Muhammad Azwadi Sulaiman

Effects of Soil Physical Properties to the Corrosion of Underground Pipelines

Corrosion of metals in soil be able to change from comparatively fast material loss to insignificant effects, depending on soil environment. Corrosion is a process of deterioration of metal surfaces degraded into another compound. Soil is one of the medium known to have constituted to corrosion of metals. The soil creates an environment for the corrosion to react. The buried pipelines are exposed to the soil that may experience corrosion attack. The study of the soil as corrosion environment is important to mitigate the problem due to the environment and economy. There are factors that contribute to the corrosion process. This study concentrates on corrosion properties that expose to soil environment particularly underground pipelines. The mild steel coupons taken from actual pipelines, stimulating and analyzing the physic-chemical characteristics of the soil environment. The soil is sandy clay in natural. A total summed index of 2 numerical scale, thus, indicates that the soil tested was mildly to non-corrosive. The corrosion rate increase with increasing of moisture content and pH value. The observations on the coupon surface also did in order to study the morphology.

Morphology of CuO-Doped Activated Carbon from Kenaf Core Fiber

Mechanochemical process was conducted to synthesis a series of metal oxide doped biomass carbon source followed by carbothermal reduction which obtained via the reaction between activated carbon (AC) and CuO precursor. Microstructure of single AC and CuO-doped activated carbon was conducted using Field Emission Scanning Electron Microscopy (FESEM). Thermal behavior was studied using thermogravimetric analyser and Differential Scanning Calorimetry (TGA and DSC) and crystallinity phase was analysed using X-ray diffraction (XRD). The results indicated that mechanochemical process and carbothermal reduction to synthesis CuO-doped AC have a significant effect in term of surface morphology, thermal decomposition and crystallinity. A significant difference of the surface morphology between AC and CuO-AC samples were observed. TGA/DSC analysis revealed that doping of CuO to AC has affected the exothermic and endothermic reaction of the samples. Doping of CuO to AC also brought a significant increase in the degree of crystallinity due to the carbothermal reduction of CuO into Cu. Production of CuO-doped AC was successfully characterized and revealed the potential enhancement for waste treatment.

Effect of Sintering Heating Rate on CaCu 3 Ti 4 O 12 Formation

CaCu3Ti4O12 (CCTO) is an electroceramic material with complex cubic perovskite-like oxide. It possessed a giant dielectric constant of about 105 over a wide temperature range (100-600 K). In this work, CCTO was synthesized through solid state method. The effect of different heating rate during sintering process was studied. The raw materials - CaCO3, CuO and TiO2 were wet ball milled for 24 hours and calcined at 900 °C for 10 hours. Then the calcined powder was pressed into pellet shape at 300 MPa. Sintering was done at 1040 °C for 12 hours with different heating rates: 3, 5 and 10 °C/min. The phase formation and surface morphology was investigated by X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscope (FESEM), respectively. The density was measured by Archimedes Principle. XRD pattern proves the CCTO single phase formation for the calcined powder and sintered pellet. The SEM images show the different grain size for different heating rate. The density of the pellet was found to be reduced when faster sintering heating rate was used.

Microstructural, Mechanical and Dielectric Properties of CCTO/Epoxy Composite

An attempt has been made to investigate the relationship between different composition of CaCu3Ti4O12 (CCTO)/epoxy to the microstructural, dielectric and mechanical properties respectively. CCTO powder had been produced through solid state reaction method using CaCO3, CuO and TiO2 as the raw materials. They were mixed at stoichiometric ratio and calcined at 1040°C for 10 hours. CCTO powder mixed with epoxy and hardener at different weight percentage (10, 20, 30, 40 and 50 wt%). Microstructure of fracture surface of the composite had been studied using Field Emission Scanning Electron Microscopy (FESEM) and mechanical characterization had been conducted using Universal Testing Machine (UTM). LCR meter Agilent 4284A was used to measure the dielectric properties at 20 Hz to 1 MHz. Increasing CCTO concentration to the composite caused a significant change of dielectric constant which arised from 17.1 to 23.5 at 1 kHz. This arising due to higher concentration of CCTO filler transfer more intrinsic values to the composite. Tensile test shows an increment to stress value from 4 to 17 MPa as the respond on increasing of ceramic filler concentration. High stiffness of CCTO have increased the strength of the composite. The dispersion of higher weight percentage of the CCTO into the epoxy is more compacted than the dispersion of lower weight percentage of CCTO. It is best to mix the higher amount of filler into the polymer matrix to increase the dielectric and strength of the composite material.

