bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Study for the Dissolution of Bone Ash-Derived and Artificial Hydroxyapatite
Authors: Lee Jong Kook , Kim Heong Jun , Jang Woo Yang
Published: March 2012

Hydroxyapatite (HA) ceramics were prepared from the bone ash which is mostly used as animal feeds or raw materials. Dissolving behaviors of the HA in buffered water were investigated and compared with commercial HA for further use as biomaterials. HA ceramics were prepared by soaking the bone ash in 0.1 M of NaOH solution at 80°C for 4 h. The ash was calcined at 800°C for 1 h to completely remove organics, and then sintered at 1200°C for 1 h under moisture protection. The bone ash derived-HA consists of mostly HA and small amounts of α-tricalcium phosphate, calcium oxide phosphate, magnesium oxide and calcium oxide. After polishing the HA ceramics, they were immersed in buffered water at 37°C for 3 and 7 days. We previously found that grain boundaries of synthetic HA were intensively dissolved in buffered water. On the other hand, the bone ash derived-HA shows high stability in liquid environment with immersion time compared with commercial HA.
Effect of Flame Retardant on Combustion and Mechanical Properties of Bamboo-Fiber Based Composites
Authors: Liu Shu Jun , Han Yan Ming , Zhu Rong Xian , Chu Fu Xiang , Yu Wen Ji
Published: March 2012

Bamboo fibrosis veneers were impregnated with diammonium hydrogen phosphate, and the content of diammonium hydrogen phosphate was 8%, 13% and 17%, respectively. Then bamboo-fiber based composites were prepared with PF resin adhesive. Combustion and mechanical properties of these fire retardant bamboo-fiber based composite were measured. The result showed that: 1) with the increase of diammonium hydrogen phosphate content, combustion properties increased while mechanical properties fell down, 2) when the diammonium hydrogen phosphate content reached 17%, the heat release rate, total heat release, effective heat of combustion, mass loss rate and ignition time went down by 70.1%, 68.8%, 68.5%, 32.0% and 27.1%, compared with the untreated bamboo-fiber based composites, meanwhile, 3) the MOR was 159.5MPa, MOE was 21241.5MPa and IB was 3.51MPa.
Effects of Calcination Temperature on Electrospun Silica Fibers
Authors: Pramuansub Nuttaya , Jittangprasert Piyada , Wanakamol Panitarn
Published: March 2012

Silica fibers have been fabricated via sol-gel reaction and electrospinning. The precursor solution was prepared from tetraethyl-orthosilicate (TEOS), ethanol and aqueous hydrochloric acid. The viscous solution was electrospun at 15kV applied voltage and 20 cm tip-to-collector distance. The process yielded nonwoven sheet of silica fibers with good mechanical integrity. The silica fiber specimens were calcined at different temperatures: 400°C, 600°C and 800°C. Scanning electron microscope (SEM) observation reveals smooth and long fibers with average diameter below 0.5μm for all samples, both as spun and calcined. Fourier transform infrared spectroscopy (FT-IR) spectra show effects of calcination temperature on chemical structure of the fibers. Calcination results in the removal of organic residuals and leaving mostly silica content
High Performance Fiber Composites with Enhanced Energy Absorption for Underground Construction
Authors: Farjadmand Massoumeh , Safi Mohammad
Published: March 2012

In order to provide higher energy absorption capacity in fiber reinforced composites, it is normally required to use more volumes of fibers. This leads to economical limitations as the fiber content usually controls the cost of the composite mix. This research has tried to enhance the energy absorption capacity of the composite while keeping the fiber content constant or at the minimum possible value. A series of laboratory tests were conducted in Iran and Turkey with the same material and fiber type and some recommendations for achieving the optimized results were proposed. Beam and panel tests were used to account for the energy absorption and the results were used for tunnel lining design.
Properties of Compatibilized SAN/NR Blends
Authors: Rojsatean Jareenuch , Suttireungwong Supakij , Seadan Manus
Published: March 2012

The blend of poly(styrene-co-acrylonitrile) (SAN) and natural rubber (NR) is immiscible and incompatible which lead to poor mechanical properties. Many methods can be carried out to improve the compatibility. In this work, the potential of various reactive compatibilizers in SAN and NR blend was explored. The morphological and mechanical properties were compared. The melt blending of SAN and NR were prepared in an internal mixer with various types of reactive agent such as styrene-co-maleic anhydride (SMA), maleic anhydride (MA), peroxide and mixed reactive agents. The morphological textures of the blends were investigated by scanning electron microscope. Mechanical properties including tensile strength, impact strength and elongation at break were measured. The results of morphological observations revealed that SAN/NR blend with reactive agent, the mixture of SMA and MA show the smallest and the most uniform dispersed NR particles, where the size of NR particle is about 1 µm. The mechanical properties of the blends revealed impact strength and elongation at break were increased with addition of reactive agents. SAN/NR blend with the mixture of SMA and MA showed the highest elongation at break but it had lower impact strength than the blend with SMA.
Effects of Long Chain Cellulose Ester on Mechanical Properties of Polylactic Acid Reinforced with Microcrystalline Cellulose
Authors: Suchaiya Voravadee , Aht-Ong Duangdao
Published: March 2012

