bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Preparation and Surface Properties of Fluorinated Acrylate Hydrophobic Polymer Film
Authors: Chen Jing , Cheng Qian , Chen Shun Quan
Published: February 2015

A new fluorinated acrylate terpolymer hydrophobic polymer was prepared by emulsifier-free inverse microemulsion polymerization using methyl methacrylate (MMA) and hexafluorobutyl acrylate (HFBA) as monomers, and methyl polyethylene glycol methacrylate (MPEGMA) as polymerizable emulsifier. Membrane properties were characterized by means of FT-IR, SEM and Contact Angle Meter. The effect of fluorinated monomer content, water content in the inverse precursor microemulsion on the surface morphologies and hydrophobicity of the polymer film was mainly discussed. Morphological studies of the fluorinated polyacrylate polymers by SEM showed that discrete granular microstructures were obtained from precursor microemulsion with higher water content. On the other hand, smooth and continuous surface morphologies were found with lower water content. Contact angle revealed that the fluorine preferentially enriched at the film-air interface and more hydrophobic that the film-glass interface. The amount of HFBA had significantly effects on the film properties. The water contact angle of the film-air interface increased as the amount of HFBA increased from 0 ml to 4 ml and then remained almost unchangeable. The film formed from the fluorinated polyacrylate polymer with higher water content in the precursor microemulsion exhibited better hydrophobicity in comparison with the film formed from the fluorinated polyacrylate polymer with the lower water content, and it confirmed that rough surface have high water contact angles.
Friction Stir Processing of Cast Iron Using Cermet Tool
Authors: Mizutani Yoshiki , Hosokawa Hiroyuki
Published: February 2015

With the aim of developing a durable tool for friction stir processing (FSP) of cast iron, the durability of a Ti (C,N)-Ni cermet tool has been investigated and compared with that of a WC-Co cemented carbide tool. Results of exposure tests in air revealed that the WC-Co cemented carbide sample oxidized rapidly above 973 K, whereas the cermet material showed little oxidization even after holding at a temperature of 1103 K. When these tools were used for the FSP of cast iron surfaces, it was found that an oxide layer of over 100 μm was generated on the lateral faces of the WC-Co cemented carbide tool after it was used to work a length of 400 mm. In contrast, a thin oxide layer of only 5 μm was generated after the cermet tool worked a length of 2400 mm. Cross sections of the iron casts (FC250) subject to FSP using these tools showed that in a bowl-shaped region approximately 1.5 mm deep the initial pearlite structures changed to martensite structures. The martensite structures in this region had a Vickers hardness of 600 to 800 HV, while that of the initial pearlite structure was about 280 HV.
Improvement of Wet Milled TiC-Feal Alloys
Authors: Shimojima Koji , Hosokawa Hiroyuki , Furushima Ryoichi , Katou Kiyotaka , Matsumoto Akihiro
Published: February 2015

TiC based cermet is a candidate material for alternatives of WC-Co used in tools/dies. Ordinary, Ni and Co, etc. are used as a metal binder of TiC based cermet. They are kinds of rare metals, therefore it is desired that metal binders are also replaced with the ubiquitous materials. FeAl intermetallic alloys are one of candidate materials of alternative rare metal binder made from ubiquitous materials. FeAl is well-known as an extremely resistance material to corrosion under oxidizing atmospheres, sulfidizing atmospheres, and in molten salts. Combination of intermetallic and carbide, the hardness is very high, but it would be brittle. In this work, TiC-FeAl alloys are made by wet milling and pulsed electric current sintering to improve transverse rupture strength while the hardness is kept. We achieved that TiC-40 vol. % (Fe-40 at. % Al) alloy with hardness of 17.7 GPa and T.R.S. of 1.9 GPa.
Application of Orthogonal Experiments Design to Optimize Process Parameters in the Alloy Heat Treatment
Authors: Zhou Shun Yong , Xie Wen Ling , Guo Cui Xia , Wen Yu Hua
Published: February 2015

The heat treatment process parameters are designed by orthogonal test method. Choosing the most important three parameters of the deformation aging parameters, deformation at room temperature, aging temperature and aging time as 3 factors and each factor uses 4 levels. 16 sets of experiments are organized in accordance with orthogonal table to get each factor in order of priority in effecting on the experimental results and the optimal process combination. Through experiments, the optimal process combination agrees with the actual.
Heat Transfer and Solidification Model of Slab Continuous Casting Based on Nail-Shooting Experiments
Authors: Hou An Gui , Min Yi , Liu Cheng Jun , Jiang Mao Fa
Published: February 2015

A heat transfer and solidification model of slab continuous casting process was developed, and the nail-shooting experiments were carried out to verify and improve the prediction accuracy. The comparison between the simulation and the measurements results showed that, there exists difference between the model predicted liquid core length and the calculated liquid core length according to the measurement results of the solidification shell thickness. In the present study, the value of constant a in the heat transfer coefficient calculation formula was corrected through back-calculation, results showed that, the suitable value of a is 31.650, 33.468 and 35.126 when the casting speed is 0.8m·min-1, 0.9m·min-1 and 1.0m·min-1 respectively, which can meet the liquid core length of the measurement results. The developed model built a foundation for the application of dynamic secondary cooling, and dynamic soft reduction.
High-Temperature Corrosion of Carbon Steel in Air, Ar/0.2%SO2, and N2/0.4%H2S Gases
Authors: Abro Muhammad Ali , Lee Dong Bok
Published: February 2015

