Search results for: concrete waste
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4323

Search results for: concrete waste

663 Numerical Assessment of Fire Characteristics with Bodies Engulfed in Hydrocarbon Pool Fire

Authors: Siva Kumar Bathina, Sudheer Siddapureddy

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Fires accident becomes even worse when the hazardous equipment like reactors or radioactive waste packages are engulfed in fire. In this work, large-eddy numerical fire simulations are performed using fire dynamic simulator to predict the thermal behavior of such bodies engulfed in hydrocarbon pool fires. A radiatively dominated 0.3 m circular burner with n-heptane as the fuel is considered in this work. The fire numerical simulation results without anybody inside the fire are validated with the reported experimental data. The comparison is in good agreement for different flame properties like predicted mass burning rate, flame height, time-averaged center-line temperature, time-averaged center-line velocity, puffing frequency, the irradiance at the surroundings, and the radiative heat feedback to the pool surface. Cask of different sizes is simulated with SS304L material. The results are independent of the material of the cask simulated as the adiabatic surface temperature concept is employed in this study. It is observed that the mass burning rate increases with the blockage ratio (3% ≤ B ≤ 32%). However, the change in this increment is reduced at higher blockage ratios (B > 14%). This is because the radiative heat feedback to the fuel surface is not only from the flame but also from the cask volume. As B increases, the volume of the cask increases and thereby increases the radiative contribution to the fuel surface. The radiative heat feedback in the case of the cask engulfed in the fire is increased by 2.5% to 31% compared to the fire without cask.

Keywords: adiabatic surface temperature, fire accidents, fire dynamic simulator, radiative heat feedback

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662 Association of Antibiotics Resistance with Efflux Pumps Genes among Multidrug-Resistant Klebsiella pneumonia Recovered from Hospital Waste Water Effluents in Eastern Cape, South Africa

Authors: Okafor Joan, Nwodo Uchechukwu

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Klebsiella pneumoniae (K. pneumoniae) is a significant pathogen responsible for opportunistic and nosocomial infection. One of the most significant antibiotic resistance mechanisms in K. pneumoniae isolates is efflux pumps. Our current study identified efflux genes (AcrAB, OqxAB, MacAB, and TolC) and regulatory genes (RamR and RarA) in multidrug-resistant (MDR) K. pneumoniae isolated from hospital effluents and investigated their relationship with antibiotic resistance. The sum of 145 K. pneumoniae isolates was established by PCR and screened for antibiotic susceptibility. PCR detected efflux pump genes, and their link with antibiotic resistance was statistically examined. However, 120 (83%) of the confirmed isolated were multidrug-resistant, with the largest percentage of resistance to ampicillin (88.3%) and the weakest rate of resistance to imipenem (5.5%). Resistance to the other antibiotics ranged from 11% to 76.6%. Molecular distribution tests show that AcrA, AcrB, MacA, oqxB oqxA, TolC, MacB were detected in 96.7%, 85%, 76.7%, 70.8%, 55.8%, 39.1%, and 29.1% respectively. However, 14.3% of the isolates harboured all seven genes screened. Efflux pump system AcrAB (83.2%) was the most commonly detected in K. pneumonia isolated across all the antibiotics class-tested. In addition, the frequencies of RamR and RarA were 46.2% and 31.4%, respectively. AcrAB and OqxAB efflux pump genes were significantly associated with fluoroquinolone, beta-lactam, carbapenem, and tetracycline resistance (p<0.05). The high rate of efflux genes in this study demonstrated that this resistance mechanism is the dominant way in K. pneumoniae isolates. Appropriate treatment must be used to reduce and tackle the burden of resistant Klebsiella pneumonia in hospital wastewater effluents.

Keywords: Klebsiella pneumonia, efflux pumps, regulatory genes, multidrug-resistant, hospital, PCR

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661 Management Prospects of Winery By-Products Based on Phenolic Compounds and Antioxidant Activity of Grape Skins: The Case of Greek Ionian Islands

Authors: Marinos Xagoraris, Iliada K. Lappa, Charalambos Kanakis, Dimitra Daferera, Christina Papadopoulou, Georgios Sourounis, Charilaos Giotis, Pavlos Bouchagier, Christos S. Pappas, Petros A. Tarantilis, Efstathia Skotti

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The aim of this work was to recover phenolic compounds from grape skins produced in Greek varieties of the Ionian Islands in order to form the basis of calculations for their further utilization in the context of the circular economy. Isolation and further utilization of phenolic compounds is an important issue in winery by-products. For this purpose, 37 samples were collected, extracted, and analyzed in an attempt to provide the appropriate basis for their sustainable exploitation. Extraction of the bioactive compounds was held using an eco-friendly, non-toxic, and highly effective water-glycerol solvent system. Then, extracts were analyzed using UV-Vis, liquid chromatography-mass spectrometry (LC-MS), FTIR, and Raman spectroscopy. Also, total phenolic content and antioxidant activity were measured. LC-MS chromatography showed qualitative differences between different varieties. Peaks were attributed to monomeric 3-flavanols as well as monomeric, dimeric, and trimeric proanthocyanidins. The FT-IR and Raman spectra agreed with the chromatographic data and contributed to identifying phenolic compounds. Grape skins exhibited high total phenolic content (TPC), and it was proved that during vinification, a large number of polyphenols remained in the pomace. This study confirmed that grape skins from Ionian Islands are a promising source of bioactive compounds, suggesting their utilization under a bio-economic and environmental strategic framework.

Keywords: antioxidant activity, grape skin, phenolic compounds, waste recovery

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660 Improving Cleanability by Changing Fish Processing Equipment Design

Authors: Lars A. L. Giske, Ola J. Mork, Emil Bjoerlykhaug

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The design of fish processing equipment greatly impacts how easy the cleaning process for the equipment is. This is a critical issue in fish processing, as cleaning of fish processing equipment is a task that is both costly and time consuming, in addition to being very important with regards to product quality. Even more, poorly cleaned equipment could in the worst case lead to contaminated product from which consumers could get ill. This paper will elucidate how equipment design changes could improve the work for the cleaners and saving money for the fish processing facilities by looking at a case for product design improvements. The design of fish processing equipment largely determines how easy it is to clean. “Design for cleaning” is the new hype in the industry and equipment where the ease of cleaning is prioritized gets a competitive advantage over equipment in which design for cleaning has not been prioritized. Design for cleaning is an important research area for equipment manufacturers. SeaSide AS is doing continuously improvements in the design of their products in order to gain a competitive advantage. The focus in this paper will be conveyors for internal logistic and a product called the “electro stunner” will be studied with regards to “Design for cleaning”. Often together with SeaSide’s customers, ideas for new products or product improvements are sketched out, 3D-modelled, discussed, revised, built and delivered. Feedback from the customers is taken into consideration, and the product design is revised once again. This loop was repeated multiple times, and led to new product designs. The new designs sometimes also cause the manufacturing processes to change (as in going from bolted to welded connections). Customers report back that the concrete changes applied to products by SeaSide has resulted in overall more easily cleaned equipment. These changes include, but are not limited to; welded connections (opposed to bolted connections), gaps between contact faces, opening up structures to allow cleaning “inside” equipment, and generally avoiding areas in which humidity and water may gather and build up. This is important, as there will always be bacteria in the water which will grow if the area never dries up. The work of creating more cleanable design is still ongoing, and will “never” be finished as new designs and new equipment will have their own challenges.

