Search results for: natural compounds
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7601

Search results for: natural compounds

3491 Yields and Composition of the Gas, Liquid and Solid Fractions Obtained by Conventional Pyrolysis of Different Lignocellulosic Biomass Residues

Authors: María del Carmen Recio-Ruiz, Ramiro Ruiz-Rosas, Juana María Rosas, José Rodríguez-Mirasol, Tomás Cordero

Abstract:

Nowadays, fossil resources are main precursors for fuel production. Due to their contribution to the greenhouse effect and their future depletion, there is a constant search for environmentally friendly feedstock alternatives. Biomass residues constitute an interesting replacement for fossil resources because of their zero net CO₂ emissions. One of the main routes to convert biomass into energy and chemicals is pyrolysis. In this work, conventional pyrolysis of different biomass residues highly available such as almond shells, hemp hurds, olive stones, and Kraft lignin, was studied. In a typical experiment, the biomass was crushed and loaded into a fixed bed reactor under continuous nitrogen flow. The influence of temperature (400-800 ºC) and heating rate (10 and 20 ºC/min) on the pyrolysis yield and composition of the different fractions has been studied. In every case, the mass yields revealed that the solid fraction decreased with temperature, while liquid and gas fractions increased due to depolymerization and cracking reactions at high temperatures. The composition of every pyrolysis fraction was studied in detail. The results showed that the composition of the gas fraction was mainly CO, CO₂ when working at low temperatures, and mostly CH₄ and H₂at high temperatures. The solid fraction developed an incipient microporosity, with narrow micropore volume of 0.21 cm³/g. Regarding the liquid fraction, pyrolysis of almond shell, hemp hurds, and olive stones led mainly to a high content in aliphatic acids and furans, due to the high volatile matter content of these biomass (>74 %wt.), and phenols to a lesser degree, which were formed due to the degradation of lignin at higher temperatures. However, when Kraft lignin was used as bio-oil precursor, the presence of phenols was very prominent, and aliphatic compounds were also detected in a lesser extent.

Keywords: Bio-oil, biomass, conventional pyrolysis, lignocellulosic

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3490 Forced Migrants in Israel and Their Impact on the Urban Structure of Southern Neighborhoods of Tel Aviv

Authors: Arnon Medzini, Lilach Lev Ari

Abstract:

Migration, the driving force behind increased urbanization, has made cities much more diverse places to live in. Nearly one-fifth of all migrants live in the world’s 20 largest cities. In many of these global cities, migrants constitute over a third of the population. Many of contemporary migrants are in fact ‘forced migrants,’ pushed from their countries of origin due to political or ethnic violence and persecution or natural disasters. During the past decade, massive numbers of labor migrants and asylum seekers have migrated from African countries to Israel via Egypt. Their motives for leaving their countries of origin include ongoing and bloody wars in the African continent as well as corruption, severe conditions of poverty and hunger, and economic and political disintegration. Most of the African migrants came to Israel from Eritrea and Sudan as they saw Israel the closest natural geographic asylum to Africa; soon they found their way to the metropolitan Tel-Aviv area. There they concentrated in poor neighborhoods located in the southern part of the city, where they live under conditions of crowding, poverty, and poor sanitation. Today around 45,000 African migrants reside in these neighborhoods, and yet there is no legal option for expelling them due to dangers they might face upon returning to their native lands. Migration of such magnitude to the weakened neighborhoods of south Tel-Aviv can lead to the destruction of physical, social and human infrastructures. The character of the neighborhoods is changing, and the local population is the main victim. These local residents must bear the brunt of the failure of both authorities and the government to handle the illegal inhabitants. The extremely crowded living conditions place a heavy burden on the dilapidated infrastructures in the weakened areas where the refugees live and increase the distress of the veteran residents of the neighborhoods. Some problems are economic and some stem from damage to the services the residents are entitled to, others from a drastic decline in their standard of living. Even the public parks no longer serve the purpose for which they were originally established—the well-being of the public and the neighborhood residents; they have become the main gathering place for the infiltrators and a center of crime and violence. Based on secondary data analysis (for example: The Israel’s Population, Immigration and Border Authority, the hotline for refugees and migrants), the objective of this presentation is to discuss the effects of forced migration to Tel Aviv on the following tensions: between the local population and the immigrants; between the local population and the state authorities, and between human rights groups vis-a-vis nationalist local organizations. We will also describe the changes which have taken place in the urban infrastructure of the city of Tel Aviv, and discuss the efficacy of various Israeli strategic trajectories when handling human problems arising in the marginal urban regions where the forced migrant population is concentrated.

