bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Characterizations of Y-Doped BaCeO3 Ceramic for Use as Electrolyte in Solid Oxide Fuel Cell
Authors: Somkhuan Wiset , Butnoi Pichitchai , Jaita Pharatree , Lertcumfu Narumon , Rujijanagul Gobwute , Tunkasiri Tawee
Published: April 2019

Fuel cell is an electrochemical cell which converts chemical energy into electricity via electrochemical reaction of hydrogen and oxygen gases. It is also an alternative energy with environmental friendly. Generally, the fuel cell consists of many parts. Electrolyte is an important part for fuel cell because it has high ion conductivity which leads to increase electrical conductivity of the fuel cell. In case solid oxide fuel cell, barium cerate-based ceramics have been much attention due to their good properties for the fuel cell. In this work, the BaCe1-xYxO3-δ(x= 0.20) ceramic was synthesized by a solid state reaction in order to study their mechanical and electrical properties. The ceramic was sintered at high temperature of 1500°C with various soaking times. The crystalline phase structure was investigated by X-ray diffraction (XRD). The surface morphologies was observed by a scanning electron microscope (SEM). The impedance properties was measured by LCR meter. The obtained results suggestes that the ceramic sinter at 1500°C with 15 h dewell time shows the best properties as compared to other ceramics.
Glass Batch Modification to Improve the Weathering Resistance in Soda-Lime Silicate Glass
Authors: Meechoowas Ekarat , Jampeerung Parida , Tapasa Kanit , Pantulap Usanee , Jitwatcharakomol Tepiwan
Published: April 2019

The soda bloom - white stain on the glass surface – is an issue concerned in the glass manufacturing. It is because of high humidity and warm weather especially in the tropical region. The aim of this study was to modify glass batch to increase the weathering resistance for soda-lime glass. The weathering resistance of glass was measured by using the sodium (Na) leach technique according to the ISO 719. In principle, the strength of glass structure decreases with increasing Na content. The reactions start when free Na+ions moving to the glass surface and react with moisture from the surroundings. From this reason, the soda bloom occurs during storage lifetime. Two samples of glasses as described in Table 1 were modified with dolomite (CaMg (CO3)2) or alumina (Al2O3) to reduce the sodium free ion on the glass surface and increase the strength of glass structure Table 1: The glasses compositions All glasses were melted at 1500oC for 3 hours and annealed at 570°C. In glass structure, magnesium (Mg) and aluminium (Al) are network modifiers that can improve the structural strength and the weathering resistance of glass. The weathering resistance is in the inverse relationship with the weight of Na2O in mg per 50 ml of water according to theISO 719. The results showed that the weathering resistance increased with increasing dolomite or alumina contents. The experiments of increasing dolomite from 0 to 18 wt.% in a replacement of calcite showed the result that indicated the weight of Na2O in mg per 50 ml of water decreased from 0.53 to 0.41 mg, and the glass with increasing alumina from 0 to 1 wt.% showed that the weight of Na2O in mg per 50 ml of water decreased from 0.80 to 0.39 mg. According to the weathering chamber test under the cyclic atmospheric conditions of 60% and 80% relative humidity, and the cyclic temperatures of 20°C and 32 °C for 14 days, the glasses with more than 12 wt.% dolomite or more than 1 wt.% alumina did not generate the white stains on the surface. This process can be applied in the glass production. The satisfied result was found in the glass sample with 12 wt.% dolomite and 1 wt.% alumina. The weight of Na2O per 50 ml H2O reduced to 0.43 and 0.41mg, respectively, and the storage time increased from 3 months to 6 months without soda bloom.
Fabrication of Li0.06(K0.5,Na0.5)0.94NbO3 Nanofibers by Electrospinning Technique
Authors: Wongsaenmai Supattra , Soitong Tawat
Published: April 2019

In this work, Li0.06(K0.5,Na0.5)0.94NbO3(KNNL) nanofibers were synthesized by sol–gel process and electrospinning technique. The thermal behaviour ofelectrospun fibers was characterized by thermogravimetric analysis (TG) to obtain the calcination temperature range. The structural phase formation and microstructure were characterized by X-ray diffraction technique (XRD) and scanning electron microscopy (SEM), respectively. The crystal structure was identified by XRD as a single-phase perovskite structure, with orthorhombic symmetry. The microstructure shows that the diameters are in the range of 80–160 nm. The electrospun fibers were calcined from 500°C to 900°C and observed the fiber morphology. With increasing calcination temperature, the fiber diameters decreased until the temperature up to 900 °C the morphology change from cylinder to square or rectangular shape grains.
Characteristic and Preparation of TiO2/PVP Nanofiber Using Electrospinning Technique
Authors: Soitong Tawat , Wongsaenmai Supattra
Published: April 2019

In this work, titanium dioxide (TiO2) ceramic nanofiber was prepared by homemade electrospinning technique. A homogeneous solution of titanium isopropoxide in polyvinyl pyrrolidone (PVP) was prepared. The thermal behavior of the fiber was characterized by differential thermal analyzer (DTA) and thermogravimetric analysis (TGA) to obtain the calcination temperature range. Fourier transform infrared spectroscopy (FTIR) was employed to analyze the chemical structures of the TiO2/PVP composite nanofibers. The structural phase formations were characterized by x-ray diffraction technique (XRD). It has been found that the single phase of anatase and rutile were obtained at the calcinations temperature at 500 and 900 °C, respectively. The microstructure was characterized by a scanning electron microscope technique (SEM). The diameter of titanium oxide nanofibers were in the range of 70 nm to 300 nm and decrease as the calcination temperature increasing. The results indicated the effect of calcination temperature on the crystalline phase and morphology of the nanofiber.
A Case Study of Recycled Poly(Lactic Acid) Contaminated with Petroleum-Based Thermoplastics Used in Packaging Application
Authors: Patanathabutr Pajaera , Soysang Patiphan , Leuang-On Pakjira , Kasetsupsin Piyapon , Hongsriphan Nattakarn
Published: April 2019

