Search results for: sound absorption material
3446 Functionally Graded MEMS Piezoelectric Energy Harvester with Magnetic Tip Mass
Authors: M. Derayatifar, M. Packirisamy, R.B. Bhat
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Role of piezoelectric energy harvesters has gained interest in supplying power for micro devices such as health monitoring sensors. In this study, in order to enhance the piezoelectric energy harvesting in capturing energy from broader range of excitation and to improve the mechanical and electrical responses, bimorph piezoelectric energy harvester beam with magnetic mass attached at the end is presented. In view of overcoming the brittleness of piezo-ceramics, functionally graded piezoelectric layers comprising of both piezo-ceramic and piezo-polymer is employed. The nonlinear equations of motions are derived using energy method and then solved analytically using perturbation scheme. The frequency responses of the forced vibration case are obtained for the near resonance case. The nonlinear dynamic responses of the MEMS scaled functionally graded piezoelectric energy harvester in this paper may be utilized in different design scenarios to increase the efficiency of the harvester.Keywords: energy harvesting, functionally graded piezoelectric material, magnetic force, MEMS (micro-electro-mechanical systems) piezoelectric, perturbation method
Procedia PDF Downloads 1963445 Cellulose Nanocrystals Suspensions as Water-Based Lubricants for Slurry Pump Gland Seals
Authors: Mohammad Javad Shariatzadeh, Dana Grecov
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The tribological tests were performed on a new tribometer, in order to measure the coefficient of friction of a gland seal packing material on stainless steel shafts in presence of Cellulose Nanocrystal (CNC) suspension as a sustainable, environmentally friendly, water-based lubricant. To simulate the real situation from the slurry pumps, silica sands were used as slurry particles. The surface profiles after tests were measured by interferometer microscope to characterize the surface wear. Moreover, the coefficient of friction and surface wear were measured between stainless steel shaft and chrome steel ball to investigate the tribological effects of CNC in boundary lubrication region. Alignment of nanoparticles in the CNC suspensions are the main reason for friction and wear reduction. The homogeneous concentrated suspensions showed fingerprint patterns of a chiral nematic liquid crystal. These properties made CNC a very good lubricant additive in water.Keywords: gland seal, lubricant additives, nanocrystalline cellulose, water-based lubricants
Procedia PDF Downloads 1873444 Piezoelectric Actuator for Controlling Robotics Organs
Authors: Lemoussi Somia, Ouali Mohammed, Zemirline Adel
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In precision engineering, including precision positioning, micro-manipulation, robotic systems... a majority of these applications actuated by piezo stack used the compliant amplifier mechanism to amplifying motion and guiding it as needed utilize the flexibility of their components, in this paper, we present a novel approach introducing a symmetric structure comprising three stages, featuring rectangular flexure hinges with a compact size of 77mm×42mm×10mm. This design provides the capability for rotation, translation or a combination of both movements in both directions. The system allows for a displacement of 2107.5 μm when the input displacement of PZT is 50 μm while considering the material constraints of the aluminum alloy (7075 T6) which has a maximum admissible stress of 500 MPa However, our proposed design imposes additional constraints to ensure the stress remains below 361 MPa for optimal performance. These findings were obtained through finite element simulations conducted using ANSYS Workbench. Furthermore, our module facilitates precise control of various components within robotic systems, allowing for adjustable speeds based on specific requirements or desired outcomes.Keywords: robotic, piezoelectric, compliant mechanism, flexure hinge
Procedia PDF Downloads 833443 High Temperature Oxidation of Cr-Steel Interconnects in Solid Oxide Fuel Cells
Authors: Saeed Ghali, Azza Ahmed, Taha Mattar
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Solid Oxide Fuel Cell (SOFC) is a promising solution for the energy resources leakage. Ferritic stainless steel becomes a suitable candidate for the SOFCs interconnects due to the recent advancements. Different steel alloys were designed to satisfy the needed characteristics in SOFCs interconnect as conductivity, thermal expansion and corrosion resistance. Refractory elements were used as alloying elements to satisfy the needed properties. The oxidation behaviour of the developed alloys was studied where the samples were heated for long time period at the maximum operating temperature to simulate the real working conditions. The formed scale and oxidized surface were investigated by SEM. Microstructure examination was carried out for some selected steel grades. The effect of alloying elements on the behaviour of the proposed interconnects material and the performance during the working conditions of the cells are explored and discussed. Refractory metals alloying of chromium steel seems to satisfy the needed characteristics in metallic interconnects.Keywords: SOFCs, Cr-steel, interconnects, oxidation
Procedia PDF Downloads 3343442 Failure Cases Analysis in Petrochemical Industry
Authors: S. W. Liu, J. H. Lv, W. Z. Wang
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In recent years, the failure accidents in petrochemical industry have been frequent, and have posed great security problems in personnel and property. The improvement of petrochemical safety is highly requested in order to prevent re-occurrence of severe accident. This study focuses on surveying the failure cases occurred in petrochemical field, which were extracted from journals of engineering failure, including engineering failure analysis and case studies in engineering failure analysis. The relation of failure mode, failure mechanism, type of components, and type of materials was analyzed in this study. And the analytical results showed that failures occurred more frequently in vessels and piping among the petrochemical equipment. Moreover, equipment made of carbon steel and stainless steel accounts for the majority of failures compared to other materials. This may be related to the application of the equipment and the performance of the material. In addition, corrosion failures were the largest in number of occurrence in the failure of petrochemical equipment, in which stress corrosion cracking accounts for a large proportion. This may have a lot to do with the service environment of the petrochemical equipment. Therefore, it can be concluded that the corrosion prevention of petrochemical equipment is particularly important.Keywords: cases analysis, corrosion, failure, petrochemical industry
Procedia PDF Downloads 3103441 Analyzing the Readiness of Resuscitation Team during Cardiac Arrest
Authors: J. Byimana, I. A. Muhire, J. E. Nzabahimana, A. Nyombayire
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Introduction: A successful cardiopulmonary resuscitation during a sudden cardiac arrest can be delayed by different components including new hospital setting, lack of adequate training, lack of pre-established resuscitation team and ineffective communication and lead to an unexpected outcome which is death. The main objective of the study was to assess the readiness of resuscitation teams during cardiac arrest and the organizational approaches that would best support their functioning in a new hospital facility, and to detect any factor that may have contributed to responses. This study analyses the readiness of Resuscitation Team (RT) during cardiac arrest. —Material and methods: A prospective Analytic design was carried out at a newly established United Nations level 2 hospital facility, on four RTM (resuscitation team member). A semi structured questionnaire was used to collect data. —Results: This study highlights indicate that the response time during cardiac arrest simulation meet both American heart association (AHA) and European resuscitation council guidelines. The study offers useful evidence about the impact of a new facility on RTM performance and provides an exposure of staff to emergency events within the Work setting.Keywords: cardiac arrest, code blue, simulation, resuscitation team member
