Tin slag was collected from a slag dump in the Penang Island and was analysed for its elemental composition using microfocus XRF with a 300ȝm x-ray spot diameter. The tin slag sample was analysed direct without any sample treatment and analysis was conduct on four different spots. The result gives different elemental composition on these different spots. Among the elements analysed are Al2O3, SiO2, SnO2, CaO, TiO2, Nd2O3, MnO, Fe2O3, TaO, W2O3, As2O3, ThO2, U3O8, ZrO2 and Nb2O5. Elemental mapping was also done to show the distribution of these elements in the sample.
Even though EDXRF analysis has major advantages in the analysis of stainless steel samples such as simultaneous determination of the minor elements, analysis can be done without sample preparation and non-destructive analysis, the matrix issue arised from the inter element interaction can make the the final quantitative result to be in accurate. The paper relates a comparative quantitative analysis using standard and standardless methods in the determination of these elements. Standard method was done by plotting regression calibration graphs of the interested elements using BCS certified stainless steel standards. Different calibration plots were developed based on the available certified standards and these stainless steel grades include low alloy steel, austentic, ferritic and high speed. The standardless method on the other hand uses a mathematical modelling with matrix effect correction derived from Lucas-Tooth and Price model. Further
improvement on the accuracy of the standardless method was done by inclusion of pure elements into the development of the model. Discrepancy tests were then carried out for these quantitative methods on different certified samples and the results show that the high speed method is most reliable for determining of Ni and the standardless method for Mn.
XRF analysis was done on a local zircon samples and the result shows it has a high Fe, Th and U content. The high Fe content in Malaysian zircon had made the mineral to be classified as of a low-grade zircon. Presence of Fe in this mineral may be resulted from clay mineral coating found on the zircon surface. Chemical leaching technique was used for the removal of this Fe and the study also shows that a 600 o C heat pretreatment stage is important for the effectiveness of this process. Other parameters studied are the HCl concentration, leaching temperature and time. By using the optimum leaching parameters, the Fe content had been reduced to 0.049% and thus qualified it to be categorised as a premium grade zircon.
The paper relates a study on the development of an analysis procedure for measuring the gold coating thickness using EDXRF technique. Gold coating thickness was measured by relating the counts under the Au Lα peak its thickness value. In order to get a reasonably accurate result, a calibration graph was plotted using five gold-coated reference standards of different thicknesses. The calibration graph shows a straight line for thin coating measurement until 0.9μm. Beyond this the relationship was not linear and this may be resulted from the selfabsorption effect. Quantitative analysis was also performed on two different samples of goldcoated jewelry and a phone connector. Result from the phone connector analysis seems to agree with the manufacturer’s gold coating value. From the analysis of gold-coated jewelry it had been able to differentiate the two articles as gold wash and gold electroplated.
This work main aim is to study the analysis of slow neutrons which include thermal and
epithermal neutrons and also analysis on fast neutrons. The outcome from this work showed that
the comparison result between fast and slow neutrons. The safety assessment at reactor TRIGA
FUSFATI (RTF) is one of the main objectives of the work and there is a detailed discussion on it
which helped in accomplishing the task. Gamma Rays produced in this experiment was high and in
the experiment and it is realized that the shielding plays a vital role in the success of this
experiment which prevents all the radiations. From the results of the experiment it is realized that
these gamma rays are not suitable for the application of Boron Neutron Capture Therapy
(BNCT). However, these radiations are suitable for the application of Neutron Radiography (NR).
The study on this work will help in study of nuclear applications such as BNCT, NR, SANS etc.
These applications are using in medical and nuclear fields. The electronic device used in the
experiment to detect neutron is Neutron Spectrometer. The results from Neutron Spectrometer
and TLDs are very similar which showed that the experiment is a success. Numerical results were
compared with those available in literature for validation.