Long chain cellulose ester (LCCE) synthesized by acylation reaction via microwave process was used as a compatibilizer for banana stem microcrystalline cellulose/polylactic acid (BS MCC/PLA) composite. The proper reaction time and power output for LCCE synthesis were 150 second and 160 watt, respectively, which resulted in the highest weight increase (%) of LCCE synthesis. The FT-IR and NMR results confirmed that long chain acyl ester was grafted on cellulose structure. The degree of substitution (DS) of LCCE was 2.41. The BS MCC content was fixed at 40wt% while LCCE content was varied from 0-9 wt%. The Tensile properties properties of BS MCC/PLA composites with or without LCCE were studied by tensile test. The results revealed that the addition of LCCE enhanced the elongation at break of 40wt% BS MCC/PLA composite owing to the improvement of compatibility between PLA and MCC, particularly the addition of 5wt% of LCCE which led to the highest elongation at break. However, when the addition of LCCE was greater than 5wt%, the elongation at break was slightly decreased because of the small aggregation of BS MCC and LCCE in PLA matrix as supported by morphological analysis. Nevertheless, the addition of LCCE contributed to the decrease in tensile strength and Young’s modulus of 40wt% BS MCC/PLA composite slightly because of the decreasing of crystallinity in PLA composite.
Composites of Polypropylene/Pottery Stone/Magnesium Oxysulfate
Authors: Chuayjuljit Saowaroj , Rupunt Thitima , Karnjanamayul Thatisorn
Published: March 2012

The impact strength, thermal stability and morphology of polypropylene (PP) composites filled with pottery stone (PTS) and magnesium oxysulfate (MOS) were investigated. PP/PTS composites were prepared by melt mixing of PP with four loadings of PTS (5, 10, 15 and 20 phr) and each PP/PTS composite with two loadings of MOS (3 and 5 phr) on a twin screw extruder, followed by injection molding into the impact test specimens. The SEM images show a particulate form of PTS particles and a needle-shaped particle with high aspect ratio of MOS. It is found that the impact strength of PP increased with increasing PTS and MOS loading levels. This is because PTS and MOS provide high ability to transfer energy from one phase to another. The thermal stability of PP was improved by shifting the Tonset, Tend set and %char residue towards higher values. Moreover, SEM images of the fractured surfaces show that PTS and MOS are well dispersed in the PP matrix.
The Chemical Modification of Waste PET and its Application for a Wood-Polymer Composite Binder
Authors: Ruamcharoen Polphat , Phetphaisit Chor Wayakron , Bumee Ratree , Ruamcharoen Jareerat , Niyomdecha Bussara , Nillawat Supattra
Published: March 2012

The application of hydroxyl terminated polyethylene terephthalate (PET-OH) as a starting pre-polymer to react with polymeric methylene di-isocyanate (p-MDI) for synthesis of polyurethane as a wood-composite binder was studied. The PET-OH was modified from waste polyethylene terephthalate (PET) bottles by glycolysis reaction. The effect of weight ratios of binder and rubber-wood sawdust particles and the mole ratios of hydroxyl (OH) of PET-OH and isocyanate (NCO) of p-MDI on mechanical properties were investigated. The properties of wood-polymer composites from PET-OH were also compared with the polyurethane composites from polyethylene glycol (PEG) as a commercial polyol. It was found that mechanical properties of wood-polymer composites increased with the increase of binders and polyol contents and then decreased and PET-OH showed the greater properties than PEG. The ratio of wood particle and the binder of 60:40 by weight and the ratio of OH and NCO of 0.01:1 by mole gave the best mechanical properties.
Analysis of Laminate Configuration on Impact Properties of Glass Fibre Epoxy Nanocomposites
Authors: Thiagarajan A. , Palaniradja K. , Mathivanan N. Rajesh , Naresh M.
Published: March 2012

The impact behaviors of glass fibre reinforced/epoxy nanocomposites were studied by experimental using instrumental falling weight testing machine at three different energy levels. Two types of laminates were prepared by hand lay-up method with varying nanoclay into the epoxy in a 1%, 3% and 5%, respectively. The structures of nanocomposites were studied using X-ray diffraction (XRD). It was found that the nanoclay was orderly exfoliated in the epoxy resin. The impact properties of maximum load and energy absorption were determined. It was observed that addition of 3% nanoclay into the epoxy, the maximum load was enhanced by 32% and energy absorption by 24% at the energy level of 24.89J. The impact fractured surface morphology of the glass fibre/epoxy nanocomposites was analyzed using scanning electron microscopy (SEM).
Tensile Properties and Morphology of Natural Rubber-Kaolinite Organoclay Composites
Authors: Ruamcharoen Jareerat , Chotisuwan Suawapa , Ruamcharoen Polphat
Published: March 2012

Natural rubber (NR) based composites with various amount of kaolinite were performed via the latex compounding method. The aim of this work was to investigate the effect of clay modification and clay contents on tensile properties of the NR composites. The kaolinite clay was modified by an ion exchange reaction with octadecylammonium ion. FTIR spectrum of modified kaolinite revealed the evidence of octadecylamine signals. The modified kaolinite investigated using SEM represents the platelet shape and the size distribution of organoclay particles is consistency. The tensile moduli and strengths of unmodified clay composites tend to decrease whereas those of modified clay composites are improved and increased with the modified kaolinite contents. Swelling resistance in non-polar solvent of the NR/ODA-kaolinite composites is greater than that of NR and NR/kaolinite composites. The morphological study by the SEM suggested that the modification of kaolinite clay helped improve the dispersion of clay in rubber phase. These results reflected that the dispersion of silicate layers was the key parameters in enhancing the physical properties of the composites.
Fuzzy Control Scheme for Transportation of Ultra-Thin Flexible Substrates with Variable-Section
Authors: Shao Lin , Qin Hai Chen , Chen Jian Kui , Tao Bo
Published: March 2012

