Search results for: two-dimentional mechanical treatments

Authors: Raheb Mirzanamadi, João Patrício

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Asphalt rubber (AR) was initially developed in Sweden in the 1960s by replacing crumb rubber (CR) as aggregates in asphalt pavement. The AR produced by this method had better mechanical properties than conventional asphalt pavement but was very expensive. Since then, different technologies and methods have been developed to use CR in asphalt pavements, including blending CR with bitumen at a high temperature in the mixture, called the wet method, and blending CR with bitumen in the refinery, called the terminal blending method. In 2006, the wet method was imported from the USA to Sweden to evaluate the potential of using AR on Swedish roads. 154 km AR roads were constructed by the wet method in Sweden. The evaluation showed that the AR had, in most cases, better mechanical performance than conventional asphalt pavements. However, the terrible smoke and smell led the Swedish Transport Administration (STA) to stop using AR in Sweden. Today, there are few focuses on AR, despite its good mechanical properties and environmental aspects. Hence, there is a need to study the drives and barriers of using AR mixture in Sweden. The aims of this paper are: (i) to study drivers and barriers of using AR pavements in Sweden and (ii) to discover knowledge gaps for further research in this area. The study was done using a literature review and completed by interviews with experts, including three researchers from Swedish National Road and Transport Research Institute (VTI) and two experts from STA. The results showed that AR can be an alternative not only for conventional asphalt pavement but also for polymer modified asphalt (PMA) due to the same mechanical properties but the lower cost for production. New technologies such as terminal blending and using warm mix asphalt (WMA) methods can lead to reducing the energy and temperature during production processes. From this study, it is found that there is not enough experience and knowledge about AR in Sweden, and more research is needed, including the lifespan of AR, mechanical properties of AR using new technologies, and the impact of AR on spreading and leaching substances into nature. More studies can lead to standardization of using AR in Sweden, a potential solution for the use of end-of-life tyres, with better mechanical properties and lower costs, in comparison with conventional asphalt pavements and PMA.

Keywords: asphalt rubber, crumb rubber, terminal blending method, wet method

Procedia PDF Downloads 82

Authors: Adrian Travieso Disotuar, J. Antonio Travieso Rodriguez, Ramon Jerez Mesa, Montserrat Vilaseca

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The effect of the non-vibration-assisted and vibration-assisted ball burnishing on both the surface and mechanical properties of C300 obtained by Selective Laser Melting additive manufacturing technology is studied in this paper. Different vibration amplitudes preloads, and burnishing strategies were tested. A topographical analysis was performed to determine the surface roughness of the different conditions. Besides, micro tensile tests were carried out in situ on Scanning Electron Microscopy to elucidate the post-treatment effects on damaging mechanisms. Experiments show that vibration-assisted ball burnishing significantly enhances mechanical properties compared to the non-vibration-assisted method. Moreover, it was found that the surface roughness was significantly improved with respect to the reference surface.

Keywords: additive manufacturing, ball burnishing, mechanical properties, metals, surface roughness

Procedia PDF Downloads 80

Authors: Alaeddine Kaouka

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The properties and characterization of Ti-6Al-4V alloys with different contents of Mo were investigated. Microstructure characterization and hardness are considered. The alloy structure was characterized by X-ray diffraction, SEM and optical microscopy. The results showed that the addition of Mo stabilized the β-phase in the treated solution condition. The Mo element added to titanium alloys changes the lattice parameters of phases. Microstructural observations indicate an obvious reduction in the prior grain size. The hardness has increased with the increase in β-phase stability, while Young’s modulus and ductility have decreased.

Keywords: characterization, mechanical properties, molybdenum, titanium alloy

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Authors: Siva Kumar Reddy, Anwesha Mukherjee, Abha Misra

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Excellent energy absorption capability in carbon nanotubes (CNT) is shown in their bulk structure that behaves like super compressible foam. Furthermore, a tunable mechanical behavior of CNT foam is achieved using several methods like changing the concentration of precursors, polymer impregnation, non covalent functionalization of CNT microstructure etc. Influence of magnetic field on compressive behavior of magnetic CNT demonstrated an enhanced peak stress and energy absorption capability, which does not require any surface and structural modification of the foam. This presentation discusses the mechanical behavior of micro porous CNT foam that is impregnated in magnetic field responsive fluid. Magnetic particles are dispersed in a nonmagnetic fluid so that alignment of both particles and CNT could play a crucial role in controlling the stiffness of the overall structure. It is revealed that the compressive behavior of CNT foam critically depends on the fluid viscosity as well as magnetic field intensity. Both peak Stress and energy absorption in CNT foam followed a power law behavior with the increase in the magnetic field intensity. However, in the absence of magnetic field, both peak stress and energy absorption capability of CNT foam presented a linear dependence on the fluid viscosity. Hence, this work demonstrates the role magnetic filed in controlling the mechanical behavior of the foams prepared at nanoscale.

