Search results for: iris scanning
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 512

Search results for: iris scanning

242 Electrochemical Performance of Al-Mn2O3 Based Electrode Materials

Authors: Noor Ul Ain Bhatti, M. Junaid Khan, Javed Ahmad, Murtaza Saleem, Shahid M. Ramay, Saadat A. Siddiqi

Abstract:

Manganese oxide is being recently used as electrode material for rechargeable batteries. In this study, Al incorporated Mn2O3 compositions were synthesized to study the effect of Al doping on electrochemical performance of host material. Structural studies were carried out using X-ray diffraction analysis to confirm the phase stability and explore the lattice parameters, crystallite size, lattice strain, density and cell volume. Morphology and composition were analyzed using field emission scanning electron microscope and energy dispersive X-ray spectroscopy, respectively. Dynamic light scattering analysis was performed to observe the average particle size of the compositions. FTIR measurements exhibit the O-Al-O and O-Mn-O and Al-O bonding and with increasing the concentration of Al, the vibrational peaks of Mn-O become sharper. An enhanced electrochemical performance was observed in compositions with higher Al content.

Keywords: Mn2O3, electrode materials, energy storage and conversion, electrochemical performance.

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241 Green Prossesing of PS/Nanoparticle Fibers and Studying Morphology and Properties

Authors: M. Kheirandish, S. Borhani

Abstract:

In this experiment Polystyrene/Zinc-oxide (PS/ZnO) nanocomposite fibers were produced by electrospinning technique using limonene as a green solvent. First, the morphology of electrospun pure polystyrene (PS) and PS/ZnO nanocomposite fibers investigated by SEM. Results showed the PS fiber diameter decreased by increasing concentration of Zinc Oxide nanoparticles (ZnO NPs). Thermo Gravimetric Analysis (TGA) results showed thermal stability of nanocomposites increased by increasing ZnO NPs in PS electrospun fibers. Considering Differential Scanning Calorimeter (DSC) thermograms for electrospun PS fibers indicated that introduction of ZnO NPs into fibers affects the glass transition temperature (Tg) by reducing it. Also, UV protection properties of nanocomposite fibers were increased by increasing ZnO concentration. Evaluating the effect of metal oxide NPs amount on mechanical properties of electrospun layer showed that tensile strength and elasticity modulus of the electrospun layer of PS increased by addition of ZnO NPs. X-ray diffraction (XRD) pattern of nanopcomposite fibers confirmed the presence of NPs in the samples.

Keywords: Electrospininng, nanoparticle, polystyrene, ZnO.

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240 Mucosal- Submucosal Changes in Rabbit Duodenum during Development

Authors: Elnasharty M. A., Abou-Ghanema I. I., Sayed-Ahmed A., A. Abo Elnour

Abstract:

The sequential morphologic changes of rabbit duodenal mucosa-submucosa were studied from primodial stage to birth in 15 fetuses and during the early days of life in 21 rabbit newborns till maturity using light, scanning and transmission electron microscopy. Fetal rabbit duodenum develops from a simple tube of stratified epithelium to a tube containing villus and intervillus regions of simple columnar epithelium. By day 21 of gestation, the first rudimentary villi were appeared and by day 24 the first true villi were appeared. The Crypts of Lieberkuhn did not appear until birth. By the first day of postnatal life the duodenal glands appeared. The histological maturity of the rabbit small intestine occurred one month after birth. In conclusion, at all stages, the sequential morphologic changes of the rabbit small intestine developed to meet the structural and physiological demands during the fetal stage to be prepared to extra uterine life.

Keywords: Duodenum, mucosa, submucosa, morphogenesis, rabbit.

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239 Conventional Synthesis and Characterization of Zirconium Molybdate, Nd2Zr3(MoO4)9

Authors: G. Çelik Gül, F. Kurtuluş

Abstract:

Rare earths containing complex metal oxides have drawn much attention due to physical, chemical and optical properties which make them feasible in so many areas such as non-linear optical materials and ion exchanger. We have researched a systematic study to obtain rare earth containing zirconium molybdate compound, characterization, investigation of crystal system and calculation of unit cell parameters.  After a successful synthesis of Nd2Zr3(MoO4)9 which is a member of rare earth metal containing complex oxides family, X-ray diffraction (XRD), High Score Plus/Rietveld refinement analysis, and Fourier Transform Infrared Spectroscopy (FTIR) were completed to determine the crystal structure. Morphological properties and elemental composition were determined by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. Thermal properties were observed via Thermogravimetric-differential thermal analysis (TG/DTA).

