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2015

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Extractive Bioconversion Of Polycaprolactone By Lipase In Aqueous Two-Phase System / Chew Pey Ling, Pey Ling Chew Jan 2015

Extractive Bioconversion Of Polycaprolactone By Lipase In Aqueous Two-Phase System / Chew Pey Ling, Pey Ling Chew

Student Works (2010-2019)

Aqueous two-phase system (ATPS) is a technique used for recovery and purification of biomolecules. Extractive bioconversion is a system which integrates biotransformation into ATPS to allow the in situ recovery of bioproducts immediately after they are formed. The extractive bioconversion of poly-ε-caprolactone (PCL) in an ATPS had not been established. In addition, the properties of the products obtained following the extractive bioconversion process are not well understood. Therefore, this study aimed to determine the ideal conditions for Burkholderia cepacia lipase-mediated extractive bioconversion of PCL in a polyethylene glycol (PEG)-based ATPS, as well as to examine the properties of the products …

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Cloud Point Extraction Method For The Removal Of Phenolic Compounds From Water Samples Using Dc193c Non−Ionic Surfactant / Nur Nadhirah Mohamad Zain, Nur Nadhirah Mohamad Zain Jan 2015

Cloud Point Extraction Method For The Removal Of Phenolic Compounds From Water Samples Using Dc193c Non−Ionic Surfactant / Nur Nadhirah Mohamad Zain, Nur Nadhirah Mohamad Zain

Student Works (2010-2019)

A greener method based on cloud point extraction was optimized in three systems namely as cloud point extraction (CPE); CPE with β−cyclodextrin (CPE−βCD) and CPE with β−cyclodextrin functionalized with ionic liquids (CPE−βCD−IL) for removing phenolic compounds including 2,4−dichlorophenol (2,4−DCP), 2,4,6−trichlorophenol (2,4,6−TCP) and 4−nitrophenol (4−NP) in aqueous samples by using UV−Vis spectrophotometric technique. The DC193C surfactant was chosen as an extraction solvent due to its low water content in a surfactant rich phase. The parameters affecting the extraction efficiency such as pH, equilibration temperature and incubation time, concentration of surfactant, modifier, salt and analyte, volume of surfactant and modifier and water …

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Studies Of Breeding Habitats And Seasonal Occurrence Of Mosquitoes In Putrajaya And Kuala Selangor, With Laboratory Experiments Of Guppies And Dragonfly Nymphs As Potential Biocontrol Predators Against Mosquito Larvae / Siti Nurhafizah Saleeza Ramlee, Siti Nurhafizah Saleeza Ramlee Jan 2015

Studies Of Breeding Habitats And Seasonal Occurrence Of Mosquitoes In Putrajaya And Kuala Selangor, With Laboratory Experiments Of Guppies And Dragonfly Nymphs As Potential Biocontrol Predators Against Mosquito Larvae / Siti Nurhafizah Saleeza Ramlee, Siti Nurhafizah Saleeza Ramlee

Student Works (2010-2019)

Mosquito control is essential for the control of vector borne diseases. Many synthetic insecticides are widely used for controlling adult and larval mosquito populations. However, there are multirole effects: e.g. the harmful effects of chemicals on non-target organisms, the development of resistance to these chemicals in mosquitoes and the recent resurgence of different mosquito-borne diseases. The objectives of this study are to determine the potential breeding habitats of the mosquitoes, mosquito indices, mosquito species, density of mosquito larvae, perceptions of respondents on bio control and to conduct captivity studies on predator–prey relationships. Entomological surveillance was carried out in six localities …

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Computational Studies Of Glycolipids And Their Interactions With Carbon Nanotubes / Zahrabatoul Mosapour Kotena, Zahrabatoul Mosapour Kotena Jan 2015

Computational Studies Of Glycolipids And Their Interactions With Carbon Nanotubes / Zahrabatoul Mosapour Kotena, Zahrabatoul Mosapour Kotena

Student Works (2010-2019)