Procedia PDF Downloads 2273440 The Real Ambassador: How Hip Hop Culture Connects and Educates across Borders
Authors: Frederick Gooding
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This paper explores how many Hip Hop artists have intentionally and strategically invoked sustainability principles of people, planet and profits as a means to create community, compensate for and cope with structural inequalities in society. These themes not only create community within one's country, but the powerful display and demonstration of these narratives create community on a global plane. Listeners of Hip Hop are therefore able to learn about the political events occurring in another country free of censure, and establish solidarity worldwide. Hip Hop therefore can be an ingenious tool to create self-worth, recycle positive imagery, and serve as a defense mechanism from institutional and structural forces that conspire to make an upward economic and social trajectory difficult, if not impossible for many people of color, all across the world. Although the birthplace of Hip Hop, the United States of America, is still predominately White, it has undoubtedly grown more diverse at a breath-taking pace in recent decades. Yet, whether American mainstream media will fully reflect America’s newfound diversity remains to be seen. As it stands, American mainstream media is seen and enjoyed by diverse audiences not just in America, but all over the world. Thus, it is imperative that further inquiry is conducted about one of the fastest growing genres within one of the world’s largest and most influential media industries generating upwards of $10 billion annually. More importantly, hip hop, its music and associated culture collectively represent a shared social experience of significant value. They are important tools used both to inform and influence economic, social and political identity. Conversely, principles of American exceptionalism often prioritize American political issues over those of others, thereby rendering a myopic political view within the mainstream. This paper will therefore engage in an international contextualization of the global phenomena entitled Hip Hop by exploring the creative genius and marketing appeal of Hip Hop within the global context of information technology, political expression and social change in addition to taking a critical look at historically racialized imagery within mainstream media. Many artists the world over have been able to freely express themselves and connect with broader communities outside of their own borders, all through the sound practice of the craft of Hip Hop. An empirical understanding of political, social and economic forces within the United States will serve as a bridge for identifying and analyzing transnational themes of commonality for typically marginalized or disaffected communities facing similar struggles for survival and respect. The sharing of commonalities of marginalized cultures not only serves as a source of education outside of typically myopic, mainstream sources, but it also creates transnational bonds globally to the extent that practicing artists resonate with many of the original themes of (now mostly underground) Hip Hop as with many of the African American artists responsible for creating and fostering Hip Hop's powerful outlet of expression. Hip Hop's power of connectivity and culture-sharing transnationally across borders provides a key source of education to be taken seriously by academics.Keywords: culture, education, global, hip hop, mainstream music, transnational
Procedia PDF Downloads 1073439 Exploring the Biocompatibility and Performance of Metals and Ceramics as Biomaterials, A Comprehensive Study for Advanced Medical Applications
Authors: Ala Abobakr Abdulhafidh Al-Dubai
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Biomaterials, specifically metals and ceramics, are indispensable components in the realm of medical science, shaping the landscape of implantology and prosthetics. This study delves into the intricate interplay between these materials and biological systems, aiming to scrutinize their suitability, performance, and biocompatibility. Employing a multi-faceted approach, a range of methodologies were meticulously employed to comprehensively characterize these biomaterials. Advanced material characterization techniques were paramount in this research, with scanning electron microscopy providing intricate insights into surface morphology, and X-ray diffraction unraveling the crystalline structures. These analyses were complemented by in vitro assessments, which gauged the biological response of cells to metals and ceramics, shedding light on their potential applications within the human body. A key facet of our investigation involved a comparative study, evaluating the corrosion resistance and osseointegration potential of both metals and ceramics. Through a series of experiments, we sought to understand how these biomaterials interacted with physiological environments, paving the way for informed decisions in medical applicationsKeywords: metals, ceramics, biomaterials, biocompatibility, osseointegration
Procedia PDF Downloads 723438 Formation of Science Literations Based on Indigenous Science Mbaru Niang Manggarai
Authors: Yuliana Wahyu, Ambros Leonangung Edu
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The learning praxis that is proposed by 2013 Curriculum (K-13) is no longer school-oriented as a supply-driven, but now a demand-driven provider. This vision is connected with Jokowi-Kalla Nawacita program to create a competitive nation in the global era. Competition is a social fact that must be faced. Therefore the curriculum will design a process to be the innovators and entrepreneurs.To get this goal, K-13 implements the character education. This aims at creating the innovators and entrepreneurs from an early age (primary school). One part of strengthening it is literacy formations (reading, numeracy, science, ICT, finance, and culture). Thus, science literacy is an integral part of character education. The above outputs are only formed through the innovative process through intra-curricular (blended learning), co-curriculer (hands-on learning) and extra-curricular (personalized learning). Unlike the curriculums before that child cram with the theories dominating the intellectual process, new breakthroughs make natural, social, and cultural phenomena as learning sources. For example, Science in primary schoolsplaceBiology as the platform. And Science places natural, social, and cultural phenomena as a learning field so that students can learn, discover, solve concrete problems, and the prospects of development and application in their everyday lives. Science education not only learns about facts collection or natural phenomena but also methods and scientific attitudes. In turn, Science will form the science literacy. Science literacy have critical, creative, logical, and initiative competences in responding to the issues of culture, science and technology. This is linked with science nature which includes hands-on and minds-on. To sustain the effectiveness of science learning, K-13 opens a new way of viewing a contextual learning model in which facts or natural phenomena are drawn closer to the child's learning environment to be studied and analyzed scientifically. Thus, the topic of elementary science discussion is the practical and contextual things that students encounter. This research is about to contextualize Science in primary schools at Manggarai, NTT, by placing local wisdom as a learning source and media to form the science literacy. Explicitly, this study discovers the concept of science and mathematics in Mbaru Niang. Mbaru Niang is a forgotten potentials of the centralistic-theoretical mainstream curriculum so far. In fact, the traditional Manggarai community stores and inherits much of the science-mathematical indigenous sciences. In the traditional house structures are full of science and mathematics knowledge. Every details have style, sound and mathematical symbols. Learning this, students are able to collaborate and synergize the content and learning resources in student learning activities. This is constructivist contextual learning that will be applied in meaningful learning. Meaningful learning allows students to learn by doing. Students then connect topics to the context, and science literacy is constructed from their factual experiences. The research location will be conducted in Manggarai through observation, interview, and literature study.Keywords: indigenous science, Mbaru Niang, science literacy, science
