bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation of Interacting Channels in Decentralized Control Systems Using Instrumental Variables Method
Authors: Rahim Mohamed , Ramasamy M. , Tufa Lemma Dendena , Faisal A.
Published: September 2014

This paper describes the use of partial correlation based instrumental variables method for the identification and isolation of weak interaction dynamics between subsystems in decentralized control systems. Unlike the available methods based on the ordinary least square, the proposed method clearly discriminates the interaction channels that have significant contribution to the interconnected subsystem from the ones which do not by reducing the model error that arises due to the process inputs correlation. The efficacy of the proposed method is illustrated through a case study.
Evaluation of Electrical Capacitance Tomography Thresholding Techniques for Void Fraction Measurement of Gas-Liquid System
Authors: Lock Irene Sow Mei , Ismail Idris B. , Abdullah Bawadi , Shafquet Areeba
Published: September 2014

An analysis on the void fraction measurement for binary phase gas-liquid dielectric materials inside an Electrical Capacitance Tomography (ECT) sensor has been performed on the tomogram images by using different thresholding techniques. The analysis is pertinent to improve the accuracy of the application of thresholding technique for void fraction measurements in pipelines and reactors since the currently available information is limited in terms of accuracy. This preliminary investigation was performed to evaluate the accuracy of three different thresholding algorithms: Otsu’s, Niblack’s and Kuo’s Method based on the void fraction measurement for a binary phase oil-air system. The experimental and image processing analysis enables one to determine the optimal threshold method by selecting the threshold algorithm which produces the highest accuracy and consistency in the void fraction measurement as compared to the actual value.
Comparison of Image Processing Methods for the Detection of Particle from Digital Hologram
Authors: Khanam Taslima , Rashedi Ahmad , Chowdhury Sujan , Asundi Anand Krishna
Published: September 2014

Two image processing methods for the detection of particle based on digital holography are presented and compared. The image processing methods are developed based on edge detection and threshold based segmentation. The proposed methods have been applied on reconstructed images of holograms of ceramic beads and certified microspheres. Particle size distribution obtained for both methods are found to be in good agreement with the actual size, but the processing speed for threshold based detection has found to be faster in compared to the edge detection method.
An Investigation into the Need of Process Safety Management (PSM) in the Palm Oil Industry
Authors: Kamarden Hamidah , Kidam Kamarizan , Hashim Haslenda , Hassan Onn
Published: September 2014

Palm oil industry (POI) is one of the major industries in Malaysia that contribute more than half of the Malaysia’s export value. Hence, the development of the industry also includes the well-being of the workers in the industry. As a consequence, the POI must adhere to several laws that provide protection for the workers’ safety and health such as OSHA 1994 and availability of guidelines to safety and health management such as OHSAS 18001. However, in terms of process safety, the POI is way lacking behind despite several incidents that show that POI as well is susceptible to process failures that lead to disastrous accidents. Process safety management has been successfully implemented in the chemical process industry (CPI) which is driven by the fact that the process is high risk with the utilization of hazardous materials and likelihood of fire and explosion. Hence, by comparison, it is found that these two industries has some similarity in terms of hazards, however the risk is found to be lower in the POI as compared to the CPI mainly because of the more hazardous materials that are involved in the CPI.
Optimization of Condensate Fractionation Unit Using Response Surface Methodology
Authors: Ibrahim Mohammad Taufik , Yusoff Nooryusmiza
Published: September 2014

Response Surface Method involving central composite design is employed to determine the optimal configuration of nine factors for maximizing the profit of a Condensate Fractionation Unit. When compared with the results from the base case and Taguchi method, the result from RSM shows higher profits by 33.1% and 1.16%, respectively. A further benefit of 0.64% is noticed when three insignificant factors were removed from the nine-factor experiment due to interactions between factors.
Preparation and Characterization of Hydrophobic Silica Zirconium Nanoparticles
Authors: Ellateif Tayseir M. Abd , Mitra Saikat , Murugesan T. , Azizli Khairun Azizi
Published: September 2014

Hydrophobic silica nanoparticles were synthesized by silica sols modified with different percentage of zirconium sol using liquid modification. The hydrophobicity test demonstrated that silica zirconium nanoparticles are more hydrophobic as they showed 1% to 5% weight gain compared to 8% for pure silica nanoparticles. The synthesized silica nanoparticles were characterized using different techniques to investigate the effect of zirconium modification on silica nanoparticles characteristics. Structure and composition of unmodified silica nanoparticles and modified one were studied using FTIR; the results showed that the zirconium oxide was anchored to the surface of silica nanoparticles. TEM and BET analysis showed that the percentage of zirconium added to silica had distinct effect on the particle distribution and surface area of silica nanoparticles.
Fabrication and Characterization of Facilitated Transport Membrane for Gas Separation
Authors: Nasir Rizwan , Mukhtar Hilmi , Man Zakaria
Published: September 2014

The new membrane material containing facilitate transport medium to enhance the performance of gas separation membrane has been fabricated by using monoethanolamine (MEA) as a fixed carrier with different concentration (5 & 10 wt. %) by using the solvent evaporation method. The developed membranes were characterized by using Field Emission Electron Microscope (FESEM), Fourier Transform Infrared (FTIR), and Thermo-Gravimetric Analysis (TGA). The developed membranes were found nonporous and dense in structure.
Comparative Study of Linear Co-Volume Based Mixing Rules for Equation of State/ Excess Gibbs Energy (EOS/GE) Models for CO2 – MEA and CO2 – MDEA Systems
Authors: Suleman Humbul , Maulud Abdulhalim Shah , Man Zakaria
Published: September 2014

