bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Body Composition and Fatty Acid Profiles between Wild and Cultured Rio Grande Silvery Minnows
Authors: Powell Madison S. , Hardy Ronald W. , Hutson Alison M. , Toya Louie A. , Tave Douglas
Published: August 2017

Federally endangered Rio Grande Silvery Minnows (RGSM; Hybognathus amarus) were raised in one of three culture regimes: intensively, with only a hatchery diet; semi-intensively with access to natural food and hatchery diet supplementation; and with only natural food available at the Los Lunas Silvery Minnow Refugium (Los Lunas, New Mexico), a naturalized conservation refugium designed to mimic the natural environment of the RGSM in the Rio Grande. The project compared each culture regime and assessed differences and similarities in lipid and fatty acid content between feeding an artificial diet and consumption of natural food items in this species. After 117 d, whole-body lipid levels and fatty acid profiles were measured in each group and compared with values for wild RGSM. Fish fed the hatchery diet exclusively or as supplementary feed had significantly higher percent lipid (15.5% ± 0.5% and 10.6% ± 0.1%, respectively) than fish raised without access to the diet. Both groups had significantly higher percent lipid than fish raised in the refugium or wild fish (8.3% ± 0.1% and 7.8% ± 0.2%, respectively). Condition factor differed among groups and was highest in fish fed the hatchery diet (1.00) followed by fish supplemented with the hatchery diet (0.93), refugium fish (0.91), and wild fish (0.90). In this respect, refugium fish appeared more similar to wild fish than fish fed the hatchery diet or offered the diet as a supplement. Comparison of fatty acid profiles among groups showed marked differences among wild fish, refugium fish, and those fed the hatchery diet, either exclusively or as supplementary feed. Total omega-3 fatty acids, expressed as percentage of total fatty acids, were highest in wild fish but similar among other groups. Total omega-6 fatty acids showed an opposite trend, with five to nine times higher percentages of linoleic acid observed among fish from the three culture regimes compared with wild fish. Significant differences in lipid content and fatty acid composition between wild RGSM and cultured silvery minnows reflected their respective diets and culture regimes. Given similarities in fat content and condition factor with wild RGSM, we conclude that fish in the refugium do not require supplemental feeding with an artificial diet for this type of naturalized conservation management. Results from this study show that RGSM readily forage on natural food items present and also artificial feed when available, indicating dietary plasticity, which is advantageous for fish culture and future recovery.
Lead Poisoning in Bald Eagles Admitted to Wildlife Rehabilitation Facilities in Iowa, 2004–2014
Authors: Yaw Taylor , Neumann Kay , Bernard Linette , Cancilla Jodeane , Evans Terese , Martin-Schwarze Adam , Zaffarano Bianca
Published: August 2017

Eleven years (2004–2014) of bald eagle Haliaeetus leucocephalus data from four independent, state and federally permitted wildlife rehabilitators in Iowa were assessed for the prevalence of elevated lead levels in blood or tissue samples. The relationship between blood lead concentrations and recorded information (age, season, radiographs, and clinical outcome) was investigated. Adult birds had higher blood lead concentrations than immature and juvenile birds. Highest blood lead levels were found during October–January. Bald eagles with positive radiographs for metallic opacities in the digestive tract had higher blood and tissue lead concentrations than those with negative results or those on which no radiograph was performed. Metallic opacities were identified through necropsy. Bald eagles with elevated levels of lead were associated with poor clinical outcomes, indicating that blood lead concentrations could be used as a predictor of clinical outcome.
Microstructure and Corrosion Properties of Homogenized AZ31 and AZ31+1%La Magnesium Alloys
Authors: Ahlatci Hayrettin , Kara Ismail Hakkı , Turen Yunus , Sun Yavuz , Zengin Huseyin
Published: August 2017

Energy efficiency and decreasing emission of greenhouse gasses emerge that the importance of Mg alloys. Mg alloys can begin to supersede the steel and aluminum for structural applications, thanks to the developing of mechanical properties or corrosion resistance of Mg alloys. Rare earth metals such as Gd, Ce, Y and Nd have been utilized at AZ31 Mg alloys for this purpose in recent years. In this study, the effects of La addition and homogenization heat treatment on microstructure, hardness properties and corrosion resistance of AZ31 and modified AZ31 Mg alloys produced by low pressure die casting method were investigated.
Calcium Oxalate on Limestone Surface of Heritage Buildings
Authors: Ion Rodica Mariana , Teodorescu Sofia , Ştirbescu Raluca Maria , Bucurică Ioan Alin , Dulamă Ioana Daniela , Ion Mihaela Lucia
Published: August 2017

In this paper, the presence of calcium oxalate on calcareous stone, is studied. The patina consists mainly of calcium oxalate which exists in three forms: monohydrated whewellite (small, smooth, globular yellow-green to brown crystals radial fibrous) (COM), dehydrated weddelite (small crystals, and spherical clusters of plaques consisting of brown or yellow platelets, which are sharp) (COD) and trihydrate caoxite (rarely observed, as mono or dihydrated precursor forms)(COT). Scanning electron microscope with Energy Dispersive X-ray Spectroscopy (SEM/EDS), Fourier Transform Infrared spectroscopy (FTIR), Raman Spectroscopy are used for characterization. The oxalate films were found to form a thin compact non-porous shell and penetrate deeply in an intergranular position or along microfractures, with effects on longer stability.
New High Entropy Alloy for Biomedical Applications
Authors: Ghiban Brandusa , Popescu Gabriela , Dumitrescu Daniela , Soare Vasile
Published: August 2017

