bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Test Materials with the Relationship between Growth and Development Characteristics and Temperature and Relative Humidity of Jacaranda mimosifolia
Authors: Sun Ying , Li Fan , Shi Jin An
Published: August 2013

Jacaranda mimosifolia of 55-year-old in Sichuan Neijiang was selected as test material. Through the observation of its growth and development by 2011 and the analysis of temperature and relative humidity, this study discussed its basic law of growth and development and the relationship between temperature and RH factor. By analysis of variance, there was no significant difference in monthly average temperature and RH between 2011 and the climate in Neijiang, the temperature and RH of 2011 could reflect the situation of Neijiang regional climatic. The results showed that the average annual growth of J. mimosifolia new shoot was 32.4cm and the average thickness was 11.2mm, and appeared thrice sprouting and twice flowering phenomenon per year. Combined the characteristics of growth and development of J. mimosifolia, the length and thickness of spring shoot, summer shoot and autumn shoot were both extremely different (P<0.01), and two florescence appeared in Spring and Autumn when the temperature was not different significantly. Therefore, temperature played an apparently predominant role in its growth and development.
Study on Engineering Materials with Optimization Design of Pile-Anchor Support for Foundation Pit Based on Uniform Test and SVM Response Surface
Authors: Ding Wen Yun , Zhao Dang Shu , Cao Jing , Liu Hai Ming
Published: August 2013

foundation pit, pile-anchor support, optimization design, uniform test, SVM response surface
Improving the Biodegradability of Polylactic Acid at Alcaligenes Faecalis and Staphylococcus Aureus Using the Optimization Method
Authors: Wang Shu Wen , Su Te Li
Published: August 2013

The degradation of polylactic acid (PLA) can be divided into the hydrolysis, the degradation and metabolism. The hydrolysis reaction is caused by chain breakdown of the polymers of polylactic acid, resulting in the degradation of polylactic acid. Therefore, this study aims to improve the hydrolysis rate of PLA at the early stage of degradation process and then it increases the degradation rate of the PLA in the natural environment. We employed Taguchi method for parameter design of PLA hydrolysis, focusing on the control factors that affect the conditions of the hydrolysis rate of PLA, such as temperature, bacteria, ventilation degree, and nutrients and we also used orthogonal array to precede experiments, in conjunction with analysis of variance (ANOVA) to identify significant factors and optimal hydrolysis conditions for PLA. By analysis of variance, we know that temperature and bacteria as significant factors, and the factor of temperature contributed 96.882%. Finally, we employed confirmation Experiment to verify the reproducibility of the experiments. Our results have shown that the best condition of PLA hydrolysis rate experience with the reliability of its representatives are in compliance with the 95% of confidence interval, CI, which indicates the reliability of our study.
NOx-Sensing Characteristics of Sensor with ZnFe2O4 Sensing Electrode
Authors: Wu Yin Lin , Zhao Hai Yan , Wang Qing Hui , Wang Ling
Published: August 2013

Electrochemical sensors based on tubular yttria-stabilized zerconia (YSZ) with the spinel-type oxide as a sensing-electrode (SE), which is prepared by sol-gel method, were fabricated and examined for NO2 detection in the temperature range 450~500°C. The results show that ZnFe2O4, shows extreme sensitivity to NO2. The EMF varies linearly as a function of the concentration of NO2 (0 ~ 463 ppm) at 500 °C.
Study on Mine Materials with Exploring for Future Development Direction of Resources Crisis on Mines
Authors: Bao Yu Xue
Published: August 2013

The resources crisis mines is a necessary stage of mining enterprise development, the mine materials with exploring for future development direction of resources crisis on mines concerning the rise and fall of the country, The scientific analysis and beneficial exploration for future development direction of the resources crisis mines, which can provide reference for the future development of resources crisis mines.
Seismic Vulnerability Assessment of Existing Precast Industrial Buildings
Authors: Valente Marco
Published: August 2013

This study was developed within a research project concerning the seismic vulnerability assessment of precast industrial buildings built in Italy in the 1970s without earthquake-resistant provisions. Two reference precast buildings with beam-to-column connections based on neoprene-concrete friction strength were considered. Accurate numerical models of the existing buildings were developed and nonlinear dynamic time-history analyses with different seismic intensity levels were carried out in order to identify the main causes of structural collapse. The maximum values of the demand-to-capacity ratio in terms of chord rotation were computed for the columns of the investigated precast buildings. The capacity was larger than the demand, even in case of high levels of seismic excitation. Numerical results showed that existing precast industrial buildings can collapse due to beam-to-column connection failure for loss of support, confirming real events observed during recent earthquakes. The friction resistance was exceeded under moderate-to-severe seismic actions at the corner columns where the static vertical load was lower. Numerical analyses highlighted the detrimental effects of the vertical component of the seismic action on the likelihood of the occurrence of beam-to-column connection failure due to loss of support.
The Construction Technique of the Beam Slab Structure being Filled Large-Span Prestressed Lightweight Materials
Authors: Yuan Jun Li
Published: August 2013

Abstract: With the rapid development of Chinese economy, more and more requirements of large public buildings, large space and has more functions, the engineering design, construction and bring many technical problems, in order to solve the technical problem, the construction of scientific research departments continue to research and development of new materials, new technology, new methods of construction, city of Puyang stadium the tennis project 44M*24M large span structure, adopts the ‘made of light material combined unit filled prestressed concrete cast-in-situ slab’ structure technology, solves the light, save steel, concrete, reduces the structure thickness, good economic practicability.
Impact of the Chemical Injection Method on the Dispersion of the Injected Agents in History Masonry of Construction Industry
Authors: Nenadálová Šárka , Balík Lukáš , Kolisko Jiří
Published: August 2013

