Search results for: elastic solid
1582 Nanoindentation and Physical Properties of Polyvinyl Chloride/Styrene Co-Maleic Anhydride Blend Reinforced by Organo-Bentonite
Authors: D. E. Abulyazied, S. M. Mokhtar, A. M. Motawie
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Polymer blends represent an important class of materials in engineering applications. The incorporation of clay nanofiller may provide new opportunities for this type of materials to enhance their applications. This article reports on the effects of clay on the structure and properties of polymer blends nanocomposites, based on Polyvinyl chloride PVC and styrene co-maleic anhydride SMA blend. Modification of the Egyptian Bentonite EB was carried out using organo-modifier namely; octadecylamine ODA. Before the modification, the cation exchange capacity CEC of the EB was measured. The octadecylamine bentonite ODA-B was characterized using Fourier transform infrared Spectroscopy FTIR, X-Ray Diffraction XRD, and Transition Electron Microscope TEM. A blend of Polyvinyl chloride PVC and styrene co-maleic anhydride SMA (50:50) was prepared in Tetra Hydro Furan (THF). Then nanocomposites of PVC/SMA/ODA-B were prepared by solution intercalation polymerization from 0.50% up to 5% by weight of ODA-B. The nanocomposites are characterized by XRD, TEM. Thermal, nanoindentation, swelling and electrical properties of the nanocomposites were measured. The morphology of the nanocomposites showed that ODA-B achieved good dispersion in the PVC/SMA matrix. Incorporation of 0.5 %, 1%, 3% and 5% by weight nanoclay into the PVC/SMA blends results in an improvement in nanohardness of 16%, 76%, 92%, and 68% respectively. The elastic modulus increased from 4.59 GPa for unreinforced PVC/SMA blend to 6.30 GPa (37% increase) with the introduction of 3% by weight nanoclay. The cross-link density of the nanocomposites increases with increasing the content of ODA-B.Keywords: PVC, SMA, nanocomposites, nanoindentation, organo-bentonite
Procedia PDF Downloads 3711581 Investigate the Effects of Geometrical Structure and Layer Orientation on Strength of 3D-FDM Rapid Prototyped Samples
Authors: Ahmed A.D. Sarhan, Chong Feng Duan, Mum Wai Yip, M. Sayuti
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Rapid Prototyping (RP) technologies enable physical parts to be produced from various materials without depending on the conventional tooling. Fused Deposition Modeling (FDM) is one of the famous RP processes used at present. Tensile strength and compressive strength resistance will be identified for different sample structures and different layer orientations of ABS rapid prototype solid models. The samples will be fabricated by a FDM rapid prototyping machine in different layer orientations with variations in internal geometrical structure. The 0° orientation where layers were deposited along the length of the samples displayed superior strength and impact resistance over all the other orientations. The anisotropic properties were probably caused by weak interlayer bonding and interlayer porosity.Keywords: building orientation, compression strength, rapid prototyping, tensile strength
Procedia PDF Downloads 6971580 A Review: Recycled Materials Used in Construction
Authors: Oghenerukome Akponovo, Lynda I. Onyebuchukwu
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Construction waste, along with that of many other industries, contributes significantly to the world's annual solid waste totals. Most of these materials, such as ash from rice hulls, slags, cement kiln dust, tire ash, plastic waste (PW), and silica fumes, end up in landfills or waterways. Some of them might even end up polluting the air from high in the atmosphere. It's sustainable, cheap, and environmentally friendly to recycle these items into new building supplies. When constructing a "Green" structure, the materials employed have the potential to either exacerbate environmental imbalance or maintain a stable ecosystem. The purpose of this research is to take stock of what is already known about recycling's potential in the construction industry and to identify its deficiencies. Therefore, this study systematically reviews the wide range of recycled materials that go into building construction. Recognizing that the construction industry's use of recycled materials has an influence on the environment and that investigating these materials may have a substantial economic impact if they were discoveredKeywords: building, construction, recycled materials, waste management
Procedia PDF Downloads 1071579 Evaluation of Polyurethane-Bonded Particleboard Manufactured with Eucalyptus Sp. and Bi-Oriented Polypropylene Wastes
Authors: Laurenn Borges de Macedo, Fabiane Salles Ferro, Tiago Hendrigo de Almeida, Gérson Moreira de Lima, André Luiz Christoforo, Francisco Antonio Rocco Lahr
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The growth of the furniture manufacturing industry is one of the fundamental factors contributing to the growth of the particleboard industry. The use of recycled products into particleboards can contribute to the forest conservation, in addition to achieve a high quality sustainable product with low-cost production. This work investigates the effect of bi-oriented polypropylene (BOPP) waste particles and sealing product on the physical and mechanical properties of Eucalyptus sp. particleboards fabricated with a castor oil based polyurethane resin. Among the factors, only the seal coating was statistically significant. The wood panels of Treatment 2 were classified as H1, based on the internal bond strength and elastic modulus results data required by ANSI A208.1:1999. The bending strength data did not reach the minimum values recommended by NBR 14810:2006 and ANSI A208.1:1999. The thickness swelling data for 2h immersed in water achieved the standard requirement levels. High-density panels were achieved revealing their potential use in variety of particleboard applications.Keywords: BOPP, mechanical properties, particleboards, physical properties
Procedia PDF Downloads 3721578 Degradation of Poly -β- Hydroxybutyrate by Trichoderma asperellum
Authors: Nuha Mansour Alhazmi
