Stabilization of Empty Fruit Bunch (EFB) Derived Bio-oil

Bio-oil is a promising alternative source of energy which can be produced from empty fruit bunch (EFB). Bio-oil comprises a mixture of highly oxygenated compounds, carboxylic acids and trace water. Bio-oil can be used as a substitute for conventional fuels after it is upgraded. However, bio-oil can react through many chemical reactions such as polymerization and this will lead to the increase in viscosity of bio-oil during storage. Thus, this research project will explore on the stabilization of empty fruit bunch derived bio-oil. The bio-oil that will be used in this research is produce from the catalytic pyrolysis of EFB. The optimum reaction condition used is catalytic pyrolysis of EFB using 5 wt% of H-Y catalyst at reaction temperature of 500 °C and nitrogen flow rate of 100 ml/min. This operating condition is able to obtain the maximum yield. There are 2 type of methods will be used in this research to improve the stability of the bio-oil: addition of anti-oxidants and addition of solvents. For the addition of anti-oxidants, three kinds of anti-oxidants which are propyl gallate (PG), tert-butyl hydroquinone (TBHQ), butylatedhydroxyanisole (BHA) and calcium chloride salts (CaCl2) are added to bio-oil in the amount of 1000 ppm. On the other hand, the second methods will use 10 wt% of solvents including acetone, ethanol 95 %, and ethyl acetate to increase the bio-oil’s stability. All the test samples are subjected to accelerated aging involving exposure to high temperature of 80 oC for 7 days. The properties of samples which are chosen as the indicator of the aging are viscosity, water content and acidity. This progress report contains 6 chapters. Chapter 1 will discuss the introduction on the background, problem statement, objective and the scope of study for the project, relevancy of the project and feasibility of the project within the scope and time frame. A detailed literature review will be discussed in chapter 2. Besides, chapter 3 will focus on the research methodology and also the key milestones for the project in order to give a detail overview of the whole research project. Chapter 4 will be the results and discussion for the research project. Chapter 5 and 6 are the conclusion and references respectively

Deep Learning for Audio Signal Processing

Given the recent surge in developments of deep learning, this article provides a review of the state-of-the-art deep learning techniques for audio signal processing. Speech, music, and environmental sound processing are considered side-by-side, in order to point out similarities and differences between the domains, highlighting general methods, problems, key references, and potential for cross-fertilization between areas. The dominant feature representations (in particular, log-mel spectra and raw waveform) and deep learning models are reviewed, including convolutional neural networks, variants of the long short-term memory architecture, as well as more audio-specific neural network models. Subsequently, prominent deep learning application areas are covered, i.e. audio recognition (automatic speech recognition, music information retrieval, environmental sound detection, localization and tracking) and synthesis and transformation (source separation, audio enhancement, generative models for speech, sound, and music synthesis). Finally, key issues and future questions regarding deep learning applied to audio signal processing are identified.Comment: 15 pages, 2 pdf figure

Misconceptions in the teaching of chemistry in secondary schools in Singapore & Malaysia

Misconceptions are erroneous perceptions of what is universally accepted as physical laws that have been experimentally tested to date. There are many sources of misconceptions in the teaching of Chemistry and the origins of some of these misconceptions are discussed with reference to Malaysian and Singapore students. Surveys on students in the form of questionnaires, and Chemistry teachers having to conduct microteaching sessions with peer evaluations, have been shown to be effective tools in identifying some misconceptions among students and teachers. Many of these misconceptions are common with students of Chemistry world-wide arising mainly from text books and our general perceptions of things through multi media. Surveys in the form of questionnaires and micro-teach have been conducted to identify both students? and teachers? perceptions. Some of these misconceptions identified are derived from peers, family members within our different ethnicity and cultures. This is particularly important in this region of the world where there is so much diversity in language and culture. Malaysia, for example, has used English as the medium of instruction, reverted to Bahasa Malaysia and back again to English in the teaching of Science. This will invariably bring about a shift of conceptual visualization as we change from one language to another. The surveys also highlighted the importance of peer evaluation in an attempt to make teachers more aware of their misconceptions. The paper is by no means exhaustive and hopes to provide a general guideline for teachers of Chemistry in the region, to be aware of such misconceptions during their teaching of the subject

Differentiation of body fat composition between skinfold caliper (SKF) and bioelectrical impedance analysis (BIA) methods among professors