Procedia PDF Downloads 2113437 Combination Urea and KCl with Powder Coal Sub-Bituminous to Increase Nutrient Content of Ultisols in Limau Manis Padang West Sumatra
Authors: Amsar Maulana, Rafdea Syafitri, Topanal Gustiranda, Natasya Permatasari, Herviyanti
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Coal as an alternative source of humic material that has the potential of 973.92 million tons (sub-bituminous amounted to 673.70 million tons) in West Sumatera. The purpose of this research was to study combination Urea and KCl with powder coal Sub-bituminous to increase nutrient content of Ultisols In Limau Manis Padang West Sumatera. The experiment was designed in Completely Randomized Design with 3 replications, those were T1) 0.5% (50g plot-1) of powder coal Sub-bituminous; T2) T1 and 125% (7.03g plot-1 ) of Urea recommendation; T3) T1 and 125% (5.85g plot-1) of KCl recommendation; T4) 1.0% (100g plot-1) of powder coal Sub-bituminous; T5) T4 and 125% (7.03g plot-1 ) of Urea recommendation; T6) T4 and 125% (5.85g plot-1) of KCl recommendation; T7) 1.5% (150g plot-1) of powder coal Sub-bituminous; T8) T7 and 125% (7.03g plot-1 ) of Urea recommendation; T9) T7 and 125% (5.85g plot-1) of KCl recommendation. The results showed that application 1.5% of powder coal Sub-bituminous and 125% of Urea recommendation could increase nutrient content of Ultisols such as pH by 0.33 unit, Organic – C by 2.03%, total – N by 0.31%, Available P by 14.16 ppm and CEC by 19.38 me 100g-1 after 2 weeks of incubation process.Keywords: KCl, sub-bituminous, ultisols, urea
Procedia PDF Downloads 2673436 Bio-Hub Ecosystems: Expansion of Traditional Life Cycle Analysis Metrics to Include Zero-Waste Circularity Measures
Authors: Kimberly Samaha
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In order to attract new types of investors into the emerging Bio-Economy, a new set of metrics and measurement system is needed to better quantify the environmental, social and economic impacts of circular zero-waste design. The Bio-Hub Ecosystem model was developed to address a critical area of concern within the global energy market regarding the use of biomass as a feedstock for power plants. Lack of an economically-viable business model for bioenergy facilities has resulted in the continuation of idled and decommissioned plants. In particular, the forestry-based plants which have been an invaluable outlet for woody biomass surplus, forest health improvement, timber production enhancement, and especially reduction of wildfire risk. This study looked at repurposing existing biomass-energy plants into Circular Zero-Waste Bio-Hub Ecosystems. A Bio-Hub model that first targets a ‘whole-tree’ approach and then looks at the circular economics of co-hosting diverse industries (wood processing, aquaculture, agriculture) in the vicinity of the Biomass Power Plants facilities. It proposes not only models for integration of forestry, aquaculture, and agriculture in cradle-to-cradle linkages of what have typically been linear systems, but the proposal also allows for the early measurement of the circularity and impact of resource use and investment risk mitigation, for these systems. Typically, life cycle analyses measure environmental impacts of different industrial production stages and are not integrated with indicators of material use circularity. This concept paper proposes the further development of a new set of metrics that would illustrate not only the typical life-cycle analysis (LCA), which shows the reduction in greenhouse gas (GHG) emissions, but also the zero-waste circularity measures of mass balance of the full value chain of the raw material and energy content/caloric value. These new measures quantify key impacts in making hyper-efficient use of natural resources and eliminating waste to landfills. The project utilized traditional LCA using the GREET model where the standalone biomass energy plant case was contrasted with the integration of a jet-fuel biorefinery. The methodology was then expanded to include combinations of co-hosts that optimize the life cycle of woody biomass from tree to energy, CO₂, heat and wood ash both from an energy/caloric value and for mass balance to include reuse of waste streams which are typically landfilled. The major findings of both a formal LCA study resulted in the masterplan for the first Bio-Hub to be built in West Enfield, Maine. Bioenergy facilities are currently at a critical juncture where they have an opportunity to be repurposed into efficient, profitable and socially responsible investments, or be idled and scrapped. If proven as a model, the expedited roll-out of these innovative scenarios can set a new standard for circular zero-waste projects that advance the critical transition from the current ‘take-make-dispose’ paradigm inherent in the energy, forestry and food industries to a more sustainable bio-economy paradigm where waste streams become valuable inputs, supporting local and rural communities in simple, sustainable ways.Keywords: bio-economy, biomass energy, financing, metrics
Procedia PDF Downloads 1623435 Establishment of Standardized Bill of Material for Korean Urban Rail Transit System
Authors: J. E. Jung, J. M. Yang, J. W. Kim
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The railway market across the world has been standardized with the globalization strategy of Europe. On the other hand, the Korean urban railway system is operated by 10 operators which have established their standards and independently managed BOMs. When operators manage different BOMs, lack of system compatibility prevents them from sharing information and hinders work linkage and efficiency. Europe launched a large-scale railway project in 1993 when the European Union went into effect. In particular, the recent standardization efforts of the EU-funded MODTRAIN project are similar to the approach of the urban rail system standardization research that is underway in Korea. This paper looks into the BOMs of Koran urban rail transit operators and suggests the standard BOM for the rail transit system in Korea by reviewing rail vehicle technologies and the MODTRAIN project of Europe. The standard BOM is structured up to the key device level or module level, and it allows vehicle manufacturers and component manufacturers to manage their lower-level BOMs and share them with each other and with operators.Keywords: BOM, Korean rail, urban rail, standardized
Procedia PDF Downloads 3153434 Temperature Control and Thermal Management of Cylindrical Lithium Batteries Using Phase Change Materials (PCMs)
Authors: S. M. Sadrameli, Y. Azizi
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Lithium-ion batteries (LIBs) have shown to be one of the most reliable energy storage systems for electric cars in the recent years. Ambient temperature has a significant impact on the performance, lifetime, safety and cost of such batteries. Increasing the temperature degrade the lithium batteries more quickly while working at low-temperature environment results reducing the power and energy capability of the system. A thermal management system has been designed and setup in laboratory scale for controlling the temperature at optimum conditions using PEG-1000 with the melting point in the range of 33-40 oC as a phase change material. Aluminum plates have been installed in the PCM to increase the thermal conductivity and increasing the heat transfer rate. Experimental tests have been run at different discharge rates and ambient temperatures to investigate the effects of temperature on the efficiency of the batteries. The comparison has been made between the system of 6 batteries with and without PCM and the results show that PCM with aluminum plates decrease the surface temperature of the batteries that would result better performance and longer lifetime of the batteries.Keywords: lithium-ion batteries, phase change materials, thermal management, temperature control