Keywords: African asylum seekers, forced migrants, marginal urban regions, urban infrastructure

Procedia PDF Downloads 248
3489 Appraisal of Humanitarian Supply Chain Risks Using Best-Worst Method

Authors: Ali Mohaghar, Iman Ghasemian Sahebi, Alireza Arab

Abstract:

In the last decades, increasing in human and natural disaster occurrence had very irreparable effects on human life. Hence, one of the important issues in humanitarian supply chain management is identifying and prioritizing the different risks and finding suitable solutions for encountering them at the time of disaster occurrence. This study is an attempt to provide a comprehensive review of humanitarian supply chain risks in a case study of Tehran Red Crescent Societies. For this purpose, Best-Worst method (BWM) has been used for analyzing the risks of the humanitarian supply chain. 22 risks of the humanitarian supply chain were identified based on the literature and interviews with four experts. According to BWM method, the importance of each risk was calculated. The findings showed that culture contexts, little awareness of people, and poor education system are the most important humanitarian supply chain risks. This research provides a useful guideline for managers so that they can benefit from the results to prioritize their solutions.

Keywords: Best-Worst Method, humanitarian logistics, humanitarian supply chain, risk management

Procedia PDF Downloads 308
3488 Native Language Identification with Cross-Corpus Evaluation Using Social Media Data: ’Reddit’

Authors: Yasmeen Bassas, Sandra Kuebler, Allen Riddell

Abstract:

Native language identification is one of the growing subfields in natural language processing (NLP). The task of native language identification (NLI) is mainly concerned with predicting the native language of an author’s writing in a second language. In this paper, we investigate the performance of two types of features; content-based features vs. content independent features, when they are evaluated on a different corpus (using social media data “Reddit”). In this NLI task, the predefined models are trained on one corpus (TOEFL), and then the trained models are evaluated on different data using an external corpus (Reddit). Three classifiers are used in this task; the baseline, linear SVM, and logistic regression. Results show that content-based features are more accurate and robust than content independent ones when tested within the corpus and across corpus.

Keywords: NLI, NLP, content-based features, content independent features, social media corpus, ML

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3487 A Global Perspective on Urban Environmental Problems in Developing Countries: The Case of Turkey

Authors: Nükhet Konuk, N. Gamze Turan, Yüksel Ardalı

Abstract:

Cities play a vital role in the social fabric of countries and in national and regional economic growth worldwide; however, the environmental effects of such growth need to be assessed and managed better. The critical and most immediate problems faced by cities of developing countries are the health impacts of urban pollution that derive from inadequate water, sanitation, drainage and solid waste services, poor urban and industrial waste management, and air pollution. As globalization continues, earth's natural processes transform local problems into international issues. The aim of this study is to provide a broad overview of the pollution from urban wastes and emissions in Turkey which is a developing country. It is aimed to underline the significance of reorganizing the institutional tools in a worldwide perspective in order to generate coherent solutions to urban problems, and to enhance urban quality.