Keywords: cleaning, design, equipment, fish processing, innovation

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659 Higher Education Leadership and Creating Sites of Institutional Belonging: A Global Case Study

Authors: Lisa M. Coleman

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The focus on disability, LGBTQ+, and internationalization has certainly been the subject of much research and programmatic across higher education. Many universities have entered into global partnerships with varying success and challenges across the various areas, including laws and policies. Attentiveness to the specific nuances of global inclusion, diversity, equity, belonging, and access (GIDBEA) and the leadership to support these efforts is crucial to the development of longstanding success across the programs. There have been a number of shifts related to diversification across student and alumni bodies. These shifts include but are not limited to how people identify gender, race, and sexuality (and the intersections across such identities), as well as trends across emerging and diverse disability communities. NYU is the most international campus in the United States, with the most campuses and sites outside of its county of origin and the most international students and exchange programs than any other university. As a result, the ongoing work related to GIDEBA is at the center of much of the leadership, administrative, and research efforts. Climate assessment work across NYU’s diverse global campus landscape will serve as the foundation to exemplify best practices related to data collection and dissemination, community and stakeholder engagement, and effective implementation of innovative strategies to close gap areas as identified. The data (quantitative and qualitative) and related research findings represent data collected from close to 22,000 stakeholders across the NYU campuses. The case study centers on specific methodological considerations, data integrity, stakeholder engagement from across student-faculty, staff, and alumni constituencies, and tactics to advance specific GIDBEA initiatives related to navigating shifting landscapes. Design thinking, incubation, and co-creation strategies have been employed to expand, leverage, actualize, and implement GIDBEA strategies that are – concrete, measurable, differentiated, and specific to global sites and regions and emerging trends.

Keywords: disability, LGBTQ+, DEI, research, case studies

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658 The Applications of Toyota Production System to Reduce Wastes in Agricultural Products Packing Process: A Study of Onion Packing Plant

Authors: P. Larpsomboonchai

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Agro-industry is one of major industries that has strong impacts on national economic incomes, growth, stability, and sustainable development. Moreover, this industry also has strong influences on social, cultural and political issues. Furthermore, this industry, as producing primary and secondary products, is facing challenges from such diverse factors such as demand inconsistency, intense international competition, technological advancements and new competitors. In order to maintain and to improve industry’s competitiveness in both domestics and international markets, science and technology are key factors. Besides hard sciences and technologies, modern industrial engineering concepts such as Just in Time (JIT) Total Quality Management (TQM), Quick Response (QR), Supply Chain Management (SCM) and Lean can be very effective to supportant to increase efficiency and effectiveness of these agricultural products on world stage. Onion is one of Thailand’s major export products which brings back national incomes. But, it also facing challenges in many ways. This paper focused its interests in onion packing process and its related activities such as storage and shipment from one of major packing plant and storage in Mae Wang District, Chiang Mai, Thailand, by applying Toyota Production System (TPS) or Lean concepts, to improve process capability throughout the entire packing and distribution process which will be profitable for the whole onion supply chain. And it will be beneficial to other related agricultural products in Thailand and other ASEAN countries.

Keywords: packing process, Toyota Production System (TPS), lean concepts, waste reduction, lean in agro-industries activities

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657 Developing Sustainable Rammed Earth Material Using Pulp Mill Fly Ash as Cement Replacement

Authors: Amin Ajabi, Chinchu Cherian, Sumi Siddiqua

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Rammed earth (RE) is a traditional soil-based building material made by compressing a mixture of natural earth and binder ingredients such as chalk or lime, in temporary formworks. However, the modern RE uses 5 to 10% cement as a binder in order to meet the strength and durability requirements as per the standard specifications and guidelines. RE construction is considered to be an energy-efficient and environmental-friendly approach when compared to conventional concrete systems, which use 20 to 30% cement. The present study aimed to develop RE mix designs by utilizing non-hazardous wood-based fly ash generated by pulp and paper mills as a partial replacement for cement. The pulp mill fly ash (PPFA)-stabilized RE is considered to be a sustainable approach keeping in view of the massive carbon footprints associated with cement production as well as the adverse environmental impacts due to disposal of PPFA in landfills. For the experimental study, as-received PPFA, as well as PPFA-based geopolymer (synthesized by alkaline activation method), were incorporated as cement substitutes in the RE mixtures. Initially, local soil was collected and characterized by index and engineering properties. The PPFA was procured from a pulp manufacturing mill, and its physicochemical, mineralogical and morphological characterization, as well as environmental impact assessment, was conducted. Further, the various mix designs of RE material incorporating local soil and different proportions of cement, PPFA, and alkaline activator (a mixture of sodium silicate and sodium hydroxide solutions) were developed. The compacted RE specimens were cured and tested for 7-day and 28-day unconfined compressive strength (UCS) variations. Based on UCS results, the optimum mix design was identified corresponding to maximum strength improvement. Further, the cured RE specimens were subjected to freeze-thaw cycle testing for evaluating its performance and durability as a sustainable construction technique under extreme climatic conditions.

Keywords: sustainability, rammed earth, stabilization, pulp mill fly ash, geopolymer, alkaline activation, strength, durability

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656 Effect of Ultrasound-Assisted Pretreatment on Saccharification of Spent Coffee Grounds

Authors: Shady S. Hassan, Brijesh K. Tiwari, Gwilym A. Williams, Amit K. Jaiswal

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EU is known as the destination with the highest rate of the coffee consumption per capita in the world. Spent coffee grounds (SCG) are the main by-product of coffee brewing. SCG is either disposed as a solid waste or employed as compost, although the polysaccharides from such lignocellulosic biomass might be used as feedstock for fermentation processes. However, SCG as a lignocellulose have a complex structure and pretreatment process is required to facilitate an efficient enzymatic hydrolysis of carbohydrates. However, commonly used pretreatment methods, such as chemical, physico-chemical and biological techniques are still insufficient to meet optimal industrial production requirements in a sustainable way. Ultrasound is a promising candidate as a sustainable green pretreatment solution for lignocellulosic biomass utilization in a large scale biorefinery. Thus, ultrasound pretreatment of SCG without adding harsh chemicals investigated as a green technology to enhance enzyme hydrolysis. In the present work, ultrasound pretreatment experiments were conducted on SCG using different ultrasound frequencies (25, 35, 45, 130, and 950 kHz) for 60 min. Regardless of ultrasound power, low ultrasound frequency is more effective than high ultrasound frequency in pretreatment of biomass. Ultrasound pretreatment of SCG (at ultrasound frequency of 25 kHz for 60 min) followed by enzymatic hydrolysis resulted in total reducing sugars of 56.1 ± 2.8 mg/g of biomass. Fourier transform Infrared Spectroscopy (FTIR) was employed to investigate changes in functional groups of biomass after pretreatment, while high-performance liquid chromatography (HPLC) was employed for determination of glucose. Pretreatment of lignocellulose by low frequency ultrasound in water only was found to be an effective green approach for SCG to improve saccharification and glucose yield compared to native biomass. Pretreatment conditions will be optimized, and the enzyme hydrolysate will be used as media component substitute for the production of ethanol.