High Entropy Alloys (HEAs) represent a new concept of metallic materials, that contain 5 or more elements, in proportions from 5 at.% to 35 at.%, and form simple solid solutions (BCC and/or FCC) instead of complicated intermetallic phases. The high degree of randomness atomic HEA, gives them excellent properties: electrical, mechanical, electrochemical, ductility, anti-corrosion properties, stable structure etc, with applications in peak thus representing a growing research. These specific features provides HEA with excellent hardness, strength and wear strength, malleability, oxidation and corrosion resistance, with potential applications in diverse industrial areas [1÷4]. Considering these properties we decide to improve biomedical alloys with this new class of HEAs.
Structural Aspects Revealed by X-Ray Diffraction for Aluminum Alloys 2024 Type
Authors: Anghelina Florina Violeta , Ionita Ionica , Ungureanu Dan Nicolae , Stoian Elena Valentina , Popescu Ileana Nicoleta , Bratu Vasile , Petre Ivona , Popa Carmen , Negrea Alexis
Published: August 2017

This paper presents experimental results revealed on the samples type 2024 aluminum alloy used in aeronautics. Adequate characterization of 2024 aluminum alloys with special destination (aviation) was achieved by combined investigations:(i) wet chemical analysis, (ii) spectrochemical analysis, (iii) X-ray diffraction and (iv) electron microscopy. The main conclusion that emerges from the investigations carried out on aluminum samples revealed that: (a) alloys fits in terms of composition with the standard specification for 2024, in all cases; (b) microstructure vary in fineness of grain, but meets the requirements of aviation rules; the investigated microstructures have been appreciated as adequate of aluminum alloys type "2024".
Effect of TIG Welding and Manual Metal Arc Welding on Mechanical Properties of AISI 304 and 316L Austenitic Stainless Steel Sheets
Authors: Harb Alaa Abu , Ciuca Ion , Ciocoiu Robert , Vasile Mihai , Bibis Adrian , Rahali Bilel , Al Hawamda Ismaiel
Published: August 2017

The welding technique used for ASIS 304 and 316L austenitic stainless steel sheets both with a thickness of 3mm is gas tungsten arc welding (TIG) and manual metal arc welding (MMAW). Mechanical properties that were verified include: hardness test and tensile test before welding and after it. The welding process was done on two types of specimens: with a central hole and without hole. We concluded that there was a decrease in the properties of tensile for both specimens with central hole, and 316L had tensile characteristics better than 304 when using the technique TIG. As for 304, it had tensile characteristics better than 316L when using the technique MMAW. We also concluded that the existence of central holes had an influence on the hardness characteristics on both types. The hardness increased in 304 but decreased in 316L. The welding process also showed that there was no influence of MMAW on hardness on both specimens. However it showed that there was no influence of TIG on the hardness for 304, but for 316L values increased.
Advanced Synchrotron Radiation and Neutron Scattering Techniques for Microstructural Characterization in Industrial Research
Authors: Fiori Fabrizio , Girardin Emmanuelle , Giuliani Alessandra , Manescu Adrian , Mazzoni Serena , Rustichelli Franco , Amler Evzen
Published: August 2017

The rapid development of new materials and their application in an extremely wide variety of research and technological fields has lead to the request of increasingly sophisticated characterization methods. In particular residual stress measurements by neutron diffraction, small angle scattering of X-rays and neutrons, as well as 3D imaging techniques with spatial resolution at the micron or even sub-micron scale, like micro-and nano-computerized tomography, have gained a great relevance in recent years.Residual stresses are autobalancing stresses existing in a free body not submitted to any external surface force. Several manufacturing processes, as well as thermal and mechanical treatments, leave residual stresses within the components. Bragg diffraction of X-rays and neutrons can be used to determine residual elastic strains (and then residual stresses by knowing the material elastic constants) in a non-destructive way. Small Angle Scattering of neutrons or X-rays, complementary to Transmission Electron Microscopy, allows the determination of structural features such as volume fraction, specific surface and size distribution of inhomogeneities embedded in a matrix, in a huge variety of materials of industrial interest. X-ray microtomography is similar to conventional Computed Tomography employed in Medicine, allowing 3D imaging of the investigated samples, but with a much higher spatial resolution, down to the sub-micron scale. Some examples of applications of the experimental techniques mentioned above are described and discussed.
Stainless Steels as Erosion Resistant Materials for Hydraulic Machines
Authors: Ghiban Brandusa , Safta Carmen Anca , Motoiu Vlad
Published: August 2017

The corrosion phenomena lead to serious modifications in the structure of metallic materials from which are manufactured the important active components of hydraulic machines. There are two important types of corrosion: cavitation and silt erosion (abrasive erosion), that are specific to machines which are producing energy [1, 2, 3]. As a corrosion mechanism, in hydrodynamic cavitation [4, 5], when cavitation bubbles implode on the solid surface of hydraulic machine component, the local pressure developed is high and can exceed the fatigue strength, yield point or compression strength of the material. Cavitation phenomenon can be produced in different ways. Four types of cavitation are described in the literature, looking for the method of producing, [6]: hydrodynamic cavitation, particle cavitation, acoustic cavitation, and optic cavitation. Abrasive erosion is the gradual degradation of a structure under the action of solid particles suspended in the working fluid. Impact and sliding erosion are the main categories of abrasive erosion approached in the literature by considering the mechanisms of which the abrasive particles act on the metallic surface, [2]. In the last decades the abrasive erosion phenomenon became a serious problem for the efficient operation of power plants, for instance in hydropower plants [7, 8]. Geothermal energy is the heat energy of the earth given by capturing the springs of heat water. In Romania the geothermal energy is used only for heating because the water has a low temperature and cannot be used to produce electric energy, only heat energy. So, although Romania is the third highest potential geothermal in Europe, practically electric energy from geothermal resource has a low thermal potential, [9]. A steam turbine is working at high rotational speed, high temperatures and using the working fluid which could be steam or wet steam. The working fluid is composed of corrosive chemicals with an aggressive pH. For this reason the common problems of the geothermal steam turbine failures are given by fractures of the blades (rotor blades or stator blades).
Effect of Ionic Liquid Environment on the Corrosion Resistance of Al-Based Alloy
Authors: Peter Ildiko
Published: August 2017