Hot rolled mild steel was corroded in air, Ar/0.2%SO2 and N2/0.4%H2S gases for 20 and 50 h. The corrosion in air at 800 and 1000°C resulted in the formation of Fe2O3/Fe3O4/FeO layered scales from the surface. The corrosion in Ar/0.2%SO2 gases resulted in the formation of (FeS, Fe2O3, Fe3O4, FeO)-mixed scale at 800°C, and (Fe2O3, Fe3O4, FeO)/FeS layered scale at 1000°C. The corrosion in N2/0.4%H2S gases at 650 and 750°C led to the formation of (Fe2O3, Fe3O4, FeO)/FeS layered scales.
Tensile Properties of Squeeze Cast Mg-Al-Sr Alloy under Applied Pressures
Authors: Fang Li , Hu Henry , Wang Shu Ping
Published: February 2015

The focus of this study is on development of alternative manufacturing processes for potential high temperature magnesium-aluminium-strontium alloys. The effect of external pressure on tensile properties of squeeze cast Mg-Al-Sr alloy was investigated. Four different applied levels, 0, 30, 60 and 90 MPa, were employed to exert on a Mg-6 wt.% Al – 0.5 wt.% Sr alloy during squeeze casting. The results of tensile testing indicate that the ultimate tensile strength (UTS), yield strength (YS) and elongation (Ef) of the squeeze cast Mg-Al-Sr alloy increase with increasing applied pressure level. The microstructural analysis and porosity measurements suggest that the tensile property enhancement resulting from applied pressure should be attributed to microstructure refinement and porosity reduction of the squeeze cast alloy.
Effect of Holding Time on Microstructures of AZ91D Alloy by the Semi-Solid Thixo-Extruded Process
Authors: Zheng Xiao Ping , Ji Ze Sheng , Zhang Wei Wen , Shao Ming
Published: February 2015

The semi-solid thixo-extruded process of AZ91D magnesium alloy with 9 % plastic deformation was investigated. The effect of isothermal time on the thixo-extruded formability of AZ91D magnesium alloy was analyzed. The relationship between isothermal time and microstructure, mechanical property was also researched. The results showed that with increasing the isothermal time from zero to 60 min on 575 °C, the filling distance was increased firstly and then decreased, the solid volume fraction was decreased firstly and then increased, the tensile strength and elongation were also increased firstly and then decreased. However, the increasing isothermal time would lead to decrease of shape factor but the coarsening of particle size. When the isothermal time was 30 min, the solid volume fraction was lowest and the filling distance was greatly increased obviously.
Microstructure and Mechanical Properties of As-Cast and As-Extruded Mg-Gd-Er-Zn-Zr Alloy
Authors: Wen Kai , Du Wen Bo , Liu Ke , Wang Zhao Hui , Li Shu Bo
Published: February 2015

The Microstructure and mechanical properties of as-cast and as-extruded Mg-12Gd-2Er-1Zn-0.6Zr alloy are investigated in the present paper. The microstructure is analyzed by OM, SEM and TEM with SAED, and the mechanical properties are valued by the room temperature tensile test. The result shows that the coarse Mg5(Gd, Er, Zn) phase in the as-cast alloy was broken during hot extrusion process, and it was distributed at the grain boundary along the extrusion direction. The enhancement in mechanical properties of the extruded alloy is mainly ascribed to the refinement of these grains. The sizes of dynamical recrystallized grains are homogeneously, which was about 7 μm. Stacking fault existed in the as-cast alloy, which has a little effect on the dynamic recrystallization because of its tiny thicknesses.
Development and Application of Manganese Cobalt Lithium Compounds in the Field of Lithium Batteries
Authors: Tang Yao , Zhan Zhao Lin , Yu Xiao Hua , Ma Miao , Li Xiao Yu
Published: February 2015

Manganese lithium cobalt compounds have been used in the preparation of lithium battery cathode material because of its excellent electrochemical characteristics and gradually in recent years. This paper introduces the different methods of preparing the compounds, analyzes the structural characteristics of the manganese cobalt lithium compounds and the differences in the electrochemical properties, the end of the article has carried on the forecast to the future development direction of the compound.
Bi-(2, 4-dihydro-2H-3-(4-N-maleimido) phenyl-1,3-benzoxazine) Isopropane: Molecular Structure, Optical Spectrum and Thermodynamic Properties
Authors: Guan Yong Hua , Chen Zi Ran , Xu You Hui
Published: February 2015

A novel substance, bi-(2, 4-dihydro-2H-3-(4-N-maleimido) phenyl-1, 3-benzoxazine) isopropane (BMIPBI), was investigated by density functional theory and calculation at the B3LYP/6-311+G* level for its molecular geometric configuration, infrared spectrum, electronic absorption spectrum and thermodynamic properties. The results demonstrated that, in the stable configuration of a BMIPBI molecule, the two side chains of 2, 4-dihydro-2H-3-(4-N-maleimido) phenyl-1, 3-benzoxazine connecting with both ends of the isopropane were not in the same plane, and the two side chains were rather different in structure. The minimal energy jump of gaseous molecules located at 533 nm, corresponding to π→π* jump of HOMO→LUMO. Along with the increase of the solvent’s polarity, the minimal energy absorption wavelength shifted to blue, mainly originated from changes in the transition properties, corresponding to π→π* jump of HOMO→LUMO+1. At 298.15 K and standard atmospheric pressure, the standard molar formation enthalpy and standard molar formation free energy of formation of the TMIPT molecule was-1212.46 and-532. 94 kJ/mol, respectively.
Co-Effect of AlF3 and MgF2 Coating on the Electrochemical Performance of LiNi1/3Co1/3Mn1/3O2 Cathode Material under High Voltage
Authors: Zhao Fei Fei , Mu Dao Bin , Hou Xiong Xiong , Wang Lei , Ren Yong Huan , Wu Bo Rong
Published: February 2015