Carbon nanotubes (CNTs) have attracted the attention of many researchers due to their unique mechanical, structural, and electrical properties, and their apparent usefulness in nanotechnology, nanoelectronics, biosensors, biotechnology, biomedicine, and energy storage. Single-walled nanotubes (SWNTs) could be dispersed by surfactants, such as glycopyranoside, which is a family of non-ionic surfactants, from the more generic class of glycolipids found in nature, especially in biological membranes. Hydrogen bond is a dominant factor in different biological processes. This thesis focuses on the knowledge of the hydrogen bond formation in non-ionic surfactant such as glycolipids. Subsequently, we examined the effect of one of these …

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Isolation And Characterisation Of Metal-Tolerant Actinomycetes From A Karstic Cave In Malaysia / Yap Siew Mei, Siew Mei Yap Jan 2015

Isolation And Characterisation Of Metal-Tolerant Actinomycetes From A Karstic Cave In Malaysia / Yap Siew Mei, Siew Mei Yap

Student Works (2010-2019)

The main objective of this study was to isolate actinomycetes from environmental samples collected from the Dark Caves, a karstic cave located in Batu Caves, Kuala Lumpur, Malaysia. The environmental samples were collected from different parts of the cave including cave ceilings, columns, soils and stalagmites. Results showed the number of actinomycetes isolated from cave soils was the highest among all sampling sites, followed by cave wall, cave columns and the lowest was from stalagmite. A few types of isolation media were used to selectively isolate actinomycetes and the results showed higher percentage of total actinomycete isolates were obtained from …

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Synthesis, Characterization And Theoretical Study Of Amino Acid-Based Magnetic Molecularly Imprinted Polymer For Recognition Of Sulfonamide Drugs / Chen Lei, Lei Chen Jan 2015

Synthesis, Characterization And Theoretical Study Of Amino Acid-Based Magnetic Molecularly Imprinted Polymer For Recognition Of Sulfonamide Drugs / Chen Lei, Lei Chen

Student Works (2010-2019)

Sulfonamides antibiotics (SAs) are the oldest and among the most widely used antibacterial agent in the world. Due to its low cost and their relative efficacy in controlling some common bacterial related diseases, SAs have been widely used in various sectors. Since huge amount of SAs have been consumed every year, SAs have been released into the environment through various human activities. Among various classes of pharmaceutical, the presence of antibiotics in the environments has been one of the major concerns due to its ability to develop antibiotic-resistant bacteria. Thus, it is essential to develop an efficient method for the …

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Nickel Tetrasulphonated Phthalocyanine (Nitspc) Nanostructures Via Polycarbonate Membrane: Enhancement On Optical, Morphological And Electrical Properties / Mirza Mohd Fawwaz Bin Faizan Beg, Mirza Mohd Fawwaz Faizan Beg Jan 2015

Nickel Tetrasulphonated Phthalocyanine (Nitspc) Nanostructures Via Polycarbonate Membrane: Enhancement On Optical, Morphological And Electrical Properties / Mirza Mohd Fawwaz Bin Faizan Beg, Mirza Mohd Fawwaz Faizan Beg

Student Works (2010-2019)

Nickel tetrasulfonated phthalocyanine (NiTsPc) with planar aromatic structures is an ideal building block for organic nanostructures. NiTsPc can self-assemble into stacks through π–π interaction, exhibit high thermal and chemical stabilities, and possess outstanding electrical and optical properties. In this paper, the optical, morphological and electrical properties of NiTsPc nanostructures were investigated. NiTsPc nanostructures were synthesized via polycarbonate membrane of immersion technique. The polycarbonate membrane was immersed in NiTsPc solution for 1 hour and 24 hours. Different annealing temperatures of 50 °C and 100 °C were applied prior to the dissolution of polycarbonate membranes. NiTsPc nanostructures were characterised by UV-Vis spectroscopy, …

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Comparative Biochemical Characterization Of Drosophila Melanogaster Epsilon Class Glutathione S-Transferase, Dmgste6 And Dmgste7 / Vennobaahshini A/P Venu, Vennobaahshini Venu Jan 2015