Electrodeposition of Al and its alloys from ionic liquids has been extensively investigated during the years and has received significant consideration as non-aqueous electrolytes for the electrodeposition. As environment-friendly solvents, ionic liquids have also good prospective to substitute the old-style risky solvents. In this paper, the results obtained after monitoring of some Al based materials involved in the deposition process and in a real contact with chloride and ionic liquid rich environment are presented and discussed.
Corrosion Behavior of Al-Zn-In Sacrificial Anode Alloys Produced by Conventional Casting and Semi-Solid Metal Casting Processes
Authors: Puridetvorakul Chanika , Poolthong Nuchthana , Tareelap Napachat
Published: August 2017

A challenge in producing a sacrificial anode through conventional casting method is that the alloying elements in casting segregate during solidification, which further causes non-uniform anode corrosion reducing anode performance. In this paper, we investigated the performance of Al-5Zn-0.02In anode produced by conventional casting compared with by semi-solid casting technique. The performance of produced anodes were measured in terms of anode potential, current capacity, consumption rate and anode efficiency in 3.5% NaCl solution for 14 days. We found that the microstructure of the conventional cast anode had dendrites and coarse grains and the corrosion caused pitting corrosion. In contrast, the semi-solid cast anode had fine grains without any dendrites. The corrosion attacked mainly the grain boundaries and less on the matrix. Surprisingly, the conventional cast anode has about 10% higher efficiency than that of semi-solid cast anode.
Development of Pitting Corrosion Monitoring Device under Sodium Chloride Droplet by Means of Wet-Dry Cyclic Method
Authors: Banthukul Wongpat , Sathirachinda Palsson Namurata , Viyanit Ekkarut , Rodchanarowan Aphichart
Published: August 2017

Pitting corrosion caused by wet-dry cycles under corrosive media droplet is one of the key concerns for passive film of metallic materials, particularly stainless steels and aluminum alloys, exposed to atmosphere during service. In this context, the formation of corrosion can lead to high investment cost dealing with corrosion mitigation strategy, e.g. materials selection, electrochemical corrosion control, etc. Based on materials selection perspectives, it is very necessary to have proper understanding of localized corrosion behaviors of metallic materials under solution droplet. Therefore, the present study aims to develop a methodology for pitting corrosion monitoring that can be suitably used for extending better understanding on corrosion phenomena occurring under wet-dry cycles of droplet. A special liquid handling apparatus controlled by Arduino software was constructed and used for generating NaCl solution droplet at given dimension on the surface of stainless steel specimens based on Pendant drop principle. This was recognized as wet cycle. During dry cycle, such NaCl solution droplet was naturally dried off in various conditions of relative humidity. Pitting initiation was observed through a high-resolution CCD camera. Droplet morphology and evaporation time were evaluated at the temperature of 27°C and relative humidity of 10% and 60%. The research results revealed that pitting corrosion started at 1st cycle without rust formation. Afterwards, the rust formation was clearly noticed when testing cycles of 15 were exceeded.
Factors Affecting on the Corrosion Resistance of Electroless Ni-Zn-P Coated Steel
Authors: Rattanawaleedirojn Pranee , Saengkiettiyut Kanokwan , Boonyongmaneerat Yuttanant , Wanichsampan Jumpot
Published: August 2017

Electroless Ni-Zn-P coating with the optimal content of Ni and Zn in the alloy provides high corrosion resistance for steel. Ni-rich phase of this high hardness Ni-Zn-P alloy offers barrier protection property and sacrificial protection property is obtained from the alloy with proper content of Zn. In this work, the Ni-Zn-P coatings were prepared on steel substrates by using alkaline electroless deposition. The parameters of deposition process including complexing agent concentration, bath pH, zinc ion and nickel ion concentration were systematically studied. The microstructural morphology and elemental composition of the coatings were characterized by scanning electron microscopy. It was found that complexing agent, zinc ion and nickel ion concentrations play important role on Zn content of Ni-Zn-P alloy whereas alkalinity of the solution bath directly affects the deposition rate. The results of corrosion resistance investigated by linear polarization illustrate that the corrosion potential (Ecorr) of Ni-Zn-P coatings is negatively shifted by an increase of Zn content in the alloys. From this work, Ecorr of 83%Ni-11%Zn-6%P coating prepared in this system is slightly lower than steel. To achieve a higher effect of sacrificial protection for corrosion protection of steel, Ni-Zn-P with higher content of Zn should be further studied.
Effect of Si Content on Mechanical Properties of Ti-Si-N Ternary Alloys Prepared by Spark Plasma Sintering
Authors: Khemglad Patcharawat , Kajornchaiyakul Julathep , Kondoh Katsuyoshi , Khantachawana Anak
Published: August 2017

