Pusat Pengajian Sains Fizik - Tesis

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Slow Pyrolysis Of Palm Wastes And Properties Of Biochar Blended Coal Briquettes
(2014-01)
Inuwa, Ibrahim Abdullahi
The disposal of large amount of agricultural residues in developing countries causes a detrimental effect to the environment. Thus, this study is aimed at converting oil palm wastes from oil palm mill, into briquettes to significantly reduce the consequences following the existing disposal system. In this study, pyrolysis experiments were conducted from 300°C to 700 °C with heating rate between 5°C/min to 30°C/min by a lab-scale pyrolysis system. The results obtained showed, the quantity and quality of products mostly depend on the pyrolysis parameters (temperature and heating rate). The calorific value and carbon content of PKS biochar were 28.27 MJ/kg and 72.42%, which is significantly greater than that of coal sample of 26.21 MJ/kg and 64.66%. While moisture and ash content in biochar is 1.02 mfwt% and 4.88 mfwt which is lower than that of coal with 7.40 mfwt% and 6.62 mfwt% respectively. The composite PKS biochar and pure coal (bituminous) are mixed with percentage compositions of 100:0,80:20, 70:30, 60:40, 50:50, 60:40, 70:30 and O: 100 respectively. A different proportion of2, 2.5, 3, 3.5 and 4% cassava starch for the total mass of the mixture were used as the binder. The different compressed pressure of 80, 90,100, 110 and 120 kg/cm2 at 2 dwell times was used. Among the briquettes samples tested p 100 contained lowest moisture of 2.56 mfwt% and ash of 5.36 mfwt% with highest fixed carbon of 54.49 wt %. The increase in pure coal into the blend has led to a reduction in the energy value of the briquette from 29.83 to 25.55 MJkg-l. Cassava used as binder portrayed an insignificant effect in the calorific values of the briquettes. In the water boiling test analysis showed, pure biochar briquette PIOO generates the highest temperature up to 920.67°C compared to biochar-coal mixture briquettes and pure coal sample.
Development Of New Self-potential Acquisition Technique For Ground Subsurface Investigation
(2024-08)
Jinmin, Mark
Self-potential (SP) method is a passive geoelectrical method. It measured the natural potential differences which exist between any two points on the ground. The points are measured using an electrode known as the roving electrode and the base electrode. In the SP method, these electrodes are often called ‘porous pots’ which are designed not to create any chemical potential once they are contacted on the ground. A reference electrode is used as a base electrode, and the second electrode is used to measure the potential on the ground. The primary research is to introduce the practical techniques in SP data acquisition which is Self-Potential Enhancement Technique (SPET). SPET is a combination of techniques which are the electrode calibration technique (EC), the optimum electrode time technique (OET), and the closed loop. Using a pair of electrodes consumes more time and energy during data acquisition. Hence, the EC is to calibrate and correct the electrode error during data measurement, which is able to use multiple electrodes. An inconsistent time period for mitigating an electrode on the ground can lead to inaccurate self-potential data readings. Thus, the OET purpose is to identify the time frame for an electrode to be in equilibrium on the ground. The SP has an electrode configuration for acquiring the electrical potential data such as gradient and fixed base. The gradient technique has some disadvantages in the data quality, such as cumulative error, electrode polarization, drift effect, time-varying potential, soil contact effect, and reading errors.
SNESS - An Expert System Shell
(1994-05)
Singh, Pratul
Looking at the prevailing trend, an attempt has been made in this thesis to develop a shell on PC, using C++ language. C++ language is an extension of C language and it retains the efficiency of C and is compatible with existing C programs. In the present work we have emphasized on the core of an expert system shell which consists of a facility to input knowledge and create a knowledge base and an inference engine that operates on the knowledge base to develop the desired system.
Environmental Impact Assessment Of Abrasive Materials In Industrial Blasting Process
(2024-09)
Amin, Iskandar Zulkarnain Mohd
The environmental impact study of abrasive materials in the blasting industry is a pivotal research endeavour. Abrasive blasting, widely used in surface preparation and painting industries, involves projecting high-pressure abrasive material onto surfaces. This research aims to characterize various abrasive materials and assess their environmental impact. Various proposed abrasive materials, including diamond, garnet, jadecut, ceramic, and two types of glass (Duragrit glass and Glass blast), undergo a meticulous examination of their compound composition and crystallinity, utilizing X-ray Fluorescence (XRF) and X-ray diffraction (XRD) analyses. Both Duragrit glass and Glass blast emerge as promising candidates, displaying an amorphous structure and meeting the Department of Occupational Safety and Health (DOSH) requirements for open blasting. Mechanical properties of these materials are thoroughly characterized, including particle size distribution (ISO11127-2), apparent density (ISO11127-3), hardness (ISO11127-4), moisture content (ISO11127-5), and water-soluble chlorides (ISO11127-7). For instance, apparent density measures 2.17 × 103 kg/m3 for Duragrit glass and 2.5 × 103 kg/m3 for Glass blast, with moisture content at 0.01%. Water-soluble chlorides are Nil for Duragrit glass and 0.0001% for Glass blast. These findings are foundational for effective abrasive blast-cleaning, ensuring safety compliance, and preserving desired surface features. The efficacy of Duragrit glass and Glass blast in surface preparation adheres to industry standards, meeting Petronas Technical Specifications (PTS) and Shell Technical Specifications (STS) requirements.
Multi-layer Radiation Shielding Design For Compact Proton Therapy System Using Monte Carlo Simulation
(2024-09)
Aliyah, Fitrotun
Proton therapy has emerged as a highly effective treatment for various cancers due to its precision in targeting tumor cells while minimizing radiation exposure to surrounding healthy tissues. However, the design of compact proton therapy facilities poses significant challenges, particularly in terms of shielding requirements, cost, and environmental impact. This study aims to develop a novel shielding design for proton therapy systems that complies with regulatory dose limits while reducing the overall cost and footprint by utilizing alternative materials through a multilayer structure model. The research begins with the characterization of natural aggregate and steel slag as potential alternative materials for concrete admixture, then continues with experimental evaluations of radiation attenuation properties using PuBe, LINAC, and CT-Scan as radiation sources. To further develop and optimize the shielding design, the study employed Monte Carlo simulations using the Particle and Heavy Ion Transport code System (PHITS). These simulations facilitated the creation of innovative shielding configurations, incorporating both single-layer and multilayer structures composed of Portland concrete (PC), steel slag concrete (SSC) , iron (Fe), borated polyethylene (BPE), and recycled high-density polyethylene (HDPE). The experiment results demonstrate that steel slag concrete offers superior radiation shielding performance compared to conventional concrete. The PHITS simulation results demonstrate that the material combination model of PC-SSC on the treatment room wall and PC-SSC-Fe-HDPE on the Maze 1 wall is the optimal configuration with ambient dose equivalent rate value ranging from 13 to 773 mSv/year.

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