bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of Microstructure and Mechanical Properties of Resistance Spot Welded Dissimilar Joints Between Ferritic Stainless Steel and Weathering Steel
Authors: Subrammanian A , Jabaraj D.B. , Bupesh Raja V.K.
Published: June 2015

Resistance spot welding is widely used in automobile and rail car manufacturing industries. In this research work, resistance spot welded dissimilar joints of ferritic stainless steel and weathering steel sheets is investigated for mechanical and metallurgical properties. Ferritic stainless steel AISI 409M and weathering steel corten A (ASTM A 242) of 2mm thickness were used in this work. Spot welding was done at different current values, keeping other parameters such as electrode force, electrode tip diameter and weld time as constant. Test specimens were subjected to tensile shear test and micro hardness test to assess the mechanical properties of the weld joints. The influence of welding current on nugget growth, fusion zone hardness, peak load, and failure energy and failure mode during tensile shear test, was investigated at various current ratings. The results showed that, with increasing value of current, peak load increased correspondingly. Nugget shape was found to be near symmetrical. Nugget diameter was found to be increasing with increase in current, in expulsion free welds. Interfacial mode of failure was noticed at low current values, whereas, at higher current values, pull out mode of failure was observed. Presence of martensite was observed in the fusion zone. Micro hardness values at fusion zone were found to be more than that of both heat affected zones and base metals.
Comparative Vibration Analysis of Multilayered Filament Wound Composite Cylinders with Various End Conditions
Authors: Elphej Churchill S.J. , Prakash S.
Published: June 2015

This work includes design, fabrication and comparative vibration analysis of multi-layered filament wound composite cylinders of S-Glass epoxy and Basalt epoxy of 500mm length, 100mm diameter and 3mm thickness. The Vibration analyses were done separately on both the cylinders for various end conditions viz., free-free, fixed-free, and fixed-fixed. The natural frequencies of two materials are compared experimentally. Natural frequencies varies with end conditions, material properties, proportions of constituent materials present in the composites, geometrical parameters etc.The natural frequencies of all such parameters were determined using experimental setup which consists of a exciter, accelerometer and DAQ (DEWESOFT 7.0.5 software).
Modeling of Delamination in Drilling of Particleboard (PB) Composite Panels
Authors: Valarmathi T.N.
Published: June 2015

Wood composite panels are widely used in construction and furniture industries. They are very much preferred in interior and exterior decoration, house hold products and toys, etc. because of the aesthetic appearance and their high-quality properties. In manufacturing of wood composite products various machining process are used. In final assembly of various parts of a end product, drilling is the most commonly used machining operation. The cutting forces developed during drilling process having more effect on the surface quality of the drilled holes. Hence the drilling damages like delamination must be controlled to ensure the surface quality of the final product. In controlling these forces the contribution of input drilling parameters is more. The objective of this work is to study the influence of input control parameters to obtain the optimal cutting conditions. In the present study the drilling experiments are performed using Taguchi design of experiments with Taguchi L27 orthogonal array on particleboard (PB) composite panels using high speed steel (HSS) twist drills with three different drill diameters. Response surface methodology (RSM) is used to develop a mathematical model to predict the influence of input control parameters on delamination. The adequacy of the model is checked using Analysis of variance. It is revealed that high spindle speed with low feed rate and smaller drill diameter combination gives better results.
Modeling of Surface Roughness in Drilling of MDF Panels
Authors: Valarmathi T.N. , Palanikumar K. , Sekar S.
Published: June 2015

Medium density fiberboard wood composite panels are preferred for many domestic and industrial applications over the natural wood because of their high-quality properties. The aesthetic appearance of wood composites makes them suitable for interior and exterior construction works. Among various machining process, drilling is the most frequently used machining operation in the furniture industry in assembly of panel products. During drilling process the drill exhibits cutting forces such as thrust force and torque. The surface quality of the drilled holes are mainly affected by the cutting forces developed during drilling process which causes surface roughness, delamination like damages which leads to the rejection of the final product. Hence the reduction of the drilling defects, the control of the cutting forces is very much essential. The drilling parameters play an important role in controlling the cutting forces. The objective of this work is to study the influence of input control parameters such as spindle speed, feed rate and point angle on surface roughness in drilling of MDF panels to obtain the optimal cutting conditions. In the present study the drilling experiments are conducted using Taguchi design of experiments on wood composite panels with high speed steel (HSS) twist drills with different point angles on vertical machining center using at dry condition. Three levels and three factors are considered. Taguchi L27 orthogonal array is used. Response surface methodology is used to develop a mathematical model to predict the influence of input control parameters on cutting forces. Analysis of variance is used to check the adequacy of the model. Surface roughness is increased with an increase of feed rate and drill point angle and decreased with an increase in the spindle speed. It is revealed that high spindle speed with low feed rate and smaller point angle combination gives better results in drilling of wood composite panels.
Roughness Analysis of the Holes Drilled on Al / SiC Metal Matrix Composites Using Atomic Force Microscope
Authors: Senthilbabu S. , Vinayagam B.K. , Arunraj J.
Published: June 2015

