Pusat Pengajian Sains Kimia - Tesis

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Sintesis Dan Pencirian Polimer-polimer Terbitan Daripada Getah Asli 50%-Terepoksida Dan Natrium 1,3,3,5,5, -Pentakis(Trifluoroetoksi) -1-Oksosiklotrifosfazenat
(1993-04)
Loo Swee Chow
Getah asli SO%-terepoksida (ENR-SO) telah ditindakbalaskan dengan natrium 1,3,3,S,S-pentakis(trifluoroetoksi)-1-oksosiklotrifosfazenat (mononatrium fosfazenat) dalam 1,4- dioksana refluks. Polimer-polimer terbitan yang diperolehi daripada nisbah berat ENR-SO:mononatrium fosfazenat yang berlainan (1.00:0.50, 1.00:1.00, 1.00:2.00, 1.00:3.00, 1.00: 4.50 dan 1.00:5.50) didapati mempunyai nilai-nilai suhu peralihan kaca (Tg) yang lebih tinggi daripada nilai Tg ENR- 50. Walau bagaimanapun, kesemua polimer terbitan didapati larut dalam 1,4-dioksana, tetrahidrofuran dan etanol.
Towards a Knowledge Base for Network Diagnosis
(1994-05)
Gregory, N. Vincent
In this dissertation, the domain knowledge analyzed and current techniques in troubleshooting and current expert systems in the network domain are examined. A model that will be arguably most suited for the network domain is proposed and a prototype system that will be capable of diagnosing today's complex network components is presented.
Pengolahan Air Buangan Pencelup Melalui Penambahan Serbuk Karbon Diaktifkan Ke Dalam Enapan Teraktif Dalam Reaktor Kelompok Berturutan
(1998-02)
Er Cheow Chin
Penyelidikan ini bertujuan untuk mengkaji pengolahan air buangan berpencelup Biru Asid dan Kuning Bes dengan sistem PACT berlangkah SBRT. Lima jenis bahan penjerap iaitu serbuk karbon diaktifkan (PAC), tanah gambut, abuk kayu, sekam padi dan biomas telah diselidik dari segi kecekapan penyingkiran terhadap kedua-dua pencelup Biru Asid dan Kuning Bes.
Docking And Molecular Dynamics Simulation Studies Of Insulin-P- Cyclodextrin Interactions
(2016-02)
Muhammad, Erma Fatiha
Protein-ligand interactions play an essential role in the design of new pharmaceutical products. This study attempts to understand the theoretical basis on the structure and dynamics of insulin-cyclodextrin complex for new oral insulin formulation. Docking and molecular dynamics simulations explore the interactions between insulin monomer and insulin dimer with 0- cyclodextrins (0-CDs). A multiple molecular docking study was performed using the Autodock v4.2 program to determine the number of 0-CD that can adhere to the binding sites of insulin as well as to determine the most stable conformations of insulin to p-CDs. A 100 random structure docking using 1:1 insulin monomer-P-CD and insulin dimer-p-CD ratio were conducted and from the final docked structure, additional 0-CDs were added and the process were repeated until the energy increase. Molecular docking results revealed that a maximum of four 0-CDs can bind to an insulin structure with the 1:3 insulin-P-CD ratios having the lowest binding free energy. A 100 ns molecular dynamics simulation was then conducted to verify the results obtained by molecular docking.
Species Composition And Spatial Variation Of Benthic Diatoms At Intertidal Zone Under The Influence Of Environmental Parameters
(2017-12)
Ahmad Nordin, Noor Alia
Benthic diatoms play a significant role in the primary productivity and sediment dynamics of coastal and estuarine intertidal ecosystems. Thus, this study aims to determine the spatial distribution of benthic diatoms in intertidal flats from different environmental gradients. The spatial changes of benthic diatom composition under the influence of environmental variables in the tidal flats were studied. Canonical Correspondence Analysis (CCA) was conducted to define the relationships between environmental variables and diatom communities. Sediment samples were collected during low tide at six sampling stations four times in November 2013, February 2014, July 2014 and December 2014 in the coastal area of Tanjung Bungah, and in August 2014, January 2015, May 2015 and September 2015 in Tanjung Rhu, Langkawi estuary.