This study was designed to evaluate properties of poly(lactic acid) (PLA) under the postulation that recycled PLA (rPLA) was contaminated with commodity thermoplastics during a typical density-based sorting. Change in clarity, mechanical, and thermal properties of the contaminated rPLA specimens were compared. Clarity of rPLA was reduced showing pale brownish tint when passing multiple processing. Contamination with either PP or HIPS just 1 phr caused rPLA to become opaque, which the transmittance percentage was decreased with respect to contamination content. Compared to pure PLA, the moduli of rPLA was reduced 2.6%. The moduli of rPLA was reduced 4.5-8.2% when contaminated with PP of 1-8 phr, and the moduli was reduced 1.4-4.1% when contaminated with HIPS of 1-8 phr. Elongation at break of PP-contaminated rPLA specimens was reduced with slight increase of impact strength. Elongation at break of HIPS-contaminated rPLA specimens was higher with higher HIPS content, and the impact strength was enhanced up to 64%.
Effect of ZrO2 and MgO Addition on Structure, Mechanical and Thermal Properties of Metakaolin-Based Geopolymer Composites
Authors: Wongmaneerung Rewadee
Published: April 2019

This research studies the fabrication and properties of reinforced-geopolymer composites for Green Building. The study comprises of phase formation, microstructure, mechanical and thermal properties. Metakaolin-based geopolymer has been fabricated from calcined kaolin at 750 °C for 6 h. Sodium hydroxide solution with 10 M and sodium silicate solution were used as alkaline activators. The ratio between metakaolin and solution was 1:1.25. Two reinforcements; ZrO2 and MgO at the composition of 0, 1, 3, 5, 7 and 9 wt% were added, then well-mixed together. After casting in acrylic mold, samples were cured at 50 °C for 72 h and then stored in air for 7 and 28 days. Phase formation, microstructure, compressive strength and thermal conductivity were determined by XRD, SEM, universal testing and thermal conductivity measurement, respectively. The results revealed that after stored for 28 days, XRD patterns of geopolymer with and without reinforcements show typical amorphous characteristic. Microstructure observation revealed the dense and heterogenous. The addition both of reinforcements has no effect on the geopolymerization reaction. Compressive strength tends to increase with increasing the amount of MgO content. Moreover, thermal conductivity slightly increased with the amounts of ZrO2 and MgO increase.
Modelling of Mechanical Properties of Pearlitic Rail Steel
Authors: Boonsukachote Patiphan , Kingklang Saranya , Uthaisangsuk Vitoon
Published: April 2019

Railway has become more essential for both mass and goods transportation so that the rails are required to carry higher loads and exhibit longer lifetime. Thus, mechanical properties, especially strength and toughness of rail steel must be continuously increased. In the present work, microstructure, tensile properties and impact toughness of a pearlitic rail steel grade 900A were firstly characterized. It was found that the investigated steel showed high yield and tensile strengths, but moderate elongation. Subsequently, representative volume elements (RVE) model was employed to investigate the effects of bainitic phase on mechanical properties of pearlitic rail steels. The flow stress curves of the individual phases were defined with regard to the chemical composition. As a result, the relationships between predicted yield strengths and tensile strengths in dependence on the phase fraction of bainite were provided. The model can be used to identify the proper microstructure characteristic of rail steel.
Effect of Poly(Vinyl Alcohol) on Thermoelectric Properties of Sodium Cobalt Oxide
Authors: Oopathump Chutima , Boonthuma Direk , Smith Siwaporn Meejoo
Published: April 2019

Organic polymer composites are relatively simple to process and are therefore used in thermoelectric materials. The organic polymers are used as an adhesive agent between thermoelectric material grains. Thermoelectric effects of poly (vinyl alcohol) (PVA) composited with sodium cobalt oxide (NaxCoO2) were studied in this work. PVA is a low cost and an excellent biocompatibility polymer. High electrical conductivity, high Seebeck coefficient and low thermal conductivity are required in thermoelectric materials. As PVA is an insulating material, the PVA in between NaxCoO2 grain boundaries has an effect on the low electrical conductivity of NaxCoO2 composite. This results in a decrease in thermoelectric efficiency. However, PVA has been utilized to increase the Seebeck coefficient and also enhance thermoelectric efficiency. In order to improve the electrical conductivity of NaxCoO2 composite, PVA removal was produced by furnace heating at 500̊ C to eliminate PVA from NaxCoO2/PVA sample. The general thermoelectric parameters including the Seebeck coefficient, electrical conductivity and power factor of NaxCoO2/PVA and PVA removal sample were compared. X-ray diffraction patterns (XRD) and scanning electron microscope (SEM) images were used to identify the phase identification and morphology study, respectively. The results showed that the PVA removal sample had higher electrical conductivity than the NaxCoO2/PVA sample. However, NaxCoO2/PVA sample had higher thermoelectric performance than the PVA removal sample because the NaxCoO2/PVA sample showed higher Seebeck coefficient and power factor.
Hydroxylated Natural Rubber Effect on Crystallinity and Mechanical Properties of PLA
Authors: Triampanichkul Nutthapong , Boochathum Ploenpit
Published: April 2019

