bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance and Emission Characteristics of Diesel Engine Running on Blended Palm Oil
Authors: Iqbal A.M. , Zainal Z.A. , Mazlan M. , Al Bakri Abdullah Mohd Mustafa , Salim M.S.
Published: September 2013

Rapid increasing of industrialization and motorization has led arising of petroleum and energy demand. This pursue a new energy blends to cater the depletion of fossil fuel and the environmental degradation condition. Malaysia is blessed, which has suitable climate to plant alternative fuel (palm oil) and become one of the largest exporters to the world. Palm oil in its refined form as cooking oil has high energy content which can be adopted as an alternative to the petroleum based fuel. This paper evaluates the performance and emission characteristics of refined palm oil (RPO) as a fuel to the diesel engine. Palm oil and its blends composition with 20%, 40%, 60% as well as pure palm oil (100%) and diesel were tested separately under various engine loads. Five series of tests data on each type of fuel were analyzed and compared. Moreover, by increasing the percentage of RPO in blends would lead a character of higher percentage in density and viscosity. Studied revealed that the small percentage of RPO composition promises a good thermal efficiency together with the emission released.
The Effect of Rotational Speed on Flow Behavior and Weld Properties in Friction Stir Welding of Pure Aluminum
Authors: Dawood Hasan I. , Mohammed Kahtan S. , Wahab Zurida A.
Published: September 2013

Friction stir welding is a solid state green welding technique. Its key benefit is to allow welding of aluminum that cannot be readily done by fusion arc welding. In this study, two pure aluminum strips of 2mm thick were friction stir welded together. For all welding pairs, three rotational speeds of 1000, 1500 and 2000 rpm were used. The traverse speed, axial force and tool geometry were kept constant. Parameters optimization based on the results of the micrographic, macrographic, microhardness and tensile strength, indicated that sound joints with the best mechanical and microstructural properties can be obtained at rotational speed of 1500 rpm and welding transverse speed of 60 mm/min. Microscopic examination and local mechanical properties analysis suggested that mechanical mixing is the major material flow mechanism in the formation of the nugget stirred zone.
Influence of Current Density on Porous Silicon Characteristics
Authors: Husnen R. Abd , Naser Mahmoud Ahmed , Al-Douri Y. , Hashim U.
Published: September 2013

Porous silicon structures have been fabricated by electrochemical etching using different current density. From field emission scanning electron microscope images (FE-SEM) it was observed that more uniform distribution of pores is obtained when the current density was increased from 20mA/cm2 to30 mA/cm2. The porosity is estimated based on the analysis of FE-SEM and gravimetric analysis, the results were confirmed by reflectivity measurements which show that the high current density and porous samples have low reflection for wide spectrum. Results show good improvement in the solar cell efficiency.
Synthesis and Characterization of Electroless Copper Coated SiC Particles
Authors: Azmi K. , Mohd Salleh M.A.A. , Derman M.N.
Published: September 2013

Silicon carbide reinforced copper matrix (Cu-SiCp) composites fabricated via the conventional powder metallurgy methods have inferior thermophysical properties due to the weak bonding between the copper matrix and the SiCp reinforcement. In order to improve the bonding between the two constituents, the SiCp were copper coated via electroless coating process. Based on the experimental results and findings, a continuous copper deposition on the SiCp was obtained via the electroless plating process. The copper film was found to be high in purity and homogeneously deposited on the SiCp surfaces. The thickness of the coated copper layer was roughly estimated to be around 1μm.
Preparation of Cyclopentyl Trisilanol Silsesquioxanes - Modified Natural Rubber (CpSSQ(OH)3 ENR-50) Composite Hybrid in the Presence of HCL Acid
Authors: Hamzah Rosniza , Bakar Mohamad Abu , Zulkepli Nik Noriman , Mohd Salleh Mohd Arif Anuar , Al Bakri Abdullah Mohd Mustafa
Published: September 2013

A composite comprising cyclopentyl trisilanol silsesquioxanes (CpSSQ(OH)3) and 50% epoxidized natural rubber (ENR-50) was prepared at reflux temperature employed hydrochloric acid (HCl) as catalyst. HCl was found to be an effective catalyst to promote ring opening reaction of ENR-50 and tailored CpSSQ(OH)3 to the ENR-50 polymer chains via chemical reaction. FTIR spectroscopy reveals a hydroxyl stretching indicating the occurrence of epoxide ring opening reaction. 1H NMR analysis further proved the incorporation of CpSSQ(OH)3 into ENR-50 polymer chains via shiftment of proton chemical shift and addition in the proton integrals. Si 29NMR analysis evidence the Si-O-C bond through a chemical shift of silanol group from CpSSQ(OH)3.
Memristive Behavior of TiO2 Nanostructures Grown at Different Substrate Positioning by Immersion Method
Authors: Kamarozaman Nur Syahirah , Asiah Mohd Nor , Aznilinda Z. , Bakar R.A. , Abdullah W.F.H. , Herman S.H. , Rusop M.
Published: September 2013

In this paper, the physical characteristics and memristive behavior of TiO2 nanostructures grown at different substrate positioning by wet chemical solution were investigated. TiO2 thin film as a seed layer for TiO2 nanostructures growth was first deposited on ITO-coated substrate by RF magnetron sputtering method. TiO2 nanostructures were then grown by immersing the TiO2 thin film/ITO/glass sample in 10M NaOH solution at 80 °C while studying the effect of the substrate position to the nanostructure growth and thus its memristive behavior. Characterization on the growth morphology of TiO2 nanostructures was observed using scanning electron microscopy (FESEM). The current-voltage (I-V) measurement of the device was investigated for its memristive behavior. Different growth morphology of TiO2 nanostructures was observed at different substrate positioning. It was found that sample immersed with TiO2 layer facing down the vessel result in the formation of TiO2 nanowires and exhibit better memristive behavior.
Effects of Calcium Carbonate on Melt Flow and Mechanical Properties of Rice Husk/HDPE and Kenaf/HDPE Hybrid Composites
Authors: Noor Zuhaira Abd Aziz , Rahmah Mohamed
Published: September 2013