Comparative Biochemical Characterization Of Drosophila Melanogaster Epsilon Class Glutathione S-Transferase, Dmgste6 And Dmgste7 / Vennobaahshini A/P Venu, Vennobaahshini Venu

Student Works (2010-2019)

The study compares the biochemical behavior of two epsilon class Glutathione S- Transferase (GSTs) genes from Drosophila melanogaster, namely gste6 and gste7. Both GSTs were cloned, expressed and homogenously purified using a combination of anionic exchange chromatography and GSH-affinity matrix. Bioinformatics analysis indicated that both shared 83% and 69% amino acid sequence similarity and identity respectively. Each GSTE6 shared 79% and 77% similarity and GSTE7 has 77% similarity towards GST6A and GST6B of Musca domestica, respectively which are known to participate in resistance towards insecticides. The expressed recombinant proteins were tested for their activity towards 12 model substrates. Based on …

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Socio-Economic Analysis On Waste Pickers In Selected Municipal Solid Waste Disposal Sites In Malaysia / Aida Husna Binti Zahariman, Aida Husna Zahariman Jan 2015

Socio-Economic Analysis On Waste Pickers In Selected Municipal Solid Waste Disposal Sites In Malaysia / Aida Husna Binti Zahariman, Aida Husna Zahariman

Student Works (2010-2019)

Waste production in Malaysia has increased to 30,000 ton per day. It is estimated that 90% of the waste is sent to landfills without any recovery of recyclable materials. This situation provides the waste pickers with a way to make a living by recovering the said materials. The purpose of this study is to understand the socio-economics of the waste pickers in three landfills in Selangor. The three landfills are: a sanitary landfill in Jeram, a non-sanitary landfill in Dengkil, and an open landfill in Bukit Beruntung. Both the Jeram and Dengkil landfills are under the management of Worldwide Holdings, …

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Visualization Of Localized Movement Of Vitamin D Receptor Using Molecular Dynamic Simulation Approach / Wong Wai Keet, Wai Keet Wong Jan 2015

Visualization Of Localized Movement Of Vitamin D Receptor Using Molecular Dynamic Simulation Approach / Wong Wai Keet, Wai Keet Wong

Student Works (2010-2019)

Research on treatments of rickets had led to the discovery of Vitamin D back in the early nineties. Vitamin D is synthesised through exposure of skin to sunlight and then transported to liver and kidney for activation process. Recent research showed that there are quite a number of targeted cells which uptake Vitamin D through the intra-cellular receptor, Vitamin D receptor (VDR). The purpose of this study is to visualise the changes of VDR during the present of Vitamin D. Molecular dynamic simulation was implemented to carry out this study. PDB file (1DB1) of the latest entry in PDB was …

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Dynamics Of Attached And Free-Living Bacterial Population In Tropical Coastal Waters / Lee Siew Wen, Siew Wen Lee Jan 2015

Dynamics Of Attached And Free-Living Bacterial Population In Tropical Coastal Waters / Lee Siew Wen, Siew Wen Lee

Student Works (2010-2019)

We investigated the dynamics of attached and free-living bacterial abundance over a period of 18 months in tropical coastal waters of Malaysia. We measured at both oligotrophic coastal water (Port Dickson) and eutrophic estuary (Klang), and hypothesized that attached bacteria are predominant in eutrophic waters. We also addressed whether attached and free-living bacteria differ phylogenetically. We found that bacterial abundance was higher at Klang than Port Dickson (Student’s t-test: t = 4.87, df = 19, P < 0.001). Attached bacteria also formed a large fraction of the total bacteria at Klang (75 ± 13%) relative to Port Dickson (56 ± 22%), and showed preference for chlorophyll a based particles rather than total suspended solids. The bacterial community structure was clearly different between the two stations but was similar between the attached and free-living bacterial population. Our results showed the importance of attached bacteria in eutrophic water where they could play a major role in carbon and nutrient cycling.