This work focuses on the effect of functionality of hydroxylated natural rubber (HNR) and its loading on crystallinity and mechanical properties of polylactic acid (PLA). HNR with hydroxyl groups of 9.09% by mole was prepared from natural rubber latex via epoxidation reaction and then the epoxy rings were cleavaged to produce the hydroxyl groups by using heating at the temperature of 70 °C. HNR4 with the hydroxyl groups of 15.25% by mole was prepared from ONR4 latex with M̅n of 3.94 × 103 g/mol and M̅w of 5.06 × 103 g/mol. PLA was then blended with the obtained HNR or HNR4 with different weight ratios of PLA:HNR = 70:30 and 60:40. It was found that hydroxylated natural rubber increased the crystallinity of molded PLA sheet from 7.54% to 18.20% for molded PLA:HNR = 70:30 sheet, to 25.16% for molded PLA:HNR = 60:40 sheet and to 24.38% for molded PLA:HNR4 = 70:30 sheet. Morphological analyses revealed the appearance of co-continuous phase in the molded PLA:HNR4 = 70:30 clearer than the molded PLA:HNR = 60:40 and molded PLA:HNR = 70:30 sheets. As a result, it clarified that the higher functionality of hydroxyl groups based on lowering the molecular-weight enhanced the compatibility between PLA and HNR. On the other hand, the mechanical properties of PLA:HNR4 = 70:30 were found to be the highest tensile strength (14.46 MPa), elongation at break (13.62%) and modulus (4.10 MPa) though PLA:HNR = 60:40 gave the highest impact strength of 163.98 J/m. This was believed that the hydroxylated natural rubber enhanced the crystallinity and impact strength of PLA through the interface interaction and/or chemical bonds between hydroxyl groups of HNR and carboxyl terminal groups of PLA.
Application of Ultrasonic Inspection for Microstructure Analysis of Stainless Steel Grade 304L
Authors: Sojiphan Kittichai , Wangsupangkul Phongsathon , Chailampangsuksakul Tanapat
Published: April 2019

Ultrasonic inspection is one of the most widely used non-destructive testing methods for inspection of fabricated structures and components. During ultrasonic inspection, mechanical waves in form of ultrasound are transmitted and propagate through volume of parts or components and reflect when the waves meet with the existing interface such as flaws in the welds. In addition to detection of flaws or defects within the structures, ultrasonic inspection is also used for determination of component thickness as well as characterization of microstructure of different materials. As the ultrasound is transmitted through media, the loss of ultrasound amplitude is referred to as acoustic attenuation. This attenuation effects greatly result from heterogeneity, anisotropy, and different grain sizes of crystalline media the ultrasound goes through. In order to develop the ultrasonic backscattering models for polycrystalline materials, experimental results of the correlation between the changes in attenuation coefficient and the actual microstructure of polycrystalline materials are necessary. This research article presents the preliminary results of this correlation study in stainless steel 304L specimens in as-received conditions compared with different annealed and heat-treated conditions. Such correlations of attenuation coefficient, hardness, and grain size will be used as baseline for future additional characterization technique such as electron backscattered diffraction to better understand the attenuation effects for textured polycrystalline materials.
Dynamic Vulcanization of NR/PCL Blends: Effect of Rotor Speed on Morphology, Tensile Properties and Tension Set
Authors: Thongpin Chanchai , Tanprasert Theeraphat
Published: April 2019

This work aimed to study effect of rotor speed during melt mixing of natural rubber/polycaprolactone (NR/PCL) on the morphology which controls mechanical properties of dynamic vulcanizate using Luperox101 as a curing agent in NR component. The rotor speeds at 60 and 80 rpm were compared. The morphology of NR/PCL vulcanizates elucidated from SEM micrograph showed that the vulcanizates exhibited NR paticles dispersed in PCL matrix. In addition, the phase size of dispersed NR should be smaller with increasing rotor speed due to the increased shear force. This large PCL domain induced stronger strain hardening in stress-strain behavior under tension. This behavior is closed to tensile behavior of PCL and appeared at the vulcanizates. In terms of modulus, Young’s modulus was concentrated and reported. The lower degradation of PCL phase during melt mixing in the vulcanizates prepared from melt mixing at rotor speed of 60 rpm was responsible for higher Young‘s modulus than that prepared from rotor speed of 80 rpm. The tension set of NR/PCL vulcanizates prepared with rotor speed of 60 was higher than that with rotor speed of 80 rpm. It was suggested by Nakason et.al. [1] that the tension set of vulcanizates should be lower than 50 % so that they could be applied for thermoplastic vulcanizates. In this system, tension set values of the vulcanizates containing PCL 30-45 wt.% were lower than 50% in both rotor speed conditions.
Structural Modification of Styrene Maleic Anhydride Copolymers for Plant Bioactive Compound Extraction
Authors: Punyamoonwongsa P. , Kakumyan Pattana , Saichana Natsaran , Tighe Brian
Published: April 2019