In this research, calcium carbonate (CaCO3) was compounded with rice husk/high density polyethylene (HDPE) and kenaf/HDPE composite at different filler loadings to produce hybrid composites. Melt flow index (MFI) and mechanical properties of hybrid composite was investigated. From the test results, the addition of CaCO3 filler had decreased melt flow index (MFI) on both composites. In terms of mechanical properties, tensile strength, elongation at break and impact strength decreased, whereas Youngs Modulus increased with the increase of CaCO3 in both kenaf/HDPE and rice husk/HDPE composites. Impact strength of unfilled rice husk/HDPE composite was lower than unfilled kenaf/HDPE composite, however impact strength of CaCO3/rice husk/HDPE hybrid composite were found to have slightly higher than CaCO3/kenaf/HDPE hybrid composite with addition of 10% and 20% of CaCO3.
Long Physico-Chemical and Biological Monitoring for Treated Artificial Tidal Flats with Recycled Paper Sludge in Ago Bay, Japan
Authors: Dabwan Ahmed H.A. , Imai Daizo , Kaneco Satoshi , Katsumata Hideyuki , Suzuki Tohru , Ohta Kiyohisa
Published: September 2013

Treated dredged sediment by using Hi Biah System (HBS) was used for the construction of five different artificial tidal flats (E1-E5) in Ago Bay, Japan. AGOCLEAN-P which is mainly made from paper sludge ashes was used as a coagulant and hardener. After the construction, continuous monitoring for the physico-chemical and biological parameters was carried out quarterly for 28 months from May 2005 to August 2007. Physico-chemical parameters measured were; particle size, loss on ignition (LOI), total organic carbon (TOC), chemical oxygen demand (COD), water content (WC), chlorophyll a, and acid volatile sulphide (AVS). At the end of the experiment, physico-chemical parameters for the artificial tidal flats along with the sandy natural flat (S2) were almost similar. In regards to the natural muddy flats (S1) the results showed remarkable increase in the particle size <0.75 μm throughout the experimental period, whereas insignificant decrease was observed for the medium particle size. In addition the area around station (S1) was characterized by high concentration of silt/clay around 75% for the particle size less than 75μm. Biological parameter was represented by macrobenthos abundant as number of individuals, biomass, and species number. The abundant macrobenthos during the first year of monitoring was mollusca followed by polychaeta then bivalve, however at the end of the experiment, bivalve was the most dominant macrobenthos followed by mollusca and then polychaeta indicating that healthy environment was created.
Analysis of Stress and Strain in ZnO Nanoparticle-Bi2O3-Mn2O3 Varistor Ceramics at Different Annealing Temperatures
Authors: Sendi Rabab Khalid , Mahmud Shahrom
Published: September 2013

The stress and lattice constants in zinc oxide (ZnO) nanoparticles play a major role in determining the distortions that occur in the crystal during the preparation of the sample as a result of exposure to several factors, such as external strain, temperature, pressing, and structural defects (oxygen vacancies and zinc/oxygen interstitials). 20 nm zinc oxide nanoparticles were used to make high-density ZnO discs doped with Bi2O3 and Mn2O3 via uniaxial pressing at 4 ton/cm2 and sintering at 1200 °C for 1 h. Structural, elemental, and optical characterizations were then performed on the samples using various techniques. High-oxygen thermal annealing significantly affected the varistor, particularly in enhancing the growth of the grain even at a low annealing temperature (400 °C). The strong solid-state reaction during annealing may be attributed to the high surface area of the 20 nm ZnO nanoparticles that exhibited a strong surface reaction even at low annealing temperatures. The annealing treatment also improved the grain crystallinity, as shown by the transition of the intrinsic compressive stress to tensile stress based on the XRD lattice constant and full-width at half-maximum data. Therefore, high-oxygen thermal annealing can be used as a new technique in controlling the stress in ZnO nanoparticle-Bi2O3-Mn2O3 based varistors with improved structural and optical properties.
Relationship between Compressive, Splitting Tensile and Flexural Strength of Concrete Containing Granulated Waste Polyethylene Terephthalate (PET) Bottles as Fine Aggregate
Authors: Juki Mohd Irwan , Awang Mazni , Annas Mahamad Mohd Khairil , Boon Koh Heng , Othman Norzila , binti Abdul Kadir Aeslina , Roslan Muhammad Asyraf , Khalid Faisal Sheikh
Published: September 2013

This paper describes the experimental investigation of relationship between splitting tensile strength and flexural strength with the compressive strength of concrete containing waste PET as fine aggregates replacement. Waste PET was reprocesses and used as the artificial fine aggregate at the replacement volume of 25%, 50% and 75%, Cylindrical and prism specimens were tested to obtain the compressive, splitting tensile and flexural strength at the age of 28 days. Based on the investigation, a relationship for the prediction of splitting tensile and flexural strength was derived from the compressive strength of concrete containing waste PET as fine agglegate replacement.
Electrical Properties Dependence on Substrate Temperature of Sputtered ZnO Nanoparticles Thin Films on Teflon Substrates
Authors: Muhamad Sauki Nur Sa’adah , Herman Sukreen Hana , Ani Mohd Hanafi , Rusop Mohamad
Published: September 2013