Keywords: Nd2Zr3(MoO4)9, solid state synthesis, powder x-ray diffraction, zirconium molybdates.

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238 Properties of Bio-Phenol Formaldehyde Composites Filled with Empty Fruit Bunch Fiber

Authors: Sharifah Nabihah Syed Jaafar, Umar Adli Amran, Rasidi Roslan, Chia Chin Hua, Sarani Zakaria

Abstract:

Bio-composites derived from plant fiber and/or bioderived polymer, are likely more ecofriendly and demonstrate competitive performance with petroleum based composites. In this research, the bio phenol-formaldehyde (bio-PF) was used as a matrix and oil palm empty fruit bunch fiber (EFB) as reinforcement. The matrix was synthesized via liquefaction and condensation to enhance the combination of phenol and formaldehyde, during the process. Then, the bio-PF was mixed with different percentage of EFB (5%, 10%, 15% and 20%) and molded at 180oC. The samples that viewed under scanning electron microscopy (SEM) showed an excellent wettability and interaction between EFB and matrix. Samples of 10% EFB gave the optimum properties of impact and hardness meanwhile sample 15% of EFB gave the highest reading of flexural modulus (MOE) and flexural strength (MOR). For thermal stability analysis, it was found that the weight loss and the activation energy (Ea) of the bio-composites samples were decreased as the filler content increased.

Keywords: EFB, liquefaction, phenol formaldehyde, lignin.

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237 Modelling Medieval Vaults: Digital Simulation of the North Transept Vault of St Mary, Nantwich, England

Authors: N. Webb, A. Buchanan

Abstract:

Digital and virtual heritage is often associated with the recreation of lost artefacts and architecture; however, we can also investigate works that were not completed, using digital tools and techniques. Here we explore physical evidence of a fourteenth-century Gothic vault located in the north transept of St Mary’s church in Nantwich, Cheshire, using existing springer stones that are built into the walls as a starting point. Digital surveying tools are used to document the architecture, followed by an analysis process to hypothesise and simulate possible design solutions, had the vault been completed. A number of options, both two-dimensionally and three-dimensionally, are discussed based on comparison with examples of other contemporary vaults, thus adding another specimen to the corpus of vault designs. Dissemination methods such as digital models and 3D prints are also explored as possible resources for demonstrating what the finished vault might have looked like for heritage interpretation and other purposes.

Keywords: Digital simulation, heritage interpretation, medieval vaults, virtual heritage, 3D scanning.

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236 Effects of Allelochemical Gramine on Photosynthetic Pigments of Cyanobacterium Microcystis aeruginosa

Authors: Y. Hong, H. Y. Hu, A. Sakoda, M. Sagehashi

Abstract:

Toxic and bloom-forming cyanobacterium Microcystis aeruginosa was exposed to antialgal allelochemical gramine (0, 0.5, 1, 2, 4, 8 mg·L-1), The effects of gramine on photosynthetic pigments (lipid soluble: chlorophyll a and β-carotene; water soluble: phycocyanin, allophycocyanin, phycoerythrin, and total phycobilins) and absorption spectra were studied in order to identify the most sensitive pigment probe implicating the crucial suppression site on photosynthetic apparatus. The results obtained indicated that all pigment parameters were decreased with gramine concentration increasing and exposure time extending. The above serious bleaching of pigments was also reflected on the scanning results of absorption spectra. Phycoerytherin exhibited the highest sensitivity to gramine added, following by the largest relative decrease. It was concluded that gramine seriously influenced algal photosynthetic activity by destroying photosynthetic pigments and phycoerythrin most sensitive to gramine might be contributed to its placing the outside of phycobilins.

Keywords: Absorption spectra, allelochemical, gramine, Microcystis aeruginosa, photosynthetic pigments.

