbnail of (<i>E</i>)-1-(3-Hydroxyphenyl)-3-[4-(tetradecyloxy)phenyl]prop-2-en-1-one](https://attachments.academia-assets.com/118550620/thumbnails/1.jpg)
](Acta Crystallographica Section E-structure Reports Online, Sep 8, 2012
In the title compound, C 29 H 40 O 3 , the enone moiety adopts an s-cis conformation. The dihedra... more In the title compound, C 29 H 40 O 3 , the enone moiety adopts an s-cis conformation. The dihedral angle between the benzene rings is 4.33 (5) The least-squares mean line through the tetradecyl side chain forms a dihedral angle of 83.99 (7) with the normal to the attached benzene ring. In the crystal, O-HÁ Á ÁO and C-HÁ Á ÁO hydrogen bonds involving the keto and the hydroxy O atoms form ribbons along [411]. The crystal structure also features C-HÁ Á Á interactions.
![Research paper thumbnail of (<i>E</i>)-1-[4-(Hexyloxy)phenyl]-3-(2-hydroxyphenyl)prop-2-en-1-one](https://attachments.academia-assets.com/118550626/thumbnails/1.jpg)
](Acta Crystallographica Section E-structure Reports Online, Sep 8, 2012
Journal of Forensic Sciences, Aug 10, 2015
Paraquat poisoning is commonly associated with suicide or homicide in Malaysia. In a case involvi... more Paraquat poisoning is commonly associated with suicide or homicide in Malaysia. In a case involving advanced body decomposition, pathological analysis regarding the cause of death may become difficult or almost impossible. Insects serve as common alternative matrix for poison detection in forensic analysis. Paraquat detection via secondary bioaccumulation in fly larvae tissue has never been reported. In this study, tissues from blowfly larvae collected from a rabbit carcass with paraquat poisoning were analyzed for secondary bioaccumulation. Larvae samples were collected and analyzed using liquid-liquid extraction. The detection was performed via reduction of quaternary ammonium presence in paraquat and analyzed using gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring mode (SIM mode). GC-MS showed the elution of reduced paraquat was at retention time 12.8 min. Blowfly larvae tissue has proven useful as a secondary detector in paraquat-related deaths.
Elsevier eBooks, 2021
Knowledge and best practice in this field are constantly changing. As new research and experience... more Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary.
Malaysian Journal of Fundamental and Applied Sciences, Jul 24, 2014
The reactions of 3,4,6-tri-O-acetyl-D-glucal with phenolic and aliphatic alcohol in various Lewis... more The reactions of 3,4,6-tri-O-acetyl-D-glucal with phenolic and aliphatic alcohol in various Lewis acid catalysts (namely La(NO3)3.6H2O, InCl3, ZnCl2 and BF3•OEt2) have furnished the corresponding alkyl and aryl 2,3-unsaturated glycopyranosides via Ferrier rearrangement. BF3•OEt2 showed the best Lewis acids catalysts with excellent yields and minimum reaction times. The reactions performed in CH3CN gave better yields and shorter reaction times compared to CH2Cl2. The electron withdrawing properties of aromatic ring resulting lower yields of aryl 2,3-unsaturated glycopyranosides compared to alkyl 2,3-unsaturated glycopyranosides under this condition. This study is significant in the preparation of O-glycosides via Ferrier rearrangement.
Waste and Biomass Valorization, Mar 23, 2019
In this study, microwave induced pyrolytic oil from sago bark (SB) was subjected to esterificatio... more In this study, microwave induced pyrolytic oil from sago bark (SB) was subjected to esterification to improve its properties. Improvement on properties of the pyrolytic oil was performed via esterification with ethanol and the presence of sulfuric acid as a catalyst. The optimum esterification condition was studied using general factorial design. The esterified oil (EO) showed improved properties with pH (4-6), reduced moisture content (2.95-3.45%), density (0.9-1.1 g cm −3), and acid value (39.3-123.4 mg KOH −1 g −1), and maintained the CV (20.2-21.6 MJ kg −1). GC-MS analysis showed that EO was sulphur free, and low in carboxylic acid and oxygenated compounds. The optimal esterification condition with optimum quality of EO was at 65 °C temperature, 60 min reaction time and 1:1 ethanol to oil volume ratio. Results indicated that the EO can be potentially used in robust combustion engines upon properties refinement.