Ability of poly (styrene-alt-maleic anhydride) (PSMA) to undergo a conformational transition into an amphipathic α-helix coil offers one possible mechanism by which PSMA surface activity can be switched on or off in response to the pH change. This behaviour allows it to be useful in membrane solubilization for extraction technology. Bioactive compounds are recovered from plant tissues for different reasons. One of the most important reasons is due to the increased demand in nutraceuticals market and modern therapeutics. Despite this, aqueous-based extraction of these compounds has been reported to give low extraction yield. A development of new green extraction protocol is still a challenging task for all researchers nowadays. This study demonstrated, for the first time, possible use of PSMA as a lysis agent for plant bioactive compound extraction. To enhance its membrane affinity at physiological pH, the polymer was esterified with methanol. Both PSMA and its derivative (ePSMA) were characterized in terms of their membrane binding affinity through a combined use of both surface characterization and physical techniques. Analysis of the ternary phase diagrams suggested that ePSMA could facilitate stronger hydrophobically-driven interactions with the lipid. This was convinced by the reduced critical PSMA/lipid mass ratio from 7:1 (PSMA) to 1:1 (ePSMA), as observed in the ternary phase diagrams. Last but not the least, the crude extracts of Coffea robusta leaves obtained from ePSMA-based extraction showed a total phenolic content of 20.32±0.75 mg/g sample, significantly higher than that from the PSMA- (14.24±1.27 mg/g sample) and aqueous-based (16.33±1.03 mg/g sample) extractions. A structural manipulation of PSMA is thus a key to tailor its membrane solubilization and so, the extraction efficacy of bioactive compounds from plant cells.
Use of Water Glass from Rice Husk and Bagasse Ashes in the Preparation of Fly Ash Based Geopolymer
Authors: Gomonsirisuk Khemmakorn , Thavorniti Parjaree
Published: April 2019

The aim of this work is to study the feasibility of preparation of fly ash based geopolymer using sodium water glass from agricultural waste as alternative activators. Rice husk ash and bagasse ash were used as raw materials for producing sodium water glass solution. The sodium water glass were produced by mixing rice husk ash and bagasse ash with NaOH in ball mill and boiling. The prepared sodium water glass were analyzed and used in geopolymer preparation process. The geopolymer paste were prepared by adding the obtained water glass and NaOH with fly ash. After cured at ambient temperature for 7 days, mechanical properties were investigated. Bonding and phases of the geopolymer were also characterized. The geopolymer from rice husk ash presented highest compressive strength about 23 MPa while the greatest for bagasse ash was about 16 MPa.
Activated Carbon Loaded Lignocellulosic Fibers by Pulp Refining Process for Dye and Metal Ion Absorbing Paper
Authors: Witayakran Suteera , Somboon Phichit , Kongcrup Jatuporn , Sampoompuang Chaiyaporn , Lobyam Keowpetch
Published: April 2019

This work developed activated carbon loaded lignocellulosic fibers (kraft pulp) by pulp refining process and used them to form activated carbon paper (AC-paper). AC-paper was used for the removal of dye and heavy metal ions from aqueous solutions. In pulp refining process, kraft pulp was mixed with activated carbon using high consistency refiner with the addition of cationic starch as a binder. The effects of cationic starch and activated carbon concentration on AC-paper properties were investigated. Activated carbon amount of 0, 10, 20, 30, 40 and 50%, and cationic starch amount of 0, 0.25 and 0.50% (% by oven dried weight pulp) were examined. The AC-paper was prepared at basis weight of 60±5 g/m2. Paper mechanical properties, including density, tensile index, burst index, ring crush index, and tear index, were tested according to ISO 5270. The results show that all paper strength properties declined when the amount of activated carbon was increased. Especially, when the activated carbon content above 30%, paper strength was greatly reduced. The improvement of paper strength was observed when with the cationic starch was added. However, the increased of cationic starch amount from 0.25 to 0.50% showed no significantly difference in paper strength. Paper adsorption of dye (methyl orange, (MO)) and heavy metal ions (zinc and iron) were also studied. The AC-paper prepared from fiber with 50% activated carbon and 0.50% cationic starch provided highest adsorption values of both dye and metal ions from aqueous solutions. In this work, the use of 30% activated carbon and 0.50% cationic starch in pulp refining process was chosen as a suitable condition for the preparation of activated carbon loaded fiber because the activated carbon content above 30% could disrupt paper strength. The fiber obtained from this suitable condition gave the paper with adsorption values of 0.62, 16.38 and 16.72 mg/g for MO, Zn2+, and Fe2+, respectively. The developed activated carbon loaded lignocellulosic fibers could be potentially used for various specialty paper products, such as absorbent paper, filter paper and active packaging, in the future.
Association between Extracellular Matrix Accumulation and Oxidative Stress-Induced Apoptosis in Chondrocytes Cultured on 3D-Porous Scaffolds in Static versus Dynamic Cultures
Authors: Lertwimol Tareerat , Sonthithai Pacharapan , Kosorn Wasana , Wongcumchang Marut , Janvikul Wanida
Published: April 2019

The aim of this study was to investigate the relation between the amount of glycosaminoglycans (GAGs) secreted and the level of apoptosis induced by hydrogen peroxide (H2O2) in porcine chondrocytes cultured on two different biodegradable PCL/PHBV scaffolds: one had primary pores solely, while the other possessed both primary and secondary pores, namely PCL/PHBV/0%NaCl and PCL/PHBV/50%NaCl scaffolds, respectively. The scaffolds with an average primary pore size of 200 μm were primarily fabricated by a fused deposition modeling (FDM) machine, and secondary pores on the material surface were then generated after NaCl leaching in a sodium hydroxide solution. The investigation was performed comparatively under static and dynamic environments. In static culture study, more pronounced GAG accumulation was found on the PCL/PHBV/50%NaCl scaffold, suggesting that the secondary pores could promote the chondrogenic function of chondrocytes, and the primary pores could further accommodate the cells to grow and function more productively. Meanwhile, the significant reductions in the levels of apoptosis of chondrocytes, studied in a H2O2-dose dependent manner (0-2 mM), were observed with a use of a flow cytometer when the chondrocytes were cultured on the PCL/PHBV/50%NaCl scaffold in which more GAG content was found. In dynamic culture study, although the total GAG content detected on the PCL/PHBV/50%NaCl scaffold was still significantly higher than that measured on the PCL/PHBV/0%NaCl scaffold, these GAG accumulations were tremendously greater than those found in the static culture. As a consequence, far less oxidative stress-induced apoptotic death was observed in the cells cultured under the dynamic culture. Moreover, cells seemed to be well protected from apoptosis, in the presence of considerable amounts of GAGs; similar degrees of apoptosis (~25%) were observed on the cells cultured on each scaffold at all H2O2 concentrations studied. The obtained results had demonstrated that the degree of chondrocyte apoptosis was somehow related to the level of GAG accumulation.
Effect of Heat Treatment on Mechanical and Setting Properties of TTCP-Based Calcium Phosphate Cement
Authors: Pooput Kannaporn , Sedchaicharn Korkiat , Phuchamnong Anek , Petcharoen Woranan
Published: April 2019

