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Phytoremediation By Aromatic Plants To Remove Heavy Metals From Contaminated Soil : Case Study Of Taiping Landfill
(2014-12)
Mashhoor Rood, Maryam
Heavy metal pollution is a widespread occurrence that causes serious environmental problems. This issue has to be addressed to ensure a safe and clean environment. The use of plant species to remove contaminants from soils is generally described as phytoremediation. Phytoremediation is an environment-friendly and emerging technology that purges contaminated soil and water to a large extent. According to current research, instead of growing edible crops, growing certain aromatic species is feasible. The final product is free from heavy metals so that such aromatic crops are considered to be an excellent choice for phytoremediation. This study evaluates the potential application of thymus vulgaris, sweet basil. Origanum majorana, and portulaca oleracea in the phytoremediation of as, co. Cr, cu, li, mn, ni, pb. V. And zn. Seeds were planted in six different growth media pots, including sn1, sn4, sn8, nn1, nn2, and nn4, their levels in a completely randomized block design with three replications.
Characterization And Utilization Of Extracted Starch And Particles From Oil Palm Trunk For Particleboard Manufacturing
(2014-12)
Mohd Salleh, Kushairi
This study investigated the potential of the oil palm particles and oil palm starch produced and extracted from the oil palm trunk. Commercial rubberwood particles and wheat starch were used as a comparison. The starches were modified with polyvinyl alcohol to change its properties for better performance. Basic properties of raw materials were determined for their final properties of the boards. The raw materials were also characterized using scanning electron microscopy, xray diffractometry analysis, thermogravimetric analysis, and differential scanning calorimetry analysis. Comparisons were made between boards and panels bonded with urea formaldehyde were used as a control board. The physical and mechanical testing carried out based on japanese industrial standard a5908, which include density, moisture content, dimensional stability testing, and mechanical strength. All mechanical properties met the requirements, but none of the physical properties met the requirements except for moisture content. The panels made using the oil palm particles and bonded with the oil palm starch showed better mechanical properties, but poor dimensional stability compared to those panels made with the rubberwood particles, and panels bonded with the wheat starch.
Preparation And Properties Of Polypropylene/Waste Tyre Dust/Short Glass Fibre (Pp/Wtd/Sgf) Composites
(2017-05)
Zainal, Zuriati
Polypropylene/ waste tyre dust/ short glass fibre (pp/wtd/sgf) composites were meltmixed in an internal mixer at 180 °c and 50 rpm rotor speed. Four series of composites with various compositions were prepared using wtd of 250-500 pm and at different 5, 10, 15 and 20 php sgf loading. Characterization was done to determine the properties of the composites and thus to study the effects of sgf loading, the incorporation of silane coupling agent, y-aminopropyltrimethoxysilane (y-aps) and dynamic vulcanization (dv), the hybridization of sgf with carbon black (cb) and silica on processing characteristics, mechanical properties, morphology, swelling resistance and thermal properties of the composites. The incorporation of sgf at various loadings exhibited increased equilibrium processing torque, young’s modulus, tensile strength and thermal stability while elongation at break (eb) and swelling resistance decreased as the sgf loading increased in pp/wtd/sgf composites. Poor interfacial adhesion between sgf and pp/wtd matrix was depicted in the sem analysis. In the meantime, the addition of y-aps, and dv revealed the increased of equilibrium torque, tensile properties except eb and swelling resistance of pp/wtd/sgf composites.
Prediction Of Basic Wind Speed For Oman
(2017-07)
Salim Almaawali, Said Saif
Sultanate of oman is a unique country with its distinct demographic and environmental characteristics typical to this country alone. It is also one of the fastest developing economies, giving rise to a spectacular construction spree seen over the last few years. Oman has no code of practices for wind loading for buildings yet. Hence, many designers adopted foreign codes of practice such as the british standards (bs8110, bs6399) in order to determine the value of basic wind speed for their building design. Such a practice is not appropriate on account of the prevailing differences in climatic and geographic conditions. Therefore, the aim of this study is to develop the value of basic wind speed map using collected daily wind speed from 13 meteorological stations all around oman. The characteristics of wind speed data have been determined using statistical measures such as mean, standard deviation, skewness, and kurtoses using spss software. Three statistical methods namely gumbel, gringorten and cunnane methods were used for two different distributions (gumbel and generalized pareto distributions) using three different data types (all data, peaks over threshold method (pot), and method of independent storms (mis).
