Search results for: chemical oxygen demand (COD)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8289

Search results for: chemical oxygen demand (COD)

1629 Volume Estimation of Trees: An Exploratory Study on Pterocarpus erinaceus Logging Operations within Forest Transition and Savannah Ecological Zones of Ghana

Authors: Albert Kwabena Osei Konadu

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Pterocarpus erinaceus, also known as Rosewood, is tropical wood, endemic in forest savannah transition zones within the middle and northern portion of Ghana. Its economic viability has made it increasingly popular and in high demand, leading to widespread conservation concerns. Ghana’s forest resource management regime for these ecozones is mainly on conservation and very little on resource utilization. Consequently, commercial logging management standards are at teething stage and not fully developed, leading to a deficiency in the monitoring of logging operations and quantification of harvested trees volumes. Tree information form (TIF); a volume estimation and tracking regime, has proven to be an effective, sustainable management tool for regulating timber resource extraction in the high forest zones of the country. This work aims to generate TIF that can track and capture requisite parameters to accurately estimate the volume of harvested rosewood within forest savannah transition zones. Tree information forms were created on three scenarios of individual billets, stacked billets and conveying vessel basis. These TIFs were field-tested to deduce the most viable option for the tracking and estimation of harvested volumes of rosewood using the smallian and cubic volume estimation formula. Overall, four districts were covered with individual billets, stacked billets and conveying vessel scenarios registering mean volumes of 25.83m3,45.08m3 and 32.6m3, respectively. These adduced volumes were validated by benchmarking to assigned volumes of the Forestry Commission of Ghana and known standard volumes of conveying vessels. The results did indicate an underestimation of extracted volumes under the quotas regime, a situation that could lead to unintended overexploitation of the species. The research revealed conveying vessels route is the most viable volume estimation and tracking regime for the sustainable management of the Pterocarpous erinaceus species as it provided a more practical volume estimate and data extraction protocol.

Keywords: convention on international trade in endangered species, cubic volume formula, forest transition savannah zones, pterocarpus erinaceus, smallian’s volume formula, tree information form

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1628 2D titanium, vanadium carbide MXene, and Polyaniline heterostructures for electrochemical energy storage

Authors: Ayomide A Sijuade, Nafiza Anjum

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The rising demand to meet the need for clean and sustainable energy solutions has led the market to create effective energy storage technologies. In this study, we look at the possibility of using a heterostructure made of polyaniline (PANI), titanium carbide (Ti₃C₂), and vanadium carbide (V₂C) for energy storage devices. V₂C is a two-dimensional transition metal carbide with remarkable mechanical and electrical conductivity. Ti₃C2 has solid thermal conductivity and mechanical strength. PANI, on the other hand, is a conducting polymer with customizable electrical characteristics and environmental stability. Layer-by-layer assembly creates the heterostructure of V₂C, Ti₃C₂, and PANI, allowing for precise film thickness and interface quality control. Structural and morphological characterization is carried out using X-ray diffraction, scanning electron microscopy, and atomic force microscopy. For energy storage applications, the heterostructure’s electrochemical performance is assessed. Electrochemical experiments, such as cyclic voltammetry and galvanostatic charge-discharge tests, examine the heterostructure’s charge storage capacity, cycle stability, and rate performance. Comparing the heterostructure to the individual components reveals better energy storage capabilities. V₂C, Ti₃C₂, and PANI synergize to increase specific capacitance, boost charge storage, and prolong cycling stability. The heterostructure’s unique arrangement of 2D materials and conducting polymers promotes effective ion diffusion and charge transfer processes, improving the effectiveness of energy storage. The heterostructure also exhibits remarkable electrochemical stability, which minimizes capacity loss after repeated cycling. The longevity and long-term dependability of energy storage systems depend on this quality. By examining the potential of V₂C, Ti₃C₂, and PANI heterostructures, the results of this study expand energy storage technology. These materials’ specialized integration and design show potential for use in hybrid energy storage systems, lithium-ion batteries, and supercapacitors. Overall, the development of high-performance energy storage devices utilizing V₂C, Ti₃C₂, and PANI heterostructures is clarified by this research, opening the door to the realization of effective, long-lasting, and eco-friendly energy storage solutions to satisfy the demands of the modern world.

Keywords: MXenes, energy storage materials, conductive polymers, composites

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1627 Public-Private Partnership Projects in Canada: A Case Study Approach

Authors: Samuel Carpintero

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Public-private partnerships (PPP) arrangements have emerged all around the world as a response to infrastructure deficits and the need to refurbish existing infrastructure. The motivations of governments for embarking on PPPs for the delivery of public infrastructure are manifold, and include on-time and on-budget delivery as well as access to private project management expertise. The PPP formula has been used by some State governments in United States and Canada, where the participation of private companies in financing and managing infrastructure projects has increased significantly in the last decade, particularly in the transport sector. On the one hand, this paper examines the various ways used in these two countries in the implementation of PPP arrangements, with a particular focus on risk transfer. The examination of risk transfer in this paper is carried out with reference to the following key PPP risk categories: construction risk, revenue risk, operating risk and availability risk. The main difference between both countries is that in Canada the demand risk remains usually within the public sector whereas in the United States this risk is usually transferred to the private concessionaire. The aim is to explore which lessons can be learnt from both models than might be useful for other countries. On the other hand, the paper also analyzes why the Spanish companies have been so successful in winning PPP contracts in North America during the past decade. Contrary to the Latin American PPP market, the Spanish companies do not have any cultural advantage in the case of the United States and Canada. Arguably, some relevant reasons for the success of the Spanish groups are their extensive experience in PPP projects (that dates back to the late 1960s in some cases), their high technical level (that allows them to be aggressive in their bids), and their good position and track-record in the financial markets. The article’s empirical base consists of data provided by official sources of both countries as well as information collected through face-to-face interviews with public and private representatives of the stakeholders participating in some of the PPP schemes. Interviewees include private project managers of the concessionaires, representatives of banks involved as financiers in the projects, and experts in the PPP industry with close knowledge of the North American market. Unstructured in-depth interviews have been adopted as a means of investigation for this study because of its powers to achieve honest and robust responses and to ensure realism in the collection of an overall impression of stakeholders’ perspectives.

Keywords: PPP, concession, infrastructure, construction

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1626 Design, Synthesis and Evaluation of 4-(Phenylsulfonamido)Benzamide Derivatives as Selective Butyrylcholinesterase Inhibitors

Authors: Sushil Kumar Singh, Ashok Kumar, Ankit Ganeshpurkar, Ravi Singh, Devendra Kumar

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In spectrum of neurodegenerative diseases, Alzheimer’s disease (AD) is characterized by the presence of amyloid β plaques and neurofibrillary tangles in the brain. It results in cognitive and memory impairment due to loss of cholinergic neurons, which is considered to be one of the contributing factors. Donepezil, an acetylcholinesterase (AChE) inhibitor which also inhibits butyrylcholinesterase (BuChE) and improves the memory and brain’s cognitive functions, is the most successful and prescribed drug to treat the symptoms of AD. The present work is based on designing of the selective BuChE inhibitors using computational techniques. In this work, machine learning models were trained using classification algorithms followed by screening of diverse chemical library of compounds. The various molecular modelling and simulation techniques were used to obtain the virtual hits. The amide derivatives of 4-(phenylsulfonamido) benzoic acid were synthesized and characterized using 1H & 13C NMR, FTIR and mass spectrometry. The enzyme inhibition assays were performed on equine plasma BuChE and electric eel’s AChE by method developed by Ellman et al. Compounds 31, 34, 37, 42, 49, 52 and 54 were found to be active against equine BuChE. N-(2-chlorophenyl)-4-(phenylsulfonamido)benzamide and N-(2-bromophenyl)-4-(phenylsulfonamido)benzamide (compounds 34 and 37) displayed IC50 of 61.32 ± 7.21 and 42.64 ± 2.17 nM against equine plasma BuChE. Ortho-substituted derivatives were more active against BuChE. Further, the ortho-halogen and ortho-alkyl substituted derivatives were found to be most active among all with minimal AChE inhibition. The compounds were selective toward BuChE.