Zinc oxide (ZnO) thin films were deposited on teflon substrates by RF magnetron sputtering at different substrate temperature. The effect of substrate temperature on ZnO thin films electrical and structural properties were examined using current-voltage (I-V) measurement, and x-ray diffraction (XRD) It was found that the electrical conductivity and resistivity of the ZnO thin film deposited at 40°C was the highest and lowest intensity accordingly. This was supported by the crystalline quality of the films from the x-ray diffraction (XRD) results. The XRD pattern showed that the ZnO thin film deposited at 40°C has the highest intensity with the narrowest full-width-at-half-maximum indicating that the film has the highest quality compared to other thin film.
Numerical Simulation of Microfluidic Separators
Authors: Ariffin Shahrul A.B. , Hashim U. , Adam Tijjani
Published: September 2013

Microfluidic devices present a powerful platform for working with living cells and even gases. Parameter such as the length and volume scales of these devices in miniaturize system makes it possible to develops and perform detailed analyses with several advantages. The objective of this project is to do a design of 1μm microfluidic separator device that consist the microchannel. Furthermore, another objective is to understand the fundamental physical processes of fluid flow in these devices and to predict their behavior and every method using in the simulation of COMSOL Multiphysics 3.5 software will be elaborate in numerical simulation technique section. Finally, result from the simulation such as concentration, fluidic flow pressure and velocity field will be observed and explained in the result section.
Determination of Interlayer Mixing and Oxygen Non-Stoichiometry in LiNi0.8Mn0.1Co0.1O2-δ Using Powder Diffraction Data
Authors: Idris Mohd Sobri , Osman Rozana A.M.
Published: September 2013

The effect of preparation conditions, temperature and atmosphere, on oxygen stoichiometry and interlayer cation mixing in the layered rock salt material LiNi0.8Mn0.1Co0.1O2-δ has been investigated using X-Ray powder diffraction, including Rietveld refinement. Interlayer mixing occurs as a direct consequence of oxygen deficiency; samples with least oxygen deficiency and most cation order were obtained on firing in O2 at ~ 900 950C.
Structure Refinement Strategy of Li-Based Complex Oxides Using GSAS-EXPGUI Software Package
Authors: Idris Mohd Sobri , Osman Rozana A.M.
Published: September 2013

This paper discussed refinement strategy that been used to reveal crystallographic properties of lithium-based complex oxides with layered rock salt structure. Rietveld analysis using XRD data was used to determine the amount of interlayer mixing and estimate oxygen contents. The structural model and refinement methodology was controlled and validated initially using a standard sample. Thus, this paper summarized structure refinement strategy that been used to quantify the degree of cation order associated with interlayer mixing and investigate the sensitivity of laboratory XRD data to oxygen non-stoichiometry that recently published elsewhere [.
Joining of Dissimilar 6063 Aluminium Alloy – 316L Stainless Steel by Spot Welding: Tensile Shear Strength and Heat Treatment
Authors: Mohd Noor Mazlee , Zhen Alvin Tan Yin , Jamaludin Shamsul Baharin , Hayazi Nur Farhana , Shamsudin Shaiful Rizam
Published: September 2013

Tensile shear strength and ageing treatment of dissimilar 6063 aluminum alloy-316L stainless steel joint fabricated by spot welding were investigated. The results showed that tensile shear strength increased with the increasing of welding current. The enhancement of tensile shear strength of the joints was due to the enlargement of the nugget diameter. It was also found that the tensile shear strength values for heat treated joint almost similar to that of non-heat treated joint.
Electrochemical Corrosion Behaviour of Mg-(Ca,Mn) Sacrificial Anodes
Authors: Shamsudin Shaiful Rizam , Rahmat Azmi , Isa Mahdi Che , Derman Mohd Nazree , Daud Abdul Razak
Published: September 2013

The aim of the study is to identify the effect of Ca in Mg-Mn alloy on electrochemical corrosion behavior for the development of high performance sacrificial anode. Mg alloys were fabricated by casting technique under an inert atmosphere. 0.35 ~ 1.11 wt.% of Ca were added as alloying element. The finding shows that the addition of small Ca in Mg-Mn anodes was found not significantly affecting the corrosion rate. However, small content of Ca was as much as necessary improving electronegativity of open circuit potential and modifying anodic polarization in promoting the instabilities of surface passive layer hence results in the further dissolution process between ion and alloy species underneath. No passivation occurs on the standard samples. Pitting profile only occur on Mg-Mn anode that has lower Ca content (0.35 wt. %). An XRD result shows no present of Mg2Ca phase on the as-cast anode containing 1.11 wt. % Ca. As a conclusion, the influence of small content of Ca was profoundly modifying electrochemically behaviour of Mg containing Mn anodes except corrosion rate.
Effect of Heat Treatment on Ni-P-Cg(Graphite)-SiC Composite Coated Cast AlSi Alloy
Authors: Mohtar M.M. , Ripin Z.M. , Ahmad Z.A.
Published: September 2013

The study presents the effect of heat treatment on electroless N-P-Cg-SiC composite coated cast AlSi (ADC12) alloy. No significant changes are noted on the average surface roughness and surface morphology of the coating film with different heat treatment processes. The growth of the hard Ni3P phase in the electroless Ni-P-Cg-SiC composite coating after heat treatment at 400°C for one hour strongly enhance the micro hardness of the AlSi-alloy (ADC12) surface from originally 101HV to 689HV. However, the micro hardness of the cast AlSi-alloy substrate decreases form 100HV to 60HV.
Mathematical Model of Elastic Crack Interaction and Two-Dimensional Finite Element Analysis Based on Griffith Energy Release Rate
Authors: Daud Ruslizam , Ariffin Ahmad Kamal , Abdullah S. , Majid M.S. Abdul , Rojan M.A.
Published: September 2013