Cloud Resource Management Framework Using Monarch Butterfly Harmony Search And Case Based Reasoning
(2017-08)
Ahmed Mohamed Ghetas, Mohamed Rezk
Cloud services have evolved rapidly and some have adopted a multi-tier architecture for flexibility and reusability. Various rule- and model-based approaches have designed to manage quality of service for these services. A few of existing resource management approaches aim to increase the cloud provider (cp) service provisioning profits. However, they are based on local search optimization algorithms, which may not obtain the best resource provisioning decision in a large-scale cloud environment. This research proposes a new resource optimization and provisioning (rop) framework to detect, solve the bottlenecks, and satisfy the service-level qos requirements of several multi-tier cloud services and to increase the cp service provisioning profits. The rop framework consists of two main components: global resource optimizer (gro) and resource identifier (ri). This research enhances the butterfly optimization algorithm and plugs the resulting algorithm into the rop as a gro. In addition, a new ri is developed using case-based reasoning and is then plugged into the rop framework. To demonstrate the effectiveness of the proposed rop against rule- and model-based approaches, a prototype running on a cloud platform is developed, and a workload generator and multi-tier service model are adopted.

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Kesan Pendekatan Pembelajaran Berasaskan Inkuiri Terhadap Pencapaian Dan Pengetahuan Geografi, Motivasi Dan Perlakuan Inkuiri Pelajar Berbeza Pencapaian: Satu Kajian Eksperimen
(Universiti Sains Malaysia, 2013-07)
Nik Mohamed, Nik Mohd Zaki
Kajian ini bertujuan mengenal pasti kesan pendekatan Pembelajaran Berasaskan Inkuiri terhadap prestasi pencapaian geografi pelajar, pengetahuan geografi, perlakuan inkuiri dan motivasi kumpulan pelajar berbeza pencapaian. Kajian ini menggunakan kaedah kuasi eksperimen kumpulan kawalan tidak setara dengan reka bentuk faktorial 3 x 2. Lima orang guru dan 150 orang pelajar daripada tiga buah sekolah di daerah Bera, Pahang terlibat dalam kajian ini. Kumpulan eksperimen telah diberikan olahan pengajaran menggunakan dua model inkuiri iaitu Kitar Pembelajaran 5E dan Inkuiri Geografi 5W. Kumpulan dengan olahan pembelajaran selain inkuiri berfungsi sebagai kumpulan kawalan. Data untuk mengukur pencapaian dan pengetahuan geografi pelajar dalam satu topik pengajaran yang identikal diperoleh menggunakan instrumen ujian. Data berkaitan tingkah laku inkuiri pelajar semasa proses pengajaran dan pembelajaran diperoleh menggunakan Inquiry Observation Protocol. Selain itu, satu set borang soal selidik digunakan untuk memperoleh data motivasi pelajar yang telah menerima olahan Pembelajaran Berasaskan Inkuiri. Dari aspek prestasi pencapaian geografi, analisis ANCOVA dua hala menunjukkan perbezaan yang signifikan di antara kumpulan olahan dan perbezaan pencapaian pelajar. Walau bagaimanapun, terdapat kesan interaksi yang signifikan antara faktor utama kaedah pengajaran dan perbezaan pencapaian pelajar ke atas prestasi pencapaian geografi.
CIT547 – Informatics Project Management (Pengurusan Projek Informatik)
(2023-02)
Pusat Pengajian Sains Komputer
First Semester Examination 2022/2023 Academic Session
Modelling and simulation on mineral processing system
(2025-08-07)
Nur Aida Nazira Malim binti Abdul Kadir
The optimisation of aggregate production in granite quarries requires precise control over comminution processes, particularly when vertical shaft impact (VSI) crushers are employed. This study applies JKSimMet v6.3 software to simulate and calibrate the crushing circuit of a granite aggregate plant, focusing solely on model fitting to replicate actual plant performance. Data from two quarry sites which are one in Juru and another in Pasir Gudang were utilised to construct a representative flowsheet. The VSI crusher was the primary focus of the simulation, with emphasis placed on adjusting breakage parameters such as k1, k2, k3, and t10, which respectively influence particle selection, size dependency, breakage rate, and product fineness. These parameters were iteratively tuned to match the plant’s particle size distribution (PSD) output, using JKSimMet’s graphical output as a validation reference. While mass balancing was not a core component of this project, model fitting alone was sufficient to achieve a high correlation between simulated and actual PSD curves. The results underscore the potential of simulation as a non-intrusive tool for improving circuit understanding and evaluating design modifications before physical changes are implemented. This research demonstrates that by focusing on parameter refinement within the model fitting process, engineers can gain practical insight into VSI crusher performance and its impact on overall plant efficiency and product quality.
