bluuebunny/crossref_metadata_2025 huggingface dataset:
Technical and Economic Analysis for Harmonic Distortion Impact and Mitigation Technique in Power Networks
Authors: Rugthaichareoncheep Nattachote , Chaladying Saran
Published: June 2017

This research proposes technical and economic analysis of harmonic distortion impact and mitigation technique in power networks. Main proposal of research is analysis of harmonic impact and harmonic solution by regarding to economic decency for investment. Parallel resonance is harmonic impact that will be mentioned in this research because it is a problem that is mostly emerged in industries that contain non-linear loads and power factor correction devices. Its impact on power network is high voltage and current amplification, which link to equipment and system failure. An application of detuned filter will be proposed to solve the problem due to its popularity (It is a basic solution, easier and more inexpensive than the other solution). Parallel resonance condition will be modeled with an industrial power network, which contains a power transformer, a non-linear load (AC drive), a power factor correction device (capacitor bank) and a harmonic correction device (detuned filter bank), by using electrical, mathematical and payback period formulas. The results will illustrated the impact of parallel resonance phenomenon due to harmonic distortion in power network.
The Study and Screening of Bacteria for Silver Nanoparticle Biosynthesis
Authors: Kanthang Paisan
Published: June 2017

The silver refinery is very important for west management in the jewelry industry. In this work, we proposed the alternative of silver refinery process by using microorganism pathway. We focused on the isolation of microorganism which was found from manufacturing process and forming in gems and jewelry industry. Results showed that the initial silver refinery microorganism performed only in terms of Pseudomonas genus especially in AgNO3 solution. In contrast, Bacillus genus was not clearly effective silver refinery. These results could be the basis information to establish and develop system for silver refinery and/or silver quality improvement with biological process in future.
Production of Essention Oil from Tobacco Leaves for Insect Repellents
Authors: Boonyaroj Varinthorn , Amornkaew Amara
Published: June 2017

The production of essential oil from tobacco leaves for insect repellents using a combination of solvent extraction was investigated. Tobacco essential oil is generally different from other essential oils, which usually consist of several special aroma compounds. The tobacco essential oil and solvent extracts were analyzed by gas chromatography with a mass spectrometer (GC–MS). Tobacco essential oils are concentrated odorous substances. Nicotine is present as a major substance and found only trace amounts of the essential oils. Nicotine is an insecticide that affects to insects. This research showed that a development of products forms tobacco leaves and environmentally. This product evaporated pass through a packaging made from luffa gourd. The luffa gourd is a natural packaging can be easily degradation in the environment. Moreover, this product also helped to reduce the hazardous chemicals or pesticides usage in agricultural activities and not residues in the environment for long times.
Enhancing of Acetic Acid Production in Vinegar Production by the Consortium of Aspergillus spp. and Yeasts
Authors: Nicomrat Duongruitai
Published: June 2017

Fresh fruit vinegar fermentation is well known for the activities of diverse groups of microorganisms at two stages of the fermentation process. Their species diversity depend on the raw materials fermented. In the study, at the first step of high sugar production, less culturable acetic acid bacterial species but more Aspergillus spp. and yeasts, non-Saccharomyces were detected. At the end, the vinegar production step, the fermented broth showed only dominant acetic acid bacteria. In the study, yeasts and fungi were isolated and inoculated to the juice. The results showed that these consortium could help increase high alcohol and later more acetic acid production when compared with the control fruit vinegar fermentation.
Assorted Lactic Acid Bacteria with Yeasts in Alcohol Submerged Fermentation Step of Vinegar Production
Authors: Nicomrat Duongruitai , Chamutpong Siriphatrc
Published: June 2017

In the spontaneous vinegar fermentation process, diverse microorganisms considered as crucial microorganisms to succession of the vinegar fermentation control most pathogenic microorganisms. The predominant communities in fermented vinegar are acetic acid bacteria (AAB) functioning at the last step of acetic acid formation. However, lactic acid bacteria (LAB) also present in the vinegar, help produce high, quality vinegar and involve in the initial phase of starch degradation and alcohol production. In this study, the research was performed to understand the effects of LAB together with yeasts, Saccharomyces cerevisiae on on alcoholic and acetification production. In the experiment, mixtures of isolated LAB from fermented banana vinegar were tested for their functions together with yeasts in the alcoholic fermentation step. The results showed that indigenous LAB had more predominant effective species helping the induction of sugar but reduction in pH. This observation thus indicated the importance of inoculated LAB isolates in vinegar fermentation process as enhancer of the quality in vinegar fermentation.
Synthesis Hydroxyapatite from Three Types Eggsshells by Co-Precipitation Method
Authors: Taewana Thitiyada , Wongmaneerung Rewadee
Published: June 2017