AlF3 and MgF2 were applied to modify the surface of the LiNi1/3Co1/3Mn1/3O2 cathode material. The structural and electrochemical properties of the materials were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), charge–discharge tests and electrochemical impedance spectra (EIS). The results show that the 1 wt.% AlF3 and 1 wt.% MgF2 coated LiNi1/3Co1/3Mn1/3O2 (NCM333) cathode material exhibits an optimized electrochemical performance. It presents an initial capacity of 207.2mAh/g and 169.1mAh/g at 0.2C between 2.8V and 4.7V after charge-discharge 65 cycles. The rate performance is also enhanced because the coating decreases the interface charge transfer impedance.
Novel Sorbents and their Sorptive Properties for Mercury Emissions Control of Coal-Fired Flue Gas
Authors: Huang Na , Zhu Yan Bin , Meng Dan Jie
Published: February 2015

Mercury is a striking pollutant and mercury emissions from coal-fired power plants are under environmental regulation. The primary objective of mercury abatement in coal-fired power plants is to remove elemental mercury. Sorbent injection is one of the major commercially available technologies for mercury control from coal fired power plants and activated carbon is the most commonly employed sorbent. Modified activated carbons have been found to exhibit high mercury emission reduction efficiency. Noble metal and metal oxides also showed excellent mercury adsorption capacity. Fly ash, a waste product from coal-fired solid wastes, may be an excellent adsorbent owing to its low cost and abundance. There is no consistent evidence for the adsorption mechanism of mercury on modified activated carbon; a popular view is that the sorption mechanism is combination of physisorption and chemisorption.
The Interactions with Proton-Donor Solvents and Stability of some Borondipyrrinates
Authors: Kuznetsova Rimma T. , Aksenova Yulia V. , Mayer Georgii V. , Antina E.V.
Published: February 2015

The constants of acid-base equilibrium were estimated with spectroscopic method at the ground (S0) and at the fluorescent (S1fl) states. The constants of acid-base equilibrium for Franck-Condon excited states (S1F-C) were estimated from spectral shifts for basic and acid forms. This results are compared with quantum yields of photostability of complexes in neutral solvents. The mechanisms of complexes protonation are discussed dependence from the structure of ligands.
Study on Melamine Formaldehyde/Polyvinyl Alcohol Blend Fiber by Electrospinning
Authors: Li Lu Lu , Kang Yong Qiang , Yang Yan Gong , Cong Ri Min , Jia Zhao
Published: February 2015

Melamine formaldehyde (MF) resin and its derivatives are always considered to be excellent flame retardant material, which has wide application in the flame retardant fabric, high temperature insulating filter materials, etc. However, less research on electro-spinning of melamine fiber has been reported, recently. In the study, the molar ratio, condensation polymerization temperature of formaldehyde and melamine, and the law of effect in different solid content ratio of melamine formaldehyde/polyvinyl alcohol on the electro-spinning were studied. The results showed that the best conditions for spinning were that formaldehyde and melamine molar ratio was 1:1.7, the reaction temperature was 80°C, and the MF-PVA blending solid content ratio was 1:1, meanwhile the morphology of Electron microscopy indicated the good uniformity of the fiber. The fiber presents good flame retardant property in conditions of MF-PVA blending solution viscosity 155mPa ́s, limit oxygen index 33.2%.
Synthesis of Polypropylene Strong Acid Cationic Exchange Fiber
Authors: Chen Wei
Published: February 2015

A novel polypropylene strong acid cationic exchange fiber (SACEF) was prepared by sulphonation reaction of polypropylene graft styrene (PP-g-St) fiber, using 1,2-dichloroethane as swelling agent. Factors effected the adsorption capacity of SACEF synthesized from PP-g-St fiber, such as swelling time, grafting degree of PP-g-St, liquor ratio (mass of fiber vs. volume of the reaction reagent), reaction temperature, and sulfuric acid concentration were investigated. The results showed that the average adsorption capacity of SACEF was 4.42 mmol·g-1.
The Performance Study of Waterborne Damping Coating
Authors: Wang Xiao , Hou Pei Min , Xu Yuan Hao , Lei Jian
Published: February 2015

In this paper, waterborne damping coating with excellent performance was prepared by self-made acrylic resin, and its physical and mechanical properties, chemical resistance, and damping properties (damping factor) were studied.
Modification of Unsaturated Polyester Resin by Methyl-α-Eleostearate-Maleic Anhydride Adduct
Authors: Zhou Jin Hua , Li Ni , Ma Wen Jie , Yang Jing , Sun Han Zhou
Published: February 2015