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Proteins Inhibiting Angiotensin Converting Enzyme Derived From Pleurotus Pulmonarius Mycelium (Fr.) Quél / Badjie Xietaqieuallah Binti Ibadallah, Badjie Xietaqieuallah Ibadallah Jan 2015

Proteins Inhibiting Angiotensin Converting Enzyme Derived From Pleurotus Pulmonarius Mycelium (Fr.) Quél / Badjie Xietaqieuallah Binti Ibadallah, Badjie Xietaqieuallah Ibadallah

Student Works (2010-2019)

Pleurotus pulmonarius (grey oyster mushroom) is a well-known edible mushroom that has been acknowledged as a curative agent for many diseases. The antihypertensive potential of Pleurotus pulmonarius mycelium was investigated in vitro via angiotensin converting enzyme (ACE) inhibitory activity. The study was commenced with cultivation of P. pulmonarius mycelium using small scale liquid submerged fermentation for seven days in which brown sugar-spent yeast medium was used as substrate. The mycelial yield was separated from the whole broth to produce mycelial aqueous extract and broth extract, respectively. A preliminary ACE inhibitory assay was performed on the mycelial aqueous extract and broth …

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Feasibility Of Fe3o4 Nanoparticles Decorated Reduced Graphene Oxide Heterostructure As Photocatalyst And Chemical Sensors / Teo Peik See, Peik See Teo Jan 2015

Feasibility Of Fe3o4 Nanoparticles Decorated Reduced Graphene Oxide Heterostructure As Photocatalyst And Chemical Sensors / Teo Peik See, Peik See Teo

Student Works (2010-2019)

In this study, iron oxide/reduced graphene oxide (Fe3O4/rGO) nanocomposite materials were successfully synthesized via a simple, eco-friendly and cost-effective approach at room temperature. The XRD spectra indicated peaks that attributed to the face-centre-cubic phase Fe3O4, while the absence peak of GO in nanocomposite provides evidence for the reduction of GO. The field emission scanning electron microscopic (FESEM) images showed Fe3O4 nanoparticles were uniformly deposited on the rGO sheets with a narrow size distribution for all the nanocomposites. Besides, the synthesized Fe3O4/rGO nanocomposites were found to be superparamagnetic in nature at room temperature. In the photocatalysis application, methylene blue (MB) solution …

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Hirarc Study For Occupational Safety And Health Evaluation Of Clinical Waste Handlers At A Hospital And An Incineration Plant / Kauselya Muniandy, Kauselya Muniandy Jan 2015

Hirarc Study For Occupational Safety And Health Evaluation Of Clinical Waste Handlers At A Hospital And An Incineration Plant / Kauselya Muniandy, Kauselya Muniandy

Student Works (2010-2019)

Clinical waste poses serious threats and hazards to human health. Clinical waste, which is categorized as a scheduled waste in Malaysia, has been increasing over the years. Thus, proper clinical waste management is important as improper clinical waste handling has led to many incidents involving handlers over the years (Arab et al., 2008). However, research on hazard and risk assessment for clinical waste management has been very limited, and there is a serious dearth of information for risk control planning. This project seeks to document the hazards found during clinical waste collection and disposal practices in a healthcare establishment and …

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Penerapan Informal Dan Formal Pendidikan Alam Sekitar Di Suatu Kawasan Tercemar / Baniah Bt Mustam, Baniah Mustam Jan 2015

Penerapan Informal Dan Formal Pendidikan Alam Sekitar Di Suatu Kawasan Tercemar / Baniah Bt Mustam, Baniah Mustam

Student Works (2010-2019)

Masalah alam sekitar kian meruncing walaupun pelbagai usaha telah dilakukan untuk mengatasinya. Pendidikan merupakan suatu kaedah pembentukan sikap dan tingkah laku yang baik terhadap alam sekitar. Sehubungan dengan ini, kajian ini telah 2 menerokai konsep penerapan Pendidikan Alam Sekitar dalam kalangan pelajar, guru dan ibu bapa. Di samping itu, kajian ini juga menyelidik tentang kaedah penerapan Pendidikan Alam Sekitar secara informal dan formal di rumah dan di sekolah. Permasalahan yang wujud berkaitan dengan penerapan dan model mental pelajar yang terbentuk hasil dari penerapannya turut dikaji. Pengumpulan data adalah melalui pendekatan secara kualitatif iaitu pemerhatian, temu bual dan soal selidik terbuka. …