Design, Synthesis, Molecular Docking And Cytotoxic Activity Of New Ortho-Hydroxy Chalcone And Pyrazoline Derivatives
(2019-06)
Luhaibi, Maadh Jumaah Owaid
This study focused on the design and synthesis of new compounds with anticancer activity. The compounds were constructed using the structure-based drug design, focusing on their binding capabilities to the Colchicine (PDB code: IS AO) active site in a bidentate manner, with the most energetically preferable binding modes using Autodock Vina 1.1.2 and Discovery studio 4.1. In the molecular docking analysis, the binding energy and interactions between protein receptors and ligands provide a better understanding of the biological functions to determine the amino acid residues which are crucial to docking interactions. The modification and replacement of the pyrazoline structure and chaicone led to the development of the structureactivity relationship and identified potent and selective inhibitors of drug design.
Transesterification Of Palm Cooking Oil Using BiFeO3 Nanocatalyst
(2019-08)
Razuki, Nor Amirah
A novel heterogeneous bismuth ferrite nanocatalyst was successfully synthesized via facile biotemplated technique (BiFeO3) using polysaccharides of kappa-carrageenan with an aim to study its efficiency transesterification reaction of palm cooking oil. Pure BiFeO3 with particle size of 95.8 nm was obtained using 1:2 molar ratio of Bi to Fe with 1 % carrageenan biotemplate and calcined at 823 K for 2 hours. The produced nanocatalyst possess high thermal stability and X-ray diffraction (XRD) result confirmed the purity of its rhombohedral crystalline phases.
Synthesis And Characterization Of 1,3- Disubstituted Benzimidazolium Salts And Silver(I)-7v-Heterocyclic Carbene Complexes As Potential Ionic Liquid Crystals And Antibacterial Agents
(2019-08)
Yeap, Choon Wan
This work involved the synthesis and characterization of 1,3-disubstituted benzimidazolium salts and their silver(I)-NHC complexes via A-alkylation method and silver base route. The results from Fourier-transform Infrared spectroscopy (FTIR), ‘H-NMR, 13C-NMR spectroscopy and CHN elemental analysis have revealed that the 1,3-disubstituted benzimidazolium salts and their silver(I)-NHC complexes were successfully prepared.
Natural Rubber And Natural Rubber Grafted Chitosan Films For Removal Of Dyes
(2019-08)
Hasanuddin, Nurul Hasliza
In this study, adsorption experiments of methylene blue (MB) onto the surface of natural rubber (NR) were accomplished under optimized conditions of initial dye concentration, pH and temperature. The adsorption process of MB onto NR in the concentrations range from 3.2 mg L’1 — 16.0 mg L"1 were found to follow linearized pseudo 2nd order: Type 1. The adsorption isotherm of NR onto MB obeyed the Langmuir isotherm with an agreement of R2= 0.9750. The calculated values of AH, AS, AG and Ea were found to be -21732.58 J mol’1, +14.24 J K‘* mol and - 26047.30 J mol'1 and +23.71 kJ mol'1 respectively. This adsorption study was shown to be spontaneous and exothermic in nature. However, NR took days to adsorb MB and failed to adsorb methyl orange (MO). Thus NR grafted chitosan (NR-g-Chi) with varied ratios of 80:20, 75:25 and 70:30 were implemented to improve the adsorption performance. The unpurified and purified NR-g-Chi was characterized using FTIR, TGA and DSC. Both NR and NR-g-Chi were studied for their PZC and swelling behavior. The performance adsorption of MB using NR-g-Chi showed better results than NR adsorption itself with shorter time taken.