Chemical injection of masonry is a very extensively-used method for providing supplemental water-proofing of historic masonry. Like all branches of the construction industry, chemical injection of masonry is under big pressure to achieve greater performance and speed together with maximum efficiency. Current norms and standards permit both pressure injection and non-pressure injection. Are these methods comparable in efficiency, or should we expect differing effects A pilot experiment on model masonry pillars has been carried out at the Klokner Institute. This paper summarises the results and findings of our experiments.
Study on Simulation of Deep Roadway Support Effect Based on Mechanics Analysis and Material Properties
Authors: Chen Gang , Sun Guang Yi , Wang Qiong
Published: August 2013

Some engineering damage often appears in deep mining. In order to solve that engineering problems, finite element software ANSYS is used to analyze roadway displacement and stress under different support conditions, which including model with on support, with anchor support, with anchor and cable support and with U steel support. Some useful results, which have reference value to mine engineering, are achieved in this study.
Design Application of LQS20000 Column Strength Test Bench
Authors: Lui Peng Fei , Shao Xiao Wei , Meng Xiang Hui
Published: August 2013

Analyzed the trend of the development of hydraulic powered support and column, this paper designs a column strength test bench with 20000KN working resistance which combined with the new release of GB25974.2-2010 for coal mine hydraulic support and jack technical conditions of Part 2 standard requirements. Through the practical application, it turned out that the test bench has reasonable structure, stable performance and it can meet all of the following Ф630 bore hydraulic support column factory test requirements. The trend of the mine-used hydraulic support column and the performed new criterion demands manufacturers to enhance the ability of test equipment. In this situation, the 20000KN column strength test bench our company designed and manufactured not only do the loading test, but also apply external load at columns by simulating the actual working conditions, which is essential to Inspection and testing of dual-extension hydraulic columns middle cylinder strength.
An Ellipse Fitting Algorithm Applied to the Construction of the Elliptic Arc-Shaped Leading Edge
Authors: Yu Xiao Qiang , Ning Tao , Hou Yong Long , Chen Zhi Tong
Published: August 2013

In this paper, we proposed a new ellipse fitting method converting the ellipse fitting into a circle fitting based on projection transformation. Numerical experiments demonstrate that our approach have good stability and strong robustness against noise in addition to excellent precision and accuracy. In our further research, we successfully extend our algorithm to the construction of the elliptic arc-shaped leading edge by using a tangential contact constraint.
Keywords: Ellipse fitting; Projection; PSO; Leading edge
Study of Direct Quenching and Tempering Process of a Low Carbon Equivalent 960 MPa Grade Steel
Authors: Lu Feng , Wang Chao , Li Yuan Yuan , Lu Long , Wang Zhao Dong , Wang Guo Dong
Published: August 2013

The chemical composition of a 960 Mpa grade high strength steel with low carbon equivalent was designed. Effect of direct quenching and tempering process on the microstructure and mechanical properties of the experimental steel was studied. Results showed that fine lath martensite was obtained after controlled rolling and direct quenching. With tempering temperature increasing, the mechanical properties showed different trends for different tempering stages. And this had a direct relationship with the microstructure evolution. The matrix recovery softening, carbon desolution and precipitation of nanomicroalloy carbides influenced the strength change. With increase of tempering time, the strength decreased and toughness improved. Experimental steel tempered at 450 °C for 40min could obtain the best mechanical properties, which meet the requirement with a large impact energy margin.
The Influence of the Al-Ti-B/Al-Sr Modification on the Microstructure and Properties of the Hypereutectic Al-Si Alloy in Automotive Piston
Authors: Liu Meng Xiang , Chen Jian Mei
Published: August 2013

By using some types of means such as Optical Microscope (OM), Scanning Electron Microscopy(SEM), the testing of tensile mechanical properties and the testing of friction and wear, the impacts of the Al-5Ti-1B and Al-20Sr modification on the Al-16Si-4Cu-0.5Mg-0.2Mn alloy microstructure, mechanical properties and friction properties are researched. The results turn out that the modification can significantly refine the primary silicon and the eutectic silicon in the alloy, the Al-5Ti-1B mainly refined the primary silicon in the alloy, the Al-20Sr refined the eutectic silicon; the alloy’s effect of refinement after compound modification is better than that in separate metamorphism. Modification can improve the tensile strength and elongation of the alloy: the tensile strength of the alloy has been increased by 65MPa after its compound modification; also the elongation by 0.4%. Modification can improve wear-resisting property of the alloy and also its effect of compound modification is better than that of separate metamorphism. The modification mechanism of Al-5Ti-1B is that Al3Ti and TiB2 belongs to heterogeneous nucleation; while the modification mechanism of Al-20Sr is that the strontium changes the growth pattern of Si phase.
Influence of Thermo-Electropulsing Rolling Process on Microstructure and Mechanical Properties of AZ31 Magnesium Alloy Strip
Authors: Sun Shi Ding , Tang Guo Yi
Published: August 2013