Keywords: carbon nanotubes, magnetic field, energy absorption capability and viscosity

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Authors: Wantanee Polviset, N. Prakobsaeng, N. Wetchakama, C. Yuangklang

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The aim of this study was to evaluate the effect of soybean oil, palm oil and sunflower oil supplementations in total mixed ration on voluntary feed intake, dry matter (DM) digestibility and blood metabolize in crossbred Thai native x American Brahman Cattle. Three Thai native x American Brahman cattle, one-year-old with liveweight of 116±22.59 kg, were randomly assigned according to a 3 x 3 latin square design. Each period of feeding lasted for 21 days to receive three dietary treatments were soybean oil, palm oil and sunflower oil supplementation at 5%. During the experimental periods, all cattle were fed a diet with total mixed ration containing roughage to concentrate ratio of 40:60 and rice straw was used as a roughage source. Based on the present study, the results revealed that voluntary feed intake (kgDM/head/day) and %BW DM intake were not affected (P>0.05), whereas percentage of dry matter digestibility was greater with the soybean oil supplementation (P<0.01). It was also found that blood glucose, blood urea nitrogen, cholesterol, triglyceride, high density lipoprotein and low density lipoprotein in plasma were similar among treatments. Based on this study, supplementing 5% soybean oil in total mixed ration (TMR) diets was suitable in beef cattle without any effect dry matter digestibility and blood metabolites.

Keywords: plant oils, feed intake, blood metabolize, crossbred Thai native x Brahman cattle

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Authors: Luiz C. G. Pennafort Jr., Alexandre de S. Rios, Enio P. de Deus

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In the search for materials that replace conventional polymers in order to preserve natural resources, combined with the need to minimize the problems arising from environmental pollution generated by plastic waste, comes the recycled materials biodegradable, especially the composites reinforced with natural fibers. However, such materials exhibit properties little known, requiring studies of manufacturing methods and characterization of these composites. This article shows informations about preparation and characterization of a composite produced by extrusion, which consists of recycled PVC derived from the recycling of materials discarded, added of the micronized coconut fiber. The recycled PVC with 5% of micronized fiber were characterized by X-ray diffraction, thermogravimetric, differential scanning calorimetry, mechanical analysis and optical microscopy. The use of fiber in the composite caused a decrease in its specific weight, due to the lower specific weight of fibers and the appearance of porosity, in addition to the decrease of mechanical properties.

Keywords: recycled PVC, coconut fiber, characterization, composites

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Authors: Salam Alrekabi, A. B. Cundy, Mohammed Haloob Al-Majidi

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Novel multiscale hybrid reinforced cementitious composites based on carbon nanotubes (MHRCC-CNT), and carbon nanofibers (MHRCC-CNF) are new types of cement-based material fabricated with micro steel fibers and nanofilaments, featuring superior strain hardening, ductility, and energy absorption. This study focused on established models to predict the compressive strength, and direct and splitting tensile strengths of the produced cementitious composites. The analysis was carried out based on the experimental data presented by the previous author’s study, regression analysis, and the established models that available in the literature. The obtained models showed small differences in the predictions and target values with experimental verification indicated that the estimation of the mechanical properties could be achieved with good accuracy.

Keywords: multiscale hybrid reinforced cementitious composites, carbon nanotubes, carbon nanofibers, mechanical strength prediction

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Authors: Siti Aslamyah, Yushinta Fujaya, Okto Rimaldi

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One of the problems faced in the crab hatchery operations is the reliance on the use of natural feed. This study aims to analyze the response of larval development and determine the initial stages crab larvae begin to fully able to accept artificial feeding predigest with the help of probiotic Bacillus sp. The experiment was conducted in June 2014 through July 2014 at the location of the scale backyard hatcheries, Bojo village Mallusettasi sub-district, district Barru. This study was conducted in two stages larval rearing. The first stage is designed in a completely randomized design with 5 treatments and each with 3 repetitions, ie, without the use of artificial feeding; predigest feed given from zoea 1 - megalopa; predigest feed given since zoea 2 - megalopa; predigest feed given from zoea 3 - megalopa; and feed predigest given since zoea 4 - megalopa. The second stage of the two treatments, i.e. comparing artificial feeding without and with predigest. The results showed that the artificial feeding predigest able to replace the use of natural feed started zoea 3 generated based on the survival rate. Artificial feeding predigest provide a higher survival rate (16%) compared to artificial diets without predigest only 10.8%. However, feed predigest not give a different effect on the rate of development of stadia. Cell activity in larvae that received artificial feed predigest higher with RNA-DNA ratio of 8.88 compared with no predigest only 5:36. This research is very valuable information for crab hatchery hatchery scale households have limitations in preparing natural food.