Keywords: environmental pollution, developing countries, environmental degradation, urban environmental problems

Procedia PDF Downloads 324
3486 A Case Study of Kick Control in Tough Potohar Region

Authors: Iftikhar Raza

Abstract:

Well control is the management of the hazardous effects caused by the unexpected release of formation fluid, such as natural gas and/or crude oil, upon surface equipment of oil or gas drilling rigs and escaping into the atmosphere. Technically, oil well control involves preventing the formation fluid, usually referred to as kick, from entering into the wellbore during drilling. Oil well control is one of the most important aspects of drilling operations. Improper handling of kicks in oil well control can result in blowouts with very grave consequences, including the loss of valuable resources. Even though the cost of a blowout (as a result of improper/no oil well control) can easily reach several millions of US dollars, the monetary loss is not as serious as the other damages that can occur: irreparable damage to the environment, waste of valuable resources, ruined equipment, and most importantly, the safety and lives of personnel on the drilling rig. In this paper, case study of a well is discussed with field data showing the properties of the well. The whole procedure of controlling this well is illustrated in this which may be helpful for professional dealing with such kind of problems.

Keywords: kick control, kill sheet, oil well, gas drilling

Procedia PDF Downloads 502
3485 The Effect of Spatial Variability on Axial Pile Design of Closed Ended Piles in Sand

Authors: Cormac Reale, Luke J. Prendergast, Kenneth Gavin

Abstract:

While significant improvements have been made in axial pile design methods over recent years, the influence of soils natural variability has not been adequately accounted for within them. Soil variability is a crucial parameter to consider as it can account for large variations in pile capacity across the same site. This paper seeks to address this knowledge deficit, by demonstrating how soil spatial variability can be accommodated into existing cone penetration test (CPT) based pile design methods, in the form of layered non-homogeneous random fields. These random fields model the scope of a given property’s variance and define how it varies spatially. A Monte Carlo analysis of the pile will be performed taking into account parameter uncertainty and spatial variability, described using the measured scales of fluctuation. The results will be discussed in light of Eurocode 7 and the effect of spatial averaging on design capacities will be analysed.

Keywords: pile axial design, reliability, spatial variability, CPT

Procedia PDF Downloads 242
3484 Developing a Process and Cost Model for Xanthan Biosynthesis from Bioethanol Production Waste Effluents

Authors: Bojana Ž. Bajić, Damjan G. Vučurović, Siniša N. Dodić, Jovana A. Grahovac, Jelena M. Dodić

Abstract:

Biosynthesis of xanthan, a microbial polysaccharide produced by Xanthomonas campestris, is characterized by the possibility of using non-specific carbohydrate substrates, which means different waste effluents can be used as a basis for the production media. Potential raw material sources for xanthan production come from industries with large amounts of waste effluents that are rich in compounds necessary for microorganism growth and multiplication. Taking into account the amount of waste effluents generated by the bioethanol industry and the fact that it contains a high inorganic and organic load it is clear that they represent a potential environmental pollutants if not properly treated. For this reason, it is necessary to develop new technologies which use wastes and wastewaters of one industry as raw materials for another industry. The result is not only a new product, but also reduction of pollution and environmental protection. Biotechnological production of xanthan, which consists of using biocatalysts to convert the bioethanol waste effluents into a high-value product, presents a possibility for sustainable development. This research uses scientific software developed for the modeling of biotechnological processes in order to design a xanthan production plant from bioethanol production waste effluents as raw material. The model was developed using SuperPro Designer® by using input data such as the composition of raw materials and products, defining unit operations, utility consumptions, etc., while obtaining capital and operating costs and the revenues from products to create a baseline production plant model. Results from this baseline model can help in the development of novel biopolymer production technologies. Additionally, a detailed economic analysis showed that this process for converting waste effluents into a high value product is economically viable. Therefore, the proposed model represents a useful tool for scaling up the process from the laboratory or pilot plant to a working industrial scale plant.