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Replacement of petro-based plastics by a biodegradable plastic are vastly growing process. Poly-β-hydroxybutyrate (PHB) is a biodegradable biopolymer, synthesized by some bacterial genera. The objective of the current study is to explore the ability of some fungi to biodegrade PHB. The degradation of (PHB) was detected in Petri dish by the formation of a clear zone around the fungal colonies due to the production of depolymerase enzyme which has an interesting role in the PHB degradation process. Among 10 tested fungi, the most active PHB biodegraded fungi were identified as Trichoderma asperellum using morphological and molecular characters. The highest PHB degradation was at 25°C, pH 7.5 after 7 days of incubation for the tested fungi. Finally, the depolymerase enzyme was isolated, purified using column chromatography and characterized. In conclusion, PHB can be biodegraded in solid and liquid medium using depolymerase enzyme from T. asperellum.Keywords: degradation, depolymerase enzyme, PHB, Trichoderma asperellum
Procedia PDF Downloads 1811577 Composition, Velocity, and Mass of Projectiles Generated from a Chain Shot Event
Authors: Eric Shannon, Mark J. McGuire, John P. Parmigiani
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A hazard associated with the use of timber harvesters is chain shot. Harvester saw chain is subjected to large dynamic mechanical stresses which can cause it to fracture. The resulting open loop of saw chain can fracture a second time and create a projectile consisting of several saw-chain links referred to as a chain shot. Its high kinetic energy enables it to penetrate operator enclosures and be a significant hazard. Accurate data on projectile composition, mass, and speed are needed for the design of both operator enclosures resistant to projectile penetration and for saw chain resistant to fracture. The work presented here contributes to providing this data through the use of a test machine designed and built at Oregon State University. The machine’s enclosure is a standard shipping container. To safely contain any anticipated chain shot, the container was lined with both 9.5 mm AR500 steel plates and 50 mm high-density polyethylene (HDPE). During normal operation, projectiles are captured virtually undamaged in the HDPE enabling subsequent analysis. Standard harvester components are used for bar mounting and chain tensioning. Standard guide bars and saw chains are used. An electric motor with flywheel drives the system. Testing procedures follow ISO Standard 11837. Chain speed at break was approximately 45.5 m/s. Data was collected using both a 75 cm solid bar (Oregon 752HSFB149) and 90 cm solid bar (Oregon 902HSFB149). Saw chains used were 89 Drive Link .404”-18HX loops made from factory spools. Standard 16-tooth sprockets were used. Projectile speed was measured using both a high-speed camera and a chronograph. Both rotational and translational kinetic energy are calculated. For this study 50 chain shot events were executed. Results showed that projectiles consisted of a variety combinations of drive links, tie straps, and cutter links. Most common (occurring in 60% of the events) was a drive-link / tie-strap / drive-link combination having a mass of approximately 10.33 g. Projectile mass varied from a minimum of 2.99 g corresponding to a drive link only to a maximum of 18.91 g corresponding to a drive-link / tie-strap / drive-link / cutter-link / drive-link combination. Projectile translational speed was measured to be approximately 270 m/s and rotational speed of approximately 14000 r/s. The calculated translational and rotational kinetic energy magnitudes each average over 600 J. This study provides useful information for both timber harvester manufacturers and saw chain manufacturers to design products that reduce the hazards associated with timber harvesting.Keywords: chain shot, timber harvesters, safety, testing
Procedia PDF Downloads 1461576 Evaluation of Coal Quality and Geomechanical Moduli Using Core and Geophysical Logs: Study from Middle Permian Barakar Formation of Gondwana Coalfield
Authors: Joyjit Dey, Souvik Sen
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Middle Permian Barakar formation is the major economic coal bearing unit of vast east-west trending Damodar Valley basin of Gondwana coalfield. Primary sedimentary structures were studied from the core holes, which represent majorly four facies groups: sandstone dominated facies, sandstone-shale heterolith facies, shale facies and coal facies. Total eight major coal seams have been identified with the bottom most seam being the thickest. Laterally, continuous coal seams were deposited in the calm and quiet environment of extensive floodplain swamps. Channel sinuosity and lateral channel migration/avulsion results in lateral facies heterogeneity and coal splitting. Geophysical well logs (Gamma-Resistivity-Density logs) have been used to establish the vertical and lateral correlation of various litho units field-wide, which reveals the predominance of repetitive fining upwards cycles. Well log data being a permanent record, offers a strong foundation for generating log based property evaluation and helps in characterization of depositional units in terms of lateral and vertical heterogeneity. Low gamma, high resistivity, low density is the typical coal seam signatures in geophysical logs. Here, we have used a density cutoff of 1.6 g/cc as a primary discriminator of coal and the same has been employed to compute various coal assay parameters, which are ash, fixed carbon, moisture, volatile content, cleat porosity, vitrinite reflectance (VRo%), which were calibrated with the laboratory based measurements. The study shows ash content and VRo% increase from west to east (towards basin margin), while fixed carbon, moisture and volatile content increase towards west, depicting increased coal quality westwards. Seam wise cleat porosity decreases from east to west, this would be an effect of overburden, as overburden pressure increases westward with the deepening of basin causing more sediment packet deposited on the western side of the study area. Coal is a porous, viscoelastic material in which velocity and strain both change nonlinearly with stress, especially for stress applied perpendicular to the bedding plane. Usually, the coal seam has a high velocity contrast relative to its neighboring layers. Despite extensive discussion of the maceral and chemical properties