In the present work, the strengthen mechanism of Ti-Si-N ternary alloys prepared by Spark Plasma Sintering (SPS) was investigated. Ti, Si and TiN substrate powders were prepared in order to obtain nominal composition of Ti-0.35Si-1TiN and Ti-0.7Si-1TiN (wt %). Homogenization was performed before extrusion. Microstructure and phase identification were analyzed by Optical Microscope (OM) and X-ray diffraction (XRD). In order to evaluate the mechanical properties of extruded specimens, micro hardness test and tensile test were carried out. The XRD results show that no Si and TiN particles are remained after SPS and no any reaction caused of intermetallic compound during heat treatment and extrusion processes. It is found that the abnormal phase with high N-content was observed in matrix phase. It is also obvious that increasing Si from 0.35Si to 0.7Si (wt %) can increase yield stress and ultimate tensile stress from 1006±15 to 1092±5 MPa and 1089±10 to 1170±10 MPa, respectively. Hence, the strengthening mechanism by addition Si content into Ti-1TiN (wt %) is only solid solution mechanism.
Meta-Heuristics for Engineering Optimisation - Applications to Metal Forming Processes
Authors: Pholdee Nantiwat , Bureerat Sujin
Published: August 2017

This paper presents the use of meta-heuristics one of the most popular types of optimisation methods for solving real engineering applications. The general procedure of meta-heuristics is detailed. The applications are related to metal forming processes. Two design examples, optimisation of a strip coiling process and the non-circular wire drawing process, are demonstrated. The results obtained are compared while advantages and disadvantages of using the optimisers are discussed.
Morphology and Properties of Polyoxymethylene/Polypropylene/Microcrystalline Cellulose Composites
Authors: Yasumlee Nipawan , Wacharawichanant Sirirat
Published: August 2017

The effects of microcrystalline cellulose (MCC) on mechanical, thermal and morphological properties of polyoxymethylene (POM)/polypropylene (PP) blends at different compositions were investigated. The blends and composites were prepared by melt mixing using an internal mixer at 200°C. Scanning electron microscopy (SEM) analysis revealed phase separation between POM and PP phases due to the difference in polarity of POM and PP. When adding the MCC in the blends the morphology slightly changed due to the weak interaction between MCC and polymer phases. Incorporation of MCC at 5 phr could improve Young’s modulus of POM/PP blends. The storage modulus of the blends was improved after adding MCC 5 phr due to reinforcing effect of the MCC. The thermal properties found that the addition of MCC had no effect on the melting temperature of the blends. The blends exhibited higher decomposition temperature than pure POM. The blends showed the decomposition temperatures increased when increasing amount of PP content, which were higher than pure POM. Therefore, it may be inferred that the addition of PP could enhance the thermal stability of the POM/PP blends, but the addition of MCC did not improve the thermal stability.
Preparation of TiO2/WO3 Composite Nanofibers by Electrospinning
Authors: Chakornpradit Patthamapa , Phiriyawirut M. , Meeyoo Vissanu
Published: August 2017

Preparation of cellulose acetate (CA)/TiO2/WO3 composite nanofibers via sol-gel with electrospinning process for improving the photocatalytic efficiency was conducted. CA was removed from fibers by a heat treatment. Microstructure and elemental composition of TiO2/WO3 nanofibers were evaluated by scanning electron microscope (SEM) and energy dispersive microscopy (EDX), respectively. The results showed that the nanofibers of TiO2 and WO3 were achieved with the average diameter range of ca. 310-701 nm and both TiO2 and WO3 are well dispersed along fiber length, confirmed by an EDX analysis. The results also showed that the smoothness of fiber surface decreased with decreasing WO3 contents. The photocatalytic activity of the materials were also tested for methylene blue degradation. TiO2/WO3 exhibited the highest activity comparing to pure TiO2 and WO3. Moreover, it was found that a TiO2/WO3 specimen possessed the energy storage ability as a result, it showed the photocatalytic activity in the absence of light.
Effect of Poly(Hexamethylene Succinamide) on Crystallization of Poly(L-Lactic Acid)
Authors: Yueagyen Panadda , Lertworasirikul Amornrat
Published: August 2017

Poly(L-lactic acid) (PLA) has good mechanical properties and is biodegradable. However, its crystallization rate is slow, crystallization period long, and its crystallization temperature high at 116 °C. Consequently, long processing cycles are required for the production of high crystallinity poly (L-lactic acid). Addition of nucleating agents is an efficient way to solve this problem. Aliphatic amide such as N,N-ethylenebis(12-hydroxystearamide) and ethylenebis-stearamide are reported as nucleating agents for poly (L-lactic acid). In this study, the effect of the aliphatic polyamide, poly (hexamethylene succinamide) on the crystallization behavior of PLA was investigated. Poly (hexamethylene succinamide) was synthesized by melt polymerization. Between one and ten weight percent poly (hexamethylene succinamide) was blended with poly (L-lactic acid) by melt extrusion. The crystallization temperature and crystallization period decreased with increasing poly (hexamethylene succinamide) content. The degree of crystallinity increased with the addition of poly (hexamethylene succinamide). A poly (hexamethylene succinamide) content of 5%wt provides optimum conditions for production of poly (L-lactic acid)-poly (hexamethylene succinamide) blend with good mechanical properties. The polymers obtained are entirely from renewable resources.
The Effect of Bottom Ash Additions on the Properties of Sintered Bronze-Graphite Composites
Authors: Pantulap Usanee , Auechalitanukul Chiraporn , McCuiston Ryan C.
Published: August 2017

