bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization and Recovery Evaluation of Elastic Knitted Fabric
Authors: Lin Chin Mei , Lou Ching Wen , Yan Ruo Si , Lu Po Ching , Lin Jia Horng
Published: April 2015

The present study aims to investigate the effects of the ratio of different rubber threads on the elastic, tensile, air permeability, andfar-infrared emissivity properties ofelastic warp-knitted fabric. Polyester filaments and rubber threads were applied as warp yarns while bamboo charcoal (BC)/Nylon (NY) filament was used as weft yarn to fabricate elastic knitted fabric (EKF) by using Velcro Crochet Machine. The four different ratios of rubber threads in warp direction were 0 %, 25 %, 50 % and 100 %. The result revealed that with the increase in weight ratio of the rubber thread, the air permeability decreased while the tensile elongation tended to increase in both warp and weft directions.
Effects of Counts of PET Yarns and Spandex Fibers on the Properties of Tubular Knitted Fabrics
Authors: Lin Jia Horng , Lu Po Ching , Hu Jin Jia , Chen Yueh Sheng , Lou Ching Wen
Published: April 2015

This study examines how the counts of PET yarns and spandex fibers influence the properties of tubular knitted fabrics. PET yarns and spandex fibers with different counts are combined to form wrapped yarns, which are then made into tubular knitted fabrics. The surface of the knitted fabrics is observed, after which the knitted fabrics are tested for their tensile strength. The test results show that the tensile strength and thickness of the tubular knitted fabrics both increase as a result of the increasing content of PET yarns; however, the content of either spandex fiber or PET yarns is not correlated with the deformation of the tubular knitted fabrics.
The Study of Health and Insulation Composite Recycling Far Infrared Fiber Laminated Non-Woven
Authors: Lou Ching Wen , Hsing Ya Lan , Hsing Wen Hao , Hsieh Chien Teng , Lin Jia Horng
Published: April 2015

In this study the experiment used the two kinds of fibers, respectively are the recycled far-infrared polyethylene terephthalate (RFPET) fibers and the low melting temperature polyethylene terephthalate (LPET) fibers. Needle punching and compare with laminated in different layers, through hot pressing to make the fabric thin, observation and testing , surface observation, air permeability test, stiffness test, and far infrared emissivity test. The study shows the far-infrared radiation rate and will not increase because of the laminate, but is a relationship with a thickness comparison.
Thermal Degradation Behavior of Composites with Liquid Crystalline Epoxy and Aluminum Nitride
Authors: Moon Hee Jung , Lee Bong Soo , Cho Seung Hyun
Published: April 2015

Liquid crystalline epoxy, 4,4’-Diglycidyloxy-α-methylstilbene (DOMS) was synthesized and Aluminum Nitride reinforced DOMS composites were fabricated by melt blending with sulfanilamide (SAA) as a curing agent. Thermal degradation behavior was investigated by thermogravimetric analysis (TGA) under nitrogen atmosphere at the temperature range from 30 to 1000°C. Activation energies for decomposition (Ed) by TGA were determined as a function of conversion by weight loss process.
Switching Behavior of Titania-Zinc Oxide Composites Thin Films
Authors: Mohamat Kasim Shafaq Mardhiyana , Akma Shaari Nor Azira , Bakar Raudah Abu , Herman Sukreen Hana
Published: April 2015

Single layer of titanium dioxide (TiO2) is common metal oxide in fabricating memristor device. In this study, two types of memristor with composite metal oxide thin films will be demonstrated. The two types of memristor are titanium dioxide (TiO2) thin film coated on zinc oxide (ZnO) thin film and ZnO coated on TiO2 thin film. Sol-gel spin coating method was to coat metal oxide thin film and sputtering method for depositing the metal contact. Platinum (Pt) was selected as the top electrode and indium tin oxide (ITO) as the bottom electrode. The electrical characteristics were defined by performing I-V measurement using two point probe equipment. I-V characteristics showed shape of pinched hysteresis loop for both samples. Sample with TiO2 coated on ZnO has slightly higher Roff/Ron ratio than sample ZnO coated on TiO2 which means it more memristive than another one. The cross-section of sample with TiO2 coated on ZnO had been performed as well by using Field-Emission Scanning Electron Microscopy (FESEM).
Crack Propagation of Aluminum Alloy 2024 T351 under Constant Amplitude Loading Using Crack Closure Concept
Authors: Hadjoui Fethi , Benachour Mustapha , Benguediab Mohamed , Hadjoui Abdelhamid
Published: April 2015

The crack propagation behavior in a 2024 T351 Aluminum Alloy under constant amplitude loading has been studied. This study is analyzed in term of crack opening load measurements using a compliance technique. The results obtained under constant amplitude fatigue tests show that different crack propagation stages can be identified. Significant effects due to load ratio changes have been quantified.
Experimental and Numerical Characterization of Self-Compacting Concrete «Using Construction Waste»
Authors: Hermime Hassiba , Bouafia Youcef , Benakli Sarah
Published: April 2015