of coal, its elastic characteristics have received comparatively little attention. The measurement of the elastic constants of coal presents many difficulties: sample-to-sample inhomogeneity and fragility and velocity dependence on stress, orientation, humidity, and chemical content. In this study, a conclusive empirical equation VS= 0.80VP-0.86 has been used to model shear velocity from compression velocity. Also the same has been used to compute various geomechanical moduli. Geomech analyses yield a Poisson ratio of 0.348 against coals. Average bulk modulus value is 3.97 GPA, while average shear modulus and Young’s modulus values are coming out as 1.34 and 3.59 GPA respectively. These middle Permian Barakar coals show an average 23.84 MPA uniaxial compressive strength (UCS) with 4.97 MPA cohesive strength and 0.46 as friction coefficient. The output values of log based proximate parameters and geomechanical moduli suggest a medium volatile Bituminous grade for the studied coal seams, which is found in the laboratory based core study as well.Keywords: core analysis, coal characterization, geophysical log, geo-mechanical moduli
Procedia PDF Downloads 2261575 Numerical Study of Natural Convection of a Localized Heat Source at the up of a Nanofluid-Filled Enclosure
Authors: Marziyeh Heydari, Hossein Shokouhmand
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This article presents a numerical study of natural convection of a heat source embedded on the up wall of an enclosure filled with nanofluid. The bottom and vertical walls of the enclosure are maintained at a relatively low temperature. The type of nanofluid and solid volume fraction of nanoparticle on the heat transfer performance is studied. The results indicated that adding nanoparticle into pure paraffin improves heat transfer. The results are presented over a wide range of Rayleigh numbers(Ra=〖10〗^3 〖-10〗^5), the volume fraction of nanoparticles (0≤ɸ≤0.4%). For an enclosure, the Nusselt number of a cu-paraffin nanofluid was reduced by increasing the volume fraction of nanoparticles above 0.2%.Keywords: nanofluid, heat transfer, heat source, enclosure
Procedia PDF Downloads 3101574 Co-pyrolysis of Sludge and Kaolin/Zeolite to Stabilize Heavy Metals
Authors: Qian Li, Zhaoping Zhong
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Sewage sludge, a typical solid waste, has inevitably been produced in enormous quantities in China. Still worse, the amount of sewage sludge produced has been increasing due to rapid economic development and urbanization. Compared to the conventional method to treat sewage sludge, pyrolysis has been considered an economic and ecological technology because it can significantly reduce the sludge volume, completely kill pathogens, and produce valuable solid, gas, and liquid products. However, the large-scale utilization of sludge biochar has been limited due to the considerable risk posed by heavy metals in the sludge. Heavy metals enriched in pyrolytic biochar could be divided into exchangeable, reducible, oxidizable, and residual forms. The residual form of heavy metals is the most stable and cannot be used by organisms. Kaolin and zeolite are environmentally friendly inorganic minerals with a high surface area and heat resistance characteristics. So, they exhibit the enormous potential to immobilize heavy metals. In order to reduce the risk of leaching heavy metals in the pyrolysis biochar, this study pyrolyzed sewage sludge mixed with kaolin/zeolite in a small rotary kiln. The influences of additives and pyrolysis temperature on the leaching concentration and morphological transformation of heavy metals in pyrolysis biochar were investigated. The potential mechanism of stabilizing heavy metals in the co-pyrolysis of sludge blended with kaolin/zeolite was explained by scanning electron microscopy, X-ray diffraction, and specific surface area and porosity analysis. The European Community Bureau of Reference sequential extraction procedure has been applied to analyze the forms of heavy metals in sludge and pyrolysis biochar. All the concentrations of heavy metals were examined by flame atomic absorption spectrophotometry. Compared with the proportions of heavy metals associated with the F4 fraction in pyrolytic carbon prepared without additional agents, those in carbon obtained by co-pyrolysis of sludge and kaolin/zeolite increased. Increasing the additive dosage could improve the proportions of the stable fraction of various heavy metals in biochar. Kaolin exhibited a better effect on stabilizing heavy metals than zeolite. Aluminosilicate additives with excellent adsorption performance could capture more released heavy metals during sludge pyrolysis. Then heavy metal ions would react with the oxygen ions of additives to form silicate and aluminate, causing the conversion of heavy metals from unstable fractions (sulfate, chloride, etc.) to stable fractions (silicate, aluminate, etc.). This study reveals that the efficiency of stabilizing heavy metals depends on the formation of stable mineral compounds containing heavy metals in pyrolysis biochar.Keywords: co-pyrolysis, heavy metals, immobilization mechanism, sewage sludge
Procedia PDF Downloads 661573 Contribution of Exchange-correlation Effects on Weakly Relativistic Plasma Expansion
Authors: Rachid Fermous, Rima Mebrek
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Plasma expansion is an important physical process that takes place in laser interactions with solid targets. Within a self-similar model for the hydrodynamic multi-fluid equations, we investigated the expansion of dense plasma. The weakly relativistic electrons are produced by ultra-intense laser pulses, while ions are supposed to be in a non-relativistic regime. It is shown that dense plasma expansion is found to be governed mainly by quantum contributions in the fluid equations that originate from the degenerate pressure in addition to the nonlinear contributions from exchange and correlation potentials. The quantum degeneracy parameter profile provides clues to set the limit between under-dense and dense relativistic plasma expansions at a given density and temperature.Keywords: plasma expansion, quantum degeneracy, weakly relativistic, under-dense plasma
Procedia PDF Downloads 871572 Traffic Forecasting for Open Radio Access Networks Virtualized Network Functions in 5G Networks