The aim of this research was to study the effect of bottom ash additions to a bronze-graphite composite on the sintering behavior, as well as on the resultant physical, mechanical and tribological properties. The composites were produced by a powder metallurgy technique from prealloyed Cu-10Sn bronze powder, graphite powder and milled bottom ash powder. The compositions studied were Cu-10Sn bronze with constant 5 wt.% graphite, and 0-20 wt.% bottom ash. Samples were die compacted under 795 MPa and sintered at 850 oC for 30 minutes in an open atmosphere furnace. It was found that the sintered density of the composites decreased with increasing amounts of bottom ash. The hardness of the samples increased with bottom ash additions and reached a maximum at 5 wt.% and decreased with further additions. The frictional properties were studied using a ball-on-disc test at ambient temperature. It was found that both the friction coefficient and the wear rate were increased with increasing amounts of bottom ash.
Degradation Test of Natural Rubber/Chitosan Composite
Authors: Sukthaworn Chalermchat , Reowdecha Manuchet , Dittanet Peerapan , Moonprasith Nantina , Lampang Thipjak Na , Loykulnant Surapich , Prapainainar Paweena
Published: August 2017

Degradable materials from 20wt% chitosan loading and natural rubber (CS/NR) were prepared by solution casting without surface treatment to study their thermal and mechanical properties after degradation test in aging condition. The test was done in an acrylic degradation box with 600 W light and high humidity for accelerate degradation condition. Samples included high ammonia concentrated latex (HA) with no filler, fresh latex (FL) with no filler, HA with chitosan filler, FL with chitosan filler, and natural rubber with shrimp shell filler to compare the result with chitosan filler. After degradation test, thermal properties from TGA both before and after degradation showed that the fillers effected on these composite materials. TGA result of CS/NR composite with aging at temperature 100 °C for 10 h and 20 h showed that chitosan slightly effected on thermal stability of composites when compare to natural rubber. SEM images were compared before and after degradation of HA and FL with no filler, chitosan filler, and shrimp shell. It was clearly seen that the samples degraded as the shape and size were changed. Tensile testing values showed that longer aging time could lead to the degradation in CS/HA and lower the tensile strength.
Low Haze and Antifog Performance of 2-Layer Poly(Lactic Acid) Based Films
Authors: Liewchirakorn Pitcha , Suthisamphat Pumpanchat , Chinsirikul Wannee , Aht-Ong Duangdao
Published: August 2017

For fresh-cut and ready-to-eat packaging films, antifog additives (AFs) are commonly used to suppress the formation of water droplets on film surface. To date, the type and dosage of antifogging for PLA based film are less studied. Therefore, in this research, films incorporated with antifog additive were fabricated by cast extrusion technique. The migration behavior of commercial polyglycerol ester as selected AF was investigated. The cold fog test results showed that 3.5 and 5 wt% of AF in 20PBAT/80PLA single layer film can provide clear films without droplet of water within 7 days and 3 hours, respectively. For 2-layer films, the presented of AF in seal layer as 95(20PBAT/80PLA)/5 (polyglycerol ester) and core layer of PLA were prepared having different thicknesses of seal layer/core layer of 20/15 and 10/15 μm. The migration rate of AF in thin 2-layer film (10/15 μm) appeared to be higher than that in 20/15 μm film. Films’ surface could become clear without water droplet (rating scale > 8) within 4 days for 10/15 μm and 7 days for 20/15 μm films. Haze of films was analyzed by haze meter. Haze of 10/15 μm film was decreased from 7 to 4.4, while that of 20/15 μm film was also decreased from 10 to 7.9 when AF appeared on its surface. Both films can be a peelable PLA based lidding film product with low haze (< 10 %) and antifog performance (within 1 month). In addition, 10/15 μm film can be an easy peel lidding film since its peel strength was in an easy peel range (6-10 N/15 mm).
Fabrication of Low Cost Membrane from Anodic Aluminum Oxide
Authors: Sumtong Peerawith , Eiad-Ua Apiluck
Published: August 2017

Anodic Aluminum Oxide (AAO) membrane has been successfully fabricated from two-step anodization with aluminum low grade (Al6061). The pore density, the pore diameter, and the interpore distance can be controlled by varying anodization process conditions. However, there are limits to control the mechanical strength and growth of AAO arrays, such as pore density, pore diameter and interpore distance. In this research the self-organized two-step anodization is carried out varying time at 24, 48 and 72 hours, respectively with 40V at the low temperature 2-5°C. The optimum conditions of AAO with two-step anodization is 40V for 48 hr. Finally, AAO substrate is separated from aluminum low-grade and enlarged pore diameter with pore widening process by 5% H3PO4. The physical properties were investigated by mean of field emission scanning electron microscope (FE-SEM) show that the average pore diameter and average interpore distance increase with the anodization time. Al6061 Aluminum substrate can be used to fabricate a nanoporous AAO film with an average pore diameter and average interpore distance larger than 70 and 90 nanometers, respectively but less mechanical stability.
Piezoelectric and Ferroelectric Properties of KNbO3 Added Bi0.5Na0.5TiO3 Ceramics
Authors: Kantha Puripat , Raksa Phathaitep , Unruan Muangjai , Tunkasiri Tawee , Jaiban Panupong , Pisitpipathsin Nuttapon
Published: August 2017