The objective of this study was to investigate the effect of heat treatment on setting reaction and mechanical properties of tetracalcium phosphate (TTCP) and dicalcium phosphase (DCP)-based calcium phosphate cements. CPC pastes were prepared at room temperature and heated at different temperatures (from 37 to 60°C) for 10 min. Then, the preheated CPC pastes were rapidly cooled down to room temperature before further heated at 37°C until they set. Three different CPC formulations prepared from different particle sizes of TTCPs were used for the investigation. From the study, it was found that preheating could accelerate setting reaction for all CPCs according to increasing speed of hydroxyapatite (HA) conversion. The higher the preheating temperature, the faster the cements could set. However, at preheating temperature higher than 60°C longer cement setting times were observed. It may be that at high temperature some liquid content in the CPC paste evaporated, resulting in slow setting reaction rate. Compressive strengths of the cements after immersion in simulated body fluid (SBF) for 7 days increased as a result of an increase of HA conversion.
A Comparative Study of Granular Agglomeration between 3D Printed Hydroxyapatite and Commercial Bone Graft Granules
Authors: Thammarakcharoen Faungchat , Yampakdee Ariya , Buranawat Bovornwut , Suwanprateeb Jintamai
Published: April 2019

Granule characteristics and the agglomeration ability of 3D printed hydroxyapatite granules (3DP HA) when contacting water were compared to those of commercial bone graft granules based on hydroxyapatite/β-tricalcium phosphate/collagen mixture (Sunmax). Microstructure, phase composition, water absorption and granular agglomeration of the granules were characterized. SEM showed that the granule sizes of Sunmax were in the range of 0.8-1.5 mm whereas that of 3DP HA was relatively more uniform at about 1 mm. 3DP HA granules comprised the weaving of numerous minute crystals containing large pores and having high porosity while Sunmax granules were crushed granules and having low porosity. XRD analysis confirmed that Sunmax granules were biphasic hydroxyapatite and β-tricalcium phosphate while 3DP HA granules were monophasic hydroxyapatite. Sunmax granules exhibited greater agglomeration volume than that of 3DP HA granules. However, the water absorption of 3DP HA granules was greater than that of Sunmax granules. The greater agglomeration ability of Sunmax granules was likely due to the collagen constituent of the granules which could act as adhesive to bind granules together in addition to water capillary action. In contrast, 3DP HA granules formed the agglomeration by the water film due to the capillary action only so the efficiency was lower although the water absorption was greater.
Physical and Electrical Property of TiO2 Nanotube Arrays for Supercapacitors
Authors: Chumphongphan Somwan
Published: April 2019

TiO2 nanotube arrays (TiO2 NTAs) were prepared by anodization method. The as-prepared TiO2 NTAs were annealed at 450 °C for 3 h transforming amorphous TiO2 to anatase TiO2. The inner diameter and tube length of synthesized TiO2 NTAs are approximately 100 nm and 1.0 mm, respectively. Electric double-layer capacitor (EDLC) was fabricated using TiO2 NTAs as electrodes with 6 M KOH electrolyte. The internal resistance of the EDLC is relatively low (3.8 – 6.5 Ω) depending on the operating temperature. This work confirmed experimentally the use of TiO2 NTAs as EDLC electrodes.
Licenza di uccidere. Per un’analisi critica delle tesi di Jeff McMahan / Licence to kill. For a critical analysis of Jeff McMahan’s theses
Authors: Voce Valentina
Published: April 2019

Questo articolo prende in esame la riformulazione del concetto di persona, proposta dal filosofo Jeff McMahan in The Ethics of Killing, come embodied mind. La proposta teorica di McMahan ha una chiara valenza pratica perché, in accordo con una prospettiva funzionalista, identifica la persona con l’acquisizione delle sue capacità cognitive, tracciando una linea discriminatoria tra esseri umani: alcuni non sarebbero persone e pertanto non potrebbero condividere gli stessi diritti che “noi” persone abbiamo. McMahan sviluppa, sulla base di questa impostazione, una gerarchia etica che rende legittima l’uccisione di tutti quegli esseri umani che, a suo avviso, non si possono considerare persone come ad esempio embrioni, feti e individui in stato vegetativo. Il saggio, che rende conto di alcune interessanti annotazioni critiche svolte dalla filosofa Eva Kittay alla proposta di McMahan, si propone di valutare la consistenza teorica di questa teoria e di porla in riferimento alla questione etica e sociale connessa con la tutela dei diritti delle persone con disabilità cognitiva grave. Sulla base delle considerazioni svolte, si è giunti alla conclusione che le teorie di McMahan, e le conseguenze che ne derivano per l’etica pratica, vadano respinte in quanto la separazione tra la nozione di persona e quella di essere umano non risulta adeguatamente giustificata, essendo fondata su una mistificazione dell’uomo privato della sua fondamentale dimensione corporea. ---------- This article takes into account the redefinition of the concept of personhood as embodied mind, proposed by philosopher Jeff McMahan in his book The Ethics of Killing. McMahan’s theoretical proposal has clear practical implications because, according with a functionalist perspective, he identifies personhood with the acquisition of sophisticated cognitive abilities, drawing a discriminatory line among human beings: some are non-persons and therefore they do not share the same rights we persons have. Based on this approach, McMahan develops an ethical hierarchy that makes legitimate the killing of all human beings who, according to his theories, can not be considered as persons, such as embryos, fetuses, and individuals in a vegetative state. The essay, which considers some interesting critical annotations made by philosopher Eva Kittay to McMahan’s proposal, intends to evaluate the theoretical consistency of his theory and to connect it to the ethical and social matter of recognizing and protecting the rights of people with severe cognitive disability. On the basis of our considerations, we concluded that McMahan’s theories, and their consequences for practical ethics, should be rejected because the disjunction between the notion of personhood and that of human being is not properly demonstrated, being based on a mystification of mankind deprived of its fundamental bodily dimension.
Prevalence of gastrointestinal helminths and parasites in smallholder pigs reared in the central Free State Province
Authors: Nwafor Ifeoma C. , Roberts Hester , Fourie Pieter
Published: April 2019