Keywords: lignocellulose, ultrasound, pretreatment, spent coffee grounds

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655 Synthesis of La0.8Sr0.05Ca0.15Fe0.8Co0.2O3-δ -Ce0.9Gd0.1O1.95 Composite Cathode Material for Solid Oxide Fuel Cell with Lanthanum and Cerium Recycled from Wasted Glass Polishing Powder

Authors: Jun-Lun Jiang, Bing-Sheng Yu

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Processing of flat-panel displays generates huge amount of wasted glass polishing powder, with high concentration of cerium and other elements such as lanthanum. According to the current statistics, consumption of polishing powder was approximately ten thousand tons per year in the world. Nevertheless, wasted polishing powder was usually buried or burned. If the lanthanum and cerium compounds in the wasted polishing powder could be recycled, that will greatly reduce enterprise cost and implement waste circulation. Cathodes of SOFCs are the principal consisting of rare earth elements such as lanthanum and cerium. In this study, we recycled the lanthanum and cerium from wasted glass polishing powder by acid-solution method, and synthesized La0.8Sr0.05Ca0.15Fe0.8Co0.8O3-δ and Gd0.1Ce0.9O2 (LSCCF-GDC) composite cathode material for SOFCs by glycinenitrate combustion (GNP) method. The results show that the recovery rates of lanthanum and cerium could accomplish up to 80% and 100% under 10N nitric acid solution within one hour. Comparing with the XRD data of the commercial LSCCF-GDC powder and the LSCCF-GDC product synthesized with chemicals, we find that the LSCCF-GDC was successfully synthesized with the recycled La & Ce solution by GNP method. The effect of adding ammonia to the product was also discussed, the grain size is finer and recovery rate of the product is higher without the addition of ammonia to the solution.

Keywords: glass polishing powder, acid solution, recycling, composite cathodes of solid oxide fuel, cell (SOFC), perovskite, glycine-nitrate combustion(GNP) method

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654 Human and Environment Coevolution: The Chalcolithic Tell Settlements from Muntenia and Dobrogea, South-Eastern Romania

Authors: Constantin Haita

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The chalcolithic tell settlements from south-eastern Romania, attributed to Gumelnița culture, are characterised by a well-defined surface, marked often by delimitation structures, a succession of many layers of construction, destruction, and rebuilding, and a well-structured area of occupation: built spaces, passage areas, waste zones. Settlements of tell type are located in the river valleys –on erosion remnants, alluvial bars or small islands, at the border of the valleys– on edges or prominences of Pleistocene terraces, lower Holocene terraces, and banks of lakes. This study integrates data on the geographical position, the morphological background, and the general stratigraphy of these important settlements. The correlation of the spatial distribution with the geomorphological units of each area of evolution creates an image of the natural landscape in which they occurred. The sedimentological researches achieved in the floodplain area of Balta Ialomiței showed important changes in the alluvial activity of Danube, after the Chalcolithic period (ca. 6500 - 6000 BP), to Iron Age and Middle Ages. The micromorphological analysis, consisting in thin section interpretation, at the microscopic scale, of sediments and soils in an undisturbed state, allowed the interpretation of the identified sedimentary facies, in terms of mode of formation and anthropic activities. Our studied cases reflect some distinct situations, correlating either with the geomorphological background or with the vertical development, the presence of delimiting structures and the internal organization. The characteristics of tells from this area bring significant information about the human habitation of Lower Danube in Prehistory.

Keywords: chalcolithic, micromorphology, Romania, sedimentology, tell settlements

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653 Influence of Internal Topologies on Components Produced by Selective Laser Melting: Numerical Analysis

Authors: C. Malça, P. Gonçalves, N. Alves, A. Mateus

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Regardless of the manufacturing process used, subtractive or additive, material, purpose and application, produced components are conventionally solid mass with more or less complex shape depending on the production technology selected. Aspects such as reducing the weight of components, associated with the low volume of material required and the almost non-existent material waste, speed and flexibility of production and, primarily, a high mechanical strength combined with high structural performance, are competitive advantages in any industrial sector, from automotive, molds, aviation, aerospace, construction, pharmaceuticals, medicine and more recently in human tissue engineering. Such features, properties and functionalities are attained in metal components produced using the additive technique of Rapid Prototyping from metal powders commonly known as Selective Laser Melting (SLM), with optimized internal topologies and varying densities. In order to produce components with high strength and high structural and functional performance, regardless of the type of application, three different internal topologies were developed and analyzed using numerical computational tools. The developed topologies were numerically submitted to mechanical compression and four point bending testing. Finite Element Analysis results demonstrate how different internal topologies can contribute to improve mechanical properties, even with a high degree of porosity relatively to fully dense components. Results are very promising not only from the point of view of mechanical resistance, but especially through the achievement of considerable variation in density without loss of structural and functional high performance.

Keywords: additive manufacturing, internal topologies, porosity, rapid prototyping, selective laser melting

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652 Sun-Driven Evaporation Enhanced Forward Osmosis Process for Application in Wastewater Treatment and Pure Water Regeneration

Authors: Dina Magdy Abdo, Ayat N. El-Shazly, Hamdy Maamoun Abdel-Ghafar, E. A. Abdel-Aal

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Forward osmosis (FO) is one of the important processes during the wastewater treatment system for environmental remediation and fresh water regeneration. Both Egypt and China are troubled by over millions of tons of wastewater every year, including domestic and industrial wastewater. However, traditional FO process in wastewater treatment usually suffers low efficiency and high energy consumption because of the continuously diluted draw solution. An additional concentration process is necessary to keep running of FO separation, causing energy waste. Based on the previous study on photothermal membrane, a sun-driven evaporation process is integrated into the draw solution side of FO system. During the sun-driven evaporation, not only the draw solution can be concentrated to maintain a stable and sustainable FO system, but fresh water can be directly separated for regeneration. Solar energy is the ultimate energy source of everything we have on Earth and is, without any doubt, the most renewable and sustainable energy source available to us. Additionally, the FO membrane process is rationally designed to limit the concentration polarization and fouling. The FO membrane’s structure and surface property will be further optimized by the adjustment of the doping ratio of controllable nano-materials, membrane formation conditions, and selection of functional groups. A novel kind of nano-composite functional separation membrane with bi-interception layers and high hydrophilicity will be developed for the application in wastewater treatment. So, herein we aim to design a new wastewater treatment system include forward osmosis with high-efficiency energy recovery via the integration of photothermal membrane.

