Advanced Materials Research Vol. 845

Abstract: Glycerol is the main by-product of biodiesel production and during the trans-esterification reaction, about 10 wt % of glycerol is produced. In this study, different amount of Ni was loaded on HZSM-5 and tested for the conversion of glycerol to hydrogen. The studies were also conducted at different reactor temperature of 450, 500, 550, 600 and 650°C respectively. The structural characterization of the catalyst was carried out using the XRD. It was found that, the addition of 15 wt % of nickel loaded on HZSM-5 shows the highest glycerol conversion of 98.54%. In addition, it produces the highest yield of hydrogen gas operated at reactor temperature of 600°C.

Abstract: The releases of harmful ions from cobalt based alloy to host tissues have raised significant health concerns. Carbon contents in this alloy may influence ions release but has yet investigated. It is hypothesized that carbon contents in this alloy will help the formation of oxide layer during thermal oxidation process and hence reducing the release of Co/Cr ions after implantation. In this study, Co-Cr-Mo alloy with carbon concentrations of 0.03% and 0.24% were oxidized at 1050°C for 3 hours under atmospheric condition. The oxidized substrates were characterized under FESEM and subjected to circulating immersion test in simulated body fluid (SBF) for 21 days. Metal ions release was measured using inductively coupled plasma-mass spectrometry (ICP-MS) at day 0, 7, 14 and 21. Oxidized high carbon samples show denser and a more uniform oxide layer than samples with low carbon contents. It is found that compact oxide structure promotes less metal ions release during immersion.

Abstract: The effect of seeding using different mixtures of diamond and silicon carbide (SiC) powders on the adhesion strength of hot-filament chemical vapor deposition (HFCVD) diamond coating on WC-6% Co substrates was studied. Diamond powders with the average grain size of 0.5 μm mixed with various concentrations of SiC powder of 175μm average grain size were employed. Diamond layers were deposited using a production unit of HFCVD technique. The diamond film morphology and the diamond quality were examined using field emission scanning electron microscope (FESEM), X-ray diffraction (XRD) and Raman spectrometer respectively. It was found that the diamond morphologies produced and the qualities were almost the same for all the seeding mixtures of pretreatment. With the blasting technique employed to determine the adhesion strength it was found that the highest diamond film adhesion strength was achieved from the seeding of a mixture of diamond with 5g/l SiC powder.

Abstract: In recent years, there has been an increasing interest on energy saving in building sector.Passive cooling is considered the best strategy for improving the indoor thermal conditions and comfortwith lowest cost energy usage. In air-conditioned era, however, many designers have fully forgotten that the main objective of building thermal comfort is not to cool the whole space but rather the resident of the building with the least energy consumption. This investigation is about discussing some of the available passive cooling strategies based on experimental investigations. Results from this study showed that building materialsaffect the indoorair temperature, which in turn willaffect the indoor thermal comfort. Design strategies more suitable under tropical humid climatic conditions were suggested.

Abstract: The objective of this work was to provide the efficiency of visible light assisted Fenton oxidation for the treatment of natural gas industry wastewater containing DIPA. Different parameters were studied for the degradation of DIPA including light intensities, H₂O₂ and initial DIPA concentrations. From the results it was found that the optimum hydrogen peroxide concentration was 1.0 M for both light intensities. Whereas, for different DIPA concentrations depending on the light intensities, 300 W gave the higher COD removal (60.64%), which was concluded as the more efficient light source compared to 500 W.

Abstract: This paper presents experimental study on short-term breakdown of silicone rubber based nanocomposites with different silicone dioxide (SiO₂) nanofiller loading by focusing on the effect of electrical tree. The objective of this study was to investigate the ability of SiO₂ nanofiller to inhibit the growth of electrical tree in silicone rubber until breakdown. Samples of silicone rubber based nanocomposites (three samples were filled with 1wt%, 2wt% and 3wt% of SiO₂ respectively whereas the forth sample was unfilled silicone rubber), were used in this experimental study and two parameters such as electrical tree initiation voltage and breakdown time were measured. Based on the obtained results, the sample with the highest SiO₂ loading has shown the highest tree initiation voltage and the longest breakdown time. Therefore, this makes SiO₂ a promising material to be used as fillers in polymeric insulations for the purpose of retarding electrical tree growth.

Abstract: Aluminium used in beverage containers or cans is a sustainable material and can be recycled repeatedly. In Malaysia, the activities of collecting aluminium beverage cans for recycle normally involve a process of compressing aluminium cans manually in order to reduce storage space. The cans compression process is very time consuming and unproductive. In addition, there is no standard aluminium cans compressor tool that available in the market currently. As such, this paper aims to identify users requirements on the potential tool that could be used to compress aluminium beverage cans, follows by transform the important users requirements to a set of design criteria for the development of aluminium cans compressor. In line with this, six important factors that influence users purchase decision on household product were identified from literature review. The important factors were adapted into a questionnaire to collect and identify users preferred requirements on aluminium cans compressor via Voice of Customer technique. Subsequently, Pareto analysis and t-test were applied to define the most important and significant users requirements that influenced user purchase decision. As a result, a list of important users requirements is generated, which is also served as the design criteria for the development of a new aluminium cans compressor. Finding from the paper suggested that the most important design criteria for the potential aluminium cans compressor are consisted of safety, cost, performance and reliability requirements.

Abstract: The utilization of rice husk as an alternative fuel for the power plant in Indonesia is still under study. In present, steam power plants in Indonesia are still using coal fuel. This study was conducted to obtain data on the development potential of rice husk within 12 years duration. The potential of rice husk for each province was obtained by analyzing the rice production of 22 provinces that have rice production greater than 1 million tons per year. The study shows that the potential of rice husk and potential electrical energy increased by about 36.8% within 12 years or an average increase of around 3.1% per year. For the potential of rice husk in 22 provinces, the total gain was estimated 12.76 × 10⁶ tons which is equivalent to 6.62 × 10⁶ tons of coal or equivalent to 3.68 × 10⁶ tons of oil. The available capacity of power plants is around 5,664 MW with the potential of electric energy is around 49,622 GWh. This potential is equivalent to 50% of the energy needs of coal in Indonesia in 2011, which was about 99,312 GWh. In conclusion, rice husk is indeed potential to be used as an alternative fuel in power plants thanks to its increasing yearly production and ability for distribution to all provinces in Indonesia.

Abstract: This paper shed lights on the effects of knowledge spillover on innovation performance of firms in high-tech cluster. There is more knowledge spillover in clusters than other area. Firms in clusters have higher absorptive ability than firms outside of cluster, there is also interaction between firms absorptive ability and different sources of knowledge stock. Knowledge spillover from cluster internal knowledge stock is more important than that from external knowledge stock.

Abstract: This paper presents rationality behind the establishment of an ELVs management system in Malaysia, in relation with the development of automotive industry in this country. Upon reviews on latest publications, there are currently three conditions of ELVs treated in Malaysia which are used on road, left abandoned and dumped at landfill. These improper treatment and management of ELVs certainly will give negative effects to the country, which are explained in environment, economic and social aspects. Subsequently, a survey will be conducted to obtain estimated percentage of each ELV condition, and the survey results will be the basis towards establishing an ELVs management system in Malaysia.