This work carries an experimental study on the composition and the characterization of the self-compacting concretes made starting from waste of construction with comparisons which were made by contribution with the vibrated concrete. Studies on the workability and the compactness of material were made and this in a fresh state and a hardened state. Five different mechanical tests were performed: compression, direct tensile, splitting tensile, 3 points binding and failure to the shear force. Confrontations of the test results compared to formulas for calculating the shear force were realized. All the test results showed an increase in terms of resistance for SCC contribution to the VC, except the direct tensile test which gave values slightly lower. The SCC improves the failure load notably and gives better mechanical performances.
Software for Design and Assessment of Rotationally Symmetrically Loaded Reinforced Concrete Slabs in the Shape of Circle or Ring
Authors: Vaskova Jana , Matečková Pavlina
Published: April 2015

The subject of this paper is an universal software for reinforced concrete annular and circular slabs reinforced in the radial and tangential direction. Such slabs are used for roof and ceiling structures of buildings. The software can be used for design and assessment of rotationally symmetrically loaded annular and circular reinforced concrete slabs with arbitrary supports and span. Based on user's choice, the software proposes solutions to not only meet all the design principles, but especially ultimate limit state and serviceability limit state.
Evaluation of Seismic Behavior in Non-Seismic Concentrically Braced Frames
Authors: Yeom Hee Jin , Jung Eun Bi , Yoo Jung Han
Published: April 2015

SCBFs (Special Concentrically Braced Frames) have been praised for considerable strength, high lateral stiffness, economic feasibility and good performance of seismic loads, which make engineers widely use SCBF as lateral-load resisting systems in buildings and have researchers develop design requirements. Compared to the extensive research of SCBF, comparatively little information is currently available on the performance of SCBFs designed and constructed before the early 1990’s. Before the early 1990’s, CBFs (Concentrically Braced Frames) design requirements were substantially less restrictive. As a result, many existing structures designed to these requirements may not exhibit desirable behavior in a seismic event. Existing CBFs that do not meet modern SCBF criteria shall be referred to herein as NCBFs (Non-Seismic Concentrically Braced Frames). In this study, FE (Finite Element) analysis was carried out. The detailed inelastic FE models were verified, which are based on the preceding research. Finally, these models were compared to evaluate the seismic performance of NCBFs.
Adsorption of Cr (III) Ions on the Surface of Diatomite
Authors: Tazhibayeva Sagdat , Alzhanov Amir , Musabekov Kuanyshbek , Zhalishev Kairat
Published: April 2015

The conditions of adsorption of Cr3 + ions at the surface of diatomite are optimized. It was shown that the adsorption of Cr3 + ions on diatomite depending on the initial concentration is 1,8-6,9 mg /g, which is caused by the occurrence of the ion exchange reaction between the silanol groups of diatomite and Cr (III) ions. The effect of pH on the binding of Cr3 + ions with diatomite was studied. It was established that acidification of the medium leads to a decrease in the degree of extraction of Cr3 + ions from solutions, due to protonation of SiOH-groups of the diatomite surface with H + ions of acids to SiOH2+. It is suggested that, along with the adsorption of Cr3 + ions on the surface of diatomite heterocoagulation of diatomite particles and hydroxocomplexes of Cr3 + ions is possible.
Biodegradable Braided Coronary Stents: Effects of Cross-Linking Concentrations on Surface Structure and Compressive Strength
Authors: Lin Jia Horng , Wen Shih Peng , Ueng Kwo Chang , Chen Yueh Sheng , Lou Ching Wen
Published: April 2015

This study proposes coronary stents in a manner of reticular tube, which are made by applying a braiding method. Polyvinyl alcohol (PVA) plied yarns are braided into hollow braids on a 16-spindle braid machine, followed by being cross-link treated to form the coronary stents. The surface observation and a compressive test are used to evaluate the resulting products. The test results show that cross-link treatment does not pertain to the reticular, tubular manner of the braids. However, a low cross-linking concentration results in a light shade and a greater compressive strength in the coronary stents. In addition, the acidification of the cross-linking solution affects the compressive modulus. The coronary stents presented by this study are proved to be biodegradable and have compressive strength and a reticular-and-tubular form.
Hydrothermal Synthesis and Hydrophilic Performance of Silica Modified Titanium Surfaces
Authors: Wu Yu Ren , Ko Chia Ling , Wu Hui Yu , Lin Jia Horng , Chen Wen Cheng
Published: April 2015

It is well known that titanium (Ti) has excellent properties of anticorrosion, biocompatibility and low modulus that would be applied in many clinical applications. The aim of this study wants to increase the hydrophilicity of titanium surface through silanization and then grafted with hydroxyapatite (HA) by hydrothermal synthesis method. Physiochemical analysis of grafting plate substrate was observed by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), and contact angle analysis. The surfaces with silanization were strongly interaction between SiO2 and TiO2, and thus Ti-O-Si-bonds formed having larger surface areas but only showed a little improved hydrophilicity. The hydrophilicity of Ti substrate was largely increased after the hydrothermal process. Compared with Ti surface without any surface treatment, the surface which modified with hydrothermal synthesis can improve the wettability of Ti surfaces. Furthermore, the Ti surface through silanized modification before hydrothermal synthesis held good calcium phosphate precipitates existing due to the better calcium ion combined ability with polar bond of aldehyde group (Ti-O-Si-CO-).
First-Principles Calculation of Al-Cu-Mg Alloy Strengthening Phase
Authors: Ma He , Chen Li Jia , Guo Lian Quan , Leng Li , Lin Lin
Published: April 2015