Keywords: Alzheimer disease, butyrylcholinesterase, machine learning, sulfonamides

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1625 Polymer Nanostructures Based Catalytic Materials for Energy and Environmental Applications

Authors: S. Ghosh, L. Ramos, A. N. Kouamé, A.-L. Teillout, H. Remita

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Catalytic materials have attracted continuous attention due to their promising applications in a variety of energy and environmental applications including clean energy, energy conversion and storage, purification and separation, degradation of pollutants and electrochemical reactions etc. With the advanced synthetic technologies, polymer nanostructures and nanocomposites can be directly synthesized through soft template mediated approach using swollen hexagonal mesophases and modulate the size, morphology, and structure of polymer nanostructures. As an alternative to conventional catalytic materials, one-dimensional PDPB polymer nanostructures shows high photocatalytic activity under visible light for the degradation of pollutants. These photocatalysts are very stable with cycling. Transmission electron microscopy (TEM), and AFM-IR characterizations reveal that the morphology and structure of the polymer nanostructures do not change after photocatalysis. These stable and cheap polymer nanofibers and metal polymer nanocomposites are easy to process and can be reused without appreciable loss of activity. The polymer nanocomposites formed via one pot chemical redox reaction with 3.4 nm Pd nanoparticles on poly(diphenylbutadiyne) (PDPB) nanofibers (30 nm). The reduction of Pd (II) ions is accompanied by oxidative polymerization leading to composites materials. Hybrid Pd/PDPB nanocomposites used as electrode materials for the electrocatalytic oxidation of ethanol without using support of proton exchange Nafion membrane. Hence, these conducting polymer nanofibers and nanocomposites offer the perspective of developing a new generation of efficient photocatalysts for environmental protection and in electrocatalysis for fuel cell applications.

Keywords: conducting polymer, swollen hexagonal mesophases, solar photocatalysis, electrocatalysis, water depollution

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1624 Chromatographic Fingerprint Analysis of Methanolic Extract of Camellia sinensis Linn. Leaves

Authors: Babar Ali, Mohammad Rashid, Showkat Rasool Mir, Mohammad Ali, Saiba Shams

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Background: The plant Camellia sinensis (Theaceae) is an evergreen shrub indigenous to Assam (India) and parts of China and Japan. Traditional Chinese medicine has recommended green tea for headaches, body aches and pains, digestion, enhancement of immune defense, detoxification, as an energizer and to prolong life. The leaves have more than 700 chemical constituents, among which flavanoids, amino acids, vitamins (C, E, K), caffeine and polysaccharides. Adulteration and substitution may affect the quality of formulation containing tea leaves. Standardization of medicinal preparation is essential for further therapeutic results and for global acceptance. Hence, chromatographic fingerprint profiles were carried out for establishing the standards. Materials and methods: TLC studies for methanolic extracts of the leaves of Camellia sinensis were carried out in a new developed solvent system, Toluene: Ethyl acetate: Formic acid (7:3:1). TLC plates were dried in air, visualized in UV at wavelengths 254 nm and 366 nm and photographed. Results: Results provide valuable clue regarding their polarity and selection of solvents for separation of phytochemicals. Fingerprinting of methanolic extract of Camellia sinensis leaves revealed the presence of various phytochemicals in UV at 254 nm and 366 nm. Conclusion: Fingerprint profile is quite helpful in setting up of standards and thus to keep a check on intentional/unintentional adulteration. TLC offers major advantages over other conventional chromatographic techniques such as unsurpassed flexibility (esp. stationary and mobile phase), choice of detection wavelength, user friendly, rapid and cost effective.

Keywords: Cammelia sinensis Linn., standardization, methanolic extract, thin layer chromatography

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1623 A U-Net Based Architecture for Fast and Accurate Diagram Extraction

Authors: Revoti Prasad Bora, Saurabh Yadav, Nikita Katyal

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In the context of educational data mining, the use case of extracting information from images containing both text and diagrams is of high importance. Hence, document analysis requires the extraction of diagrams from such images and processes the text and diagrams separately. To the author’s best knowledge, none among plenty of approaches for extracting tables, figures, etc., suffice the need for real-time processing with high accuracy as needed in multiple applications. In the education domain, diagrams can be of varied characteristics viz. line-based i.e. geometric diagrams, chemical bonds, mathematical formulas, etc. There are two broad categories of approaches that try to solve similar problems viz. traditional computer vision based approaches and deep learning approaches. The traditional computer vision based approaches mainly leverage connected components and distance transform based processing and hence perform well in very limited scenarios. The existing deep learning approaches either leverage YOLO or faster-RCNN architectures. These approaches suffer from a performance-accuracy tradeoff. This paper proposes a U-Net based architecture that formulates the diagram extraction as a segmentation problem. The proposed method provides similar accuracy with a much faster extraction time as compared to the mentioned state-of-the-art approaches. Further, the segmentation mask in this approach allows the extraction of diagrams of irregular shapes.

Keywords: computer vision, deep-learning, educational data mining, faster-RCNN, figure extraction, image segmentation, real-time document analysis, text extraction, U-Net, YOLO

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1622 Contribution of Different Farming Systems to Soil and Ecological Health in Trans Nzoia County, Kenya

Authors: Janeth Chepkemoi, Richard Onwonga, Noel Templer, Elkana Kipkoech, Angela Gitau

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Conventional agriculture is one of the leading causes of land degradation, threatening the sustainability of food production. Organic farming promotes practices that have the potential of feeding the world while also promoting ecological health. A study was therefore carried out with the aim of conceptualizing how such farming systems are contributing to ecological health in Trans Nzoia County. 71 farmers were interviewed and data was collected on parameters such as land preparation, agroforestry, soil fertility management, soil and water conservation, and pests and diseases. A soil sample was also collected from each farm for laboratory analysis. Data collected were analyzed using Microsoft Excel and SPSS version 21. Results showed that 66% of the respondents practiced organic farming whereas 34% practiced conventional farming. Intercropping and crop rotations were the most common cropping systems and the most preferred land preparation tools among both organic and conventional farmers were tractors and hand hoes. Organic farms fared better in agroforestry, organic soil amendments, land and water conservation, and soil chemical properties. Pests and disease, however, affected organic farms more than conventional. The average nitrogen (%), K (Cmol/ kg and P (ppm) of organic soils were 0.26, 0.7 and 26.18 respectively, conventional soils were 0.21, 0.66 and 22.85. Soil organic carbon content of organic farms averaged a higher percentage of 2.07% as compared to 1.91 for the conventional. In conclusion, most farmers in Trans Nzoia County had transitioned into ecologically friendly farming practices that improved the quality and health of the soil and therefore promoted its sustainability.