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235 Influence of Nano-ATH on Electrical Performance of LSR for HVDC Insulation

Authors: Ju-Na Hwang, Yong-Jun Park, Min-Hae Park, Kee-Joe Lim

Abstract:

Many studies have been conducted on DC transmission. Of power apparatus for DC transmission, high voltage direct current (HVDC) cable systems are being evaluated because of the increase in power demand and transmission distance. Therefore, dc insulation characteristics of liquid silicone rubber (LSR), which has various advantages such as short curing time and the ease of maintenance, were investigated to assess its performance as a HVDC insulation material for cable joints. The electrical performance of LSR added to nano-aluminum trihydrate (ATH) were confirmed by measurements of the breakdown strength and electrical conductivity. In addition, field emission scanning electron microscope (FE-SEM) was used as a means of confirmation of nanofiller dispersion state. The LSR nanocomposite was prepared by compounding LSR filled nano-sized ATH filler. The dc insulation properties of LSR added to nano-sized ATH fillers were found to be superior to those of the LSR without a filler. 

Keywords: Liquid silicone rubber, Nanocomposite, Nano-ATH, HVDC insulation, Cable joints.

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234 Microstructure and Electrochemical Properties of LiNi1/3Co1/3Mn1/3-xAlxO2 Cathode Material for Lithium Ion Batteries

Authors: Wei-Bo Hua, Zhuo Zheng, Xiao-Dong Guo, Ben-He Zhong

Abstract:

The layered structure LiNi1/3Co1/3Mn1/3-xAlxO2 (x = 0 ~ 0.04) series cathode materials were synthesized by a carbonate co-precipitation method, followed by a high temperature calcination process. The influence of Al substitution on the microstructure and electrochemical performances of the prepared materials was investigated by X-Ray diffraction (XRD), scanning electron microscopy (SEM), and galvanostatic charge/discharge test. The results show that the LiNi1/3Co1/3Mn1/3-xAlxO2 has a well-ordered hexagonal α-NaFeO2 structure. Although the discharge capacity of Al-doped samples decreases as x increases, LiNi1/3Co1/3Mn1/3-0.02Al0.02O2 exhibits superior capacity retention at high voltage (4.6 V). Therefore, LiNi1/3Co1/3Mn1/3-0.02Al0.02O2 is a promising material for “green” vehicles.

Keywords: Lithium ion battery, carbonate co-precipitation, microstructure, electrochemical properties.

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233 Preparation and Properties of Biopolymer from L-Lactide (LL) and ε-Caprolactone (CL)

Authors: A. Buasri, N. Chaiyut, K. Iamma, K. Kongcharoen, K. Cheunsakulpong

Abstract:

Biopolymers have gained much attention as ecofriendly alternatives to petrochemical-based plastics because they are biodegradable and can be produced from renewable feedstocks. One class of biopolyester with many potential environmentally friendly applications is polylactic acid (PLA) and polycaprolactone (PCL). The PLA/PCL biodegradable copolyesters were synthesized by bulk ring-opening copolymerization of successively added Llactide (LL) and ε-caprolactone (CL) in the presence of toluene, using 1-hexanol as initiator and stannous octoate (Sn(Oct)2) as catalyst. Reaction temperature, reaction time and amount of catalyst were evaluated to obtain optimum reaction conditions. The results showed that the %conversion increased with increases in reaction temperature and reaction time, but after a critical amount of catalyst was reached the %conversion decreased. The yield of PLA/PCL biopolymer achieved 98.02% at the reaction temperature 160 °C, amount of catalyst 0.3 mol% and reaction time of 48 h. In addition, the thermal properties of the product were determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA).

Keywords: Biopolymer, Polylactic Acid (PLA), Polycaprolactone (PCL), L-Lactide (LL), ε-Caprolactone (CL)

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232 Strengthening and Toughening of Dental Porcelain by the Inclusion of an Yttria-Stabilized Zirconia Reinforcing Phase

Authors: Bruno Henriques, Rafaela Santos, Mihaela Buciumeanu, Júlio Matias de Souza, Filipe Silva, Rubens Nascimento, Márcio Fredel

Abstract:

Dental porcelain composites reinforced and toughened by 20 wt.% tetragonal zirconia (3Y-TZP) were processed by hot pressing at 1000°C. Two types of particles were tested: yttriastabilized zirconia (ZrO2–3%Y2O3) agglomerates and pre-sintered yttria-stabilized zirconia (ZrO2–3%Y2O3) particles. The composites as well as the reinforcing particles were analyzed by the means of optical and Scanning Electron Microscopy (SEM), Energy Dispersion Spectroscopy (EDS) and X-Ray Diffraction (XRD). The mechanical properties were obtained by the transverse rupture strength test. Wear tests were also performed on the composites and monolithic porcelain. The best mechanical results were displayed by the porcelain reinforced with the pre-sintered ZrO2–3%Y2O3 agglomerates.