Pigs are kept by farmers as a source of livelihood and food. Unfortunately, helminthiasis and other internal parasites are major setbacks to profitable pig production in Africa. There is a lack of information on the prevalence and intensity of gastrointestinal helminths and parasites plaguing resource-poor pig farmers in the Free State. Knowledge of these endemic parasites can be used as baseline data to help design future intervention plans. The aim of this study was to identify and quantify the types of gastrointestinal helminths and parasites prevalent in smallholder pigs reared in the central Free State Province. Faecal samples were randomly collected from 77 pigs and parasitologically analysed. Quantification was done using the McMaster counting technique. Farming system, age, gender and health status were the risk factors considered. The study was conducted between January and March 2016. Overall, results showed that 61 samples (79.2%) tested positive for one or more gastrointestinal parasites, which were observed as single or mixed infections. Amongst the positive samples, 44.5% were infected with Ascaris suum, 50.6% with Trichuris suis, 26.0% and 72.7% were infected with Oesophagostomum dentatum and coccidia, respectively. There were significant differences (p < 0.05) between the rate of infection in the intensive and semi-intensive systems and between the dewormed and non-dewormed pigs. Piglets and female pigs recorded a higher prevalence in their categories. Pigs excreted mostly low (eggs per gram [EPG] ≤ 100) to moderate (EPG > 100 < 500) levels of helminth eggs. It is concluded that different species of gastrointestinal parasites are present in most pigs reared by smallholder farmers in this study area.
A comprehensive characterization of ice nucleation by three different types of cellulose particles immersed in water
Authors: Hiranuma Naruki , Adachi Kouji , Bell David M. , Belosi Franco , Beydoun Hassan , Bhaduri Bhaskar , Bingemer Heinz , Budke Carsten , Clemen Hans-Christian , Conen Franz , Cory Kimberly M. , Curtius Joachim , DeMott Paul J. , Eppers Oliver , Grawe Sarah , Hartmann Susan , Hoffmann Nadine , Höhler Kristina , Jantsch Evelyn , Kiselev Alexei , Koop Thomas , Kulkarni Gourihar , Mayer Amelie , Murakami Masataka , Murray Benjamin J. , Nicosia Alessia , Petters Markus D. , Piazza Matteo , Polen Michael , Reicher Naama , Rudich Yinon , Saito Atsushi , Santachiara Gianni , Schiebel Thea , Schill Gregg P. , Schneider Johannes , Segev Lior , Stopelli Emiliano , Sullivan Ryan C. , Suski Kaitlyn , Szakáll Miklós , Tajiri Takuya , Taylor Hans , Tobo Yutaka , Ullrich Romy , Weber Daniel , Wex Heike , Whale Thomas F. , Whiteside Craig L. , Yamashita Katsuya , Zelenyuk Alla , Möhler Ottmar
Published: April 2019

Abstract. We present the laboratory results of immersion freezing efficiencies of
cellulose particles at supercooled temperature (T) conditions. Three types of
chemically homogeneous cellulose samples are used as surrogates that
represent supermicron and submicron ice-nucleating plant structural
polymers. These samples include microcrystalline cellulose (MCC), fibrous
cellulose (FC) and nanocrystalline cellulose (NCC). Our immersion freezing
dataset includes data from various ice nucleation measurement techniques
available at 17 different institutions, including nine dry dispersion
and 11 aqueous suspension techniques. With a total of 20 methods, we
performed systematic accuracy and precision analysis of measurements from
all 20 measurement techniques by evaluating T-binned (1 ∘C)
data over a wide T range (−36 ∘C <T<-4 ∘C). Specifically, we intercompared the geometric surface
area-based ice nucleation active surface site (INAS) density data derived from
our measurements as a function of T, ns,geo(T). Additionally, we also
compared the ns,geo(T) values and the freezing spectral slope parameter
(Δlog(ns,geo)/ΔT) from our measurements to previous
literature results. Results show all three cellulose materials are
reasonably ice active. The freezing efficiencies of NCC samples agree
reasonably well, whereas the diversity for the other two samples spans
≈ 10 ∘C. Despite given uncertainties within each
instrument technique, the overall trend of the ns,geo(T) spectrum traced
by the T-binned average of measurements suggests that predominantly
supermicron-sized cellulose particles (MCC and FC) generally act as more
efficient ice-nucleating particles (INPs) than NCC with about 1 order of
magnitude higher ns,geo(T).
Aerosol Vertical Mass Flux Measurements During Heavy Aerosol Pollution Episodes at a Rural Site and an Urban Site in the Beijing Area of the North China Plain
Authors: Yuan Renmin , Zhang Xiaoye , Liu Hao , Gui Yu , Shao Bohao , Tao Xiaoping , Wang Yaqiang , Zhong Junting , Li Yubin , Gao Zhiqiu
Published: April 2019