Microstructure of CuO Assisted Activated Carbon Adsorbent from Rubber Wood Sawdust Produced by Mechanochemical Processing

A series of single carbon source and metal oxide assisted carbon source were prepared by mechanochemical process followed by carbothermal reduction which obtained via the reaction between activated carbon (AC) from rubber wood sawdust (Havea brasiliensis) and CuO precussor. Microstructure of the single AC and CuO assisted AC (CuO-AC) has been studied using Field Emission Scanning Electron Microscopy (FESEM). The products were further characterized using X-ray diffraction (XRD) and thermal analysis (TG and DTA). A significant difference of the microstructure between AC and CuO-AC samples were observed in FESEM micrograph. The micrograph of single AC in indicates porous structure with numerous pores present due to dehydration of volatile matters. Milling process and reduction of CuO by AC has contributed to the increasing formation of porous structure with nanopore size ranging from 100-200 nm. TG and DTA results revealed that single AC and CuO-AC have a significant difference in thermal decomposition and stability. Doping of CuO to AC has affected the exothermic and endothermic reaction of the samples. These were further being clarified by X-ray diffraction where phase analysis is studied. It was found that the addition of CuO to AC brought a significant increase in the degree of crystallinity which is accompanied by mechanochemical process followed by carbothermal reduction to produce Cu. Incomplete reduction also cause the formation of Cu2O. Production of CuO-AC were successfully characterized and revealed the potential enhancement for waste treatment.

Flexural and Morphology Properties of Kenaf Fibre Reinforcement Unsaturated Polymer Composite

This study focus on the preparation of kenaf fibre reinforced unsaturated polyester composite through the compressing molding technique. The composite characterizations in flexural and morphological properties. Flexural test revealed that the incorporation of multiple layers of kenaf mat into unsaturated polymer composite (UPE) resulted in the increase of flexural strength. Nevertheless, the UPE alone still showed superior flexural strength since the presence of natural filler/fibre in polymer tends to reduce strength properties. The results proved that the UPE revealed the formation of microcracks. Thus, it has been noticed that the fiber fracture, fiber debondings and holes are some of the defects, which are observed due to the application of the load on the specimen.

Mechanical and Water Absorption Properties of Hybrid Kenaf/Glass Fibre Mat Reinforced Unsaturated Polyester Composites

Hybrid kenaf/glass fibre mat reinforced unsaturated polyester (UPE) composites have been prepared by using simple hand lay up moulding technique. The composites with various formulations were characterized by flexural test while water absorption behaviour were investigated with immersion in distilled water at room temperature. The result shows that the hybrid composites with kenaf fibre mat at the innermost layers (glass fibre mat at the outer layers) has given the highest flexural strength and modulus. On the other hand, water absorption study shows that, the hybrid composites with glass fibre mat at the innermost layers (kenaf fibre mat at the outer layers) showed the highest water uptake and thickness swelling. Further investigations on morphological properties were also done to correlate the mechanical properties of the hybrid kenaf/glass fibre mat reinforced UPE composites.

The Dielectric Properties of CaCu3Ti4O12 at Various Calcination Temperatures

High dielectric constant of CaCu3Ti4O12 (CCTO) has drawn a great deal of intention these past years as potential material for capacitor and even micro-electronic applications. In this research, an attempt has been made to investigate the relationship between the calcination temperature and the dielectric properties of CCTO. The calcination of CCTO at lower temperature (below 1000○C) provides incomplete reaction process, where the secondary phase is detected on the sample. Calcination at 1040○C provides a single phase as just same with the control sample (sample which had gone through both phase calcine and sinter). It is also found that calcination at 1040○C provides the dielectric properties that almost the same with the calcine-sinter sample.

Characterizations of Pergau River Clay as Comparison to Mambong and Sayong

Clay as pottery’s raw material is a major factor that is affecting the quality and reliability of any pottery product. The clay source areas need to be well determined their geochemical properties in order to control the end properties of clay product. Pergau river is located in the northwest of Kelantan, a state in Malaysia. In this study, elemental and phase analysis of Pergau river clay was carried out. The baked clay products were characterized their density and toughness. X-ray fluorescence showed the clay is rich with Fe and X-ray diffraction showed low concentration of feldspar compared to other known clay source areas, which are Sayong and Mambong. Fewer feldspar content decrease toughness of the pottery product. However, some location showed the comparable result with the Sayong and Mambong. The clay is high in density, low in shrinkage percentage and excellent in mechanical strength compare to other clays collected from Pergau River.

A Survey on Occupational Safety and Health Awareness Among School Teachers in Kelantan, Malaysia

Nowadays, more accident cases reported in school cause not only injuries, but also deaths. This indicates that the importance of safety and health measures in school should be exposed not only to students but most importantly to teachers who will be guiding and providing safety and health culture in school. This paper is based on the study that was motivated by the increasing reports of accidents in school. The objective of the study was to measure the understanding regarding safety and health among school teachers in Kelantan by distributing questionnaires consist of ten District Education Offices (PPD) in Kelantan, Malaysia. The results show that most of the respondents understand about safety and health matters with the importance of implementing safety and health in school. In conclusion, further study on workplace assessment need to be conducted at school to identify the implementation of safety and health among school community.