Thermo-electropulsing rolling (TER) process, which combined the electropulsing treatment with the conventional warm rolling process (WR), was applied to manufacture AZ31 magnesium alloy strips in the current study. Influences of TER process and WR process on microstructure and mechanical properties of AZ31 Mg alloy were studied. TER process was found to induce and accelerate the dynamic recrystallization (DRX) behavior of the samples at a relatively low temperature within a short time. Besides, TER process could obtain samples with better mechanical properties than that of WR process.
Experimental Research on the Mechanical Behavior of the Cracked Aluminum Plate Bonded by the Graphite/Epoxy Composite Patch
Authors: Zhang Yi Shan , Wang Zun , Wang Zhi
Published: August 2013

The effect of the graphite/epoxy composite patch parameters on the static and fatigue strength of the cracked aluminum plate was investigated experimentally. A series of specimens repaired by six types of composite patches including four different patch lengths and two different patch thicknesses were tested on the material tester. Specimens single-sided repaired and double-sided repaired by the same composite patches were also tested. The experiment results show that composite patches can provide an improvement in static and fatigue strength of the cracked aluminum plate, double-sided repair is more effective than single-sided repair, if the thickness and the length were selected properly, the composite patches can significantly enhance the strength of the repaired specimens.
Experimental Research on the Stiffness of CFRP Reinforced Concrete Beam
Authors: Xu Xin , Liu Zheng , Han Xue , Ge Chao
Published: August 2013

This thesis analyses the destruction mode, the crack developing and beam deflection changes of 20 reinforced concrete beams including un-strengthened beam, direct strengthened beam and secondary load reinforced beam through tests and researches. The results show that using CFRP to strengthen the reinforced concrete beams will not only effectively increase the bearing capacity of the beam, but also inhibit the beam cracking and improve the flexural rigidity of the beam during normal use. In addition, the initial damage will have a certain impact on the stiffness of the strengthened beam.
Robot Soft Grabbing with New Piezoresistive Tactile Sensor
Authors: Chen Jin Jun , Xiang Ting
Published: August 2013

A type of tactile sensors based on piezoresistive principle is designed for the robot grab force detection and control. According to human behaves and awareness, the robot grabbing control program imitate human hand grasp active perception and action mechanisms. With the tactile sensors, the slip and grasping process pressure signal is sampled and analysed by general time-domain statistical parameter, and a simpler control algorithm is researched. In the experiment the robot has accomplished soft grabbing by modeling human hand action and applied appropriate grabbing force on objects of different weights or material by means of the control algorithm. Experiments suggest that this sensor and action biomimetic process is suitable to be used in the tele-presence technology application in the case of the visible range or visual equipment aid especially.
Research on the Customer Requirement Processing for Mass Customization
Authors: Zhang Yu Hua , He Yi Jing
Published: August 2013

This paper built the customer requirement processing flow for mass customization, and analyzes the customer group’s and discrete customer’s requirement processing flow. On this basis, the acquisition and criterion of customer requirement, the customer requirement information analysis, the evaluation of customer satisfaction(EOCS) has been studied and discussed.
The Influence of Gearbox Oil-Leak to the Bolt Joint in Wind Turbine Tower
Authors: Gao Yun Yan , Zhang Wen Zhi , Wang Hao
Published: August 2013

In the wind turbine system, high strength bolt is always used in important joint. For example, whether the bolt between wind turbine tower is safe is one important side of wind turbine protecting. However, the gearbox always loses oil even if wind turbine runs well, even the oil would leak on the bolt joint of each layer. So it is important to analysis the influence of oil-leak to bolt joint. Through analyzing the property of gear oil and the stress situation of bolt in wind turbine tower, the paper obtains the equilibrium formula of bolt joint in different stress situation and the influence of oil to frictionfactor and torque coefficient. At last, making a conclusion about the reson of causing bolt joint loosing when gearbox oil leaks on the bolt joint of wind turbine tower.
On Gradient Elasticity and Discrete Peridynamics with Applications to Beams and Plates
Authors: Reddy J.N. , Srinivasa A. , Arbind A. , Khodabakhshi P.
Published: August 2013

In this paper two different nonlinear elasticity theories that account for (a) geometric nonlinearityand (b) microstructure-dependent size effects are revisited to establish the connection betweenthe two theories. The first theory is based on modified couple stress theory of Yang et al. [1]and the second one is based on Srinivasa–Reddy gradient elasticity theory [2]. The modified couplestress theory includes a material length scale parameter that can capture the size effect in a material.The gradient elasticity theory was developed for finitely deforming hyperelastic cosserat continuum,and it is a generalization of small deformation couple stress theories. The Srinivasa–Reddy theorycontains, as a special case, the first one. These two theories are used to derive the governing equationsof beams and plates. In addition, a discrete peridynamics idea as an alternative to the conventionalperidynamics is also presented.
Smart Flow Control with Riblets
Authors: Choi Kwing So
Published: August 2013

A review of riblets as a smart flow control device is given. After the state-of-the-art examination of the drag reduction performance, different views on the drag reduction mechanism are put in perspective. Being a smart flow control device, riblets can control not only momentum, but also heat and flow noise. Some of the available results are summarized to encourage the readers to consider other applications of riblets. Although useful for research investigations, riblets films are not industrially friendly. Here, recent efforts in manufacturing the micro-groove surfacein situare reviewed, including an overview of patents relating to the production of riblets.
Optimisation of a Hybrid Energy Scavenger with Piezoelectric/Magnetic Coupling for Sensor-Bearing Units
Authors: Brusa Eugenio
Published: August 2013