Keywords: organic farming, conventional farming, ecological health, soil health

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1621 Artificial Intelligence in Bioscience: The Next Frontier

Authors: Parthiban Srinivasan

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With recent advances in computational power and access to enough data in biosciences, artificial intelligence methods are increasingly being used in drug discovery research. These methods are essentially a series of advanced statistics based exercises that review the past to indicate the likely future. Our goal is to develop a model that accurately predicts biological activity and toxicity parameters for novel compounds. We have compiled a robust library of over 150,000 chemical compounds with different pharmacological properties from literature and public domain databases. The compounds are stored in simplified molecular-input line-entry system (SMILES), a commonly used text encoding for organic molecules. We utilize an automated process to generate an array of numerical descriptors (features) for each molecule. Redundant and irrelevant descriptors are eliminated iteratively. Our prediction engine is based on a portfolio of machine learning algorithms. We found Random Forest algorithm to be a better choice for this analysis. We captured non-linear relationship in the data and formed a prediction model with reasonable accuracy by averaging across a large number of randomized decision trees. Our next step is to apply deep neural network (DNN) algorithm to predict the biological activity and toxicity properties. We expect the DNN algorithm to give better results and improve the accuracy of the prediction. This presentation will review all these prominent machine learning and deep learning methods, our implementation protocols and discuss these techniques for their usefulness in biomedical and health informatics.

Keywords: deep learning, drug discovery, health informatics, machine learning, toxicity prediction

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1620 Cost Benefit Analysis of Adoption of Climate Change Adaptation Options among Rural Rice Farmers in Nepal

Authors: Niranjan Devkota , Ram Kumar Phuya, Durga Lal Shreshta

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This paper estimates cost and benefit of adoption of climate change adaptation options available to the rural rice farmers of Nepal. Adoption of adaptation strategies, intensity of use of adaptation options, identification of labor and non-labor cost and finally per unit cost and benefit analysis of climate change adaptation were made. Multi-stage sampling technique was used to source respondents for the study and used structured questionnaire techniques to collect data from 773 households from seven districts; 3 from Terai and 4 from Hilly region of Nepal. The result revealed that there are 13 major adaptation options rice farmers practice in order to protect themselves from climatic risk. Among the given adaptation options, the first three popular adaptation options practiced by rice farmers are (i) increasing use of chemical fertilizer (60.93%) (ii) use of climate smart verities (49.29%) and (iii) change in nursery date (32.08%). Adaptation cost is obvious, based on that, the first three costly adaptation options are the alternative irrigation practice which incurred average cost of US $69.95 (US$ 1 = 102.84 Nepalese Rupees) followed by a denser plantation of local seeds ($ 20.69) and using climate smart varieties ($ 18.06). 88% farmers practiced more than one adaptation strategies on the same farm with the aim of reducing the effect of extreme climatic conditions. Total cost and revenue revealed that per unit total cost ranges from $28.34 to $32.79 whereas per unit total revenue ranges $33.4 to $49.02. Surprisingly, it is observed that farmers who do not adopt any adaptation options are able to receive highest income from per unit production. As Net Present Value (NPV) is positive and Benefit Cost Ration (BCR) is greater than one for every adaptation options that indicates the available adaptation options are profitable to the rice farmers.

Keywords: climate change, adaptation options, cost benefit analysis, rural rice farmers, Nepal

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1619 Small Community’s Proactive Thinking to Move from Zero to 100 Percent Water Reuse

Authors: Raj Chavan

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The City of Jal serves a population of approximately 3,500 people, including 2,100 permanent inhabitants and 1,400 oil and gas sector workers and RV park occupants. Over the past three years, Jal's population has increased by about 70 percent, mostly due to the oil and gas industry. The City anticipates that the population will exceed 4,200 by 2020, necessitating the construction of a new wastewater treatment plant (WWTP) because the old plant (aerated lagoon system) cannot accommodate such rapid population expansion without major renovations or replacement. Adhering to discharge permit restrictions has been challenging due to aging infrastructure and equipment replacement needs, as well as increasing nutrient loading to the wastewater collecting system from the additional oil and gas residents' recreational vehicles. The WWTP has not been able to maintain permit discharge standards for total nitrogen of less than 20 mg N/L and other characteristics in recent years. Based on discussions with the state's environmental department, it is likely that the future permit renewal would impose stricter conditions. Given its location in the dry, western part of the country, the City must rely on its meager groundwater supplies and scant annual precipitation. The city's groundwater supplies will be depleted sooner than predicted due to rising demand from the growing population for drinking, leisure, and other industrial uses (fracking). The sole type of reuse the city was engaging in (recreational reuse for a golf course) had to be put on hold because of an effluent water compliance issue. As of right now, all treated effluent is evaporated. The city's long-term goal is to become a zero-waste community that sends all of its treated wastewater effluent either to the golf course, Jal Lake, or the oil and gas industry for reuse. Hydraulic fracturing uses a lot of water, but if the oil and gas industry can use recycled water, it can reduce its impact on freshwater supplies. The City's goal of 100% reuse has been delayed by the difficulties of meeting the constraints of the regular discharge permit due to the large rise in influent loads and the aging infrastructure. The City of Jal plans to build a new WWTP that can keep up with the city's rapid population increase due to the oil and gas industry. Several treatment methods were considered in light of the City's needs and its long-term goals, but MBR was ultimately chosen recommended since it meets all of the permit's requirements while also providing 100 percent beneficial reuse. This talk will lay out the plan for the city to reach its goal of 100 percent reuse, as well as the various avenues for funding the small community that have been considered.

Keywords: membrane bioreactor, nitrogent, reuse, small community

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1618 Private Technology Parks–The New Engine for Innovation Development in Russia

Authors: K. Volkonitskaya, S. Lyapina

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According to the National Monitoring Centre of innovation infrastructure, scientific and technical activities and regional innovation systems by December 2014. 166 technology parks were established in Russia. Comparative analysis of technological parks performance in Russia, the USA, Israel and the European Union countries revealed significant reduction of key performance indicators in Russian innovation infrastructure institutes. The largest deviations were determined in the following indicators: new products and services launched, number of companies and jobs, amount of venture capital invested. Lower performance indicators of Russian technology parks can be partly explained by slack demand for national high-tech products and services, lack of qualified specialists in the sphere of innovation management and insufficient cooperation between different innovation infrastructure institutes. In spite of all constraints in innovation segment of Russian economy in 2010-2012 private investors for the first time proceeded to finance building of technological parks. The general purpose of the research is to answer two questions: why despite the significant investment risks private investors continue to implement such comprehensive infrastructure projects in Russia and is business model of private technological park more efficient than strategies of state innovation infrastructure institutes? The goal of the research was achieved by analyzing business models of private technological parks in Moscow, Kaliningrad, Astrakhan and Kazan. The research was conducted in two stages: the on-line survey of key performance indicators of private and state Russian technological parks and in-depth interviews with top managers and investors, who have already build private technological parks in by 2014 or are going to complete investment stage in 2014-2016. The results anticipated are intended to identify the reasons of efficient and inefficient technological parks performance. Furthermore, recommendations for improving the efficiency of state technological and industrial parks were formulated. Particularly, the recommendations affect the following issues: networking with other infrastructural institutes, services and infrastructure provided, mechanisms of public-private partnership and investment attraction. In general intensive study of private technological parks performance and development of effective mechanisms of state support can have a positive impact on the growth rates of the number of Russian technological, industrial and science parks.