With the advent of Equation of State/ Excess Gibbs Energy (EOS/GE) models, the linear co-volume based mixing rules have gained vast importance for predicting multi-component VLE for polar mixtures. Owing to their inherent ease of calculation and good prediction abilities, these mixing rules have been applied in extension, to a variety of systems especially for CO2-H2O-alkanolamine systems. However, no comparative study is available to select appropriate mixing rule for prediction of thermodynamic properties. In this study, pressure prediction of various linear co-volume mixing rules has been compared for CO2 – MEA and CO2 – MDEA systems, while effects of activity coefficients and process parameters have been kept constant. The infinite pressure mixing rules have heavily under – predicted and approximate zero reference pressure mixing rules have over – predicted, but latter are valid for low and medium pressure ranges. The linear combination of Vidal and Michelsen (LCVM) mixing rule have good predictions at high pressures.
Impact of Gas Phase Composition on Gas Hydrate Process for Carbon Dioxide Capturing from Gaseous Mixtures
Authors: Partoon Behzad , Sabil Khalik Mohamad , Lau Kok Keong
Published: September 2014

Hydrate based technology is a promising new process for separation of Carbon dioxide from different gas mixtures. The process is claimed to be less energy intensive, green and low technology. In this article effect of composition on the efficiency of such process is discussed. CSMGem software is used for analysis. Results shows that gas phase composition have important impact on the efficiency of process.
Effect of Superficial Gas Velocity on the Separation Efficiency of Inline Horizontal Swirl Tube Separator
Authors: Mellon Nurhayati , Azmi Mohd Shariff
Published: September 2014

The use of compact, inline separator has gain interest in the effort of reducing the size of topside facilities to reduce the capital cost associated with natural gas exploration. This paper discusses the effect of superficial gas velocity on the separation performance of an inline horizontal swirl tube separator. In this study, the superficial velocity is varied from a minimum of 5 m/s up to a maximum velocity of 12 m/s at different operating pressure. The pressure is varied from 40, 50 and 60 bars, corresponding to different centrifugal force on the incoming gas stream. Results shows that the best separation performance is achieve at higher operating pressure, in this case at 60 bar, regardless of the incoming fluid velocity and liquid load (of up to 30% by mass).
Separation of Naphthenic Acid Using Hydroxide Based Ionic Liquids
Authors: Shah Syed Nasir , Mutalib Mohammed Ibrahim Abdul , Pilus Rashidah Binti Mohd , Lethesh Kallidanthiyil Chellappan
Published: September 2014

Isolation of naphthenic acid from model oil using hydroxide based ionic liquid was investigated. A detailed de-acidification study at different temperatures and different ionic liquid/model oil was performed and the content of naphthenic acid before and after extraction was calculated. The ILs containing hydroxide anions has the potential to completely deacidify model oil having high TAN with extremely low ionic liquid /oil ratio.
Phase Diagram of an Aqueous Salt-Polymer System Composed of Poly Ethylene Glycol 4000 + Na3C6H5O7+ H2O
Authors: Hanaei Hengameh , Murugesan Thanabalan
Published: September 2014

Liquid−liquid extraction for the poly ethylene glycol (PEG) + Na3C6H5O7 + H2O system, with PEG of molecular weight 4000, have been measured at 300.15 K. Phase diagram behavior and tielines for PEG4000 have been studied and the effects of molecular weight of PEG 2000,4000,6000 on the binodal curve was investigated. In comparing to literature it was found that an increase in molecular weight of PEG shifted the binodal curve to lower PEG and salt concentrations. The ATPS's studied may be used in separation of protein and other compounds.
Separation of Benzene and Cyclohexane with Mixed Solvent Using Extractive Distillation
Authors: Richard Bradley , Bustam Mohammad Azmi , Gonfa Girma
Published: September 2014

Isothermal Vapour-liquid equilibrium for cyclohexane (1) + benzene (2) binary system, cyclohexane (1) + benzene (2) dimethylformamide (3) ternary system and cyclohexane (1) + benzene (2) dimethylformamide (3) + cosolvent (4) quaternary systems were obtained. The effects of cosolvents (diethyl glycol, dimethylsulfoxide, N-methylformamide) on the performance of dimethylformamide in benzene-cyclohexane separation were studied. The result shows the selected cosolvents suppress the effectiveness of dimethylformamide. The result also shows that the ratio of cosolvents to dimethylformamide affects the separation factor.
Physiochemical Properties of Pyrolysis Oil Derived from Fast Pyrolysis of Wet and Dried Rice Husk in a Free Fall Reactor
Authors: Naqvi Salman Raza , Uemura Yoshimitsu , Osman Noridah Binti , Yusup Suzana , Nuruddin Mohd Fadhil
Published: September 2014