In the present work, hydroxyapatite (HAp) were synthesised from three types eggshells (hen eggshells, duck eggsshells and quail eggsshells) by co-precipitation method. By using recycled eggshells, there were calcined at 700-900 °C for 2 h to form calcium carbonate (CaCO3). Then, CaCO3 and ammonium dihydrogenphosphate (NH4H2PO4) were used as precursor to produce HAp. The molar ratio of Ca to P was 1.67 : 1. In order to determine the most suitable calcination temperature to produce HAp based on purity of CaCO3, HAp were investigated over the temperatures range of 800-1100 °C for 2 h. Phase formation and microstructure evolution of HAp samples were determined by using (XRD), (SEM) and (FTIR) respectively. The results showed that CaCO3 formed at 700 °C for 2 h of all eggshell types. XRD investigations show that HAp powder were stable up to 1100 °C with hexagonal structure. SEMinvestigations demonstrate that the HAp powder obtained with a sphere morphology and FTIR confirmed that the HAp powder calcined at 1100 °C corresponded to the phosphate group in PO43- with significant characteristic peaks at 1026.5 and 563.9 cm-1.
Effect of Fish Scales Gelatin and Mixing Ratio on Chemical and Mechanical Characteristics of Gelatin/Chitosan Films
Authors: Nuamsrinuan Nisakorn , Suttisiri Noppadon , Hoonnivathana Ekachai , Limsuwan Pichet , Naemchanthara Kittisakchai
Published: June 2017

The objective of this work was to compare the chemical properties and mechanical properties (strength and elongation) of gelatin/chitosan (G/Ch) films. The effect of several fish scales such as white perch, java barb, red tilapia and nile tilapia scales and mixing ratios of G/Ch composite was investigated. Several fish scales were cleaned and treated with 1.0 M NaOH and 0.8 M acetic acid at room temperature for 120 min to remove fat. Gelatins were extracted from fish scales using the distilled water at 70°C for 120 min. Chitosan solution was prepared with 1% (w/v) chitosan in 1% (v/v) acetic acid, stirred at room temperature. After that, the G/Ch films were prepared by mixing the fish scale gelatins and chitosan with different ratios and then dried at 70°C. The results showed that the FT-IR of G/Ch films revealed the function groups of both gelatin and chitosan. The gelatin films showed peaks amide A (3219-3315 cm-1), alkane (2930-2958 cm1, 1400 -1479 cm-1and 675-1000 cm-1), amide I (1630-1655 cm-1), amide II (1520-1560 cm-1), amide III (1220-1335 cm-1), and ether (1020-1035 cm-1). The chitosan films showed peaks amide II (1559 cm-1), alkane (1404 cm-1) and ether (1022 cm-1). The tensile strength results of G/Ch films increased and elongation of G/Ch films decreased with increasing the amount of chitosan.
Inactivation of Bread Molds on Agar by Atmospheric Pressure Plasma Jet
Authors: Thonglor Panakamon , Amnuaycheewa Plaimein
Published: June 2017

The aim of this study was to evaluate the effect of argon plasma jet, generated at atmospheric pressure, on Aspergillus sp. The molds were isolated from commercial white bread and inoculated on potato dextrose agar (PDA) containing 10% tartaric acid. The atmospheric pressure plasma jet (APPJ) was generated at a high frequency (43 kHz) power of 10, 20, or 30W and applied to the inoculated molds on PDA for 5, 10, or 20 minutes. The PDA plates were incubated for 3 and 6 days and the fungal inactivation was investigated directly under light microscope and indirectly by comparing the fungal dry weights. The results indicated that higher power supply and longer plasma exposure time led to more reduction in the fungal dry weight. The APPJ appears to be effective in destroying Aspergillus sp., yet the optimal plasma treatment condition remains to be optimized.
The Selection of Appropriate Process Parameters of Diffusion Bonding in Heterogeneous Weld of 355J2/AISI 316L Steels
Authors: Moravec Jaromír , Nováková Iva
Published: June 2017

The aim of this article is to present possibilities of diffusion bonding utilization at creation heterogeneous joints where strength properties are taken into account. The joint was implemented to low-alloy structural ferrite-pearlite S355J2 steel and high-alloy austenitic AISI 316L steel. The fundamental theory of diffusion and also design and realisation of experimental creation of diffusion joint in thermal-mechanical simulator Gleeble 3500 is described in the article. Furthermore, procedure of technological parameters selection, when optimisation of strength properties of heterogeneous joint including metallographic evaluation are taken into account, are presented.
Research on Formability of Multi-Point Press Forming for 08Al and 2024-O Sheet
Authors: Chen Jun , Fu Wen Zhi , Li Ming Zhe , Wang Yu , Deng Yu Shan
Published: June 2017

Unlike multi-point die forming (MPDF), multi-point press forming (MPPF) takes full advantage of the flexibility of multi-point forming (MPF). In the process of MPPF, the punch elements always keep in contact with the sheet metal, developing instantaneous forming surfaces, which clamp and deform the plates. In this study, based on the spherical surfaces, the formability of both MPPF and MPDF were simulated through finite element software. The effects of the two methods on dimple, wrinkle and springback defect were comparatively analyzed. Also the shape error of MPPF was studied. We find MPPF can significantly inhibit dimple and wrinkle, thus obviously reducing the maximum strain and homogenizing the distributions of stress and strain of the parts. The largest vertical springback value decreases from 0.514mm to 0.257mm and the stress is released more completely after unloading. The edge effect reduces the curvature in the area far away from the center, greatly magnifying the shape error. The increase in the numbers of punch elements and in the dimensions of elastic cushions can significantly weaken the edge effect and improve the forming precision. These analyses show MPPF has better formability for metal sheets than MPDF.
Effects on Surface Integrity of Ti6Al4V in High Speed Milling
Authors: Fang Yong Feng , Tee Kong Fah
Published: June 2017