Procedia PDF Downloads 3453433 Testing of Small Local Zones by Means of Small Punch Test at Room and Creep Temperatures
Authors: Vaclav Mentl, Josef Volak
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In many industrial applications, materials are subjected to degradation of mechanical properties as a result of real service conditions, temperature, cyclic loading, humidity or other corrosive media, irradiation, their combination etc. The assessment of the remaining lifetime of components and structures is commonly based on correlated procedures including numerous destructive, non-destructive and mathematical techniques that should guarantee reasonably precise assessment of the current damage extent of materials in question and the remaining lifetime evaluation of the component under consideration. The answers to demands of customers to extend the lifetime of existing components beyond their original design life must be based on detailed assessment of the current degradation extent, what can be rarely realised by means of traditional mechanical (standardised) tests that need relatively large volumes of representative material for the test specimen manufacturing. This fact accelerated the research of miniaturised test specimen that can be sampled non-invasively from the component.Keywords: small punch test, correlation, creep, mechanical properties
Procedia PDF Downloads 2783432 On-Farm Mechanized Conservation Agriculture: Preliminary Agro-Economic Performance Difference between Disc Harrowing, Ripping and No-Till
Authors: Godfrey Omulo, Regina Birner, Karlheinz Koller, Thomas Daum
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Conservation agriculture (CA) as a climate-resilient and sustainable practice have been carried out for over three decades in Zambia. However, its continued promotion and adoption has been predominantly on a small-scale basis. Despite the plethora of scholarship pointing to the positive benefits of CA in regard to enhanced yield, profitability, carbon sequestration and minimal environmental degradation, these have not stimulated commensurate agricultural extensification desired for Zambia. The objective of this study was to investigate the potential differences between mechanized conventional and conservation tillage practices on operation time, fuel consumption, labor costs, soil moisture retention, soil temperature and crop yield. An on-farm mechanized conservation agriculture (MCA) experiment arranged in a randomized complete block design with four replications was used. The research was conducted on a 15 ha of sandy loam rainfed land: soybeans on 7ha with plot dimensions of 24 m by 210 m and maize on 8ha with plot dimensions of 24 m by 250 m. The three tillage treatments were: residue burning followed by disc harrowing, ripping tillage and no-till. The crops were rotated in two subsequent seasons. All operations were done using a 60hp 2-wheel tractor, a disc harrow, a two-tine ripper and a two-row planter. Soil measurements and the agro-economic factors were recorded for two farming seasons. The season results showed that the yield of maize and soybeans under no-till and ripping tillage practices were not significantly different from the conventional burning and discing. But, there was a significant difference in soil moisture content between no-till (25.31SFU±2.77) and disced (11.91SFU±0.59) plots at depths from 10-60 cm. Soil temperature in no-till plots (24.59°C±0.91) was significantly lower compared to the disced plots (26.20°C±1.75) at the depths 15 cm and 45 cm. For maize, there was a significant difference in operation time between disc-harrowed (3.68hr/ha±1.27) and no-till (1.85hr/ha±0.04) plots, and a significant difference in cost of labor between disc-harrowed (45.45$/ha±19.56) and no-till (21.76$/ha) plots. There was no significant difference in fuel consumption between ripping and disc-harrowing and direct seeding. For soybeans, there was a significant difference in operation time between no-tillage (1.96hr/ha±0.31) and ripping (3.34hr/ha±0.53) and disc harrowing (3.30hr/ha±0.16). Further, fuel consumption and labor on no-till plots were significantly different from both the ripped and disc-harrowed plots. The high seed emergence percentage on maize disc-harrowed plot (93.75%±5.87) was not significantly different from ripping and no-till plots. Again, the high seed emergence percentage for the soybean ripped plot (93.75%±13.03) had no significant difference with discing and ripping. The results show that it is economically sound and timesaving to practice MCA and get viable yields compared to conventional farming. This research fills the gap on the potential of MCA in the context of Zambia and its profitability in incentivizing policymakers to invest in appropriate and sustainable machinery and implements for extensive agricultural production.Keywords: climate-smart agriculture, labor cost, mechanized conservation agriculture, soil moisture, Zambia
Procedia PDF Downloads 1553431 Tackling the Decontamination Challenge: Nanorecycling of Plastic Waste
Authors: Jocelyn Doucet, Jean-Philippe Laviolette, Ali Eslami
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The end-of-life management and recycling of polymer wastes remains a key environment issue in on-going efforts to increase resource efficiency and attaining GHG emission reduction targets. Half of all the plastics ever produced were made in the last 13 years, and only about 16% of that plastic waste is collected for recycling, while 25% is incinerated, 40% is landfilled, and 19% is unmanaged and leaks in the environment and waterways. In addition to the plastic collection issue, the UN recently published a report on chemicals in plastics, which adds another layer of challenge when integrating recycled content containing toxic products into new products. To tackle these important issues, innovative solutions are required. Chemical recycling of plastics provides new complementary alternatives to the current recycled plastic market by converting waste material into a high value chemical commodity that can be reintegrated in a variety of applications, making the total market size of the output – virgin-like, high value products - larger than the market size of the input – plastic waste. Access to high-quality feedstock also remains a major obstacle, primarily due to material contamination issues. Pyrowave approaches this challenge with its innovative nano-recycling technology, which purifies polymers at the molecular level, removing undesirable contaminants and restoring the resin to its virgin state without having to depolymerise it. This breakthrough approach expands the range of plastics that can be effectively recycled, including mixed plastics with various contaminants such as lead, inorganic pigments, and flame retardants. The technology allows yields below 100ppm, and purity can be adjusted to an infinitesimal level depending on the customer's specifications. The separation of the polymer and contaminants in Pyrowave's nano-recycling process offers the unique ability to customize the solution on targeted additives and contaminants to be removed based on the difference in molecular size. This precise control enables the attainment of a final polymer purity equivalent to virgin resin. The patented process involves dissolving the contaminated material using a specially formulated solvent, purifying the mixture at the molecular level, and subsequently extracting the solvent to yield a purified polymer resin that can directly be reintegrated in new products without further treatment. Notably, this technology offers simplicity, effectiveness, and flexibility while minimizing environmental impact and preserving valuable resources in the manufacturing circuit. Pyrowave has successfully applied this nano-recycling technology to decontaminate polymers and supply purified, high-quality recycled plastics to critical industries, including food-contact compliance. The technology is low-carbon, electrified, and provides 100% traceable resins with properties identical to those of virgin resins. Additionally, the issue of low recycling rates and the limited market for traditionally hard-to-recycle plastic waste has fueled the need for new complementary alternatives. Chemical recycling, such as Pyrowave's microwave depolymerization, presents a sustainable and efficient solution by converting plastic waste