Stress shielding interaction effect of two parallel edge cracks in finite body under uniaxial loading is analysed using developed finite element (FE) analysis program. In present study, the stress shielding interaction is formulated as a mathematical model called stress shielding damage (SSD) model. SSD model used to define the combination and re-characterization of crack interaction from multiple cracks to single crack. Focus is given to weak crack interaction state as the crack interval exceed the length of cracks (b > a). The crack interaction factors are evaluated based on Griffith strain energy release rate and mode I SIF using J-integral analysis. For validation, the stress shielding factor parameters are compared to single edge crack SIF as a state of zero interaction in a form of crack unification limit (CUL) and crack interaction limit (CIL).
Effects of Fly Ash Addition on Compressive Strength and Flexural Strength of Foamed Cement Composites
Authors: Wahab Roshasmawi Abdul , Mohd Noor Mazlee , Jamaludin Shamsul Baharin , Ismail Khairul Nizar
Published: September 2013

In this study, the mixing of polystyrene (PS) beads and fly ash as a sand replacement material in foamed cement composites (FCC) has been investigated. Specifically, the mechanical properties such as compressive strength and flexural strength were measured. Different proportions of fly ash were added in cement composites to replace the sand proportion at 3 wt. %, 6 wt. %, 9 wt. % and 12 wt. % respectively. The water to cement ratio was fixed at 0.65 meanwhile ratios of PS beads used was 0.25 volume percent of samples as a foaming agent. All samples at different mixed were cured at 7 and 28 days respectively. Based on the results of compressive strength, it was found that the compressive strength was increased with the increasing addition of fly ash. Meanwhile, flexural strength was decreased with the increasing addition of fly ash up to 9 wt. %. The foamed cement composites with 12 wt. % of fly ash produced the highest strength of compressive strength meanwhile 3 wt. % of fly ash produced the highest strength of flexural strength.
Development of Nanocement Mortar as a Construction Material
Authors: Al-Rifaie Wail N. , Mahdi Omar Mohanad , Ahmed Waleed Khalil
Published: September 2013

The present research examined the compressive and flexural strength of nanocement mortar by using micro cement, micro sand, nanosilica and nanoclay in developing a nanocement mortar which can lead to improvements in ferrocement construction. The measured results demonstrate the increase in compressive and flexural strength of mortars at early stages of hardening. In addition, the influence of heating on compressive strength of cement mortar. General expressions to predict the compressive strength, modulus of rupture for the developed nanocement mortar in the present work are proposed.
Extraction of Silica from Palm Ash Using Citric Acid Leaching Treatment: Preliminary Result
Authors: Pa Faizul Che , Abdullah C. , Fazlul B.
Published: September 2013

Large quantities of agricultural wastes such as palm ash and rice husk are found throughout Malaysia, have a possibility to be used as a usefully renewable source for production of energy and silica (SiO2). Extensive researches have been carried out to extract silica from agricultural wastes such as rice husk, due to silica as a useful raw material for industrial application. In the previous studies, the strong acid leaching treatment was carried out to remove metallic impurities and organics contained in rice husk. Since leaching treatment is a proper route to extract the silica, sulphuric acid (H2SO4), hydrochloric acid (HCl) and nitric acid (HNO3) solutions are currently used in leaching treatment to prepare silica materials [. A strong acid leaching treatment, however, is significantly hazardous to the environment and people. In this study, the weaker acid, citric acid solutions were used to replace strong acid in leaching processes. Preliminary results showed that silica can be extracted from palm ash using citric acid leaching treatment under the optimum extracting conditions with 70°C of solution temperature, 60 minutes of reaction time and concentration of citric acid of more than 2%. The purity of silica extracted is more than 90%.
Study on Synthesis of Polypyrrole via Chemical Polymerization Method
Authors: Bahraeian Sobhan , Abron Khatereh , Pourjafarian Fatemeh , Majid Rohah A.
Published: September 2013

Conductive polypyrrole (PPy) was synthesized using a chemical polymerization method in aqueous solution. A series of reactions were carried out with different reaction times of 240 mins and 20 mins. All results were compared to find the highest conductivity and yield. The formation of PPy was verified with Fourier transform infrared (FTIR) analysis which has detected the C-N and pyrrole stretching peaks at 1462 cm-1 and 1169 cm-1, respectively, while the x-ray diffraction (XRD) study has shown a broad halo pattern around 25 ̊ related to PPy. The PPy particles sizes of 5-20 microns were measured from the scanning electron microscope (SEM) image. It was found that in the presence of sodium dodecylbenzene sulfonate (DBSNa) as surfactant, the highest conductivity value of 3.18 S/cm and yield of 68% were achieved at 20 mins reaction time and temperature of 0 °C.
The Atomic Force Microscope Study of Self-Assembled Silicon Nanodots Growth Using Magnetron Sputtering System
Authors: Aldaw Idrees Fatima , Sakrani Samsudi , Othaman Zulkafli
Published: September 2013