Surface topography is a significant factor that affects directly the surface integrity. There are several influencing factors. The purpose of the study is to investigate the effects of edge radius on surface integrity of Ti6Al4V. The proposed approach uses three different angles to study the relationship between the edge radius and surface roughness. The study develops theoretical model, roughness model based on cutting force and roughness empirical model. Experimental results show that machined surface integrity of TC4 is sensitive to the variations of the edge radius. The method is effective and can provide a guidance to optimize edge radius. It has realized higher accurate prediction of surface integrality in precision high speed milling with one of the models and has improved surface roughness quality of the work-piece.
Effect of Carbon Addition on the Cast and Rolled Microstructures of FeCoCrNiMn High Entropy Alloys
Authors: Ko Jun Yeong , Hong Sun Ig
Published: June 2017

In this study, the effect of carbon addition the cast and rolled microstructures of Cantor alloy type FeCoCrNiMn high entropy alloys. Both as-cast FeCoCrNiMn and FeCoCrNiMnC0.1 alloys have dendritic microstructure. Small particles, which may be associated carbon addition exist in the dendrite arms in FeCoCrNiMnC0.1 alloy. After homogenization treatment at 1327K for 24 hrs., dendritic structure was completely eliminated after annealing. Dendritic structure was converted to the structure with elongated grains, especially for carbon added FeCoCrNiMnC0.1. The development of elongated grains is associated with the direction of the primary arms in the dendritic structure. Carbides are segregated at the grain boundaries in FeCoCrNiMnC0.1 alloy. It also appears that growth of grains is impeded by the segregation of carbides. It is apparent that the grain boundary precipitates are Cr-rich. Both the strength and ductility of FeCoCrNiMnC0.1 increased over FeCoCrNiMn with the addition of 0.1 wt. % carbon. The increase of ductility in FeCoCrNiMnC0.1 may be caused by the rapid hardening in FeCoCrNiMnC0.1 due to dislocation-solute interaction.
Morphology and Wettability of Nanoporous Aluminium Oxide Film Prepared by Anodization
Authors: Watcharenwong Apichon , Saijaioup Narudon , Bailuang Yotsapon , Kajitvitchyanukul Puangrat
Published: June 2017

Anodic aluminium oxide (AAO) is a well-known material for nanofabrication. To obtain highly ordered nanoporous array, there is anodization process. AAO were fabricated by anodization method utilizing high purity aluminium foil as the substrate. The substrate was degreased with ultrasonic cleaner for 15 minutes. Then the substrate was anodized in an electrolyte of 0.3 M oxalic acid with various potentials: 10, 20, 30, and 40 V and various durations: 10, 30, 60, 120, and 180 minutes at room temperature. Field emission scanning electron microscope (FE-SEM) was used to investigate surface morphology of nanoporous aluminium oxide film. The wettability of nanoporous aluminium oxide surface was estimated by measuring water contact angle (WCA) of water droplets on the nanoporous aluminium oxide surface. The FE-SEM images showed that the pore size was in the range of 12 - 81 nm. This result can indicated that nanopore size of AAO film increased with the increasing of anodization potentials and anodization time. The water contact angle of AAO samples were approximately 90.55 - 44.33 degrees. The result of measurement proved that super hydrophilic surface obtained with the increasing of nanopore size and high porosity of AAO.
Real-Time Monitoring of the Dispersion Stability of Poly(Carbonate Urethane)s Using the Turbiscan Technique
Authors: Kim Tae Hee , Kim Jin Chul , Seo Bong Kuk
Published: June 2017

Waterborne poly(carbonate urethane) dispersions (WPCUDs) have received much attention from both academia and the chemical industry due to their potential applications in high-performance volatile organic compound-free coatings and adhesives. Commercially, both the long-term stability and the mechanical properties of WPCUDs are extremely important because these are closely related to the storage life of the product. This study provides a detailed, real-time investigation into the dispersion stability of WPCUDs. Various WPCUDs with different ionic contents and containing polyols of different molecular weights were prepared, and their dispersion stabilities were monitored in real-time using Turbiscan measurements. The effect of temperature and concentration on dispersion stability was also examined. The thermal and mechanical properties of WPCUD were characterized by thermogravimetric analysis, differential scanning calorimetry, and universal testing machine, and the data were correlated to the dispersion stability data.
Antibacterial and Mechanical Properties of the TiO2/ABS Composites
Authors: Sangkatip Rittichai , Sriseubsai Wipoo , Kiatkittipong Kunlanan
Published: June 2017

The aim of this present work is to enhance photoantibacterial performance on a surface of Acrylonitrile-Butadiene-Styrene (ABS) by mixing titanium dioxide (TiO2). The influences of different ratios for TiO2 under UV light irradiation were investigated according to JIS Z 2801: 2010 standard. 0.5%, 1% and 2% TiO2/ABS were formed by melting process with internal mixer and compression molding process. E.coli were chosen as a model of bacteria. The best photoantibacterial activity was provided by 0.5% TiO2/ABS. The result showed that E.coli could reduce up to 46.95%. However, a higher amount of TiO2 (i.e., 1% and 2% TiO2/ABS) obstructed the reaction, and E.coli was reduced to 42.6% and 36.08%, respectively. This was due to its aggregation observed from SEM image. For mechanical properties for TiO2/ABS, The results showed that tensile modulus and tensile strength of blending TiO2 at 0.5 %wt was the highest but the tensile was decreased when increasing TiO2 in polymer blended.
Creep Behaviors of CrMnFeCoNi High Entropy Alloy at Intermediate Temperatures
Authors: Kang You Bin , Lee Kap Ho , Hong Sun Ig
Published: June 2017