The fabrication of lead-free (1-x)Bi0.5Na0.5TiO3 - xKNbO3 or (1-x)BNT-xKN ceramics where x = 0.00, 0.05, 0.10, and 0.15 was carried out by the modified two-step mixed oxide method. The effects of KNbO3 on structure, piezoelectric and ferroelectric properties were systematically investigated. XRD results revealed that the (1-x)BNT-xKN ceramics with low KN content of x less than 0.05 contained ferroelectric phase with a rhombohedral symmetry while the ceramics with x = 0.05 possessed pseudocubic structure. The higher KN content (x ≥ 0.10) ceramics had symmetries rhombohedral structure. At room temperature, the highest Pr and low Ec were obtained when the composition of x = 0.05. Moreover, the results showed the moderate KN addition could enhance the piezoelectric response. The d33 of 0.95BNT-0.05KN reached as high as 125 pC/N.
Effects of Ball Milling on the Properties of (Ba1-xCax)(Ti0.92Sn0.08)O3 Lead-Free Ceramics
Authors: Wattanapradit Onchuda , Bomlai Pornsuda
Published: August 2017

The (Ba1-xCax)(Ti0.92Sn0.08)O3 (x = 0 and 0.02) lead-free ceramics were prepared by using different ball-milling method and time (common ball milling 24 h, high energy ball milling 1 and 3 h). The two-step sintering method was used for sintered the samples. The densification, structure, dielectric and piezoelectric properties of the ceramics were investigated. The results showed that Ca addition could reduce sintering temperature effectively and enhanced densification at lower temperature when using the common ball-milling type. The XRD patterns of (Ba1-xCax) (Ti0.92Sn0.08)O3 ceramics revealed the change in crystal symmetries from tetragonal to cubic phase with increasing Ca content from 0 to 0.02. However, the crystal structure did not change due to the effect of ball-milling method. Ca incorporation caused a decrease of the grain size and Curie temperature. Moreover, the largest grain size was found in the x = 0 ceramics with 24 h-common ball-milling, whereas the small size (< 5 µm) was obtained for the x = 0.02 ceramics. The dielectric and piezoelectric properties were also affected to Ca addition and ball-milling. High piezoelectric coefficient of d33 = 173 pC/N, dielectric constant εr ~ 3200 and dissipation factor tand ~ 0.05 were obtained for the x = 0 sample with high energy ball-milling for 1 h.
The Effect of Calcium-Based Salt on Hydrothermal Carbonization of Corncob
Authors: Reangchim Promporn , Nakason Kamonwat , Viriya-Empikul Nawin , Eiad-Ua Apiluck
Published: August 2017

Corncob represents a great potential as a raw material for the production of high-value added chemicals, fuels and other industrial products. Thus, corncob is suitable residue for study molecular structure through the pretreatment method. In this study, the effect of calcium-based salts on the hydrothermal carbonization (HTC) of corncob were studied at 160, 180, and 200 °C for 2 h. CaSO4 and Ca3(PO4)2 were used as a reaction medium. Hydrochar was characterized by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and ATR-Fourier transform infrared spectroscopy (ATR-FTIR). Characteristics of the hydrochar varied with calcium-based salt. Cellulose crystallinity in hydrochar decreased dramatically and carbon content in hydrochar obviously increased when Ca3(PO4)2 and CaSO4 were added, respectively. In case of hydrothermal at 180°C with Ca3(PO4)2 and CaSO4, the carbon microsphere was occurred.
Charged Iridium(III) Complexes with Varied Side Chain Length in Organic Light Emitting Diodes
Authors: Wongsang Natsiri , Wongkhan Kittiya , Kangkeaw Laongdao , Sahasitthiwat Somboon , Jitchati Rukkiat
Published: August 2017

The four varied side chains of charged iridium(III) complexes were synthesized and characterized for organic light emitting diodes. The core materials were designed with 9,9-bis(4-methoxyphenyl)-4,5-diazafluorene as the bulky N^N ligand which prevent the π-π stacking interaction in the solid state. Their photophysical and electrochemical properties were investigated. OLEDs were fabricated with the structure ITO/PEDOT:PSS/ PVK:complex (10:7 by weight)/ TPBi/LiF/Al. The similar colors were obtained with varied OLEDs performances. We concluded that the long alkyl chains affected to the excellent film-forming property of emitting layer. Therefore, the device based on the n-octyl chain namely [(9,9-bis(4-octyloxyphenyl)-9H-cyclopentadipyridine-N-N′)-bis-(2-phenylpyridine-C2′,N)-iridium(III)] haxafluorophosphate (C8) showed the maximum current efficiency and brightness of 11.37 cd/A and 3,926 cd/m2, respectively.
Geopolymerization as Cold-Consolidation Techniques for Hazardous and Non-Hazardous Wastes
Authors: Leonelli Cristina , Kamseu Elie , Lancellotti Isabella , Barbieri Luisa
Published: August 2017

Many interesting studies on the utilization of wastes produced in different human activities (urban, agricultural and industrial) have been carried out with the goals to reduce, to recycle, to reuse or to recovery: the R4 strategy. Many of these waste contains high amount of silicoaluminates, making them suitable for alkali activation to become one of the most promising binders for the future. Other type of wastes, even if hazardous, such as incinerator fly ash, electric arc furnace dust, lead smelting slag, etc. can be easily added as minor components to the geopolymer matrix for being immobilized as either cations or anions or both.
Influence of Portland Cement on Physical, Mechanical and Thermal Properties of Cellular Lightweight Concrete
Authors: Thongtha Atthakorn , Ketchaona Surirat , Wattana Jutarud , Patanin Tanapon
Published: August 2017