In this paper self-assembled silicon nanodots have been grown on silicon substrate using radio-frequency magnetron sputtering system. This system were settled at varying experimental conditions such as substrate temperature, time of deposition, RF power and fixed argon flow rate. Then the surface roughness was measured by AFM which resulted average dots size of 113 nm. However, the presence of a small amount of grain atoms formed on the surface was confirmed using SEM measurement. The crystalline Si-NDs with (100) plane contributed sharp diffraction peak located at 69.5° was confirmed using XRD measurement. These results of Si-NDs structural properties support the possible growth technique of radio-frequency magnetron sputtering.
Effect of Rice Husk on Fired Ceramic Shell Strength
Authors: Harun Zawati , Kamarudin N.H. , Taib H. Mohd
Published: September 2013

In recent years, ceramic shell mould for investment casting process is often associated to defects due to its brittle properties. The defects would originate from cracking mechanism yielded from the ceramic brittleness. In this work, the improvement of ceramic shell mould by reinforcement technique was studied and analyzed. Rice husk consisting high percentage of silica content with the ability to withstand high temperature during casting process was studied as the reinforcing component as to impede cracking mechanism. Higher Modulus of Rupture (MOR) value of ceramic shell reinforced by rice husk fiber as compared to the non-reinforced ceramic shell MOR value was obtained. Nonetheless, presence of the fused silica phase from rice husk fiber was also found to lead the formation of a new phase of zircon (ZrSiO4). These two factors were found to influence the ceramic shell composition and indirectly enhanced the ceramic shell strength performance.
Impact of Controlled Hydrophobicity of the Organically Modified Silicates on the Properties of Biomedical Thermoplastic Polyurethane (TPU) Nanocomposites
Authors: Osman Azlin Fazlina , Halley Peter , Martin Darren
Published: September 2013

The impact of nanofiller surface modifications and hydrophobicity on the morphology and mechanical properties of the biomedical TPU nanocomposites was studied. We show that incorporating nanofillers with higher hydrophobicity promotes better dispersion of nanofiller in TPU matrix due to greater interaction between the nanofiller and the hydrophobic PDMS soft segment in this ElastEon TPU system. The nanocomposite with the most hydrophobic surface modification demonstrates the best nanofiller dispersion and intercalation and hence resulted in an overall best mechanical and thermomechanical properties when incorporated in 2 wt%. These findings show that the polarity matching between the TPU and the nanofiller determines the nanofiller-TPU interactions and thus the mechanical properties of the produced nanocomposites.
Sand Replacement Materials (SRM) in Sustainable Cement Composites; A Concise Review
Authors: Mohamad Madzura , Mohd Noor Mazlee , Jamaludin Shamsul Baharin
Published: September 2013

This paper presents a short review of research works on the development of sustainable cementitious matrix composites with addition of potential mineral wastes as sand replacement materials. The study emphasizes on the possibility of recycling and sustain the mineral wastes from natural and industrial by-products in order to reduce the consumption of natural resources, energy and cost, and at the same time to reduce the environmental pollution. The aim of this review is to share the ideas and present the findings from previous works undertaken to evaluate the suitability of mineral wastes as a sand replacement materials to produce sustainable and durable construction materials in the future.
The Numerical Simulation for High Temperature Creep of the Porous Cu Alloy
Authors: Chen Jian , Huang Zi Han , Li Wei , Ren Yan Jie , He Zhuo , Qiu Wei , He Jian Jun , Chen Jian Lin
Published: September 2013

In this research, the compression deformation were investigated under different elevated temperatures and strain rates, in order to obtain the creep constitutive equation. The effects of aperture load and pore shape on the compression properties of porous Cu alloys were studied by simulating the creep compression deformation at elevated temperature in ANSYS software. Pore size, pore shape and load are the main factors on the high temperature compression creep properties in porous Cu alloys. Samples with larger pore size, higher load and temperature showed inferior compression creep resistance such as bigger creep deformation, faster creep rates, and more unstable creep deformation. Stress concentrations generating around the edge in the wall of the pore were observed. Otherwise, the shape of pore has a severe influence on the structure properties of the material, i.e. every increase of pore edge corresponds to a decrease of stability in structure.
The Study of Composition and Morphology of Pd-Ag Alloy Powders by Pulse Electrodeposition
Authors: Chu Chin Ming , Yang Hsi Wen , Tsai Shen Li , Yang Wen Bing , Fang Teh Chen
Published: September 2013

Pd-Ag alloy powders were prepared on the stainless steel by pulse electrodeposition. Cyclic voltammetry found the reduction potential of Pd, Ag and Pd-Ag. The composition and morphology of Pd-Ag were investigated by means of SEM, EDS.
Effects of Boriding on Cavitation Erosion Resistance of Ti6Al4V Alloy
Authors: Shi Ye Ting , Cui Zhen Duo , Yuan Xu Bo , Yang Xian Jin
Published: September 2013

A pack boriding technique was employed to obtain a hard coating on the surface of Ti6Al4V alloy in this paper. The microstructure, surface appearance, hardness depth profile and the cavitation erosion behavior of the borided samples in 3.5% NaCl solution were examined. The cavitation erosion resistance of the borided samples was significantly improved as compared with the untreated samples. Increasing in the surface hardness and the compact boride layer contribute to the significantly enhanced cavitation erosion performance of Ti6Al4V alloy.
Development and Challenge of the Vehicle and Highway Bridges Dynamic Interaction
Authors: Liu Jia Feng , Li Yan
Published: September 2013

With the development of long-span flexible bridges and the increase of highway transportation, both the dynamic responses of highway bridges under high-speed and heavy vehicles and the safety control of vehicles have deserved general concerns. First, this paper briefly discussed some researches on coupling vibration of vehicle and highway-bridges, then roundly summarized main research achievements accounting on the vehicle analytical model, bridge analytical model, surface roughness of road, numerical method of vehicle-bridge coupling vibration and some other aspects. Meanwhile, some research trends and challenge on vehicle and bridge dynamic interaction in engineering application were pointed out.
Performance Evaluation of a Damaged Bridge by Using the Method Based on Dynamical Characteristic
Authors: Yuan Jie , Tang Xu , Liu Yang
Published: September 2013