Authors: Khalid Ali, Manar Jammal
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In order to meet the stringent latency and reliability requirements of the upcoming 5G networks, Open Radio Access Networks (O-RAN) have been proposed. The virtualization of O-RAN has allowed it to be treated as a Network Function Virtualization (NFV) architecture, while its components are considered Virtualized Network Functions (VNFs). Hence, intelligent Machine Learning (ML) based solutions can be utilized to apply different resource management and allocation techniques on O-RAN. However, intelligently allocating resources for O-RAN VNFs can prove challenging due to the dynamicity of traffic in mobile networks. Network providers need to dynamically scale the allocated resources in response to the incoming traffic. Elastically allocating resources can provide a higher level of flexibility in the network in addition to reducing the OPerational EXpenditure (OPEX) and increasing the resources utilization. Most of the existing elastic solutions are reactive in nature, despite the fact that proactive approaches are more agile since they scale instances ahead of time by predicting the incoming traffic. In this work, we propose and evaluate traffic forecasting models based on the ML algorithm. The algorithms aim at predicting future O-RAN traffic by using previous traffic data. Detailed analysis of the traffic data was carried out to validate the quality and applicability of the traffic dataset. Hence, two ML models were proposed and evaluated based on their prediction capabilities.Keywords: O-RAN, traffic forecasting, NFV, ARIMA, LSTM, elasticity
Procedia PDF Downloads 2261571 Research on Spatial Morphology and Protection of Traditional Rural Settlements Based on Space Syntax: Taking Xiazhuang Village and Shijia Village in Huzhou as Example
Authors: Shenpu Liu
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Space syntax, a paradigm of the urban research, which manifests people’s intuitive and abstract perception of a material space with a solid mathematical way, explores how space represents its social characteristics. Taking Xiazhuang village and Shijia Village in Huzhou as an example and focusing on inward structure and street space, this article recognizes the connotative significance of the settlement with the aid of space syntax theory and quantitative analysis method from the perspective of spatial configuration to present relevant suggestions for its future planning and provides references for traditional rural settlement protection.Keywords: Shijia village, space configuration, space syntax, traditional rural settlement, Xiazhuang village
Procedia PDF Downloads 2381570 Modal Analysis of FGM Plates Using Finite Element Method
Authors: S. J. Shahidzadeh Tabatabaei, A. M. Fattahi
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Modal analysis of an FGM plate containing the ceramic phase of Al2O3 and metal phase of stainless steel 304 was performed using ABAQUS, with the assumptions that the material has an elastic mechanical behavior and its Young modulus and density are varying in thickness direction. For this purpose, a subroutine was written in FORTRAN and linked with ABAQUS. First, a simulation was performed in accordance to other researcher’s model, and then after comparing the obtained results, the accuracy of the present study was verified. The obtained results for natural frequency and mode shapes indicate good performance of user-written subroutine as well as FEM model used in present study. After verification of obtained results, the effect of clamping condition and the material type (i.e. the parameter n) was investigated. In this respect, finite element analysis was carried out in fully clamped condition for different values of n. The results indicate that the natural frequency decreases with increase of n, since with increase of n, the amount of ceramic phase in FGM plate decreases, while the amount of metal phase increases, leading to decrease of the plate stiffness and hence, natural frequency, as the Young modulus of Al2O3 is equal to 380 GPa and the Young modulus of stainless steel 304 is equal to 207 GPa.Keywords: FGM plates, modal analysis, natural frequency, finite element method
Procedia PDF Downloads 3421569 Effective Stiffness, Permeability, and Reduced Wall Shear Stress of Highly Porous Tissue Engineering Scaffolds
Authors: Hassan Mohammadi Khujin
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Tissue engineering is the science of tissues and complex organs creation using scaffolds, cells and biologically active components. Most cells require scaffolds to grow and proliferate. These temporary support structures for tissue regeneration are later replaced with extracellular matrix produced inside the body. Recent advances in additive manufacturing methods allow production of highly porous, complex three dimensional scaffolds suitable for cell growth and proliferation. The current paper investigates the mechanical properties, including elastic modulus and compressive strength, as well as fluid flow dynamics, including permeability and flow-induced shear stress of scaffolds with four triply periodic minimal surface (TPMS) configurations, namely the Schwarz primitive, the Schwarz diamond, the gyroid, and the Neovius structures. Higher porosity in all scaffold types resulted in lower mechanical properties. The permeability of the scaffolds was determined using Darcy's law with reference to geometrical parameters and the pressure drop derived from the computational fluid dynamics (CFD) analysis. Higher porosity enhanced permeability and reduced wall shear stress in all scaffold designs.Keywords: highly porous scaffolds, tissue engineering, finite elements analysis, CFD analysis
Procedia PDF Downloads 761568 The Utilization of FSI Technique and Two-Way Particle Coupling System on Particle Dynamics in the Human Alveoli
Authors: Hassan Athari, Abdurrahim Bolukbasi, Dogan Ciloglu