Unsaturated polyester resin (UPR) is one of the film-forming resins commonly used for preparation of coatings. However, the general type UPR has some disadvantages which limit its application such as poor water resistance, solvent resistance, heat resistance and mechanical properties. To improve common UPR’s comprehensive performance, methyl-α-eleostearate-maleic anhydride adduct (MEMAA), a derivative from Tung oil, was prepared and introduced into UPR system to form MEMAA modified UPR (M-UPR). Influences of MEMAA’s dosage in M-UPR on water and toluene absorption and tensile strength of M-UPR were investigated. The thermal property and morphology of M-UPR were also studied by TGA and SEM, respectively. Experimental results show that the water resistance, solvent resistance and tensile strength of UPR have been improved a lot and the heat resistance of UPR also has a certain degree of improvement after UPR’ being modified by MEMAA. Compared with the common UPR film, when the dosage of MEMAA is 9% of UPR’s mass, the water absorption, toluene absorption of M-UPR film are decreased by 21.0% and 18.6%, respectively, and whereas, the tensile strength and thermal decomposition temperature of UPR film are increases by 14% and 20 oC.
Hyperbranched Triazine Compounds Grafted Carbon Nanotubes for Improved Tribological Performance of Bismaleimides Composites
Authors: Nie Yi Han , Yan Hong Xia , Li Ting Ting
Published: February 2015

A kind of high-performance bismaleimides composite has been fabricated using carbon nanotubes as filler, in which the carbon nanotubes was grafted by hyperbranched triazine compound (HPTC-CNTs). The investigation of properties the composites show that the addition of the appropriate content of HPTC-CNTs can enhance the tribological properties. It’s worth noting that when the content of HPTC-CNTs is 0.6 wt. %, the frictional coefficient and the wear rate decrease by 29.5% and 91.8% respectively compared to neat BMI. Scanning electron microscope（SEM）reveals that wear mechanism of neat BMI is mainly fatigue wear, but it turns adhesive mainly wear after the incorporation of HPTC-CNTs. The main reason can be the good dispersability and compatibility of HPTC-CNTs in the bismaleimides matrix.
New Biomimetic Hybrid Nanocomposites for early Fixation Prostheses
Authors: Aversa Raffaella , Sorrentino Roberto , Apicella Antonio
Published: February 2015

The research develops and tests new hybrid biomimetic materials that work as mechanically stimulating "scaffolds" to promote early regeneration in implanted bone healing phases. A biomimetic nanostructured osteoconductive material coated apparatus is presented. Bioinspired approaches to materials and templated growth of hybrid networks using self-assembled hybrid organic-inorganic interfaces is finalized to extend the use of hybrids in the medical field. Combined in vivo, in vitro and computer aided simulations have been carried out. A new experimental methodology for the identification of design criteria for new innovative prosthetic implant systems is presented. The new implant design minimizes the invasiveness of treatments while improving implant functional integration. A new bioactive ceramo-polymeric hybrid material was used to modify odontostomatological Titanium implants in order to promote early fixation, biomechanical stimulation for improved scaffold mineralization and ossification. It is a hybrid ceramo-polymeric nanocomposites based on Hydroxyl-Ethyl-Methacrylate polymer (pHEMA) filled with nanosilica particles that have shown biomimetic characteristics. This material swells in presence of aqueous physiological solution leading to the achievement of two biomechanical functions: prosthesis early fixation after and bone growth stimulation. Such multidisciplinary approach explores novel ideas in modelling, design and fabrication of new nanostructured biomaterials with enhanced functionality and improved interaction with OB cells
Synthesis and Photophysical Property of Polyion Complex Micelle Incorporating Phthalocyanine Zinc(II) Bearing Benzyl Ether Dendritic Substituents with Nitro-Terminal Group
Authors: Zhu Xiao Dong , Chen Zhen Zhen , Wu Ke Qin , Wen Jun Ri , Wang Xiong Wei , Peng Yi Ru
Published: February 2015

A new phthalocyanine Zinc(II) bearing benzyl ether dendritic substituents with nitro-terminal group: tetra-{3,5-[di-(4-nitro benzyloxy) benzyloxy]} Phthalocyanine Zinc(II) (ZnPc(NO2)8), was synthesis and characterized by IR, 1HNMR, MALDI-TOF-MS and UV/Vis. UV/Vis spectra of ZnPc(NO2)8 exhibited characteristic absorption peaks at 290, 350 and 680 nm, and fluorescence emission peak was at 692 nm with a quantum yield at 0.20 in dimethylsulfoxide (DMSO). The polymeric nanoparticle ZnPc(NO2)8@MPEG-PLGA was formed between the amphiphilic block copolymer poly(ethylene glycol)-polylactic and polyglyctic acids (PEG-PLGA) and ZnPc(NO2)8, ZnPc(NO2)8@MPEG-PLGA formed a core-shell-type nanoparticle with diameter about 70 nm. UV/Vis spectra and fluorescence emission spectra of ZnPc(NO2)8@MPEG-PLGA were obviously lower than that of free ZnPc(NO2)8 in buffer solution, and with varying degrees of redshift. ZnPc(NO2)8@MPEG-PLGA would be a promising third-generation photosensitizer for PDT.
The Study of the Effect of Concentrated Growth Factors (CGF) on the New Bone Regeneration of Immediate Implant
Authors: Yang Li Ming , Liu Zhen Zhe , Chen Shu Ping , Xie Chun , Wu Bin
Published: February 2015

Objective: To study the effect of concentrated growth factor (CGF) on reducing bone resorption in immediate implant. Methods: 20 immediate implant patients were divided into two groups, each group included 10 patients who were treated by adding CGF or Bio-oss to the gap of implant-bone, respectively; the labial new bone regeneration was evaluated in postoperative 1 years using cone beam CT. Results: The buccal bone width variation of the CGF group was 0.85±0.25mm, and the Bio-oss group was 0.35±0.25mm (p <0.05). Conclusion: The CGF has no significant role in promoting new bone regeneration when was used alone in the gap of implant - bone in immediate implant
Formulation and Technology Study on the Taste Masking Granules
Authors: Zhang Ying Qing , Gao Qun , Luo Wei , Zou Ming , Yuan Wen Feng , Mi Zhi Yuan
Published: February 2015