Metal matrix composites (MMCs) possess significantly improved properties including high strength to wear ratio, high modulus, superior wear resistance and corrosion resistance compared to unreinforced alloys. In spite of the advantages, the Aluminium based metal matrix composites have not yet found a wide employment in the commercial applications, because the the matrix cause serious problems in machining / drilling, such as high drilling forces, tool wear, and poor surface finish due to the hard particles. The drilling of Al/SiC metal matrix composite has received a serious attention for many years. Different specimens were prepared from Aluminium / Silicon carbide (Sic) metal matrix composites by stir casting method by varying the weight percentage of Sic and the investigation has been carried out on the specimen by drilling holes on them. Surface finish is an important factor to be taken into account in the drilling process. So, it is more necessary to predict the average surface roughness of the materials. Then the roughness of the drilled holes made on the specimen was studied using Atomic force microscope. The investigation was carried out with their characteristics being studied by comparing various parameters such as cutting speed, feed rate and so on. The average roughness was studied on 30µm X 30µm and 15 µm X 15µm horizontal section and vertical section. Their histograms were also studied.
Evaluation of the Double Shear and Hardness of Abaca and Flax Reinforced Polymer Composite for Automotive Applications
Authors: Manickavasagam V.M. , Vijaya Ramnath B. , Elanchezhian C. , Sundarrajan R. , Vickneshwaran S. , Santhosh Shankar A. , Kaosik R. , Santhosh Kumar K.
Published: June 2015

Advancement in Science and technology over the past decade has made the human society to venture into using hybrid materials for variety of applications. Natural fiber composite materials are one among those new emerging engineering materials. These materials are finding increased usage due to their low cost and eco-friendly nature. This paper deals with the fabrication and characterization of abaca, flax based hybrid composite. The properties of hybrid composites are compared to the composite containing any one of the constitutional fibers of hybrid composite. The characterisation is based on behaviour of composite under various mechanical testing. The tests include double shear strength and Hardness. The inner filament brakeage and crack propagation are studied using Scanning Electron Microscope (SEM).
EDM Process Parameters Optimization Using Taguchi Method
Authors: Sengottuvel P. , Palanisamy V. , Arun J. , Anbusagar N.R.R. , Hussain J. Hameed
Published: June 2015

In this paper , the parameters of Electrical Discharge Machine (EDM) are investigated during the machining of Inconel 718 by using different sizes of circular Aluminum electrode. Demand for better surface finishes are increasing recently for all materials, the low rigidity and high material removal rate of Inconel alloys offers a challenging task in obtaining better Surface Finish. The analysis of surface characteristics like Surface Roughness (SR) of Inconel 718 material is carried out an excellent surface finish can be obtained by setting the machining parameters at optimum level. Experimentation was carried out by using Taguchi’s L9 orthogonal array under different conditions of parameters. The response of SR is considered for improving the machining efficiency. Optimal combination of parameters was obtained Taguchi Optimization technique. The confirmation experiments results shows that the significant improvement in Surface Finish was obtained. ANOVA have been used to analyze the contribution of individual parameters on Surface Roughness. The experimental result demonstrates that the Taguchi method satisfies the practical requirements.
Modeling and Optimization of WEDM of Titanium
Authors: Nandakumar C. , Mohan B. , Senthilkumar C. , Vickram K.
Published: June 2015

Wire-electro discharge machining (WEDM) is one of the important non-traditional machining processes used to machine difficult-to-machine materials and complicated profiles. Being a high degree of complexity process, it is unfavourable to determine optimal parameters for improving cutting performance. Metal removal rate and surface finish are most important response parameters, which decide the performance on cutting. The single optimal combination of cutting parameters is not there, as their influences on the metal removal rate and the surface finish are quite the opposite. In the present study, a multiple regression model is used to represent relationship between input and output variables and the parameters were optimized based on response surface metho dology (RSM).
Optimisation of Shutter Speed in Machine Vision Technique for Monitoring Grinding Wheel Loading
Authors: Ragavanantham S. , Kumar S. Sampath , Shyam M.S.
Published: June 2015

Grinding is an abrasive machining process which controls the surface finish of the materials in production of industrial components at the end stage. During the grinding process, wheel gets loaded with swarf and this loading will affect the cutting ability of the wheel and also the surface finish of the job. Hence the grinding wheel is to be dressed at appropriate time intervals and for necessary time duration. At present, the monitoring of grinding wheel loading and dressing is done by the operator i.e., the frequency of dressing and duration of dressing is determined by the operator based on his experience. Hence there arises a need to develop a systematic approach to this problem which can monitor the process and if not accurately should at least produce a realistic estimate of the percentage of wheel loading, frequency of dressing and duration of dressing. In machine vision system, Shutter speed is an important factor which will affect the image quality. Hence, in this work, attempts are made to monitor wheel loading using a low cost-high speed camera with variable shutter speed and the shutter speed is optimized for the better image quality.
Optimization of Impact Strength in Dissimilar Materials by Using Friction Welding Process
Authors: Shanjeevi C. , Satish Kumar S. , Jobin Thomas Joseph
Published: June 2015

Friction welding is a solid state process used mostly for joining dissimilar materials due to mass production with less time consuming. The aim of this work is to study the dissimilar joints of austenitic stainless steel and copper for evaluating the impact strength. The experiment is conducted by using Taguchi’s L9 orthogonal array for determining the value of impact strength. The input parameters such as friction pressure, upset pressure, rotational speed and burn-off length were considered and the optimum process parameter was determined based on the response of impact strength. The predicted value of impact strength was validated by conducting the confirmation run using optimum parameters. The analysis of variance (ANOVA) is conducted for the mean of impact strength.
Optimization of Linear Layout Problem in Flexible Manufacturing System Using Evolutionary Algorithms - Case Study
Authors: Saravanan M. , Ganesh Kumar S. , Srinivasa Raman V.
Published: June 2015

Linear layout is the commonly major preferred arrangement of the flexible manufacturing systems (FMS). The proposed enhanced sheep flock heredity algorithm to solving the unequal area linear layout problem through the real case study problem. The proposed model is to minimize the transportation cost with non-overlapping. Computational results show that proposed sheep flock heredity algorithm (SFHA) can obtain better than particle swarm optimization (PSO) and existing method.
Computational Intelligence in Optimization of Process Parameters in Turning Metals and Composites – A Review
Authors: V. Sivaraman , Prakash S.
Published: June 2015