Vibration monitoring based on wireless distributed sensors is currently used in steelmaking plants to early detect structural damage occurring in the rolling mill components. This approach allows overcoming some severe limitations of access to those industrial equipments, but sensors need a local power supply. Vibration energy harvesting based on piezoelectric materials is therefore proposed for this purpose. Nevertheless, very often it happens that dimensions of the energy scavenger are incompatible with the size of the system, thus not allowing a perfect tuning of its resonance upon the frequency of the dynamic excitation. Moreover, sometimes the amplitude of vibration is too low to induce a sufficient amount of energy conversion. Those problems motivated a previous work of the author, about the feasibility of plucking the flexible structure through either a relative motion or rotation of the harvested system and the energy scavenger, respectively. To avoid the drawbacks due to the wear in plucking the material, a contactless electromechanical coupling was proposed. The interaction between two permanent magnets, being one applied to the scavenger tip and the other fixed, was used to excite the vibration and the electromechanical conversion through the piezoelectric layer. The effectiveness of such hybrid system composed by the structure with surface bonded piezoelectric layers and the couple of magnets was investigated and compared to the power requirements of some sensors currently used to measure the dynamic response of the backup roll bearings located at the outer crown of the rolling mill. An optimisation of the whole device to increase the overall performance is proposed by following some approaches assessed in the literature and tested on some specimens of energy scavenger. The optimisation activity was based on a suitable selection of the piezoelectric material aimed at reaching the highest electromechanical coupling with a good mechanical strength and on a suitable shaping of the electrode surface aimed at assuring the largest efficiency in the energy conversion.
Dissolution Improvement of Itraconazole by a Nanoparticulate System Containing Lecithin-Pectin Complexes
Authors: Sriamornsak Pornsak , Limmatvapirat Sontaya , Cheewatanakornkool Kamonrak
Published: August 2013

Nanoparticulate system composing of polymeric or lipid materials have been proposed as drug carriers for improving efficacy of encapsulated drugs. Different materials, e.g. phospholipids and polysaccharides, have been proposed for the production of these systems due to their biocompatibility, biodegradability, low cost and safety. In this study, we report a novel particulate system containing lecithin-pectin complexes loaded with a lipophilic drug, itraconazole. The effect of pectin concentration on particle formation and drug dissolution was also investigated. The lecithin-pectin complexes were prepared by thin film method using soya lecithin and then hydrated with different concentration of pectin solution. The surface charge (zeta potential) and particle size of complex particles were characterized. The drug dissolution was determined by using USP dissolution apparatus. The results demonstrated that the particle size of complex particles were in nanometer range. When concentration of pectin increased, the size increased slightly while the surface charge of complex particles was less negative. The drug dissolution from complex particles containing lecithin and pectin was higher than those containing only pectin.
Evaluation of PEG-PPG-PEG Copolymer Blends for Using as Resorbable Bone Wax
Authors: Suvannapruk Waraporn , Thammarakcharoen Faungchat , Chokevivat Watchara , Rukskul Pattaravit , Suwanprateeb Jintamai
Published: August 2013

In this study, four types of PEG-PPG-PEG copolymers solids and pastes having different molecular mass (Mw~5800, 8400, 12000 and 14600) were selected and mixed at various compositions ranging from 40 to 60 % by weight. The textures and handling characteristics of the prepared samples were evaluated in comparison to that of the commercial non-resorbable bone wax. Thermal and mechanical properties of the blends were determined by a differential scanning calorimeter and a universal testing machine respectively. It was found that the combination of solid (Mw~8400) and paste-like (Mw~12000) copolymers at the ratio of 40:60 gave the closest smooth texture with good smearability and had similar melting temperature to the commercial bone wax, but having slightly lower compressive stiffness. Preliminary cytotoxicity of the selected formulations against osteoblasts revealed that the cell viability was greater than 70 % indicating that the prepared samples did not show any cytotoxic potential.
Preparation and Characterization of Plasma-Treated Porous Poly(glycerol sebacate) Scaffolds
Authors: Theerathanagorn Tharinee , Thavornyutikarn Boonlom , Janvikul Wanida
Published: August 2013

In this study, poly (glycerol sebacate) (PGS) was initially synthesized via condensation polymerization of glycerol and sebacic acid at equimolar ratio (1:1) at 130°C for 24 h. The number average molecular weight (Mn) of the resulting polymer determined by gel permeation chromatography (GPC) was about 2800 g/mol. Porous PGS scaffolds were subsequently prepared by a particle-leaching technique. NaCl was added into the polymer at 60-90% w/w; the mixtures were cured in Teflon molds at 140°C for 16 h. The porous scaffolds were further subjected to surface treatment with low pressure oxygen plasma to increase surface carboxyl and hydroxyl groups and thereby enhance hydrophilicity of PGS scaffold surface. The surface morphology and wettability of both untreated PGS and plasma-treated PGS scaffolds were comparatively determined by scanning electron microscopy (SEM) and water contact angle measurement, respectively. A considerable decrease in water contact angle was observed on the PGS scaffolds after the plasma treatment. The surface chemistry, mechanical strength and degree of swelling of the PGS scaffolds were also assessed by X-ray photoelectron spectroscopy (XPS), dynamic mechanical analysis (DMA) and swelling measurement, respectively.
Strengthening of Gravity Load Designed Reinforced Concrete Frames with the External RC Shear Walls
Authors: Bahadir Fatih , Kamanli Mehmet , Korkmaz Hasan Husnu , Balik Fatih Suleyman , Unal Alptug , Korkmaz Serra Zerrin
Published: August 2013