Extraction Of Secondary Metabolite In Tetraselmis Suecica Using Different Solvent Polarity
(2020-06)
Mohd Din, Muhammad Alif Faiz
Recently, there has been much interest in secondary metabolites extracted from natural sources including microalgae for the food industry as well as pharmaceutical, cosmetic, and nutraceutical sectors. These interests have been increasing among researchers nowadays. Therefore, the present investigation was undertaken to analyse the secondary metabolite from Tetraselmis suecica which is a marine microalga. Briefly, T. suecica was cultured in normal conditions in the F/2 medium. During 15 days of monitoring of the cell growth, the absorbance reading at 680 nm was recorded. Then, its biomass was further extract by using solvent extraction method. Further, the extract was obtained using different solvent polarity which are hexane, ethyl acetate, and methanol. The yield extract was calculated and was revealed that extraction using hexane as solvent was the best among those three solvents. The resulted extract using different solvent polarities was further analyse using GC-FID. There were several peaks present in the chromatogram of extract using the solvents tested, however, there is no peak in the chromatogram of extract using methanol. This can be concluded that there was a compound which is C10 (Methyl Decanoate) in the chromatogram of extract using hexane and several compounds in the chromatogram of extract using ethyl acetate such as C10 (Methyl Decanoate), C12 (Methyl Dodecanoate) and C14 (Methyl-Cis-9- Tetradecanoate)
ZnO And MoSexOy Modified TiO2 Nanotubes For Photoelectrochemical And Sensing Applications
(Universiti Sains Malaysia, 2018-09)
Ng, Siow Woon
One-dimensional (1D) anodic self-organized TiO2 nanotube layers have attracted considerable scientific and technological interest over a decade. The major drawbacks are their rather wide band gap energies (3.0–3.2 eV) with high photoactivity only in the ultraviolet (UV) spectral region (l 390 nm, 5% of the solar spectrum), relatively low conductivity and high carrier recombination rate. Furthermore, as a high aspect ratio (HAR) nanostructure, the deposition of a uniform secondary coating within the TiO2 nanotube layers remains a challenge. To overcome these critical issues, present work is intended (i) to synthesize anodic 1D TiO2 nanotube layers as an independent semiconductor and for the incorporation of secondary materials; (ii) to produce homogeneous and conformal ZnO and MoSexOy coatings by atomic layer deposition (ALD) within TiO2 nanotube layers; (iii) to form heterostructure in order to enhance charge transport efficiency, increase light absorption and extend the functional range to the visible spectral region; and (iv) to evaluate UV photodetection responses, ethanol sensing responses at low temperatures, photocurrent generation and photocatalytic degradation of methylene blue (MB). The synthesis of the TiO2 nanotube layers was carried out by a conventional electrochemical anodization of Ti sheet in fluorinated organic electrolytes. A low bias, visible-blind, UV photodetector was constructed in a sandwich structure comprising of ITO/electrolyte/TiO2 nanotubes/Ti for the first time to investigate the photodetection in UV-A, B and C spectral regions. The highest sensitivity was credited to 5 mm TiO2 nanotube layer, with sensitivity 850, responsivity 740 mA/W and short rise and decay time less than 1.5 s. Synergistic effects arising from the deposited materials and TiO2 core layer strongly influenced the photoelectrochemical (PEC) properties and substantially enhanced the photocurrent conversion efficiencies. The ZnO (19 nm) coated nanotube layers presented 80–95% incident photon-to-electron conversion efficiencies (IPCE) between 305–375 nm with the aid of 2 V bias. This value is among the highest values reported for ZnO/TiO2 combination. The MoSexOy (2 nm) coated layers demonstrated up to 40-fold higher photocurrent than the blank nanotube layers at 470 nm. As an environmental application, the MoSexOy coatings have shown to be an effective photocatalyst for MB degradation with significantly accelerated photocatalytic degradation rates at 2.259 10􀀀2 min􀀀1. It is also for the first time, MoSexOy is synthesized by ALD and deposited within HAR nanostructure. Finally, the ZnO coatings yielded an improved ethanol sensing response up to 11-fold compared to the blank nanotube layers in operating temperatures of 100– 200 C with high stability, durability, and reproducibility. Overall, the current work demonstrated that anodic self-organized TiO2 nanotube layer is functional as a sensing layer for UV and ethanol detection; and a photocatalyst in PEC and photodegradation activities.