Keywords: forword, membrane, solar, water treatment

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651 Effective Water Purification by Impregnated Carbon Nanotubes

Authors: Raviteja Chintala

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Water shortage in many areas of the world have predominantly increased the demand for efficient methods involved in the production of drinking water, So purification of water invoking cost effective and efficient methods is a challenging field of research. In this regard, Reverse osmosis membrane desalination of both seawater and inland brackish water is currently being deployed in various locations around the world. In the present work an attempt is made to integrate these existing technologies with novel method, Wherein carbon nanotubes at the lab scale are prepared which further replace activated carbon tubes being used traditionally. This has proven to enhance the efficiency of the water filter, Effectively neutralising most of the organic impurities. Furthermore, This ensures the reduction in TDS. Carbon nanotubes have wide range in scope of applications such as composite reinforcements, Field emitters, Sensors, Energy storage and energy conversion devices and catalysts support phases, Because of their unusual mechanical, Electrical, Thermal and structural properties. In particular, The large specific surface area, as well as the high chemical and thermal stability, Makes carbon nanotube an attractive adsorbent in waste water treatment. Carbon nanotubes are effective in eliminating these harmful media from water as an adsorbent. In this work, Candle soot method has been incorporated for the preparation of carbon nanotubes and mixed with activated charcoal in different compositions. The effect of composition change is monitored by using TDS measuring meter. As the composition of Nano carbon increases, The TDS of the water gradually decreases. In order to enhance the life time for carbon filter, Nano tubes are provided with larger surface area.

Keywords: TDS (Total Dissolved Solids), carbon nanotubes, water, candle soot

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650 Biosorption of Methylene Blue and Acid Red-88 from Wastewater by Using Cypress Cones

Authors: Onur Yel

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This study represents the removal of harmful dye substances from wastewaters by using waste and cheap adsorbents. Rapid population growth and industrialization occasion anthropogenic pollution which gives irreversible damage to the environment. One of the ways in which water pollution occurs is caused by the release of the dyestuffs in the textile industry. The release of dyestuffs to the environment directly damages the living creatures that have acquired water habitat. Especially, wastewater cannot be used for nutritional purposes. In addition, some adsorbents have mutagenic and/or carcinogenic effects. By blocking photosynthesis, it hinders the inhibition of photosynthetic bacteria in the water, which damages the ecological balance and also causes the formation of malodorous compounds. Moreover, the lack of oxygen can pose a serious danger to the lives of other living organisms that need oxygen. In recent years, some physical and chemical methods are preferred for the removal of dyestuffs. However, the utilization of these methods is expensive. For this reason, the availability of new and cheap adsorbents becomes the more significant issue. In this study, an investigation of various variables on the removal of Methylene Blue and Acid Red-88 dyestuffs from wastewaters by the usage of pulverized cypress cones has been carried out. Thus, various masses of absorbent (0.1-0.25-0.5-1-2-4-5 grams) are used in 50, 100, 150, 200, 300 ppm concentrations of Methylene Blue and Acid Red-88 dyestuffs’ solutions, and with a variety of the interaction time (0.25-0.5-1-2-4-5 hours). The mixtures were centrifuged and the absorbance of the filtrates was measured on a UV spectrophotometer to determine their remaining concentrations. In the study, the highest removal ratio of Acid Red-88 dyestuff was found to be 81% at 200 ppm of dyestuff with 2 grams of adsorbent at 300 minutes. For Methylene Blue experiments, the removal percentage was found as 98% where 2 grams of adsorbent is used in 200 ppm dyestuff solution at 120 minutes of interaction.

Keywords: acid red-88, biosorption, methylene blue, cypress cones, water pollution

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649 GIS Model for Sanitary Landfill Site Selection Based on Geotechnical Parameters

Authors: Hecson Christian, Joel Macwan

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Landfill site selection in an urban area is a critical issue in the planning process. With the growth of the urbanization, it has a mammoth impact on the economy, ecology, and environmental health of the region. Outsized amount of wastes are produced and the problem gets soared every day. Hence, selection of ideal site for sanitary landfill is a challenge for urban planners and solid waste managers. Disposal site is a function of many parameters. Among all, Geotechnical parameters are very vital as the same is related to surrounding open land. Moreover, the accessible safe and acceptable land is also scarce. Therefore, in this paper geotechnical parameters are used to develop a GIS model to identify an ideal location for landfill purpose. Metropolitan city of Surat is highly populated and fastest growing urban area in India. The research objectives are to conduct field experiments to collect data and to transfer the facts in GIS platform to evolve a model, to find ideal location. Planners’ preferences were obtained to use analytical hierarchical process (AHP) to find weights of each parameter. Integration of GIS and Multi-Criteria Decision Analysis (MCDA) techniques are applied to improve decision-making. It augments an environment for transformation and combination of geographical data and planners’ preferences. GIS performs deterministic overlay and buffer operations. MCDA methods evaluate alternatives based on the decision makers’ subjective values and priorities. Research results have shown many alternative locations. Economic analysis of selected site from actual operations point of view is not included in this research.

Keywords: GIS, AHP, MCDA, Geo-technical

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648 The Concept of Birthday: A Theoretical, Historical, and Social Overview, in Judaism and Other Cultures

Authors: Orly Redlich

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In the age of social distance, which has been added to an individual and competitive worldview, it has become important to find a way to promote closeness and personal touch. The sense of social belonging and the existence of positive interaction with others have recently become a considerable necessity. Therefore, this theoretical paper will review one of the familiar and common concepts among different cultures around the world – birthday. This paper has a theoretical contribution that deepens the understanding of the birthday concept. Birthday rituals are historical and universal events, which noted since the prehistoric eras. In ancient history, birthday rituals were solely reserved for kings and nobility members, but over the years, birthday celebrations have evolved into a worldwide tradition. Some of the familiar birthday customs and symbols are currently common among most cultures, while some cultures have adopted for themselves unique birthday customs, which characterized their values and traditions. The birthday concept has a unique significance in Judaism as well, historically, religiously, and socially: It is considered as a lucky day and a private holiday for the celebrant. Therefore, the present paper reviews diverse birthday customs around the world in different cultures, including Judaism, and marks important birthdays throughout history. The paper also describes how the concept of birthday appears over the years in songs, novels, and art, and presents quotes from distinguished sages. The theoretical review suggests that birthday has a special meaning as a time-mark in the cycle of life, and as a socialization means in human development. Moreover, the birthday serves as a symbol of belonging and group cohesiveness, a day in which the celebrant's sense of belonging and sense of importance are strengthened and nurtured. Thus, the reappearance of these elements in a family or group interaction during the birthday ceremony allows the celebrant to absorb positive impressions about himself. In view of the extensive theoretical review, it seems that the unique importance of birthdays can serve as the foundation for intervention programs that may affect the participants’ sense of belonging and empowerment. In the group aspect, perhaps it can also yield therapeutic factors within a group. Concrete recommendations are presented at the end of the paper.