This paper proposes a fuzzy control scheme to achieve the high-precision and high-speed continuous transportation of ultra-thin flexible substrates with variable-section. A tension control model is presented based on the torque balance of pinches. In the model, the flexible substrate is regarded as a parallel spring-damp system, challenged by the dynamics associated with low-tension operation, besides the time-variation resulted by the variable-section. A fuzzy control algorithm is designed for the tension controller. Finally, the analysis in dynamic performance of the whole system is done using MATLAB toolbox. The simulation results show that the fuzzy control algorithm presented is effective to the tension even in transient state.
Microscopy Observation on Nanocellulose from Kenaf Fibre
Authors: Surip Siti Norasmah , Wan Jaafar W.N.R. , Azmi N.N. , Anwar U.M.K.
Published: March 2012

Conventional fibre size has large surface area for binding site while nanocellulose posses higher surface area thus making more available binding site for fibre-matrix interaction. Kenaf has poor surface properties before treated. Treatment was applied to overcome this problem with alkali followed by acidic treatment. The nanocellulose has been produced from kenaf core (hibiscus cannabinus) by chemi-mechanical method. The fibre was treated with alkali followed by acidic treatment (HCl). Treated fibres were mechanically process by using pulverisette & cryocrushing to reduce the fibre size. The nanocellulose fibres were observed under Scanning Electron Microscope (SEM). The result convinced that chemi-mechanical method is a new technique for producing high yield kenaf nanocellulose.
Compression Behavior of Adhesive Butt Joints of Aluminum Hexagonal Core Sandwich Panels with Different Edging Configurations
Authors: Rajkumar Sivanraju , Ravindran D. , Arul Raj P.K. , Hariprasath V.
Published: March 2012

Aluminum honeycomb core sandwich panels are now commercially available and are widely used as light weight materials in aircraft, naval and other applications because of their high strength to weight ratio, high bending stiffness, fire retardant resistance, insulation properties and sound attenuation properties. In all these applications extensive joining is encountered in fabricating the panels to complex shapes. This paper has investigated various edging and configuration details to secure butt joints with adequate soundness through adhesive joining methods. The compression strength of the joints has been assessed experimentally. The configuration of each butt joint is discussed and best combinations of edging and configuration are recommended for successful fabrication of complex assembles with aluminum honey core sandwich panels.
Properties of Ag Doped CdTe Thin Film Prepared by Stacked Elemental Layer (SEL) Method
Authors: Shanmugan Subramani , Mutharasu Devarajan , Zainuriah Hassan
Published: March 2012

Thin films of elements (Cd,Te,Ag) were layered as a stack (Te/Cd/Te/Ag/Cd) for doping process with different Ag and Cd thickness by SEL method. The XRD results were depicted the presence of Cubic phase CdTe with (111) orientation along with Ag2Te, CdAgTe, AgTe phases. The peaks related to Ag atom at higher concentration evinced the presence of non-reacted Ag atoms on the surface with higher Ag concentration. The observed results showed the growth of CdTe crystals in (111) orientation with high Ag concentration. The AFM results of the annealed stack were clearly indicated the influence of Ag concentration in grain growth as well as surface roughness. Photo-resistivity studies of the annealed stacks also revealed the effect of Ag concentration in reducing the resistance with difference light sources. The observed results suggested that the SEL method could be used for effective doping of transition metals to achieve desired properties.
Silica Preform Neck-Down Shape and Glass Fiber Drawing in Optical Fiber Manufacturing Process
Authors: Kim Kyoung Jin
Published: March 2012

The glass fiber drawing from the silica preform in a draw furnace is one of the important processes in a mass manufacturing system of optical fiber. When a preform of cylindrical shape is fed and heated in draw furnace and very thin glass fiber is pulled from the softened preform by applying a proper amount of draw tension, the preform experiences a drastic diameter change or neck-down shape. In this paper, neck-down shape formation and glass fiber drawing in heated preform is numerically modeled into one-dimensional formulation of momentum balance in order to examine the effects of the silica preform temperature such as the maximum temperature of preform and the cooling rate of glass fiber at high fiber drawing speed. The results show the typical shape of preform neck-down and the draw tension which is comparable to the industry value of approximately 100 g. Also, it is found that the axial location of glass fiber re-solidification sensitively depends on the cooling rate, while the draw tension is insensitive to the cooling rate of glass fiber.
Optimizing Layout and Amount of Eco-Industrial Demonstration Parks in Jilin Province, China
Authors: Cao Yong Hong , Zhang Feng Rong
Published: March 2012