Rice husk is considered as a massive agricultural lignocellulosic biomass residue for the production of bio-based fuels and chemicals products. The purpose of this study is to investigate the physiochemical properties of the pyrolysis-oil derived from wet and dried rice husk fast pyrolysis process. The experiments were performed in a drop type fixed-bed pyrolyzer at the pyrolysis temperature of 350 to 600 °C. The products, char, pyrolysis-oil and gas, yield are investigated. The pyrolysis-oil derived from dried rice husk contained higher Carbon and Hydrogen and less oxygen contents than the pyrolysis-oil obtained from wet rice husk. FT-IR results showed the oxygenated compounds present in both pyrolysis-oil. The pyrolysis oil from dried rice husk has higher concentration of hydrocarbons as compared to wet rice husk pyrolysis-oil. The dried rice husk pyrolysis-oil produced more phenols and less carboxylic acid as compared to wet rice husk pyrolysis-oil at 500 °C. More volatile released in dried rice husk conversion produced more volatile compounds. These findings suggest that the original moisture present in biomass samples is the major influencing parameter on the thermal degradation of biomass during fast pyrolysis process.
Fast Pyrolysis of Oil Palm Kernel Shell in a Fluidized Bed Reactor: The Effect of Biomass Size on the Yields of Pyrolysis Products
Authors: Uemura Yoshimitsu , Norizan Ali , Afif Hafizah Ahmad , Osman Norridah , Omar Wissam N. , Abdullah Bawadi , Tsutsui Toshio
Published: September 2014

This study investigates the effect of biomass size on the yields of char, liquid (organic compounds and water) and gas for fast pyrolysis of palm kernel shell (PKS). Fast pyrolysis was carried out in a fluidized bed reactor of 108 mm in internal diameter operated at 450 °C using three different sizes of palm kernel shell (0.325, 0.75 and 1.5 mm). In specific the effect of biomass size on the yields of known and unknown organics in bio-oil was mainly investigated. The major organics include acetic acid, phenol and furfural. The minor ones include 2-methylphenol, 4-methylphenol, 2-methylnaphthalene, benzene, toluene and tetrahydrofurane (THF). Smaller biomass sizes were favorable for higher bio-oil yields.
Effects of the Heat Carrier’s Temperature and Particle Size on the Pyrolysis of Imperata cylindrica in a Transported Bed Reactor
Authors: Kamaroddin Mohd Fadhzir Ahmad , Tuan Abdullah Tuan Amran , Mat Ramli , Amin Nor Aishah Saidina
Published: September 2014

The pyrolysis of Imperata Cylindrica in a transported bed reactor has been carried out using sand as heat carrier. This study is to determine the significant effect of the pyrolysis process condition for heat carrier temperature and particle size on the liquid yield and bio oil properties. Physical and chemical properties of bio-oil such as the water content, pH, viscosity and density were determined. The results showed that the heat carrier’s temperature highly affected the liquid product, yielding 2.30 to 11.89 wt.% in increasing the temperature from 450 to 600°C. The yield increased with larger particle size with 0.375 mm diameter gives maximum yield of 11.88 wt.% (600°C) but decreased gradually until 0.650 mm diameter afterwards.
Fast Pyrolysis of Oil Palm Kernel Shell in a Fluidized Bed Reactor: The Effect of Pyrolysis Temperature on the Yields of Pyrolysis Products
Authors: Norizan Ali , Uemura Yoshimitsu , Afif Hafizah Ahmad , Osman Noridah , Omar Wissam N. , Abdullah Bawadi , Tsutsui Toshio
Published: September 2014

This study investigates the effect of pyrolysis temperature on the yields of char, organic compounds, water and gas. Fast pyrolysis was carried out in a fluidized bed reactor of 108 mm in internal diameter operated at 400, 450, 500 and 550 °C with nitrogen gas with flow rate of 25 L(NTP)/min. In specific the effect of temperature on the yields of known and unknown organics in bio-oil is discussed. For higher total organics, 500 oC was favorable. But higher phenol and acetic acid yields, 450 oC was preferable. The major organics include acetic acid, phenol and furfural. The minor ones include 2-methylphenol, 4-methylphenol, 4-methylnaphthalene, benzene, toluene and THF.
Studies on Pyrolysis of Rice Husk Using Taguchi's L9 Orthogonal Array
Authors: Dang Khanh Vi , Yusup Suzana , Uemura Yoshimitsu
Published: September 2014

Conversion and yield of liquid product using semi-batch reactor are investigated. Selected reaction parameters were optimized, using Taguchi L9 Orthogonal Array method for the design of experiments, to yield the highest liquid product. The investigated parameters include nitrogen flow rate, sample particle size, temperature and heating rate. The effects and significance of each parameter was studied and verified through repetitive experiments. Optimum conditions for the reaction were established. Optimum conditions for pyrolysis process were at 100 ml/min of nitrogen flow rate, temperature at 500 oC, 20 oC/min of heating rate and 250μm - 500μm of particle size with liquid yield of 35.48wt%.
Interfacial Defects on Mixed Matrix Membranes and Mitigation Techniques for Gas Separation: A Review
Authors: Shimekit Biruh , Mohd Shariff Azmi , Mukhtar Hilmi , Bustam Mohamad Azmi , Elkhalifah Ali E.I. , Ullah Sami , Riaz Nadia
Published: September 2014

Development of novel mixed matrix membranes (MMMs) has become frontier candidates for improving the upper bound trade-off curve between permeability and selectivity of gases for industrial polymeric membranes. However, fabrication of ideal MMMs is practically challenging as the dispersion of inorganic phase into the polymer may produce polymeric-inorganic interfacial defects at the vicinity of the polymer matrix. For instance, the inorganic phase may cause interfacial void, polymer chain rigidification or partial pore blockage on the overall MMMs. Since there are only few studies that specifically focus on the issues of the interfacial morphology of MMMs, therefore, the present study provides brief description of the aforementioned interfacial (non-ideal) defects of MMMs and summarizes the techniques used to repair the interfacial defects for enhanced gas separation in MMMs.
Characterization and Assessment of Cockle Shell as Potential CO2 Adsorbents
Authors: Azmi Nurulhuda , Yusup Suzana , Sabil Khalik M.
Published: September 2014