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This study represented the respiratory alveoli system, and determined the trajectory of inhaled particles more accurately using the modified three-dimensional model with deformable walls of alveoli. The study also considered the tissue tension in the model to demonstrate the effect of lung. Tissue tensions are transferred by the lung parenchyma and produce the pressure gradient. This load expands the alveoli and establishes a sub-ambient (vacuum) pressure within the lungs. Thus, at the alveolar level, the flow field and movement of alveoli wall lead to an integrated effect. In this research, we assume that the three-dimensional alveolus has a visco-elastic tissue (walls). For accurate investigation of pulmonary tissue mechanical properties on particle transport and alveolar flow field, the actual relevance between tissue movement and airflow is solved by two-way FSI (Fluid Structure Interaction) simulation technique in the alveolus. Therefore, the essence of real simulation of pulmonary breathing mechanics can be achieved by developing a coupled FSI computational model. We, therefore conduct a series of FSI simulations over a range of tissue models and breathing rates. As a result, the fluid flows and streamlines have changed during present flexible model against the rigid models and also the two-way coupling particle trajectories have changed against the one-way particle coupling.Keywords: FSI, two-way particle coupling, alveoli, CDF
Procedia PDF Downloads 2571567 Isogeometric Topology Optimization in Cracked Structures Design
Authors: Dongkyu Lee, Thanh Banh Thien, Soomi Shin
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In the present study, the isogeometric topology optimization is proposed for cracked structures through using Solid Isotropic Material with Penalization (SIMP) as a design model. Design density variables defined in the variable space are used to approximate the element analysis density by the bivariate B-spline basis functions. The mathematical formulation of topology optimization problem solving minimum structural compliance is an alternating active-phase algorithm with the Gauss-Seidel version as an optimization model of optimality criteria. Stiffness and adjoint sensitivity formulations linked to strain energy of cracked structure are proposed in terms of design density variables. Numerical examples demonstrate interactions of topology optimization to structures design with cracks.Keywords: topology optimization, isogeometric, NURBS, design
Procedia PDF Downloads 4921566 Synthesis of LiMₓMn₂₋ₓO₄ Doped Co, Ni, Cr and Its Characterization as Lithium Battery Cathode
Authors: Dyah Purwaningsih, Roto Roto, Hari Sutrisno
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Manganese dioxide (MnO₂) and its derivatives are among the most widely used materials for the positive electrode in both primary and rechargeable lithium batteries. The MnO₂ derivative compound of LiMₓMn₂₋ₓO₄ (M: Co, Ni, Cr) is one of the leading candidates for positive electrode materials in lithium batteries as it is abundant, low cost and environmentally friendly. Over the years, synthesis of LiMₓMn₂₋ₓO₄ (M: Co, Ni, Cr) has been carried out using various methods including sol-gel, gas condensation, spray pyrolysis, and ceramics. Problems with these various methods persist including high cost (so commercially inapplicable) and must be done at high temperature (environmentally unfriendly). This research aims to: (1) synthesize LiMₓMn₂₋ₓO₄ (M: Co, Ni, Cr) by reflux technique; (2) develop microstructure analysis method from XRD Powder LiMₓMn₂₋ₓO₄ data with the two-stage method; (3) study the electrical conductivity of LiMₓMn₂₋ₓO₄. This research developed the synthesis of LiMₓMn₂₋ₓO₄ (M: Co, Ni, Cr) with reflux. The materials consisting of Mn(CH₃COOH)₂. 4H₂O and Na₂S₂O₈ were refluxed for 10 hours at 120°C to form β-MnO₂. The doping of Co, Ni and Cr were carried out using solid-state method with LiOH to form LiMₓMn₂₋ₓO₄. The instruments used included XRD, SEM-EDX, XPS, TEM, SAA, TG/DTA, FTIR, LCR meter and eight-channel battery analyzer. Microstructure analysis of LiMₓMn₂₋ₓO₄ was carried out on XRD powder data by two-stage method using FullProf program integrated into WinPlotR and Oscail Program as well as on binding energy data from XPS. The morphology of LiMₓMn₂₋ₓO₄ was studied with SEM-EDX, TEM, and SAA. The thermal stability test was performed with TG/DTA, the electrical conductivity was studied from the LCR meter data. The specific capacity of LiMₓMn₂₋ₓO₄ as lithium battery cathode was tested using an eight-channel battery analyzer. The results showed that the synthesis of LiMₓMn₂₋ₓO₄ (M: Co, Ni, Cr) was successfully carried out by reflux. The optimal temperature of calcination is 750°C. XRD characterization shows that LiMn₂O₄ has a cubic crystal structure with Fd3m space group. By using the CheckCell in the WinPlotr, the increase of Li/Mn mole ratio does not result in changes in the LiMn₂O₄ crystal structure. The doping of Co, Ni and Cr on LiMₓMn₂₋ₓO₄ (x = 0.02; 0.04; 0; 0.6; 0.08; 0.10) does not change the cubic crystal structure of Fd3m. All the formed crystals are polycrystals with the size of 100-450 nm. Characterization of LiMₓMn₂₋ₓO₄ (M: Co, Ni, Cr) microstructure by two-stage method shows the shrinkage of lattice parameter and cell volume. Based on its range of capacitance, the conductivity obtained at LiMₓMn₂₋ₓO₄ (M: Co, Ni, Cr) is an ionic conductivity with varying capacitance. The specific battery capacity at a voltage of 4799.7 mV for LiMn₂O₄; Li₁.₀₈Mn₁.₉₂O₄; LiCo₀.₁Mn₁.₉O₄; LiNi₀.₁Mn₁.₉O₄ and LiCr₀.₁Mn₁.₉O₄ are 88.62 mAh/g; 2.73 mAh/g; 89.39 mAh/g; 85.15 mAh/g; and 1.48 mAh/g respectively.Keywords: LiMₓMn₂₋ₓO₄, solid-state, reflux, two-stage method, ionic conductivity, specific capacity
Procedia PDF Downloads 1931565 Solid State Drive End to End Reliability Prediction, Characterization and Control
Authors: Mohd Azman Abdul Latif, Erwan Basiron