into high-value commodities. By employing microwave catalytic depolymerization, Pyrowave enables a truly circular economy of plastics, particularly in treating polystyrene waste to produce virgin-like styrene monomers. This revolutionary approach boasts low energy consumption, high yields, and a reduced carbon footprint. Pyrowave offers a portfolio of sustainable, low-carbon, electric solutions to give plastic waste a second life and paves the way to the new circular economy of plastics. Here, particularly for polystyrene, we show that styrene monomer yields from Pyrowave’s polystyrene microwave depolymerization reactor is 2,2 to 1,5 times higher than that of the thermal conventional pyrolysis. In addition, we provide a detailed understanding of the microwave assisted depolymerization via analyzing the effects of microwave power, pyrolysis time, microwave receptor and temperature on the styrene product yields. Furthermore, we investigate life cycle environmental impact assessment of microwave assisted pyrolysis of polystyrene in commercial-scale production. Finally, it is worth pointing out that Pyrowave is able to treat several tons of polystyrene to produce virgin styrene monomers and manage waste/contaminated polymeric materials as well in a truly circular economy.Keywords: nanorecycling, nanomaterials, plastic recycling, depolymerization
Procedia PDF Downloads 703430 Variation of Phenolic Compounds in Latvian Apple Juices and Their Suitability for Cider Production
Authors: Rita Riekstina-Dolge, Zanda Kruma, Fredijs Dimins, Inta Krasnova, Daina Karklina
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Apple juice is the main raw material for cider production. In this study apple juices obtained from 14 dessert and crab apples grown in Latvia were investigated. For all samples total phenolic compounds, tannins and individual phenolic compounds content were determined. The total phenolic content of different variety apple juices ranged from 650mg L-1 to 4265mg L-1. Chlorogenic acid is the predominant phenolic compound in all juice samples and ranged from 143.99mg L-1 in ‘Quaker Beauty’ apple juice to 617.66mg L-1 in ‘Kerr’ juice. Some dessert and crab apple juices have similar phenolic composition, but in several varieties such as ‘Cornelie’, ‘Hyslop’ and ‘Riku’ it was significantly higher. For cider production it is better to blend different kinds of apple juices including apples rich in high phenol content ('Rick', 'Cornelie') and also, for successful fermentation, apples rich in sugars and soluble solids content should be used in blends.Keywords: apple juice, phenolic compounds, hierarchical cluster analysis, cider production
Procedia PDF Downloads 4373429 The Influence of Gender on Itraconazole Pharmacokinetic Parameters in Healthy Adults
Authors: Milijana N. Miljkovic, Viktorija M. Dragojevic-Simic, Nemanja K. Rancic, Vesna M. Jacevic, Snezana B. Djordjevic, Momir M. Mikov, Aleksandra M. Kovacevic
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Itraconazole (ITZ) is a weak base and extremely lipophilic compound, with water solubility as a rate-limiting step in its absorption from the gastrointestinal tract. Its absolute bioavailability, about 55%, is maximal when its oral formulation, capsules, are taken immediately after a full meal. Peak plasma concentrations (Cmax) are reached within 2 to 5 hrs after their administration. ITZ undergoes extensive hepatic metabolism by human CYP3A4 isoenzyme and more than 30 different metabolites have been identified. One of the main ones is hydroxyitraconazole (HITZ), in which plasma concentrations are almost twice higher than those of ITZ. Gender differences in drug PK (Pharmacokinetics) have already been recognized, but variations in metabolism are believed to be their major cause. The aim of the study was to investigate the influence of gender on ITZ PK parameters after administration of oral capsule formulation, following 100 mg single dosing in healthy adult volunteers under fed conditions. The single-center, open-label PK study was performed. PK analyses included PK parameters obtained after a single 100 mg dose administration of itraconazole capsules to 48 females and 66 males. Blood samples were collected at pre-dose and up to 72.0 h after administration (1.0, 2.0, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 7.0, 9.0, 12.0, 24.0, 36.0 and 72.0 hrs). The calculated pharmacokinetic parameters, based on the plasma concentrations of itraconazole and hydroxyitraconazole, were Cmax, AUClast, and AUCtot. Plasma concentrations of ITZ and HITZ were determined using a validated liquid chromatographic method with mass spectrometric detection, while pharmacokinetic parameters were estimated using non-compartmental methods. The pharmacokinetic analyses were performed using Kinetica software version 5.0. The mean value of ITZ Cmaxmen was 74.79 ng/ml, and Cmaxwomen was 51.291 ng/ml (independent samples test; p = 0.005). Hydroxyitraconazole had a mean value of Cmaxmen 106.37 ng/ml, and the mean value Cmaxwomen was 70.05 ng/ml. Women had, on average, lower AUClast and Cmax than men. AUClastmen for ITZ was 736.02 ng/mL*h and AUClastwomen was 566.62 ng/mL*h, while AUClastmen for HITZ was 1154.80 was ng/mL*h and AUClastwomen for HITZ was 708.12 ng/mL*h (independent samples test; p = 0.033). The mean values of ITZ AUCtotmen were 884.73 ng/mL*h and AUCtotwomen was 685.10 ng/mL*h. AUCtotmen for HITZ was 1290.41 ng/mL*h, while AUCtotwomen for HIZT was 788.60 ng/mL*h (p < 0.001). The results could point out to lower oral bioavailability of ITZ in women, since values of Cmax, AUClast, and AUCtot of both ITZ and HITZ were significantly lower in women than in men, respectively. The reason may be higher expression and activity of CYP3A4 in women than in men, but there also may be differences in other PK parameters. High variability of both ITZ and HITZ concentrations in both genders confirmed that ITZ is a highly variable drug. Further examinations of its PK are needed to justify strategies for therapeutic drug monitoring in patients treated by this antifungal agent.Keywords: itraconazole, gender, hydroxyitraconazole, pharmacokinetics
Procedia PDF Downloads 1393428 Failure Analysis and Fatigue Life Estimation of a Shaft of a Rotary Draw Bending Machine
Authors: B. Engel, Sara Salman Hassan Al-Maeeni
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Human consumption of the Earth's resources increases the need for a sustainable development as an important ecological, social, and economic theme. Re-engineering of machine tools, in terms of design and failure analysis, is defined as steps performed on an obsolete machine to return it to a new machine with the warranty that matches the customer requirement. To understand the future fatigue behavior of the used machine components, it is important to investigate the possible causes of machine parts failure through design, surface, and material inspections. In this study, the failure modes of the shaft of the rotary draw bending machine are inspected. Furthermore, stress and deflection analysis of the shaft subjected to combined torsion and bending loads are carried out by an analytical method and compared with a finite element analysis method. The theoretical fatigue strength, correction factors, and fatigue life sustained by the shaft before damaged are estimated by creating a stress-cycle (S-N) diagram. In conclusion, it is seen that the shaft can work in the second life, but it needs some surface treatments to increase the reliability and fatigue life.Keywords: failure analysis, fatigue life, FEM analysis, shaft, stress analysis
Procedia PDF Downloads 3113427 Seismic Assessment of Old Existing RC Buildings with Masonry Infill in Madinah as Per ASCE
Authors: Tarek M. Alguhane, Ayman H. Khalil, Nour M. Fayed, Ayman M. Ismail
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An existing RC building in Madinah is seismically evaluated with and without infill wall. Four model systems have been considered i. e. model I (no infill), model IIA (strut infill-update from field test), model IIB (strut infill- ASCE/SEI 41) and model IIC (strut infill-Soft storey-ASCE/SEI 41). Three dimensional pushover analyses have been carried out using SAP 2000 software incorporating inelastic material behavior for concrete, steel and infill walls. Infill wall has been modeled as equivalent strut according to suggested equation matching field test measurements and to the ASCE/SEI 41 equation. The effect of building modeling on the performance point as well as capacity and demand spectra due to EQ design spectrum function in Madinah area has been investigated. The response modification factor (R) for the 5 story RC building is evaluated from capacity and demand spectra (ATC-40) for the studied models. The results are summarized and discussed.Keywords: infill wall, pushover analysis, response modification factor, seismic assessment