In this study, equilibrium lattice parameters, heat of formation and cohesive energy of four kinds of typical phases with different structure intermetallic compound in Al-Cu-Mg alloy were investigated by first-principles calculations based on density functional theory via CASTEP software. The calculation results are analyzed and show that ternary strengthening phase Al2CuMg generated first when Mg content is higher, while binary strengthening phase Al2Cu or Al3Cu2 first generated and more stable when Mg content is low in Al-Cu-Mg alloy which indicates that element Cu and Al alloying capacity significantly higher than that of Mg and Al element.
Corrosion Protection Behavior of γ-APS Films on Low Carbon Steel
Authors: Zhu Xiao Fei , Li Tian Yi , Shan Hou Zhuang , Niu Ling , Liu Lei
Published: April 2015

The use of a silane coupling agent (3-aminopropyltriethoxysilane) to improve the anticorrosive property of low carbon steel was assessed by DC polarization test and infrared spectroscopy. These tests indicated that the optimal hydrolysis system of γ-APS was available at 25 °C, pH 10, and with 7 vol % APS, 28 vol % absolute ethanol and 65 vol % DI water. Factor of silane volume in hydrolysis systems played an important role in the hydrolysis effect of γ-APS.
Synthesis and Characterization of Alkyl-Substituted Polyaniline by Using Ammonium Persulfate as both Oxidant and Dopant
Authors: Li Xin , Wan Mei Xiang , Li Cong Ju
Published: April 2015

Poly (o-toluidine) (POT), poly (m-toluidine) (PMT) and poly (p-toluidine) (PPT) were chemically oxidized by ammonium persulfate (APS) as both oxidant and dopant through a very simple self-assembly process. The structure characterizations by elemental analysis, XPS and FTIR demonstrated that APS is served as both oxidant and dopant due to the proton acid produced during polymerization, which is proven by the decreasing pH value of the reaction solution along with the increase of polymerization time. Besides, the influences of the alkyl-substitution position on the molecular structure, polymerization process, morphology and electrical properties are also discussed.
Preparation of Barium Aluminate with BaCO3 and Al(OH)3
Authors: Li Jun Qi , Wang Ru Kai , Chen Chao Yi
Published: April 2015

Synthesizing barium aluminate using barium carbonate and aluminium hydroxide, the optimum conditions in reaction process of synthesizing barium aluminate were discussed. The phase of the products was characterized by XRD. The results indicate that the optimal synthesizing conditions are established with the yield of 88.43% when the roasting time is 80min, the roasting temperature is 1350°C and molecular proportion of Al2O3/BaO is 1.1. The bulk density of barium aluminate is 1.5g/cm3; average particle size is 89.808μm; surface mean size is 65.915μm; and the specific surface area is 0.0246016m2/g.
Cu-Ni Nanocatalysts in Mesoporous MCM-41 and TiO2 to Produce Hydrogen for Fuel Cells via Steam Reforming Reactions
Authors: Abrokwah Richard Yeboah , Deshmane Vishwanath G. , Owen Sri Lanka , Kuila Debasish
Published: April 2015

We have synthesized mesoporous SiO2(MCM-41) and TiO2encapsulated bimetallic Cu-Ni nanocatalysts using an optimized one-pot hydrothermal procedure. The catalysts were characterized using BET, XRD, TGA-DSC and HRTEM techniques. While bimetallic Cu-Ni/MCM-41catalysts have high surface area- 634-1000 m2/g, Cu-Ni/TiO2yields surface area of 250-350 m2/g depending on the metal loading (5-10 wt%). The XRD studies confirmed a long range ordered structure in Cu-Ni/MCM-41 and the presence of the catalytically active anatase phase in the crystalline Cu-Ni/TiO2. The results from HRTEM studies were consistent with the mesoporosity of both supports. These catalysts were tested for methanol conversion and H2/CO selectivity via steam reforming of methanol (SRM) reactions in a fixed bed reactor. There is a distinct difference in the performance of these two supports. Bimetallic 3.33%Cu6.67%Ni/TiO2catalyst showed an impressive 99% H2selectivity at as low as 150°C and a maximum conversion of 92% at 250 °C but 3.33%Cu6.67%Ni/MCM-41 catalyst did not show any H2selectivity at 150°C and only ~12% conversion at 250°C. The effect of each support and relative metal loadings on the activity and selectivity of the SRM reaction products at different temperatures is discussed.
Structure and Characterization of Strong Acid Cationic Exchange Fiber
Authors: Li Ming Yu , Yang Da Yong , Zeng Qing Xuan , Wang Wen Qing , Li Zhi Hao
Published: April 2015

A novel polypropylene strong acid cationic exchange fiber (SACEF) was prepared by sulphonation reaction of polypropylene graft styrene (PP-g-St) fiber. The structure of SACEF was characterized through IR, TG, DTG, EA and SEM testing. The physicochemical properties of PSACEF, including adsorption capacity, adsorption dynamics, water content, and regeneration stability were evaluated. The results showed that the adsorption capacity of SACEF was 4.42 mmol·g-1. Infrared spectra indicated that hydrogen on the benzene ring was substituted by sulfuric acid group. TG and DTG confirmed that SACEF was more stable under the 250 °C. The adsorption dynamics suggested that the adsorption on SACEF was fast and it nearly reached equilibrium within 1 min. The water content of SACEF was 55%~60%. SACEF showed good regeneration performance. The adsorption capacity was constant after being used many times.
Synthesis, Characterization, and Properties of POSS-Epoxy
Authors: Wen Miao Qin , Jiang Tao , Ding Ying
Published: April 2015