Keywords: birthday, universal events, positive interaction, group cohesiveness, rituals

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647 Multi-Objective Discrete Optimization of External Thermal Insulation Composite Systems in Terms of Thermal and Embodied Energy Performance

Authors: Berfin Yildiz

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These days, increasing global warming effects, limited amount of energy resources, etc., necessitates the awareness that must be present in every profession group. The architecture and construction sectors are responsible for both the embodied and operational energy of the materials. This responsibility has led designers to seek alternative solutions for energy-efficient material selection. The choice of energy-efficient material requires consideration of the entire life cycle, including the building's production, use, and disposal energy. The aim of this study is to investigate the method of material selection of external thermal insulation composite systems (ETICS). Embodied and in-use energy values of material alternatives were used for the evaluation in this study. The operational energy is calculated according to the u-value calculation method defined in the TS 825 (Thermal Insulation Requirements) standard for Turkey, and the embodied energy is calculated based on the manufacturer's Energy Performance Declaration (EPD). ETICS consists of a wall, adhesive, insulation, lining, mechanical, mesh, and exterior finishing materials. In this study, lining, mechanical, and mesh materials were ignored because EPD documents could not be obtained. The material selection problem is designed as a hypothetical volume area (5x5x3m) and defined as a multi-objective discrete optimization problem for external thermal insulation composite systems. Defining the problem as a discrete optimization problem is important in order to choose between materials of various thicknesses and sizes. Since production and use energy values, which are determined as optimization objectives in the study, are often conflicting values, material selection is defined as a multi-objective optimization problem, and it is aimed to obtain many solution alternatives by using Hypervolume (HypE) algorithm. The enrollment process started with 100 individuals and continued for 50 generations. According to the obtained results, it was observed that autoclaved aerated concrete and Ponce block as wall material, glass wool, as insulation material gave better results.

Keywords: embodied energy, multi-objective discrete optimization, performative design, thermal insulation

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646 A Multi-Templated Fe-Ni-Cu Ion Imprinted Polymer for the Selective and Simultaneous Removal of Toxic Metallic Ions from Wastewater

Authors: Morlu Stevens, Bareki Batlokwa

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The use of treated wastewater is widely employed to compensate for the scarcity of safe and uncontaminated freshwater. However, the existence of toxic heavy metal ions in the wastewater pose a health hazard to animals and the environment, hence, the importance for an effective technique to tackle the challenge. A multi-templated ion imprinted sorbent (Fe,Ni,Cu-IIP) for the simultaneous removal of heavy metal ions from waste water was synthesised employing molecular imprinting technology (MIT) via thermal free radical bulk polymerization technique. Methacrylic acid (MAA) was employed as the functional monomer, and ethylene glycol dimethylacrylate (EGDMA) as cross-linking agent, azobisisobutyronitrile (AIBN) as the initiator, Fe, Ni, Cu ions as template ions, and 1,10-phenanthroline as the complexing agent. The template ions were exhaustively washed off the synthesized polymer by solvent extraction in several washing steps, while periodically increasing solvent (HCl) concentration from 1.0 M to 10.0 M. The physical and chemical properties of the sorbents were investigated using Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD) and Atomic Force Microscopy (AFM) were employed. Optimization of operational parameters such as time, pH and sorbent dosage to evaluate the effectiveness of sorbents were investigated and found to be 15 min, 7.5 and 666.7 mg/L respectively. Selectivity of ion-imprinted polymers and competitive sorption studies between the template and similar ions were carried out and showed good selectivity towards the targeted metal ion by removing 90% - 98% of the templated ions as compared to 58% - 62% of similar ions. The sorbents were further applied for the selective removal of Fe, Ni and Cu from real wastewater samples and recoveries of 92.14 ± 0.16% - 106.09 ± 0.17% and linearities of R2 = 0.9993 - R2 = 0.9997 were achieved.

Keywords: ion imprinting, ion imprinted polymers, heavy metals, wastewater

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645 Fertigation Use in Agriculture and Biosorption of Residual Nitrogen by Soil Microorganisms

Authors: Irina Mikajlo, Jakub Elbl, Helena Dvořáčková, Antonín Kintl, Jindřich Kynický, Martin Brtnický, Jaroslav Záhora

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Present work deals with the possible use of fertigation in agriculture and its impact on the availability of mineral nitrogen (Nmin) in topsoil and subsoil horizons. The aim of the present study is to demonstrate the effect of the organic matter presence in fertigation on microbial transformation and availability of mineral nitrogen forms. The main investigation reason is the potential use of pre-treated waste water, as a source of organic carbon (Corg) and residual nutrients (Nmin) for fertigation. Laboratory experiment has been conducted to demonstrate the effect of the arable land fertilization method on the Nmin availability in different depths of the soil with the usage of model experimental containers filled with soil from topsoil and podsoil horizons that were taken from the precise area. Tufted hairgrass (Deschampsia caespitosa) has been chosen as a model plant. The water source protection zone Brezova nad Svitavou has been a research area where significant underground reservoirs of drinking water of the highest quality are located. From the second half of the last century local sources of drinking water show nitrogenous compounds increase that get here almost only from arable lands. Therefore, an attention of the following text focuses on the fate of mineral nitrogen in the complex plant-soil. Research results show that the fertigation application with Corg in a combination with mineral fertilizer can reduce the amount of Nmin leached from topsoil horizon of agricultural soils. In addition, some plants biomass production reduce may occur.

Keywords: fertigation, fertilizers, mineral nitrogen, soil microorganisms

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644 The Role of Heat Pumps in the Decarbonization of European Regions

Authors: Domenico M. Mongelli, Michele De Carli, Laura Carnieletto, Filippo Busato

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Europe's dependence on imported fossil fuels has been particularly highlighted by the Russian invasion of Ukraine. Limiting this dependency with a massive replacement of fossil fuel boilers with heat pumps for building heating is the goal of this work. Therefore, with the aim of diversifying energy sources and evaluating the potential use of heat pump technologies for residential buildings with a view to decarbonization, the quantitative reduction in the consumption of fossil fuels was investigated in all regions of Europe through the use of heat pumps. First, a general overview of energy consumption in buildings in Europe has been assessed. The consumption of buildings has been addressed to the different uses (heating, cooling, DHW, etc.) as well as the different sources (natural gas, oil, biomass, etc.). The analysis has been done in order to provide a baseline at the European level on the current consumptions and future consumptions, with a particular interest in the future increase of cooling. A database was therefore created on the distribution of residential energy consumption linked to air conditioning among the various energy carriers (electricity, waste heat, gas, solid fossil fuels, liquid fossil fuels, and renewable sources) for each region in Europe. Subsequently, the energy profiles of various European cities representative of the different climates are analyzed in order to evaluate, in each European climatic region, which energy coverage can be provided by heat pumps in replacement of natural gas and solid and liquid fossil fuels for air conditioning of the buildings, also carrying out the environmental and economic assessments for this energy transition operation. This work aims to make an innovative contribution to the evaluation of the potential for introducing heat pump technology for decarbonization in the air conditioning of buildings in all climates of the different European regions.