Procedia PDF Downloads 3943426 Interesting Behavior of Non-Thermal Plasma Photonic Crystals
Authors: A. Mousavi, S. Sadegzadeh
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In this research, the effect of non-thermal micro plasma with non-Maxwellian distribution function on the one dimensional plasma photonic crystals containing alternate plasma-dielectric layers, has been studied. By using Kronig Penny model, the dispersion relation of electromagnetic modes for such a periodic structure is obtained. In this study we take two plasma photonic crystals with different dielectric layers: the first one with Silicon monoxide named PPCI, and the second one with Tellurium dioxide named PPCII. The effects of the plasma layer thickness and the material of the dielectric layer on the plasma photonic crystal band gaps have been illustrated in the dispersion relation and the group velocity figures. Results revealed that in such a system, the non-thermal plasma exerts stronger limit on the wave’s propagation. In another word, for the non-thermal plasma photonic crystals (NPPC), there are two distinct regions in the dispersion plot. The upper region consists of alternate band gaps in such a way that both width and length of the bands decrease gradually as the band gaps order increases. Whereas in the lower region where v_ph > 20 c (for PPCI), waves will not be allowed to propagate.Keywords: band gap, dispersion relation, non-thermal plasma, plasma photonic crystal
Procedia PDF Downloads 5433425 Causes of Institutionalization of Children and Adolescents in a Shelter in Brazil
Authors: Eduardo Guilherme, Sabrina Duarte
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Shelters or orphanages are institutions responsible for ensuring the physical and mental integrity of children and adolescents who had their rights violated or neglected, whether from a social-leavers, is at personal risk to which they were exposed or the negligence of its parents; in Brazil about twenty thousand children and adolescents living in about five hundred registered shelters that receive funds from the federal government. We evaluated the records of institutionalized children and adolescents from the foundation of municipal shelter in Rio Negro/Parana State, Brazil since June/2000 to February/2015. Institutionalization of the causes cited were: lack of family/guardian material resources, abandonment by parents/guardians, domestic violence, substance abuse of parents/guardians, street experience, orphans and others. In Brazil, poverty and extreme poverty are closely related to the institutionalization of causes of children and adolescents. Census data in 2010, the Brazilian Institute of Geography and Statistics (IBGE) indicate that 40% of Brazilians living in poverty are girls and boys up to 14 years in a total of approximately 23 million individuals. Poverty denies children and adolescents their rights, representing a vulnerability which predisposes to some causes of shelter.Keywords: Brazil, shelter, orphanages, institutionalization
Procedia PDF Downloads 4903424 Ragging and Sludging Measurement in Membrane Bioreactors
Authors: Pompilia Buzatu, Hazim Qiblawey, Albert Odai, Jana Jamaleddin, Mustafa Nasser, Simon J. Judd
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Membrane bioreactor (MBR) technology is challenged by the tendency for the membrane permeability to decrease due to ‘clogging’. Clogging includes ‘sludging’, the filling of the membrane channels with sludge solids, and ‘ragging’, the aggregation of short filaments to form long rag-like particles. Both sludging and ragging demand manual intervention to clear out the solids, which is time-consuming, labour-intensive and potentially damaging to the membranes. These factors impact on costs more significantly than membrane surface fouling which, unlike clogging, is largely mitigated by the chemical clean. However, practical evaluation of MBR clogging has thus far been limited. This paper presents the results of recent work attempting to quantify sludging and clogging based on simple bench-scale tests. Results from a novel ragging simulation trial indicated that rags can be formed within 24-36 hours from dispersed < 5 mm-long filaments at concentrations of 5-10 mg/L under gently agitated conditions. Rag formation occurred for both a cotton wool standard and samples taken from an operating municipal MBR, with between 15% and 75% of the added fibrous material forming a single rag. The extent of rag formation depended both on the material type or origin – lint from laundering operations forming zero rags – and the filament length. Sludging rates were quantified using a bespoke parallel-channel test cell representing the membrane channels of an immersed flat sheet MBR. Sludge samples were provided from two local MBRs, one treating municipal and the other industrial effluent. Bulk sludge properties measured comprised mixed liquor suspended solids (MLSS) concentration, capillary suction time (CST), particle size, soluble COD (sCOD) and rheology (apparent viscosity μₐ vs shear rate γ). The fouling and sludging propensity of the sludge was determined using the test cell, ‘fouling’ being quantified as the pressure incline rate against flux via the flux step test (for which clogging was absent) and sludging by photographing the channel and processing the image to determine the ratio of the clogged to unclogged regions. A substantial difference in rheological and fouling behaviour was evident between the two sludge sources, the industrial sludge having a higher viscosity but less shear-thinning than the municipal. Fouling, as manifested by the pressure increase Δp/Δt, as a function of flux from classic flux-step experiments (where no clogging was evident), was more rapid for the industrial sludge. Across all samples of both sludge origins the expected trend of increased fouling propensity with increased CST and sCOD was demonstrated, whereas no correlation was observed between clogging rate and these parameters. The relative contribution of fouling and clogging was appraised by adjusting the clogging propensity via increasing the MLSS both with and without a commensurate increase in the COD. Results indicated that whereas for the municipal sludge the fouling propensity was affected by the increased sCOD, there was no associated increased in the sludging propensity (or cake formation). The clogging rate actually decreased on increasing the MLSS. Against this, for the industrial sludge the clogging rate dramatically increased with solids concentration despite a decrease in the soluble COD. From this was surmised that sludging did not relate to fouling.Keywords: clogging, membrane bioreactors, ragging, sludge
Procedia PDF Downloads 1863423 Wideband Performance Analysis of C-FDTD Based Algorithms in the Discretization Impoverishment of a Curved Surface
Authors: Lucas L. L. Fortes, Sandro T. M. Gonçalves