In the modern competitive scenario in manufacturing industries, producing products with low cost, less time and good quality are the ultimate goal of any manufacturer. To achieve the goal, several optimization tools are developed to optimize the process parameters of the machining process. Turning is one of the machining processes that cannot be avoided in any manufacturing industries. In this review, optimization of process parameters in turning process by computational intelligence (CI) paradigms for the past ten years is studied. Optimization by CI paradigms such as Fuzzy System (FS), Evolutionary Computation techniques Genetic Algorithm (GA), Swarm Intelligence including Particle Swarm Optimization (PSO), Ant Colony Optimization (ACO), Artificial Neural Networks (ANN) etc., is considered. In turning process, surface roughness, tool wear, production time and cost are optimized.
Investigation of Particle Segregation and Solidification Time in FGM's Using Centrifuge Casting Technique
Authors: Chethan K.S. , Aithal S. Kiran , Madhusudan A. , Shailesh Rao
Published: June 2015

Functionally Graded Materials (FGM) is a newly evolved concept to get desired properties in the material wherein the intermediate layer is transient since the particle size distribution gradually changes. Centrifugal casting [1] can produce only hollow shapes and Centrifuge casting can produce solid shape FGM very effectively. The study of particle distribution in a fluid using centrifuge casting process is carried out considering sand as particle and its distribution is studied under water, for different viscosity values and for viscosity varying with respect to temperature. Based on centrifugal force and density difference, an attempt has been made to mathematically model the centrifuge casting force to estimate the particle distribution over the length of the specimen and also to assess the influence of process parameters such as rotational speed (G-force) and density of the particles.
Optimization of the Location of Secondary Sources for the Active Engine Vibration Acoustic Noise Control in the Generator Room
Authors: Ramachandran T. , Lenin Babu M.C.
Published: June 2015

The noise acoustic control in the interior of a diesel engine generator room model is studied and optimized. The finite element modelling and discretization of the engine room is carried out and the noise control is achieved using global active control of sound. The Genetic algorithm (GA) is used to find the optimized location of secondary sources to minimize the sound pressure level at receiver’s location. The secondary sources strengths for the active noise control system are computed using quadratic minimization acoustic potential energy. It is found that the sound pressure level at receiver’s location has been significantly reduced with changing the secondary source positions from arbitrarily to optimal location.
Investigation of Multi-Dimensional Cellular Manufacturing System Using Meta-Heuristic Method
Authors: Saravanan M. , Karthikeyan S. , Ganesh Kumar S.
Published: June 2015

Group technology is commonly preferred arrangement in the Cellular manufacturing system (CMS). Since worker have an important role in doing jobs on machines, assignment of worker to cells becomes a crucial factor for utilization of cellular manufacturing system. In this paper, the objective is to minimize the number of voids and exceptional element in a cell. Computational fallout demonstrate that planned particle swarm optimization (PSO) algorithm can obtain better objective function values in less computational time than existing method.
Scheduling to Minimize the Sum of Weighted Total Flow Time and Makespan in a Permutation Flow Shop with Setup Time
Authors: Saravanan M. , Vijayakumar S. Joseph Dominic , Srinivasan R. , Singarayar S. Paul
Published: June 2015

The Permutation Flow shop Scheduling Problem is a typical combinational optimization problem and has been proved to be strongly NP-hard. This paper deals with B-GRASP algorithm meta-heuristic in finding the solution and in analyzing the best the optimal schedule, thus minimizing the bi-objectives such as weighted makespan and total flow time. The proposed approach is evaluated using benchmark problems taken from Taillard and compared with simulated annealing algorithm. Computational experiments indicate that the proposed B-GRASP algorithm is a feasible and effective approach for the multiobjective problem.
Preparation of Lignopolyols by Chemical Modification of Kraft Lignin from Oil Palm Lignocellulosic Waste
Authors: Faris Abbas Hasan , Abdul Rahim Afidah , Mohamad Ibrahim Mohamad Nasir
Published: June 2015

The main objective of this research was to describe the thermal and chemical characteristics of lignopolyols. Lignin was extracted from oil palm empty fruit bunch after kraft pulping process. Oxypropylation reaction was achieved by reacting kraft lignin with propylene oxide under alkaline conditions at room temperature. The physical and chemical properties of lignopolyols were evaluated by FTIR, NMR, GPC, TGA, and DSC. Lignopolyol exhibited higher chemical activity than kraft lignin. The polyols used as precursors in biomass-based wood adhesives preparation demonstrated promising results. Keywords: kraft lignin, lignopolyol, oxypropylation, NMR spectroscopy, DSC
The Effect of LiCF3SO3 Complexed MG30-PEMA Blend Solid Polymer Electrolyte
Authors: Ayub Siti Fadzilah , Zakaria R. , Nazir K. , Aziz A.F. , Yahya Muhd Zu Azhan , Ali A.M.M.
Published: June 2015