Material characterization is a crucial step to ensure the characteristics and properties of the samples are comparable to the standard adsorbent and suitable for CO2 adsorption. The objective of this work is to characterize natural calcium based materials for CO2 adsorption which are obtained from waste cockle shells. Characterization analyses are conducted by using XRD, BET and FESEM. Material characterization indicates that raw cockle shell is made up of aragonite and needle-like structure. It is also shown that CaCO3 can be decomposed to CaO through high temperature calcination process. Through physisorption analysis, the samples are classified as mesoporous materials and it is shown that calcined cockle shell is better than raw cockle shell in term of surface area and pore volume. The results proved that calcium based materials could be successfully employed as sorbent for CO2 separation.
Raman Spectroscopic Study for the Determination of Monoethanolamine Concentration
Authors: Wong Mee Kee , Bustam Mohd Azmi , Azmi Mohd Shariff
Published: September 2014

Thermodynamic model is one of the important elements in designing and operating CO2 removal systems, thus accurate determination of the thermodynamic properties of CO2 in aqueous amine is of major interest for both technical and economical considerations. Quantitative Raman study of aqueous monoethanolamine (MEA) solutions of concentration ranging from 0 to 99 mass % in the spectral region between 300 and 3100 cm− 1 was performed. Band envelopes were resolved with Gaussian Lorentzian function. Progressive growth of area under these peaks with increasing concentration was used as the parameter to construct calibration curve. Area ratio of selected peaks was plotted against MEA concentration to depict the relationship between MEA concentration and each area ratio. Correlation for A1460/A933 has coefficient of determination closest to unity and lowest mean squared area. MEA concentration can be calculated from the equation derived from correlation between A1460/A933 and MEA mass %.
Influence of Orifice Shape on Reaction Rate by Hydrodynamic Cavitation
Authors: Yasuda Keiji , Kaji Toa , Xu Zheng
Published: September 2014

Hydrodynamic cavitation is expected to apply to the decomposition of chemicals and the disinfection in wastewater. In this study, the effects of upstream pressure, hole diameter and shape of orifice plate on the reaction rate of I3- formation were investigated. The reaction rate increases with increasing upstream pressure of orifice plate. The reaction rates have maximum values, when hole diameters of orifice plate are 2.7 mm at the upstream pressure of 0.9 MPa gauge and 3.0 mm at 0.7 MPa gauge. The reaction rate increases in the order of triangle < square < hexagon < circle shaped hole of orifice plate at the same hole area.
An Evaluation of Fish Scales as Potential Adsorbents: pH and Concentration Effect
Authors: Abdullah Bawadi , Vo Dai Viet N.
Published: September 2014

Experimental investigations on removal of lead contamination from polluted water by adsorption technique using local fish scales i.e.Tilapia and Merah (Oreochromos and Lutjanus). The fish scales adsorbent equilibrated nearly approaching 100% of Pb uptake over the range of concentrations and pH studied. Unexpectedly, the performance of fish scales as an adsorbent is better as compared to commercially available activated carbon.
Thermodynamic Analysis of Autothermal Reforming of Oxygenated Hydrocarbons at Thermoneutral Condition for Hydrogen Production
Authors: Azizan Mohammad Tazli , Hellgardt Klaus , Chadwick David
Published: September 2014

The thermodynamic analysis of autothermal reforming of homologue series consisted of ethanol, ethylene glycol, propylene glycol and glycerol representing oxygenated hydrocarbons were studied. The main investigation was to compare the effect of thermoneutral condition where no external air/oxygen supplied for the reaction to sustain and controlled amount of air/oxygen supplied. It was found that the higher number of oxygen atoms in these homologues molecule, the higher tendency of the reaction to be sustained at the desired temperature, and thus it only requires lesser amount of air for heating. The hydrogen selectivity however depends on the ratio of hydrogen atoms with respect to the oxygen atoms in each molecule. The presence of air however, though providing extra heating to the reactor, is offset by a lower hydrogen production.
Delignification of Empty Fruit Bunch (EFB) Using Low Transition Temperature Mixtures (LTTMs): A Review
Authors: Loong Yiin Chung , Yusup Suzana , Uemura Yoshimitsu
Published: September 2014

Biomass processing using low transition temperature mixtures (LTTMs) has the potential to become a sustainable alternative resource for production of raw materials and fuels with a neutral carbon dioxide balance. The state of art for customizing the physicochemical behaviour of these new green solvents by a prudent selection of the constituents’ nature and ratio through microwave irradiation is presented in this work. The impact of the following parameters, namely type of malic acid, molar ratio of malic acid to natural salt, water content and temperature of treatment are related to the solvation behaviour of LTTMs. An overview of the conditions for the highest efficiency in the delignification of empty fruit bunch (EFB) are described.
Study the Release of Urea from Agrium® Coated Urea Using UV-Vis Spectrometer
Authors: Trinh Thanh H. , Dao Quyen Nhat , Ku Shaari Ku Zilati , Ismail Lukman , Shuib Anis
Published: September 2014