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In this work, it is analyzed the wideband performance with the mesh discretization impoverishment of the Conformal Finite Difference Time-Domain (C-FDTD) approaches developed by Raj Mittra, Supriyo Dey and Wenhua Yu for the Finite Difference Time-Domain (FDTD) method. These approaches are a simple and efficient way to optimize the scattering simulation of curved surfaces for Dielectric and Perfect Electric Conducting (PEC) structures in the FDTD method, since curved surfaces require dense meshes to reduce the error introduced due to the surface staircasing. Defined, on this work, as D-FDTD-Diel and D-FDTD-PEC, these approaches are well-known in the literature, but the improvement upon their application is not quantified broadly regarding wide frequency bands and poorly discretized meshes. Both approaches bring improvement of the accuracy of the simulation without requiring dense meshes, also making it possible to explore poorly discretized meshes which bring a reduction in simulation time and the computational expense while retaining a desired accuracy. However, their applications present limitations regarding the mesh impoverishment and the frequency range desired. Therefore, the goal of this work is to explore the approaches regarding both the wideband and mesh impoverishment performance to bring a wider insight over these aspects in FDTD applications. The D-FDTD-Diel approach consists in modifying the electric field update in the cells intersected by the dielectric surface, taking into account the amount of dielectric material within the mesh cells edges. By taking into account the intersections, the D-FDTD-Diel provides accuracy improvement at the cost of computational preprocessing, which is a fair trade-off, since the update modification is quite simple. Likewise, the D-FDTD-PEC approach consists in modifying the magnetic field update, taking into account the PEC curved surface intersections within the mesh cells and, considering a PEC structure in vacuum, the air portion that fills the intersected cells when updating the magnetic fields values. Also likewise to D-FDTD-Diel, the D-FDTD-PEC provides a better accuracy at the cost of computational preprocessing, although with a drawback of having to meet stability criterion requirements. The algorithms are formulated and applied to a PEC and a dielectric spherical scattering surface with meshes presenting different levels of discretization, with Polytetrafluoroethylene (PTFE) as the dielectric, being a very common material in coaxial cables and connectors for radiofrequency (RF) and wideband application. The accuracy of the algorithms is quantified, showing the approaches wideband performance drop along with the mesh impoverishment. The benefits in computational efficiency, simulation time and accuracy are also shown and discussed, according to the frequency range desired, showing that poorly discretized mesh FDTD simulations can be exploited more efficiently, retaining the desired accuracy. The results obtained provided a broader insight over the limitations in the application of the C-FDTD approaches in poorly discretized and wide frequency band simulations for Dielectric and PEC curved surfaces, which are not clearly defined or detailed in the literature and are, therefore, a novelty. These approaches are also expected to be applied in the modeling of curved RF components for wideband and high-speed communication devices in future works.Keywords: accuracy, computational efficiency, finite difference time-domain, mesh impoverishment
Procedia PDF Downloads 1383422 Study of the Influence of Hole Topology on Crack Propagation Rate
Authors: Hallan Moura Ladeira, Carla Tatiana Mota Anflor
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The drilling process for bolted or riveted joints of components is very common in the naval, aeronautical, mechanical, and civil industries. In this context, the present work aims to study, through computer simulation, the influence of hole geometry (through, chamfered, and rounded) on crack propagation when submitted to static and dynamic loads. For the static crack evaluation, failure was considered when the stress intensity factor (FIT) exceeds the fracture toughness of the material (KIc). In the case of fatigue, the condition of the small crack tip plastification zone and the Paris Law were considered for determining region II of the dadN x ΔK curve. Initially, a parametric analysis of the hole geometry was performed to obtain a topology that would result in less discontinuity of the stress field and, consequently, less influence on static crack growth. The best performing topology was then used to study the fatigue crack growth rate considering the Paris Law. The numerical tests were performed on a 7075-T6 aluminum specimen resulting in dadN x ΔK curves in good agreement with the literature.Keywords: holes, cracks, loading, fracture toughness
Procedia PDF Downloads 1193421 The Efficacy of Thymbra spicata Ethanolic Extract and its Main Component Carvacrol on In vitro Model of Metabolically-Associated Dysfunctions
Authors: Farah Diab, Mohamad Khalil, Francesca Storace, Francesca Baldini, Piero Portincasaa, Giulio Lupidi, Laura Vergani
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Thymbra spicata is a thyme-like plant belonging to the Lamiaceae family that shows a global distribution, especially in the eastern Mediterranean region. Leaves of T. spicata contain large amounts of phenols such as phenolic acids (rosmarinic acid), phenolic monoterpenes (carvacrol), and flavonoids. In Lebanon, T. spicata is currently used as a culinary herb in salad and infusion, as well as for traditional medicinal purposes. Carvacrol (5-isopropyl-2-methyl phenol), the most abundant polyphenol in the organic extract and essential oils, has a great array of pharmacological properties. In fact, carvacrol is largely employed as a food additive and neutraceutical agent. Our aim is to investigate the beneficial effects of T. spicata ethanolic extract (TE) and its main component, carvacrol, using in vitro models of hepatic steatosis and endothelial dysfunction. As a further point, we focused on investigating if and how the binding of carvacrol to albumin, the physiological transporter for drugs in the blood, might be altered by the presence of high levels of fatty acids (FAs), thus impairing the carvacrol bio-distribution in vivo. For that reason, hepatic FaO cells treated with exogenous FAs such as oleate and palmitate mimic hepatosteatosis; endothelial HECV cells exposed to hydrogen peroxide are a model of endothelial dysfunction. In these models, we measured lipid accumulation, free radical production, lipoperoxidation, and nitric oxide release before and after treatment with carvacrol. The carvacrol binding to albumin with/without high levels of long-chain FAs was assessed by absorption and emission spectroscopies. Our findings show that both TE and carvacrol (i) counteracted lipid accumulation in hepatocytes by decreasing the intracellular and extracellular lipid contents in steatotic FaO cells; (ii) decreased oxidative stress in endothelial cells by significantly reducing lipoperoxidation and free radical production, as well as, attenuating the nitric oxide release; (ii) high levels of circulating FAs reduced the binding of carvacrol to albumin. The beneficial effects of TE and carvacrol on both hepatic and endothelial cells point to a nutraceutical potential. However, high levels of circulating FAs, such as those occurring in metabolic disorders, might hinder the carvacrol transport, bio-distribution, and pharmacodynamics.Keywords: carvacrol, endothelial dysfunction, fatty acids, non-alcoholic fatty liver diseases, serum albumin
Procedia PDF Downloads 1983420 Negative Environmental Impacts on Marine Seismic Survey Activities
Authors: Katherine Del Carmen Camacho Zorogastua, Victor Hugo Gallo Ramos, Jhon Walter Gomez Lora
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Marine hydrocarbon exploration (oil and natural gas) activities are developed using 2D, 3D and 4D seismic prospecting techniques where sound waves are directed from a seismic vessel emitted every few seconds depending on the variety of air compressors, which cross the layers of rock at the bottom of the sea and are reflected to the surface of the water. Hydrophones receive and record the reflected energy signals for cross-sectional mapping of the lithological profile in order to identify possible areas where hydrocarbon deposits can be formed. However, they produce several significant negative environmental impacts on the marine ecosystem and in the social and economic sectors. Therefore, the objective of the research is to publicize the negative impacts and environmental measures that must be carried out during the development of these activities to prevent and mitigate water quality, the population involved (fishermen) and the marine biota (e.g., Cetaceans, fish) that are the most vulnerable. The research contains technical environmental aspects based on bibliographic sources of environmental studies approved by the Peruvian authority, research articles, undergraduate and postgraduate theses, books, guides, and manuals from Spain, Australia, Canada, Brazil, and Mexico. It describes the negative impacts on the environment and population (fishing