Abstract. Due to excessive anthropogenic emissions, heavy aerosol pollution episodes (HPEs) often occur during winter in the Beijing-Tianjin-Hebei (BTH) area of the North China Plain. Extensive observational studies have been carried out to understand the causes of HPEs; however, few measurements of aerosol vertical fluxes exist, despite them being the key to understanding vertical aerosol mixing, specifically during weak turbulence stages in HPEs. In the winter of 2016 and the spring of 2017, based on the light propagation theory and surface-layer similarity theory, aerosol vertical mass fluxes were measured by combining large aperture scintillometer (LAS) observations, surface PM2.5 and PM10 mass concentrations, and meteorological observations, including temperature, relative humidity (RH), and visibility, at a rural site in Gucheng (GC), Hebei Province, and an urban site at the Chinese Academy of Meteorological Sciences (CAMS) in Beijing located 100 km to the northeast. The near-ground aerosol mass flux was generally lower in winter than in spring and weaker in rural GC than in urban Beijing. This finding provides direct observational evidence from the perspective of vertical aerosol fluxes for a weakened turbulence intensity in winter and in polluted areas such as GC. The HPEs included a transport stage (TS), an accumulative stage (AS), and a removal stage (RS). During the HPEs from January 25, 2017 to January 31, 2017, in Beijing, the mean mass flux decreased by 51 % from 0.0049 mg m−2 s−1 in RSs to 0.0024 mg m−2 s−1 in the TSs. During the ASs, the mean mass flux decreased further to 0.00087 mg m−2 s−1, accounting for approximately 1/3 of the flux in the TSs. A similar reduction from the TSs to ASs was observed in the HPE from December 16, 2016 to December 22, 2016 in GC. The weakened mass flux indicates that the already weak turbulence would be further weakened by aerosol pollution to a certain extent, which would further facilitate aerosol accumulation.
Distribution and degradation of terrestrial organic matter in the sediments of peat-draining rivers, Sarawak, Malaysian Borneo
Authors: Wu Ying , Zhu Kun , Zhang Jing , Müller Moritz , Jiang Shan , Mujahid Aazani , Muhamad Mohd Fakharuddin , Sia Edwin Sien Aun
Published: April 2019

Abstract. Tropical peatlands are one of the largest pools of terrestrial organic carbon (OCterr); however, our understanding of the dynamics of OCterr in peat-draining rivers remains limited, especially in Southeast Asia. This study used bulk parameters and lignin phenols concentrations to investigate the characteristics of OCterr in a tropical peat-draining river system (the main channel of the Rajang and three smaller rivers) in the western part of Sarawak, Malaysian Borneo. The depleted δ13C levels and lignin composition of the organic matter indicates that the most important plant source of the organic matter in these rivers is woody angiosperm C3 plants, especially in the three small rivers sampled. The diagenetic indicator ratio (i.e., the ratio of acid to aldehyde of vanillyl phenols (Ad / Al)v) increased with decreasing mean grain size of sediment from the small rivers. The selective sorption of acid relative to aldehyde might explain the variations in the (Ad / Al)v ratio. The (Ad / Al)v ratio appears to be related to the C / N ratio (the ratio of total organic carbon to total nitrogen) in the Rajang and small rivers, where slower degradation of OCterr and a higher total nitrogen percentage (TN%) were observed, compared to other river systems. Most of the OCterr discharged from the Rajang and small river systems was material derived from woody angiosperm plants with limited diagenetic alteration before deposition, and so could potentially provide significant carbon to the atmosphere after degradation.
Development of a real-time on-road emission (ROE v1.0)model for street-scale air quality modeling based on dynamic traffic big data
Authors: Wu Luolin , Chang Ming , Wang Xuemei , Hang Jian , Zhang Jinpu
Published: April 2019

Abstract. Rapid urbanization in China has led to heavy traffic flows in street networks within cities, especially in eastern China, the economically developed region. This has increased the risk of exposure to vehicle-related pollutants. To evaluate the impact of vehicle emissions and provide an on-road emission inventory with higher spatial–temporal resolution for street-network air quality models, in this study, we developed the Real-time On-road Emission (ROE v1.0) model to calculate street-scale on-road hot emissions by using real-time big data for traffic provided by the Gaode map navigation application. This Python-based model obtains street-scale traffic data from the map application programming interface (API), which are open-access and updated every minute for each road segment. The results of application of the model to Guangzhou, one of the three major cities in China, showed on-road vehicle emissions of carbon monoxide (CO), nitrogen oxide (NOx), hydrocarbons (HC), PM10, and PM2.5 to be 35.22 × 104 Mg/a, 12.05 × 104 Mg/a, 4.10 × 104 Mg/a, 0.49 × 104 Mg/a, and 0.55 × 104 Mg/a, respectively. The spatial distribution reveals that the emission hotspots are located in some highway-intensive area and suburban town centers. Emission contributions show that the dominant contributors are light-duty vehicles (LDVs) and heavy-duty vehicles in urban areas and LDVs and heavy-duty trucks in suburban areas, indicating that the traffic control policies regarding duty trucks in urban areas are effective. In this study, the Model of Urban Network of Intersecting Canyons and Highways (MUNICH) was applied to investigate the impact of traffic volume change on street-scale photochemistry in the urban area by using the on-road emission results from the ROE model. The modeling results indicate that the daytime NOx concentrations on national holidays are 26.5 % and 9.1 % lower than those on normal weekdays and normal weekends, respectively. Conversely, the national holiday O3 concentrations exceed normal weekday and normal weekend amounts by 13.9 % and 10.6 %, respectively, owing to changes in the ratio of emission of VOCs and NOx. Thus, not only the on-road emission, but other emissions should be controlled in order to improve the air quality in Guangzhou. More significantly, the newly developed ROE model may provide promising and effective methodologies for analyzing real-time street-level traffic emissions and high-resolution air quality assessment for more typical cities or urban districts.
Mapping the susceptibility of syn-eruptive rain-triggered lahars at Vulcano island (Italy) combining field characterization and numerical modelling
Authors: Baumann Valérie , Bonadonna Costanza , Cuomo Sabatino , Moscariello Mariagiovanna , Biasse Sebastien , Pistolesi Marco , Gattuso Alessandro
Published: April 2019