Keywords: artificial feeding, development of stadia, larvae Portunus pelagicus, predigest

Procedia PDF Downloads 533

Authors: Violina R. Angelova, Mariana N. Perifanova-Nemska, Galina P. Uzunova, Krasimir I. Ivanov, Huu Q. Lee

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A field study was conducted to evaluate the efficacy of the sunflower (Helianthus annuus L.) for phytoremediation of contaminated soils. The experiment was performed on an agricultural field contaminated by the Non-Ferrous-Metal Works near Plovdiv, Bulgaria. Field experiments with a randomized, complete block design with five treatments (control, compost amendments added at 20 and 40 t/daa, and vemicompost amendments added at 20 and 40 t/daa) were carried out. The accumulation of heavy metals in the sunflower plant and the quality of the sunflower oil (heavy metals and fatty acid composition) were determined. The tested organic amendments significantly influenced the uptake of Pb, Zn and Cd by the sunflower plant. The incorporation of 40 t/decare of compost and 20 t/decare of vermicompost to the soil led to an increase in the ability of the sunflower to take up and accumulate Cd, Pb and Zn. Sunflower can be subjected to the accumulators of Pb, Zn and Cd and can be successfully used for phytoremediation of contaminated soils with heavy metals. The 40 t/daa compost treatment led to a decrease in heavy metal content in sunflower oil to below the regulated limits. Oil content and fatty acids composition were affected by compost and vermicompost amendment treatments. Adding compost and vermicompost increased the oil content in the seeds. Adding organic amendments increased the content of stearic, palmitoleic and oleic acids, and reduced the content of palmitic and gadoleic acids in sunflower oil. The possibility of further industrial processing of seeds to oil and use of the obtained oil will make sunflowers economically interesting crops for farmers of phytoremediation technology.

Keywords: heavy metals, phytoremediation, polluted soils, sunflower

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Authors: Mahdi Amne Elahi, Marcus Koch, Peter Plapper

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Due to the demand of miniaturizing in automotive industry, the application of laser welding is quite promising. The current study focused on laser micro-welding of CuSn6 bronze and nickel wire for a miniature electromechanical hybrid component. Due to the advantages of laser welding, the welding can be tailored specifically for the requirements of the part. Scanning electron and optical microscopy were implemented to study the microstructure and tensile-shear test was selected to represent the mechanical properties. Different welding sides, beam oscillations, and speeds have been investigated to optimize the tensile-shear load and microstructure. The results show that the mechanical properties and microstructure of the joint is highly under the influence of the mentioned parameters. Due to the lack of intermetallic compounds, the soundness of the joint is achievable by manipulating the geometry of the weld seam and minimize weld defects.

Keywords: bronze, laser micro-welding, microstructure, nickel, tensile shear test

Procedia PDF Downloads 166

Authors: M. Ezkurra, J. A. Esnaola, M. Martinez-Agirre, U. Etxeberria, U. Lertxundi, L. Colomo, M. Begiristain, I. Zurutuza

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Butterfly valves are widely used industrial piping components as on-off and flow controlling devices. The main challenge in the design process of this type of valves is the correct dimensioning to ensure proper mechanical performance as well as to minimise flow losses that affect the efficiency of the system. Butterfly valves are typically dimensioned in a closed position based on mechanical approaches considering uniform hydrostatic pressure, whereas the flow losses are analysed by means of CFD simulations. The main limitation of these approaches is that they do not consider either the influence of the dynamics of the manoeuvring stage or coupled phenomena. Recent works have included the influence of the flow on the mechanical behaviour for different opening angles by means of one-way FSI approach. However, these works consider steady-state flow for the selected angles, not capturing the effect of the transient flow evolution during the manoeuvring stage. Two-way FSI modelling approach could allow overcoming such limitations providing more accurate results. Nevertheless, the use of this technique is limited due to the increase in the computational cost. In the present work, the applicability of FSI one-way and two-way approaches is evaluated for the analysis of butterfly valves, showing that not considering fluid-structure coupling involves not capturing the most critical situation for the valve disc.

Keywords: butterfly valves, fluid-structure interaction, one-way approach, two-way approach

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Authors: Arnab Majumdar, Sanjoy Sadhukhan

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Although gun barrel steels are an important variety from defense view point, available literatures are very limited. In the present work, an IF grade Ni-Cr-Mo-V high strength low alloy steel is produced in Electric Earth Furnace-ESR Route. Ingot was hot forged to desired dimension with a reduction ratio of 70-75% followed by homogenization, hardening and tempering treatment. Sample chemistry, NMIR, macro and micro structural analyses were done. Mechanical properties which include tensile, impact, and fracture toughness were studied. Ultrasonic testing was done to identify internal flaws. The existing high strength low alloy Ni-Cr-Mo-V steel shows improved properties in modified processing route and heat treatment schedule in comparison to properties noted earlier for manufacturing of gun barrels. The improvement in properties seems to withstand higher explosive loads with the same amount of steel in gun barrel application.