The research in this paper aims to study the physical, mechanical and thermal properties of building wall materials (Cellular lightweight concrete) with various proportions of Portland cement. The research in this paper is separated into two parts, in the first part, the density, water absorption and compressive strength of 7.0 cm x 7.0 cm x 7.0 cm concrete sample was investigated. This study found that the optimal proportion of Portland cement was 15% by weight (this condition showed the highest compressive strength of 3.62 MPa). The physical and mechanical properties of lightweight concrete conformed to the Thai Industrial Standard 2601-2013. In the second step, the thermal properties of the improved lightweight concrete, brick and commercial concrete were compared. It was found that the samples with increasing 15% by weight of Portland cement showed the lowest heat flux that affected to a lower tested room temperature as well.
The Study on Physical and Thermal Properties of Geopolymer Pastes
Authors: Jittabut Pongsak
Published: August 2017

This research was aimed to a present the physical and thermal properties of geopolymer pastes made of fly ash (FA) and bagasse ash (BA) with rice husk ash (RHA) containing at the doses of 0%, 2%, 4%, 6%, 8% and 10% by weight. The sodium hydroxide concentration of 15 molars, sodium silicate per sodium hydroxide by weight ratio of 2.0, the alkaline liquid per binder at the ratio of 0.60 and curing at ambient temperature were used at the to mix all mixtures to gether for 7 and 28 days. The properties analysis of the geopolymer pastes such as compressive strength, bulk density, water absorption, thermal conductivity, thermal diffusivity and thermal capacity were tested. The results were indicated that geopolymer pastes that containing rice husk ash 2% by weight for 28 days of curing gave the maximum compressive strength of 84.42 kg/cm2, low water absorption of 1.16 %, low bulk density of 2,065.71 kg/cm3, lower thermal conductivity of 1.1173 W/m.K, lower thermal diffusion of 6.643 µm2/s and lower thermal capacity of 1.6819 MJ/m3K, respectively. The utilization of waste from agriculture industry via geopolymer pastes for green building materials can be achieved. For this research, physical properties and thermal insulation of geopolymer pastes were siqnificantly improved.
Optimum Partial Replacement of Cement by Nanosilica, Microsilica and Rice Husk Ash for Mass Production of Concrete
Authors: Ouypornprasert Winai , Traitruengtatsana Narong , Kamollertvara Kong
Published: August 2017

The objective of this technical paper was to propose the use of optimum partial replacement of cement by pozzolan of high-silica content i.e. nanosilica, silica fume and rice husk ash. Firstly cement hydration, pozzolanic reactions of pozzolan and stoichiometry were reviewed. Then the optimum fractional replacement of cement by pozzolan based on the complete consumption of calcium hydroxide and the strength activity index (SAI) were formulated and proposed. After that the results of a series of tests of cement mortars were shown to verify the proposed concepts. The applicability for the mass concrete production was demonstrated by prediction of mean values of nonnormal distributions from the corresponding specifications.
Synthesis and Characterization of Cerium- and Lanthanum Containing Bioactive Glass
Authors: Ershad Md , Vyas Vikas Kr , Prasad Sunil , Ali Akher , Pyare Ram
Published: August 2017

Synthesis and characterization of bioglass® of general composition (45-X-Y) SiO2, 24.5 Na2O, 24.5 CaO and 6.0 P2O5 (wt %) was modified by addition of X= (0-1) wt % of CeO2 and Y= (0-1) wt % of La2O3 respectively. These five samples were prepared in alumina crucible via melting route at a temperature of 1400±5 °C with air as a furnace atmosphere. These glass samples were immersed in simulated body fluid (SBF) for different time period and their bioactivity were determined by Fourier transform infrared spectroscopy (FTIR) analysis. Surface morphology was studied by using Scanning electron microscope (SEM). Bioactivity, pH measurement of bioactive glass was carried out and mechanical properties of these glasses increased with increasing concentration of CeO2 and La2O3.
PMMA Demonstrated Higher Elastic Modulus and Nanohardness Compared with Polyamide Denture Base Materials
Authors: Nasution Hubban , Arksornnukit Mansuang
Published: August 2017

The elastic modulus and nanohardness of denture bases may be different based on the type of material. The purpose of this study was to compare the elastic modulus and nanohardness of polyamide and polymethyl methacrylate (PMMA) denture base materials. Three polyamide denture base materials (Valplast, Lucitone FRS, and Thermoplastic Comfort System (TCS)) and one Polymethyl methacrylate (PMMA,Triplex Hot) denture base material (n=10) were evaluated to compare their elastic modulus and nanohardness values using an ultramicroindentation system (UMIS 2000; CSIRO, Lindfield, Australia). The data were statistically analyzed using one-way ANOVA, followed by Tukey HSD and Tamhane’s post hoc tests (α=.05). The elastic modulus and nanohardness of PMMA were significantly higher compared to the polyamide groups (P<.05). All the materials showed significant differences in each of their elastic modulus and nanohardness (P<.05). The values of nanohardness and elastic modulus of each group were as follows: Triplex Hot > Lucitone FRS > Valplast > TCS. The elastic modulus and nanohardness values varied among the polyamide denture base materials. PMMA showed higher elastic modulus and nanohardness than the polyamide. A strong positive correlation existed between elastic modulus and nanohardness of the denture bases tested (R2 = 0.979, P<.05).
Determination of Tannin in Coffee Pulp Using Experimental and Theoritical Approches
Authors: Rakitikul Waleepan
Published: August 2017