Interfacial enhancement of mixed matrix membrane using ionic liquid for co2 separation
(2020-04-10)
Ahmad, Nor Naimah Rosyadah
The use of mixed matrix membrane (MMM) appears to be a promising approach in CO2 separation application due to the synergistic effects of polymer and inorganic materials. However, poor compatibility between inorganic particles and polymer often results in interfacial defects that reduce the MMM gas separation performance. In this study, asymmetric MMMs comprises of polysulfone (PSf) and SAPO-34 zeolite were fabricated via dry-wet phase inversion. The loading of SAPO-34 zeolite in the MMM formulation was first varied from 5 to 15 wt.% to study the effect of zeolite loading to the characteristics of the MMMs and CO2 gas separation performance. Increasing the zeolite loading has enhanced the CO2 permeance of the MMM but reduced the CO2/N2 selectivity as compared to the neat PSf membrane. The incorporation of SAPO-34 zeolite in the PSf membrane has resulted in the voids formation at the polymer/filler interface contact as shown by scanning electron microscopy images. Ionic liquid (IL) which selective towards CO2 was used in this study to modify the MMM by sealing the interface defects in the membrane. Two different approaches namely premodification and post-modification were applied in the MMM modification. Results showed that the post-modification method with IL has improved both polymer/zeolite interface contact and gas separation performance of the MMM as compared to the premodification approach. The post-modification method was further explored by studying the effects of IL concentration, zeolite loading, solvent and IL properties. It was found that the post-modification of the MMM incorporated with 5 wt. % zeolite loading has enhanced the CO2/N2 selectivity about 820 % over the unmodified MMM by increasing the concentration of the IL/ethanol solution from 0.2 to 0.4 M. The CO2/N2 selectivity can also be increased when more polar solvent such as methanol was used in the post-modification of MMM involving low IL concentration (0.2 M). The CO2 permeance and CO2/N2 selectivity of IL-modified MMM was improved to 4.93-7.19 GPU and 26.63-35.21 respectively by using IL with large molecular weight since the reduction in zeolite porosity could be minimized. Analysis of the gas transport parameters revealed that the incorporation of IL into the MMM has increased the CO2 solubility of the membrane but the improvement in the CO2/N2 selectivity was mainly contributed by the diffusivity selectivity. The gas separation performance for the IL-modified MMM was observed to sustain when being exposed to the humid gas condition. Thus, the post-modification approach of MMM using IL can be as an alternative strategy in membrane development for CO2 separation application.
Nitrogen-Doped Biochar As Peroxymonosulfate Activator For Acid Orange 7 Removal
(2021-11)
Zaeni Julia Raudlatul Jannah
The first study shows the oxygen-functionalized biochar that obtained from biowaste through facile method is the promising catalyst as PMS activator and the second study provides insights into Ndoped biochar preparation with favourable intrinsic and extrinsic properties from biowaste for sustainable pollutant removal via PMS activation.
Synthesis, Characterization, And Photoluminescence Properties Of Ester Oligomers Containing Fluorene, Fluorescein And Curcumin Respectively For Potential Chemosensor Application
(2021-11)
Ong Hoay Ching
Three new homologous series of new ester oligomers containing fluorene (PF), fluorescein (FL) and curcumin (CM) on the backbone, respectively had been successfully synthesized and characterized. The molecular structures of the synthesized monomers and ester oligomers were elucidated by CHN, ATR-FTIR and FT-NMR (1D and 2D NMR). The synthesized ester oligomers showed high solubility in most of the common organic solvents, such as chloroform, tetrahydrofuran and acetone.
Comparative Analysis Of The Bioethanol Yield And Components Of Sugar Extracted From Oil Palm Frond Under Different Prehydrolysis Treatments
(2021-11)
Dissanayake Mudiyanselage Rushan Lakshitha Bonuwan Diyanilla
this study was designed to produce a high bioethanol yield from OPF adopting eco-friendly and viable pretreatment methods, which are acid, autohydrolysis, alkaline, alkaline peroxide, and alkaline peroxide pretreatment coupled with acidified sodium chlorite (ASC) pretreatment
Synthesis And Characterizations Of Biomass-Based Graphene Metal Oxide Anodes In Microbial Fuel Cells (MFCs) Applications
(2021-12)
Asim Ali Yaqoob
Microbial fuel cells (MFCs) ranked among the most promising bioelectrochemical approaches for generating electrical energy while removing pollutants from wastewater, however, their relatively poor performance, has limited their commercial viability. The fabrication of advanced electrode material for MFCs is the most potential topic at present to address the issue of low electron transfer rates in the MFCs operation. In the present work, green synthesized metal oxides (ZnO and TiO2) nanoparticles (NPs) were introduced to biomass-derived graphene oxide (GO) as nanocomposite anodes. The GO/metal oxide nanocomposite anodes provide efficient energy transfer and metal ions remediation. Several toxic metals such as lead, cadmium, chromium, nickel, cobalt, and mercury were targeted in the current study.