Keywords: gun barrel steels, IF grade, chemistry, physical properties, thermal and mechanical processing, mechanical properties, ultrasonic testing

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Authors: Daianne Fernandes Diogenes

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Railway ballast aggregates’ shape properties and size distribution can be directly affected by several factors, such as traffic, fouling, and maintenance processes, which cause breakage and wearing, leading to the fine particles’ accumulation through the ballast layer. This research aims to analyze the influence of traffic, tamping process, and sleepers’ stiffness on aggregates' shape and mechanical properties, by using traditional and digital image processing (DIP) techniques and cyclic tests, like resilient modulus (RM) and permanent deformation (PD). Aggregates were collected in different phases of the railway service life: (i) right after the crushing process; (ii) after construction, for the aggregates positioned below the sleepers and (iii) after 5 years of operation. An increase in the percentage of cubic particles was observed for the materials (ii) and (iii), providing a better interlocking, increasing stiffness and reducing axial deformation after 5 years of service, when compared to the initial conditions.

Keywords: digital image processing, mechanical behavior, railway ballast, shape properties

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Authors: Z. Hormozi Moghaddam, M. Mokhtari-Dizaji, M. Movahedin, M. E. Ravari

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Mechanical index (MI) is used for quantifying acoustic cavitation and the relationship between acoustic pressure and the frequency. In this study, modeling of the MI was applied to provide treatment protocol and to understand the effective physical processes on reproducibility of stem cells. The acoustic pressure and MI equations are modeled and solved to estimate optimal MI for 28, 40, 150 kHz and 1 MHz frequencies. Radial and axial acoustic pressure distribution was extracted. To validate the results of the modeling, the acoustic pressure in the water and near field depth was measured by a piston hydrophone. Results of modeling and experiments show that the model is consistent well to experimental results with 0.91 and 0.90 correlation of coefficient (p<0.05) for 1 MHz and 40 kHz. Low intensity ultrasound with 0.40 MI is more effective on the proliferation rate of the spermatogonial stem cells during the seven days of culture, in contrast, high MI has a harmful effect on the spermatogonial stem cells. This model provides proper treatment planning in vitro and in vivo by estimating the cavitation phenomenon.

Keywords: ultrasound, mechanical index, modeling, stem cell

Procedia PDF Downloads 334

Authors: Anna Perrone, Federico Martinelli

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Olive fruit is well-known for the high content in secondary metabolites with high interest at nutritional, nutraceutical, antioxidant, and healthy levels. The content of secondary metabolites in olive at harvest may be affected by different water regimes, with significant effects on olive oil composition and quality and, consequently, on its healthy and nutritional features. In this work, a summary of several research studies dealing with the biosynthesis of healthy and nutraceutical metabolites of the secondary metabolism in olive fruit will be reported. The phytochemical findings have been correlated with the expression of key genes involved in polyphenol, terpenoid, and carotenoid biosynthesis and metabolism in response to different development stages and water regimes. Flavonoids were highest in immature fruits, while anthocyanins increased at ripening. In epicarp tissue, this was clearly associated with an up-regulation of the UFGT gene. Olive fruits cultivated under different water regimes were analyzed by metabolomics. This method identified several hundred metabolites in the ripe mesocarp. Among them, 46 were differentially accumulated in the comparison between rain-fed and irrigated conditions. Well-known healthy metabolites were more abundant at a higher level of water regimes. Increased content of polyphenols was observed in the rain-fed fruit; particularly, anthocyanin concentration was higher at ripening. Several secondary metabolites were differentially accumulated between different irrigation conditions. These results showed that these metabolic approaches could be efficiently used to determine the effects of agronomic treatments on olive fruit physiology and, consequently, on nutritional and healthy properties of the obtained extra-virgin olive oil.

Keywords: olea europea, anthocyanins, polyphenols, water regimes

Procedia PDF Downloads 149

Authors: Manjot Kaur, Harminder Singh, S. K. Jawandha

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The present investigations were carried out at Fruit Research Farm, Department of Fruit Science, Punjab Agricultural University, Ludhiana during the years 2016 and 2017, with the aim of assessing the effect of amino acids on fruit development, shoot growth and yield of peach. The six-year-old peach trees of cv. Florida Prince were sprayed with 0.25 % and 0.50 % concentrations of amino acids (Peptone P1 023), 7 and 14 days after full bloom and the sprays were repeated after 15 and 30 days. Experimental findings showed that all the amino acid treatments increased fruit growth, shoot growth, fruit retention and yield and decreased fruit drop as compared to control during both the years. Maximum fruit retention (89.29 %) and minimum fruit drop (10.71 %) was observed in T8 (2 sprays @ 0.50%). Highest mean shoot growth (113.89 cm) was recorded in T12 (3 sprays @ 0.50%) while the minimum was in control plants (88.23 cm). Fruit yield was also found to be maximum (53.92 kg/tree) under double spray treatment T8 (2 sprays @ 0.50%) of amino acids and minimum in plants sprayed with triple spray of amino acids. Fruit maturity was advanced by 3-4 days by double spray treatments of amino acids as compared to control. In brief, the application of double spray of amino acids @ 0.50% (applied 14 days after full bloom and 15 days later), was found to be best to improve the fruit growth, fruit retention and yield of Florida Prince peach under Punjab conditions.