Environmental Science and Pollution Research, May 31, 2019
Sago bark (SB) and empty fruit bunch (EFB) are available abundantly as agricultural waste in Sara... more Sago bark (SB) and empty fruit bunch (EFB) are available abundantly as agricultural waste in Sarawak. This study was conducted to investigate the physicochemical characteristics of SB and EFB as composting materials and used as a plant growth medium. The SB and EFB composts were prepared in a separate container by mixing chicken manure as compost accelerator and wood chips as a bulking agent in dry weight equivalent ratio (1:1:1). The maturity and stability of compost in 60-day composting periods were evaluated via physicochemical characterization of the composts in terms of pH, elemental content, total ash content, moisture content and nutrient analyses. The effect of the compost usage as growth medium was assessed towards water spinach and green mustard via seed germination and pot study. After 2 months, the colour of both composts was dark brown with an earthy smell. The acidic pH of the initial composting stage has changed into alkaline pH after 60 days of composting. Total NPK present in the SB and EFB composts were 0.96% and 1.21%, respectively. The germination index (GI) for the studied vegetables was above 100%, while the pot study showed that vegetables in compost media has higher growth compared to the control, after 14 days. SB and EFB are renewable waste which can be used as an excellent compost and able to improve the quality of the soil.
Journal of Chemistry, 2017
Microwave pyrolysis is a potential for producing alternative fuel from biomass, such as palm kern... more Microwave pyrolysis is a potential for producing alternative fuel from biomass, such as palm kernel shell (PKS). However, the resulting microwave pyrolytic oil (bio-oil) was highly acidic and has low calorific value and therefore must undergo additional process to improve the physicochemical properties. In this study, attempt was made to improve the pH and calorific value of bio-oil produced from PKS via esterification process. The effect of esterification with ethanol in the presence of sulphuric acid as a catalyst on selected biodiesel qualities was also investigated. The esterification process has successfully improved the pH value from 3.37 to 5.09-5.12 and the calorific value was increased from 27.19 to 34.78-41.52 MJ/kg. Conclusively, the EO has comparatively better properties in terms of its smell, pH, calorific value, and absence of environmentally undesirable compounds. However, future works should include ASTM 6751 specifications tests for biodiesel to evaluate the bio-oil's suitability for commercial use.
Journal of environmental chemical engineering, Mar 1, 2014
Sago or Metroxylon sagu, harvested in Sarawak, Malaysia, is a low-cost, natural adsorbent. The sa... more Sago or Metroxylon sagu, harvested in Sarawak, Malaysia, is a low-cost, natural adsorbent. The sago bark (SB) from M. sagu was investigated for adsorptive removal of emulsified oil in palm oil mill effluent (POME). Hydrophobicity of this sorbent in aqueous state was improved via esterification process. The esterification of SB was conducted at ratio of sago bark to stearic acid (SA) by 1:1, 4:1, and 7:1; percentage catalyst of 5, 10, and 15; and refluxing time 1, 4.5, and 8 h; respectively. These parameters were analysed using full central composite design (CCD) of response surface methodology (RSM). The adjusted R-squared value of 0.9509 showed that the regression model fit the data well. The predicted R-squared value (0.9168) also indicated that the prediction of experimental data was satisfactory. Hydrophobicity test, FTIR, and SEM were carried out to characterise the esterified sago bark (ESB). Results showed that esterification process successfully increased the hydrophobicity of sago bark by 42.2% and oil removal efficiency in POME by 50.2%. A developed twofactor interaction (2FI) model showed that the preparation conditions of 1:1 SB:SA, 15% catalyst, and 8 h refluxing time afforded ESB with the maximum oil removal efficiency of up to 95.52% in POME. The esterification of SB successfully improved the oil adsorptivity for the removal of emulsified oil in POME.
Fuel Processing Technology, Feb 1, 2013
Pyrolysis of palm kernel shell (PK), wood chips (WC) and sago wastes (SW) was performed on microw... more Pyrolysis of palm kernel shell (PK), wood chips (WC) and sago wastes (SW) was performed on microwave irradiation at different heating time, at moderate temperature 250-390°C. Samples were placed in quartz reactor and subjected to microwave heating in inert atmosphere to afford bio-oils (PKO, WCO and SWO). The highest calorific values recorded are 27.19 MJ/kg, 25.99 MJ/kg, and 21.99 MJ/kg for PKO, WCO and SWO. FTIR spectroscopy showed the presence of functional groups such as phenol, alcohols, ketones, aldehydes and carboxylic acids. The GCMS showed that PKO, WCO and SWO consist of significant quantities of potentially high value hydrocarbons such as monoaromatic hydrocarbons and phenolic compounds. Importantly, the bio-oils do not contain carcinogenic polyaromatic hydrocarbons (PAH). Upon further refining, the bio-oils have a potential as valuable source for fuel or chemical feedstocks.