Turkey is situated on a very earthquake zone of the world namely Alp-Himalayan Earthquake Zone. Several destructive earthquakes resulted in high dead losses in the last century. Turkish building stock consisted of nonductile RC framed structures commonly 3 to 7 stories. The common properties of the existing structures is the poor lateral resistance. The residental buildings with poor earthquake resistance must be rehabilitated with a rapid, economical, feasible and effective strengthening methods. The external shear wall addition to the existing poor frame is studied experimentally in this study. 6 specimens were tested under reversed cyclic lateral loading simulating the seismic action. The first specimen was the reference specimen and didn't contain any strengthening and tested to see reference behaviour. The other specimens were strengthened with external shear walls with or without openings. The size of the openings is a parameter in the study. Secons specimen didn't contain any opening. Columns of the frames also jacketed with reinforced concrete. The maximum lateral load carrying capacity, ductility capacities, energy consuption capacities, improvement in the lateral rigidities were investigated.
Nafion-Silane Modified Mordenite Composite Membrane Synthesis and Characterization for Direct Ethanol Fuel Cell
Authors: Kanjanapaisit Sawanya , Prapainainar Chaiwat , Prapainainar Paweena
Published: August 2013

Composite membranes, consist of Nafion and surface-modified mordenite as inorganic filler functioned as ethanol barrier, were prepared and used for direct ethanol fuel cell (DEFC). mordenite was modified using gamma-glycidoxypropyltrimethoxysilane (GMPTS) which has the epoxide group and 3-mercaptopropyl-trimethoxysilane (MPTS) which has the mercapto group as coupling agents on mordenite. The composite membranes were fabricated by adding 5 %weight modified mordenite into Nafion by solution casting and hot pressing with catalyst to produce MEA and tested in DEFC single cell stack. XRD, FT-IR, Mastersizer and SEM were used to study the morphology, physical and chemical properties of the filler and the composite membrane. The characterizations also included ethanol permeability and proton conductivity by using the diffusion cell and AC impedance test, respectively. The performance of the cell was evaluated in the DEFC under cell temperature from 30 to 70 °C and ethanol concentration of 1 M to 4 M. It was then compared to the recasted Nafion membrane.
Effect of Photocatalytic Coating on Concentrator Photovoltaic Module
Authors: Sueto Tsuyoshi , Nishioka Kensuke
Published: August 2013

The anti-soiling layer was coated on the surface of Fresnel lens for concentrator photovoltaic. The anti-soiling layer was prepared by coating the acrylic urethane capping layer, the inorganic/organic nanograded intermediate layer, and the photocatalytic surface layer including modified WO3 and partial hydrolyzed tetraethyl orthosilicate. The adherent sand for the sample without coating was 0.023 g and that for the sample with coating was 0.008 g. The adhesion of sand was suppressed owing to the effect of the anti-soiling coating. The electrostatic potential for the sample without coating was 0.23 kV, and the value was much higher than that for the sample with coating. The electrostatic charge at the surface of sample was suppressed with the anti-soiling coating.
Biocomposites from Cassava Pulp/Polylactic Acid/Poly(butylene Succinate)
Authors: Kangwanwatthanasiri Parina , Suppakarn Nitinat , Ruksakulpiwat Chaiwat , Yupaporn Ruksakulpiwat
Published: August 2013

In this study, effect of PBS content on physical properties of polylactic acid (PLA) and polybutylene succinate (PBS) blends was studied. The content of PBS was varied from 0 30 %wt. The blends were mixed using an internal mixer. The samples were prepared using a compression molding. It was shown that tensile strength and Youngs modulus of PLA/PBS blends were decreased with increasing PBS content from to 0 30 %wt. Nevertheless, elongation at break and impact strength of the blend were increased with increasing the amount of PBS up to 20 %wt. Polylactic acid grafted glycidyl methacrylate (PLA-g-GMA) was used as the compatibilizer in PLA/PBS/PLA-g-GMA blends. PLA-g-GMA was shown to improve interfacial adhesion between PLA and PBS. With the addition of PLA-g-GMA, mechanical properties of PLA/PBS blend were improved. The preparation of cassava pulp (CP) to be used as filler in PLA/PBS blends and PLA/PBS/PLA-g-GMA blends was studied. Effect of CP content on mechanical properties CP/PLA/PBS composites was studied. PLA-g-GMA was also used as compatibilizer in CP/PLA/PBS composites. The mechanical properties of CP/PLA/PBS composites were improved with the addition of PLA-g-GMA as well.
Density Reduction and Electrical Conductivity Induction in Wood Plastic Composites
Authors: Ern Asaph Ooi Wei , Ming Tan Chun , Jayaraman Krishnan
Published: August 2013