Keywords: amino acids, fruit growth, maturity, peach, shoot growth

Procedia PDF Downloads 185

Authors: Bashiru Olayinka Adisa, Najeem Lateef

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The integrated knowledge in the application of mechanical engineering, microprocessor and electronic sensor technologies is becoming the basic skill of a modern engineer in machinery based processes. To meet this objective, we have developed a cross-disciplinary industrial training to teach essential hard technical and soft project skills to the mechanical engineering students in mid-curriculum. Ten groups of students were selected to participate in a 150 hour program. The students were required to design and build a robot with ability to follow tracks and pick/place target blocks in specific locations. The students were trained to integrate the knowledge of computer aid design, electronics, sensor theories and motor technology to fabricate a workable robot as a major outcome of this course. On completion of the project, students competed for top robot honors by demonstrating their robots' movements and performance in pick/place to a panel of judges.

Keywords: electronics, sensor theories and motor, robot, technology

Procedia PDF Downloads 279

Authors: Qing Liu, Jean-fabien Capsal, Claude Richard

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In this current contribution, authors are dedicated to investigate influence of the crystal lamellae orientation on electromechanical behaviors of relaxor ferroelectric Poly (vinylidene fluoride –trifluoroethylene -chlorotrifluoroethylene) (P(VDF-TrFE-CTFE)) films by control of polymer microstructure, aiming to picture the full map of structure-property relationship. In order to define their crystal orientation films, terpolymer films were fabricated by solution-casting, stretching and hot-pressing process. Differential scanning calorimetry, impedance analyzer, and tensile strength techniques were employed to characterize crystallographic parameters, dielectric permittivity, and elastic Young’s modulus respectively. In addition, large electrical induced out-of-plane electrostrictive strain was obtained by cantilever beam mode. Consequently, as-casted pristine films exhibited surprisingly high electrostrictive strain 0.1774% due to considerably small value of elastic Young’s modulus although relatively low dielectric permittivity. Such reasons contributed to large mechanical elastic energy density. Instead, due to 2 folds increase of elastic Young’s modulus and less than 50% augmentation of dielectric constant, fully-crystallized film showed weak electrostrictive behavior and mechanical energy density as well. And subjected to mechanical stretching process, Film C exhibited stronger dielectric constant and out-performed electrostrictive strain over Film B because edge-on crystal lamellae orientation induced by uniaxially mechanical stretch. Hot-press films were compared in term of cooling rate. Rather large electrostrictive strain of 0.2788% for hot-pressed Film D in quenching process was observed although its dielectric permittivity equivalent to that of pristine as-casted Film A, showing highest mechanical elastic energy density value of 359.5 J/m^3. In hot-press cooling process, dielectric permittivity of Film E saw values at 48.8 concomitant with ca.100% increase of Young’s modulus. Films with intermediate mechanical energy density were obtained.

Keywords: crystal orientation, electrostroctive strain, mechanical energy density, permittivity, relaxor ferroelectric

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Authors: Riad Harouz, Brahim Mahfoud

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The threads and the circles on reinforced concrete are obtained by process of hot rolling with pebbles finishers in metal carbide which present a way of rolling around the outside diameter. Our observation is that this throat presents geometrical wear after the end of its cycle determined in tonnage. In our study, we have determined, in a first step, experimentally measurements of the wear in terms of thermo-mechanical parameters (Speed, Load, and Temperature) and the influence of these parameters on the wear. In the second stage, we have developed a mathematical model of lifetime useful for the prognostic of the wear and their changes.

Keywords: lifetime, metal carbides, modeling, thermo-mechanical, wear

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Authors: Reham K. El Sawah, N. S. M. El-Tayeb

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This study aims to produce a polymer matrix composite reinforced with Al₂O₃ nanoparticles in order to enhance the mechanical properties of PMMA. The composite was fabricated via Friction stir processing to ensure homogenous dispersion of Al₂O₃ nanoparticles in the polymer, and the processing was submerged to prevent the sputtering of nanoparticles. The surface quality, microstructure, impact energy and hardness of the prepared samples were investigated. Good surface quality and dispersion of nanoparticles were attained through employing sufficient processing conditions. The experimental results indicated that as the percentage of nanoparticles increased, the impact energy and hardness increased, reaching 2 kJ/m2 and 14.7 HV at a nanoparticle concentration of 25%, which means that the toughness and the hardness of the polymer-ceramic produced composite is higher than unprocessed PMMA by 66% and 33% respectively.