In this study, creep properties and fracture behavior of CrMnFeCoNi high entropy alloy (HEA) were studied at intermediate temperatures. The invert-type transient primary creep behaviors were observed in CrMnFeCoNi high entropy alloy. Creep behaviors of HEA are similar to those of class I solid solution alloys. The transient creep curves upon increase of stress by 5MPa in the steady state creep region did not change much except the sudden strain increase. And, no decrease of creep rate was observed upon increase of stress. Instead, the slightly invert transient creep or almost straight creep curves were observed, supporting the high friction stress. CrMnFeCoNi high entropy alloy has a stress exponent of 3.75 and the creep activation energy was calculated to be 278KJ/mole. The fracture strain increased from 1.3 to 1.6 with the decrease of stress from 96 MPa to 48MPa. The lower stress exponent along with the invert type primary creep curves strongly suggest that the creep of CrMnFeCoNi high entropy alloy at 600°C~650°C occurs by a glide controlled process.
The Effect of Silane Coupling Agent on the Properties of Natural Rubber Filled with Waste Silicon Carbide
Authors: Rattanapan Apaipan , Sapsrithong Pornsri , Tuampoemsab Surakit
Published: June 2017

The effect of a silane coupling on curing characteristics, mechanical properties, abrasion behavior and swelling behavior of waste silicon carbide filled natural rubber compounds was investigated in the concentration 3%, 6%, 9%, 12% and 15% by weight of the particles. The waste silicon carbide content in this study was fixed at 30 phr in order to reveal the influence of silane-69 used to modify silicon carbide. The rubber compounds were prepared using a laboratory two roll mill with temperature maintained at 50°C. The curing characteristics of the composites were determined and the composites were vulcanized at 160°C using a hot press. The properties of the natural rubber compounds such as modulus at 200% elongation, stress at peak, hardness, abrasion resistance and swelling behavior were studied. Results indicate that the maximum torque of the natural rubber compounds increased with increasing silane-69 content whereas the silane-69 can be used without much effect on the scorch time and cure time. Increasing silane-69 content also gives natural rubber compounds better resistance towards swelling and increases the modulus at 200% elongation, tensile strength, hardness and abrasion resistance. The dispersion morphology of silicon carbide in the natural rubber composites was observed by scanning electron microscopy. The modified particles with improved interfacial adhesion between waste silicon carbide and natural rubber. Improvement in mechanical properties of the composites was obtained.
Synthesis and Characterization of PVA/TiO2 Nanocomposite
Authors: Duchaniya R.K. , Choudhary Niresh
Published: June 2017

A thin film of polyvinyl alcohol (PVA) and nanocomposite of PVA/TiO2 have been prepared by spin coating method at room temperature. The influence of titanium dioxide nanoparticles on the structure, optical, and functional group analysis of nanocomposite of polyvinyl alcohol/titanium dioxide was studied by using X-ray diffraction analysis, UV–vis spectroscopy and FTIR (Fourier Transform Infrared Spectroscopy). As some significant amount of titanium dioxide nanoparticles were added to the synthesis process of a thin film of PVA/TiO2 nanocomposite and it was found that electronic band gap of the polyvinyl alcohol decreases from 3.94 eV to 3.04 eV, and absorption wavelength shifted towards red. For titanium dioxide nanoparticles, the calculated value of band gap is 3.24 eV. The XRD peak of the PVA/TiO2 was obtained in between the peak of the titanium dioxide nanoparticles and polyvinyl alcohol. FTIR confirms the presence of bonds Ti-O, -OH , -CH2 , -CH3 and of a carbonyl group.
Comparison of Mechanical Properties of Biocomposites between Polybutylene Succinate/Corn Silk and Polybutylene Succinate/Cellulose Extracted from Corn Silk
Authors: Likittheerakarn Suppawat , Kurdpradid Supawadee , Smittipornpun Nanthapon , Sritapunya Thritima
Published: June 2017

Corn silk (CS) is agricultural wastes with high cellulose content and polybutylene succinate (PBS) now is more interesting in production of plastic products due to be biopolymer and high flexibility but it is lack of stiffness and strength. Therefore, the goal of this work was to study the possibility of cellulose extraction from CS fiber which was characterized by Fourier Transform Infrared Spectrometer (FTIR) for using cellulose as a reinforcing filler in PBS. Moreover, the mechanical properties (e.g. flexural and impact testing) of PBS/cellulose biocomposite were investigated and compared with that of neat PBS and PBS biocomposite adding various amounts of sodium hydroxide (NaOH) treated CS. The FTIR results showed the contents of hydroxyl (-OH) and ketone (C=O) groups in extracted CS were lower than ones of virgin CS. It was indicated that hemicellulose and lignin were more removed during extraction process, finally obtained ‘cellulose’. For mechanical testing, both cellulose and treated CS filled in PBS affect the decreased impact strength of PBS biocomposites while flexural strength and flexural modulus were increased. Furthermore, the flexural properties were reduced with enhancing filler contents from 1-15 phr for both fillers. By comparison, the flexural properties of PBS/cellulose were slightly lower than that of PBS/treated CS whereas its impact property was quite higher, especially for 10 phr cellulose loading. Therefore, cellulose can be taken more advantage for composite production by ductile property retention of PBS compared with treated CS. In addition, both cellulose and treated CS can be use as reinforcing filler for polymer to improve stiffness and strength.
Effects of Levan on the Biodegradability and Thermal Properties of Polybutylene Succinate
Authors: Manatsittipan Sukantika , Kuttiyawong Kamontip , Tiptipakorn Sunan
Published: June 2017