The bridge inspection based on dynamical characteristics is the main technique for evaluating and diagnosing the performance of bridges, especially, for the situation that the bridge inspection based on static performance cannot be carried out. This study investigated the application of dynamical inspection to a bridge with accident during the construction. The dynamical performance of the damaged girders and piers were measured and compared with the healthy ones which have the same structural form in order to assess the performance of damaged bridge, and some treatment suggestions were proposed by account for the results obtained by visual inspection and crack observation.
Reliability Analysis of Two-Dimensional Series Portal-Framed Bridge System Based on Mixed Copula Functions
Authors: Liu Yue Fei , Lu Da Gang
Published: September 2013

In this paper, several commonly-used Elliptical copulas and Archimedean copulas were introduced, and their application in the correlation analysis were also described in detal. For the two failure modes of two-dimensional series portal-framed bridge system, the performance function values with respect to the failure modes were considered as the analysis variables of the chosen copula functions, and the Baysian copula selection method was applied to select the proper copula functions. And then, the two-dimension mixed copula function was built. Thereinto, the uncertain parameters of copula function were determined with Monte Carlo Sampling (MCS) method, so the numerical modeling of the mixed copula fuction about the failure mode of two-dimensional series portal-framed bridge system was achieved. Finally the reliability of this system was analyzed with the built mixed copula function, and the structural system failure probability was obtained.
Corrosion Resistance of Plasma Sprayed AT13 Composite Ceramic Coating on Mg
Authors: Lu Er Lin , Chen Yan , Lu Sheng
Published: September 2013

NiCoCrAlY/AT13 composite coating was prepared by plasma spraying technology on AZ91D substrate and sealed with three different methods. The corrosion resistances of the composite ceramic coatings with and without sealing were evaluated by immersion and electrochemical tests The results show that NiCoCrAlY/AT13 composite ceramic coating represents better corrosion property than single AT13 ceramic coating. The corrosion resistances of NiCoCrAlY/AT13 composite coatings with sealing are superior to that of unsealing coating. Among three sealed coatings, both coatings sealed with paraffin and varnish exhibit better corrosion resistance with corrosion rate of 0.130 g/(m2·h), 0.204 g/(m2·h), and Icorrof 1.754E-7 (A·cm-2), 9.493E-8 (A·cm-2) respectively, while the coating with epoxy resin sealing is relatively the worst one with corrosion rate of 0.744 g/(m2·h) and Icorrof 1.650E-7 (A·cm-2).
Study on Physical and Mechanical Properties of Cu/MoS2 Composites
Authors: Ma Dou Qin , Xie Jing Pei , Li Ji Wen , Wang Ai Qin , Wang Wen Yan , Cui Li Ke , Zhang Yin Di
Published: September 2013

Cu-3wt. %MoS2-7wt. %Mo and Cu-3wt. %MoS2 composites were prepared by repressing, re-sintering and vacuum hot pressing, respectively. Microstructures were characterized by optical metallographic microscope, EDS, SEM and X-ray diffraction analysis, respectively. The micro hardness, electric conductivity and density of samples were separately measured as well. Results show that the micro hardness of Cu-3wt. % MoS2-7wt. % Mo composites is about 33.3% higher than that of Cu-3wt. %MoS2 composites. The increase in micro hardness is attributed to the presence of Mo. The electric conductivity of Cu-3wt. %MoS2 and Cu-3wt. %MoS2-7wt. % Mo prepared by vacuum hot pressing were 80.6 % and 63.8% IACS, respectively, which is an increase compared with values of 80.2 % and 57.3% IACS of samples obtained by repressing and re-sintering.
Preparation and Microstructure of Nano ZrB2 Reinforced Aluminum Matrix Composites
Authors: Wang Hong Ming , Li Guirong , Cai Yun , Zhao Yu Tao
Published: September 2013

The ZrB2 particulate reinforced aluminum matrix composites were fabricated via melt direct reaction method using Al-K2ZrF6-KBF4 components. 850°C and 30 min were the optimized synthesizing temperature and reaction time separately. The metallurgical thermodynamic and kinetic processes were then analyzed in detail. It reveals that the interphases include Al3Zr, AlB2, [Z and [ atoms. The ZrB2 particulates can be acquired through the molecular combination between Al3Zr and AlB2 or atomic combination between Zr and B atomics. The in situ reaction between reactive salts and molten aluminum takes place spontaneously, which exhibits the character of liquid-liquid reaction. Scanning electronic microscope observation results demonstrate that the sizes of ZrB2 particulates are almost 100-200 nm. The intervals between particles are almost 200-400 nm, demonstrating a unirom status of distribution.
Numerical Analysis on the Cure-Induced Deformation of Fiber Composite Laminates
Authors: Li Pan , Jia Yu Xi
Published: September 2013

During the cure process of fiber reinforced resin matrix composites, the residual stress and deformation can be generated. The cure-dependent elastic model, which is the earliest constructed and the simplified form of the viscoelastic model, is most universally applied to the finite element analysis on the cure-induced deformation. However, stress relaxation and creep are the unique properties of resin matrix composites, which can affect the residual stress and deformation in some degrees. In this study, both the elastic model and the viscoelastic model were used to predict the residual stress and deformation of fiber composite laminates by means of the finite element method, and then a comparison between them was made. The results show that the difference between them decreases with the increase of fiber volume fraction or the decrease of resin curing shrinkage.
Porous LaFeO3 with High Response to Acetone Synthesized from Biotemplates
Authors: Ma Yu Zhen , Song Peng , Wang Qi
Published: September 2013