A great number of Eco-industrial demonstration parks (EIDPs) have been built across China in order to set examples for the full implementation of circular economy and eco-industry. However, a series of problems appear, such as confusing definitions on the two concepts of Eco-industrial parks (EIPs) and EIDPs, disorderly macro layout of EIDPs, lacking a regional network system of EIDPs, etc.. The article holds that EIDPs, besides the basic characteristics of EIPs, should highlight the exemplary role. The location and amount of EIDPs in those regions should be decided through macro layout and amount optimization of EIDPs. In light of this view, a case study in Jinlin Province is applied. The net of EIDPS can set examples for the construction of EIPs across the province, and also avoid redundant construction as well as cut the cost of demonstration.
The Effects of Injection Moulding Processing Parameters and Mould Gate Size towards Weld Line Strength
Authors: Othman Mohd Hilmi , Shamsudin Shazarel , Hasan Sulaiman , Rahman Mohd Norhafiz Abd
Published: March 2012

Plastic moulded parts should have good mechanical properties and free from defects. Tensile behaviour of plastics plays an important role in defining the quality of injection-moulded products. In this study, numerical simulation (Cadmould) was employed to investigate the influence of gate sizes as well as the injection moulding parameters towards the occurrences of weld lines at Acrylonitrile Butadiene Styrene (ABS) specimens. This research begins from the simulation, fabrication of mould, practical injection process and tensile test. The double gates mould was used to present the weld line defects. The result shows that the smaller gate size produces less weld line in plastic parts, which was verified through simulation process. The optimal parameter setting that produced good tensile strength specimens was also validated experimentally in this research
Body Armor Technology: A Review of Materials, Construction Techniques and Enhancement of Ballistic Energy Absorption
Authors: Hani A.R. Azrin , Roslan A. , Mariatti J. , Maziah M.
Published: March 2012

Body armor is a material to protect body from injury of various kind of high speed projectile impact velocity in combat or other dangerous situation. Researchers were found to actively research and exploring new body armor technology due to the invention of new firearms. Furthermore, they were also competing in developing ballistic panel which is lighter in weight, more flexible and comfort in use, cheaper in cost and manufacturability. This paper reviews the body armor commercial and current development materials, structure and construction techniques involved and related works on enhancing ballistic energy absorption.
Tool Inclination Angle Change Rate Control in Five-Axis Flat-End Milling
Authors: Kiswanto Gandjar , Ricko Vinsensius , Suntoro S.
Published: March 2012

Five-axis milling is used in the machining of complex shaped surfaces in a wide range of industries. In five-axis milling, one can adjust inclination angle to adapt such machining condition, e.g. to give high material removal and/or to avoid gouging. Choosing an appropriate inclination angle is difficult especially for complex parts with varying surface curvature. On the one hand, a small inclination angle is recommended to have good surface roughness and small scallop height. On the other hand, some regions may need much larger minimum inclination angle compared to the others to avoid gouging. The trade off for this is to have, in practice, a varying minimum (which is considered to be optimal) inclination angle along the tool path, so that while machining, the tool is dynamically adapted to be as close as possible to the surface without gouging. However, applying inclination angle change over some distances influences the quality of machined surface. This paper presented a method to control such inclination angle change to improve part accuracy. Some experimental were conducted to see the results and compared with the one when inclination angle change is not controled. The propose method effectively reduces the surface deviation thus improve part accuracy. More details about this study are presented in the paper.
Effect of Clay on the Properties of Polyoxymethylene/Clay Nanocomposites
Authors: Wacharawichanant Sirirat , Sahapaibounkit Paramaporn , Saeueng Unchana
Published: March 2012

This work investigated the effect of montmorillonite clay surface modified with 25-30 wt% trimethyl stearyl ammonium (clay) on mechanical, thermal and morphological properties of polyoxymethylene (POM)/clay nanocomposites were investigated. The results showed that POM/clay nanocomposites could maintain or decrease their tensile strength for a certain clay loading range. The Young’s modulus of the nanocomposites increased by adding clay in a range of 0.5-4 wt% while the impact strength showed an increase in a range of 0.5-2 wt%. The percent strain at break of the nanocomposites decreased with increasing filler content. The thermal degradation temperature decreased with an increase of clay content thus the addition of clay did not improve the thermal stability of POM. The microstructure of neat POM and POM/clay nanocomposites was observed that the dispersion of clay was a good in POM matrix at low clay content. The nanocomposites formed the intercalated structure with clay, and the intercalated clay stacks were distributed uniformly in the nanocomposite. The increase of clay content observed increasing of brittleness in POM/clay nanocomposites.
Shear Mechanical Properties Characterization of Material via Ultrasound Vibrometry
Authors: Chen Ke , Lin Jiang Li , Yin Guang Fu , Zheng Yi
Published: March 2012

Measurement of mechanical properties is very important in material science research area. Shear mechanical properties can be obtained from ultrasound vibromery method. Generally, ultrasound vibrometry is based on Voigt model which cannot describe some viscoelastic material accurately. Our method is based on Zener model, and more precise description of mechanical behavior can be measured. In our work, finite element method and experiment are conducted to validate our approach. Shear wave velocities at harmonics in finite element simulation are very close to the theoretical value and the fitting results from experiment demonstrate that our method has better ability to characterize some materials.
Investigation of Correlation between Polishing Characteristic and Pad Roughness during Chemical Mechanical Planarization Process
Authors: Kim Hojoong , Kim Andy , Kim Tae Sung
Published: March 2012