In this work, solid polymer electrolyte compose of blended 30% poly (methyl methacrylate) grafted natural rubber (MG30)-poly (ethyl methacrylate) (PEMA) polymer blend doped with Lithium trimethasulfonate (LiCF3SO3) films were prepared by solution casting technique. . FTIR analysis showed that the interactions between lithium ions and oxygen atoms occur at the carbonyl functional group C=O where there is shifting in wavenumber from 1728 cm-1 of pure blend to lower wavenumber of blended MG30-PEMA on the MMA structure in both MG30 and PEMA. DSC analysis showed miscibility of polymer blend. From Electrochemical Impedance Spectrocopy analysis, ionic conductivity increase with the increasing of salt concentration. Maximum conductivity at room temperature is 9.20 x 10-6 Scm-1 was obtained when 30 wt% of LiCF3SO3 was added into the system. Ionic conductivity temperature dependence plots found obeys the Arrhenius rule.
Chemical Interaction, Conductivity and Thermal Properties of Kappa Carrageenan Based Polymer Electrolytes
Authors: Mobarak Nadhratun Naiim , Ghani M.A. , Abdullah M.P. , Ahmad Azizan
Published: June 2015

With the growth of green technology, the usage of biopolymer becomes important. The potential of kappa carrageenan as a host polymer consisting of different concentration of acetic acid was investigated in this study. The polymer electrolyte of kappa carrageenan was prepared by solution-casting technique. The attenuated reflection Fourier transform infrared (ATR-FTIR) spectroscopy showed there are shifting of wavenumber that represents hydroxyl, sulphate and ether stretching which confirmed the formation of polymer- acetic acid complex. The electrochemical impedance spectroscopy (EIS) showed the highest conductivity achieved was 4.48 ×10-7 S cm−1 for kappa carrageenan incorporated with 5% acetic acid at room temperature and thermo gravimetric analysis (TGA) showed that polymer electrolyte based on kappa carrageenan exhibited good thermal stability with a decomposition temperature higher than 200 °C. These indicate that kappa carrageenan display good thermal and conductivity properties which can be applied as a host polymer for solid polymer electrolyte application.
Impedance Behavior of Treated Methyl-Grafted Natural Rubber Polymer Electrolytes
Authors: Fairoz Aziz Ahmad , Nazir Khuzaimah , Ayub Siti Fadzilah , Zakaria Rosnah , Yahya Muhd Zu Azhan , Marwan Bin Ali Abdul Malik
Published: June 2015

Methyl-grafted natural rubber (MG30) was treated with N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) to enhance it anti-aging properties. The treated MG30 was used as polymer electrolyte by incorporating lithium trifluoromethane sulfonate (LiTF) through solution-cast technique. The impedance behavior of the sample has been carried out by analyzing the dielectric permittivity, dissipation factor, dielectric modulus and ionic conductivity as a function of temperature at different frequencies through impedance spectroscopy. Keywords: Methyl-grafted natural rubber, polymer electrolyte, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, ionic conductivity, dielectric.
Interaction between Carboxy Methylcellulose and Salicylic Acid Solid Biopolymer Electrolytes
Authors: Rozali Mohd Lukhman Hakim , Ahmad Zakiyah , Isa M.I.N.
Published: June 2015

In this research, solid biopolymer electrolytes (SBEs) based on carboxy methylcellulose (CMC) has been prepared by doping different concentration of salicylic acid (SA) via solution casting technique. Fourier Transform Infrared spectroscopy was used to study the interaction between the host and ionic dopant. New peaks were observed at 1700, 2890, 2920 cm-1.The highest ionic conductivity achieved at room temperature is 9.50 × 108 S cm1 for CMC incorporated with 7 wt. % SA. In addition, the temperature dependence of the SBEs exhibit Arrhenius behavior.
Structural and Ionic Conductivity Studies of CMC Based Polymerelectrolyte Doped with NH4Cl
Authors: Ahmad Nur Hidayah , Isa M.I.N.
Published: June 2015

The present study aims to investigate the structural and ionic conductivity of carboxymethyl cellulose - ammonium chloride as proton conducting polymer electrolytes. The complexion of polymer electrolyte films has been confirmed via FTIR studies. The conductivity enhancement with the addition of ammonium chloride concentration was proved due to the increase in amorphous nature of the films as evidenced by XRD analysis. Impedance studies indicate that the highest ionic conductivity of 1.43 x 10-3 Scm-1 was observed with the addition of 16 wt.% ammonium chloride in polymer electrolyte system obtained at ambient temperature.
Influence of Molar Ratio of Citric Acid to Metal Ions on Structure, Microstructure and Electrical Transport Properties on Nanosized La0.85Na0.15MnO3
Authors: Pah Lim Kean , Cheong Kuen Hou , Shaari Abdul Halim , Hashim Mansor , Gan Albert Han Ming , Chin Hui Wei , Ng Siau Wei
Published: June 2015

In this paper, nanosized La0.85Na0.15MnO3 (LNMO) has been synthesized via sol-gel method by involving two major steps, first the complexation of citric acid (CA) with metal ions (MI) and second the polyesterification between CA and ethylene glycol (EG). The effect of molar ratio CA:MI varying from 2-4 on structure, microstructure and electrical transport properties of LNMO have been investigated by constant the amount of EG. All samples show single perovskite phase with hexagonal structure and space group R3c after sintering at 800°C for 10h. Sample of molar ratio 2.5 is observed to possess smallest grain sizes which yield high resistivity value compared with others, is suggested to originate from the increase of tunneling barriers (grain boundaries). The large low field magnetoresistance (LFMR) of about ~ -16% at 0.1T and low temperature confirmed the important role of grain boundaries in the nanosized LNMO.
Influence of Grain Size on the Thermal Diffusivity of Pt-SnO2 Ceramic
Authors: Aiza M.M. , Zaidan A.W. , Wan Mahmood Mat Yunus , Khamirul A.M.
Published: June 2015