Currently, Doi Chaang village is the biggest area producing coffee in Thailand. Throughout seed to cup the pulp must be removed from coffee cherry after harvesting and left as waste. Tannin is one of various composition in coffee pulp which is affected by soil nutrition and pH. In this study, we have characterized the amount of tanin in coffee pulp using UV-Visible spectroscopy and electronic structure calculation. The results showed that coffee pulp consist of 5.68% tannin . It was determined to condense tannin form. Moreover, the pH of soil after treated with modified coffee pulp with water, Ca(OH)2, Na2S2O5, 2% Ca(OH)2, and 2% Na2S2O5 is higher than that with non-modified case. Likewise, DFT calculations predicted the structure of tannin with smaller HOMO-LUMO gap in the condense tannin.
Performance Photocatalytic Degradation of Methomyl onto Composite Graphene Oxide/Bismuth Vanadate (GO/BiVO4) Nanoparticle
Authors: Pookmanee Pusit , Longchin Pimchanok , Phanmalee Jitreephan , Kangwansupamonkon Wiyong , Phanichphant Sukon
Published: August 2017

Graphene oxide (GO) powder was synthesized by modified Hummer’s method. Bismuth vanadate (BiVO4) nanoparticle was synthesized by solvothermal method at 100 and 200°C for 3h. Composite graphene oxide and bismuth vanadate (GO/BiVO4) nanoparticle were synthesized by mixed oxide method in weight ratio of 0.20:1.00. The physical and chemical properties were characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDS) and surface area analyzer (BET). The photocatalytic degradation of methomyl performance was determined by high performance liquid chromatograph (HPLC). Composite GO/BiVO4 nanoparticle at 200°C for 3h was the highest photocatalytic degradation of methomyl.
Adsorption of Reactive Dye (RB 222) in Solution onto Chitosan-Rice Husk Ash Composite Beads Cross-Linked with Glutaraldehyde
Authors: Sananmuang Ratana , Chuachuad Chaiyasith Wipharat , Paroon Kalayaporn
Published: August 2017

The adsorption of reactive dye (RB 222) onto cross-linked chitosan-rice husk ash composite beads was investigated. BET, SEM and FTIR methodologies were used to characterize the properties of the composite beads. The results indicated that the BET surface area values of cross-linked chitosan-rice husk ash composite beads were 4 .740 m2 /g . The effects of various parameters on the adsorption behavior of composite beads including pH (2-12), temperature (20°C, 30°C and 40°C), and initial concentration (10-850 mg/L) were studied. The dye concentrations after adsorption process were measured using a UV/VIS Spectrophotometer at 611 nm. For the effect of pH on reactive dye (RB 222) removal, the highest value of dye removal was obtained at pH 2. The isotherm study was fitted by Freundlich Isotherm. Moreover, thermodynamics of adsorption was also found that the △Go had negative values. It indicates the feasibility of adsorption process at temperature below 40°C.
Preparation, Characterization and Photocatalytic Properties of Rubber-TiO2-rGO Composite Sheets for Dye Decomposition in Wastewater
Authors: Tejangkura Worapol , Sriwong Chaval , Choojun Kittisak
Published: August 2017

In this work, rubber-TiO2-rGO (RT-rGO) composite sheets were successfully prepared by a simple latex mixing-casting method using TiO2 and natural rubber latex with different amounts of rGO loading. The prepared RT-rGO sheet samples were characterized by XRD, FT-IR, Raman, SEM and EDS techniques. The photocatalytic properties of the prepared RT-rGO sheets as catalyst were evaluated using methylene blue (MB) dye solution under UV light irradiation. The result indicated that all the composite sheets loaded with rGO had better photocatalytic activities than the sheet without rGO loading. RT-rGO6.2% sheet showed the highest removal efficiency of 93.3% which has the rate constant (kapp) as 98.2 times higher than the unloaded sheet. Furthermore, the efficiency of the RT-rGO sheet upon the repeated usage was also studied. The result indicated that the sheet could be easily used, recovered and reused many times with no need for the cleaning in between successive uses. Thus, the RT-rGO sheet appears to be an attractive-material for the wastewater treatment or the water purification industry.
Using ZnO Nanorods Coated Porous Ceramic Monolith to Remove Arsenic from Groundwater
Authors: Khwamsawat Kannika , Mahujchariyawong Jukkrit , Danwittayakul Supamas
Published: August 2017

Arsenic contaminants in drinking water pose a threat to human health. In this study, we report the use of nanotechnology to enhance the efficiency of arsenic removal. In here, zinc oxide (ZnO) has been selected for this application due to its environmentally friendly to human being. One-dimensional ZnO nanorods were grown on porous ceramic substrate by hydrothermal technique. The monolith nano-adsorbents were investigated using field emission scanning electron microscope (FESEM, Hitachi, SE-8030), while phase compositions and specific surface area were examined by x-ray diffractometer (XRD, PAnalitical, X’Pert PRO). Experiments of arsenic adsorption were conducted by using 200 ppb arsenic concentration solution with a continuously stirring system. After the adsorption, each water sample was then measured the arsenic content by inductively coupled plasma-optical emission spectroscope (ICP-OES) as compare to the original water sample to calculate the percentage of arsenic removal. We found that morphology of nano-adsorbent on using the growth solution concentration of 20mM of growth solution concentration and 20 hours of growth time showed the highest density of ZnO hexagonal nanorods with about 100 nm in diameter. The optimization studies obtained 30 minute of adsorption time, pH as 7. This nano-adsorbent exhibited about 98% of arsenic removal. For the comparison with commercial adsorbent (As600), ZnO nano-adsorbent has a better efficiency. The strong competitive ion on the arsenic removal was PO43-. Moreover, the real groundwater after treatment doesn’t have any toxic residue. Therefore, ZnO nanorods coated on porous ceramic can be the candidate material for arsenic removal from groundwater.