Keywords: innovation development, innovation infrastructure, private technology park, public-private partnership

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1617 Mineralogy and Thermobarometry of Xenoliths in Basalt from the Chanthaburi-Trat Gem Fields, Thailand

Authors: Apichet Boonsoong

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In the Chanthaburi-Trat basalts, xenoliths are composed of essentially ultramafic xenoliths (particularly spinel lherzolite) with a few of an aggregate of feldspar. Some 19 ultramafic xenoliths were collected from 13 different locations. They range in size from 3.5 to 60mm across. Most are weathered and oxidized on the surface but fresh samples are obtained from cut surfaces. Chemical analyses were performed on carbon-coated polished thin sections using a fully automated CAMECA SX-50 electron microprobe (EMPA) in wavelength-dispersive mode. In thin section, they are seen to consist of variable amounts of olivine, clinopyroxene, orthopyroxene with minor spinel and plagioclase, and are classed as lherzolite. Modal compositions of the ultramafic nodules vary with olivine (60-75%), clinopyroxene (20-30%), orthopyroxene (0-15%), minor spinel (1-3%) and plagioclase (<1%). The essential minerals form an equigranular, medium- to coarse-grained, granoblastic texture, and all are in mutual contact indicating attainment of equilibrium. Reaction rims are common along the nodule margins and in some are also present along grain boundaries. Zoning occurs in clinopyroxene, and to a lesser extent in orthopyroxene. The homogeneity of mineral compositions in lherzolite xenoliths suggests the attainment of equilibrium. The equilibration temperatures of these xenoliths are estimated to be in the range of 973 to 1063°C. Pressure estimates are not so easily obtained because no suitable barometer exists for garnet-free lherzolites and so an indirect method was used. The general mineral assemblage of the lherzolite xenoliths and the absence of garnet indicate a pressure range of approximately 12–19kbar, which is equivalent to depths approximately of 38 to 60km.

Keywords: chanthaburi-trat basalts, spinel lherzolite, xenoliths, 973 to 1063°C, 38 to 60km

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1616 Algorithm for Modelling Land Surface Temperature and Land Cover Classification and Their Interaction

Authors: Jigg Pelayo, Ricardo Villar, Einstine Opiso

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The rampant and unintended spread of urban areas resulted in increasing artificial component features in the land cover types of the countryside and bringing forth the urban heat island (UHI). This paved the way to wide range of negative influences on the human health and environment which commonly relates to air pollution, drought, higher energy demand, and water shortage. Land cover type also plays a relevant role in the process of understanding the interaction between ground surfaces with the local temperature. At the moment, the depiction of the land surface temperature (LST) at city/municipality scale particularly in certain areas of Misamis Oriental, Philippines is inadequate as support to efficient mitigations and adaptations of the surface urban heat island (SUHI). Thus, this study purposely attempts to provide application on the Landsat 8 satellite data and low density Light Detection and Ranging (LiDAR) products in mapping out quality automated LST model and crop-level land cover classification in a local scale, through theoretical and algorithm based approach utilizing the principle of data analysis subjected to multi-dimensional image object model. The paper also aims to explore the relationship between the derived LST and land cover classification. The results of the presented model showed the ability of comprehensive data analysis and GIS functionalities with the integration of object-based image analysis (OBIA) approach on automating complex maps production processes with considerable efficiency and high accuracy. The findings may potentially lead to expanded investigation of temporal dynamics of land surface UHI. It is worthwhile to note that the environmental significance of these interactions through combined application of remote sensing, geographic information tools, mathematical morphology and data analysis can provide microclimate perception, awareness and improved decision-making for land use planning and characterization at local and neighborhood scale. As a result, it can aid in facilitating problem identification, support mitigations and adaptations more efficiently.

Keywords: LiDAR, OBIA, remote sensing, local scale

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1615 Preparation and Characterization of Transparent and Conductive SnO2 Thin Films by Spray Pyrolysis

Authors: V. Jelev, P. Petkov, P. Shindov

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Thin films of undoped and As-doped tin oxide (As:SnO2) were obtained on silicon and glass substrates at 450°- 480°C by spray pyrolysis technique. Tin chloride (SnCl4.5H2O) and As oxide (3As2O5.5H2O) were used as a source for Sn and As respectively. The As2O5 concentration was varied from 0 to 10 mol% in the starting water-alcoholic solution. The characterization of the films was provided with XRD, CEM, AFM and UV-VIS spectroscopy. The influence of the synthesis parameters (the temperature of the substrate, solution concentration, gas and solution flow rates, deposition time, nozzle-to substrate distance) on the optical, electrical and structural properties of the films was investigated. The substrate temperature influences on the surface topography, structure and resistivity of the films. Films grown at low temperatures (<300°C) are amorphous whereas this deposited at higher temperatures have certain degree of polycrystallinity. Thin oxide films deposited at 450°C are generally polycrystalline with tetragonal rutile structure. The resistivity decreases with dopant concentration. The minimum resistivity was achieved at dopant concentration about 2.5 mol% As2O5 in the solution. The transmittance greater than 80% and resistivity smaller than 7.5.10-4Ω.cm were achieved in the films deposited at 480°C. The As doped films (SnO2: As) deposited on silicon substrates was used for preparation of a large area position sensitive photodetector (PSD), acting on the base of a lateral photovoltaic effect. The position characteristic of PSD is symmetric to the zero and linear in the 80% of the active area. The SnO2 films are extremely stable under typical environmental conditions and extremely resistant to chemical etching.

Keywords: metal oxide film, SnO2 film, position sensitive photodetectors (PSD), lateral photovoltaic effect

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1614 Subsea Processing: Deepwater Operation and Production

Authors: Md Imtiaz, Sanchita Dei, Shubham Damke

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In recent years, there has been a rapidly accelerating shift from traditional surface processing operations to subsea processing operation. This shift has been driven by a number of factors including the depletion of shallow fields around the world, technological advances in subsea processing equipment, the need for production from marginal fields, and lower initial upfront investment costs compared to traditional production facilities. Moving production facilities to the seafloor offers a number of advantage, including a reduction in field development costs, increased production rates from subsea wells, reduction in the need for chemical injection, minimization of risks to worker ,reduction in spills due to hurricane damage, and increased in oil production by enabling production from marginal fields. Subsea processing consists of a range of technologies for separation, pumping, compression that enables production from offshore well without the need for surface facilities. At present, there are two primary technologies being used for subsea processing: subsea multiphase pumping and subsea separation. Multiphase pumping is the most basic subsea processing technology. Multiphase pumping involves the use of boosting system to transport the multiphase mixture through pipelines to floating production vessels. The separation system is combined with single phase pumps or water would be removed and either pumped to the surface, re-injected, or discharged to the sea. Subsea processing can allow for an entire topside facility to be decommissioned and the processed fluids to be tied back to a new, more distant, host. This type of application reduces costs and increased both overall facility and integrity and recoverable reserve. In future, full subsea processing could be possible, thereby eliminating the need for surface facilities.