The Chemical mechanical planarization (CMP) process has become a primary planarization technique required for the manufacture of advanced integrated circuit (IC) devices. As the feature size of IC chips shrinks down to 65 nm and below, the role of CMP as a robust planarization process becomes increasingly important. In this work, we evaluated surface roughness of CMP pad to correlate the roughness with CMP performance such as material removal rate (MRR) and pad lifetime. Pad surface was analyzed by 3-dimensional profiler and scanning electron microscope (SEM). We found that MRR could be varied with the pad life time and roughness. We also found that suitable roughness range is exist to get stable CMP performance. Finally, we introduced ‘pre-conditioning’ method to manage the roughness of CMP pad to get stable CMP performance at the initial pad life time.
Effect of Sample Geometry and Placement on Iron Ore Processing by Microwave
Authors: Barani K. , Koleini S.M.J. , Rezai B. , Khodadadi A.
Published: March 2012

Sample and oven factors are important in determining the magnitude and uniformity of power absorption. The effects of these parameters on water and food materials have been studied. However, interaction of microwave with minerals is poorly understood. In this research, the effect of sample and oven parameters such as sample volume and placement of sample on microwave heating of water and an iron ore material were studied and obtained data were compared. The results showed that for water heating, with increasing in sample volume from 200 to 1000cm3 the microwave energy absorbed by water was increased from 71.27 to 100%, also with increasing in sample surface area from 50.24 to 78.50 cm2 the microwave, energy absorbed by water was increased from 76.36 to 89.09%. In iron ore heating, the surface area is effective parameters only. When iron ore sample volume was increased without increasing in surface area, the microwave absorption was constant while with increasing in sample surface area from 50.24 to 126.6 cm2, the microwave energy absorbed by iron ore was increased from 36.6 to 61.82%. The maximum temperature for iron ore material was occurred at 5.7 cm distance from the center while the maximum temperature for water sample was occurred at 5cm distance from the center
Modeling and Optimization of EDM of Al 7075/10wt% Al2O3 Metal Matrix Composites by Response Surface Method
Authors: Gopalakannan S. , Senthilvelan Thiyagarajan , Kani Kalaichelvan
Published: March 2012

The newly engineered metal matrix composite (MMC) of aluminium 7075 reinforced with 10 wt% of Al2O3 particles were prepared by stir casting method. Electrical discharge machining (EDM) was employed to machine MMC with copper electrode. The experiment plan adopts face centered central composite design of response surface methodology. Analysis of variance was applied to investigate the influence of process parameters and their interactions viz., pulse current, gap voltage, pulse on time and pulse off time on material removal rate (MRR), electrode wear ratio (EWR) and surface roughness (SR). The objective was to identify the significant process parameters that affect the output characteristics. Further a mathematical model has been formulated by applying response surface method in order to estimate the machining characteristics such as MRR, EWR and SR.
The Effect of Microstructural Changes Induced by Annealing on Mechanical Properties of FeCoCrMoCBY Bulk Glassy Alloy
Authors: Seifoddini Amir , Ahmadabadi Mahmoud Nili , Heshmati-Manesh Saeed , Stoica Mihai , Kuehn Uta , Eckert Jürgen
Published: March 2012

Bulk metallic glasses have interesting mechanical properties, such as high strength up to 5 GPa, high elastic strain and many other additional desirable properties. However, BMGs beyond the elastic region fail catastrophically on one dominant shear band and show little macroscopic plasticity in an apparently brittle manner. Nano-crystallized BMGs have been found to possess better ductility comparing with brittle parent BMGs. Annealing treatment of glassy alloys is a useful method to prepare bulk nano-crystalline alloys. In the present study, the crystallization trend of the FeCoCrMoCBY alloy which is claimed to have the best glass forming ability was studied in various times in temperature ranges of a) between Tg (glassy temp.) and Tx1 (first crystallization temp.), and b) between Tx1 and Tx2 (second crystallization temp.). The influences of different annealing time and temperatures on the microstructure and microhardness of Fe41Co7Cr15Mo14Y2C15B6 BMG are reported in this paper.
An Approach of Weighted Principal Component Analysis Based Taguchi Method for Parametric Optimization of Submerged Arc Welding
Authors: Barma J. Deb , Shil Mitul B. , Dan P.K. , Bandyopadhyay A.
Published: March 2012

Quality is the collection of features and characteristics of a product that contribute to its ability to meet given requirements. The quality of a weld joint is directly influenced by the welding parameters during the welding process. Often, a common problem that has been faced by the manufacturer is the control of the process parameters to obtain a good welded joint. Quality level is denoted as the probability of conformance and is a function of system variables and system specification. The present work is aimed to improve the quality of the weldment in SAW using Weighted Principal Component based Taguchi method. Three process parameters such as voltage, carriage speed and stand of distance are identified to carry out the study. Mechanical properties such as tensile strength and hardness are considered to be the response parameters in the present study.
Investigation on the Deformation Pattern and Energy Absorption Capacity of Hot-Stamping Structures with Partial Pressing Hardening
Authors: Zhuang Wei Min , Yu Wan Dong , Chen Yan Hong
Published: March 2012