The joining of ceramic-metal could be done through a few techniques: brazing, diffusion bonding, friction welding etc. However, the mechanism of ceramic-metal joining was still not properly understood. In this study, alumina rod was bonded to mild steel rod via friction welding technique by using Al 1100 sheet as interlayer. The diameter of the rods was 10 mm. Friction pressure of 20 MPa and forging pressure of 40 MPa were used. Rotational speeds were maintained at 900 rpm and friction times of 2 to 20 seconds were applied. The joining strength was determined through four point bending test. The maximum bending strength, 240 MPa was obtained at the friction times of 20 seconds. Under optical microscope and SEM observation, the deformation of the aluminum interface was clearly obtained. Mechanical interlocking and close contact between the aluminaaluminum and aluminum-mild steel were observed at magnifications of 3000X. The strength of alumina-steel bonding is much dependent on the wettability of the alumina surface by the molten aluminum and the existing of mechanical interlocking between interlayer and sample materials.
The low resolution Automatic Picture Transmission (APT) data from the National Oceanic and Atmospheric Administration (NOAA) polar-orbiting satellites Advanced Very High Resolution Radiometer (AVHRR) is being received and recorded in real-time mode at ground receiving station in School of Science and Technology, Universiti Malaysia Sabah. The system is suitable for the developing and undeveloped countries in south and Southeast Asia and is said to be acceptable for engineering, agricultural, climatological and environmental applications. The system comprises a personal computer attached with a small APT receiver. The data transmission between the ground receiving station and NOAA satellites is using the electromagnetic wave. The relation for receiving and processing the electromagnetic wave in the transmission will be discussed.
Ceramic materials play key role in several biomedical applications. One of them is bone graft which is use in treating bone defect which caused by injury or osteoporosis. Calcium phosphates based ceramic are preferred as bone grafts in hard tissue engineering because of their chemical compositions are similar to the composition of human bone, superior bioresorbable and bioactivity. In this study, β-tricalcium phosphate (β-TCP) ceramic was synthesized by using sol-gel method. Phosphorous pentoxide (P2O5) and calcium nitrate tetrahydrate (Ca(NO3)2.4H2O) were used as calcium and phosphate precursors. The effects of calcination temperature on the synthesis powder were studied using the XRD, SEM-EDS and FTIR techniques. It was found that calcination temperature greatly influence the purity of the synthesized powders. The β-TCP was the dominant phase with the formation of α-TCP at calcination temperature from 600 to 800°C. Pure β-TCP was obtained at calcination of 900°C. As the temperature increased to 1000°C, the β-TCP was decomposed to for calcium phosphate oxide (CPO). The sol-gel method has some advantages over other methods, mainly its simplicity and ability to produce pure β-TCP at lower calcination temperature.
Ceramic foams are a class of high porosity materials that are used or being considered for a wide range of technological applications. Ceramic foam was produce by polymer replication method. In this process, commercial polymeric sponge was use as template, dipping with ceramic particles slurry, drying and then sintered to yield a replica of the original foams. The study was focus on the fabrication of different density of ceramic foams by varying the density of ceramic slurries (1.1876, 1.2687, 1.3653 and 1.5295 g/cm3). Properties of ceramic foam produced such as density was characterized accordingly to ASTM C 271-94 and porosity were characterized using Archimedes methods. Compressive and bending strength was performed accordingly to ASTM C1161-94 and C773-88 (1999), respectively. The morphological study was performed using Scanning Electron Microscopy (SEM) and EDX. Density of ceramic foams produced was about 0.5588 and 1.1852 g/cm3, where as porosity was around 26.28 and 70.59 %. Compressive and bending strength was increase from strength also increases from 2.60 to 23.07 MPa and 1.20 to 11.10 MPa, respectively, with increasing of slurries density from 1.1876 to 1.3653 g/cm3. The SEM micrographs show that the cells structure become denser as the slurries density increased. EDX proved that the ceramic used is porcelain. As a conclusion, increasing in slurries density produced ceramic foams with good mechanical properties such as compressive and bending strength and denser body.