Keywords: heat pumps, heating, decarbonization, energy policies

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643 Economics of Fish-Plantain Integrated Farm Enterprise in Southern Nigeria

Authors: S. O. Obasa, J. A. Soaga, O. I. Afolabi, N. A. Bamidele, O. E. Babalola

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Attempt to improve the income of the rural population is a welcome development in Nigeria. Integrated fish-crop farming has been suggested as a means of raising farm income, reducing wastage and mitigating the risk component in production through the complementarity gain. A feeding trial was carried out to investigate the replacement of maize with fermented unripe plantain (Musa paradisiaca) peel meal in the diet of Nile tilapia, Oreochromis niloticus. The economics of the integrated enterprise was assessed using budgetary analysis techniques. The analysis incorporated the material and labour costs as well as the returns from sale of matured fish and plantain. A total of 60 fingerlings of Nile tilapia (1.70±0.1 g) were stocked at 10 per plastic tank. Two iso-nitrogenous diets containing 35% crude protein in which maize meal was replaced by fermented unripe plantain peel meal at 0% (FUP0/Control diet), and 100% (FUP100) were formulated and prepared. The fingerlings were fed at 5% body weight per day for 56 days. Lowest feed conversion ratio of 1.39 in fish fed diet FUP100 was not significantly different (P > 0.05) from the highest 1.42 of fish fed the Control diet. The highest percentage profit of 88.85% in fish fed diet FUP100 was significantly higher than 66.68% in fish fed diet FUP0, while the profit index of 1.89 in fish fed diet FUP100 was significantly different from 1.67 in fish fed diet FUP0. Therefore, fermented unripe plantain peel meal can completely replace maize in the diet of O. niloticus fingerlings. Profitability assessment shows that the net income from the integration was ₦ 463,000 per hectare and the integration resulted to an increase of ₦ 87,750.00 representing a 12.2% increase than in separate production.

Keywords: fish-crop, income, Nile tilapia, waste management

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642 Tinder as a Queer Identity Building Tool: An Ethnographic Study of How Dating Apps Are Used as Identity Markers among Queer Women in Bologna, Italy

Authors: Lovis Ingrid Hakala

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This paper provides an example of how the dating app Tinder can be used as a tool in queer research and what the use of the app among lesbians can tell us about the production of particular kinds of lesbian identities paired with technology. This study seeks to understand the ways in which the app is understood by lesbian women and how it is brought into their understandings of what being a lesbian means. Dating apps are becoming increasingly common as tools for meeting a potential partner and research has shown how these apps gain new meaning depending on the context. This paper will show both how Tinder has gained a particular meaning in a lesbian context in Bologna, and also how the use of Tinder produces specific ideas of what lesbians are and how they act. While doing ethnographic fieldwork among young lesbians (20-30 years old) in Bologna in the autumn of 2017, as a part of the research methodology, Tinder was used together with interviews and participant observation. By signing up on Tinder and contacting potential informants on the app the aim was to reach women who were not necessarily involved in the queer activist spaces in the city and who might thus provide a different perspective than their activist counterparts. Using Tinder as a tool in research proved to be a useful methodology both when it came to contacting potential informants as well as in gaining a better understanding for queer identity building, and the role Tinder played in defining lesbianism in Bologna. The app itself was often deemed useless, and informants often complained about the lack of women on the app who had their profile showing an interest in women. Apart from being away for the interlocutors to get in touch with potential romantic or sexual partners, the app did provide a concrete object around which to define particular lesbian behavior. Lesbians were described to be slow at answering and not being very eager to meet. This placed lesbian women, in contrast to gay men who were seen as doing the opposite, using dating apps a lot and be quick to propose meetings. Tinder among lesbians in Bologna thus proved to have a dual function as both a way of creating connections between queer women but also as a tool to define what a lesbian is. This paper provides insight into the ways in which dating apps provides a community and identity building function and how a certain behavior on said apps can be a part of defining identity. This work stands out among other literature on dating apps since it does not only focus on the methodological aspects of using Tinder as a tool in research but also provides an insight in how the way in which individuals use the app comes to add to an understanding of what a lesbian is.

Keywords: dating apps, identity, Italy, lesbian, queer

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641 Multi-Index Performance Investigation of Rubberized Reclaimed Asphalt Mixture

Authors: Ling Xu, Giuseppe Loprencipe, Antonio D'Andrea

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Asphalt pavement with recycled and sustainable materials has become the most commonly adopted strategy for road construction, including reclaimed asphalt pavement (RAP) and crumb rubber (CR) from waste tires. However, the adhesion and cohesion characteristics of rubberized reclaimed asphalt pavement were still ambiguous, resulting in deteriorated adhesion behavior and life performance. This research investigated the effect of bonding characteristics on rutting resistance and moisture susceptibility of rubberized reclaimed asphalt pavement in terms of two RAP sources with different oxidation levels and two tire rubber with different particle sizes. Firstly, the binder bond strength (BBS) test and bonding failure distinguishment were conducted to analyze the surface behaviors of binder-aggregate interaction. Then, the compatibility and penetration grade of rubberized RAP binder were evaluated by rotational viscosity test and penetration test, respectively. Hamburg wheel track (HWT) test with high-temperature viscoelastic deformation analysis was adopted, which illustrated the rutting resistance. Additionally, a water boiling test was employed to evaluate the moisture susceptibility of the mixture and the texture features were characterized with the statistical parameters of image colors. Finally, the colloid structure model of rubberized RAP binder with surface interaction was proposed, and statistical analysis was established to release the correlation among various indexes. This study concluded that the gel-phase colloid structure and molecular diffusion of the free light fraction would affect the surface interpretation with aggregate, determining the bonding characteristic of rubberized RAP asphalt.

Keywords: bonding characteristics, reclaimed asphalt pavement, rubberized asphalt, sustainable material

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640 Synthesis and Characterization of CNPs Coated Carbon Nanorods for Cd2+ Ion Adsorption from Industrial Waste Water and Reusable for Latent Fingerprint Detection