Keywords: Composite, dental restoration, porcelain, strengthening, toughening, wear, zirconia.

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231 5-Aminolevulinic Acid-Loaded Gel, Sponge Collagen to Enhance the Delivery Ability to Skin

Authors: Yi-Ping Fang, Hsien-Ting Cheng

Abstract:

Topical photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is an alternative therapy for treating superficial cancer, especially for skin or oral cancer. ALA, a precursor of the photosensitizer protoporphyrin IX (PpIX), is present as zwitterions and hydrophilic property which make the low permeability through the cell membrane. Collagen is a traditional carrier; its molecular composed various amino acids which bear positive charge and negative charge. In order to utilize the ion-pairs with ALA and collagen, the study employed various pH values adjusting the net charge. The aim of this study was to compare a series collagen form, including solution, gel and sponge to investigate the topical delivery behavior of ALA. The in vivo confocal laser scanning microscopy (CLSM) study demonstrated that PpIX generation ability was different pattern after apply for 6 h. Gel type could generate high PpIX, and archived more deep of skin depth.

Keywords: 5-Aminolevulinic acid (ALA), Collagen, Ion-pairs, Penetration behavior

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230 The Effect of Nylon and Kevlar Stitching on the Mode I Fracture of Carbon/Epoxy Composites

Authors: Nisrin R. Abdelal, Steven L. Donaldson

Abstract:

Composite materials are widely used in aviation industry due to their superior properties; however, they are susceptible to delamination. Through-thickness stitching is one of the techniques to alleviate delamination. Kevlar is one of the most common stitching materials; in contrast, it is expensive and presents stitching fabrication challenges. Therefore, this study compares the performance of Kevlar with an inexpensive and easy-to-use nylon fiber in stitching to alleviate delamination. Three laminates of unidirectional carbon fiber-epoxy composites were manufactured using vacuum assisted resin transfer molding process. One panel was stitched with Kevlar, one with nylon, and one unstitched. Mode I interlaminar fracture tests were carried out on specimens from the three composite laminates, and the results were compared. Fractographic analysis using optical and scanning electron microscope were conducted to reveal the differences between stitching with Kevlar and nylon on the internal microstructure of the composite with respect to the interlaminar fracture toughness values.

Keywords: Carbon, delamination, Kevlar, mode I, nylon, stitching.

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229 Preparation of Nanostructure ZnO-SnO2 Thin Films for Optoelectronic Properties and Post Annealing Influence

Authors: Vipin Kumar Jain, Praveen Kumar, Y.K. Vijay

Abstract:

ZnO-SnO2 i.e. Zinc-Tin-Oxide (ZTO) thin films were deposited on glass substrate with varying concentrations (ZnO:SnO2 - 100:0, 90:10, 70:30 and 50:50 wt.%) at room temperature by flash evaporation technique. These deposited ZTO film were annealed at 450 0C in vacuum. These films were characterized to study the effect of annealing on the structural, electrical, and optical properties. Atomic force microscopy (AFM) and Scanning electron microscopy (SEM) images manifest the surface morphology of these ZTO thin films. The apparent growth of surface features revealed the formation of nanostructure ZTO thin films. The small value of surface roughness (root mean square RRMS) ensures the usefulness in optical coatings. The sheet resistance was also found to be decreased for both types of films with increasing concentration of SnO2. The optical transmittance found to be decreased however blue shift has been observed after annealing.

Keywords: ZTO thin film, AFM, SEM, Optical transmittance, Sheet resistance.

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228 Morphological Study of Trichomes in Indigofera wightii Grah. ex Wigh & Arn., Indigo Dye Species, Traditionally Used by “Thaisongdam” Thailand

Authors: Supanyika Sengsai, Aree Thongpukdee, Chalermchai Kanchanakachen

Abstract:

The study aimed to collect morphological data of secretory structures that contribute to taxonomy of Indigofera. Detail features of trichomes occurrence in vegetative and reproductive organs of Indigofera wightii Grah. ex Wigh & Arn., a species traditionally used as source of indigo to dye “Thaisongdam” clothing were investigated. Examination through light microscopy and scanning electrom microscopy were done. Non secretory, T-shaped trichomes appeared throughout surfaces of stems, leaves, flowers and fruits. Secretory or glandular trichomes occurred in two types; one has big cylindrical head and short peduncle, distributed on adaxial surface of sepals and around the pedicel, whereas another possesses smaller cylindrical head but long peduncle. The latter was found on apical surface of immature pods. No phenolic and lipophilic compounds were detected from these glands.