The land area of Tanah Putih, Gua Musang, Kelantan (Malaysia) is well-known for its wealth in industrial mineral resources, especially aluminosilicate of feldspar and mica. Natural feldspar and mica were physicochemically characterized with regard to X-ray diffraction (XRD), nitrogen sorption analysis and transmission electron microscopy (TEM) techniques for qualitative and quantitative identification of feldspar and mica. They show a good crystallinity, high surface area and uniformity of mesoporous structures. For the purpose of this experiment, the aluminosilicate of feldspar was modified either by acid treatment, or grafting the silanol groups present with various functional groups including aminopropyl-, octyl-, vinyl-, mercapto- and glycidoxy-triethoxysilanes, or activation of pre-treated support with glutaraldehyde. These support derivatives were used for further utilization in the immobilization of lipase from Candida rugosa and resulted in various interaction mechanisms between enzyme and introduced supports. It seemed that the features of the functionalized feldspar surfaces provide a preferable environmental host to enable the adsorption of lipase via interfacial adsorption method. Lipase immobilization onto feldspar support were further confirmed by scanning electron microscopy (SEM) coupled with energy dispersive X-ray microanalysis (EDX), transmission electron microscopy (TEM) and infra-red spectroscopy (FTIR) techniques. Enhancement of protein loading (up to 8.22 mg protein/g support) and immobilization yield (up to 78%) were shown by modified feldspar-lipase derivatives compared to unmodified feldspar support.
Ageing management is one of the important safety factors to be implemented proactively throughout the lifetime of a research reactor. In order to continue the safe operation of a research reactor from the reactor safety standpoint, a systematic and methodical approach should be taken. In practice, ageing management programme is accomplished by integrating the existing programmes including maintenance, periodic testing and inspection and periodic safety reviews. Such approach will be a good platform for the reactor operation
and maintenance group to utilize data from existing maintenance programme to be incorporate into the ageing maintenance system. This paper will describe the ageing management programme for Reactor TRIGA PUSPATI (RTP).
The composite polymer films of polyvinyl alcohol/polypyrrole/chloral hydrate (PVA-PPy-CH) had been prepared. Effects of γ-rays on the electrical conductivity of the composite polymer films had been investigated by using Inductance Capacitance Resistance meter (LCR) meter at a frequency ranging from 20 Hz to 1 MHz. With the incorporation of chloral hydrate in the polymer sample, the conductivity increased indicates that it is capable to be used as dopant for polymerizing conjugated polymer. The electrical conductivity obtained increased as the dose increased, which is in the order of 10-5 Scm-1 indicates that γ-rays is capable to enhance the electrical conductivity of the composite polymer films. The parameter of s is in the range of 0.31 d s d 0.49 and obeyed simple power law dispersion ωs. The Scanning Electron Microscopy (SEM) micrographs reveal the formation of polypyrrole globules in polyvinyl alcohol matrix which increased as the irradiation dose was increased.
The composite polymer films of polyvinyl alcohol/polypyrrole/chloral hydrate (PVA-PPy-CH) had been prepared. Effects of J-rays on the electrical conductivity of the composite polymer films had
been investigated by using Inductance Capacitance Resistance meter (LCR) meter at a frequency
ranging from 20 Hz to 1 MHz. With the incorporation of chloral hydrate in the polymer sample, the conductivity increased indicates that it is capable to be used as dopant for polymerizing conjugated polymer. The electrical conductivity obtained increased as the dose increased, which is in the order of 10-5Scm-1 indicates that J-rays is capable to enhance the electrical conductivity of the composite polymer films. The parameter of s is in the range of 0.31 d s d 0.49 and obeyed simple power law dispersion Zs. The Scanning Electron Microscopy (SEM) micrographs reveal the formation of polypyrrole globules in polyvinyl alcohol matrix which increased as the irradiation dose was increased.
The hardcoat anodising process was done by using different concentration of H2SO4 from 0% to 20%. The 90 volt of anodising process was applied by using Al foil as cathode materials. The surface changes on PM Al-Mg resulted by hardcoat anodising was characterised by XRD measured. Surface hardness was measured by Micro-Vickers hardness machine. The experiment found different XRD pattern between anodised PM Al-Mg samples. The study was found by that the optimum value for H2SO4 concentration was 15 % H2SO4 and result 26 μm thickness, 5.07% of mass changes and HVN 105.4 hardness. The hardcoat anodising was affected to the XRD pattern for PM Al-Mg.