Keywords: biotechnology, process model, xanthan, waste effluents

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3483 Broccoli Sprouts Powder Could Improve Metabolic and Liver Disorder-Induced by High-Fructose Corn Syrup

Authors: Zahra Bahadoran, Parvin Mirmiran, Hanieh-Sadat Ejtahed, Maryam Tohidi, Fereidoun Azizi

Abstract:

Background and Aim: Broccoli sprouts, rich source of bioactive compounds specially sulforaphane (SFN), have unique functional properties. This study was conducted to investigate the possible treatment effects of high-SFN broccoli sprouts powder on metabolic and liver disorders in rats fed with high-fructose corn syrup. Methods: Thirty-two male wistar rats, pretreated with an eight-week high-fructose diet (water containing 30% fructose), were randomly allocated into three groups: Baseline control (BC), control (C) (normal diet), and BSP-diet (normal diet+5% BSP). The duration of the study was 6 weeks. Biochemical measurements, liver weight and triglyceride content were evaluated and histopathological examination of liver was performed. Results: After 6-weeks, the liver weight was significantly lower in BSP group compared to controls (13.4 g vs. 11.4 g, P<0.05). After 6 weeks, a significant decrease was observed in fasting serum glucose, total cholesterol and triglyceride levels in both experimental groups (P<0.05). Compared to controls, serum levels of HDL-C were significantly higher in BSP group. The liver TG content in BSP compared to control group was lower (14.6 vs. 16.4 mg/mg tissue). The hepatic levels of alanine aminotransferase, aspartate aminotransferase and γ-glutamyl transferase had not considerable changes in the groups after the intervention period but the level of alkaline phosphatase significantly decreased in BSP group (P<0.05). The histopathological examination of liver confirmed a decrease lobular and portal inflammation and ballooning in BSP group compared to control. Conclusion: High-SFN broccoli sprouts powder has beneficials effect on metabolic and liver changes-induced by high fructose corn syrup.

Keywords: broccoli sprouts, metabolic disorders, fatty liver, food science

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3482 European and Scandinavian Tourists' Perceptions and Desire to Travel in Ranong Province

Authors: Wipanee Maen-In

Abstract:

The objectives of the research are i) to study the motivations of european and scandinavian tourists who select Ranong province as their destinations ii) to study their perception towards the Ranong Province and iii) to study the visitors’ decision making while visiting Ranong Province. The samples of the study are 220 European and Scandinavian tourists’ visitors at the Ranong by accidental sampling and in clouding online questionnaires for 53 sampling. The data analysis includes Percentage, Frequency and One-way ANOVA. The findings from the research are the motivation level of the visitors is considered prominent, the average score of the motivational factors ranks higher than the average of the pull factors to visit the Ranong province when considering the factors analysis, the research shows that the reason that most tourists visit the Ranong is for relaxation while the purity of the natural mineral hot springs is the most important pull factor.

Keywords: European and Scandinavian, Ranong province, tourists’ perceptions, visitors’ decision making

Procedia PDF Downloads 229
3481 Early Stage Suicide Ideation Detection Using Supervised Machine Learning and Neural Network Classifier

Authors: Devendra Kr Tayal, Vrinda Gupta, Aastha Bansal, Khushi Singh, Sristi Sharma, Hunny Gaur

Abstract:

In today's world, suicide is a serious problem. In order to save lives, early suicide attempt detection and prevention should be addressed. A good number of at-risk people utilize social media platforms to talk about their issues or find knowledge on related chores. Twitter and Reddit are two of the most common platforms that are used for expressing oneself. Extensive research has already been done in this field. Through supervised classification techniques like Nave Bayes, Bernoulli Nave Bayes, and Multiple Layer Perceptron on a Reddit dataset, we demonstrate the early recognition of suicidal ideation. We also performed comparative analysis on these approaches and used accuracy, recall score, F1 score, and precision score for analysis.

Keywords: machine learning, suicide ideation detection, supervised classification, natural language processing

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3480 Fundamentals and Techniques of Organic Agriculture in Egypt

Authors: Moustafa Odah

Abstract:

Organic Agriculture is a new and sustainable agricultural system that depends on the use of organic materials from within the farm resulting from crop residues and animal husbandry and the cultivation of leguminous crops, away from the use of chemicals in fertilization or pest resistance, which leads to the production of safe, clean and healthy food products with nutritional value high and free of chemicals enhance food security; it is also an agricultural model preserve natural resources by improving the fertility and soil characteristics, and enhance biodiversity and biological cycles; additionally, they preserve the environment from pollution, which makes it play an important role in providing food needs of the present generations and the preservation of the rights of the coming generations to achieve sustainable development.