Objective: To investigate the formulation and technology for taste-masking granules. Methods: Clarithromycin was used as a model active pharmaceutical ingredient with bitter taste. Four preparation processes were compared, which were gelatin mono-condensation microcapsule method, calcium alginate microcapsule method, gelatin microsphere method and resin matrix granulation method. With taste masking effect and dissolution rate as evaluation indexes, the optimal preparation technology was studied. The orthogonal experiment was used to investigate the optimal formulation. Results: Clarithromycin granules prepared by the resin matrix granulation method had good taste masking effects and suitable dissolution rate. The optimal formulation was following: polyacrylic acid resin IV 0.85 g, PEG4000 0.30 g, sodium bicarbonate 0.10 g. The prepared clarithromycin granules have good taste masking effect and its dissolution in 45 min can reach 80.5%. Conclusion: The optimal formulation and technology can satisfy the request for taste masking and dissolution rate of clarithromycin granules.
Adsorption of 2,4-Dichlorophenol and Rhodamine-B from Aqueous Solutions onto Activated Carbon Derived from Phragmites Australis
Authors: Chen Su Hong , Zhang Jian , Han Zhi Jun , Zhang Cheng Lu , Yue Qin Yan
Published: February 2015

This study investigates the potential use of activated carbon prepared from Phragmites Australis for the removal of 2,4-dichlorophenol (DCP) and Rhodamine-B (RB) from aqueous solutions. P. Australis activated carbon (PAAC), a new adsorbent, was prepared from P. Australis by H3PO4 activation. Batch adsorption studies were conducted to evaluate the effect of various parameters such as pH, adsorbent dose, contact time and initial 2,4-DCP and RB concentration. Accordingly, the activated carbon developed in this study is effective and practical for utilization in wastewater treatment for 2,4-DCP and RB removal.
Evaluation of the Tensile Modulus of Elasticity in Parallel Direction to the Grain for Eucalyptus grandis Wood Specie
Authors: Christoforo André Luis , Rocco Lahr Francisco Antonio , Valarelli Ivaldo D. , Battistelle Rosane A.G. , Branco Luiz A. Melgaço N. , Chahud Eduardo , Hallak Panzera Túlio
Published: February 2015

This research aimed to present an alternative methodology to determine the tensile modulus of elasticity based on the least squares method, allowing multiple uses of load and displacements values obtained from the experiment, giving greater reliability in the calculation of timber stiffness. Were used twelve specimens of Eucalyptus grandis wood species, tested in tensile parallel to the grain according to the assumptions of the Brazilian standard ABNT NBR 7190:1997. The modulus of elasticity obtained from the proposed calculation approaches were compared with the elastic moduli obtained from Brazilian standard recommendations. Results of analyzes of variance (Kruskal-Wallis) showed statistical equivalence between the modulus of elasticity obtained for both forms of calculation. However, considering the non-homogeneity of wood, to generalize the conclusions, it is necessary new set tests involving all strength classes indicate by NBR 7190:1997.
Anatomical Description of Guanandi Wood, from Pure Plantation, and its Use as Building Material
Authors: Barreiros Ricardo Marques , Amaral Simone Simões , de Matos Carlos Alberto Oliveira , Costa Alex Siqueira
Published: February 2015

This work aims to contribute with information about the structural wood anatomical description Calophyllum brasiliense Camb.. The study was conducted in an area of 1350 m2, with spacing 4.0 m x 2.5 m, in the Paraná State, Brazil. Five specimens of C. brasiliense, with 13 years of age, were collected. For the macro and microscopic anatomical analyses were obtained disks to 0%, 25% and 50% of the commercial height of the trunk. The anatomical structure of wood of C. brasiliense, from pure plantation, was similar to existing literature for native forests. The results showed that the cultivation of trees of Guanandi, from pure plantation, can be a sustainable alternative in obtaining building material.
Influence of Time Evolution in the Modulus of Elasticity of Concrete Reinforced by Carbon Fibers
Authors: Couto Aguiar Letícia , Branco Luiz A. Melgaço N. , Chahud Eduardo , Rocco Lahr Francisco Antonio , Christoforo André L. , Battistelle Rosane A.G. , Hallak Panzera Tulio
Published: February 2015

The modulus of elasticity is an important property for the behavior analysis of concrete structures. This research evaluated the strain difference between concrete specimens with and without the application of laminate carbon fiber composites as well as the variation time, in months, of the axial strength compression and modulus of elasticity. Through the experimental results, it is concluded that increases in compressive strength and modulus of elasticity are more significant in the specimens without reinforcement.
Post-Fire Study of Strength and Stiffness of a Wooden Roof Structure
Authors: Morales Elen Aparecida Martines , Soares Galdino Danilo , Cortez-Barbosa Juliana , de Campos Cristiane Inácio , de Araujo Victor Almeida , Rocco Lahr Francisco Antonio , Christoforo André Luis , da Silva Sérgio Augusto Mello
Published: February 2015