In this study, the biodegradability and the thermal properties of PBS and levan were prepared in the internal mixer with levan contents of 0, 0.5, and 1 wt%. The results from Differential Scanning Calorimetry (DSC) present that the melting temperature of PBS was slightly decreased with increasing levan contents. That means there was no significant effect of levan on melting behavior of the composites at the added content. From the TGA thermograms, it could be seen that there was no significant effect on the thermal stability when adding levan. The degradation temperature at 5% weight loss for all composites were in the rage of 377-379 oC. Furthermore, char yields for all contents were closed to zero. Moreover, the water absorption of PBS/Levan composites was increased with levan content. The biodegradation was observed after 4-day burial period; the holes from degradation were larger with levan contents.
Study the Interaction Mechanism and Mechanical Properties of PVA/HA by a Molecular Dynamics Simulation
Authors: Yang Ming Ming , Wang Ya Nen , Wei Qing Hua , Chai Wei Hong , Wei Sheng Min
Published: June 2017

To investigate the interaction mechanism of PVA on the surface of HA, the molecular dynamics simulation was applied to simulate and calculate the binding energy between PVA of different monomers and HA crystallographic planes (001), (100) and (110), and then the mechanical properties and radial distribution function of the PVA/HA(110) system were calculated and analyzed. The results show that HA (110) has the higher binding energy with PVA than that of HA (001) and (100). The binding energy and the Young’s modulus of HA(110)/PVA system increase with the rising of PVA monomer number at the same crystallographic plane in a certain range, however, the descending trend takes place while monomers number reaching a certain value. This change trend is relating to the effective contact between two single components. By calculating the pair correlation function of HA(110)/PVA, there is a strong interaction between HA crystallographic plane (110) and PVA, it is mainly derived from the hydrogen bonds between O atoms of PVA and H atoms in HA crystal, besides, the ionic bonds interactions existing between OaandCa.
A Systematic Testing Procedure to Investigate the Influence of Oxide Morphology, Composition and Thickness on Changes in the High Temperature Oxidation Kinetics of AISI 316L Stainless Steel
Authors: Graham Jordan , Malinov Savko , Douglas Roy , Stalker Rose Mary
Published: June 2017

A systematic testing procedure has been employed to investigate the high temperature oxidation kinetics of AISI 316L. Thermo-gravimetric (TG) analysis was carried out at 950°C, 1050°C, 1150°C and 1250°C for 8h. Alongside this, isothermal furnace treatments were carried out on samples of the same material at the same temperatures for time periods of 0.5h, 1h, 2h, 4h and 8h. Changes in oxidation kinetics were observed on mass gain curves plotted from data derived from the TG analysis. When a change in oxidation kinetics was identified, the structure, thickness and composition of the oxides formed on the isothermal treatment samples at time periods before and after the change occurred could be studied. It was found that this systematic testing procedure provided a great deal of useful information allowing more meaningful conclusions to be made on the influence of oxide layer thickness, structure and composition on high temperature oxidation kinetics.
Mechanical and Morphological Properties of Poly(Butylene Succinate)/Poly(Hydroxybutyrate-co-Hydroxyhexanoate) Polymer Blends: Effect of Blend Ratio and Maleated Compatibiliser
Authors: Thirmizir Mohd Zharif Ahmad , Hazahar Muhammad Dzulakmal , Mohd Ishak Zainal Arifin
Published: June 2017

Poly(butylene succinate)/Poly(hydroxybutyrate-co-hydroxyhexanoate) (PBS/PHBHH) blends were prepared using melt blending in an internal mixer at 160°C. Mechanical and morphological properties of the blends, with ratios of 10/90, 20/80, 30/70, 40/60 and 50/50, are studied by tensile test and microscopy analysis. The effects of maleated PHBHH (PHBHHgMA) compatibiliser on the blend’s mechanical and morphological properties are also investigated. The compatibiliser is prepared by melt grafting maleic anhydride (MA) onto PHBHH at 160°C, in the presence of dicumyl peroxide (DCP) initiator. In this study, the purified compatibiliser is added to the blends. The highest tensile strength was achieved by the 10/90 blend, with a value of 24.83MPa; which is slightly higher than the neat PBS. The tensile modulus of the blends decreased with increasing PBS ratio, and approximately followed the Rule of Mixtures. Meanwhile, the elongation at break achieved its optimum value at 10wt. % PBS loading. The addition of PHBHHgMA at 5wt. % improved the tensile properties of all blends; with the highest value being achieved by the 10/90 blend ratio. Morphological observation via SEM was conducted to observe phase morphology and compatibility between the blend’s components.
Mechanical Properties of PM CNT-Dispersed Cu Composite
Authors: Imai Hisashi , Kondoh Katsuyoshi , Umeda Junko
Published: June 2017