Elucidating the release pattern of controlled release fertilizer (CRF) is important not just for manufactures but also for farmers because it assists them in making judgments of fertilizer effectiveness and nutrient planning. Investigation on the release pattern of different types of CRF both in the laboratory and in the crop-field is crucial in order to determine the effectiveness of fertilizer on plant growth. Consequently, the fertilizer application could be planned to meet the crop requirement. This paper presents a practical approach to analyze the release pattern using Agrium® coated urea. UV-Vis spectrometer is employed to analyze the amount of nitrogen released. The approach reduced analytical error by preventing sample dilution before measuring. According to laboratory results, UV-Vis spectrometer has shown a good potential to be used in studying the nutrient release behavior from CRF. A sigmoidal shape has been obtained from the release profile, and is corresponded with findings in other studies. The results satisfy the criteria for CRF specified by European Committee for Standardization. Collectively, this study demonstrated that the UV-Vis spectrometer is a promising equipment, which can be utilized in studying controlled release behavior.
Curing Characteristics and Tensile Properties of White Fly Ash Filled Natural Rubber Compounds
Authors: Mokhtar Hisyam , Nordin Razif , Shamsuddin Saidatulakmar , Noriman N.Z.
Published: September 2014

The effect of white fly ash (WFA) on cure characteristics and tensile properties of natural rubber compounds were investigated in the range of 0 to 30 phr. The size of WFA that is used in this study was 45-75 μm. Based on the result, it is found that the scorch time and cure time decreased with increasing of WFA loading. The tensile strength gradually increased to the maximum at 5 phr WFA. The further increase of WFA loading led to the decrease in tensile strength. Tensile properties such as M100 (stress at 100 % elongation) was gradually increased with the increasing of WFA loading, meanwhile, the elongation break showed a decreasing trend.
Optimization of Ethanol Production from Mango Peels Using Response Surface Methodology
Authors: Abdul Ghani Muhammad Ridzuan , Ching Oh Pei
Published: September 2014

This study aims to optimize bioethanol production from mango peels using Response Surface Methodology (RSM). The effect of temperature (25–40oC), yeast concentration (6–14 g/ml) and fermentation time (48–96 hours) on bioethanol yield was investigated. Prior to the fermentation process, mango peels were treated with 0.25–1% (w/v) sulphuric acid. Optimum glucose yield was obtained at 0.25% (w/v) sulphuric acid. RSM using 3-factor 2-level central composite design (CCD) was employed to evaluate and optimize the synthesis parameters. Based on numerical optimization, the optimum fermentation conditions were at 38oC using 6 g/ml yeast for 48 hours, giving a yield of 7.34 g/ml bioethanol.
Biomethane Production and Palm Oil Mill Effluent Treatment by Co-Cultivation of Nannochloropsis oculata
Authors: Ahmad Ashfaq , Shah Syed Muhammad Usman , Othman Mohd Fariduddin , Abdullah Mohd Azmuddin
Published: September 2014

Co-cultivation of Nannochloropsis oculata with Oil Palm Empty Fruit Bunches (OPEFB) was explored for biomethane production and POME treatment. The experimental results were analyzed and modeled using a multilevel factorial design (MFD) of response surface methodology (RSM). Maximum specific biogas production rate (0.126 m3 kg-1 COD day-1) and biomethane production (4813.0 mL CH4 L-1 POME day-1) were achieved with 2 mL mL-1 POME of microalgae and OPEFB 0.12 g mL-1 POME. POME treatment after 3 and 7 days with microalgae achieved higher removal efficiency (56-98%) of COD, BOD and TOC, than without microalgae.
Determination of Antioxidant Activities and Total Phenolic Contents of Three Cyanobacterial Species
Authors: Ali Hamdy Elsayed Ahmed , Shanab Sanaa Mahmoud Metwally , Abo-State Mervat  Aly Mohamed , Shalaby Emad Ahmed Ahmed , El Demerdash Usama Mohamed Nour , Abdullah Mohd Azmuddin
Published: September 2014

The antioxidant activity and total phenolic content of different extracts (hexane, chloroform, ethyl acetate, ethanol (70%) and water) of three tested cyanobacterial species (Phormidium sp., Oscillatoria sp. and Nostoc muscorum ) were evaluated, using 2,2 ́-diphenyl-1-picrylhydrazyl (DPPH) scavenging method and Folin–Ciocalteu method, respectively. The ethanolic extract of Oscillatoria sp. possessed the highest antioxidant activity (69.13±0.35 %) and therefore could be potential source of natural antioxidants. The correlation coefficients between the antioxidant activities and the phenolic contents were very small in most of extracts (R2 = 0.0291-0.2934). However, the water extract demonstrated relatively higher value (R2= 0.7446). Thus, phenolic compounds may not be considered the major contributors for the antioxidant activities of these cyanobacterial species. So, other antioxidant substances may be present in the extract and share in this activity.
Mechanical Pretreatment of Lignocellulosic Biomass for Biofuel Production
Authors: Che Kamarludin Siti Norsyarahah , Jainal Muhammad Syafiq , Azizan Amizon , Safaai Nor Sharliza Mohd , Mohamad Daud Ahmad Rafizan
Published: September 2014

Lignocellulosic biomass (LB) sources which are readily available in abundance are widely considered as a potential future sustainable raw materials for biofuel production. Typically, biofuel production involved several chemical and mechanical steps consisting of pretreatment, hydrolysis, fermentation and separation. The pretreatment step is considered as one of the most vital part of the whole processing scheme due to the impact it had on the efficiency of the subsequent processing steps. In this study we reviewed the mechanical pretreatment of LB focusing mainly on the size reduction technique by grinding process. Grinding is one of the proven preliminary pretreatment techniques employed in biomass conversion to liquid biofuel. However, this technique is known to be costly due to high energy consumption. In view of this, an efficient and cost effective pretreatment technology is required in order for the biofuel to be produced at a competitive level. At the same time, the impact on environment caused by the conventional pretreatment processes can be minimized. Thus, a new combined chemical-mechanical pretreatment is considered whereby a green ionic liquid (IL) solvent is introduced.
Bio-Oil Production under Sub- and Supercritical Hydrothermal Liquefaction of Oil Palm Empty Fruit Bunch and Kernel Shell
Authors: Chan Yi Herng , Yusup Suzana , Quitain Armando T. , Uemura Yoshimitsu
Published: September 2014