Abstract. Lahars are a widespread phenomenon on Vulcano island (Italy), where many loose pyroclastic deposits provide a significant source of sediments. In this study we have estimated the volumes of tephra-fallout deposit that could be remobilized by rainfall-triggered lahars in association with two eruptive scenarios that have characterized the activity of La Fossa cone: a long-lasting Vulcanian cycle and a subplinian eruption. The spatial distribution and volume of tephra-fallout deposits that could potentially trigger lahars were analysed based on a combination of tephra-fallout probabilistic modelling (with TEPHRA2), slope stability modelling (with TRIGRS), field observations and geotechnical tests. Field characterization includes tephra-fallout primary deposits in the lahar initiation zones and lahar deposits both on the volcanic cone and in the ring plain. Model input data (hydraulic conductivity, friction angle, cohesion, total unit weight of the soil, saturated and residual water content) were obtained from both geotechnical tests and field measurements. In particular, hydraulic conductivity plays an important role on the stability of tephra-fallout deposits. Our parametric analysis has shown that the tephra-fallout critical thickness required to trigger a lahar for the considered rainfall event is between 20–25 cm for the Vulcanian scenario, and between 10–65 cm or
CARACTERIZACIÓN DE HIPERTRIGLICERIDEMIA Y ANTROPOMETRÍA EN PACIENTES ADULTOS EN UNA COMUNIDAD RURAL
Authors: Khatib Lobo Mharian Hassan , Banegas Erazo Rocío Mitchell , Domínguez Euceda Celina Raquel , Pineda Pineda. Guillermo
Published: April 2019

El informe sobre las enfermedades no transmisibles de la Organización Mundial de la Salud (OMS) del 2010 reporta que 80% de las defunciones se deben a enfermedades no transmisibles, y dentro de estas están las enfermedades metabólicas que afectan más a poblaciones de ingresos medios y bajos, diferente a lo que se creía anteriormente, lo cual podría reducirse, si la población evidencia que sus hábitos influyen en su salud. Objetivo: Caracterizar los factores de riesgo asociados a niveles de hiper trigliceridemia en pacientes de 28-40 años que asisten al centro de salud del municipio de Ceguaca, Santa Bárbara, Honduras de septiembre del 2016 a febrero del 2017. Pa- cientes y métodos: Estudio cuantitativo, descriptivo, no experimental, trasversal. Muestra no probabilística por conveniencia de 50 pacientes que cumplían con los crite- rios de inclusión, uno de los criterios fue firmar el consentimiento informado. La tabulación de datos se realizó en SPSS 23, para los gráficos se utilizó el Software Microsoft Excel 2016. Se realizaron medidas de frecuencia y porcentaje. Resultado: La mayoría eran mujeres con 84% (42), y varo- nes 16% (8), edades: 37-40 años 40% (20), 28-32 años 34% (17) y de 33-36 años 26% (13). Nivel de triglicéridos: hombres>150 mg/dl 100% (8), mujeres:> 150 mg/dl 64.3% (27), indice de masa corporal (IMC) entre 30-39.9: 50% (25), perímetro abdominal: en hombres> 102 cm 50% (4), mujeres> 88 cm 86% (36), actividad física: 68% tenían un estilo de vida sedentario y también un 68% presentan antecedentes familiares de dislipidemias. Conclusión: La mayoría de adultos jóvenes presentó hipertrigliceridemia; como factores determinantes la calidad de la dieta, la falta de actividad física y el factor hereditario.
The Influence of Impulsive Personality Traits and Store Environment on Impulse Buying of Consumer in Karachi
Authors: Hussain Sana , Siddiqui Danish Ahmed
Published: April 2019

This study was aimed to understand and assess the role of store environment, impulsive buying personality traits, impulsive buying tendency, and urge to buy on impulsive buying. Data was collected from 250 respondents and analyzed using Structural Equation Modeling technique, findings suggested that impulse buying was positively associated with impulse buying tendency, impulsively personality trait and urge to buy. The most important finding of the study is the insignificant effect of store environment on consumers that are instinctive buyers. The study also suggests that impulsive traits of the consumer directly lead to impulse buying. It actually don’t need some drive such as store environment that would stimulate their impulse buying tendency. However, this study didn’t find any effect of demographic variables (gender and income) on impulse buying tendency. The overall store environment has insignificant effect on consumer impulse purchase but different attributes such as cleanliness and arrangement of product has relative impact on impulse buying that’s why the retailers should focus on store environment elements such as crowd, sales employee, entertainment, lighting, aroma and display etc. to stimulate impulse buying. This study confirmed the role of personality in encouraging impulse buying at retail outlets. Marketers should identify ways to reach out open ended and extrovert people to target their promotional offers.