Pt-SnO2 ceramics were prepared via solid-state route from a mixture of powders of (100-x) SnO2.x Pt (0≤ x wt %≤ 1). The samples were then sintered at 600, 800 and 1000 °C for 3 hours. The resulting samples were then characterized using Laser Flash Apparatus (LFA) for determining thermal diffusivity (α ) value. The measurements of α were carried out at room temperature up to 400 °C with the intervals of 50 °C. Experimental results showed that thermal diffusivity value is in the range of 5.0×10-7m2s-1 - 3.0×10-6m2s-1. We also show that larger grain size increases the thermal diffusivity of the ceramic. Data concerning the effects of additive amount, pore content, and temperature were also reported.
Effect of Sintering Temperature on Structural, Electrical and Magnetic Properties of La0.7Sr0.3MnO3
Authors: Pan Kai Yap , Shaari Abdul H. , Chen Soo Kien , Pah Lim Kean , Navasery Manizheh , Kechik Mohd Mustafa Awang
Published: June 2015

The influence of sintering temperature on structural, microstructure and transports properties of La0.7Sr0.3MnO3 (LSMO) prepared via sol-gel techniques is introduced. Sintering temperature of LSMO varied from 650°C to 950°C with the interval of 100°C. All samples show single phase structure with hexagonal setting. Refinement was done on the XRD data obtained. Microstructure investigation displayed an increment in average grain size of LSMO due to the grain growth promotion as the sintering temperature increased. Magnetization of all samples was enhanced by the grain growth promotion. Resistivity experienced a reduction trend and Tp shifted to higher temperature as the sintering temperature increased. All sintered LSMO exhibit LFMR effect at low applied field and low temperature.
Synthesis, Structural and Morphological Properties of Cadmium Oxide Nanoparticles Prepared by Thermal Treatment Method
Authors: Al-Hada Naif Mohammed , Saion Elias B. , Shaari Abdul H. , Kamarudeen Mazliana A. , Flaifel Moayad Husein , Gene Salahudeen A.
Published: June 2015

Cadmium oxide (CdO) nanoparticles was synthesized from an aqueous solution containing metal nitrate as a precursor and polyvinyl pyrrolidone (PVP) as a capping agent by simple thermal-treatment method. The as-synthesized sample has been calcined at various temperatures from 500 to 650 °C to remove the organic matters. The structure and morphology of the calcined oxide nanoparticles have been examined by X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. The results obtained supports the fact that the thermal treatment method utilized for the synthesis of CdO nanoparticles is certainly a very simple and low cost technique that requires no additional chemicals.
The Effect of Ni Catalyst on the Growth of Multi-Walled Carbon Nanotubes by PECVD Method
Authors: Lee Mai Woon , Mohammad Haniff Muhammad Aniq Shazni , Teh Au Shih , Bien Daniel C.S. , Chen Soo Kien , Talib Zainal Abidin , Shaari Abdul Halim
Published: June 2015

In this paper, the effect of nickel (Ni) catalyst on the growth of carbon nanotubes (CNTs) was studied where the CNTs were vertically grown by plasma enhanced chemical vapor deposition (PECVD) method. The growth conditions were fixed at a temperature of 700°C with a pressure of 1000mTorr for 40 minutes with various thicknesses of sputtered Ni catalyst. Experimental results show that high density of CNTs was observed especially towards thicker catalyst layers where larger and taller nanotubes were formed. The growth rate increases by ~0.7 times with increasing catalyst thickness from 4nm to 10nm. The nucleation of the catalyst with various thicknesses was also studied as the absorption of the carbon feedstock is dependent on the initial size of the catalyst island. From the Raman results, we found that only slight variation in the intensity ratio of G-band over D-band as increasing catalyst thicknesses. The minor difference in G/D ratio indicates that the catalyst thickness does not significantly influence the quality of CNTs grown.
Influence of NiO Nanoparticles on Physical Properties of TiO2 Doped Magnesium Ultra-Phosphate Glass-Ceramics
Authors: Abd Rahman S.F. , Sahar M.R. , Ghoshal Sib Krishna
Published: June 2015

Tuning the physical properties of inorganic glass-ceramics through controlled doping of magnetic nanoparticles is topically challenging. A series of glass-ceramic having chemical composition 75P2O5-17MgO-(3-x)TiO2-5Li2O with x = 0 to 3 mol% containing nickel oxide (NiO) nanoparticles (NPs) are prepared by melt quenching method (MQT) via heat treatment at 350 °C. The effect of NiO NPs on thermal and magnetization response are examined. X-Ray Diffraction (XRD) pattern confirm the amorphous nature of the samples. Differential Thermal Analysis (DTA) measurement shows the decrement of glass stability from 327°C to 295°C with the increase of titanium dioxide (TiO2) contents which are glass seem to be unstable. Significant increase in the magnetization is evidenced with the increase of NiO nanoparticles from 1.5 mol% to 2 mol%. The improved physical properties of these glass-ceramics suggest their usefulness in photo-electronic.
Surface Modification of Graphitic Mesoporous Carbon Adsorbent by Chemical Oxidation for Removal of Basic Dye from Aqueous Solution
Authors: Endud Salasiah , Razman Nur Izzatie Hannah
Published: June 2015