Development Of An Electrochemical Sensor Based On Molecularly Imprinted Go/Zno/Ppy Composites On Pencil Graphite Electrode For Determination Of Andrographolide
(2021-12)
Rabia Tasaduq Hussain
This research highlights the development of an electrochemical sensor based on graphene derivatives with a molecularly imprinted polypyyrole (PPy) layer on a pencil graphite electrode (PGE) to detect andrographolide, which is a bioactive component of an ancient plant known as Andrographis paniculata. Conventionally, andrographolide detection based on tedious and heavy instrumentation.
Preparation, Characterization, And Computational Study Of Bimetallic Iron Oxide Based Catalyst For Catalytic Oxidative Desulfurization Of Model Diesel
(2021-12)
Nor Atiq Syakila Binti Mohd Nazmi
Catalytic oxidative desulfurization (Cat-ODS) has been introduced as a new technique in achieving ultra-low sulfur diesel. In this study, Fe catalyst supported on alumina were prepared by wetness impregnation method and characterized using N2- adsorption/desorption (NA), field emission scanning electron microscopic (FESEM), X-ray diffraction (XRD) and High-Resolution Transmission Electron (HRTEM).
Electrochemical Degradation Of Reactive Red 4 Using Graphite/Chitosan-Poly(Vinyl Chloride) Composite Electrodes
(2021-12)
Nadhra Hidayah Binti Mohd Halim
In this study, graphite/chitosan-poly(vinyl chloride) (C/Chi-PVC) composite electrode was used as anode to investigate the degradation of Reactive Red 4 (RR4) in the presence of graphite rod and sodium chloride (NaCl) respectively as cathode and supporting electrolytes.
Synthesis Of Large Pore Zeolites For Catalyzing Furanic-Type Fuel Compounds
(2021-12)
Nur Hidayahni Binti Ahmad
Linde type L (LTL topology) and offretite (OFF topology) zeolites are large pore zeolites (diameter 7.1 × 7.1 Å2 and 6.7 × 6.8 Å2, respectively). The aim of this project is to synthesize and apply LTL and OFF acidic zeolites in catalyzing various furanic-type reactions
Preparation Of A Stabilized Nano-Lignin Emulsifier From Oil Palm Empty Fruit Bunch
(2022-01)
Siti Hajar Binti Sekeri
A study was carried out to determine the effectiveness of lignin, extracted from oil palm (Elaeis guineensis) biomass as a water-in-oil (W/O) emulsifier. To achieve this goal, soda lignin (SL) was extracted via soda pulping process and a series of nanosized soda lignin (NSL) was prepared using a homogenizer at three different speeds i.e., 10400 rpm (NSL 10), 11400 rpm (NSL 11), and 12400 rpm (NSL 12) for one hour.
Characterization, Kinetics And Equilibrium Studies Of Paracetamol Adsorption On The Oil Palm Fronds (Opf) Cellulose Nanocrystals
(2022-02)
Idris, Nor Najhan
Pollution of water via pharmaceutical drugs such as paracetamol have been a highly concerning issue; and effective measures must be taken to treat these aquatic contaminants. Hence, the present study explored use of cellulose nanocrystals (CNC) isolated from oil palm fronds (OPF) through pre-treatments and acid hydrolysis as an environmental friendly adsorbent. The complementary analyses showed that the OPF CNC possesses a crystallinity index of 43.60 %, surface area (10.51 m2 g-1), and an aspect ratio of 19.98. Besides, the OPF CNC and OPF CNC-AC hydrogel beads have been successfully produced, optimised, and applied for paracetamol removal. The modification of OPF CNC-AC hydrogel beads with the commercial activated carbon (AC) has improved the BET surface area up to 85.19 m2 g-1. The adsorption studies of paracetamol onto OPF CNC and OPF CNC-AC hydrogel beads can be achieved at 60 g and 0.6 g of adsorbent dosage, respectively, at a pH 3 with a contact time of 170 min under room temperature. It was observed that the produced data fitted best with the pseudo-second order kinetic model and Freundlich isotherm model for characterising the adsorption of paracetamol onto OPF CNC hydrogel beads with a maximum adsorption capacity, qmax of 0.03 mg g-1. Meanwhile, for OPF CNC-AC hydrogel beads, the pseudo-second order kinetic model and Langmuir isotherm model showed the best correlation for the adsorption of paracetamol with a qmax value of 21.31 mg g-1. Therefore, the output from this study may suggest that OPF CNC and OPF CNC- xxiv AC hydrogel beads can be used as natural adsorbents for the removal of paracetamol waste.

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