Biomorphic porous LaFeO3 samples were prepared using aspen leaves as biotemplates. The structural and microscopy characterization has been carried out with X-ray diffraction, scanning electron microscopy and transmission electron microscopy. XRD patterns confirm thatLaFeO3 shows perovskite phase with orthorhombic structure. The results of SEM and TEM revealed that the the obtained LaFeO3 with hollow and porous structure. And the porous LaFeO3 is composed of spherical particles with the size of 50-80 nm The gas sensing performance of as-prepared LaFeO3 nanocrystlas was investigated. It is found that porous LaFeO3 calcined at 700°C exhibit good sensitivity to acetone with rapid response.
Synthesis and Characterization of g-C3N4/α-Fe2O3 Composites with Enhanced Photocatalytic Activity
Authors: Huang Li Ying , Zhang Rong Xian , Sun Xiu Juan , Cheng Xiao Nong
Published: September 2013

A novel composite photocatalyst g-C3N4/α-Fe2O3 was prepared through calcination method. The photocatalysts were characterized by thermogravimetric analysis (TG), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The obtained g-C3N4/α-Fe2O3 composites show high efficiency for the degradation of Rhodamine B (RHB). The optimum photocatalytic activity of g-C3N4/Fe2O3 at a g-C3N4 content of 8.6% under visible light irradiation is almost 4.8 times as high as that of pure α-Fe2O3. The enhancement in visible light photoactivity of g-C3N4/α-Fe2O3 composites was attributed to the introduction of g-C3N4 and the interaction between g-C3N4 and α-Fe2O3.
Friction/Wear Properties of Ta-Doped TiO2 Films on Surface of Nano-Grained 316L
Authors: Shao Hong Hong , Jiang Xiu Ying , Peng Yu Ting , Chen Cheng , Zhai Rui
Published: September 2013

Ta-doped TiO2 films were deposited on surface of nano-grained 316L stainless steel by RF magnetron sputtering technology at room temperature. The surface morphology and friction/ wear properties of TiO2 films with different Ta-doped content were investigated. The results showed that the proper amount of Ta-doped could refine TiO2 film particles. The 23% Ta-TiO2 film on the surface of SNG-316L possessed the lowest friction coefficient (0.147), the best wear-resisting performance and the best friction performance.
Synthesis and DNA Binding Studies of Platinum (II) Complexes Based on Cyclodextrin
Authors: Tang Si Ping , Feng Yong Lan , Xu Zhi Feng , Wang De Ping
Published: September 2013

Mono-modified β-cyclodextrins ligands, L1 (6-mono-(N-aminoethyl) amino-β-cyclodextrin) and L2 (6-mono-(N-(pyridin-2-yl) ethylamino)-β-cyclodextrin), and their platinum (II) complexes, 1 ([Pt (L1)Cl2]·8H2O) and 2 ([Pt (L2)Cl2]·4H2O), were successfully synthesized. As revealed by UV-Vis and CD spectroscopic studies, both complexes mainly adopt a non-intercalative mode with DNA. The interaction between platinum complex 1 and DNA was obviously observed in agarose Gel Electrophoresis. Meanwhile, two ligands L1, L2 and platinum complex 2 have no obvious interaction with DNA. The difference interaction between complexes 1, 2 and DNA should be ascribed to their different structures.
Synthesis, Structure and Properties of a Novel Metal-Organic Coordination Polymer, [Zn (NH3)2(BDC)]n
Authors: Wu Ning Ning , Guo Can Xiong , Wu Gui An , Cai Zhao , He Wan Hong
Published: September 2013

A novel one-dimensional metal-organic coordination polymer, [Zn (NH3)2(BDC)]n (BDC=1,4-benzenedicaboxylate), has been synthesized by solvent evaporation method through self-assembly of Zn (II) salts with terephthalic acid ligand in ammonia aqueous solution. Single crystal X-ray diffraction analysis indicated that each Zn (II) was coordinated by two nitrogen donors from two NH3 and two oxygen counter donors from terephthalic acid ligand. The adjacent zigzag chains are arranged in a parallel fashion and linked by interchain hydrogen bonding interaction and π-π stacking interactions into higher-dimensional framework. The compound has also been characterized by CHN elemental analyses, Single crystal X-ray diffraction analysis, powder X-ray diffraction (PXRD) analysis, Fourier transform infrared (FT-IR) spectra, Thermalgravimetric-differential scanning calorimetric (TG-DSC) and Solid-state nuclear magnetic resonance (NMR), etc. Results showed that the framework of compound was stable at the temperature up to 246°C. The desolvated product [Zn (BDC)]n, which was obtained by removal of molecular NH3 from [Zn (NH3)2(BDC)]n, can be transferred to the different skeleton structures through coordinating different small hydrogen-bond-forming molecules.
Preparation of TiO2 Photocatalysis Antibacterial Ceramics
Authors: Ding Jun
Published: September 2013

Among various inorganic antibacterial materials, TiO2 photocatalysis antibacterial materials possess unique properties including long lifespan, nontoxicity, high temperature resistance as well as high physical and chemical stability. More significantly, they are largely involved in many photocatalytic effects such as degradation of organics, purification of air, sewage disposal and self-cleaning.
Research on Temperature Effect of Autogenous Deformation and Mechanical Properties of HPC
Authors: Gan Xue Hong , Jiang Chen Hui , Huang Shui Liang
Published: September 2013