Keywords: FPSO, marginal field, Subsea processing, SWAG

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1613 Antibacterial Activity of Flavonoids from Corn Silk (Zea mays L.) in Propionibacterium acne, Staphylococcus Aureus and Staphylococcus Epidermidis

Authors: Fitri Ayu, Nadia, Tanti, Putri, Fatkhan, Pasid Harlisa, Suparmi

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Acne is a skin abnormal conditions experienced by many teens, this is caused by various factors such as the climate is hot, humid and excessive sun exposure can aggravate acne because it will lead to excess oil production. Flavonoids form complex compounds against extracellular proteins that disrupt the integrity of bacterial cell membrane in a way denature bacterial cell proteins and bacterial cell membrane damage. This study aimed to test the antibacterial activity of corn silk extract with a concentration of 10 %, 20 %, 30 %, 40 %, 50 %, 60 %, 70 %, 80 %, 90 % and 100 % in vitro by measuring the inhibition of the growth of bacteria Propionibacterium acne, Staphylococcus aureus and Staphylococcus epidermis then compared with the standard antibiotic clindamycin. Extracts tested by Disk Diffusion Method, in which the blank disc soaked with their respective corn silk extract concentration for 15-30 minutes and then the medium of bacteria that have been planted with Propionibacterium acne, Staphylococcus aureus and Staphylococcus epidermis in the given disk that already contains extracts with various concentration. Incubated for 24 hours and then measured the growth inhibition zone Propionibacterium acne, Staphylococcus aureus and Staphylococcus epidermidis. Corn silk contains flavonoids, is shown by the test of flavonoids in corn silk extract by using a tube heating and without heating. Flavonoid in corn silk potentially as anti acne by inhibiting the growth of bacteria that cause acne. Corn silk extract concentration which has the highest antibacterial activity is then performed in a cream formulation and evaluation test of physical and chemical properties of the resulting cream preparation.

Keywords: antibacterial, flavonoid, corn silk, acne

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1612 How to Reach Net Zero Emissions? On the Permissibility of Negative Emission Technologies and the Danger of Moral Hazards

Authors: Hanna Schübel, Ivo Wallimann-Helmer

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In order to reach the goal of the Paris Agreement to not overshoot 1.5°C of warming above pre-industrial levels, various countries including the UK and Switzerland have committed themselves to net zero emissions by 2050. The employment of negative emission technologies (NETs) is very likely going to be necessary for meeting these national objectives as well as other internationally agreed climate targets. NETs are methods of removing carbon from the atmosphere and are thus a means for addressing climate change. They range from afforestation to technological measures such as direct air capture and carbon storage (DACCS), where CO2 is captured from the air and stored underground. As all so-called geoengineering technologies, the development and deployment of NETs are often subject to moral hazard arguments. As these technologies could be perceived as an alternative to mitigation efforts, so the argument goes, they are potentially a dangerous distraction from the main target of mitigating emissions. We think that this is a dangerous argument to make as it may hinder the development of NETs which are an essential element of net zero emission targets. In this paper we argue that the moral hazard argument is only problematic if we do not reflect upon which levels of emissions are at stake in order to meet net zero emissions. In response to the moral hazard argument we develop an account of which levels of emissions in given societies should be mitigated and not be the target of NETs and which levels of emissions can legitimately be a target of NETs. For this purpose, we define four different levels of emissions: the current level of individual emissions, the level individuals emit in order to appear in public without shame, the level of a fair share of individual emissions in the global budget, and finally the baseline of net zero emissions. At each level of emissions there are different subjects to be assigned responsibilities if societies and/or individuals are committed to the target of net zero emissions. We argue that all emissions within one’s fair share do not demand individual mitigation efforts. The same holds with regard to individuals and the baseline level of emissions necessary to appear in public in their societies without shame. Individuals are only under duty to reduce their emissions if they exceed this baseline level. This is different for whole societies. Societies demanding more emissions to appear in public without shame than the individual fair share are under duty to foster emission reductions and are not legitimate to reduce by introducing NETs. NETs are legitimate for reducing emissions only below the level of fair shares and for reaching net zero emissions. Since access to NETs to achieve net zero emissions demands technology not affordable to individuals there are also no full individual responsibilities to achieve net zero emissions. This is mainly a responsibility of societies as a whole.

Keywords: climate change, mitigation, moral hazard, negative emission technologies, responsibility

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1611 Analyzing Growth Trends of the Built Area in the Precincts of Various Types of Tourist Attractions in India: 2D and 3D Analysis

Authors: Yarra Sulina, Nunna Tagore Sai Priya, Ankhi Banerjee

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With the rapid growth in tourist arrivals, there has been a huge demand for the growth of infrastructure in the destinations. With the increasing preference of tourists to stay near attractions, there has been a considerable change in the land use around tourist sites. However, with the inclusion of certain regulations and guidelines provided by the authorities based on the nature of tourism activity and geographical constraints, the pattern of growth of built form is different for various tourist sites. Therefore, this study explores the patterns of growth of built-up for a decade from 2009 to 2019 through two-dimensional and three-dimensional analysis. Land use maps are created through supervised classification of satellite images obtained from LANDSAT 4-5 and LANDSAT 8 for 2009 and 2019, respectively. The overall expansion of the built-up area in the region is analyzed in relation to the distance from the city's geographical center and the tourism-related growth regions are identified which are influenced by the proximity of tourist attractions. The primary tourist sites of various destinations with different geographical characteristics and tourism activities, that have undergone a significant increase in built-up area and are occupied with tourism-related infrastructure are selected for further study. Proximity analysis of the tourism-related growth sites is carried out to delineate the influence zone of the tourist site in a destination. Further, a temporal analysis of volumetric growth of built form is carried out to understand the morphology of the tourist precincts over time. The Digital Surface Model (DSM) and Digital Terrain Model (DTM) are used to extract the building footprints along with building height. Factors such as building height, and building density are evaluated to understand the patterns of three-dimensional growth of the built area in the region. The study also explores the underlying reasons for such changes in built form around various tourist sites and predicts the impact of such growth patterns in the region. The building height and building density around tourist site creates a huge impact on the appeal of the destination. The surroundings that are incompatible with the theme of the tourist site have a negative impact on the attractiveness of the destination that leads to negative feedback by the tourists, which is not a sustainable form of development. Therefore, proper spatial measures are necessary in terms of area and volume of the built environment for a healthy and sustainable environment around the tourist sites in the destination.