A graphitic mesoporous carbon-based material (GMC) was prepared using a nano-casting process by using SBA-15 as a hard template and sucrose as a carbon precursor. Modification of GMC was carried out by chemical oxidation with nitric acid in order to generate surface functionalities. The oxidized GMC material was then used as adsorbent for Basic Red 2 (BR2) in aqueous solutions. The morphology, pore structure, and surface functional groups of GMC samples were evaluated by field emission scanning electron microscopy (FESEM), Brunauer-Emmett-Teller method (BET), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and Boehm titration. N2 adsorption-desorption analysis revealed a type IV isotherm characteristic of mesoporous materials with BET surface area approximately 1000 m2g-1 and pore volume 0.9 cm3g-1. The effects of different adsorption parameters such as initial pH, initial dye aqueous solution concentration and temperature on BR2 removal were investigated. After modification, the BET surface area slightly decreased but the adsorption capacity of BR2 increased with optimum adsorption in 200 ppm initial concentration, pH of 10 at 60 °C.
Effect of Strontium on the Catalytic Activity and Physicochemical Properties of Ru/Mn Catalysts for CO2 Methanation Reaction
Authors: Toemen Susilawati , Ali Rusmidah , Wan Abu Bakar Wan Azelee
Published: June 2015

The recycling technology by the catalytic conversion offers a very promising technique for reducing greenhouse CO2 gas from flue gases of coal burning power plant by converting the carbon dioxide gas to methane. The methane produced from the reaction can be used as other fuel to run turbine for electricity generation. Therefore, the strontia based catalysts was prepared by impregnated with RuMn/Al2O3 catalyst and then calcined at 1000°C for 5 hour. Strontia catalyst is an effective material because of its highly basic properties which could enhance carbon dioxide adsorption and chemisorption on the catalyst surface but not been widely explored. The result obtained revealed that the addition of Sr to RuMn/Al2O3 as based catalyst had increased the catalytic activity and found to be more active for promoting the CO2 methanation reaction. Under reducing pretreatment at 300°C, the activity of CO2 conversion increased about 30.98% which is from 50.45% over RuMn-65/Al2O3 catalyst to 73.10% over RuMnSr-65/Al2O3 catalyst with 40% of methane yielded at reaction temperature of 210°C. The Sr addition did not modify the crystalline structure of the catalyst but gave higher surface area, smaller particle size and high metal dispersion as well as increased the degree of reduction and CO chemisorption.
New Polyester Nanofiltration (NF) Membrane for Humic Acid Removal
Authors: Jalanni Nurul Ain , Seman Mazrul Nizam Abu , Faizal Che Ku Mohammad
Published: June 2015

Interfacial polymerization of a thin film composite (TFC) layer on top of a miroporous support membrane or other porous substrate is one of adequate method to form nanofiltration membrane in order to remove humic acid. Ultrafiltration (UF) polyethersulfone (PES) was used as membrane base support. Reaction occurred on the surface of membrane between two phase which are triethanolamine (TEOA) and trimesoyl chloride (TMC) as aqueous solution and organic solution respectively. Membrane that produced characterized by permeability, charged solutes rejection including salt solutions (NaCl and Na2SO4) and humic acid removal. Properties of membrane can be attributed with the changes of monomer concentration and reaction time. Pure water flux Jw for membranes calculated as a function of applied pressure to membrane ΔP. Thus, flux increased linearly with operating pressure is applied to membrane where meets Hagen-Poiseuille equation and gradient of every straight line give pure water permeability data. The variation of reaction time (15, 25 and 35 min) at 8% (w/v) monomer concentrations can affect the properties of the membrane produced and decreasing water permeabilities. The rejection order of the membrane changed from 0.001 M Na2SO4 > 0.1M Na2SO4> 0.001M NaCl > 0.1M NaCl. Humic acid removal resulted almost fully rejection showed that nanofiltration membrane is one of the best methods in water treatment technology.
Growth of Hydroxyapatite on Strontium Oxide Modified Bioactive Glass
Authors: Ridzwan H.J.M. , Jamil N.H. , Syamsyir S.A. , Razali W.A.W.
Published: June 2015

The bioactive glasses of SiO2-CaO-P2O5-SrO system have been prepared by a quick alkali mediated sol-gel method. The prepared bioactive glass of 1, 3, 5 wt% of SrO (coded: SR1, SR3, SR5, respectively) were characterized by SEM, XRD and FTIR. XRD pattern of all glasses calcined at 700°C in air confirmed that the calcined bioactive glass generally existed in amorphous state. The samples were immersed in simulated body fluid (SBF) to investigate the presence of hydroxyapatite (HA). All bioactive glass samples can induce the formation of hydroxyapatite (HA) as verified by SEM and XRD.
Optical Absorption of Er3+/Nd3+ Codoped Lithium Niobate Tellurite Glass
Authors: Nurhafizah Hasim , Rohani Md Supar , Sahar M.R. , Ghoshal Sib Krishna
Published: June 2015

Keywords: Tellurite Glass, UV-Vis-NIR, absorption, Urbach energy. Abstract: To improve the optical behaviour of Lithium Niobate Tellurite glass with rare- earth dopant are the important issue from application and device perspectives. Er3+ and Nd3+ doped tellurite glasses of molar composition (70-x-y)TeO2 – 15Li2CO3 – 15Nb2O5 – xEr2O3 – yNd2O3 system (x = 0 mol % and 1.0 mol %) (0 mol % ≤ y ≤ 1.0 mol %) have successfully been made by using melt quenching technique. The physical properties of the glass sample are obtained. From Ultraviolet- Visible- Near Infrared (UV-Vis-NIR) Spectroscopy, it is observed that the spectrum consists absorption peaks which corresponded to transitions from both ground state of Erbium, 4I15/2 to the excited state of 4I15/2, 4I13/2, 4I3/2, 4I11/2, 2H9/2, 4I9/2, 2H11/2, 4S3/2, 2H11/2 and 4F7/2 respectively and Neodymium, 4I9/2 to the excited state of 4I15/2, 4I15/2, 4I3/2, 4F9/2, 2G7/2, 2G9/2 and 2G11/2 respectively. The indirect band gaps obtained from the above dependence are the interband transitions, but later it involves the phonon interaction where the values of indirect optical band gaps lie between 2.84 eV to 3.12 eV as the Nd2O3 content increase. The Urbach energy for the glass system decreases from 0.31 eV to 0.21 eV as the Nd2O3 content increase.
Optical Absorption of Erbium Doped Zinc Phosphate Glass Containing Fe3O4 Nanoparticles
Authors: Buchori Puzi Anigrahawti , Sahar M.R. , Rohani Md Supar , Ghoshal Sib Krishna
Published: June 2015