Two types of Malaysian oil palm biomass; namely Empty Fruit Bunch (EFB) and Palm Kernel Shell (PKS) are liquefied using sub-and supercritical water to produce bio-oil. Effects of temperatures (360, 390 and 450 °C) and pressures (25, 30 and 35 MPa) of the liquefaction of biomass on the bio-oil yields are investigated. The optimum liquefaction conditions for EFB and PKS using water are at supercritical conditions. PKS which consists of higher lignin content yields maximum bio-oil of about 41.3 wt % at temperature of 450 °C and the bio-oil yield from EFB is about 37.4 wt % at temperature of 390 °C.
Heavy Metal Removal by Oil Palm Empty Fruit Bunches (OPEFB) Biosorbent
Authors: Daneshfozoun Safoura , Abdullah Bawadi , Abdullah Mohd Azmuddin
Published: September 2014

This study developed an effective and economical physical pretreatment of OPEFB to be used as biosorbent for the removal of heavy metal ions such as Cu+2, Zn+2 and Pb2+. The effects of fibres sizes, metal ions concentration (100-1000 ppm), initial pH (4-10) and contact time (20-150 min) were investigated in batch system. Samples were characterized with Atomic Absorption Spectrometry (AAS), Transmission Electron Microscopy (TEM) and Fourier Transmission Infra-red Spectroscopy (FTIR). Results showed pH-dependence adsorption efficiency and increased adsorption with initial metal concentrations where more than 92% adsorption efficiency achieved. We have successfully developed an eco-friendly, low cost adsorbent without any chemical modification or excessive energy disposal.
Modifying the Refractive Index of Epoxy Resins Using Reactive Diluents to Enable Optical Self-Sensing in E-Glass Fibre Composites
Authors: Rauf Abdul , Hand R.J. , Hayes S.A.
Published: September 2014

Optical self-sensing employs the reinforcing fibres as self-sensing elements thus eliminating the need for additional sensing elements in smart materials. At present optical self-sensing systems employ expensive optical adhesives to lower the refractive index of the matrix as the refractive index of the cladding material must be lower than the light-guiding glass fibres. In this study the refractive index of an aerospace certified, commercial laminating resin (Araldite LY5052/Aradur HY5052) was reduced with propylene carbonate, (a commercial reactive diluent). This modified resin with lower refractive index facilitated light transmission through impregnated E-glass reinforcing fibres used as optical self-sensing elements in composites. The effects of propylene carbonate addition on the mechanical properties of the epoxy were also analysed and presented here.
Effect of Nanofillers on the Spreading Behavior of Biopolymer Materials on Urea Surface
Authors: Samsudin Yon Norasyikin , Zulkefely Nurul Izzaty Faizzen , Izhar Sohibatul Muizzah Mohamad , Ku Shaari Ku Zilati
Published: September 2014

This paper presented new approach where a new modified biopolymer reinforced with bentonite nanoclay is developed and used as the coating material for controlled-release fertilizer. Good wettability properties between coating material and urea surface is necessary to provide uniformity during the coating process of controlled release fertilizer. Seven different blending ratio of modified biopolymer solutions are prepared and evaluated for their wettability properties. The wettability properties measured include the surface tension, contact angle and maximum spreading diameter. Optical Contact Angle device comes with a Charged-Coupled Device (CCD) camera was used to capture every single image of the droplet impact behavior. From the analysis, it is proven that with addition of 2% nanoclay filler reinforced into modified biopolymer with blending ratio of 50/15/2.5/7.5 has the best wettability properties and provides better spreading behavior.
Effects of Intercalated Mono-, Di- and Triethanolammonium Cations on the Structural and Surface Characteristics of Sodium Form of Bentonite
Authors: Elkhalifah Ali E.I. , Bustam Mohammad Azmi , Mohd Shariff Azmi , Ullah Sami , Shimekit Biruh , Riaz Nadia
Published: September 2014

The present study investigates the effects of intercalation process of protonated primary, secondary and tertiary amines on structural and surface characteristics of sodium form of bentonite clay. For this purpose, sodium form of bentonite clay was prepared and then exchanged with mono-, di-and triethanolammonium cations via intercalation mechanism into the interlayer space of the clay. The prepared samples were characterized by XRD and BET techniques. An increase in the d-spacing of bentonite clay with the molar mass of amines was observed in their x-ray diffractograms, following the order of: triethanolamine > diethanolamine > monoethanolamine. The BET results showed a gradual decrease in the BET surface area with the increase in the molar mass of amines used. Based on the results obtained, it can be concluded that the molar mass of amines has significant effects on structural and surface properties of bentonite clay.
Thermal and Morphological Properties of Chitosan Filled Epoxy
Authors: Satheesh Britto , Tshai Kim Yeow , Warrior Nick
Published: September 2014