Body fat composition reflected by body fat percentage (BF%) is one of the important components in disease risk evaluation. Among the methods available to measure BF%, skinfold calipers (SKF) and bioelectrical impedance analysis (BIA) are the most commonly used. The study was conducted to evaluate the difference in body fat composition measurement between SKF and BIA methods among professors. This study analyzed secondary data from the health evaluation of Universitas Padjadjaran (UNPAD) professors. This study involved 72 professors (50 male, 22 female) after fitted into the inclusion and exclusion criteria. BF% was measured among UNPAD professors using SKF and BIA. After obtaining agreement by Bland-Altman Plot, the data were analyzed by muliple paired-t test according to gender, physical activity level and body mass index (BMI) categories. The study showed no significant difference in BF% between SKF and BIA in overall population, between gender and physical activity level (p>0.05). For BMI, the only category that showed significant difference in BF% between the 2 methods was obese I group (p=0.001). In conclusion, there is no significant difference in BF% between SKF and BIA methods according to gender, physical activity levels and BMI categories except for obese I group

A Molecular Simulation Study of Silica/Polysulfone Mixed Matrix Membrane for Mixed Gas Separation

Polysulfone-based mixed matrix membranes (MMMs) incorporated with silica nanoparticles are a new generation material under ongoing research and development for gas separation. However, the attributes of a better-performing MMM cannot be precisely studied under experimental conditions. Thus, it requires an atomistic scale study to elucidate the separation performance of silica/polysulfone MMMs. As most of the research work and empirical models for gas transport properties have been limited to pure gas, a computational framework for molecular simulation is required to study the mixed gas transport properties in silica/polysulfone MMMs to reflect real membrane separation. In this work, Monte Carlo (MC) and molecular dynamics (MD) simulations were employed to study the solubility and diffusivity of CO2/CH4 with varying gas concentrations (i.e., 30% CO2/CH4, 50% CO2/CH4, and 70% CO2/CH4) and silica content (i.e., 15–30 wt.%). The accuracy of the simulated structures was validated with published literature, followed by the study of the gas transport properties at 308.15 K and 1 atm. Simulation results concluded an increase in the free volume with an increasing weight percentage of silica. It was also found that pure gas consistently exhibited higher gas transport properties when compared to mixed gas conditions. The results also showed a competitive gas transport performance for mixed gases, which is more apparent when CO2 increases. In this context, an increment in the permeation was observed for mixed gas with increasing gas concentrations (i.e., 70% CO2/CH4 > 50% CO2/CH4 > 30% CO2/CH4). The diffusivity, solubility, and permeability of the mixed gases were consistently increasing until 25 wt.%, followed by a decrease for 30 wt.% of silica. An empirical model based on a parallel resistance approach was developed by incorporating mathematical formulations for solubility and permeability. The model results were compared with simulation results to quantify the effect of mixed gas transport, which showed an 18% and 15% percentage error for the permeability and solubility, respectively, in comparison to the simulation data. This study provides a basis for future understanding of MMMs using molecular simulations and modeling techniques for mixed gas conditions that demonstrate real membrane separation

REPRODUCIBILITY OF NATURAL RESOURCES FOR THE SYNTHESIS OF LOW TRANSITION TEMPERATURE MIXTURES (LTTMS)

LTTMs are combinationsof hydrogen bond donors(HBDs) and hydrogen bond acceptors(HBAs) as a new class of green solvents which aim to overcome the limitation of ionic liquids while sharingsome of theiradvantages. The materialsused as HBDsweremalic acidsextracted from cactus, papaya, and luffa cylindricawhile HBAs were L-proline, L-histidine, glycine, and choline chloride, all of which existednaturally in living organismsor plants. Compatibilityof different combinations of HBD and HBA to form LTTMsand varying their molar ratio were the subjectsof interest in this project. A biopolymer solubility test was carried out on all LTTMs to identify the best performed LTTM and utilize it in oil palm empty fruit bunch biomass pretreatment. For LTTMssynthesis, onlyhistidine was incompatible with malic acid. The solubility screening test showed that combination of cactus and proline with a molarratio of 1:1 (CP 1:1) is the most effective LTTM in dissolving lignin (12.87 wt%), followed by luffa cylindrica :proline 1:1 (11.53 wt%). FTIR analysis was carried out and proved the existence and formation of a hydrogen bond within the solvent structure. The most critical disadvantage of LTTMs was the thermal instability due to its weak hydrogen bonding. CP 1:1 showedthe similarresult in biomass pretreatment to the biopolymerssolubility screening test, which is around 12 wt% of lignin solubility. This work provides an alternativemethod of biomass pretreatment for lignin extraction