Modifying the optical properties of rare earth doped phosphate glasses in a tunable fashion via the embedment of magnetic nanoparticles (NPs) is challenging for magneto-optic devices. Glasses with compositions (69-x)P2O5-30ZnO-1Er2O3-(x)Fe3O4, where x = 0 to 1.5 mol% are prepared by conventional melt quenching method. The Fe3O4 NPs concentration dependent density, molar volume, refractive index and optical properties are determined. Density and molar volume shows strong correlation with structural alteration in the presence of NPs. The XRD spectra confirm the disordered nature of the glass and TEM micrograph display the presence of spherical NPs with average size ~26 nm. The optical band gap and Urbach energy calculated from the room temperature absorption spectra recorded in the range of 350-1700 nm reveal significant improvement. The density and refractive index increases and the molar volume decreases with the increase of Fe3O4 contents. The energy band gap for direct and indirect transitions varies in the range of 4.47-3.64 eV and 4.27-3.53 eV, respectively. The Urbach energy increases from 0.15 to 0.19 eV as the NPs concentration increases from 0 to 1.5 mol%.
Optical Properties of Oxy-Chloride Tellurite Glass: Role of Samarium Ions
Authors: Ghoshal Sib Krishna , Mohamad Zake Nurul Syuhada , Arifin Ramli , Sahar Md Rahim , Rohani Md Supar , Hamzah Khaidzir
Published: June 2015

. Achieving tunable optical properties of inorganic glasses via optimized doping of rare earth ions is ever-demanding in photonics. Control and inhibition of luminescence quenching, nonradiative decay and multi-phonon relaxation responsible of reduction of optical performance remains challenging. Doping/co-doping of different rare earth ions, variation of modifiers and embedding metallic nanoparticles (NPs) are thought as alternative routes to enhance optical response are still underway. We examine the influence of samarium ion concentrations on the optical properties of oxy-chlorite tellurite glasses of the form (70-x)TeO2-15MgO-5Li2O-10LiCl-xSm2O3 with 0.0 x 2.5 mol% prepared using melt-quenching method. The structural and optical characterizations are performed via X-ray diffraction (XRD), Ultraviolet-Visible (UV-Vis) absorption and photoluminescence (PL) spectroscopy. The glass density increased from 4.509 - 4.770 with the increase of Sm2O3 contents from 0.0 2.5 mol %. The XRD spectra confirm the amorphous nature of the glass. The absorption spectra exhibit nine prominent peaks corresponding to the transitions from the ground to excited states and the PL spectra reveal four peaks. The optical energy band gap for direct and indirect transitions are increased and Urbach energy decreased from 3.448 - 3.497, 3.165 - 3.232 and 0.217 - 0.175, respectively with the increase of Sm3+ ion concentrations. Furthermore, the significant enhancement in UV-Vis and PL response display the strong influence of samarium ion on optical and structural properties. The mechanism responsible for enhanced optical properties are analyzed and discussed. The results suggest that our careful experimental studies may contribute towards the development of tellurite glass based solid state lasers.
Temperature Dependence on Dielectric Response of La0.7Ba0.3Mn0.4Ti0.6O3 Ceramic
Authors: Sinin Aaliyawani Ezzerin , Primus Walter Charles , Shaari Abdul Halim , Talib Zainal Abidin , Hamdan Sinin
Published: June 2015

Ceramic sample of La0.70Ba0.30Mn0.40Ti0.60O3 oxide has been prepared by the conventional solid-state reaction method. The sintered sample was characterized by using x-ray diffraction (XRD) and low frequency LCR meter. XRD result shows that the sample has a cubic structure with the existence of impurity phase. The dielectric properties of La0.70Ba0.30Mn0.40Ti0.60O3 measured from room temperature to 200°C shows that the dielectric permittivity is temperature dependence with strong dispersion at low frequencies. A circuit model based on the universal capacitor response function is also being used to represent the dielectric properties of the sample.
Temperature Stability and Physical Properties of Bi2O3-B2O3-ZnO-RHA Glass System
Authors: Nabilah Razali Nur Ain , Mustafa Iskandar Shahrim , Ibrahim Abdul Razak , Rosli Mohd Mustaqim , Kamari Halimah Mohamed
Published: June 2015

Rice husk ash (RHA) is a product from the burning of the rice husk and it become a significant material for glass preparation due to high amount of amorphous silica that can be produced. From the recent studies, the highest amount of silica is observed at 550°C at 6 hours which is 99.36% by XRF detection. Nevertheless, the amount of silica decreasing proportionally if the temperature profile is higher than 550°C and the time taken is more than 6 hours. Quaternary glasses are prepared using melt-quenching method using the highest amount of silica from RHA combined with Bismuth Oxide (Bi2O3), Boron Oxide (B2O3), and Zinc Oxide (ZnO). The ratio of quaternary glass that used are 30%SiO2: 20%B2O3: xZnO : (50-x)%Bi2O3 (% mole) ; where x= 10,20,30,40. The physical properties and glass transition temperature (Tg) profiles are determined using standard measurement instrument. Moreover, the density measured will enhance the verification of Oxygen Packing Density for prepared quaternary glasses.
The Role of Samarium Ion in Optical Properties of Magnesium Tellurite Glass Embedded with Silver Nanoparticles
Authors: Nurulhuda M.Y. , Sahar M.R.
Published: June 2015