The characteristics of the behavior of building materials against the fire could realize a preponderant role in the result of an eventual burning situation, difficulting or contributing to reach a critical stage. The present study evaluated the mechanical properties in compression parallel to grain of five pieces of wood from the roof structure of a residence undergo the fire in the rural area of Itapeva/SP. The roof structure was built 25 years ago using wooden beams of the species Guarucaia (Peltophorum vogelianum), where the specimens were obtained. The objective of this work was to realize a case study about strength and stiffness in parallel compression to wood grain in a roof structure of a house located in Itapeva/SP, according to its level of thermal degradation, upon the occurrence of a real fire. In general, despite the many variables involved, the results based on woods of a real fire shown are consistent with the fire simulations provided by the literature.
Influence of the Number of Load Cycles to Obtain the Stiffness Properties of Angico Preto (Anadenanthera macrocarpa) Wood Specie
Authors: Chahud Eduardo , Branco Luiz A. Melgaço N. , Rocco Lahr Francisco A. , Christoforo André L. , Battistelle Rosane A.G. , Valarelli Ivaldo D.
Published: February 2015

The tests used to obtain the stiffness properties of wood are made with two loading cycles, as defined by the Brazilian standard ABNT NBR 7190 (Design of Timber Structures). However, the possibility of reducing the number of cycles allows decrease the operating time of the machine, resulting in reduced spending on electricity used during the tests. This research aimed to investigate, with the aid of the analysis of variance (ANOVA), the influence of the use of three load cycles to obtain the modulus of elasticity in compression parallel to grain (Ec0), in tensile parallel to the grain (Et0), in bending (Em) and in compression perpendicular to the grain (Ec90) of Angico Preto (Anadenanthera macrocarpa) wood specie. For the number of cycles and stiffness were manufactured 12 samples, totaling 144 specimens. The results of the ANOVA revealed statistical equivalence between the stiffness properties for both load cycle numbers evaluated, indicating that it is possible to carry out the tests with a single charge cycle, allowing savings in time and energy in the operation of the equipment.
Particleboard Manufactured with Bamboo and Coconut Fibers in Different Ratios of Adhesive
Authors: Dinhane Fernanda Christiane Rossetto , de Araújo Isabela Imakawa , Valarelli Ivaldo de Domenico , Bueno Marcus Antonio Pereira , Ferreira Bruno Santos , de Campos Cristiane Inácio
Published: February 2015

This research aimed to develop and evaluation the mechanical properties of a particleboard produced with bamboo particles and coconut fiber in three different experimental conditions. The panels were manufactured with castor oil based polyurethane bi-component resin in three different ratios of the adhesive components (pre-polymer and polyol). Mechanical characterization was conducted to determine modulus of elasticity (MOE) and modulus of rupture (MOR) in static bending. For the static bending test the better values were to the experimental condition 2, which relate de proportion of 1:1.5 of pre-polymer and polyol, respectively. This best solution is to reduce the amount of pre-polymer in the formulation of the adhesive, due to decreased of use of chemicals most polluting.
Moisture Content and its Influence on the Roughness and Noise Emission during Wood Machining
Authors: Pinheiro Cleverson , de Sampaio Alves Manoel Cléber , Simões Amaral Simone
Published: February 2015

Numerous factors influencing the surface quality of wood after machining, among them we highlight the machining parameters and the properties of the wood. In the analysis of the influence of these factors on machining and in determining the quality measurement systems are used to obtain surface characteristics, these systems are divided into methods of contact and non-contact. The method for mechanical contact performed with the aid of the surface roughness tester is the most valued in the measurement of roughness of wood, however, aiming at a greater agility in these measurements, there is a need to seek alternatives for evaluation of surface quality, and one of these options is to use the forms of indirect measurements of this quality, as for example, the use of noise emission during the machining process. With this, the aim was to analyze the influence of the moisture content of the wood, at different levels, on surface quality of the species Pinus elliottii, determined by the method of mechanical probing move and relate this roughness with the sound emission issued for each class of humidity, during machining. The planning of experiments and statistical analyses were performed with the help of Taguchi method. The specimens were conditioned in greenhouses climatizadoras automatics for obtaining three classes of humidity. Machining tests of wooden pieces were performed on a machining center specific for this type of material. The roughness values were measured by a roughness verifier and the noise emission values were measured by for a measurer sound pressure level. Statistically significant differences were observed, the significance level of 10 %, on roughness and noise emission between the three levels of moisture. It was observed that with the increase in the moisture content occurred an increase of roughness and a reduction in noise emission. Monitoring of surface quality through noise level is an interesting alternative to the method of mechanical contact.
Analysis on Causes of Corrosion in the Sleeve Joint of Certain Offshore Pipeline System
Authors: Wang Hong , Liu Xian He
Published: February 2015

Leakage was found in certain oilfield offshore pipeline system and investigation results showed that the cause of the leak was corrosion perforation in the sleeve joints of pipeline system. In order to avoid the leak occurring again, it was necessary to analyze corrosion mechanism of the sleeve joints. Macro and micro analyze, test on physical and chemical properties and microstructure, XRD analysis on corrosion products was accomplished on the sleeve joints. Results obtained from analysis and test show that corrosion was stronger because there are some CO2 and H2S in the pipeline together. Corrosion perforation was brought by flow velocity suddenly increase and turbulent flow and flow field action.
Structural Optimization of Laminated Glass Plate Using Discrete Element Method
Authors: Sakai Shinobu , Maenaka Kensuke , Yamazaki Koetsu
Published: February 2015