Authors: Bienvenu Gael Fouda Mbanga

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This study reports a new approach of preparation of carbon nanoparticles coated cerium oxide nanorods (CNPs/CeONRs) nanocomposite and reusing the spent adsorbent of Cd2+- CNPs/CeONRs nanocomposite for latent fingerprint detection (LFP) after removing Cd2+ ions from aqueous solution. CNPs/CeONRs nanocomposite was prepared by using CNPs and CeONRs with adsorption processes. The prepared nanocomposite was then characterized by using UV-visible spectroscopy (UV-visible), Fourier transforms infrared spectroscopy (FTIR), X-ray diffraction pattern (XRD), scanning electron microscope (SEM), Transmission electron microscopy (TEM), Energy-dispersive X-ray spectroscopy (EDS), Zeta potential, X-ray photoelectron spectroscopy (XPS). The average size of the CNPs was 7.84nm. The synthesized CNPs/CeONRs nanocomposite has proven to be a good adsorbent for Cd2+ removal from water with optimum pH 8, dosage 0. 5 g / L. The results were best described by the Langmuir model, which indicated a linear fit (R2 = 0.8539-0.9969). The adsorption capacity of CNPs/CeONRs nanocomposite showed the best removal of Cd2+ ions with qm = (32.28-59.92 mg/g), when compared to previous reports. This adsorption followed pseudo-second order kinetics and intra particle diffusion processes. ∆G and ∆H values indicated spontaneity at high temperature (40oC) and the endothermic nature of the adsorption process. CNPs/CeONRs nanocomposite therefore showed potential as an effective adsorbent. Furthermore, the metal loaded on the adsorbent Cd2+- CNPs/CeONRs has proven to be sensitive and selective for LFP detection on various porous substrates. Hence Cd2+-CNPs/CeONRs nanocomposite can be reused as a good fingerprint labelling agent in LFP detection so as to avoid secondary environmental pollution by disposal of the spent adsorbent.

Keywords: Cd2+-CNPs/CeONRs nanocomposite, cadmium adsorption, isotherm, kinetics, thermodynamics, reusable for latent fingerprint detection

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639 Estimation of Dynamic Characteristics of a Middle Rise Steel Reinforced Concrete Building Using Long-Term

Authors: Fumiya Sugino, Naohiro Nakamura, Yuji Miyazu

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In earthquake resistant design of buildings, evaluation of vibration characteristics is important. In recent years, due to the increment of super high-rise buildings, the evaluation of response is important for not only the first mode but also higher modes. The knowledge of vibration characteristics in buildings is mostly limited to the first mode and the knowledge of higher modes is still insufficient. In this paper, using earthquake observation records of a SRC building by applying frequency filter to ARX model, characteristics of first and second modes were studied. First, we studied the change of the eigen frequency and the damping ratio during the 3.11 earthquake. The eigen frequency gradually decreases from the time of earthquake occurrence, and it is almost stable after about 150 seconds have passed. At this time, the decreasing rates of the 1st and 2nd eigen frequencies are both about 0.7. Although the damping ratio has more large error than the eigen frequency, both the 1st and 2nd damping ratio are 3 to 5%. Also, there is a strong correlation between the 1st and 2nd eigen frequency, and the regression line is y=3.17x. In the damping ratio, the regression line is y=0.90x. Therefore 1st and 2nd damping ratios are approximately the same degree. Next, we study the eigen frequency and damping ratio from 1998 after 3.11 earthquakes, the final year is 2014. In all the considered earthquakes, they are connected in order of occurrence respectively. The eigen frequency slowly declined from immediately after completion, and tend to stabilize after several years. Although it has declined greatly after the 3.11 earthquake. Both the decresing rate of the 1st and 2nd eigen frequencies until about 7 years later are about 0.8. For the damping ratio, both the 1st and 2nd are about 1 to 6%. After the 3.11 earthquake, the 1st increases by about 1% and the 2nd increases by less than 1%. For the eigen frequency, there is a strong correlation between the 1st and 2nd, and the regression line is y=3.17x. For the damping ratio, the regression line is y=1.01x. Therefore, it can be said that the 1st and 2nd damping ratio is approximately the same degree. Based on the above results, changes in eigen frequency and damping ratio are summarized as follows. In the long-term study of the eigen frequency, both the 1st and 2nd gradually declined from immediately after completion, and tended to stabilize after a few years. Further it declined after the 3.11 earthquake. In addition, there is a strong correlation between the 1st and 2nd, and the declining time and the decreasing rate are the same degree. In the long-term study of the damping ratio, both the 1st and 2nd are about 1 to 6%. After the 3.11 earthquake, the 1st increases by about 1%, the 2nd increases by less than 1%. Also, the 1st and 2nd are approximately the same degree.

Keywords: eigenfrequency, damping ratio, ARX model, earthquake observation records

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638 The Importance of Storage Period on Biogas Potential of Cattle Manure

Authors: Seongwon Im, Jimin Kim, Kyeongcheol Kim, Dong-Hoon Kim

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Cattle manure (CM) produced from farmhas been utilized to soils for increasing crop production owing to high nutrients content and effective microorganisms. Some cities with the concentrated activity of livestock industry have suffered from environmental problems, such as odorous gas emissions and soil and water pollution, caused by excessive use of compost. As an alternative option, the anaerobic digestion (AD) process can be utilized, which can reduce the volume of organic waste but also produce energy. According to Korea-Ministry of Trade, Industry, and Energy (KMTIE), the energy potential of CM via biogas production was estimated to be 0.8 million TOE per year, which is higher than that of other organic wastes. However, limited energy is recovered since useful organic matter, capable of converting to biogas, may be degraded during the long storage period (1-6 months).In this study, the effect of storage period on biogas potential of CM was investigated. Compared to fresh CM (VS 14±1 g/L, COD 205±5 g/L, TKN 7.4±0.8 g/L, NH4+-N 1.5±0.1), old CM has higher organic (35-37%) and nitrogen content (50-100%) due to the drying process during storage. After stabilization period, biogas potential of 0.09 L CH4/g VS was obtained in R1 (old CM supplement) at HRT of 150-100 d, and it was decreased further to 0.06 L CH4/g VS at HRT of 80 d. The drop of pH and organic acids accumulation were not observed during the whole operation of R1. Ammonia stripping and pretreatment of CM were found to be not effective to increase CH4 yield. On the other hand, a sudden increase of biogas potential to 0.19-0.22 L CH4/g VS was achieved in R2 after changing feedstock to fresh CM. The expected reason for the low biogas potential of old CM might be related with the composition of organic matters in CM. Easily biodegradable organic matters in the fresh CM were contained in high concentration, butthey were removed by microorganisms during storing CM in a farm, resulting low biogas yield. This study implies that fresh storage is important to make AD process applicable for CM.

Keywords: storage period, cattle manure, biogas potential, microbial analysis

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637 Identification of Architectural Design Error Risk Factors in Construction Projects Using IDEF0 Technique

Authors: Sahar Tabarroki, Ahad Nazari

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The design process is one of the most key project processes in the construction industry. Although architects have the responsibility to produce complete, accurate, and coordinated documents, architectural design is accompanied by many errors. A design error occurs when the constraints and requirements of the design are not satisfied. Errors are potentially costly and time-consuming to correct if not caught early during the design phase, and they become expensive in either construction documents or in the construction phase. The aim of this research is to identify the risk factors of architectural design errors, so identification of risks is necessary. First, a literature review in the design process was conducted and then a questionnaire was designed to identify the risks and risk factors. The questions in the form of the questionnaire were based on the “similar service description of study and supervision of architectural works” published by “Vice Presidency of Strategic Planning & Supervision of I.R. Iran” as the base of architects’ tasks. Second, the top 10 risks of architectural activities were identified. To determine the positions of possible causes of risks with respect to architectural activities, these activities were located in a design process modeled by the IDEF0 technique. The research was carried out by choosing a case study, checking the design drawings, interviewing its architect and client, and providing a checklist in order to identify the concrete examples of architectural design errors. The results revealed that activities such as “defining the current and future requirements of the project”, “studies and space planning,” and “time and cost estimation of suggested solution” has a higher error risk than others. Moreover, the most important causes include “unclear goals of a client”, “time force by a client”, and “lack of knowledge of architects about the requirements of end-users”. For error detecting in the case study, lack of criteria, standards and design criteria, and lack of coordination among them, was a barrier, anyway, “lack of coordination between architectural design and electrical and mechanical facility”, “violation of the standard dimensions and sizes in space designing”, “design omissions” were identified as the most important design errors.