Keywords: Indigofera, Thailand, Thaisongdam, trichome.

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227 The Effect of Processing Parameters of the Vinyl Ester Matrix Nanocomposites Based On Layered Silicate on the Level of Exfoliation

Authors: A. I. Alateyah, H. N. Dhakal, Z. Y. Zhang

Abstract:

The study of the effect of the processing parameters on the level of intercalation between the layered silicate and polymer of two different methodology took place. X-ray diffraction, Scanning Electron Microscopy, Energy Dispersive X-ray Spectrometry, and Transmission Electron Microscopy were utilized in order to examine the intercalation level of nanocomposites of both methodologies. It was found that drying the clay prior to mixing with the polymer, mixing time and speed, degassing time, and the curing method had major changes to the level of distribution of the nanocomposites structure. In methodology 1, the presence of aggregation layers was observed at only 2.5 wt.% clay loading whereas in methodology 2 the presence of aggregation layers was found at higher clay loading (i.e. 5 wt.%).

Keywords: Vinyl ester, nanocomposites, layered silicate, characterisations, aggregation layers, intercalation, exfoliation.

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226 Adsorption of Reactive Dye Using Entrapped nZVI

Authors: P. Gomathi Priya, M. E. Thenmozhi

Abstract:

Iron nanoparticles were used to cleanup effluents. This paper involves synthesis of iron nanoparticles chemically by sodium borohydride reduction of ammonium ferrous sulfate solution (FAS). Iron oxide nanoparticles have lesser efficiency of adsorption than Zero Valent Iron nanoparticles (nZVI). Glucosamine acts as a stabilizing agent and chelating agent to prevent Iron nanoparticles from oxidation. nZVI particles were characterized using Scanning Electron Microscopy (SEM). Thus, the synthesized nZVI was subjected to entrapment in biopolymer, viz. barium (Ba)-alginate beads. The beads were characterized using SEM. Batch dye degradation studies were conducted using Reactive black Water soluble Nontoxic Natural substances (WNN) dye which is one of the most hazardous dyes used in textile industries. Effect of contact time, effect of pH, initial dye concentration, adsorbent dosage, isotherm and kinetic studies were carried out.

Keywords: Ammonium ferrous sulfate solution, barium (Ba)- alginate beads, reactive black WNN dye, zero valent iron nanoparticles.

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225 pH-Responsiveness Properties of a Biodigradable Hydrogels Based on Carrageenan-g-poly(NaAA-co-NIPAM)

Authors: Mohammad Sadeghi, Behrouz Heidari, Korush Montazeri

Abstract:

A novel thermo-sensitive superabsorbent hydrogel with salt- and pH-responsiveness properties was obtained by grafting of mixtures of acrylic acid (AA) and N-isopropylacrylamide (NIPAM) monomers onto kappa-carrageenan, kC, using ammonium persulfate (APS) as a free radical initiator in the presence of methylene bisacrylamide (MBA) as a crosslinker. Infrared spectroscopy was carried out to confirm the chemical structure of the hydrogel. Moreover, morphology of the samples was examined by scanning electron microscopy (SEM). The effect of MBA concentration and AA/NIPAM weight ratio on the water absorbency capacity has been investigated. The swelling variations of hydrogels were explained according to swelling theory based on the hydrogel chemical structure. The hydrogels exhibited salt-sensitivity and cation exchange properties. The temperature- and pH-reversibility properties of the hydrogels make the intelligent polymers as good candidates for considering as potential carriers for bioactive agents, e.g. drugs.