Microstructural and mechanical properties of powder metallurgy (PM) with carbon nanotube (CNTs) dispersed copper (Cu) composites were investigated in detail. Pure copper powder was coated with un-bundled CNTs by using the zwitterionic surfactant solution containing CNTs. The powder rolling process was applied to increase the powder surface area to be coated with CNTs. The total rolling reduction of Cu-CNT composite powder by 5 steps rolling was about 75%. With increasing the number of rolling steps, the content of CNTs coated on the Cu powder surface increased because of the increment of the flat surface area of flaky Cu rolled powder. As a result, the CNT content was 0.67mass% after 5 steps powder rolling. It was about twice as that of as-coated Cu-CNT composite powder without rolling. The grain size of PM extruded Cu-CNT composite was about one fifth of that of the extruded monolithic Cu material without CNT. Yield stress of the extruded Cu-CNT composite via the rolling process was 192 MPa, which is about twice that of the extruded monolithic Cu material (88 MPa). CNTs distributed at primary particle boundaries were effective to prevent the grain coarsening by their pinning effects, and this grain refinement was the main strengthening factor of the Cu-CNT composite via rolling process.
Partial Characterisation and Colorimetric Characteristics of Sargassum sp. Colorant on Treated Polyester Fabric with Dendrimer
Authors: Ab Kadir Muhammad Ismail , Ahmad Mohd Rozi , Ismail Asmida
Published: June 2017

This study focuses on the characterization of pigment compounds presence in Sargassum sp. extracts. The ground powder of dry Sargassum sp. was macerated in in methanol solution at 60°C for 48 hours in an aluminium foil-wrapped conical flask (to provide the dark environment). The extracted colourant was measured with UV-vis Spectrophotometer and Q-TOF LCMS to determine the compounds presence. The extracted colourant also used to dye pretreated and untreated polyester fabric with poly(amidoamine) dendrimer at different concentrations with and without mordants. The exhaustion dyeing with the simultaneous mordanting procedure was carried at 85°C for 60 minutes. The colorimetric properties of the dyed fabrics were then analysed. The results showed that the pigment compounds presence in Sargassum sp. extracts is fucoxanthin and chlorophyll. The application of dendrimer improved K/S values of the dyed fabric. Thus, Sargassum sp. extract is suitable to be used as natural dyes for textile dyeing.
MWCNT from Carbon Black: Effect of Current Variation and Arc Application Time
Authors: Arora Neha , Sharma Niti Nipun
Published: June 2017

Carbon black can be used as a raw material to synthesize multi walled carbon nanotubes (MWCNTs). The present study focuses on synthesis of MWCNTs from carbon black using pulsed arc discharge method in Argon atmosphere. The morphological changes during conversion from carbon black to carbon nanotubes by varying arc current and arc application time is investigated. Scanning Electron Micrographs of the deposited carbon nanostructures suggest that MWCNTs are formed at 40A and for a minimal exposure time of 60sec.As we kept increasing arc current the granular structure of Carbon black transform to flakes structure and then to rigid rod like structure before getting finally converted to MWCNT.
Moisture Elimination of the Wet Hydrogen Gas Using the Electrochemical Hydrogen Compressor with a Modified MEA Composition
Authors: Jeong Ha Yeon , Jeon Sol Ah , Jeong Hyo Nam , Go Sun Ho , Lee Min Sang , Kim Hong Gun
Published: June 2017

The electrochemical hydrogen compressor (EHC) is used as a moisture elimination tool for the wet hydrogen gas. As the pressure of cathode compartment increases, the moisture contents of hydrogen decrease, however, the electrochemical performance of the compression cell is deteriorated. In the high enough pressure difference conditions between anode and cathode the electrochemical performance loss results mainly from the dehydration of the proton exchange membrane. In this article the MEA (membrane electrodes assembly) is modified to keep the water molecules not only in the membrane but also in the cathode catalytic layer. Then the electrochemical performance of the hydrogen compression cell is measured with the moisture elimination ability. The variously modified MEAs are tested and the surfaces of modified electrodes are pictured by scanning electron microscope.
Characterization of Pulse Anodized Titanium Dioxide Nanotubes
Authors: Watcharenwong Apichon , Jindanant Ariya , Kajitvitchyanukul Puangrat
Published: June 2017

TiO2 nanotubes with a highly ordered structure were grown by a self-organized electrochemical anodization in the viscous organic electrolyte. The alteration pulse anodization waveforms were applied. The applied potentials were between positive of 20 V 10 min and a reverse voltage of 0 V or -5 V 20 sec. The morphologies of samples were examined using a field emission scanning electron microscope and focused ion beam field emission scanning electron microscopes (FIB-FESEM). The crystalline structures of the TiO2 nanotubes were confirmed by X-ray diffraction. The UV–Vis diffuse reflection absorption were recorded by a UV–vis spectrometer. All TiO2 nanotube samples prepared by pulse anodization technique were anatase phase and responded to UV region. The best-defined TiO2 nanotube morphology was obtained from the anodization condition: 20 V 10 min/-5 V 20 sec for 1 h. The thickness of the oxide layer increased with the increasing anodization time. All eight TiO2 nanotube samples responded to the light in the wavelength ranging from 190-360 nm which was UV region indicated the good photocatalytic property of these materials. Properties of anodized titanium dioxide nanotube from this work can be the useful indicators for the responsiveness of ultraviolet light which enhances the good property in photocatalytic process.
Research on the Dust-Capturing Capacities of Environmental Friendly Materials Based on the Typical Garden Trees and the Morphological Structure of Leaves in Suzhou
Authors: Wang Rui Ying , Yao Xin Hua , Liu Ying Ying , Guo Yu Chen , Wang Sai , Wang Bo
Published: June 2017