sector), environmental prevention, mitigation, recovery and compensation measures that must be properly implemented and the cases of global sea species stranding, for which international experiences from Spain, Madagascar, Mexico, Ecuador, Uruguay, and Peru were referenced. Negative impacts on marine fauna, seawater quality, and the socioeconomic sector (fishermen) were identified. Omission or inadequate biological monitoring in mammals could alter their ability to communicate, feed, and displacement resulting in their stranding and death. In fish, they cause deadly damage to physical-physiological type and in their behavior. Inadequate wastewater treatment and waste management could increase the organic load and oily waste on seawater quality in violation of marine flora and fauna. The possible estrangement of marine resources (fish) affects the economic sector as they carry out their fishing activity for consumption or sale. Finally, it is concluded from the experiences gathered from Spain, Madagascar, Mexico, Ecuador, Uruguay, and Peru that there is a cause and effect relationship between the inadequate development of seismic exploration activities (cause) and marine species strandings (effect) since over the years, stranded or dead marine mammals have been detected on the shores of the sea in areas of seismic acquisition of hydrocarbons. In this regard, it is recommended to establish technical procedures, guidelines, and protocols for the monitoring of marine species in order to contribute to the conservation of hydrobiological resources.Keywords: 3D seismic prospecting, cetaceans, significant environmental impacts, prevention, mitigation, recovery, environmental compensation
Procedia PDF Downloads 1933419 A Next-Generation Pin-On-Plate Tribometer for Use in Arthroplasty Material Performance Research
Authors: Lewis J. Woollin, Robert I. Davidson, Paul Watson, Philip J. Hyde
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Introduction: In-vitro testing of arthroplasty materials is of paramount importance when ensuring that they can withstand the performance requirements encountered in-vivo. One common machine used for in-vitro testing is a pin-on-plate tribometer, an early stage screening device that generates data on the wear characteristics of arthroplasty bearing materials. These devices test vertically loaded rotating cylindrical pins acting against reciprocating plates, representing the bearing surfaces. In this study, a pin-on-plate machine has been developed that provides several improvements over current technology, thereby progressing arthroplasty bearing research. Historically, pin-on-plate tribometers have been used to investigate the performance of arthroplasty bearing materials under conditions commonly encountered during a standard gait cycle; nominal operating pressures of 2-6 MPa and an operating frequency of 1 Hz are typical. There has been increased interest in using pin-on-plate machines to test more representative in-vivo conditions, due to the drive to test 'beyond compliance', as well as their testing speed and economic advantages over hip simulators. Current pin-on-plate machines do not accommodate the increased performance requirements associated with more extreme kinematic conditions, therefore a next-generation pin-on-plate tribometer has been developed to bridge the gap between current technology and future research requirements. Methodology: The design was driven by several physiologically relevant requirements. Firstly, an increased loading capacity was essential to replicate the peak pressures that occur in the natural hip joint during running and chair-rising, as well as increasing the understanding of wear rates in obese patients. Secondly, the introduction of mid-cycle load variation was of paramount importance, as this allows for an approximation of the loads present in a gait cycle to be applied and to test the fatigue properties of materials. Finally, the rig must be validated against previous-generation pin-on-plate and arthroplasty wear data. Results: The resulting machine is a twelve station device that is split into three sets of four stations, providing an increased testing capacity compared to most current pin-on-plate tribometers. The loading of the pins is generated using a pneumatic system, which can produce contact pressures of up to 201 MPa on a 3.2 mm² round pin face. This greatly exceeds currently achievable contact pressures in literature and opens new research avenues such as testing rim wear of mal-positioned hip implants. Additionally, the contact pressure of each set can be changed independently of the others, allowing multiple loading conditions to be tested simultaneously. Using pneumatics also allows the applied pressure to be switched ON/OFF mid-cycle, another feature not currently reported elsewhere, which allows for investigation into intermittent loading and material fatigue. The device is currently undergoing a series of validation tests using Ultra-High-Molecular-Weight-Polyethylene pins and 316L Stainless Steel Plates (polished to a Ra < 0.05 µm). The operating pressures will be between 2-6 MPa, operating at 1 Hz, allowing for validation of the machine against results reported previously in the literature. The successful production of this next-generation pin-on-plate tribometer will, following its validation, unlock multiple previously unavailable research avenues.Keywords: arthroplasty, mechanical design, pin-on-plate, total joint replacement, wear testing
Procedia PDF Downloads 983418 Aquafaba Derived from Korean Soybean Cultivars: A Novel Vegan Egg Replacer
Authors: Yue He, Youn Young Shim, Ji Hye Kim, Jae Youl Cho, Martin J. T. Reaney
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Recently, pulse cooking water (a.k.a. Aquafaba) has been used as an important and cost-effective alternative to eggs in gluten-free, vegan cooking and baking applications. The aquafaba (AQ) is primarily due to its excellent ability to stabilize foams and emulsions in foods. However, the functional ingredients of this excellent AQ are usually discarded with the compound release. This study developed a high-functional food material, AQ, using functional soybean AQ that has not been studied in Korea. A zero-waste and cost-effective hybrid process were used to produce oil emulsifiers from Korean soybeans. The treatment technique was implemented using a small number of efficient steps. Aquafaba from Backtae had the best emulsion properties (92%) and has the potential to produce more stable food oil emulsions. Therefore, this study is expected to be utilized in the development of the first gluten-free, vegan product for vegetarians and consumers with animal protein allergies, utilizing wastewater from cooked soybeans as a source of plant protein that can replace animal protein.Keywords: aquafaba, soybean, chickpea, emulsifiers, egg replacer, egg-free products
Procedia PDF Downloads 1823417 Evaluation of Fuel Properties of Six Tropical Hardwood Timber Species for Briquettes
Authors: Stephen J. Mitchual, Kwasi Frimpong-Mensah, Nicholas A. Darkwa
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The fuel potential of six tropical hardwood species namely: Triplochiton scleroxylon, Ceiba pentandra, Aningeria robusta, Terminalia superba, Celtis mildbreadii and Piptadenia africana were studied. Properties studied include the species density, gross calorific value, volatile matter, ash, organic carbon, N, H, S, Cu, Pb, As and Cd content. Fuel properties were determined using standard laboratory methods. The result indicates that the Gross Calorific Value (GCV) of the species ranged from 20.16 to 22.22 MJ/kg and they slightly varied from each other. Additionally, the GCV of the biomass materials were higher than that of other biomass materials like; wheat straw, rice straw, maize straw and sugar cane. The ash and volatile matter content varied from 0.6075 to 5.0407%, and 75.23% to 83.70% respectively. The overall rating of the properties of the six biomass materials suggest that Piptadenia africana has the best fuel property to be used as briquettes and Aningeria robusta the worse. This study therefore suggests that a holistic assessment of a biomass material needs to be done before selecting it for fuel purpose.Keywords: ash content, briquette, calorific value, elemental composition, species, volatile matter
Procedia PDF Downloads 431