Keywords: sustainable tourism, growth patterns, land-use changes, 3-dimensional analysis of built-up area

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1610 A Study on the Effect of the Work-Family Conflict on Work Engagement: A Mediated Moderation Model of Emotional Exhaustion and Positive Psychology Capital

Authors: Sungeun Hyun, Sooin Lee, Gyewan Moon

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Work-Family Conflict has been an active research area for the past decades. Work-Family Conflict harms individuals and organizations, it is ultimately expected to bring the cost of losses to the company in the long run. WFC has mainly focused on effects of organizational effectiveness and job attitude such as Job Satisfaction, Organizational Commitment, and Turnover Intention variables. This study is different from consequence variable with previous research. For this purpose, we selected the positive job attitude 'Work Engagement' as a consequence of WFC. This research has its primary research purpose in identifying the negative effects of the Work-Family Conflict, and started out from the recognition of the problem that the research on the direct relationship on the influence of the WFC on Work Engagement is lacking. Based on the COR(Conservation of resource theory) and JD-R(Job Demand- Resource model), the empirical study model to examine the negative effects of WFC with Emotional Exhaustion as the link between WFC and Work Engagement was suggested and validated. Also, it was analyzed how much Positive Psychological Capital may buffer the negative effects arising from WFC within this relationship, and the Mediated Moderation model controlling the indirect effect influencing the Work Engagement by the Positive Psychological Capital mediated by the WFC and Emotional Exhaustion was verified. Data was collected by using questionnaires distributed to 500 employees engaged manufacturing, services, finance, IT industry, education services, and other sectors, of which 389 were used in the statistical analysis. The data are analyzed by statistical package, SPSS 21.0, SPSS macro and AMOS 21.0. The hierarchical regression analysis, SPSS PROCESS macro and Bootstrapping method for hypothesis testing were conducted. Results showed that all hypotheses are supported. First, WFC showed a negative effect on Work Engagement. Specifically, WIF appeared to be on more negative effects than FIW. Second, Emotional exhaustion found to mediate the relationship between WFC and Work Engagement. Third, Positive Psychological Capital showed to moderate the relationship between WFC and Emotional Exhaustion. Fourth, the effect of mediated moderation through the integration verification, Positive Psychological Capital demonstrated to buffer the relationship among WFC, Emotional Exhastion, and Work Engagement. Also, WIF showed a more negative effects than FIW through verification of all hypotheses. Finally, we discussed the theoretical and practical implications on research and management of the WFC, and proposed limitations and future research directions of research.

Keywords: emotional exhaustion, positive psychological capital, work engagement, work-family conflict

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1609 Integrated Two Stage Processing of Biomass Conversion to Hydroxymethylfurfural Esters Using Ionic Liquid as Green Solvent and Catalyst: Synthesis of Mono Esters

Authors: Komal Kumar, Sreedevi Upadhyayula

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In this study, a two-stage process was established for the synthesis of HMF esters using ionic liquid acid catalyst. Ionic liquid catalyst with different strength of the Bronsted acidity was prepared in the laboratory and characterized using 1H NMR, FT-IR, and 13C NMR spectroscopy. Solid acid catalyst from the ionic liquid catalyst was prepared using the immobilization method. The acidity of the synthesized acid catalyst was measured using Hammett function and titration method. Catalytic performance was evaluated for the biomass conversion to 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA) in methyl isobutyl ketone (MIBK)-water biphasic system. A good yield of 5-HMF and LA was found at the different composition of MIBK: Water. In the case of MIBK: Water ratio 10:1, good yield of 5-HMF was observed at ambient temperature 150˚C. Upgrading of 5-HMF into monoesters from the reaction of 5-HMF and reactants using biomass-derived monoacid were performed. Ionic liquid catalyst with -SO₃H functional group was found to be best efficient in comparative of a solid acid catalyst for the esterification reaction and biomass conversion. A good yield of 5-HMF esters with high 5-HMF conversion was found to be at 105˚C using the best active catalyst. In this process, process A was the hydrothermal conversion of cellulose and monomer into 5-HMF and LA using acid catalyst. And the process B was the esterification followed by using similar acid catalyst. All monoesters of 5-HMF synthesized here can be used in chemical, cross linker for adhesive or coatings and pharmaceutical industry. A theoretical density functional theory (DFT) study for the optimization of the ionic liquid structure was performed using the Gaussian 09 program to find out the minimum energy configuration of ionic liquid catalyst.

Keywords: biomass conversion, 5-HMF, Ionic liquid, HMF ester

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1608 Municipal Solid Waste Management Using Life Cycle Assessment Approach: Case Study of Maku City, Iran

Authors: L. Heidari, M. Jalili Ghazizade

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This paper aims to determine the best environmental and economic scenario for Municipal Solid Waste (MSW) management of the Maku city by using Life Cycle Assessment (LCA) approach. The functional elements of this study are collection, transportation, and disposal of MSW in Maku city. Waste composition and density, as two key parameters of MSW, have been determined by field sampling, and then, the other important specifications of MSW like chemical formula, thermal energy and water content were calculated. These data beside other information related to collection and disposal facilities are used as a reliable source of data to assess the environmental impacts of different waste management options, including landfills, composting, recycling and energy recovery. The environmental impact of MSW management options has been investigated in 15 different scenarios by Integrated Waste Management (IWM) software. The photochemical smog, greenhouse gases, acid gases, toxic emissions, and energy consumption of each scenario are measured. Then, the environmental indices of each scenario are specified by weighting these parameters. Economic costs of scenarios have been also compared with each other based on literature. As final result, since the organic materials make more than 80% of the waste, compost can be a suitable method. Although the major part of the remaining 20% of waste can be recycled, due to the high cost of necessary equipment, the landfill option has been suggested. Therefore, the scenario with 80% composting and 20% landfilling is selected as superior environmental and economic scenario. This study shows that, to select a scenario with practical applications, simultaneously environmental and economic aspects of different scenarios must be considered.

Keywords: IWM software, life cycle assessment, Maku, municipal solid waste management

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1607 Wettability Properties of Pineapple Leaf Fibers and Banana Pseudostem Fibers Treated by Cold Plasma

Authors: Tatiana Franco, Hugo A. Estupinan

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Banana pseudostem fiber (BPF) and pineapple leaf fiber (PLF) for their excellent mechanical properties and biodegradability characteristics arouse interest in different areas of research. F In tropical regions, where the banana pseudostem and the pineapple leaf are transformed into hard-to-handle solid waste, they can be low-cost raw material and environmentally sustainable in research for composite materials. In terms of functionality of this type of fiber, an open structure would allow the adsorption and retention of organic, inorganic and metallic species. In general, natural fibers have closed structures on their surface with intricate internal arrangements that can be used for the solution of environmental problems and other technological uses, however it is not possible to access their internal structure and sublayers, exposing the fibers in the natural state. An alternative method to chemical and enzymatic treatment are the processes with the plasma treatments, which are known to be clean, economical and controlled. In this type of treatment, a gas contained in a reactor in the form of plasma acts on the fiber generating changes in its structure, morphology and topography. This work compares the effects on fibers of PLF and BPF treated with cold argon plasma, alternating time and current. These fibers are grown in the regions of Antioquia-Colombia. The morphological, compositional and wettability properties of the fibers were analyzed by Raman microscopy, contact angle measurements, scanning electron microscopy (SEM) and atomic force microscopy analysis (AFM). The treatment with cold plasma on PLF and BPF allowed increasing its wettability, the topography and the microstructural relationship between lignin and cellulose.

