Abstract

The effects of formulation factors on the pencil hardness and thermal degradation properties of a bio-based coating derived from Talisay (Terminalia catappa) seed oil extract were studied. The bio-based coating was prepared using thiol-ene coupling via photopolymerization. Pencil hardness measurements of the film coating were performed and results show that increasing Oil/MDI ratio decreases the hardness of the film coating. Furthermore, thermogravimetric measurements show that the film coating is thermally stable up to 300℃.

Index Terms

Bio-based, coating, photopolymerization, hardness, TGA

Abstract

The flexural capacity and the midspan deflection of the unstrengthened and strengthened I–beam samples with CFRP fastened with bolts under 4 – point load test are investigated in this paper. Twenty (20) steel beam specimens were tested – one (1) sample group of unstrengthened beams, and the remaining three (3) sample groups of strengthened beams with 4, 6, and 8 bolts, respectively. Aside from the number of bolts and the development length of CFRP, parameters considered were held constant. Compared to unstrengthened beams, the load capacities of strengthened beams with CFRP anchored with 4 bolts, 6 bolts, and 8 bolts, significantly increased by about 23.25 %, 19.03%, and 14.69%, respectively. However, the increase in the number of bolts has no significant contribution to the load capacity of the strengthened beam. Moreover, as compared to unstrengthened beams, the amounts of deflection of strengthened beams were significantly reduced due to an increase in the moment of inertia. Overall, the addition of CFRP brought about positive effects in strengthening the structural steel I – beams.

Index Terms

strengthened beams, carbon fiber reinforced polymer, flexural capacity, midspan deflection

Abstract

Furfural is the product of the hydrolysis of pentosan-rich materials which can normally be found in biomass. Pentosans from coconut shell, coconut husk, pineapple bagasse, and water hyacinth, which are available agricultural wastes in the country, were used in this study. The laboratory synthesis of furfural was done by acid-catalyzed hydrolysis. The acid hydrolyzes were carried out at 180°C using dilute (0.2 M) sulfuric acid for different hydrolysis times. Results show that the study was successful in synthesizing furfural from the four different agricultural residues used. Furthermore, it was found out that furfural yield increases as digestion time increases, but only up to a certain hydrolysis time, different for every raw material, for which the maximum average percent mass furfural yield can be obtained. After which, a decrease in mass yield will be noticed.

Index Terms

furfural, pentosan, acid hydrolysis, digestion time, agricultural waste

Abstract

This study reports the use of glass cullet in a talc-based ceramic batch formed by starch consolidation technique. Three talc-based ceramic slurries consisting of red clay, glass cullet, and talc were formulated and dispersed at 70 wt% ceramic solid mixed with 16 wt% cassava starch. Ceramic disks, test bars, and tiles were successfully consolidated in acetate molds. The firing of samples was done at 900, 1000, 1050 and 1100 °C with a one-hour soaking and a heating rate of 5 °C/min. The effects of increasing the proportion of talc with decreasing glass cullet in ceramic batches and sintering temperatures were studied in terms of physical and thermal properties. XRD analyses of fired samples mainly revealed ceramic phases such as diopside, cordierite, protoenstatite, cristobalite and tridymite. A highest thermal shock resistance was determined at about 3.67 MPa after 10 cycles for a ceramic body composition fired at 1050 °C, with a composition of 0.06 K2O, 1.00 Al2O3, 0.02 TiO2, 4.11 Na2O, 0.18 Fe2O3, 13.71 SiO2, 1.20 CaO, and 4.33 MgO. The promising properties of the talc-based bodies enable the material design for thermal application.

Index Terms

Talc-based ceramics, Cordierite, Red clay, Starch consolidation

Abstract

Due to the unsustainable use of fossil fuels, the use of renewable energy such as wind energy takes the spotlight for power generation. However, assessment for finding a good wind resource potential poses a tough challenge for the researchers and modelers. Weather Research and Forecasting Model, a state-of-the-art mesoscale numerical weather prediction system, can identify a wind resource potential using a numerical representation based on the current weather measurement. A sensitivity analysis was carried out with the selection of January and July as the representative for the dry and wet season in the Philippines. Two sets of parameters were tested. For January, Pleim-Xiu-ACM2-Pleim-Xiu exhibited lower values for different error metrics used in this study (Mean Absolute Error, Root Mean Squared Error, Standard Deviation Error, and Bias). For July, MM5-YSU-Noah showed better results. Using Geographic Information System (GIS) a wind map was also created for the study area (Mindanao). Based on the outcome of the whole simulation, the area of Tubod, Lanao del Norte showed good wind resource potential.

Index Terms

Geographic Information Systems, renewable energy, Weather Research and Forecasting model, Wind resource assessment

Abstract

With the rising environmental problems associated with the use of conventional energy sources from fossil fuel and the decrease of the cost of renewable energy technologies, micro-grid powered by micro-hydropower and photovoltaic systems has become a very popular choice for remote area electrification. However, micro-grid systems still face several issues with stability due to the variations of energy demand at different periods and the unpredictable behavior of distributed energy sources. This paper presents a micro-grid design powered by renewable energy sources and the simulation of its transient stability when subjected to three-phase faults at different locations. A Graphical User Interface (GUI) that displays the performance and stability of the micro-grid was also created. The results of this study can be utilized for future decision making in the electrical planning of the micro-grid. The critical clearing time data can be used in the selection of proper protective equipment and relay time settings.

Index Terms

Equal area criterion, micro-grid, renewable energy, transient stability

Abstract

Flooding has been among the greatest concerns in the Philippines, especially in lowland areas surrounded by high elevations like in Kapatagan, Lanao del Norte. The flash flood that hit the municipality last January of 2014 has led to devastating effects on the economy as sustained rainfall causes flash floods and overflowing of water from drainage channels. As urbanization sprawl in the municipality, surface runoff from a heavy rainfall inundated most of the lowland barangays. Thus, this study aims to design a flood control channel along Matimos Creek that will serve as the main drainage outlet of floodwaters in the area and assess the effectiveness of the design using HEC-RAS 2D software version 5.0.6. Excess precipitation and design peak discharge were obtained from the simulation in HEC-HMS. The peak discharge values were used to calculate the most efficient trapezoidal channel cross-sections. The proposed cross-sections were integrated into the HEC-RAS 2D model through terrain modification. Both unmodified and modified terrains were then compared to assess the effectivity of the proposed channel design. Based on the results, it is segment B that has the highest peak discharge and therefore has bigger corresponding dimensions compared to the other segments. It showed that the design is capable of reducing the inundated area and the flood depth, especially in the areas surrounding the channel.

Index Terms

flood control channel, HEC-RAS 2D, peak discharge