Polyhedral oligemeric silsesquioxanes epoxy (POSS-EP) was prepared from 3-glycidyloxy-propyl-trimethoxysilane (KH-560) and tetramethylammonium hydroxide (TMAH) by hydrolytic condensation. POSS-EP was characterized using fourier-transformed infrared spectroscopy (FTIR), thermal gravity analysis (TGA) and gel permeation chromatography (GPC). When the mass ratio of KH-560 and 25wt% TMAH was 20:1 and the temperature of hydrolytic condensation was 80°C, T8 was the majority and certain a mount of T10. The temperature of POSS-EP in weight loss 5wt% and the maximum degradation rate was approximately 200°C. The residual weight for POSS-EP at 800°C was 33.5wt%. After the cotton fabric was treated with 5wt% POSS-EP by using toluene as solvent, its carbon residue was improved 60 times than untreated .
Microstructural Characterization of 3C-SiC Layers, Grown Epitaxially on 4H-SiC Substrates by CVD
Authors: Polychroniadis Efstathios K. , Sall Mamour , Chandran N.
Published: April 2015

This work was performed on 3C-SiC layers grown on 4H-SiC substrates by chemical vapour deposition after a surface pre-treatment using GeH4 gas. By means of TEM, the effects of different GeH4 fluxes in the 3C layer quality has been studied and compared. An optimal GeH4 flux permits to drastically reduce twin boundaries but another type of defect occurs and has been widely studied in this paper.
Research on Metallographic Structures for Low-Alloy Steel after Fire Damage
Authors: Chen Wang , Jin Chen , Wang Yin Pei
Published: April 2015

In chemical processing plants and petroleum refineries, the pressure vessels and pipelines suffered often from fire accidents and thus resulted in the metal materials were in overheating state. Elevated temperature could cause the changes in metallographic structure and have unfavorable effects on material mechanical properties. In order to understand better the influence laws of overheating on metallographic structures and material mechanical properties, the methods of theoretical analysis and experimental research were used and the effects of thermal exposure temperature, duration time and cooling rate on microstructure of low-alloy steel 12MnNiVR, were studied systematically. The study can provide basis data for the material properties database of metal material suffered from fire accident, and afford technical supports in the key technologies on fire damage FFS (Fitness-For-Service) integrity assessment.
Analysis and Explanation of Agglomeration Phenomenon Based on Raman Spectrum
Authors: Li Hai Ling , Sun Geng Xin , Jiang Shui Qing , Bin Sheng
Published: April 2015

In this paper, from the standpoint of Raman spectrum research aspect in material science, Raman spectrum analysis of graphite and diamond microcrystal retained by gallium phosphide nanoparticles is introduced. We found that molecular configuration of basic fuchsin adsorbed on gallium phosphide nanoparticles through experiments. Based on these, Raman scattering is used for analyzing basic fuchsin adsorbed on surface of gallium phosphide nanoparticles. Moreover, we discuss the corresponding meanings of agglomeration phenomenon from the perspective of material.
Hybrid Plasmonics Waveguide Properties of Dielectric Nanowires Coupling with Metal Substrate
Authors: Zhang Yi Lei , Wang Yong Gang , Yu Li
Published: April 2015

A hybrid plasmonic waveguide system consisting of a high-permittivity cylinder waveguide embedded in a low-permittivity dielectric deposited on a metal substrate is comprehensive investigated. With the strong coupling between dielectric cylindrical waveguide mode and the long-range surface plasmon polaritons (LRSPP) mode of a thin metal film, the basic waveguiding properties, including the effective mode area, the propagation length, the mode character, and the figure of merit (FoM) can be achieved. Our results may provide valuable references for waveguiding metal -supported dielectric nanowires for practical applications. An investigation of the effect of structural perturbations indicates that the disturbance of the dielectric nanowires of our proposed waveguide with different surrounding dielectric layer would have a great influence on the experiment results.
Effect of Heat Treatment on Microstructures and Mechanical Properties of A356 Alloy by Low Pressure Casting
Authors: Yu Xiao Jian , Lu Ya Lin , Zhu Fu Xian , Li Xing Cheng
Published: April 2015

Automobile wheel of A356 alloy was cast by low pressure casting process. The effect of heat treatment process on microstructures and mechanical properties of A356 alloy cast was discussed. The results indicated that optimal parameters of heat treatment process for A356 alloy included solution temperature of 535°Cand holding time of 4.5hours, aging temperature of 145°Cand holding time of 4hours. Ultimate strength of A356 is 270MPa and elongation rate is 10%. Meanwhile, the microstructure has been apparently improved. The eutectic silicon particle became more spheroidal and distributed uniformly in matrix.
Analysis and Optimization on Injection Molding Process of Double Helical Gear Based on Moldflow
Authors: Jiang Chang Yong , Shen Hong Lei
Published: April 2015

In view of a kind of a plastic double helical gear in some office electrical equipment, injection molding process analysis was done, by means of Moldflow,to create feed system and cooling system for Moldflow analysis of helical gear, to make numerical simulation analysis, verification and optimization of injection molding process, to obtain some major parameters such as temperature, pressure and time to meet molding requirements of injection molding process of double helical gear.
Influence of Slag on Water Resistance of Magnesia Phosphate Cement
Authors: Wang Zhe , Ding Yao Kun , Li Si Rui
Published: April 2015