Compared to traditional hot-stamping process, partial pressing hardening (PPH) can alter mechanical properties of metal components in any desired regions by controlling its bainite and martensite distribution. The mechanical property of the structure that is produced by PPH process is quite different from traditional hot-stamping steels (Martensitic steels) and has never been evaluated. Based on the merit of PPH process, this paper investigated the effect of bainite-martensite distribution on the deformation pattern and energy absorption capacity of PPH structures. The FE material models of martensitic and bainitic steel were set up and verified. After that, the deformation pattern and energy absorption capacity of PPH structures with different distribution patterns was investigated and discussed by three-point bending and tensile bending FE simulation.
Mathematical Modeling of Machining Parameters in Electrical Discharge Machining with Cu-B4C Composite Electrode
Authors: Anandakrishnan V. , Senthilkumar V.
Published: March 2012

Copper based metal matrix composite reinforced with Boron Carbide is a newly developed Electrical Discharge Machining (EDM) electrode showing better performance than the conventional copper based electrode. Right selection of machining parameters such as current, pulse on time and pulse off time is one of the most important aspects in EDM. In this paper an attempt has been made to develop mathematical models for relating the Material Removal Rate (MRR), Tool Removal Rate (TRR) and Surface roughness (Ra) to machining parameters (current, pulse-on time and pulse-off time). Furthermore, a study was carried out to analyze the effects of machining parameters on various performance parameters such as, MRR, TRR and Ra. The results of Analysis of Variance (ANOVA) indicate that the proposed mathematical models, can adequately describe the performance within the limits of the factors being studied. Response surface modeling is used to develop surface and contour graphs to analyze the effects of EDM input parameters on outer parameters.
A Study on Design of Communication Protocol for CPS Simulation
Authors: Kim Ji Yeon , Kim Hyung Jong , Kim Jin Myoung , Kim Won Tae
Published: March 2012

The term “cyber-physical system (CPS)” refers to a computing system that integrates physical processes and computational devices via a network. There are many physical and computational devices in a CPS, which can function automatically through inter-device interactions. Because a CPS is usually used for large-scale complex systems, to ensure reliable CPS operation, its design and execution should be verified through simulations. For CPS simulation, a communication protocol should be established for data transmission between physical systems and the corresponding simulation models during the simulation, including control algorithms for regulating differences between the two systems. First, because physical systems and simulation models are advanced in real time and logical time, respectively, time regulation methods should be included in the control algorithm. Second, to simulate various types of physical systems, a flexible simulation environment, independent of the operating environment such as the type of communication middleware, is required. In this paper, we propose a communication protocol for data transmission between physical systems and simulation models via a middle layer that contains the policies for handling the two different clocks of each system: virtual and real. The proposed communication protocol can be used not only for communication between the two systems but also for overcoming the problems caused by the differences in their operating environments. The contribution of this work is in that it defines a communication protocol and proposes methods for controlling different types of systems.
XML Representation of System Entity Structure for Distributed Modeling Simulation
Authors: Choi Dal Nim , Kim Jin Myoung , Kim Won Tae , Kim Hyung Jong
Published: March 2012

Distributed simulation refers to the execution of a complex model on geographically dispersed simulators, and it can increase the speed of a simulation and eventually decrease the simulation execution time. The distributed simulation enables models to be executed in physically distributed position. The system entity structure (SES) is used to represent the structural relation of simulation models and there are several SES’s XML representation methods. To make use of the SES in a distributed simulation environment, the revision of existing XML representation is needed. In this paper, we propose revised XML representation for loading models dynamically in the distributed simulation environment. A template of XML representation is defined to meet a number of modeling requirements, and it shows the specific information of model’s hierarchy and coupling. Each simulator’s model loader analyzes the XML-based SES representations and loads information of a model dynamically. We validate our method using a coupled model example.
A Study of Resource-Constrained Project Optimization with Discounted Weighted Earliness-Tardiness Penalty Costs
Authors: Khoshjahan Yazdan
Published: March 2012

This research consider a project scheduling problem with the object of minimizing weighted earliness-tardiness penalty costs, subject to precedence relations among the activities and resource-constrained. Project activities are assumed to have a known deterministic due date, a unit earliness as well as a unit tardiness penalty cost and constant renewable resource requirements. The objective is to schedule the activities in order to minimize the total weighted earliness–tardiness penalty cost of the project subject to the finish–start precedence constraints and the constant renewable resource availability constraints. With these features the problem becomes highly attractive in just-in-time environments. A genetic algorithm (GA) is proposed to solve this model. In addition design of experiments and response surface methodology are employed to tune the GA parameters and to evaluate the performance of the proposed method in 270 test problems. The results of the performance analysis will be shown at the end of this paper.
Edge Tracing Based on Improved Genetic Algorithm
Authors: Liu Bin Bing , Chen Hai Qing , Huang Chong , Yang Zhen Gang
Published: March 2012

In this paper, we proposed a new edge tracing method with high robustness to noise. Through representing edge with maximal gradient path encoded by chain code, the edge tracing problems can be converted into combinatorial optimization problems, and so they can be solved by genetic algorithm. We optimized the traditional genetic algorithm in order to improve the convergence rate. Our method is effective to edges with any shape because it does not require any prior knowledge about the edges. In this paper we also discussed the problem of edge winding and folding and expatiated how to avoid it by designing proper gene coding method and punishment function. Furthermore, by transforming the region of interests from Cartesian coordinates to polar coordinates before edge tracing, this method can be used for closed edges. The experimental results show this is an effective edge tracing method with high robustness and flexibility.
Effect of Addition of Nano Silica on Modulus of an Acrylic/Melamine Automotive Topcoat
Authors: Tahmassebi Nargess
Published: March 2012