ncreasing environmental awareness has led to an increase in the usage of wood plastic composites in many countries. The primary objective of this research was the decrease in the density of wood particle-polypropylene composites using chemical blowing agents while retaining their mechanical properties. Different amounts of Azodicarbonamide (0%, 1% and 2% by weight) were mixed with four blends consisting of wood particles (15%, 25%, 35% and 45% by weight), Epolene (2% by weight) and polypropylene and compounded in an extruder. The resulting extrudates were granulated, injection-moulded into specimens and tested for density, tensile strength and impact strength. The secondary objective of this research was the increase in the electrical conductivity of wood particle-polypropylene composites using conducting agents for novel end usages. Different amounts of carbon black (1%, 3%, 5%, 7% and 10% by weight) were mixed with a blend consisting of wood particles (45% by weight), epolene (2% by weight) and polypropylene and compounded in an extruder. The resulting extrudates were granulated, compression-moulded into plates, machined into specimens and tested for electrical conductivity and tensile strength.
An Experimental Study on Reinforced Concrete Infilled Frames with Openings
Authors: Balik Fatih Suleyman , Korkmaz Hasan Husnu , Kamanli Mehmet , Bahadir Fatih , Korkmaz Serra Zerrin , Unal Alptug
Published: August 2013

In the last decade, seven major earthquakes caused significant casualties and extensive structural failures. Thousands of RC buildings were severely damaged or collapsed in Turkey due to various deficiencies. This has initiated experimental studies on strengthening methods and intensive researches regarding the rehabilitation of reinforced concrete structures by introducing reinforced concrete infill walls were carried out. Strengthening of reinforced concrete frames by cast-in-place reinforced concrete infills is commonly used in practice. Many structures were also repaired using this technique after the recent earthquakes. In this experimental research, six, one-bay/two-story, 1/3-scaled non-ductile, undamaged reinforced concrete (RC) frames were constructed and tested to investigate the behavior of frames strengthened by introducing infills with or without openings. The test specimens were subjected to reversed cyclic quasi-static lateral loading. The specimens were constructed with the most commonly observed deficiencies in residential RC buildings in Turkey. The first specimen was the reference bare specimen and contained no strengthening. The other specimens were infilled with RC panels with openings having different ratios and configurations. Strength, stiffness and storey drifts of the test specimens were measured and compared. Test results indicated that infilled RC frames displayed significantly higher lateral strength and stiffness than the non-ductile bare frame considerably.
The Structural Damages and Collapse Types in Turkey, Observed after the Recent Earthquake
Authors: Korkmaz Serra Zerrin , Korkmaz Hasan Husnu
Published: August 2013

In the last decade, the earthquakes in Turkey caused thousands of loss of life. The most unfortunate case was happened in 1999 Marmara earthquake and more than 20000 people lost their life. Recently an earthquake of magnitude 7.2 occurred in Van city and 600 dead toll was reported. Following the earthquake, the author was visited the earthquake region. In this study field reconnaissance survey the causes of failures observed on reinforced concrete (RC) structures were summarized. The main problem was the construction quality especially the concrete production process. The steel detailing was also a big problem for the region. The failed or damaged buildings were included several non-seismic details. The observed problems of damaged or collapsed buildings were short column formations, soft or weak stories, inadequate lateral confinements reinforcement, use of plain undeformed bars, poor material and concrete quality, lap spilice problems, strong beam-weak columns and weak beam-column joints.
New Polyimide Based Composite Films for Fuel Cells: Study of the Porous Structure
Authors: Ratieuville Vincent , Fatyeyeva Kateryna , Chappey Corinne , Rogalskyy Sergiy , Tarasyuk Oksana , Marais Stéphane
Published: August 2013

New porous polyimide films were elaborated by vapor induced phase separation process. The influence of different parameters such as the nature of the solvent, the molecular weight of the porous agent, and relative humidity on the structure of the film was investigated. It was shown that the porous film prepared from NMP presents the most original morphology with micro-and nanopores. Moreover, such structure is only obtained when the porous agent used has a high molecular weight. The synthesized porous film was swelled in protic ionic liquid for fuel cell application. The performed conductivity measurements as a function of temperature have shown that the conductivity of the impregnated polyimide film increases when the temperature rises up to 150 °C following Arrhenius behavior.
Silica-Reinforced Natural Rubber with Epoxidized Low Molecular Weight Rubber as a Compatibilizer
Authors: Saramolee Prachid , Sahakaro Kannika , Lopattananon Natinee , Dierkes Wilma , Noordermeer Jacques W.M.
Published: August 2013

This work investigates the effect of epoxidized low molecular weight natural rubber (ELMWNR) in silica-filled NR compounds on processing, mechanical and dynamic mechanical properties. The ELMWNRs with mol% epoxide groups varying from 0-50 and molecular weight in a range of 50,000-60,000 g/mol were prepared from depolymerization of epoxidized natural rubber using periodic acid in latex state. They were then added in the silica-filled NR compounds as a compatibilizer at varying loading from 0-15 phr. The addition of ELMWNR decreases compound viscosity and Payne effect, i.e. filler-filler interaction. The optimal mechanical properties of silica-filled vulcanizates are observed at the ELMWNR-28 (28 mol% epoxide) loading of 10 phr. The incorporation of ELMWNR with 28 and 51 mol% epoxide groups into NR compounds introduces a second glass transition temperature and affects on their dynamic mechanical properties. Higher epoxide content leads to higher Tan δ of the rubber vulcanizates in the range of normal service temperature.
Dispersion Enhancement of Multi-Walled Carbon Nanotube (MWCNT) in Nitrile Rubber (NBR)
Authors: Boonbumrung Atip , Sea-Oui Pongdhorn , Sirisinha Chakrit
Published: August 2013