Keywords: cold plasma, contact angle, natural fibers, Raman, SEM, wettability

Procedia PDF Downloads 142
1606 Evaluating Textbooks for Brazilian Air Traffic Controllers’ English Language Training: A Checklist Proposal

Authors: Elida M. R. Bonifacio

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English language proficiency has become an essential issue in aviation communication after aviation incidents, and accidents happened. Lack of proficiency or inappropriate use of the English language has been found as one of the factors that cause most of those incidents or accidents. Therefore, the International Civil Aviation Organization (ICAO) established the requirements for minimum English language proficiency of aviation personnel, especially pilots and air traffic controllers in the 192 member states. In Brazil, the discussions about this topic became patent after an accident that occurred in 2006, which was a mid-air collision and costed the life of 154 passengers and crew members. Thus, the number of schools and private practitioners willing to teach English for aviation purposes started to increase. Although the number of teaching materials internationally used for general purposes is relatively large, it would be inappropriate to adopt the same materials in classes that focus on communication in aviation contexts. On the contrary, the options of aviation English materials are scarce; moreover, they are internationally used and may not fulfill the linguistic needs of all their users around the world. In order to diminish the problems that Brazilian practitioners may encounter in the adoption of materials that demand a great level of adaptation to meet their students’ needs, a checklist was thought to evaluate textbooks. The aim of this paper is to propose a checklist that evaluates textbooks used in English language training of Brazilian air traffic controllers. The criteria used to compound the checklist are based on materials development literature, as well as on linguistic requirements established by ICAO on its publications, on English for Specific Purposes (ESP) principles, and on Brazilian aviation English language proficiency test format. The checklist has as main indicators the language learning tenets under which the book was written, graphical features, lexical, grammatical and functional competencies required for minimum proficiency, similarities to official testing format, and support materials, totaling 117 items marked as YES, NO or PARTIALLY. In order to verify if the use of the checklist is effective, an aviation English textbook was evaluated. From this evaluation, it is possible to measure quantitatively how much the material meets the students’ needs and to offer a tool to help professionals engaged in aviation English teaching around the world to choose the most appropriate textbook according to their audience. From the results, practitioners are able to verify which items the material does not fulfill and to make proper adaptations since the perfect material will be difficult to find.

Keywords: aviation English, ICAO, materials development, English language proficiency

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1605 Component Test of Martensitic/Ferritic Steels and Nickel-Based Alloys and Their Welded Joints under Creep and Thermo-Mechanical Fatigue Loading

Authors: Daniel Osorio, Andreas Klenk, Stefan Weihe, Andreas Kopp, Frank Rödiger

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Future power plants currently face high design requirements due to worsening climate change and environmental restrictions, which demand high operational flexibility, superior thermal performance, minimal emissions, and higher cyclic capability. The aim of the paper is, therefore, to investigate the creep and thermo-mechanical material behavior of improved materials experimentally and welded joints at component scale under near-to-service operating conditions, which are promising for application in highly efficient and flexible future power plants. These materials promise an increase in flexibility and a reduction in manufacturing costs by providing enhanced creep strength and, therefore, the possibility for wall thickness reduction. At the temperature range between 550°C and 625°C, the investigation focuses on the in-phase thermo-mechanical fatigue behavior of dissimilar welded joints of conventional materials (ferritic and martensitic material T24 and T92) to nickel-based alloys (A617B and HR6W) by means of membrane test panels. The temperature and external load are varied in phase during the test, while the internal pressure remains constant. At the temperature range between 650°C and 750°C, it focuses on the creep behavior under multiaxial stress loading of similar and dissimilar welded joints of high temperature resistant nickel-based alloys (A740H, A617B, and HR6W) by means of a thick-walled-component test. In this case, the temperature, the external axial load, and the internal pressure remain constant during testing. Numerical simulations are used for the estimation of the axial component load in order to induce a meaningful damage evolution without causing a total component failure. Metallographic investigations after testing will provide support for understanding the damage mechanism and the influence of the thermo-mechanical load and multiaxiality on the microstructure change and on the creep and TMF- strength.

Keywords: creep, creep-fatigue, component behaviour, weld joints, high temperature material behaviour, nickel-alloys, high temperature resistant steels

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1604 Extent of Fruit and Vegetable Waste at Wholesaler Stage of the Food Supply Chain in Western Australia

Authors: P. Ghosh, S. B. Sharma

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The growing problem of food waste is causing unacceptable economic, environmental and social impacts across the globe. In Australia, food waste is estimated at about AU$8 billion per year; however, information on the extent of wastage at different stages of the food value chain from farm to fork is very limited. This study aims to identify causes for and extent of food waste at wholesaler stage of the food value chain in the state of Western Australia. It also explores approaches applied to reduce and utilize food waste by the wholesalers. The study was carried out at Perth city market in Caning Vale, the main wholesale distribution centre for fruits and vegetables in Western Australia. A survey questionnaire was prepared and shared with 51 wholesalers and their responses to 10 targeted questions on quantity of produce (fruits and vegetables) delivery received and further supplied, reasons for waste generation and innovations applied or being considered to reduce and utilize food waste. Data were computed using the Statistical Package for the Social Sciences (SPSS version 21). Among the wholesalers 52% were primary wholesalers (buy produce directly from growers) and 48% were secondary wholesalers (buy produce in bulk from major wholesalers and supply to the local retail market, caterers, and customers with specific requirements). Average fruit and vegetable waste was 180 Kilogram per week per primary wholesaler and 30 Kilogram per secondary wholesaler. Based on this survey, the fruit and vegetable waste at wholesaler stage was estimated at about 286 tonnes per year. The secondary wholesalers distributed pre-ordered commodities, which minimized the potential to cause waste. Non-parametric test (Mann Whitney test) was carried out to assess contributions of wholesalers to waste generation. Over 56% of secondary wholesalers generally had nothing to bin as waste. Pearson’s correlation coefficient analysis showed positive correlation (r = 0.425; P=0.01) between the quantity of produce received and waste generated. Low market demand was the predominant reason identified by the wholesalers for waste generation. About a third of the wholesalers suggested that high cosmetic standards for fruits and vegetables - appearance, shape, and size - should be relaxed to reduce waste. Donation of unutilized fruits and vegetables to charity was overwhelmingly (95%) considered as one of the best options for utilization of discarded produce. The extent of waste at other stages of fruit and vegetable supply chain is currently being studied.

Keywords: food waste, fruits and vegetables, supply chain, waste generation

Procedia PDF Downloads 297
1603 Numerical Simulation of Flow and Heat Transfer Characteristics with Various Working Conditions inside a Reactor of Wet Scrubber

Authors: Jonghyuk Yoon, Hyoungwoon Song, Youngbae Kim, Eunju Kim

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Recently, with the rapid growth of semiconductor industry, lots of interests have been focused on after treatment system that remove the polluted gas produced from semiconductor manufacturing process, and a wet scrubber is the one of the widely used system. When it comes to mechanism of removing the gas, the polluted gas is removed firstly by chemical reaction in a reactor part. After that, the polluted gas stream is brought into contact with the scrubbing liquid, by spraying it with the liquid. Effective design of the reactor part inside the wet scrubber is highly important since removal performance of the polluted gas in the reactor plays an important role in overall performance and stability. In the present study, a CFD (Computational Fluid Dynamics) analysis was performed to figure out the thermal and flow characteristics inside unit a reactor of wet scrubber. In order to verify the numerical result, temperature distribution of the numerical result at various monitoring points was compared to the experimental result. The average error rates (12~15%) between them was shown and the numerical result of temperature distribution was in good agreement with the experimental data. By using validated numerical method, the effect of the reactor geometry on heat transfer rate was also taken into consideration. Uniformity of temperature distribution was improved about 15%. Overall, the result of present study could be useful information to identify the fluid behavior and thermal performance for various scrubber systems. This project is supported by the ‘R&D Center for the reduction of Non-CO₂ Greenhouse gases (RE201706054)’ funded by the Korea Ministry of Environment (MOE) as the Global Top Environment R&D Program.