A series of tellurite glass based on composition (89.6-x)TeO2-10MgO-xSm2O3-0.4AgCl where 0.2x1.0 have successfully been prepared by melt-quenching technique. The optical behaviour has been examined as a function of Sm2O3 content by using UV-Visible Spectroscopy in the range of 200-900 nm. The absorption studies revealed that the indirect and direct optical energy band gap is in the range of 2.81-3.11 eV and 3.16-3.45 eV, respectively. Meanwhile, Urbach energy, E is in between 0.18-0.24 eV. The increasing in samarium ion up to 0.4 mol% of Sm2O3 result in an increment of optical energy band gap, but gradually decreases beyond 0.4 mol%. All the results will be discussed with respect to Sm2O3 content.
Thermal and Structural Properties of Erbium/Neodymium Co-Doped Lithium-Magnesium-Tellurite Glass
Authors: Arifin Ramli , Roslan Syaridatul Akmar , Sahar M.R. , Ghoshal S.K. , Hamzah K.
Published: June 2015

Detailed characterizations of inorganic glasses via optimized rare earth doping/co-doping are challenging. Tellurite glasses with composition (78-x)TeO2-10Li2O-10MgO-2Nd2O3-xEr2O3, (where x = 0.4 to 2.0 mol%) are prepared by melt-quenching technique. The effects of Er2O3 concentration on the thermal stability and structural properties are examined. The X-ray diffraction pattern confirms the glassy nature of all samples. The temperature of glass transition (Tg), crystallization (Tc), melting (Tm) and the difference (Tc-Tg) are determined by differential thermal analyser (DTA). The values of Tc, Tg and Tm are found to vary in the range of 419-430 °C, 300-345 °C and 885-890 °C, respectively. The glass sample with 0.4 mol% Er2O3 shows highest thermal stability. The FTIR spectra measured in the range of 400 - 4000 cm1 exhibits two major absorption peaks around 1600 - 3600 cm1 and 900 - 1200 cm1 assigned to the stretching vibrational mode of OH and Te-OH respectively. Improvements in the optical and thermal properties due to co-doping may be useful for the development of tellurite glass based photonics.
Aqueous Corrosion Investigation of Yb Doped Lead Oxychloride Tellurite Glass
Authors: Hamzah Khaidzir , Yassin M. Abdullah Izat , Suffian Ahmad Farhan , Sahar Md. Rahim , Ghoshal Sib Krishna
Published: June 2015

Series of glass based on (80-x)TeO2-10PbO-10PbCl2-xYb2O3 where 0.0 ≤ x ≤ 3.0 were successfully prepared via melt quenching technique. The corrosion rate measurement was carried out by immersing the glass in various pH solutions in the range of pH 2 to 11. The alteration in surface morphology and structural characteristics was examined using field emission scanning electron microscopic and X-ray diffraction measurements. The corrosion investigations showed that the corrosion rate of the glass decreased over time due to the formation of protective layer on the glass surface. Furthermore, the increase in Yb amount in the glass network was found to enhance the corrosion resistance. This attributed to the enhancement of glass compactness. However, as the amount reached 2 mol%, the ability to resist corrosion decreased due to inability of Yb to participate in the structure. The FESEM micrographs indeed revealed the differences of surface morphology of glass after immersion in various pH solutions. It is demonstrated that the corrosion of acid and alkali occurred differently where acidic attacks were faster compared to alkali and distilled water.
An Investigation of Structural and Electronic Properties of Novel Cathode Material Li2MnP2O7 and its Delithiated Li2-xMnP2O7 (x=1,2): A First Principle Study
Authors: Rasiman Mohd Sazwan Affendi , Badrudin Fadhlul Wafi , Yaakob Muhamad Kamil , Taib M.F.M. , Marwan Bin Ali Abdul Malik , Yahya Muhd Zu Azhan , Hassan Oskar Hasdinor
Published: June 2015

First-principles calculations based on the DFT approximated by GGA-PBEsol scheme has been utilized to predict the structural and electronic properties of Li2MnP2O7 and possible delithiated Li2-xMnP2O7 (x=1,2) configurations. Our results show that the approximation provided more reasonable predictions on the structural consistent with experiments. The calculated voltage profile underestimate the experimentally observed redox potential. Density of States (DOS) results reveals the insulator behavior of Li2MnP2O7.
Annealing Effect on Photoacoustic Characterization of NiSe Metal Chalcogenide Semiconductor Using Phase Signal Analysis
Authors: Chin Pik Yee , Talib Zainal Abidin , Mahmood Mat Yunus Wan , Chyi Josephine Liew Ying , Sabli Nordin , Chung Bin Chang
Published: June 2015

Nickel selenide (NiSe) has been synthesized by solid state method and annealed at five different temperatures, ranging from 323 K to 823 K. The annealing effect on NiSe thermal and carrier transport properties were investigated by using open-cell photoacoustic technique. From analysis of its phase signal-frequency, thermal diffusivity, carrier diffusion coefficient, surface recombination velocity and recombination lifetime of the NiSe was determined. The results show that with increasing of the annealing temperature of NiSe sample, the thermal diffusivity and the carrier diffusion coefficient increased. The surface recombination velocity was decreasing as the annealing temperature of the sample increased. The increasing of annealing temperature of the sample also affected the trend of band-to-band recombination lifetime.