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Neuro – Genetic Model For The Projection Of Crude Oil Price Capable Of Handling Of Uncertainty / Haruna Chiroma, Chiroma Haruna Jan 2015

Neuro – Genetic Model For The Projection Of Crude Oil Price Capable Of Handling Of Uncertainty / Haruna Chiroma, Chiroma Haruna

Student Works (2010-2019)

Some events occur sometimes without any warning, such as war, revolution, financial crises, terrorist attacks, political conflicts, false news, natural disasters, earthquakes, and extreme weather conditions. These types of events which we termed as uncertain events, when related to crude oil have significant effects on the price and will contribute to oil price volatility. Volatility in crude oil market has direct and indirect negative effects on the global economy and inflicts suffering on communities across the globe. The effects of crude oil volatility have no geographical boundary as there is no restriction to a specific country or region of the …

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Study Of Dna For Molecular Analysis And Biochemical Markers From Non-Invasive Samples In Beta-Thalassaemia Major Patients / Mohd Rashdan Abd Rahim, Abd Rahim Mohd Rashdan Jan 2015

Study Of Dna For Molecular Analysis And Biochemical Markers From Non-Invasive Samples In Beta-Thalassaemia Major Patients / Mohd Rashdan Abd Rahim, Abd Rahim Mohd Rashdan

Student Works (2010-2019)

Beta-thalassaemia is a common genetic disorder in Malaysia. It is a haemolytic anaemia which is caused by mutations within the β-globin gene complex, affecting the synthesis of β-globin chains. This will result in excessive free α-globin chains causing α-globin chain toxicity. Erythropoiesis is also impaired leading to chronic anaemia. Beta-thalassaemia major babies may appear healthy at birth. However, symptoms such as jaundice and anaemia will start to develop as they reach six months of life. They require frequent transfusions to maintain haemoglobin levels which lead to iron-overload. Although chelation therapy is recommended, the patients are still under oxidative stress. Patients …

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Synthesis And Characterization Of Multiwall Carbon Nanotubes Using Microwave Heating For Removal Of Heavy Metals / Mubarak Mujawar, Mujawar Mubarak Jan 2015

Synthesis And Characterization Of Multiwall Carbon Nanotubes Using Microwave Heating For Removal Of Heavy Metals / Mubarak Mujawar, Mujawar Mubarak

Student Works (2010-2019)

Carbon nanotubes (CNTs) are among the most eminent materials in the first rank of the nanotechnology revolution. The most eye-catching features of these structures are their electronic, mechanical, optical and chemical characteristics, which open a way for future applications. A new method is introduced for synthesis of CNTs by gas phase, single stage microwave assisted chemical vapor deposition (MA-CVD) using ferrocene as a catalyst and acetylene (C2H2) and hydrogen (H2) as precursor gases. A fast CNTs growth and ambient reaction condition, lowers the cost, and simplifies the procedure leading to a high yield synthesis of high-quality CNTs with minimal impurity …

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Transcriptome Profiling Of Omental Adipose Tissues In Human Obesity By Rna-Seq / Ng Hien Fuh, Hien Fuh Ng Jan 2015

Transcriptome Profiling Of Omental Adipose Tissues In Human Obesity By Rna-Seq / Ng Hien Fuh, Hien Fuh Ng

Student Works (2010-2019)