This paper investigates the effects of polysaccharide additive agent on the morphological and thermal properties of thermosetting polymer. The weight percentage (wt%) of Diglycidyl Ether of Bisphenol A (DGEBA) epoxy resin to Hexamethylenediamine (HMDA) hardener were kept constant while a varying wt% of chitosan, ranging from 0 to 10 wt% was introduced. The chitosan filled epoxy hardener mixture was allowed to cure at 40°C for a period of 12 hours. Dynamic Scanning Calorimetry (DSC) and Thermal Gravimetric Analysis (TGA) were conducted on the specimens to analyse the effects of chitosan loading on thermal stability and transition temperature while Atomic Force Microscopy (AFM) was used to investigate the changes to its morphological property. At chitosan loading of 2.5 wt% and below, good dispersion of the additive was observed. Apparent agglomeration and phase separation were formed when chitosan content increases above 7.5 wt%. The formation of bulky chitosan agglomeration was found capable of enhancing the thermal stability of the thermoset polymer. The diamine acted as the co-reactants with DGEBA as well as spacer which decrease the effect of material brittleness due to addition of chitosan.
Optimum Excess Air for the Utilization of Palm Biodiesel Blends in Fire Tube Boiler
Authors: Rachman Susila Arita , Komariah Leily Nurul
Published: September 2014

Biodiesel has great potential to be applied in a variety of combustion engines, such as boiler. The excess air control in the combustion process plays an important role to produce an ideal combustion performance. The changes in the physical properties of the fuel due to the use of palm biodiesel or its blends affect the amount of required air to the combustion chamber. This study was conducted in a package type fire tube boiler with a design pressure of 3 bars and heat capacity of 60,000 kCal/hour. Palm biodiesel blends were set as boiler fuel with composition of 10%, 20%, 30% and 50% in diesel oil. Fan damper scale is part of the burner system that in charge to regulate the air flow into the combustion chamber. The fan damper scale was set in the range of 4.0-4.9. For higher blends of biodiesel, the fan damper was optimum in lower scale (4.0 or less). More biodiesel in blends, less combustion air was needed to enter. Hence, the excess air of palm biodiesel combustion in fire tube boiler was in range of 57-67%.
Approximate Analytical Method to Stefan Problem for Spheres with Wide Temperature Range of Phase Transition
Authors: Chiba Ryoichi
Published: September 2014

The two-dimensional differential transform method is applied to solve the one-dimensional phase change problem for a solid sphere with time-dependent boundary temperature. The problem assumes that the phase change occurs over a range of temperatures and the initial temperature of the sphere is an arbitrary constant. An approximate analytical (series) solution is derived for the temperature profile in the melting or solidifying sphere. The solution is based on the apparent specific heat method. Numerical results illustrate the effects of the Stefan number, which is the ratio of sensible heat to latent heat, on the transient temperature profile in the sphere.
The Design of Used Temperature Measurement Circuit
Authors: Lei Qi , Yan Zhang , Feng Wen , Zong Yao
Published: September 2014

Platinum resistance sensor has the characteristics of large measuring temperature range, high accuracy and stable performance. It is an ideal temperature detecting element, and it is applied widely in industry. This paper designs two kinds of temperature measurement circuits, and expounds the working elements of each kinds of project. We contrast two projects though the follow two factors: the convenience of range regulation and linearization. We choose the better projects. They are provided with applied simply, high precision and low cost.
Analysis of Mechanical Error’s Effect on the Measurement Accuracy of the Six-Axis Force Sensor
Authors: Liang Ru Nan
Published: September 2014

Force sensor based on the six degree of freedom (6-DoF) Stewart platform is universal for wide applications. Mechanism errors are significant for its measuring accuracy. However, because of the multi-variables and the complicated forms, it is difficult to solve the expression directly. The Monte Carlo method is proposed based on the analysis of the system structure and the mathematical model. The effect of mechanism errors on the measurement accuracy was assessed. With this method, a complex accuracy expression of the sensor could be avoided. It also provided a theoretical basis for designing the sensor of the Stewart platform.
Damage Observation of Glass Fiber/Epoxy Composites Using Thermography and Supported by Acoustic Emission
Authors: Bale Jefri , Valot Emmanuel , Monin Martine , Laloue Peggy , Polit Olivier , Bathias Claude , Soemardi Tresna Priyana
Published: September 2014

This work presents an experimental study to monitor the damage propagation of composite material by non destructive testing (NDT) method. In order to achieve this, an open hole condition of glass fiber/epoxy composite has been used as the specimen test under static tensile loading and observed using two different real-time monitoring techniques of NDT namely infra-red (IR) camera and supported by Acoustic Emission. The results show that the thermal response and acoustic emission signals give a good detection on damage appearance and damage propagation of glass fiber/epoxy composite under static tensile loading conditions.
Measurements of Surface Roughness in Ultrasonic Assisted Grinding of Ceramic Materials
Authors: Wdowik Roman , Magdziak Marek , Porzycki Janusz
Published: September 2014

The paper presents the results of investigations regarding surface roughness measurements in ultrasonic assisted grinding of selected ZrO2 based ceramic material. There are different results, in the area of surface roughness measurements, presented in the literature. The entry data of hybrid machining process (e.g. grinding wheel type, feed, machining strategy or process variant) may influence these results. The analysis of literature encourages to take up the investigations of surface quality in ultrasonic assisted machining. These investigations may be performed for specific ceramic products and technological tasks which are commonly applied in ceramic machining processes. The knowledge about the machining of ceramic materials in different sintering states is very limited. Based on this finding, ultrasonic assisted and conventional machining processes of ZrO2 based ceramic material in different sintering states were investigated.
Characteristic Analysis on Transverse Comb Structure Using PSpice
Authors: Kavitha C. , Ganesh Madhan M.
Published: September 2014