Keywords: superabsorbent, carrageenan, acrylic acid, Nisopropylacrylamide, hydrogel, swelling

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224 Micromachining with ECDM: Research Potentials and Experimental Investigations

Authors: C.S. Jawalkar, Apurbba Kumar Sharma, Pradeep Kumar

Abstract:

Electro Chemical Discharge Machining (ECDM) is an emerging hybrid machining process used in precision machining of hard and brittle non-conducting materials. The present paper gives a critical review on materials machined by ECDM under the prevailing machining conditions; capability indicators of the process are reported. Some results obtained while performing experiments in micro-channeling on soda lime glass using ECDM are also presented. In these experiments, Tool Wear (TW) and Material Removal (MR) were studied using design of experiments and L–4 orthogonal array. Experimental results showed that the applied voltage was the most influencing parameter in both MR and TW studies. Field emission scanning electron microscopy (FESEM) results obtained on the microchannels confirmed the presence of micro-cracks, primarily responsible for MR. Chemical etching was also seen along the edges. The Energy dispersive spectroscopy (EDS) results were used to detect the elements present in the debris and specimens.

Keywords: ECDM, applied-voltage, FESEM, EDS.

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223 Silver Nanoparticles-Enhanced Luminescence Spectra of Silicon Nanocrystals

Authors: Khamael M. Abualnaja, Lidija Šiller, Benjamin R. Horrocks

Abstract:

Metal-enhanced Luminescence of silicon nanocrystals (SiNCs) was determined using two different particle sizes of silver nanoparticles (AgNPs). SiNCs have been characterized by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). It is found that the SiNCs are crystalline with an average diameter of 65 nm and FCC lattice. AgNPs were synthesized using photochemical reduction of AgNO3 with sodium dodecyl sulphate (SDS). The enhanced luminescence of SiNCs by AgNPs was evaluated by confocal Raman microspectroscopy. Enhancement up to x9 and x3 times were observed for SiNCs that mixed with AgNPs which have an average particle size of 100 nm and 30 nm, respectively. Silver NPs-enhanced luminescence of SiNCs occurs as a result of the coupling between the excitation laser light and the plasmon bands of AgNPs; thus this intense field at AgNPs surface couples strongly to SiNCs.

Keywords: Luminescence, Silicon Nanocrystals, Silver Nanoparticles, Surface Enhanced Raman Spectroscopy (SERS).

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222 Design and Fabrication of an Array Microejector Driven by a Shear-Mode Piezoelectric Actuator

Authors: Chiang-Ho Cheng, Hong-Yih Cheng, An-Shik Yang, Tung-Hsun Hsu

Abstract:

This paper reports a novel actuating design that uses the shear deformation of a piezoelectric actuator to deflect a bulge-diaphragm for driving an array microdroplet ejector. In essence, we employed a circular-shaped actuator poled radial direction with remnant polarization normal to the actuating electric field for inducing the piezoelectric shear effect. The array microdroplet ejector consists of a shear type piezoelectric actuator, a vibration plate, two chamber plates, two channel plates and a nozzle plate. The vibration, chamber and nozzle plate components are fabricated using nickel electroforming technology, whereas the channel plate is fabricated by etching of stainless steel. The diaphragm displacement was measured by the laser two-dimensional scanning vibrometer. The ejected droplets of the microejector were also observed via an optic visualization system.

Keywords: Actuator, nozzle, microejector, piezoelectric.

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221 Morphological and Dynamic Mechanical Analyses of a Local Clay/Plantain Fiber Filled Hybrid Polystyrene Composites

Authors: K. P. Odimayomi, A. G. Adeniyi, S. A. Abdulkareem, F. M. Oladipo Emmanuel, C. A. Adeyanju, M. A Amoloye

Abstract:

The abundant availability of the local clay/plantain fiber coupled with the various renewable and sustainability advantages has led to their choice as co-fillers in the development of a hybrid polystyrene composite. The prime objective of this study is to evaluate the morphological and dynamic mechanical properties using Scanning Electron Microscopy and Dynamic Mechanical Analysis. The hybrid polystyrene composite development was developed via the hand-lay-up method. All processing including the constituent mixing and curing were achieved at room temperature (25 ± 2 ℃).   The mechanical characteristics of the developed composites via Dynamic Mechanical Analysis (DMA) confirm an indirect relationship between time and storage modulus, this pattern becomes more evident at higher frequencies. It is clearly portrayed that the addition of clay and plantain fiber in the polystyrene matrix increases the stiffness of the developed composite.

Keywords: Morphology, DMA, Akerebiata clay, plantain fiber, hybrid polystyrene composites.