Keywords: friction stir processing, polymer matrix nanocomposite, mechanical properties, microstructure

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Authors: Mir Md. Abdus Salam, Muhammad Mohsin, Pertti Pulkkinen, Paavo Pelkonen, Ari Pappinen

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Soil and water pollution caused by extensive mining practices can adversely affect environmental components, such as humans, animals, and plants. Despite a generally positive contribution to society, mining practices have become a serious threat to biological systems. As metals do not degrade completely, they require immobilization, toxicity reduction, or removal. A greenhouse experiment was conducted to evaluate the effects of lime and N100 (11-amino-1-hydroxyundecylidene) chelate amendment on the growth and phytoextraction potential of the willow variety Klara (S. viminalis × S. schwerinii × S. dasyclados) grown in soils heavily contaminated with copper (Cu). The plants were irrigated with tap or processed water (mine wastewater). The sequential extraction technique and inductively coupled plasma-mass spectrometry (ICP-MS) tool were used to determine the extractable metals and evaluate the fraction of metals in the soil that could be potentially available for plant uptake. The results suggest that the combined effects of the contaminated soil and processed water inhibited growth parameter values. In contrast, the accumulation of Cu in the plant tissues was increased compared to the control. When the soil was supplemented with lime and N100; growth parameter and resistance capacity were significantly higher compared to unamended soil treatments, especially in the contaminated soil treatments. The combined lime- and N100-amended soil treatment produced higher growth rate of biomass, resistance capacity and phytoextraction efficiency levels relative to either the lime-amended or the N100-amended soil treatments. This study provides practical evidence of the efficient chelate-assisted phytoextraction capability of Klara and highlights its potential as a viable and inexpensive novel approach for in-situ remediation of Cu-contaminated soils and mine wastewaters. Abandoned agricultural, industrial and mining sites can also be utilized by a Salix afforestation program without conflict with the production of food crops. This kind of program may create opportunities for bioenergy production and economic development, but contamination levels should be examined before bioenergy products are used.

Keywords: copper, Klara, lime, N100, phytoextraction

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Authors: Sudik S. D., Raymon J. B., Maidala A., Lawan A., Bagudu I. A.

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An experiment was conducted with 240 Abor Acre broilers to determine the effect of replacing maize with acha offal (Digitaria exilis) on performance, haematology, and serum biochemical. Chicks were allotted to six diets (T1, T2, T3, T4, T5, and T6) with acha offal (AO) at 0.0%, 5.0%, 7.5%, 10.0%, 12.5% and 15.0% respectively as replacement of maize with 4 replicates consisting of 10 birds per replicate in a completely randomized design. They were allowed ad libitum accessed to feed and water throughout a 42 days experiment. The results showed that at the starter phase, only feed conversion ratio (FCR) was significantly affected (p < 0.05). Chicks fed T5 had best FCR more than those fed T1 while those fed T2, T3, T4, and T6 had similar FCR comparable with T1. At the finisher stage, final weight (FW), total weight change (TWC), average daily gain (ADG), and FCR were significantly affected (p < 0.05). Chickens fed T3, T4, T5, and T6 had similar FW, TWC, and ADG and higher than those fed T1; those fed T2 had similar FW, TWG, and DWG with T1. Chickens fed T6 had best FCR, followed by those fed T3, T4, and T5, while those T2 had worse FCR similar with those fed T1. Eviscerated weight was significantly affected (p < 0.05) by treatment. Birds fed T4, T5, and T6 had higher eviscerated weight followed by T3 while those fed T2 had least eviscerated weight comparable with those fed T1. The entire organs (Gizzard, heart, kidneys, liver, lungs, pancreas, and proventriculus) were not significantly affected (p > 0.05) by treatments. Packed cell volume (PCV) and red blood cell (RBC) were significantly (p < 0.05) affected by treatment. Birds fed T4, T5, and T6 had higher and similar PCV and RBC with those fed T1 while those fed T2 and T3 had lower PCV and RBC. The entire serum metabolites were not significantly affected (p > 0.05) by treatments. In conclusion, acha offal can replace maize in starter and finisher broilers’ diets at 12.5% and 15.0%, respectively, without an adverse effect.

Keywords: broiler, acha offal, maize, performance, eviscerated, haematology, serum

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Authors: Nasruddin Junus

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CFTR column is one of the improvements CFT columns by inserting reinforcing steel bars into infill concrete. The presence of inserting reinforcing steel bars is increasing the excellent structural performance of the CFT column, especially on the fire-resisting performance. Investigation on the mechanical behavior of CFTR column connection is summarized in the three parts; column to column joint, column to beam connection, and column base. Experiment that reported in this paper is concerned on the mechanical behavior of CFTR column joint under pull out testing, especially on its stress transfer mechanism. A number series of the pull out test on the CFT with inserting reinforcing steel bar are conducted. Ten test specimens are designed, constructed, and tested to examine experimentally the effect of the size of square steel tube, size of the bearing plate, length of embedment steel bars, kind of steel bars, and the numbers of rib plate.