In the present study, the influence of addition of various loads of hydrophobic nano silica on modulus of an acrylic melamine automotive topcoat was investigated. The results indicated that addition of hydrophobic nano silica to acrylic melamine decreased its Young’s modulus. The same behavior was observed for nano indentation modulus just at low nano silica content. This property was increased at high nano silica content. Poor interaction between nano particles / acrylic melamine and ball bearing effects of nano particles were used to explain decrease in modulus. Increase in nano indentation modulus was attributed to particle flocculation.
Effect of Nano-Silica Loading on Barrier and Mechanical Properties of Food Packaging Based LLDPE Film
Authors: Thanakkasaranee Sarinthip , Pradittham Arjaree , Atong Duangduen , Pechyen Chiravoot
Published: March 2012

In the present work, nano-silica was used in preparing LLDPE/nano-silica as an outer layer film for LLDPE reinforced nano-silica/LDPE/LLDPE multilayer film for microwavable packaging materials in future work. Thus, the objective of this work was studied the optimal of modified nano-silica loading into LLDPE film on barrier and mechanical properties. The experiments were divided into 2 main steps: surface treatment of nano-silica with vinyltriethoxysilane by ultrasonic agitation, and preparation of linear low density polyethylene film reinforced with untreated and treated nano-silica which different silica quantities are 1, 3, and 5 phr by blown film extruder. And then the surface morphology of films was examined by SEM. The properties of the film were analysis, oxygen transmission rate of film was characterized by OTR, water vapor transmission rate of film was characterized by WVTR, and tensile properties (tensile strength, % elongation and modulus) of films were examined by universal testing machine. Results indicated that the LLDPE loaded with 1 phr of nano-silica treated with vinyltriethoxysilane had better tensile strength and % elongation than at 3 and 5 phr of treated and untreated nano-silica.
Mechanical Properties of Montmorillonite-Filled Natural Rubbers Compatibilized by Epoxidized Natural Rubbers
Authors: Potiyaraj Pranut , Ngamsurat Sittiporn , Poklong Wasan
Published: March 2012

The effects of epoxidized natural rubber as a compatibilizer in modified-montmorillonite filled natural rubber were studied. Natural rubber was compounded with 2, 5 and 10 parts per hundred rubber (phr) of organomodified montmorillonite as a reinforcing filler and cured by using a conventional sulfuric system. Epoxidized natural rubber with 25 and 50 mol% epoxidic units (ENR25 and ENR50, respectively) was used as compatibilizer at the amount of 5, 10 and 15 phr. Rubber compounds were then tested for their curing properties. Test specimens for mechanical testing were prepared by compression molding. The use of montmorillonite as a filler in natural rubber efficiently improved mechanical properties that are tensile strength, modulus, elongation at break, tear strength and hardness, especially with the small amount of montmorillonite. This is supposed to be related to intercalation and exfoliation process. The increasing amount of montmorillonite caused the filler to be agglomerated thus the reinforcing efficiency was reduced and some mechanical properties were dropped. It was further founded that epoxidized natural rubber compatibilized montmorillonite filled natural rubber effectively. As the amount of epoxidized natural rubber increased, the mechanical properties tended to increase. The presence of epoxidized natural rubber improved filler-rubber interaction and filler dispersion. The compatibilizing efficiency of ENR25 was slightly superior to that of ENR50. This is because ENR 25 contains more double bonds than ENR 50 hence higher strain-induced crystallinity is occurred
Ultrafine Wollastonite Reinforced Polypropylene/Ethylene Propylene Diene Rubber Thermoplastic Elastomers
Authors: Chuayjuljit Saowaroj , Karnjanamayul Thatisorn
Published: March 2012

In this study, tensile properties, thermal stability and morphology of polypropylene/ethylene propylene diene rubber/wollastonite (PP/EPDM/wollastonite) thermoplastic elastomer composites were tested and evaluated as a function of their compositions in comparison with PP/EPDM blends and native PP. PP was melt mixed with two loadings of EPDM (20 and 30% (w/w)) and for the composites each of these with three loadings of wollastonite (10, 20 and 30 parts by weight per hundred of the PP/EPDM resin) on a twin screw extruder and then injection molded. Both PP/EPDM blends provided a higher elongation at break but a lower tensile strength and Young’s modulus as compared with those of the neat PP. However, the addition of wollastonite microparticles (particle size of 1200 mesh) into the blends increased the Young’s modulus in a dose-dependent manner with increasing wollastonite loadings, whilst the tensile strength and elongation at break were decreased. Moreover, the thermal stability was improved by the presence of either EPDM or wollastonite in the PP matrix.
Synthesis of Polyaniline by Pulsed Plasma Polymerization Using Theta-Pinch Device
Authors: Suwanprateep Sasikan , Mongkolnavin Rattachat , Pimpan Vimolvan
Published: March 2012