Laminated glass is widely used to enhance structural functions. The impact fracture behavior of laminated glass is more complicated than that of single glass, because of the combined influences of the large deformation and delamination strengths. In this study, the impact fracture behavior of a laminated glass plate intended for the outside surface of a modern building has been studied by numerical simulations and experiments. This fracture simulation was calculated using a Discrete Element Method (DEM) based on non-continuum mechanics. The laminated glass structures have been optimized for attaining maximum durability against impact fracture based on the response surface method. In the optimum problem, the tensile strength of the interlayer and the adhesive strength between two pieces of glass and the interlayer are taken as the design variables. From the results of the optimization, it has been observed that the laminated glass difficult to break in the case that the tensile strength was high and that the adhesive strength was a little light. The penetration performance of an optimized laminated glass plate was noticeably better in comparison with a commercial laminated glass plate.
Study on Carbocoal as Microwave Absorber in Microwave Field
Authors: Liu Song , Zhang Ming Xu , Xia Hao
Published: February 2015

The present paper decribed the effects of carbocoal on temperature rising characteristic during coal pyrolysis at different temperature in microwave field. Different mixture rate of carbocoal with coal and different final temperature on coal pyrolysis tempereature rising characteristics were studied in the work. The results indicate: Coal is a poorly microwave absorbing material. Because carbocoal can be fast heated in microwave field, so it can be used as additive for coal pyrolysis. Carbocoal otained from different pyrolysis temperature have different heating rate, along with the increase of carbocoal pyrolysis temperature, carbocoal heating rate increases in microwave field. Using carbocoal as microwave absorbent for coal rapid pyrolysis in microwave field is feasible.
Research on Performance of Drilling Carbon Fiber Reinforced Plastics with Diamond Coated Special Drill
Authors: Yang Xiao Fan , Li You Sheng , Xu Zhi Long , Liu Ju Dong , Wu Bi Jin
Published: February 2015

The carbide cemented special drills with TiAlCrN/TiSiN coating and diamond coating respectively were selected to drilling on carbon fiber reinforced plastics (CFRP) for a contrast test in this paper. The drilling force , drilling exit surface quality and tool wear were analyzed separately to research the performance characteristics of the two kinds of special drills with different coating. The results show that: under the same cutting conditions, the thrust force of the special drill with diamond coating is smaller than that of the TiAlCrN/TiSiN coating, and the tool life is extended by 2 times at the same time. The diamond coated special drill can improve the drilling surface quality, it is more suitable for drilling CFRP.
The Process Optimization of Cast Copper Stave Based on ProCAST
Authors: Lu Xian Zhong , Wan Xu Wei , Fan Xiao Ming , Wang Zhi
Published: February 2015

According to the structure of cast copper cooling stave, two kinds of different pouring systems were designed, and the casting process numerical simulations were conducted with ProCAST software in order to project the foundry defects. Then adopting the process optimization based on the preliminary simulated results and determined the final casting technique of cast copper cooling stave. The results of trial production show that the cast copper cooling stave basically meets the requirements of technology.
Shear Stress Discontinuities in Adhesive Joints
Authors: He Xiao Cong
Published: February 2015

This paper deals with the stress discontinuities in shear stress distribution of adhesive joints. The three-dimensional finite element analysis (FEA) software was used to model the joints and predict the shear stress distribution along the whole beam. The FEA results indicated that there are stress discontinuities existing in the shear stress distribution within adhesive layer and adherends at the lower interface and the upper interface of the boded section. The numerical values of the shear stress concentration at key locations of the joints and the stress concentration ratio are discussed.
Effect of Adhesive Behavior on Normal Stress Distributions in the Single-Lap Adhesive Joints
Authors: He Xiao Cong
Published: February 2015

The effect of adhesives behavior on the normal stress distributions of single-lap adhesive joints is investigated using the three-dimensional finite element technique. Numerical examples are provided to show the influence on the normal stresses of the joints using adhesives of different characteristics which encompass the entire spectrum of elastic stiffness behaviour. finite element analysis solutions of the normal stress distributions in the adhesive layer have been obtained for four typical characteristics of adhesives. The results indicate that Young’s modulus and Poisson’s ratios of adhesives strongly affect the normal stress distributions of the joints.
Research Concerning the Influence of Contact Tip-to-Work Distance (CTWD) on Penetration, Bead Height, Bead Width - Study Case GMAW Cladding
Authors: Cicic Dumitru Titi , Rontescu C. , Amza Cătălin Gheorghe , Semenescu Augustin
Published: February 2015

This paper presents the research results regarding the dependence between CTWD and penetration, bead height and bead width during GMAW cladding.
The Influence of the Welding Current Polarity on the Geometric Configuration of the Bead
Authors: Rontescu C. , Cicic Dumitru Titi , Iacobescu Gabriel , Amza Gheorghe Cătălin
Published: February 2015

Various types of shielding gases mixes are used for the industrial GMAW applications. The use of the direct current welding process with reverse or direct polarity influences the geometric characteristics of the beads as well as process dilution. In certain situations, such as weld deposits, the penetration should be as shallow as possible and the heat affected zone of the bead should be reduced. The paper presents the experimental procedure, the obtained results and the conclusions concerning the influence of polarity on the shape and geometry of the welding beam, while using various shielding gases and various welding parameters and by changing polarities.
The Dispersion of MWCNTS in Acetone Solution of SAN
Authors: Ling Xin Long , Xie Ling Jiao , Zou Li Ming , Wei Yi Zhe
Published: February 2015