Keywords: semiconductor, polluted gas, CFD (Computational Fluid Dynamics), wet scrubber, reactor

Procedia PDF Downloads 127
1602 Challenging Airway Management for Tracheal Compression Due to a Rhabdomyosarcoma

Authors: Elena Parmentier, Henrik Endeman

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Introduction: Large mediastinal masses often present with diagnostic and clinical challenges due to compression of the respiratory and hemodynamic system. We present a case of a mediastinal mass with symptomatic mechanical compression of the trachea, resulting in challenging airway management. Methods: We present a case of 66-year-old male, complaining of progressive dysphagia. Initial esophagogastroscopy revealed a stenosis secondary to external compression, biopsies were inconclusive. Additional CT scan showed a large mediastinal mass of unknown origin, situated between the vertebrae and esophagus. Symptoms progressed and patient developed dyspnea and stridor. A new CT showed quick growth of the mass with compression of the trachea, subglottic to just above the carina. A tracheal covered stent was successfully placed. Endobronchial ultrasound revealed a large irregular mass without tracheal invasion, biopsies were taken. 4 days after stent placement, the patients’ condition deteriorated with worsening of stridor, dyspnea and desaturation. Migration of the tracheal stent into the right main bronchus was seen on chest X ray, with obstruction of the left main bronchus and secondary atelectasis. Different methods have been described in the literature for tracheobronchial stent removal (surgical, endoscopic, fluoroscopyguided), our first choice in this case was flexible bronchoscopy. However, this revealed tracheal compression above the migrated stent and passage of the scope occurred impossible. Patient was admitted to the ICU, high-flow nasal oxygen therapy was started and the situation stabilized, giving time for extensive assessment and preparation of the airway management approach. Close cooperation between the intensivist, pulmonologist, anesthesiologist and otorhinolaryngologist was essential. Results: In case of sudden deterioration, a protocol for emergency situations was made. Given the increased risk of additional tracheal compression after administration of neuromuscular blocking agents, an approach with awake fiberoptic intubation maintaining spontaneous ventilation was proposed. However, intubation without retrieval of the tracheal stent was found undesirable due to expected massive shunting over the left atelectatic lung. As rescue option, assistance of extracorporeal circulation was considered and perfusionist was kept on standby. The patient stayed stable and was transferred to the operating theatre. High frequency jet ventilation under general anesthesia resulted in desaturations up to 50%, making rigid bronchoscopy impossible. Subsequently an endotracheal tube size 8 could be placed successfully and the stent could be retrieved via bronchoscopy over (and with) the tube, after which the patient was reintubated. Finally, a tracheostomy (Shiley™ Tracheostomy Tube With Cuff, size 8) was placed, fiberoptic control showed a patent airway. Patient was readmitted to the ICU and could be quickly weaned of the ventilator. Pathology was positive for rhabdomyosarcoma, without indication for systemic therapy. Extensive surgery (laryngectomy, esophagectomy) was suggested, but patient refused and palliative care was started. Conclusion: Due to meticulous planning in an interdisciplinary team, we showed a successful airway management approach in this complicated case of critical airway compression secondary to a rare rhabdomyosarcoma, complicated by tracheal stent migration. Besides presenting our thoughts and considerations, we support exploring other possible approaches of this specific clinical problem.

Keywords: airway management, rhabdomyosarcoma, stent displacement, tracheal stenosis

Procedia PDF Downloads 86
1601 Long-Term Economic-Ecological Assessment of Optimal Local Heat-Generating Technologies for the German Unrefurbished Residential Building Stock on the Quarter Level

Authors: M. A. Spielmann, L. Schebek

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In order to reach the long-term national climate goals of the German government for the building sector, substantial energetic measures have to be executed. Historically, those measures were primarily energetic efficiency measures at the buildings’ shells. Advanced technologies for the on-site generation of heat (or other types of energy) often are not feasible at this small spatial scale of a single building. Therefore, the present approach uses the spatially larger dimension of a quarter. The main focus of the present paper is the long-term economic-ecological assessment of available decentralized heat-generating (CHP power plants and electrical heat pumps) technologies at the quarter level for the German unrefurbished residential buildings. Three distinct terms have to be described methodologically: i) Quarter approach, ii) Economic assessment, iii) Ecological assessment. The quarter approach is used to enable synergies and scaling effects over a single-building. For the present study, generic quarters that are differentiated according to significant parameters concerning their heat demand are used. The core differentiation of those quarters is made by the construction time period of the buildings. The economic assessment as the second crucial parameter is executed with the following structure: Full costs are quantized for each technology combination and quarter. The investment costs are analyzed on an annual basis and are modeled with the acquisition of debt. Annuity loans are assumed. Consequently, for each generic quarter, an optimal technology combination for decentralized heat generation is provided in each year of the temporal boundaries (2016-2050). The ecological assessment elaborates for each technology combination and each quarter a Life Cycle assessment. The measured impact category hereby is GWP 100. The technology combinations for heat production can be therefore compared against each other concerning their long-term climatic impacts. Core results of the approach can be differentiated to an economic and ecological dimension. With an annual resolution, the investment and running costs of different energetic technology combinations are quantified. For each quarter an optimal technology combination for local heat supply and/or energetic refurbishment of the buildings within the quarter is provided. Coherently to the economic assessment, the climatic impacts of the technology combinations are quantized and compared against each other.

Keywords: building sector, economic-ecological assessment, heat, LCA, quarter level

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1600 The Impact of Roof Thermal Performance on the Indoor Thermal Comfort in a Natural Ventilated Building Envelope in Hot Climatic Climates

Authors: J. Iwaro, A. Mwasha, K. Ramsubhag

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Global warming has become a threat of our time. It poses challenges to the existence of beings on earth, the built environment, natural environment and has made a clear impact on the level of energy and water consumption. As such, increase in the ambient temperature increases indoor and outdoor temperature level of the buildings which brings about the use of more energy and mechanical air conditioning systems. In addition, in view of the increased modernization and economic growth in the developing countries, a significant amount of energy is being used, especially those with hot climatic conditions. Since modernization in developing countries is rising rapidly, more pressure is being placed on the buildings and energy resources to satisfy the indoor comfort requirements. This paper presents a sustainable passive roof solution as a means of reducing energy cooling loads for satisfying human comfort requirements in a hot climate. As such, the study based on the field study data discusses indoor thermal roof design strategies for a hot climate by investigating the impacts of roof thermal performance on indoor thermal comfort in naturally ventilated building envelope small scaled structures. In this respect, the traditional concrete flat roof, corrugated galvanised iron roof and pre-painted standing seam roof were used. The experiment made used of three identical small scale physical models constructed and sited on the roof of a building at the University of the West Indies. The results show that the utilization of insulation in traditional roofing systems will significantly reduce heat transfer between the internal and ambient environment, thus reducing the energy demand of the structure and the relative carbon footprint of a structure per unit area over its lifetime. Also, the application of flat slab concrete roofing system showed the best performance as opposed to the metal roof sheeting alternative systems. In addition, it has been shown experimentally through this study that a sustainable passive roof solution such as insulated flat concrete roof in hot dry climate has a better cooling strength that can provide building occupant with a better thermal comfort, conducive indoor conditions and energy efficiency.

Keywords: building envelope, roof, energy consumption, thermal comfort

Procedia PDF Downloads 258