A study of wear behaviour on anodised PM aluminium matrix composites (AMC) reinforced with Saffil™ alumina short fibres was done. AMC was fabricated by powder metallurgy methods (PM) with using Al flake powders and Saffil™ alumina short fibres. AMC reinforced with 15 wt % Saffil¥ alumina short fibre was selected because it showed optimum mechanical and physical properties. Sulphuric acid anodising process was performed and the objective is to obtain suitable parameters of sulphuric acid concentration, anodising voltage and anodising time on MMC. The study of anodising process was carried out with various sulphuric acid concentrations (from 0 to 20 % volume), anodising voltage (10 V to 20 V) and anodising time (from 0 to 60 minutes) at room temperature. Scanning electron microscope (SEM) was used to investigate coating morphology and thickness. From the research, anodising voltage of 18 V and 15 % vol H2SO4 in anodising time of 60 minutes were suitable parameters for sulphuric acid anodising of this AMC. SEM showed the coating thickness around 20 Pm. From the reserch, it was found that H2SO4 anodising was able to give good coating to MMC.
Sodium silicate was used to synthesize silica fine particles at room temperature using non-ionic surfactant of triethanolamine (TEA), dissolution salt and precipitating agent. The experiments were conducted by different composition of precursor material, nonionic surfactant and dissolution salt concentrations through the sol-gel process. Various particle sizes in the range 100-300nm were synthesized. The particle size of silica powders were analyzed via Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-ray Analysis (EDAX), X-Ray Fluorescence (XRF), and Fourier Transformation Infrared (FTIR). The result has demonstrated that the particle size can be controlled by changing the ratio of non-ionic surfactant and dissolution salt or the sodium silicate concentration.
Batu Reput’ is primary sediment mineral and abundantly found in Perlis. Perlis is one of the major producers of ‘Batu Reput’ in Malaysia that content large deposit of high-purity dolomite [CaMg (CO3)2]. Pure samples of ‘Batu Reput’ recently explored in the Koperasi Rimba Mas Padang Besar Quarry were investigated for their physical, chemical and mineralogical composition. SEM and XRD analysis methods were applied. The potential of ‘Batu Reput’ as a raw material in fertilizer production was investigated in this paper.
The geometry of reactor core, thermal column, collimator and shielding system for BNCT application of TRIGA MARK II REACTOR were simulated with MCNP5 code. Neutron particle lethargy and dose were calculated with MCNPX code. Neutron flux in a sample located at the end of collimator after normalized to measured value (Eid Mahmoud Eid Abdel Munem, 2007) at 1 MW power was 1.06E8 n/cm2/s. According to IAEA (2001) flux of 1.00E9 n/cm2/s requires three hours of treatment. Few modifications were needed to get higher flux.
Thermal neutron beam from thermal column was selected for a Boron Neutron Capture Therapy
(BNCT) system utilizing the Malaysian TRIGA MARK II reactor. Determination of shielding
materials for fast and epithermal neutron was conducted. The materials selected were polyethylene,
paraffin and water. For gamma-ray shielding, lead was used. The objective of this paper is to present
the simulation and verification of an optimal design of BNCT collimation at a beam. line viewing the
thermal column. A collimator was made from polyethylene pipe with 8 cm of diameter filled with
paraffin.
Cement and concrete has been widely used as shielding material in reactor nuclear in order to minimize exposure to individuals. In this paper we present boron based concrete as neutron shielding for nuclear reactor applications. Concrete specimens with dimension of 10x10x10 cm were used and irradiated with neutron radiation of 252-californium. Characterization of physical, mechanical and radiation attenuation properties of concrete were carried out. The results show that the shielding performance is better than ordinary concrete. From the result, we confirmed that the performance of the concrete/boron carbide is suitable for practical use.