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220 Synthesis of Aragonite Superstructure from Steelmaking Slag via Indirect CO2 Mineral Sequestration

Authors: Weijun Bao, Huiquan Li

Abstract:

Using steelmaking slag as a raw material, aragonite superstructure product had been synthesized via an indirect CO2 mineral sequestration rout. It mainly involved two separate steps, in which the element of calcium is first selectively leached from steelmaking slag by a novel leaching media consisting of organic solvent Tributyl phosphate (TBP), acetic acid, and ultra-purity water, followed by enhanced carbonation in a separate step for aragonite superstructure production as well as efficiency recovery of leaching media. Based on the different leaching medium employed in the steelmaking slag leaching process, two typical products were collected from the enhanced carbonation step. The products were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM), respectively. It reveals that the needle-like aragonite crystals self-organized into aragonite superstructure particles including aragonite microspheres as well as dumbbell-like spherical particles, can be obtained from the steelmaking slag with the purity over 99%.

Keywords: Aragonite superstructure, Steelmaking slag, Indirect CO2 mineral sequestration, Selective leaching, Enhanced carbonation.

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219 Structural Characteristics of Batch Processed Agro-Waste Fibres

Authors: E. I. Akpan, S. O. Adeosun, G. I. Lawal, S. A. Balogun, X. D. Chen

Abstract:

The characterisation of agro-wastes fibres for composite applications from Nigeria using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) has been done. Fibres extracted from groundnut shell, coconut husk, rice husk, palm fruit bunch and palm fruit stalk are processed using two novel cellulose fibre production methods developed by the authors. Cellulose apparent crystallinity calculated using the deconvolution of the diffractometer trace shows that the amorphous portion of cellulose was permeable to hydrolysis yielding high crystallinity after treatment. All diffratograms show typical cellulose structure with well-defined 110, 200 and 040 peaks. Palm fruit fibres had the highest 200 crystalline cellulose peaks compared to others and it is an indication of rich cellulose content. Surface examination of the resulting fibres using SEM indicates the presence of regular cellulose network structure with some agglomerated laminated layer of thin leaves of cellulose microfibrils. The surfaces were relatively smooth indicating the removal of hemicellulose, lignin and pectin.

Keywords: X-ray diffraction, SEM, cellulose, deconvolution, crystallinity.

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218 Mechanical and Thermal Properties Characterisation of Vinyl Ester Matrix Nanocomposites Based On Layered Silicate

Authors: A. I. Alateyah, H. N. Dhakal, Z. Y. Zhang

Abstract:

The mechanical properties including flexural and tensile of neat vinyl ester and polymer based on layered silicate nanocomposite materials are discussed. The addition of layered silicate into the polymer matrix increased the tensile and flexural modulus up to 1 wt.% clay loading. The incorporation of more clay resulted in decreasing the mechanical properties which was traced to the existence of aggregation layers. Likewise, up to 1 wt.% clay loading, the thermal behaviour showed significant improvements and at higher clay loading the thermal pattern was reduced. The aggregation layers imparted a negative impact on the overall mechanical and thermal properties. Wide Angle X-ray Diffraction, Scanning Electron Microscopy and Transmission Electron Microscopy were utilised in order to characterise the interlamellar structure of nanocomposites.

Keywords: Vinyl ester, nanocomposites, layered silicate, mechanical properties, thermal analysis.

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217 Threats and Preventive Methods to Avoid Bird Strikes at the Deblin Military Airfield, Poland

Authors: J. Cwiklak, M. Grzegorzewski, M. Adamski

Abstract:

The paper presents results of the project conducted in Poland devoted to study on bird strikes at military airfields. The main aim of this project was to develop methods of aircraft protection against threats from birds. The studies were carried out using two methods. One by transect and the other one by selected sector scanning. During the research, it was recorded, that 104 species of birds in the number about of 36000 were observed. The most frequent ones were starling Sturnus vulgaris (31.0%), jackdaw Corvus monedula (18.3%), rook Corvus frugilegus (15.9 %), lapwing Vanellus vanellus (6.2%). Moreover, it was found, that starlings constituted the most serious threat. It resulted from their relatively high attendance at the runway (about 300 individuals). Possible repellent techniques concerning of the Deblin military airfield were discussed. The analysis of the birds’ concentration depending on the altitude, part of the day, year, part of the airfield constituted a base to work out critical flight phase and appropriate procedures to prevent bird strikes.