Effect of different curing conditions on the mechanical properties of magnesium phosphate cement (MPC), and the water resistance of MPC was improved by adding slag, the influence of slag on component and microstructure of the hydrated product were studied in this paper. The additive amount of slag was 0% ,10% , 20%, 30% and 40% separately in the ratio of total amount of MPC. It indicates that the compressive strength and flexural strength increase by about 30%,40% when the amount of slag reaches 10% of phosphate cement, respectively , and the dissolution of some phosphate which has not reacted can be prevented when cured in water for days, it improves the pH value of the solution, so the main hydration product-MgKPO4·6H2O hard to be dissolved under alkaline environment resulting in the decreasing of porosity ,and the decrease of strength would be controlled.
Organic Light Emitting Properties of the Functional Pyridine-Containing Diacylhydrazones
Authors: Yuan Kun , Lv Ling Ling , Wang Xiao Feng , Zhu Yuan Cheng
Published: April 2015

The pyridine-containing diacylhydrazones derivatives are functional organic light emitting molecular materials. In this paper, The S0 ground states and the S1 excited states of the four pyridine-containing diacylhydrazones compounds were optimized with density functional theory (DFT) at B3LYP/3-21+G level and single-excitation configuration interaction at CIS/3-21+G method, respectively. We discussed in detail the relationships between the molecular orbital energy, absorption and emission performances and the structures of the four compounds. In addition, the analysis on frontier molecular orbital (FMO) energy gaps indicated that the stronger the conjugations are, the much more red-shift of the absorption spectrum will be. According to the calculated absorption and emission spectra data, it can be conclude that four pyridine-containing diacylhydrazones compounds are one of the alternative electron transporting and photoactive materials.
Pervaporation Separation of Cyclopentadiene/Methylcyclopentadiene Mixtures from Cracking C5 Fractions Using Polyimide Membranes
Authors: Chen Jin Qing , Lv Hong Ling , Yao Ya Qi , Chen Bing
Published: April 2015

Polyimide membrane pervaporation was introduced to separate the costly diene mixtures of cyclopentadiene/methylcyclopentadiene (CPD/MCPD) from cracking C5 fractions. Four kinds of membrane solutions were prepared and two kinds of polyimide homogenous membranes were fabricated by thermal imidizations using the dianhydrides (BPADAand PMDA) and the diamines (ODA and DDS). The effect of the casting solutions viscosity on the membrane formation was revealed, and the formation of functional groups and the synthesis mechanisms of the thermal imidizations were indicated by FT-IR. The adsorption behaviors and the pervaporation performances were studies for BPADA-ODA and PMDA-ODA membranes. The results show that the permeation fluxes are 164g∙m-2∙h-1 and 4.2g∙m-2∙h-1 for BPADA-ODA and PMDA-ODA membranes respectively, while the separation factor are 1.93 and 8.9 for these two membranes respectively. 88.5 wt% concentration of MCPD was achieved in the circulated feed side ultimately.
The Numerical Simulation of Effective Elastic Response for WC-Co Cemented Carbide
Authors: Li Pei Luan , Huang Zi Qian
Published: April 2015

By the use of finite element method, this paper predicts the effects of the shapes of reinforcements with different ductility (Co) on the effective elastic response for WC-Co cemented carbide. This paper conducts a comparative study on the material properties obtained through theoretical model, numerical simulation and experimental observations. Simulation results indicate that the finite element method is more sophisticated than the theoretical prediction.
Preparation and Structure of Amino-Modified Multi-Walled Carbon Nanotubes
Authors: Li Yun Hua , Sun Jun Fen
Published: April 2015

Carboxylic multi-walled carbon nanotubes (MWCNTs-COOH) were modified by using ethylene diamine (EDA) to prepare amino-modified multi-walled carbon nanotubes (MWCNTs-NH2). The chemical structure of MWCNTs-NH2 was characterized by FT-IR, Raman spectroscopy, X-ray diffraction (XRD) test, TG analysis and elemental analysis. The results show that MWCNTs-COOH was effectively modified by EDA. Key words: MWCNTs-COOH; ethylene diamine; chemical modification; elemental analysis
ArF Excimer Laser Assisted Solution Based Metal Induced Crystallization of Amorphous Silicon Films
Authors: Dai Wen Yun , Jin Jing , Hui Chao Xian , Liu Can , Yuan Zhi Jun , Shi Wei Min
Published: April 2015

Amorphous silicon films with and without spin-coating aluminum-salt-solution are treated by 193nm ArF excimer laser with different laser energies. It is observed that the crystalline fraction increases along with the laser energy. By comparation, with the help of Al, higher crystalline volume fraction and lower in-plane stress can be achieved at the same laser energy (2.9mJ). Large grain size of 200~300nm and maximum crystalline fraction of 82.3% are obtained in Al-salt-solution spin-coated sample, which is treated with laser energy of 3.2mJ,and its carrier mobility is 56.3cm2/Vs.
Reduction Kinetics of Nano-Sized Nickel Ferrite for the Production of Metallic Alloys
Authors: Abdel Halim K.S. , Ramadan M. , Messaoudene N. , Aichouni M. , Al-Ghonamy A.A.
Published: April 2015