The temperature history of HPC remarkably affects their volume stability and mechanical properties, but no enough attention is pay to it in the literature. In this paper, for the purpose of clarifying the temperature effect of above-mentioned behaviors, a series of tests on autogenous deformation, compressive strength and elastic modulus of HPC are carried out. The outcome of research as follows: surrounding temperature intensely influences autogenous strain and mechanical indices; elevated temperature not only results in increased shrinkage strain, compressive strength and elastic modulus, but also accelerates their rates of development.
Microstructure and Hardness of 7055 Aluminum Alloy Processed by Circular Cryogenic-Aging Treatment
Authors: Wang Hong Ming , Li Guirong , Cai Yun , Zhao Yu Tao , Wang Jun Jie , Gu Kai Xuan , Zhang Hong
Published: September 2013

7055 aluminum alloy was processed by circular cryogenic-aging treatments for four times. Some characters such as precipitates, dislocation density, crystal structure and micro hardness were studied in detail. It is showed that the sizes of precipitates are decreased from several hundred nanometers to 100nm with the increase of cycle index. The main components are AlZn or AlZnMg phases. The hardness test result illustrates that the micro hardness arrives at 232HV after circular cryogenic-aging treatment for twice. The corresponding precipitates exhibit high density and complex sizes. The sizes are in the range of 50-200nm.
Influence of Extrusion Methods on Microstructure of Mg-Al-Zn Alloy
Authors: Cai Yun , Li Guirong , Yuan Xue Ting , Wang Hong Ming , Zhao Yu Tao , Wang Jun Jie
Published: September 2013

The correlation between the deformation behavior and the microstructure of AZ31 magnesium alloy processed by as-extruded and ECAP is investigated in this paper. The grain size of as-extruded AZ31 magnesium alloy is about 30μm which dues to basal and twinning. Twinning is the main deformation behavior for as-extruded AZ31 magnesium alloy. The deformation of as-extruded is mainly caused by basal slip and twinning. The grains of ECAP are further refined to 6μm. With little amount of twins, the refinement of AZ31 magnesium alloy is caused by non-basal sliding. For ECAP precessed sample, grain boundary sliding happens and the proportion of high-angle grains are improved, which makes grain boundary sliding easier. The main deformation mechanism of ECAP is non-basal slip and grains boundary sliding.
High-Temperature Oxidation Resistance of Austenitic Stainless Steels
Authors: Li Dong Sheng , Li Dan , Dou Hong , Gao Pei , Liu Yu , Chen Xiao Jun , Jiang Xin Chun , Pei Jing Juan
Published: September 2013

The oxidation kinetic curves of four kinds of austenitic stainless steel at 700°C was measured by weighting method. It is showed that the oxidation curves of those austenitic stainless steels follow the parabolic law. The mass gain of 800Al steel. is the least of all. The surfacemorphology and structure of the oxide scale were studied by scanning electron microscopy and X-ray diffraction methods. It is found that adense oxide scale formed at 700°C in all four austenitic stainless steels. In austenitic stainless steel with high Mn content, scales are mainly composed of Mn2O3 and the spinel MnFe2O4. Scales of austenitic stainless steel with high Cr content but without element Al are composed by Cr2O3 and the small amount of spinel FeCr2O4 . Scales of austenitic stainless steel with element Al and Cr are composed of (Fe0.6Cr0.4)2O3 and Al oxide, showing the excellent oxidation resistance property.
Investigation on the Reaction of Refractories with 16MnRE Steel
Authors: Wang Dong , Guan Ye Feng
Published: September 2013

When teeming rare earth treated steels the nozzle blockage occurred so frequently that seriously interferes the application of RE in steels. In this study we tried to investigate the relationship between the wettablility of 16MnRE steel and nozzle materials. The results showed that the weakest wettability of steel liquid was observed on fused silica among the six nozzle materials. Next came zircon and high-alumina nozzle. It has no obvious difference between the 16MnRE steels when final deoxidized containing and not containing Al addition. The wettability of 10Ti steel was weaker than 16MnRE steels on zircon nozzle. The clay nozzle was corroded by the precipitate from steel liquid.
Analysis of Silicone Rubber Elastomer Elastic Failure in Small-Size Flexible Joint at Low Temperature
Authors: Wang Chao , Ren Jun Xue , Liu Yu , Hao Wen Qiang , Yang Jing Xian
Published: September 2013

In order to study the performance on silicone rubber elastomer in small-size flexible joint at different temperatures, a series tests for two miniature flexible joints (joint-SR1 and joint-SR2) with the same structure and different formula of silicon rubber elastomer (phenyl silicon rubber and dimethyl silicon rubber) were conducted. Axial compressive stiffness and bending stiffness at various temperatures (-60 °C~20 °C) and vessel pressures (1MPa~8MPa) were studied. Results show that the axial compressive stiffness and bending stiffness of joint-SR1 remain stable throughout the temperature range of-60 °C~20 °C, while those remain stable throughout the temperature range of-40 °C~20 °C and become to be infinite at-50 °C due to the elastic failure of elastomer material for the joint-SR2. Analysis indicates that the reason that elastomer of joint-SR2 lost elasticity at-50 °C is not glass-transition but crystallization. The phenomenon of elastic failure did not appear throughout the temperature range-60 °C~20 °C for the joint-SR1 elastomer is due to the existence of phenyl side-group substitute. The modified chain content of silicone rubber not only affects the process of crystallization inhibition but also the crystallization rate. The rubber with phenyl or other bulky side-group could destroy the crystal of silicone rubber at low temperatures, which is beneficial to be applied in small-size flexible joint.