Recent scientific research has indicated that inflammation in adipose tissues plays a central role in the pathophysiology of obesity and related complications. However, despite extensive studies, the molecular mechanisms that trigger and aggravate the obesity-related inflammation remain unclear. In this study, transcriptome profiling of omental adipose tissues from three obese and four lean patients was performed using the RNA-Seq technology. Differential expression analysis identified 206 dysregulated genes (p-value < 0.05 and fold change ≥ 2) in obesity, that are known to be involved in a multitude of functions including stress response, inflammatory response and leukocyte adhesion. Furthermore, differential splicing analysis uncovered a possible role for TLR4 RNA splicing in obesity, which is further validated with an independent cohort of samples (five obese and six lean patients) using RT-qPCR. These findings suggest that, as a person experiences weight gain leading to obesity, the adipose splicing pattern of TLR4 transcripts changes in favor of activation of TLR4 signaling, which in turn, may contribute to the progression of obesity-related inflammation and complications. This study provides a glimpse at the transcriptome of disease-state adipose tissue in obesity, and demonstrates the potential importance of aberrant RNA splicing and expression in obesity-associated immune dysregulation.

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Utilization Of Functionally Graded Materials In Femoral Prosthesis / Azim Ataollahi Oshkour, Oshkour Azim Ataollahi Jan 2015

Utilization Of Functionally Graded Materials In Femoral Prosthesis / Azim Ataollahi Oshkour, Oshkour Azim Ataollahi

Student Works (2010-2019)

Total hip replacement is a highly effective surgical operation that relieves pain and restores the function of a degenerated hip joint. However, with the increasing incidence of total hip replacements, particularly among young patients, and femoral prosthesis implantation, implant designs should consider long-term survival and better performance. Minimizing the mismatch between the prosthesis and bone stiffness to reduce stress shielding and retain interface stresses within acceptable levels, can increase the longevity of total hip replacement and enhance the performance of the prosthesis. A prosthesis with adjustable stiffness may enable prosthetists to match the prosthesis and bone stiffness. Functionally graded materials …

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Dengue Rapid Diagnostic Via Surface Plasmon Resonance Biosensor / Peyman Jahanshahi, Jahanshahi Peyman Jan 2015

Dengue Rapid Diagnostic Via Surface Plasmon Resonance Biosensor / Peyman Jahanshahi, Jahanshahi Peyman

Student Works (2010-2019)

The aim of this thesis is to introduce an optical technique which can be utilized in detection of dengue virus rapidly. This technique involves the application of analytical and numerical electromagnetic simulations led by physical insight and theoretical knowledge. As a part of this study, the most common permittivity function models are compared and the best model is identified for the proposed biosensor structure. The best model (Brendel-Bormann) is found to have an accuracy of ~94.4% with respect to experimental data. On the other hand, Finite Element Method (FEM) is found to be a valuable tool in the numerical solutions …

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Influences Of Seepage Into Walls, Curvature And Bifurcation On Pressure Drop Calculation In Idealized Arteries : A Computational Fluid Dynamics Approach / Govindaraju Kalimuthu, Kalimuthu Govindaraju Jan 2015

Influences Of Seepage Into Walls, Curvature And Bifurcation On Pressure Drop Calculation In Idealized Arteries : A Computational Fluid Dynamics Approach / Govindaraju Kalimuthu, Kalimuthu Govindaraju

Student Works (2010-2019)

Evaluation of physiological significance of coronary stenosis severity is of great importance than the anatomical significance to identify potentially ischemic stenosis for revascularization whereas non-culprit stenosis has been deferred from stenting. In a clinical settings, the functional severity of the stenosis is evaluated by fractional flow reserve (FFR) which is derived from mean pressure drop ( p ~  ) across the stenosis. The other parameters such as Pressure Drop Coefficient (CDP) and Lesion Flow Coefficient (LFC) which are derived from fluid dynamic principles also useful to evaluate the functional severity of the stenosis. The diagnostic accuracy of measuring severity …

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Performance Of High-Temperature Enhanced Biological Phosphorus Removal Process And Microbial Study Of Its Polyphosphate Accumulating Organisms And Glycogen Accumulating Organisms / Ong Ying Hui, Ying Hui Ong Jan 2015

Performance Of High-Temperature Enhanced Biological Phosphorus Removal Process And Microbial Study Of Its Polyphosphate Accumulating Organisms And Glycogen Accumulating Organisms / Ong Ying Hui, Ying Hui Ong