An analysis of transverse comb structure based MEMS accelerometer is carried out. Its static and dynamic behavior is analyzed by employing a simple electrical equivalent circuit in the acceleration range of 0-30g. The device is simulated for dc, transient and frequency conditions. In the transient analysis, the device is excited with sinusoidal and step input acceleration and the proof mass displacement is evaluated. It is found that, the capacitance and displacement values obtained from our simulation matches well with reports from ANSYS Workbench®. The maximum displacement in the structure is evaluated at different condition and the effect of damping is investigated.
Single Beacon Indoor Localization System Based on Counter-Synchronized Compass and RSSI
Authors: Eu Kok Seng , Yap Kian Meng , Tee Tiam Hee
Published: September 2014

Indoor localization system has been a popular research area in recent decades and many of them are based on multiple beacons localization method. However, there are some special applications to which the multiple beacons method is not an optimal solution due to its overdesign and cost of redundancy. Multiple beacons method uses at least three transducers and each transducer’s location must be known to find the location of a target object by using either Triangulation or Trilateration calculation. When the multiple beacons method is applied in an items lost and found system, the precise Cartesian coordinates of a target item can be found, but it is definitely overdesign and incurring redundant cost. It is due to the fact that the target item requires only two simple information i.e. Clock orientation and distance information; therefore, single beacon is enough for the task. In this paper, we propose a single beacon localization method to optimize the solution in the items lost and found system by utilizing clock orientation and estimated distance information. The proposed single beacon localization algorithm has been demonstrated and proven that it can be one of the optimal solutions for items lost and found system.
The Effects of Laminate Orientation in Resin Infused Kenaf Fibre Reinforced Epoxy Composite
Authors: Tshai Kim Yeow , Wong Kok Cheong , Tan W.J. , Chai A.B.
Published: September 2014

Water retted kenaf fibre reinforced epoxy laminates with five distinct fibre orientations, unidirectional, [+30/0/-30], [+45/0/-45], [+60/0/-60] and [90/] s were produced through resin infusion technique. The fibre weight fraction in each laminate was controlled and the effects of varying orientation in the resulting composite lamina were characterized through tensile and impact properties of the specimens. Superior tensile strength and modulus were observed for the unidirectional lamina while the orthogonal lamina [90/] s depicted the greatest resistance to impact. Specimen with higher proportion of fibres aligned parallel to the loading direction show greater enhancement in tensile strength while impact property of the lamina was found to be greater with increases in fibre orientation perpendicular to the direction of impact load.
Deflection Analysis of Ionic Polymer Metal Composites (IPMC) Actuators for Bionic Joints
Authors: Farid Muhammad , Gang Zhao , Khuong Tran Linh , Sun Zhuang Zhi , Rizwan Muhammad
Published: September 2014

Ionic Polymer Composite Material (IPMC) is a flexible material and has concealed many benefits to inspire the scientists and researchers to explore its physiognomies for real-world applications in various fields. Currently, the research area of IPMC can be alienated into two branches. One deals with the upgrading of the material properties to make it further advantageous and dependable while the other encompasses the consideration of new application capacities. In this paper, a new application of IPMC is recommended to stimulate a rigid link that can imitate a bionic knee joint for a grass hopper. Secondly, force-deflection mathematical model has been developed for the proposed design to investigate the amount of deflection that can be achieved by a certain force provided by the IPMC material strips. In this paper, the model is derived for the upward movement of the link; however the same model can be applied to the reverse direction because of the unanimity of the material properties and specifications.
High-Temperature Degradation of Mortar Containing Rubber Aggregates and EVA Binder Evaluated by Impact-Echo Method
Authors: Štefková Daniela , Tupý Michael , Sotiriadis Konstantinos , Šamárková Kristýna , Chobola Zdeněk
Published: September 2014

The application of Impact-echo acoustic method to evaluate the degradation and the composition of mortar composites modified with rubber aggregates and EVA polymer binder degraded at high temperatures was studied. Specimens were prepared by using a type CEM I Portland cement and siliceous sand, as well as by substituting 25% of sand with shredded automobile tires and by adding of EVA polymer binder (10% w/w to cement mass). The samples were subjected to high-temperature treatment in the temperature range of 200-400 °C. The results of non-destructive testing of such samples by acoustic methods confirmed the differences in the structure of mortar specimens. Addition of rubber aggregates in samples caused absorption of lower frequency as compared to reference specimens. A significant decrease of the absorbed frequencies was observed depending on the temperature. The largest decrease happened after exposure of samples at 200-300 °C. It indicates that the effect of heat treatment was reduced when the EVA binder was added.
Defective Reduction in an In-House Recycle Process of Hard Disk Drive Media
Authors: Damrongseree Keeratipan , Tharmmaphornphilas Wipawee
Published: September 2014

This paper aims to reduce defectives in an in-house recycle process of hard disk drive media. The Six Sigma approach is applied to find out the factors which affect the sunray defect statistically and to obtain the optimal setting of each factor. Currently, defective rate is 23% and a sunray defect on media is identified as a major problem with 9.64% defective rate. It is found that a minimal defective rate of sunray defect is achieved with the setting of the load of rubber pusher at 106.5 gram, the spindle speed during tape move up at 2,500 rpm and the traverse speed of tape at 70 cm/min. Finally, the process with the optimal machine settings is implemented along with applying work instruction and training. It can reduce the defective rate from 9.64% to 3.2%.