Keywords: CFTR column, pull out, stress, transfer mechanism

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Authors: Mahmoudi Noureddine

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In this study the use of two variable refined plate theories of laminated composite plates to static response of laminated plates. The plate theory accounts for parabolic distribution of the transverse shear strains, and satisfies the zero traction boundary conditions on the surfaces of the plate without using shear correction factor. The validity of the present theory is demonstrated by comparison with solutions available in the literature and finite element method. The result is presented for the static response of simply supported rectangular plates under uniform sinusoidal mechanical loadings.

Keywords: bending, composite, laminate, plates, fem

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Authors: Timo Avikainen, Tuukka Verho

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The use of natural fibers as reinforcements is growing increasingly in polymers which are involved in e.g. structural, vibration, and acoustic applications. The use of bio composites is being investigated as lightweight materials with specific properties like the ability to dissipate vibration energy and positive environmental profile and are thus considered as potential replacements for synthetic composites. The macro-level mechanical properties of the biocomposite material depend on several parameters in the detailed architecture and morphology of the reinforcing fiber structure. The polymer matrix phase is often applied to remain the fiber structure in touch. A big role in the packaging details of the fibers is related to the used manufacturing processes like extrusion, injection molding and treatments. There are typically big variances in the detailed parameters of the microstructure fibers. The study addressed the question of how the multiscale simulation methodology works in bio composites with short pulp fibers. The target is to see how the vibro – acoustic performance of thin–walled panels can be controlled by the detailed characteristics of the fiber material. Panels can be used in sound-producing speakers or sound insulation applications. The multiscale analysis chain is tested starting from the microstructural level and continuing via macrostructural material parameters to the product component part/assembly levels. Another application is the dynamic impact type of loading, exposing the material to the crack type damages that is in this study modeled as the Charpy impact tests.

Keywords: bio composite, pulp fiber, vibration, acoustics, impact, FEM

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Authors: Nikolaos Reppas, Yilin Gui

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A dual-porosity finite element-code will be presented for the stability analysis of the wellbore during CO₂ injection. An elastoplastic damage response will be considered to the model. The Finite Element Method (FEM) will be validated using experimental results from literature or from experiments that are planned to be undertaken at Newcastle University. The main target of the research paper is to present a constitutive model that can help industries to safely store CO₂ in geological rock formations and forecast any changes on the surrounding rock of the wellbore. The fully coupled elastoplastic damage Thermo-Hydraulic-Mechanical (THM) model will determine the pressure and temperature of the injected CO₂ as well as the size of the radius of the wellbore that can make the Carbon Capture and Storage (CCS) procedure more efficient.

Keywords: carbon capture and storage, Wellbore stability, elastoplastic damage response for rock, constitutive THM model, fully coupled thermo-hydraulic-mechanical model

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Authors: B. J. Babalola, M. B. Shongwe

Abstract:

Spark Plasma Sintering technique is a novel processing method that produces limited grain growth and highly dense variety of materials; alloys, superalloys, and carbides just to mention a few. However, initial particle size and spark plasma sintering parameters are factors which influence the grain growth and mechanical properties of sintered materials. Ni-Cr alloys are regarded as the most promising alloys for aerospace turbine blades, owing to the fact that they meet the basic requirements of desirable mechanical strength at high temperatures and good resistance to oxidation. The conventional method of producing this alloy often results in excessive grain growth and porosity levels that are detrimental to its mechanical properties. The effect of sintering temperature was evaluated on the microstructure and mechanical properties of the nanostructured Ni-17Cr alloy. Nickel and chromium powder were milled using high energy ball milling independently for 30 hours, milling speed of 400 revs/min and ball to powder ratio (BPR) of 10:1. The milled powders were mixed in the composition of Nickel having 83 wt % and chromium, 17 wt %. This was sintered at varied temperatures from 800°C, 900°C, 1000°C, 1100°C and 1200°C. The structural characteristics such as porosity, grain size, fracture surface and hardness were analyzed by scan electron microscopy and X-ray diffraction, Archimedes densitometry, micro-hardness tester. The corresponding results indicated an increase in the densification and hardness property of the alloy as the temperature increases. The residual porosity of the alloy reduces with respect to the sintering temperature and in contrast, the grain size was enhanced. The study of the mechanical properties, including hardness, densification shows that optimum properties were obtained for the sintering temperature of 1100°C. The advantages of high sinterability of Ni-17Cr alloy using milled powders and microstructural details were discussed.