Air pollution is one of the most serious environment pollution. 8 typical landscape plants, in Suzhou City, were selected to quantitative study their dust-capturing capacities, and the morphological traits of their leaves were observed under a SEM (scanning electron microscope). The paper showed that there were great differences in the dust-capturing capability of garden trees, and the dust-capturing capacities of garden trees in different seasons were in the order of May > August > November; the leaves of Cinnamomum camphora (L.) Pres, Camellia japonica L. and Euonymus japonicus Thunb. var. Ovatus Aureus had smooth surfaces or tubercles, whose dust-capturing capacities were poor, while the leaf of Loropetalum chinense(R.Br.) Oliv.Var. rubrum Yieh had many wrinkled form of cuticle, deep grooves, trichomes and high stomata desity which were favor of dust-retained, thus its dust- capturing capacity was stronger. The results can be seen as a possibility of select suitable species for urban environment.
Experimental Study of Inner-and-Outer Steel Flanges Subjected to Tension and Bending Loads
Authors: Xue Bing , Chen Yong , Chen Cong , Wang Ji Yang
Published: June 2017

Inner-and-outer steel flange has gained many attentions in China. This type flange has both inner and outer rings, as well as bolts. To gain insight into the intrinsic characteristics of the flange, an experimental study is conducted, taking into account that the tension and bending loads are imposed simultaneously. The varying of relative displacement between two adjacent flange planes with external loading is surveyed. It is indicated that the deformation is almost linearly increased with the external loads, if there is no yielded bolt. Strain gauges are employed to capture the strain distribution in the ribs as well as the tube. The internal tension force of bolt is also measured in the test. It is revealed that the failure mode of the flange is the breaking of the outer bolts. Moreover, the existence of the tension load would reduce the bending bearing capacity of the flange, and prying force could be ignored. It is concluded that the plane-section assumption holds approximately. Accordingly, formulas are given to compute the bearing capacity of the flange. It is found that the computing method is quite conservative if the position of rotation axis takes a value of 0.8 times of the diameter of the steel tube.
Relaxation of Structural Concrete due to its Shrinkage in Terms of Age-Adjusted Effective Modulus Method
Authors: Zvolánek Lukáš , Terzijski Ivailo
Published: June 2017

This paper focuses on the calculation of residual stresses due to shrinkage with a tensile creep effect. Whereas the shrinkage of concrete causes stresses in the material, the tensile creep counteracts the shrinkage as a stress relaxation mechanism. The main objective of this paper is to evaluate the ageing coefficient c (referred to as Trost-Bazant Coefficient) reflecting the load history. The coefficient is used for the residual stress analysis by means of a simplified method called Age-adjusted Effective Modulus Method. The tensile creep effect was evaluated according to the rheological model provided by Eurocode 2. Although the Eurocode predicts the creep for the structural members subjected to compressive stresses, this study proves that it can be used for the tensile creep prediction as well. We tested three types of concrete: reference concrete, high-performance concrete with reduced shrinkage magnitude by means of special admixtures, and fibre concrete with the content of polypropylene fibres. From the obtained results, it can be stated, that the ageing coefficient can be considered to be the value of 0.45 for any shrinkage development. It was also proved, that the tensile creep value essentially affects the magnitude of residual stresses, even in the “early age” concrete. The correctness of the calculated residual stresses was verified by means of a Ring-test.
Air Quenching of Steel Slag to Enhance its Hydraulic Activity for Recycling the Slag as Materials in Cement and Concrete Applications
Authors: Xue Peng , Yang Qi Xing , Liu Gui Qun , Han Feng Lan , Jiang Liang , Engström Fredrik , Björkman Bo
Published: June 2017

A steel slag has been treated by air granulation, in order to enhance cementitious properties of the slag. Two samples with sizes ranged 1.68-2.38mm and 212-297μm and coded as Slag A and Slag B, respectively, were chosen from the granulated slag for investigations. A sample of the original steel slag was also studied. XRD analyses indicated the formations of α-C2S, β-C2S, C2F, C2MS2, f-MgO and α-C2S, C2F, f-MgO in Slag A and Slag B, respectively. The phases in the two slag samples were quite different from the phases found in steel slag. The SEM results show a reduction of C2S sizes from 10-20μm for the steel slag to nano-scales by air quenching for Slag B. This treatment of air quenching has increased the cumulative heat of hydration to 105.35J/g measured for Slag B, almost two times greater than that of the steel slag. The study results demonstrate a high potential for utilizations of the steel slag in cement and concrete applications after the slag treatment by air quenching. The treatment may thus lead to an environmental friendly and cost-effective recycling for the steel slag. This can also contribute to the sustainable developments in the steel and cement/concrete industries.
Failure Analysis of Weld Crack of P92 Steel
Authors: Yin Shao Hua , Wei Yu Zhong , Wang Gan Gang , Liu Tian Zuo , Cheng Peng , Zhang Jian Lin
Published: June 2017