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A flaw or drift from expected operational performance in one component (NAND, PMIC, controller, DRAM, etc.) may affect the reliability of the entire Solid State Drive (SSD) system. Therefore, it is important to ensure the required quality of each individual component through qualification testing specified using standards or user requirements. Qualification testing is time-consuming and comes at a substantial cost for product manufacturers. A highly technical team, from all the eminent stakeholders is embarking on reliability prediction from beginning of new product development, identify critical to reliability parameters, perform full-blown characterization to embed margin into product reliability and establish control to ensure the product reliability is sustainable in the mass production. The paper will discuss a comprehensive development framework, comprehending SSD end to end from design to assembly, in-line inspection, in-line testing and will be able to predict and to validate the product reliability at the early stage of new product development. During the design stage, the SSD will go through intense reliability margin investigation with focus on assembly process attributes, process equipment control, in-process metrology and also comprehending forward looking product roadmap. Once these pillars are completed, the next step is to perform process characterization and build up reliability prediction modeling. Next, for the design validation process, the reliability prediction specifically solder joint simulator will be established. The SSD will be stratified into Non-Operating and Operating tests with focus on solder joint reliability and connectivity/component latent failures by prevention through design intervention and containment through Temperature Cycle Test (TCT). Some of the SSDs will be subjected to the physical solder joint analysis called Dye and Pry (DP) and Cross Section analysis. The result will be feedbacked to the simulation team for any corrective actions required to further improve the design. Once the SSD is validated and is proven working, it will be subjected to implementation of the monitor phase whereby Design for Assembly (DFA) rules will be updated. At this stage, the design change, process and equipment parameters are in control. Predictable product reliability at early product development will enable on-time sample qualification delivery to customer and will optimize product development validation, effective development resource and will avoid forced late investment to bandage the end-of-life product failures. Understanding the critical to reliability parameters earlier will allow focus on increasing the product margin that will increase customer confidence to product reliability.Keywords: e2e reliability prediction, SSD, TCT, solder joint reliability, NUDD, connectivity issues, qualifications, characterization and control
Procedia PDF Downloads 1741564 Numerical Investigation of Beam-Columns Subjected to Non-Proportional Loadings under Ambient Temperature Conditions
Authors: George Adomako Kumi
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The response of structural members, when subjected to various forms of non-proportional loading, plays a major role in the overall stability and integrity of a structure. This research seeks to present the outcome of a finite element investigation conducted by the use of finite element programming software ABAQUS to validate the experimental results of elastic and inelastic behavior and strength of beam-columns subjected to axial loading, biaxial bending, and torsion under ambient temperature conditions. The application of the rigorous and highly complicated ABAQUS finite element software will seek to account for material, non-linear geometry, deformations, and, more specifically, the contact behavior between the beam-columns and support surfaces. Comparisons of the three-dimensional model with the results of actual tests conducted and results from a solution algorithm developed through the use of the finite difference method will be established in order to authenticate the veracity of the developed model. The results of this research will seek to provide structural engineers with much-needed knowledge about the behavior of steel beam columns and their response to various non-proportional loading conditions under ambient temperature conditions.Keywords: beam-columns, axial loading, biaxial bending, torsion, ABAQUS, finite difference method
Procedia PDF Downloads 1801563 Hardness Analysis of Samples of Friction Stir Welded Joints of (Al-Cu)
Authors: Upamanyu Majumder, Angshuman Das
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Friction Stir Welding (FSW) is a Solid-State joining process. Unlike fusion welding techniques it does not involve operation above the melting point temperature of metals, but above the re-crystallization temperature. FSW also does not involve fusion of other material. FSW of ALUMINIUM has been commercialized and recent studies on joining dissimilar metals have been studied. Friction stir welding was introduced and patented in 1991 by The Welding Institute. For this paper, a total of nine samples each of copper and ALUMINIUM(Dissimilar metals) were welded using FSW process and Vickers Hardness were conducted on each of the samples.Keywords: friction stir welding (FSW), recrystallization temperature, dissimilar metals, aluminium-copper, Vickers hardness test
Procedia PDF Downloads 3551562 The Effects of Inulin on the Stabilization and Stevioside as Sugar-Replacer of Sourcherry Juice-Milk Mixture
Authors: S. Teimouri, S. Abbasi
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Milk-fruit juice mixture is a type of soft drinks, which can be produced by mixing milk with pieces of fruits, fruit juices, or fruit juices concentrates. The major problem of these products, mainly the acidic ones, is phase separation which occurs during formulation and storage due to the aggregation of caseins at low pH Short-chain inulin (CLR), long-chain inulin (TEX), native inulin (IQ) and Long-chain inulin (TEX) and short-chain inulin (CLR) combined in different proportions (2o:80, 50:50, and 80:20) were added (2-10 %) to sourcherry juice-milk mixture and their stabilization mechanisms were studied with using rheological and microstructural observations. Stevioside as a bio-sweetener and sugar-replacer was added at last step. Finally, sensory analyses were taken place on stabilized samples. According to the findings, TEX stabilized the mixture at concentration of 8%. MIX and IQ reduced phase separation at high concentration but had not complete effect on stabilization. CLR did not effect on stabilization. Rheological changes and inulin aggregates formation were not observed in CLR samples during the one month storage period. However TEX, MIX and IQ samples formed inulin aggregates and became more thixotropic, elastic and increased the viscosity of mixture. The rate of the inulin aggregates formation and viscosity increasing was in the following order TEX > MIX > IQ. Consequently the mixture which stabilized with inulin and sweetened with stevioside had the prebiotic properties which may suggest to diabetic patients and children.Keywords: prebiotic, inulin, casein, stabilization, stevioside