Biochar production from agricultural wastes via low temperature microwave pyrolysis is discussed ... more Biochar production from agricultural wastes via low temperature microwave pyrolysis is discussed in the present work as an alternative to the time and energy consuming conventional carbonization. The characteristics of biochar produced from palm kernel shell (PKC), wood chips (WCC) and sago waste (SWC) produced from microwave pyrolysis were investigated. The maximum calorific value of PKC, WCC and SWC in this study was 29.04, 24.89 and 25.99 MJ/kg respectively. FTIR analysis reveals that the biochars contain O-H, C-H and C=C functional groups, while the SEM analysis showed the formation of porous structure of biochars carbonized at lower temperature for all samples. Results indicated the potential use of these biochar as fuel material and precursor for activated carbon.
Polycyclic Aromatic Compounds, Jun 21, 2021
oxoprop-1-enyl) benzoic acid (1a) 4-Iodoacetophenone (0.246 g, 0.001 mol) was used to achieve (1a... more oxoprop-1-enyl) benzoic acid (1a) 4-Iodoacetophenone (0.246 g, 0.001 mol) was used to achieve (1a) (0.261 g, 68.72 %) as
Malaysian Journal of Fundamental and Applied Sciences, Jun 21, 2014
A synthesis of a new type of chalcone analogue banana-shaped liquid crystals compounds is describ... more A synthesis of a new type of chalcone analogue banana-shaped liquid crystals compounds is described. The approach involved the reaction of hydroxyl chalcones with isophthaloyl dichloride to form benzene-1,3-dicarbonyl-bis-1-(4-alkoxyphenyl)-3-(4-hydroxylphenyl)prop-2-en-1-one (7a-c and 8a-c) having two chalcone units via esterification reaction. The hydroxyl chalcones, which differ in the length of alkyl group, CnH2n+1, where n= 10, 12 and 14 were synthesised via Claisen Schmidt condensation prior to the reaction with isophthaloyl dichloride. The reaction was a catalyst dependence. No sign of product was formed by employing NaH (60%). It was only occurred in the presence of NaH (95%) to afford banana shape bi-functional monomer of ester chalcone 7a-c and 8a-c. The synthesized compound was characterized by 1 H and 13 C Nuclear Magnetic Resonance (NMR), and Fourier Transform Infrared (FTIR).
Functionalized Graphene Nanocomposites for Water Treatment
Elsevier eBooks, 2019
Abstract Graphene is 2-D structure of a single-atom-thick sheet of sp2-hybridized carbon atoms ar... more Abstract Graphene is 2-D structure of a single-atom-thick sheet of sp2-hybridized carbon atoms arrayed in a honeycomb pattern with a bond length of 0.141 nm. It is undoubtedly the most intensively studied material with extraordinary properties that are even more promising than other nanostructured carbon allotropes. It is the thinnest, strongest, and stiffest material, with large specific surface area and good chemical stability, is an excellent conductor of both heat and electricity, and also has other superior characteristics of electronic, mechanical, optical, and transport natures. Graphene, with such specific properties, holds great promise for the removal of pollutants from water through adsorption and photocatalytic degradation. The strong π–π stacking interactions in graphene result in cluster formation, which is not conducive for the adsorption of pollutants. Overcoming this limitation functionalization of graphene has been done via covalent and noncovalent interactions.
Journal of Chemistry, 2017
In this study, hexasubstituted thiourea was carried out via reaction of isothiocyanato cyclophosp... more In this study, hexasubstituted thiourea was carried out via reaction of isothiocyanato cyclophosphazene intermediates with a series of aromatics amines and amino acids in a one-pot reaction system. The reaction was not as straightforward as typical thiourea synthesis. Six unexpected thiourea derivatives a-f were formed in the presence of cyclotriphosphazene moieties in good yields (53-82%). The structures of a-f were characterized by elemental analysis and FTIR, 1 H, 13 C, and 31 P NMR spectroscopies. The occurrence of reverse thioureas formation in a one-pot reaction system is discussed. The possible binding interaction of the synthesised thiourea a-b in comparison to the predicted phenyl thiourea a-b and the targeted a with enzyme enoyl ACP reductase (FabI) is also discussed. Molecular docking of the targeted hexasubstituted thiourea a is able to give higher binding affinity of −7.5 kcal/mol compared to a-b (−5.9 kcal/mol and −6.3 kcal/mol) and thiourea a-b (−4.5 kcal/mol and −4.7 Kcal/mol).