Attempts to enhance dispersion degree of multi-walled carbon nanotubes (CNT) in nitrile rubber (NBR) matrix, and to improve the NBR-CNT interaction were carried out by different approaches, namely, sonication and chemical treatments of CNTs with nitric acid (HNO3), nitric-sulfuric acid mixture (HNO3/H2SO4) and potassium permanganate (KMnO4). Rheological behavior of NBR/CNT composites was monitored as an indication of filler dispersion degree using the Rubber Process Analyzer (RPA2000) via the alteration in Payne effect. Results gained reveal the magnitude of Payne effect in the following order: untreated system> sonicated system> HNO3 system> HNO3/H2SO4 KMnO4 system, implying a significant improvement in the state-of-mix of NBR/CNT composites by sonication and/or chemical treatment of CNT prior to being mixed with NBR. The SEM results demonstrate the highest magnitude of CNT dispersion in the system with HNO3 followed by the sonicated system untreated system, HNO3/H2SO4 KMnO4. The SEM results suggest that the surface treatment of CNT with HNO3 yields highest magnitude of improvement in CNT dispersion. Poor CNT dispersion after treatment with HNO3/H2SO4 or KMnO4 is due probably to the re-agglomeration of CNT during the drying stage after the chemical treatment process.
Effects of Mold Temperature and Casting Temperature on Hot Cracking in Al-4.5 wt.% Cu Alloy
Authors: Burapa R. , Rawangwong S. , Chatthong J. , Boonchouytan Worapong
Published: August 2013

Hot cracking is an important defect that occurs during solidification of aluminum-copper alloys. In this present work, the effects of mold temperature and casting temperature on hot cracking in the Al-4.5 wt.% Cu alloy has been studied using a ring mold for hot cracking assessment. For the experimental conditions, three mold temperatures between 150 and 350°C and three casting temperatures between 670 and 770°C were studied and Al-7 wt.% Si alloy was used as reference for comparison. The results showed Al-7 wt.% Si alloy has high resistance to hot cracking and no hot cracking forms under three different mold temperatures, while Al-4.5 wt.% Cu alloy shows significant hot cracking tendency under the same casting conditions. The severity of hot cracking in Al-4.5 wt.% Cu alloy decreased significantly with increasing the mold temperature and decreasing the casting temperature. On the other hand, an increasing casting temperature resulted in severer hot cracking in Al-4.5 wt.% Cu alloy.
Flow Properties and Melt Distortion in Molten Rubber Compounds under Capillary Extrusion
Authors: Chookaew Watcharapong , Sukniyom Yanichsa , Patcharaphun Somjate , Sombatsompop Narongrit
Published: August 2013

The influences of shear rate and vulcanizing system on the rheological properties and melt fracture of natural rubber compounds were investigated by using a rate-controlled capillary rheometer. The rheological properties of rubber compounds were characterized with respect to the apparent viscosity and extrudate swell. The measured results indicated that the apparent viscosity tended to decrease with increasing shear rate. This was due to the pseudoplastic behavior of molten rubber compound. It was evident that rubber compound using EV system showed the lowest apparent viscosity as compared to those obtained by CV and NS systems, respectively. This was due to the occurrences of premature crosslink at the skin layer and the wall slip of rubber compound during the flow in capillary die. Furthermore, the onset of smooth surface was also observed which depending on the types of crosslink at the skin layer.
Bimetallic LaNi1-xCoxO3 (x=0, 0.3, 0.5, 0.7, and 1) Perovskite Catalysts for Tar Reforming to Syngas
Authors: Soongprasit Chakrit , Aht-Ong Duangdao , Atong Duangduen
Published: August 2013

Perovskite-type oxide with transition metal as active site presented a promising potential catalyst for tar elimination in gasification process. LaNi1-xCoxO3 (x= 0, 0.3, 0.5, 0.7, and 1) were prepared by sol-gel method. The XRD profiles of the calcined catalysts revealed the mixed metal oxide forms including LaNiO3 and LaCoO3 rhombohedral structures. Good dispersion of La, Ni, and Co with homogenous structure was observed in synthesized catalyst. The particle size and surface area were in the range of 12.64-21.86 μm and 3.89-11.69 m2 /g, respectively. Activity of prepared catalysts on tar elimination was carried out using steam reforming of toluene as tar model compound at 500, 600, 700, and 800°C. Product distributions obtained from reforming reaction with LaNi1-xCoxO3 were between 40.24-88.84% of gas, 10.99-59.59% of liquid, and 0.15-0.17% of solid. Conversion to CO and H2 were found to increase with the reaction temperature. The maximum carbon and hydrogen conversion to syngas, CO and H2, of approximately 78.42% and 83.49% with acceptable heating value were occurred at 800oC using LaNiO3 as catalyst. Crystal structure of used catalysts clearly showed destruction of perovskite structure and transformation to metallic Ni and Co at effective temperature.
Effects of Frequency and Sonication Time on Ultrasonic Degradation of Natural Rubber Latex
Authors: Utara S. , Moonart U.
Published: August 2013