Procedia PDF Downloads 2741561 Computer Aided Assembly Attributes Retrieval Methods for Automated Assembly Sequence Generation
Authors: M. V. A. Raju Bahubalendruni, Bibhuti Bhusan Biswal, B. B. V. L. Deepak
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Achieving an appropriate assembly sequence needs deep verification for its physical feasibility. For this purpose, industrial engineers use several assembly predicates; namely, liaison, geometric feasibility, stability and mechanical feasibility. However, testing an assembly sequence for these predicates requires huge assembly information. Extracting such assembly information from an assembled product is a time consuming and highly skillful task with complex reasoning methods. In this paper, computer aided methods are proposed to extract all the necessary assembly information from computer aided design (CAD) environment in order to perform the assembly sequence planning efficiently. These methods use preliminary capabilities of three-dimensional solid modelling and assembly modelling methods used in CAD software considering equilibrium laws of physical bodies.Keywords: assembly automation, assembly attributes, assembly, CAD
Procedia PDF Downloads 3051560 The Influence of Marxism Theory in Malaka's Perspective in Indonesia
Authors: Farhan Alam Farhan Alam, Fatah Nugroho, Setyawan Wahyu Pradana
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Tan Malaka was a great Indonesian Marxism thinker. His idea of Marxism give encouragement to the struggle for Indonesian independence. Furthermore, it refers to what Marx said as the flexibility of a Marxist. Tan Malaka developed the Marxist theory against what have already existed so that Marxism can be harmonized and compatible with the context of Indonesia. For example, Tan Malaka initiated the cooperation between the Marxist movement and Pan-Islamism. The collaboration of Islam with Marxism which is so contradictive at that time was seen by Tan Malaka as a necessity in order to against capitalism. By using study literature and historiography methods, this paper attempts to analyze the application of the Marxism theory in the Tan Malaka’s perspective in Indonesia today in order to counter capitalism currently. His perspective combines Marxism with Islam as a solid collaboration of ideology.Keywords: Indonesia, Marxism, Islam, Marxist theory, Tan Malaka
Procedia PDF Downloads 3061559 Characterization of Thixoformed AlSi12 Alloy with the Addition of Trace Amounts of Silver
Authors: Nursen Saklakoglu, Adnan Turker
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The main objective of this study is to reveal the effect of the Thixoforming process on the microstructure and mechanical properties of the AlSi12 alloy with trace amounts of silver. It is concluded that Thixoforming has an important effect on the morphology of intermetallics and Si formation, as well as globular α-Al morphology. The intermetallics have been fractured during thixoforming. It is believed that the fine distribution of the intermetallics is one mechanism for the improved mechanical properties of Thixoformed alloys. The discrete Si particles have been observed during both isothermal heating to the semi-solid range and Thixoforming, also have an important effect on mechanical properties. The Thixoforming process has a greater effect on hardness than the addition of Ag does.Keywords: AlSi alloys, intermetallic phases, mechanical properties trace element, silver, thixoforming
Procedia PDF Downloads 3261558 Act East Policy and the Politics of the Non-Recognized Thai-Indian Diasporic Community in Thailand
Authors: Ruchi Agarwal
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The Indian diaspora in Thailand is as ethnically diverse as any other country. Although a relatively small community, the Indian diaspora has long established its roots, some with their fifth generation now living in Thailand. The community has a solid social and economic standing recognized by the host country but lacks connections with its ethnic roots in the home country. The biggest dilemma faced by the younger generation of the Indian diasporic community is the identity crisis. Regardless of being born and brought up in Thailand and possessing Thai citizenship, they do not get recognition as Thais by their Thai counterparts. However, with the Act Asia Policy of the Indian government, there has been an increase in social and political activities organized by old and new Indian associations, bringing new hopes of recognizing the Thai-Indian diasporic community.Keywords: Indian, Thailand, diaspora, Act East Policy, Thai
Procedia PDF Downloads 1531557 Computational Investigation of Gas-Solid Flow in High Pressure High Temperature Filter
Authors: M. H. Alhajeri, Hamad M. Alhajeri, A. H. Alenezi
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This paper reports a Computational Fluid Dynamics (CFD) investigation for a high-temperature high-pressure filtration (ceramic candle filter). However, parallel flow to the filter is considered in this study. Different face (filtration) velocities are examined using the CFD code, FLUENT. Different sizes of particles are tracked through the domain to find the height at which the particles will impinge on the filter surface. Furthermore, particle distribution around the filter (or filter cake) is studied to design efficient cleaning mechanisms. Gravity effect to the particles with various inlet velocities and pressure drop are both considered. In the CFD study, it is found that the gravity influence should not be ignored if the particle sizes exceed 1 micron.Keywords: fluid flow, CFD, filtration, HTHP
Procedia PDF Downloads 2041556 Investigating The Effects of Utilizing Different Curing Agents on High-Performance Concrete
Authors: Mostafa M. Ahmed, Kotaro Nose, Takashi Fujii, Toshiki Ayano