Keywords: Airport, bird strikes, flight safety, preventive methods.

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216 Deformation of Metallic Foams with Closed Cell at High Temperatures

Authors: Emrah Ersoy, Yusuf Özçatalbas

Abstract:

The aim of this study is to investigate formability of Al based closed cell metallic foams at high temperature. The foam specimens with rectangular section were produced from AlMg1Si0.6TiH20.8 alloy preform material. Bending and free bending tests based on gravity effect were applied to foam specimens at high temperatures. During the tests, the time-angular deformation relationships with various temperatures were determined. Deformation types formed in cell walls were investigated by means of Scanning Electron Microscopy (SEM) and optical microscopy. Bending deformation about 90° was achieved without any defect at high temperatures. The importance of a critical temperature and deformation rate was emphasized in maintaining the deformation. Significant slip lines on surface of cell walls at tensile zones of bending specimen were observed. At high strain rates, the microcrack formation in boundaries of elongated grains was determined.

Keywords: Al alloy, Closed cell, hot deformation, metallic foam.

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215 Application of UAS in Forest Firefighting for Detecting Ignitions and 3D Fuel Volume Estimation

Authors: Artur Krukowski, Emmanouela Vogiatzaki

Abstract:

The article presents results from the AF3 project “Advanced Forest Fire Fighting” focused on Unmanned Aircraft Systems (UAS)-based 3D surveillance and 3D area mapping using high-resolution photogrammetric methods from multispectral imaging, also taking advantage of the 3D scanning techniques from the SCAN4RECO project. We also present a proprietary embedded sensor system used for the detection of fire ignitions in the forest using near-infrared based scanner with weight and form factors allowing it to be easily deployed on standard commercial micro-UAVs, such as DJI Inspire or Mavic. Results from real-life pilot trials in Greece, Spain, and Israel demonstrated added-value in the use of UAS for precise and reliable detection of forest fires, as well as high-resolution 3D aerial modeling for accurate quantification of human resources and equipment required for firefighting.

Keywords: Forest wildfires, fuel volume estimation, 3D modeling, UAV, surveillance, firefighting, ignition detectors.

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214 BIM Application Research Based on the Main Entrance and Garden Area Project of Shanghai Disneyland

Authors: Ying Yuken, Pengfei Wang, Zhang Qilin, Xiao Ben

Abstract:

Based on the main entrance and garden area (ME&G) project of Shanghai Disneyland, this paper introduces the application of BIM technology in this kind of low-rise comprehensive building with complex facade system, electromechanical system and decoration system. BIM technology is applied to the whole process of design, construction and completion of the whole project. With the construction of BIM application framework of the whole project, the key points of BIM modeling methods of different systems and the integration and coordination of BIM models are elaborated in detail. The specific application methods of BIM technology in similar complex low-rise building projects are sorted out. Finally, the paper summarizes the benefits of BIM technology application, and puts forward some suggestions for BIM management mode and practical application of similar projects in the future.

Keywords: BIM, complex low-rise building, BIM modeling, model integration and coordination, 3D scanning.

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213 Segmenting Ultrasound B-Mode Images Using RiIG Distributions and Stochastic Optimization

Authors: N. Mpofu, M. Sears

Abstract:

In this paper, we propose a novel algorithm for delineating the endocardial wall from a human heart ultrasound scan. We assume that the gray levels in the ultrasound images are independent and identically distributed random variables with different Rician Inverse Gaussian (RiIG) distributions. Both synthetic and real clinical data will be used for testing the algorithm. Algorithm performance will be evaluated using the expert radiologist evaluation of a soft copy of an ultrasound scan during the scanning process and secondly, doctor’s conclusion after going through a printed copy of the same scan. Successful implementation of this algorithm should make it possible to differentiate normal from abnormal soft tissue and help disease identification, what stage the disease is in and how best to treat the patient. We hope that an automated system that uses this algorithm will be useful in public hospitals especially in Third World countries where problems such as shortage of skilled radiologists and shortage of ultrasound machines are common. These public hospitals are usually the first and last stop for most patients in these countries.

Keywords: Endorcardial Wall, Rician Inverse Distributions, Segmentation, Ultrasound Images.

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