Polyaniline was synthesized by pulsed plasma polymerization using a theta-pinch device. The process was done using oxygen plasma at a voltage of 20 kV, a pressure of 2 Pa and a discharging current of 125 kA. The number of the plasma shots was varied from 10, 15, 20, 25, to 30 shots. This parameter significantly affected the chemical structures of the synthesized polyanilines as revealed by FTIR spectra. While all synthesized polyaniline exhibited the characteristic peaks of quinoid ring and benzenoid group, the peaks corresponding to the formation of oxygen containing groups was found when high numbers of plasma shots were employed. This also caused the difference in UV-VIS absorption of these polyanilines. The highest conductivity of polyaniline was obtained when 20 shots of oxygen plasma were used. At this condition, polyaniline had a semi-crystalline structure and the thermal decomposition temperature at 262oC.
Mechano-Chemical Synthesis of TiB2-Al2O3 Nano-Composite by Reaction between TiO2, B2O3 and Al
Authors: Rabiezadeh Amin , Ataie Abolghasem , Hadian Ali Mohammad
Published: March 2012

In this research a composite structure containing of a TiB2 matrix with dispersed Al2O3 particles was obtained via mechanical alloying of Al, TiO2 and B2O3 powder mixture. The mixture was milled for different lengths of time. Phase evolutions of the milled powder mixture were investigated. Powder particle characteristics were evaluated by XRD, SEM and TEM techniques. The XRD results reveal that the reaction begins during first 10 h milling by formation of TiB2 and Al2O3¬ phases and further milling causes partial amorphization of powder mixture. SEM micrograph of the sample milled for 30 h exhibited ultrafine particles of Al2O3-TiB2, but TEM images show that particles consist of some grains in the range of nano-size. The mean crystallite size of final product is about 25 nm.
Surface Modification of Aluminum Alloy Using Plasma Based Ion Implantation and Deposition
Authors: Wada Tadahiro , Nakanishi Jun , Miki Yasuhiro , Asano Makoto , Iwamoto Koji , Hanyu Hiroyuki
Published: March 2012

Aluminum alloys are used for mechanical parts, but the alloys have poor wear-resistance. To increase their wear resistance, a hard coating is applied to the surface of the alloys. Diamond-like carbon (DLC) is applied in surface modification technology due to its superior mechanical characteristics. In this study, in order to achieve effective surface modification to improve the wear resistance of the aluminum alloys, a new coatings-system was designed. This coating-substrate system is a multilayer coating-substrate system, which consists of nitriding pretreatment of the substrate, the intermediate layer of the silicon-based film and the outer layer of the DLC film. This new coating-system was used to deposit DLC film on three kinds of aluminum alloys that have different Si contents. In order to determine the influence of the Si contents on the mechanical properties of the DLC film, SEM observation of the cross section of the coating layer, the adhesion and the wear resistance of the layer were experimentally investigated. The results were as follows: (1) In the case of the DLC un-coated aluminum alloys, the rapid progress of the friction coefficient in the case of 10-N load was found at the short sliding distance. (2) The hardness of the DLC film was not decreased with the increase of Si contents. And the increase of Si contents did not have a negative influence upon the hardness of the DLC film. (3) The frictional coefficient of the Al-4%Si alloy was the smallest, the frictional coefficient of the DLC film was decreased with the increase of Si contents, and it was effective for improvement of the frictional coefficient to increase Si contents. The new coating-substrate system is effective for improving the adhesion between the substrate of the aluminum alloy and the DLC film. Moreover, the increase of Si contents was effective for the decrease in the frictional coefficient.
Low Temperature Solvolthermally Synthesized Nitrogen-Fluorine Doped TiO2 for Methyl Orange Photodegradation
Authors: Kwamman Tanagorn , Smith Siwaporn Meejoo
Published: March 2012

A low temperature solvothermal method was employed to synthesize nitrogen-fluorine doped TiO2 materials (N/F -TiO2) at various mole ratio of Ti:F; 10:1, 10:0.3 and 10:0.1, for photocatalytic applications. Doping fluorine and nitrogen in the TiO2 structure extend the spectra response of the materials toward a visible region resulting in the high efficiency to oxidize methyl orange (MO) under UV-Vis irradiation. The microstructure and photocatalytic activity of the materials appeared to depend on titanium precursors, titanium isopropoxide (TTIP) or tetrabutyl orthotitanate (TBOT), and the concentration of dopant (NH4F). The highest MO decolorization efficiency under UV-Vis irradiation for 30 minutes is about 86 % by using N-F-TiO2 (TTIP precursor) with Ti: F of 10: 3 as catalyst. The decolorization efficiencies of MO over N-F-TiO2 materials (TTIP precursor) are twice higher than that of the undoped catalyst.
Synthesis of Rice Straw Cellulose Ester for Use as Biodegradable Plastic Film
Authors: Ratanakamnuan Usarat , Ninsin Yan Yong
Published: March 2012

In this research, the feasibility to obtain cellulose film from rice straw was investigated. After delignification and bleaching of rice straw, the rice straw pulp was treated by acid hydrolysis in order to obtain rice straw cellulose powder. After that, the esterification of rice straw cellulose was carried out by using lauroyl chloride as an esterifying agent, toluene and pyridine as a solvent and a catalyst, respectively. The optimum condition for esterification was examined in terms of temperature and reaction time. Chemical structure and properties of modified cellulose such as morphology, thermal stability, and solubility were investigated. The rice straw cellulose ester film was prepared by casting method and the films obtained were tested for their tensile properties.