Nanostructured materials have attracted considerable attention in recent years because of their unique and amazing properties. With a high surface activity due to their small particle size, enormous surface area and specific mechanical properties, it has been used for various engineering purposes including chemical, mechanical and civil engineering applications. The rapid development of nanostructured materials and nanotechnology will change the traditional processes of fabrication and applications of construction materials. nanosized materials can be used in construction industry to produce lighter and stronger structural composites such as modified steel. The present work introduces a novel idea for the production of metallic alloys from nanosized nickel ferrites using powder technique routes. nanosized nickel ferrite (50 nm) is being used as starting material for the production of metallic alloy containing iron and nickel. The prepared alloys were characterized physically and chemically through X-ray diffraction and optical microscope. The composition of these alloys is often a key factor to control the mechanical, chemical and physical properties of the synthesized alloys. The reduction processes take place in a stepwise manner via the formation of a series of intermediate oxides. The microstructures of the produced alloy together with the kinetics data obtained from reduction process were used to elucidate the reduction mechanism under isothermal conditions.
Study on Mix Proportion of C80 High-Strength Tri-Admixture Concrete
Authors: Wang Hai Chao , Chen Chen , Liu Gang , Shi Jie , Zhao Chun He
Published: April 2015

This paper studies the engineering application of C80 concrete with the feasibility of the raw material and production process. According to the design principle of high strength concrete and the method of the orthogonal design, The C80 high-strength tri-admixture concrete which includes fly ash, slag and volatilized silica was developed by using the local admixture. Further, the results show that the designed of the high-strength concrete based on the local material is available by adjusting and optimizing the amount of admixture reasonably. At last, the green production goal is achieved by reducing the dosage of cement, consuming industrial waste materials which playing an important role in its activity.
Stochastic Filtering Back Analysis of Elastic Modulus of Box Shaped Beam
Authors: Yu Bo , Hong Tao , Zhang Jian
Published: April 2015

With the development of civil engineering, the box shaped beam has been widely applied in practical engineering. In general, it is composed of concrete and steel and compared with mechanical analysis, little research has been carried on the back analysis of elastic modulus of box shaped beam. With degraded solid element theory, the shell element is deduced and the displacement function is obtained. The necessary observation revision equation and Kalman regenerative matrix are derived. The stochastic filtering back analysis steps of elastic modulus of the box shaped beam are presented and the analytical procedure is compiled. Through analysis of a classic example, some important conclusions about stochastic filtering back analysis of elastic modulus of box shaped beam are obtained.
Dynamic Behavior of T Thin-Wall Steel Member Subjected to Lateral Explosive Loading
Authors: Wu Jian Yu , Long Yuan , Ji Chong , Gao Fu Yin , Zhao Hua Bing
Published: April 2015

Based on LS-DYNA and Lagrange-Euler coupling algorithm, the nonlinear dynamic response of T-steel under external explosive loading of condensed explosives was studied with numerical analysis, and the influence of contact state was mainly discussed. The numerical results showed that the damage effect of steel members under contact explosion was stronger than the non-contact explosion; the axial deformation was the biggest at the center and decreased gradually from the center to surrounding area; under contact explosive, there was a displacement platform at the initial stage of the deformation of the nodes at the farther distance from the center; due to the web, under non-contact explosion, the central tangential deformation was the smallest, and the deformation sharply increased firstly and decreased gradually next from the center to nearby nodes.
Research on the Screening of Degrading Fungi for Poly (vinyl alcohol) Film and the Effect of Additives
Authors: Hao Xi Hai , Yi Xiao Peng , Li Ding
Published: April 2015

Poly (vinyl alcohol) (PVA) was used as the sole carbon source in the medium to isolate PVA-degrading fungi from an activated sludge which obtained from water-soluble PVA packaging film factory. The PVA-degrading fungi were screened after transparent circle experiment and were preliminary identified through morphology and optical microscope observations. The qualitative and quantitative researches of the effect of additives on PVA degradability were investigated by transparent circle experiment and UV spectrophotometry, respectively. The results showed that the degradation effect of the XP-02 was the best in ten PVA-degrading strain and was preliminary identified as penicillium. When the concentration of additives was 0.05 g/L, the biodegradation rate of PVA was increased with the addition of plasticizer (polyethylene glycol) (PEG), surface active agent (sodium dodecyl benzene sulfonate) (SDBS) and emulsifying agent (tween-80 or triton X-100) by 5.01%, 8.67% and 11.21%, respectively, which indicates that the additives in the PVA packaging film can increase the degradable effect. However, the optimum proportion of these additives in the PVA film to obtain the best degradability for the film is deserves the further investigation.
Numerical Approach of the Main Physical Operational Principle of Several Wave Energy Converters: Oscillating Water Column, Overtopping and Submerged Plate
Authors: Gomes Mateus das Neves , Espinel Lara Maria Fernanda , Iahnke Silvana Letícia Pires , Neves Machado Bianca , Moraes Goulart Marcelo , Medeiros Seibt Flávio , dos Santos Elizaldo Domingues , Isoldi Liércio André , Rocha Luiz Alberto Oliveira
Published: April 2015