Keywords: densification, grain growth, milling, nanostructured materials, sintering temperature

Procedia PDF Downloads 402

Authors: V. Viliene, A. Raceviciute-Stupeliene, V. Sasyte, V. Slausgalvis, R. Gruzauskas, J. Al-Saifi

Abstract:

Animal nutritionists and scientists have searched for alternative measures to improve the production. One of such alternative is use of organic acids as feed additive in animal nutrition. The study was conducted to investigate the impact of butyric acids, calcium formate, organic acids, and its salts (BCOS) additives on rabbit’s productive performance, carcass traits and meat quality. The study was conducted with 14 Californian breed rabbits. The rabbits were assigned to two treatment groups (seven rabbits per each treatment group). The dietary treatments were 1) control diet, 2) diet supplemented with a mixture BCOS - 2 kg/t of feed. Growth performance characteristics (body weight, daily weight gain, daily feed intake, feed conversion ratio, mortality) were evaluated. Rabbits were slaughtered; carcass characteristics and meat quality were evaluated. Samples loin and hind leg meat were analysed to determine carcass characteristics, pH and colour measurements, cholesterol, and malonyldialdehyde (MDA) content in loin and hind leg meat. Differences between treatments were significant for body weight (1.30 vs. 1.36 kg; P<0.05), daily weight gain (16.60 vs. 17.85 g; P<0.05), and daily feed intake (78.25 vs. 80.58 g; P<0.05) for control and experimental group respectively for the entire experimental period (from 28–77 days old). No significant differences were found in feed conversion ratio and mortality. The feed additives insertion in the diets did not significantly influence the carcass yield or the proportions of the various carcass parts and organs. Differences between treatments were significant for pH value after 48h in loin (5.86 vs. 5.74; P<0.05), hind leg meat (6.62 vs. 6.65; P<0.05), more intense colour b* of loin (5.57 vs. 6.06; P<0.05), less intense colour a* (14.99 vs. 13.15; P<0.05) in hind leg meat. Cholesterol content in hind leg meat decreased by 17.67 mg/100g compared to control group (P<0.05). After storage for three months, MDA concentration decreased in loin and hind leg meat by 0.3 μmol/kg and 0.26 μmol/kg respectively compared to that of the control group (P<0.05). The results of this study suggest that BCOS could potentially be used in rabbit nutrition with consequent benefits on the rabbits’ productivity and nutritional quality of rabbit meat for consumers.

Keywords: butyric acids, Ca formate, meat quality, organic acids salts, rabbits, productivity

Procedia PDF Downloads 215

Authors: Mia I. Allen, Bernard N. Johnson, Gagan Deep, Yixin Su, Sangeeta Singth, Ashish Kumar, , Michael A. Nader

Abstract:

With no FDA-approved treatments for cocaine use disorders (CUD), research has focused on the behavioral and neuropharmacological effects of cocaine in animal models, with the goal of identifying novel interventions. While the majority of people with CUD also use tobacco/nicotine, the majority of preclinical cocaine research does not include the co-use of nicotine. The present study examined nicotine and cocaine co-use under several conditions of intravenous drug self-administration in monkeys. In Experiment 1, male rhesus monkeys (N=3) self-administered cocaine (0.001-0.1 mg/kg/injection) alone and cocaine+nicotine (0.01-0.03 mg/kg/injection) under a progressive-ratio schedule of reinforcement. When nicotine was added to cocaine, there was a significant leftward shift and significant increase in peak break point. In Experiment 2, socially housed female and male cynomolgus monkeys (N=14) self-administered cocaine under a concurrent drug-vs-food choice schedule. Combining nicotine significantly decreased cocaine choice ED50 values (i.e., shifted the cocaine dose-response curve to the left) in females but not in males. There was no evidence of social rank differences. In delay discounting studies, the co-use of nicotine and cocaine required significantly larger delays to the preferred drug reinforcer to reallocate choice compared with cocaine alone. Overall, these results suggest drug interactions of nicotine and cocaine co-use is not simply a function of potency but rather a fundamentally distinctive condition that should be utilized to better understand the neuropharmacology of CUD and the evaluation of potential treatments.

Keywords: polydrug use, animal models, nonhuman primates, behavioral pharmacology, drug self-administration

Procedia PDF Downloads 87

Authors: Sana Ridene, Soumaya Sayeb, Houda Helali, Mohammed Ben Hassen

Abstract:

Nonwoven structures have a range of applications which include Medical, filtration, geotextile and recently this unconventional fabric is finding a niche in fashion apparel. In this paper, a modified form of Vangheluwe rheological model is used to describe the mechanical behavior of nonwovens fabrics in uniaxial tension. This model is an association in parallel of three Maxwell elements characterized by damping coefficients η1, η2 and η3 and E1, E2, E3 elastic modulus and a nonlinear spring C. The model is verified experimentally with two types of nonwovens (50% viscose /50% Polyester) and (40% viscose/60% Polyester) and a range of three square weights values. Comparative analysis of the theoretical model and the experimental results of tensile test proofs a high correlation between them. The proposed model can fairly well replicate the behavior of nonwoven fabrics during relaxation and sample traction. This allowed us to predict the mechanical behavior in tension and relaxation of fabrics starting only from their technical parameters (composition and weight).

Keywords: mechanical behavior, tensile strength, relaxation, rheological model

Procedia PDF Downloads 409