MWCNTs were dispersed in acetone solution of styrene-acrylonitrile copolymer (SAN). Four factors which had effect on the average particle size, including the ratio of MWCNTs to SAN, the mass percent of MWCNTs, the ultrasonic power and the ultrasonic time, were studied. The optimal dispersion conditions of MWCNTs in acetone solution of SAN were the ratio of MWCNTs to SAN 1:3, the mass percent of MWCNTs 0.25%, the ultrasonic power 100%, and the ultrasonic time 30 min.
Simulation of Drying Hevea brasiliensis Wood
Authors: de Conti Cláudio , de Conti Andrea Cressoni , Gava Maristela , dalla Valentina Luiz Oliveira Veriano , Prates Glaucia Aparecida
Published: February 2015

The Simpson model proposes that the rate of wood drying is directly proportional to average moisture content. In this work was done the fitting and the reproduction of drying curve for Heveabrasiliensis wood through of Simpson model and the chi-square statistical method. The curves were obtained by drying 108 specimens Heveabrasiliensis wood with size 10 mm x 20 mm x 100 mm that were drying in a laboratory kiln. The drying control was performed through gradual temperature increase in order to minimize the errors arising due the drastic loss of moisture by wood. The gravimetric method was used to evaluate the drying process, the specimens have theirs mass measured every 6 hours until the timber reached the theoretical anhydrous state. The drying curve of rubber wood obtained here can be used to estimate the drying time of this species for different kiln temperature settings.
The Influence of Welding Parameters on Heat Transfer Efficiency of Hybrid Pulsed Nd: YAG/GTAW Welding
Authors: Xie Miao Xia , Zhang Lin Jie
Published: February 2015

In this work, effects of major welding parameters, such as laser power, defocus distance of laser beam, inter-heat sources distance and welding speed, on weld geometry were investigated for pulsed Nd:YAG laser/GTAW hybrid welding of 304 stainless steel. Heat transfer efficiency of pulsed Nd:YAG laser/GTAW hybrid welding process was quantitativly analyzed based on rosenthal equation. Furthermore, melting efficiency was determined from the measured welding seams cross section area.
Simulation of Temperature Field in the Solidification Process of Cast
Authors: Yuan Xun Feng , Hu Rui Xia , Li Ying , Zhou Ying , Li Lei , Wei Lei
Published: February 2015

The direct difference method is used for solving the heat conduction equation, and simulate the solidification process of T-type cast. The effect of the thermal resistance at cast/mold on distribution of temperature and the solidification rate of corner region is studied. The results show that during the solidification process of T-type, the riser region first solidified, followed by the right half, finally the solidified part was around the corner. With the decrease of the thermal resistance at cast/mold, the temperature of the corner area decreased more quickly and the solidification rate increased. In the actual design process, the material with the good thermal conductivity should be selected for the cast mold to accelerate the solidification rate of the corner region, so the solidification rate of the corner and riser region tend towards harmony, which reducing the formation of various types of defects, and the quality and mechanical properties of the casts were improved.
Study on the Promotion Effect of Microwave-Metal Discharge on the Microwave Pyrolysis of Electronic Waste
Authors: Sun Jing , Wang Wen Long , Ma Chun Yuan , Yue Qin Yan
Published: February 2015

This paper discussed the role of microwave-metal discharge on the microwave induced pyrolysis of electronic waste. Two kinds of waste printed circuit boards (WPCB) were selected as the representatives of electronic waste and their pyrolysis processes under both conventional and microwave heating schemes were studied comparatively to reveal the effect of metal discharge. The copper-clad laminated printed circuit board (PCB) is deficient in absorbing microwaves, leading to inefficient microwave pyrolysis of this kind of electronic waste. The discharge caused by introducing metalliferous materials with metal tips or corners in the electromagnetic fields can result in high local temperature and complement the deficiency in the microwave absorption. The pyrolytic process can be promoted greatly by the thermal effect of discharge in the beginning and the enhanced consequent wave-absorption capacity as a result of the generated pyrolytic coke.
Deformation Behavior Analysis of Harmonic Structure Materials by Multi-Scale Finite Element Analysis
Authors: Yu Han , Watanabe Ikumu , Ameyama Kei
Published: February 2015

The harmonic structure materials consist of coarse-grained areas enclosed in a three-dimensional continuously connected network of ultrafine-grained area. The concept of harmonic structure design has been successfully applied to a variety of pure metals and alloys by mechanical milling (MM) and subsequent powder metallurgy (PM) process. In harmonic structure material, core region with coarse grains maintains a high ductility while the shell region with ultrafine grains contributes for a higher strength. Therefore, the material with harmonic structure design can achieve both strength and ductility simultaneously. In this research, the SUS304L grade stainless steel has been used as a model material to understand and validate the response of the harmonic structure materials towards the applied external loads. The numerical simulation of multi-scale FEA (Finite Element Analysis) was carried out, and it was confirmed that microscopic deformation and the macroscopic tensile strength can be characterized by the present approach.
Finite Element Analysis of Anchorage Structure for FRP Tendon
Authors: Li Shi Quan , Chen Bei , Xie Gui Hua
Published: February 2015

FEM is important research method for the design of the new structural, which with practicality and repeatability. FEM model of the anchorage is established by ANSYS. Extracting and fitting the radial stress distribution curve of the surface of the metal tube clamping. The impact of clip inclination, cone angle difference and pretension to radial stress are analyzed.