Chemistry Africa, Nov 23, 2020
Coronavirus disease 2019 (COVID-19) has become a global pandemic in a short period, where a tragi... more Coronavirus disease 2019 (COVID-19) has become a global pandemic in a short period, where a tragically large number of human lives being lost. It is an infectious pandemic that recently infected more than two hundred countries in the world. Many potential treatments have been introduced, which are considered potent antiviral drugs and commonly reported as herbal or traditional and medicinal treatments. A variety of bioactive metabolites extracts from natural herbal have been reported for coronaviruses with some effective results. Food and Drug Administration (FDA) has approved numerous drugs to be introduced against COVID-19, which commercially available as antiviral drugs and vaccines. In this study, a comprehensive review is discussed on the potential antiviral remedies based on natural and synthetic drugs. This review highlighted the potential remedies of COVID-19 which successfully applied to patients with high cytopathic inhibition potency for cell-tocell spread and replication of coronavirus.
Current Chemical Biology, Jan 18, 2021
Background: Sago palm is an important agricultural starch-producing crop in Malaysia. The trunk o... more Background: Sago palm is an important agricultural starch-producing crop in Malaysia. The trunk of sago palm is responsible for the the starch to reach maturity for harvesting after ten years. However, there are sago palms that fail to develop thier trunk after 17 years of being planted. This is known as a stressed "non-trunking" sago palm, which reduces the economic value of the palms. Objective: The study was initiated to compare the differences in metabolite expression between trunking and non-trunking sago palms and secondly to determine the potential metabolite-makers that are related to differential phenotypes of sago palms. Methods: Metabolites were extracted using various solvents and analysed using NMR spectroscopy and GC-MS spectrometry. Data obtained were subjected to principal component analysis. Results: The study determined differential metabolites expression in the leaf extracts of normal trunking sago palm compared to the non-trunking palms. Metabolite groups differently expressed between trunking and non-trunking sago palm are oils and waxes, haloalkanes, sulfite esters, phosphonates, phosphoric acid, thiophene ester, terpenes and tocopherols. GC-MS analysis of Jones & Kinghorn extraction method determined two sets of metabolite markers, explaining the differences in metabolites expression of trunking and nontrunking sago palms in ethyl acetate and methanol extract of 89.55% comprising sulfurous ester compounds and 87.04% comprising sulfurous ester, sulfurous acid and cyclohexylmethyl hexyl ester, respectively. Conclusion: Two sets of metabolite markers were expressed in the trunking and nontrunking sago palms. These metabolites can potentially be used as markers for identifying normal and stressed plants.
Materials Today: Proceedings, 2019
In present work, reduced graphene oxide (rGO) thin films was produced by using modified hydrazine... more In present work, reduced graphene oxide (rGO) thin films was produced by using modified hydrazine vapor. The experiment was conducted by varying the reduction temperatures to 50 ˚C, 60 ˚C, 70 ˚C and 80 ˚C respectively. This work's aim is to investigate the effect of reduced temperature on the properties of rGO thin films. The thin films were characterized by using Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR). Meanwhile, the electrical studies was performed by using current-voltage (I-V) characteristic. The electrical conductivity had increased from 2.35x10-5 S/cm to 1.04x10-4 S/cm as the temperature increases from 50 ˚C-70 ˚C. On the other hand, as the temperature reaches 80 ˚C, the electrical conductivity decreased to 6.49x10-5 S/cm due to the defect that occurs at higher temperature. The morphological, and optical data also confirms that the properties of rGO is affected by the reduction temperature tested. Optimized rGO thin films can potentially be applied to electrical and electronic applications.
Synthesis of Fluorescent Nanosensor for Biomedical Engineering
CRC Press eBooks, Jan 23, 2023
Synthesis and structure–activity relationship studies of mono- and bis-thiourea derivatives featuring halogenated azo dyes with antimicrobial properties
Phosphorus Sulfur and Silicon and The Related Elements, Mar 7, 2022
Acta Crystallographica Section E-structure Reports Online, Sep 8, 2012
In the title compound, C 29 H 40 O 3 , the enone moiety adopts an s-cis conformation. The dihedra... more In the title compound, C 29 H 40 O 3 , the enone moiety adopts an s-cis conformation. The dihedral angle between the benzene rings is 4.33 (5) The least-squares mean line through the tetradecyl side chain forms a dihedral angle of 83.99 (7) with the normal to the attached benzene ring. In the crystal, O-HÁ Á ÁO and C-HÁ Á ÁO hydrogen bonds involving the keto and the hydroxy O atoms form ribbons along [411]. The crystal structure also features C-HÁ Á Á interactions.
Acta Crystallographica Section E-structure Reports Online, Sep 8, 2012