Keywords: architectural design, design error, risk management, risk factor

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636 Photocatalytic Degradation of Methylene Blue Dye Using Cuprous Oxide/Graphene Nanocomposite

Authors: Bekan Bogale, Tsegaye Girma Asere, Tilahun Yai, Fekadu Melak

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Aims: To study photocatalytic degradation of methylene blue dye on cuprous oxide/graphene nanocomposite. Background: Cuprous oxide (Cu2O) nanoparticles are among the metal oxides that demonstrated photocatalytic activity. However, the stability of Cu2O nanoparticles due to the fast recombination rate of electron/hole pairs remains a significant challenge in their photocatalytic applications. This, in turn, leads to mismatching of the effective bandgap separation, tending to reduce the photocatalytic activity of the desired organic waste (MB). To overcome these limitations, graphene has been combined with cuprous oxides, resulting in cuprous oxide/graphene nanocomposite as a promising photocatalyst. Objective: In this study, Cu2O/graphene nanocomposite was synthesized and evaluated for its photocatalytic performance of methylene blue (MB) dye degradation. Method: Cu2O/graphene nanocomposites were synthesized from graphite powder and copper nitrate using the facile sol-gel method. Batch experiments have been conducted to assess the applications of the nanocomposites for MB degradation. Parameters such as contact time, catalyst dosage, and pH of the solution were optimized for maximum MB degradation. The prepared nanocomposites were characterized by using UV-Vis, FTIR, XRD, and SEM. The photocatalytic performance of Cu2O/graphene nanocomposites was compared against Cu2O nanoparticles for cationic MB dye degradation. Results: Cu2O/graphene nanocomposite exhibits higher photocatalytic activity for MB degradation (with a degradation efficiency of 94%) than pure Cu2O nanoparticles (67%). This has been accomplished after 180 min of irradiation under visible light. The kinetics of MB degradation by Cu2O/graphene composites can be demonstrated by the second-order kinetic model. The synthesized nanocomposite can be used for more than three cycles of photocatalytic MB degradation. Conclusion: This work indicated new insights into Cu2O/graphene nanocomposite as high-performance in photocatalysis to degrade MB, playing a great role in environmental protection in relation to MB dye.

Keywords: methylene blue, photocatalysis, cuprous oxide, graphene nanocomposite

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635 Ecological impacts of Cage Farming: A Case Study of Lake Victoria, Kenya

Authors: Mercy Chepkirui, Reuben Omondi, Paul Orina, Albert Getabu, Lewis Sitoki, Jonathan Munguti

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Globally, the decline in capture fisheries as a result of the growing population and increasing awareness of the nutritional benefits of white meat has led to the development of aquaculture. This is anticipated to meet the increasing call for more food for the human population, which is likely to increase further by 2050. Statistics showed that more than 50% of the global future fish diet will come from aquaculture. Aquaculture began commercializing some decades ago; this is accredited to technological advancement from traditional to modern cultural systems, including cage farming. Cage farming technology has been rapidly growing since its inception in Lake Victoria, Kenya. Currently, over 6,000 cages have been set up in Kenyan waters, and this offers an excellent opportunity for recognition of Kenya’s government tactic to eliminate food insecurity and malnutrition, create employment and promote a Blue Economy. However, being an open farming enterprise is likely to emit large bulk of waste hence altering the ecosystem integrity of the lake. This is through increased chlorophyll-a pigments, alteration of the plankton community, macroinvertebrates, fish genetic pollution, transmission of fish diseases and pathogens. Cage farming further increases the nutrient loads leading to the production of harmful algal blooms, thus negatively affecting aquatic and human life. Despite the ecological transformation, cage farming provides a platform for the achievement of the Sustainable Development Goals of 2030, especially the achievement of food security and nutrition. Therefore, there is a need for Integrated Multitrophic Aquaculture as part of Blue Transformation for ecosystem monitoring.

Keywords: aquaculture, ecosystem, blue economy, food security

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634 Geological, Engineering Geological, and Hydrogeological Characteristics of the Knowledge Economic City, Al Madinah Al Munawarah, KSA

Authors: Mutasim A. M. Ez Eldin, Tareq Saeid Al Zahrani, Gabel Zamil Al-Barakati, Ibrahim Mohamed AlHarthi, Marwan Mohamed Al Saikhan, Waleed Abdel Aziz Al Aklouk, Waheed Mohamed Saeid Ba Amer

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The Knowledge Economic City (KEC) of Al Madinah Al Munawarah is one of the major projects and represents a cornerstone for the new development activities for Al Madinah. The study area contains different geological units dominated by basalt and overlain by surface deposits. The surface soils vary in thickness and can be classified into well-graded SAND with silt and gravel (SW-SM), silty SAND with gravel (SM), silty GRAVEL with sand (GM), and sandy SILTY clay (CL-ML). The subsurface soil obtained from the drilled boreholes can be classified into poorly graded GRAVEL (GP), well-graded GRAVEL with sand (GW), poorly graded GRAVEL with silt (GP-GM), silty CLAYEY gravel with sand (GC-GM), silty SAND with gravel (SM), silt with SAND (ML), and silty CLAY with sand (CL-ML), sandy lean CLAY (CL), and lean CLAY (CL). The relative density of the deposit and the different gravel sizes intercalated with the soil influenced the Standard Penetration Tests (SPT) values. The SPT N values are high and approach refusal even at shallow depths. The shallow refusal depth (0.10 to 0.90m) of the Dynamic Cone Penetration Test (DCPT) was observed. Generally, the soil can be described as inactive with low plasticity and dense to very dense consistency. The basalt of the KEC site is characterized by slightly (W2) to moderately (W3) weathering, their strength ranges from moderate (S4) to very strong (S2), and the Rock Quality Designation (RQD) ranges from very poor (R5) to excellent (R1). The engineering geological map of the KEC characterized the geoengineering properties of the soil and rock materials and classified them into many zones. The high sulphate (SO₄²⁻) and chloride (Cl⁻) contents in groundwater call for protective measures for foundation concrete. The current study revealed that geohazard(s) mitigation measures concerning floods, volcanic eruptions, and earthquakes should be taken into consideration.

Keywords: engineering geology, KEC, petrographic description, rock and soil investigations

Procedia PDF Downloads 75