In order to find out the causes of weld cracks in the main steam pipe welded joint of a power plant, a series of relevant tests are specially formulated, which include room temperature tensile and high temperature tensile test, room temperature impact test, the crack tip metallographic observation, crack fracture scanning electron microscope observation, oxide film thickness measurement, and so on. By analyzing the metallographic photographs of the crack, the crack character is preliminarily determined. In addition, the direction of crack extension is determined by the thickness of oxide film in different parts. The crack failure mechanism has been identified. The results show that the welding heat crack occurs in 1# crack initiation position; and the crack initiation in 2# weld crack (primary crack) position is caused by the root defect of welding seam and lead to a high brittleness, which results in the crack failure by crack propagating in operational process gradually.
Anchor Spacing Design of Pre-Stressed Tunnel Concrete Lining with Un-Bonded Annular Anchors for Songhua River Water Supply Project
Authors: Pi Jin , Zhao Yu Fei , Cao Rui Lang , Jia Zhi Xin
Published: June 2017

At present, annular anchor pre-stressed tunnel Concrete lining is the main design method of poor -quality surrounding rocks, thin covering and high internal water pressure tunnel. Based on the contact of tendons and concrete, the annular anchor lining can be classified into bonded and un-bonded. Cable spacing is one of the key parameters in the design of the un-bonded annular anchors pre-stressed concrete lining. The optimal anchor spacing can not only meet the demand of the project, but also save the cost of construction. In this paper, the anchor spacing is studied in the design of pre-stressed tunnel concrete lining with un-bonded annular anchors for Songhua River water supply project. The equivalent load method and solid modeling method are combined in Flac3d 3D modeling. Numerical simulation of pre-stressed effects for different anchor spacing in tension and operation of the concrete lining were analyzed. The optimal anchor cable spacing is received, which is a reference for the design and construction of similar projects in the future.
Variation of the Modulus of Elasticity and Anisotropic Factor over the Thickness of the Bamboo Wall
Authors: Smits M.A. , Pizzol V.D. , Krüger P.V. , Rezende M.A.P. , Alves R.C. , Carrasco E.V.M. , Mantilla J.N.R.
Published: June 2017

The objective of this study is to experimentally determine the physical and elastic properties of bamboo and set the anisotropic factor along the wall thickness of the bamboo. The physical properties were determined following the requirements of the Brazilian standard. The elastic modulus was determined by non-destructive testing using the impulse excitation method. The density in the shell region is 40% larger than the inner portion. The density variation in the wall thickness of the bamboo is not linear, having a more pronounced nonlinearity in the shell region. The results of the ANOVA table indicate that shrinkage factors in bamboo wall thickness can be considered statistically the same, i.e., they do not vary with the wall thickness of the bamboo. The anisotropic factor in the intermediate and inner region can be considered statistically equal, 1.8. As for the factor measured in the region close to the bark, 2.03, it cannot be considered equal to the other regions. There is a variation of the modulus of elasticity, between the interior and the bamboo bark, of 279%.
Use of Rejuvenators to Rejuvenate Asphalt Binders in RAP
Authors: Krcmova Iva , Hyzl Petr , Nekulova Pavla , Coufalik Pavel , Dasek Ondrej
Published: June 2017

With increased demand and limited aggregate and binder supply, hot mix asphalt (HMA) producers discovered that reclaimed asphalt pavement (RAP) is a valuable component in HMA. This paper is concerned with the current issue of higher using RAP (Reclaimed Asphalt Pavement) in asphalt mixtures for pavement wearing courses. It describes the effects of application of three types of rejuvenation additives on properties of aged asphalt binders made from a regular RAP. These rejuvenation additives restore the physical and chemical properties of aged binders. In addition, the aged asphalt binder with rejuvenators applied was subjected to a short-term laboratory aging using the RTFOT (Rolling Thin Film Oven Test). This method simulate aging asphalt binder during the manufacturing process and laying. To assess the binder properties, both the standard empirical tests and more advanced functional tests (dynamic shear rheometer and bending beam rheometer) have been performed. Last part of the paper provides an evaluation of the individual rejuvenation additives. Based on the results it can be concluded that a positive change in properties of aged asphalt binder after applying all the three rejuvenators has been proven.
Prototype of Geocell from Natural Rubber: Effect of Dual-Phase Fillers on Physical Properties of Rubber Compounds Reinforced with Silica and Carbon Black
Authors: Wongwilatnurak Sompatsorn , Tuampoemsab Surakit , Dangtungee Rapeephun
Published: June 2017

Geocell, a type of the geosynthetics, is normally used to improve natural geomaterial properties and performance because of confinement and confinement force. This work was an attempt to apply the solid natural rubber (NR) for producing the prototype of geocell with reinforcing the pavement structure of the road. There are three parts of all work in research, which consist of finding the optimal chemical formula, designing and producing the prototype and civil engineering testing of flexible pavement components. This research has emphasized and focused on finding the optimal chemical formula for the prototype production. The effect of silica-carbon black (CB) dual-phase filler on physical properties in terms of only static mechanical tests of the prototype was investigated. The total amount of hybrid reinforcing filler was fixed at 60 phr while the silica/CB ratios were 0/60, 10/50, 20/40, 30/30 and 40/20, respectively. Cure characteristic of the NR compound and physical properties in terms of static mechanical tests such as hardness, tensile and tear strengths of the NR vulcanizates were carried out. The results showed that time to 90% cross-linked (TC 90), hardness and tensile strength of the vulcanized rubber were increased with the increasing of silica content but not for its tear strength. Dispersion of the dual-phase filler in the prototype was reduced when the higher amount of silica in the dual-phase filler was employed as proved by images from the scanning electron microscope. There was only 60 phr CB that was selected as the optimal chemical formula for prototype production as the result of tensile and tear strength.