In this work it is numerically studied the wave flow inside a tank and the main operational physical principle of three different wave energy converters (WEC): oscillating water column (OWC), overtopping and submerged plate. The wave energy converters are evaluated in laboratory and real scales. For all studied cases the conservation equations of mass, momentum and one equation for the transport of volumetric fraction are solved with the finite volume method (FVM). To tackle with water-air mixture, the multiphase model Volume of Fluid (VOF) is used. Several results showed the accuracy of the numerical approach for estimation of the physical phenomenon of wave flow inside tanks, as well as, its interaction with the studied devices. For the cases with geometrical optimization, Constructal Design is employed for geometrical evaluation of the devices. Results presented several theoretical recommendations about the influence of geometrical parameters (such as ratios between heights and lengths of OWC chamber and ramp of overtopping device and the distance from the plate to the seabed of wave tank) over the available power take off (PTO) in the OWC and submerged plate devices and over the amount of water stored in the reservoir of the overtopping device. Results showed the importance of geometric shapes over the devices performance. Moreover, it is evaluated the influence of several wave parameters (such as wave period and relative depths) over the fluid dynamic performance of the devices and geometrical parameters of the devices. It is noticed the non-occurrence of universal optimal shapes.
Effective Permeability and Transfer Properties in Fractured Porous Media
Authors: Rastiello Giuseppe , Bennacer R. , Nahas Georges , Bogdan Mateuz
Published: April 2015

Mesoscale analyses of cracked porous volumes are performed. The fluid flows through a multiphase volume comprising one macro-crack, macro-pores and random micro-porous solid inclusions. Mesostructures are defined by thresholding of spatially correlated Gaussian random fields.Transport through macropores and crack, as well as the diffusion in micro-porous solid inclusions, are taken into account. Homogeneous (without cracks) porous volumes illustrated the asymptotical behaviors. The corresponding macroscopic permeability tensors are obtained and correlated with the geometrical/statistical properties of the analyzed porous systems. A new equivalent electrical scheme, including shunt resistance, is proposed to evaluate the apparent diffusion coefficient. Macro-cracked porous volumes are then investigated.The increases in mass flux due to the crack, as well as the mass/energy exchanges with the surrounding porous medium, are quantified by direct numerical simulation. A drying region due to the macrocrack was illustrated and the corresponding apparent permeability was identified. For different geometrical configurations (macro-porosity, micro-porosity, macro-crack orientation and aperture) we quantify the macropore –crack interlink by comparing such structure with structure without possible flow between the macro-crack and the porous structure.The equivalence scheme between mass flow in cracked porous media and heat flow in porous media was underlined.
Simulation of the Acoustic Loads Generated in the Intersection of a Main Steam Line and its Safety Relief Valve Branch of a BWR Plant under Extended Power Uprate Condition
Authors: Ocampo-Ramirez Arturo , Hernández-Gómez Luis Héctor , Ruiz-López Pablo , Moreno-Cuahquentzi Noel , Urriolagoitia-Calderón Guillermo , Beltrán-Fernández Juan Alfonso , Urriolagoitia-Sosa G. , Fernandez-Valdés Dayvis
Published: April 2015

The structural integrity of a BWR nuclear power plant can be compromised due to severe dynamic loads. Acoustic loads coming from a Safety Relief Valve branch can be adversely amplified if the steam flow is increased at the Main Steam Piping. This phenomenon has been reported previously in one BWR nuclear power plant. Its steam dryer was fractured and loose parts were generated due to high-cycle fatigue. This event has driven the United States Nuclear Regulatory Commission to issue specific regulations to evaluate acoustic loads which would be detrimental to the BWR steam dryer. In this paper, the acoustic loads were simulated when the steam flow is incremented from normal operation conditions to an Extended Power Uprate condition. It was analyzed, when the output power was incremented 14% and 28%. The initial conditions were determined with Computational Fluid Dynamics under steady state condition. This data was used in subsequent transient analysis. The model of Large Eddy Simulation was used and the acoustic simulation was performed with the Fowcs Williams and Hawkings Method. The Power Spectral Density was obtained with Fast Fourier Transform. The frequency peaks were found between 148 Hz and 155 Hz. These results are consistent with those obtained with the Helmholtz model and other results reported in the open literature. The results show that the peak pressure can be increased up to six times in resonance conditions, corresponding to a power uprate of 28%.
Mine Gas Flow in the Porous Massif and CFD Tool
Authors: Staša Pavel , Kodym Oldřich
Published: April 2015

There is a still dangerous effect in the form of methane leakage from coal seams in areas where mining activity still continuing or took place in the past. The issue of mining gas flow is still a matter that is necessary to pay attention and try to find new ways to solve this set of phenomena, no matter if it is the mining corridors or the flow in the rock massif. The number of measures to gradually reduce risk has been taken to protect the population. Nevertheless, the current situation is generally rated as serious as those risks still remain valid. Leakage of mine gases depend on many natural and technical mining conditions. With the closure of mines and thus the end of the ventilation situation considerably worse. This paper deals with the flow of dangerous mine gas, methane, through the rock mass using numerical flow modeling using CFD program Fluent. Using CFD codes can gain insight on the phenomenon under review and the results to take appropriate measures in the form of active or passive intervention.
The Numerical Modeling of a Two Phase Flow under the Gravitation and Centrifuge Driving Forces
Authors: Kačur Jozef , Minár Jozef , Kišon P.
Published: April 2015