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The Study shed the light on the effects of employing varied curing agents (No.1-No.6): bleeding water, and sprinkling water, aqueous basic silica compound, modified acrylic resin, the emulsion of solid wax and nonionic surfactant, and water-based paraffin wax, on the properties of high-performance concrete (HPC) in comparison with the cured specimens according to the standard curing at 20 ± 3°C (JIS A 0203:2019). The specimens cured in accordance with standard curing exhibit a better compressive strength and higher freeze-thaw resistance compared to most non-standard-cured samples.Keywords: curing agents, high-performance concrete, compressive strength, cumulative scaling, freeze-thaw resistance
Procedia PDF Downloads 771555 Effect of Synthesis Method on Structural, Morphological Properties of Zr0.8Y0.2-xLax Oxides (x=0, 0.1, 0.2)
Authors: Abdelaziz Ghrib, Samir Hattali, Mouloud Ghrib, Mohamed Lamine Aouissia, David Ruch
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In the present study, the solid solutions with a chemical composition of Zr0.8Y0.2-xLaxO2 (x=0, 0.1, 0.2) were synthesized via two routes, by hydrothermal method using NaOH as precipitating agent at 230°C for 15h and by the sol–gel process using citric acid as complexing agent. Compounds have been characterized by powder X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Thermo gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA) techniques for appropriate characterization of the distinct thermal events occurring during synthesis. All the compounds crystallize in cubic fluorite structure, as indicated by X-ray diffraction studie. The microstructure of oxides synthesized by sol-gel showed porosity that increased with the lanthanum La3+ contents compared to hydrothermal method which gives a single crystal oxide.Keywords: oxide, hydrothermal, rare earth, solubility, sol-gel, ternary mixture
Procedia PDF Downloads 6421554 Liquid Food Sterilization Using Pulsed Electric Field
Authors: Tanmaya Pradhan, K. Midhun, M. Joy Thomas
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Increasing the shelf life and improving the quality are important objectives for the success of packaged liquid food industry. One of the methods by which this can be achieved is by deactivating the micro-organisms present in the liquid food through pasteurization. Pasteurization is done by heating, but some serious disadvantages such as the reduction in food quality, flavour, taste, colour, etc. were observed because of heat treatment, which leads to the development of newer methods instead of pasteurization such as treatment using UV radiation, high pressure, nuclear irradiation, pulsed electric field, etc. In recent years the use of the pulsed electric field (PEF) for inactivation of the microbial content in the food is gaining popularity. PEF uses a very high electric field for a short time for the inactivation of microorganisms, for which we require a high voltage pulsed power source. Pulsed power sources used for PEF treatments are usually in the range of 5kV to 50kV. Different pulse shapes are used, such as exponentially decaying and square wave pulses. Exponentially decaying pulses are generated by high power switches with only turn-on capacity and, therefore, discharge the total energy stored in the capacitor bank. These pulses have a sudden onset and, therefore, a high rate of rising but have a very slow decay, which yields extra heat, which is ineffective in microbial inactivation. Square pulses can be produced by an incomplete discharge of a capacitor with the help of a switch having both on/off control or by using a pulse forming network. In this work, a pulsed power-based system is designed with the help of high voltage capacitors and solid-state switches (IGBT) for the inactivation of pathogenic micro-organism in liquid food such as fruit juices. The high voltage generator is based on the Marx generator topology, which can produce variable amplitude, frequency, and pulse width according to the requirements. Liquid food is treated in a chamber where pulsed electric field is produced between stainless steel electrodes using the pulsed output voltage of the supply. Preliminary bacterial inactivation tests were performed by subjecting orange juice inoculated with Escherichia Coli bacteria. With the help of the developed pulsed power source and the chamber, the inoculated orange has been PEF treated. The voltage was varied to get a peak electric field up to 15kV/cm. For a total treatment time of 200µs, a 30% reduction in the bacterial count has been observed. The detailed results and analysis will be presented in the final paper.Keywords: Escherichia coli bacteria, high voltage generator, microbial inactivation, pulsed electric field, pulsed forming line, solid-state switch
Procedia PDF Downloads 1841553 Influence of Kinematic, Physical and Mechanical Structure Parameters on Aeroelastic GTU Shaft Vibrations in Magnetic Bearings
Authors: Evgeniia V. Mekhonoshina, Vladimir Ya. Modorskii, Vasilii Yu. Petrov
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At present, vibrations of rotors of gas transmittal unit evade sustainable forecasting. This paper describes elastic oscillation modes in resilient supports and rotor impellers modeled during computational experiments with regard to interference in the system of gas-dynamic flow and compressor rotor. Verification of aeroelastic approach was done on model problem of interaction between supersonic jet in shock tube with deformed plate. ANSYS 15.0 engineering analysis system was used as a modeling tool of numerical simulation in this paper. Finite volume method for gas dynamics and finite elements method for assessment of the strain stress state (SSS) components were used as research methods. Rotation speed and material’s elasticity modulus varied during calculations, and SSS components and gas-dynamic parameters in the dynamic system of gas-dynamic flow and compressor rotor were evaluated. The analysis of time dependence demonstrated that gas-dynamic parameters near the rotor blades oscillate at 200 Hz, and SSS parameters at the upper blade edge oscillate four times higher, i.e. with blade frequency. It has been detected that vibration amplitudes correction in the test points at magnetic bearings by aeroelasticity may correspond up to 50%, and about -π/4 for phases.Keywords: Centrifugal compressor, aeroelasticity, interdisciplinary calculation, oscillation phase displacement, vibration, nonstationarity
Procedia PDF Downloads 258