Student Works (2010-2019)

Enhanced biological phosphorus removal (EBPR) process is commonly applied for the removal of phosphorus (P) from wastewater. Realizing the rapid urbanization and population growth around the world, nutrient pollution problems has gained global concerns. The increasing array of Malaysia’s regulatory requirements on sewage treatment plants (STPs) is part of the abatement strategies on nutrient pollution issue. Reliably meeting low effluent limits can be difficult when EBPR process operated at temperature higher than 25oC. Thus, there is an urgent need to evaluate the applicability and compliance accountability of EBPR process for STPs in tropical climates with relatively high temperatures around 25oC …

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Development Of Thulium-Doped And Co-Doped Fiber Lasers For 1.9 Micron Region Operation / Norazlina Saidin, Saidin Norazlina Jan 2015

Development Of Thulium-Doped And Co-Doped Fiber Lasers For 1.9 Micron Region Operation / Norazlina Saidin, Saidin Norazlina

Student Works (2010-2019)

1.9 μm fiber lasers offer numerous applications in the area of spectroscopy, military and medical field. Thulium doped fiber has been used in order to realize laser applications in this region. Various methods have been implemented to achieve high output power as well as low threshold pump power for the laser’s applications. Other than being used for continuous wave operation, pulse lasers are also important in various fields of applications including high-precision material processing, biomedicine and ranging. This thesis thoroughly describes the development of 1.9 μm fiber lasers based on thulium doped and co-doped fibers as the gain medium. Two …

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Effect Of Ultrasonication On Colloidal Thermophysical And Rheological Properties Of Alumina-Water Nanofluid / Mohammed Mahbubul Islam, Mahbubul Islam Mohammed Jan 2015

Effect Of Ultrasonication On Colloidal Thermophysical And Rheological Properties Of Alumina-Water Nanofluid / Mohammed Mahbubul Islam, Mahbubul Islam Mohammed

Student Works (2010-2019)

Nanofluids are promising fluids for heat transfer applications. Low stability and high viscosity are two important drawbacks for practical applications of nanofluids. The aggregation and sedimentation of nanoparticles are related to the colloidal dispersion characteristics, which directly affect the stability and thermophysical properties. An ultrasonic homogenizer can break the aggregation of particles and disperse them into a fluid to improve the stability of the suspension. Therefore, sound energy is needed to improve thermal energy. However, the research question is whether the improvement achieved in thermal application is feasible for the amount of used ultrasound energy. The aim of this research …

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Kinetic Mechanism And Equilibrium Thermodynamic Of Lipase Catalyzed Synthesis Of Rutin Flavonoid Ester / Nurul Nadiah Abd Razak, Abd Razak Nurul Nadiah Jan 2015

Kinetic Mechanism And Equilibrium Thermodynamic Of Lipase Catalyzed Synthesis Of Rutin Flavonoid Ester / Nurul Nadiah Abd Razak, Abd Razak Nurul Nadiah

Student Works (2010-2019)

Flavonoids are natural compounds in plant with wide spectrum of healthbeneficial activities. They exhibit a variety of physico-chemical properties and biological activities but they are normally characterized by low solubility and stability. In order to improve upon these limitations, the enzymatic acylation of these molecules with fatty acids is seen as a selective, specific and mild route. In this study, the synthesis of flavonoid esters catalyzed by lipase was investigated. Three different flavonoid structures from different classes were selected to be studied viz. rutin (flavonols), naringin (flavanones) and catechin (flavanols). The effects of these flavonoid structures on the esterification were …

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Synthesis And Characterization Of Polyaniline For Hydrazine Detection / Kavirajaa Pandian Sambasevam, Sambasevam Kavirajaa Pandian Jan 2015

Synthesis And Characterization Of Polyaniline For Hydrazine Detection / Kavirajaa Pandian Sambasevam, Sambasevam Kavirajaa Pandian

Student Works (2010-2019)