An efficient numerical approximation for two phase flow in 1D is presented. Mathematicalmodel is based on two Richard’s type equations using Van Genuchten-Mualem (vG-M) model for capillarypressure-saturation and hydraulic permeability versus saturation of wetting liquid. The wettingand non-wetting liquids are incompressible and immiscible. The method is suitable for determinationof soil parameters (as a tunning parameters in vG-M model) via solution of inverse problem. Wettingliquid (-water) is injected into the sample originally saturated with non-wetting liquid (-oil) by gravitation,or centrifuge driving forces. In a series of experiments we discuss noninvasive (easy-to-measure)measurement scenarios which are satisfactory in a solution of inverse problem.
Experimental Study of Parameters Affecting the Temperature of an Absorption Tube of Parabolic Trough Collector
Authors: Alfozan Adel Khalid , Al-Awairdy Saleh N.
Published: April 2015

In this paper some important parameters affecting the temperature increase of the fluid inside an absorption tube of parabolic trough collector have been experimentally investigated using the Design of Experiments (DOE) method. These parameters are: absorption tube length, fluids type and fluid flow rate. The design of an absorption tube as well as a solar parabolic trough collector has been changed into different ways in order to increase the fluid temperature inside the absorption tube. The design of experiments plays a major role in identifying which factors are significant in increasing the temperature absorption inside the tube. The DOE method was validated using an experimental setup that is designed and fabricated by the Department of Mechanical Technology at Riyadh College of Technology. The experiments have been done on all the factors considered randomly using factorial design by merging all the factors together to know which factors and their interactions can affect more on increasing the fluid temperature inside absorption tube. Eight experiments with three replicates have been chosen randomly. From the results it is seen that the most significant effective factor to maximize fluid temperature is the flow rate and the interaction between absorption tube length and fluid type. It also was found that fluid temperature inside the collector was maximized when hydraulic oil was used as the heat transfer fluid and when the tube length was 436 mm.
Analysis, Simulation and Application of SFIT in Microfluidic Systems
Authors: Haddadi Bahareh
Published: April 2015

In this paper we analyze a special type of Inter Digital Transducer (IDT), named Slanted Finger Transducer (SFIT) that can be used in microfluidic applications. Using SFIT in microfluidic technology are progressing during recent years. We will analyze the structure of basic SFIT and then a simulation is performed using a finite element software.
Mapping and modelling helminth infections in ruminants in Europe: experience from GLOWORM
Authors: Rinaldi Laura , Hendrickx Guy , Cringoli Giuseppe , Biggeri Annibale , Ducheyne Els , Catelan Dolores , Morgan Eric , Williams Diana , Charlier Johannes , Von Samson-Himmelstjerna Georg , Vercruysse Jozef
Published: April 2015

Mapping and modelling helminth infections in cattle and sheep in Europe through advanced geospatial research was one of the main task of GLOWORM, a three year project (2012-2014) funded under the European Commission’s (EC) seventh framework programme (FP7). Liver flukes as Fasciola hepatica and gastrointestinal nematodes, such as Haemonchus contortus were chosen for the project since these parasites constitute a major cause of lost productivity in small and large ruminants. The output of the GLOWORM project delivered guidelines for standardized and harmonized cross-sectional surveys of helminth parasites in ruminants allowing the development of updated prevalence maps and multi-scale, spatial models for the European area.
Modelling the spatial distribution of Fasciola hepatica in dairy cattle in Europe
Authors: Ducheyne Els , Charlier Johannes , Vercruysse Jozef , Rinaldi Laura , Biggeri Annibale , Demeler Janina , Brandt Christina , De Waal Theo , Selemetas Nikolaos , Höglund Johan , Kaba Jaroslaw , Kowalczyk Slawomir J. , Hendrickx Guy
Published: April 2015

A harmonized sampling approach in combination with spatial modelling is required to update current knowledge of fasciolosis in dairy cattle in Europe. Within the scope of the EU project GLOWORM, samples from 3,359 randomly selected farms in 849 municipalities in Belgium, Germany, Ireland, Poland and Sweden were collected and their infection status assessed using an indirect bulk tank milk (BTM) enzyme-linked immunosorbent assay (ELISA). Dairy farms were considered exposed when the optical density ratio (ODR) exceeded the 0.3 cut-off. Two ensemble-modelling techniques, Random Forests (RF) and Boosted Regression Trees (BRT), were used to obtain the spatial distribution of the probability of exposure to Fasciola hepatica using remotely sensed environmental variables (1-km spatial resolution) and interpolated values from meteorological stations as predictors. The median ODRs amounted to 0.31, 0.12, 0.54, 0.25 and 0.44 for Belgium, Germany, Ireland, Poland and southern Sweden, respectively. Using the 0.3 threshold, 571 municipalities were categorized as positive and 429 as negative. RF was seen as capable of predicting the spatial distribution of exposure with an area under the receiver operation characteristic (ROC) curve (AUC) of 0.83 (0.96 for BRT). Both models identified rainfall and temperature as the most important factors for probability of exposure. Areas of high and low exposure were identified by both models, with BRT better at discriminating between low-probability and high-probability exposure; this model may therefore be more useful in practise. Given a harmonized sampling strategy, it should be possible to generate robust spatial models for fasciolosis in dairy cattle in Europe to be used as input for temporal models and for the detection of deviations in baseline probability. Further research is required for model output in areas outside the eco-climatic range investigated.