Ultrasonic degradation of fresh latex was investigated at frequencies of 20 and 25 kHz, at a constant temperature of 25o C (±1o C) to avoid temperature-related effects. The time-dependent evolution of the molecular weight of the natural rubber latex was determined using gel permeation chromatography, and its structure by means of the fourier transform infrared (FTIR) technique. A 10 minute period of sonication resulted in reduction in the molecular weight of both the 20 and 25 kHz treated samples, the lowest average molecular weight () being obtained in the case of the 25 kHz sample. The of the 25 kHz sample also decreased with increasing latex concentration. However, after 30 minutes, fluctuations had occurred in both samples with respect to the and and also the molecular weight distributions, an effect possibly explained by the competing processes of chain scission and radically-induced cross-linking of the polymer chains. The FTIR results also suggest that the structure of polyisoprene is unaltered by ultrasonic wave treatment at these frequencies.
Preparation and Characterization of Guanidinylated Chitosan/β-Glycerophosphate Thermo-Sensitive Hydrogel
Authors: Qi Xue Jie , Cui Yuan Lu , Wang Qiang Song , Qi Yun
Published: August 2013

The purpose of this study was to prepare and characterize guanidinylated chitosan/β-glycerophosphate thermo-sensitive hydrogel system. The primary amine group of chitosan was modified with guanidine group, which was characterized by FT-IR and1H NMR. The results showed that the guanidinylations had been successfully carried out in cyanamide and chitosan. Gelation temperature was modulated at 37 °C with the ratio of 50% β-GP solution (weight/volume) and 4% GCS solution (weight/volume) at pH value ranged from 6.9 to 7.2, which could be development a new drug delivery system at body temperature.
Development on the Synthesis of Phosphodieseterase Type 5 (PDE5) Inhibitors
Authors: Ma Yu Zhen , Zhang Guang Zhou
Published: August 2013

Phosphodieseterase type 5 inhibitors are safe, efficacy and well tolerated in the treatment of erectile dysfunction and therefore widely used. In this paper, the various synthetic methods and development on the synthesis of sildenafil,vardenafil,tadalafil are evaluated.
Chloroplast TrnL-F Sequences Analysis of Pulsatilla koreana Nakai. and Potentilla chinesis Ser.
Authors: Zhang Shao Xuan , Liu Feng , Wang Bo Chuan , Ling Yun Hui , Sun De Jun , Lin Guang Zhu
Published: August 2013

To provide scientific data of the chloroplast TrnL-F sequences for the authentication of Pulsatilla chinesis (Bge) Regel, we extracted the genome DNA from the leaves of Pulsatilla koreana Nakai. and Potetilla chinesis Ser. collected in Jilin Province, amplified the chloroplast TrnL-F region using universal primers and sequenced the purified PCR products directly. The obtained sequences were edited by Genetyx and reported here.
ITS Sequences Analysis of Pulsatilla koreana Nakai. and Potentilla chinesis Ser.
Authors: Zhang Shao Xuan , Liu Feng , Ling Yun Hui , Wang Bo Chuan , Sun De Jun , Lin Guang Zhu
Published: August 2013

To provide scientific data of the internal transcribed spacer (ITS) sequences for the authentication of Pulsatilla chinesis (Bge) Regel, we extracted the genome DNA from the leaves of Pulsatilla koreana Nakai. and Potetilla chinesis Ser. collected in Jilin Province, amplified the ITS region using ITS universal primers of angiosperm, and sequenced the purified PCR products directly. Polymorphism of ITS sequences was found within P. chinensis Ser. and the sequence data suggested that our samples of this species might be related to hybridization. The obtained sequences were edited by Genetyx and reported here.
Scanning Electron Microscopic Study of Rotary Nickel-Titanium Endodontic File (RNEF)
Authors: Wu Chun Tung , Chung C.Y.
Published: August 2013

This study examined RNEF with scanning electron microscope (SEM), for surface flaws, internal voids and inclusions. Six commercial brands of 4% taper RNEF: PF (#25, 25mm, Dentsply Tulsa Dental Specialties, Tulsa, OK), GTX (#20, 25mm, Dentsply Tulsa Dental Specialties, Tulsa, OK), NRT (#25, 25mm, MANI Inc., Tochigi, Japan), FKG (#25, 25mm, FKG, Dentaire), K3 (#25, 25mm) and TF (Twisted File #25, 27mm) (Sybron Kerr, Orange, CA) were examined. Full length and 4mm segment of each RNEF brand was mounted in Al plate for surface morphology and conductive epoxy resin for cross-sectional imaging with SEM (JEOL JSM-820) respectively. EDX spectrum was collected from specimens with EDX spectrometer coupled to SEM. EDX software was used for quantitative analysis. This study demonstrated the existence of surface flaws as machining marks, notches, crevices, fissures and pits. Internal voids of micro-to sub-micrometer magnitude were observed. Ti-rich inclusions were found dispersed in the equiatomic to near-equiatomic NiTi substrate of RNEF. Surface flaws, internal voids and inclusions were common findings on RNEF studied. Their effects on the corrosion and fatigue resistance of RNEF deserve further investigation.
Research on the Performances of Automotive Seating Fabrics
Authors: Cui Yun Hua , Jin Liang Ying
Published: August 2013

This paper was written based on the testing of resistance to stretch & set and bond strength for 10 different kinds of automotive seating fabrics and their corresponding surface monolayer fabrics, according to the standard GMW3211FZT01034-2008/FZT70006-2004GMW3220. And the results indicated that, resistance to stretch & set of knitted automotive seating fabrics decreased and that of woven fabrics increased after composited; bond strength of fabric/sponge was higher than that of sponge/bottom, and bond strength of seating fabrics which had different structures were also different. Studying the performance of automotive seating fabrics had important implications on the production of seating fabrics, and the improvement of product quality and innovation in future.