Among the conducting polymers, polyaniline (PAni) is studied most extensively due to the ease of synthesis, high conductivity and low production cost. Hydrazine from fuels, pesticide and corrosion inhibitor industries are a toxic compound which can cause neurotoxicity and carcinogenicity. In this study, a series of PAni were synthesized and applied as a chemical sensor for hydrazine detection. The sensor responses of PAni were monitored by ultraviolet-visible (UV-Vis) analysis in hydrazine detection. Besides, the sensor response was supported by conductivity study and Fourier transform infrared (FTIR) analysis to identify the chemical interaction between the PAni and the hydrazine. Doped-PAni were …

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Chemical Constituents From The Rhizomes Of Curcuma Zedoaria And Curcuma Purpurascens And Assessment Of Their Biological Activities / Omer Abdalla Ahmed Hamdi, Ahmed Hamdi Omer Abdalla Jan 2015

Chemical Constituents From The Rhizomes Of Curcuma Zedoaria And Curcuma Purpurascens And Assessment Of Their Biological Activities / Omer Abdalla Ahmed Hamdi, Ahmed Hamdi Omer Abdalla

Student Works (2010-2019)

Curcuma zedoaria (Christm.) Rosc. (local name: Temu putih) and Curcuma purpurascens are two medicinally important plants of the genus Curucma and grow abundantly in Asian countries including Malaysia and Indonesia. These two plants are extensively used in the traditional medicinal practice of Malaysia and many other countries of the world for the treatment of various ailments. Phytochemical investigation of the rhizomes of C. zedoaria and C. purpurascens resulted in the isolation of 27 compounds. C. zedoaria afforded eighteen sesquiterpenes, including eight germacrane type (dehydrocurdione 19, curdione 20, furanodiene 21, furanodienone 22, germacrone 23, germacrone 4,5-epoxide 24, germacrone 1,10-epoxide 25, and …

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Chemical Constituents Of Phoebe Grandis (Nees) Merr, Phoebe Tavoyana (Meissn.) Hk.F., And Actinodaphne Sesquipedalis Hook. F. Var. Glabra And Their Biological Activities / Hanita Omar, Omar Hanita Jan 2015

Chemical Constituents Of Phoebe Grandis (Nees) Merr, Phoebe Tavoyana (Meissn.) Hk.F., And Actinodaphne Sesquipedalis Hook. F. Var. Glabra And Their Biological Activities / Hanita Omar, Omar Hanita

Student Works (2010-2019)

Chemical Constituents of Phoebe grandis (Nees) Merr, Phoebe tavoyana (Meissn.) Hk.F., and Actinodaphne sesquipedalis Hook. F. var. glabra And Their Biological Activities Twenty extracts of Phoebe grandis and Phoebe tavoyana; and Actinodaphne sesquipedalis were underwent preliminary screening for their cytotoxicity, antioxidant, antibacterial and antiplasmodial activities. The potential extracts were chosen for detailed phytochemical investigation involving isolation of compounds by chromatographic methods, structural elucidation by means of spectroscopic methods such as UV, IR, MS, 1D and 2D NMR (COSY, HMQC, HMBC, NOESY) and also by comparison with the literature. Further bioassay screenings for some of the identified compounds were also carried …

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Feasibility Study On Implementation Of Marine Renewable Energy In Malaysia By Considering The Project Costs And Urban Public Acceptance / Lim Xin Le, Xin Le Lim Jan 2015

Feasibility Study On Implementation Of Marine Renewable Energy In Malaysia By Considering The Project Costs And Urban Public Acceptance / Lim Xin Le, Xin Le Lim

Student Works (2010-2019)

Energy demand due to increasing global population and the need for low carbon energy have led to the rising importance of renewable energy. Apart from the three most used renewable energy sources in Malaysia – solar energy, hydroelectric and biomass –marine renewable energy may be another potential player in the renewable energy market. Marine renewable energy, which comprises of tidal energy, wave energy, ocean thermal energy conversion (OTEC) and salinity gradient, can be harnessed in Malaysia as the country is surrounded by abundant water resources. The development of marine renewable energy, however, is currently still in its infancy and may …

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