Keywords: organic agriculture, food security and achieving sustainable development, fertilization or pest resistance, crop residues and animal husbandry and the cultivation of leguminous crops

Procedia PDF Downloads 78
3479 Coupled Field Formulation – A Unified Method for Formulating Structural Mechanics Problems

Authors: Ramprasad Srinivasan

Abstract:

Engineers create inventions and put their ideas in concrete terms to design new products. Design drivers must be established, which requires, among other things, a complete understanding of the product design, load paths, etc. For Aerospace Vehicles, weight/strength ratio, strength, stiffness and stability are the important design drivers. A complex built-up structure is made up of an assemblage of primitive structural forms of arbitrary shape, which include 1D structures like beams and frames, 2D structures like membranes, plate and shell structures, and 3D solid structures. Justification through simulation involves a check for all the quantities of interest, namely stresses, deformation, frequencies, and buckling loads and is normally achieved through the finite element (FE) method. Over the past few decades, Fiber-reinforced composites are fast replacing the traditional metallic structures in the weight-sensitive aerospace and aircraft industries due to their high specific strength, high specific stiffness, anisotropic properties, design freedom for tailoring etc. Composite panel constructions are used in aircraft to design primary structure components like wings, empennage, ailerons, etc., while thin-walled composite beams (TWCB) are used to model slender structures like stiffened panels, helicopter, and wind turbine rotor blades, etc. The TWCB demonstrates many non-classical effects like torsional and constrained warping, transverse shear, coupling effects, heterogeneity, etc., which makes the analysis of composite structures far more complex. Conventional FE formulations to model 1D structures suffer from many limitations like shear locking, particularly in slender beams, lower convergence rates due to material coupling in composites, inability to satisfy, equilibrium in the domain and natural boundary conditions (NBC) etc. For 2D structures, the limitations of conventional displacement-based FE formulations include the inability to satisfy NBC explicitly and many pathological problems such as shear and membrane locking, spurious modes, stress oscillations, lower convergence due to mesh distortion etc. This mandates frequent re-meshing to even achieve an acceptable mesh (satisfy stringent quality metrics) for analysis leading to significant cycle time. Besides, currently, there is a need for separate formulations (u/p) to model incompressible materials, and a single unified formulation is missing in the literature. Hence coupled field formulation (CFF) is a unified formulation proposed by the author for the solution of complex 1D and 2D structures addressing the gaps in the literature mentioned above. The salient features of CFF and its many advantages over other conventional methods shall be presented in this paper.

Keywords: coupled field formulation, kinematic and material coupling, natural boundary condition, locking free formulation

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3478 Motif Search-Aided Screening of the Pseudomonas syringae pv. Maculicola Genome for Genes Encoding Tertiary Alcohol Ester Hydrolases

Authors: M. L. Mangena, N. Mokoena, K. Rashamuse, M. G. Tlou

Abstract:

Tertiary alcohol ester (TAE) hydrolases are a group of esterases (EC 3.1.1.-) that catalyze the kinetic resolution of TAEs and as a result, they are sought-after for the production of optically pure tertiary alcohols (TAs) which are useful as building blocks for number biologically active compounds. What sets these enzymes apart is, the presence of a GGG(A)X-motif in the active site which appears to be the main reason behind their activity towards the sterically demanding TAEs. The genome of Pseudomonas syringae pv. maculicola (Psm) comprises a multitude of genes that encode esterases. We therefore, hypothesize that some of these genes encode TAE hydrolases. In this study, Psm was screened for TAE hydrolase activity using the linalyl acetate (LA) plate assay and a positive reaction was observed. As a result, the genome of Psm was screened for esterases with a GGG(A)X-motif using the motif search tool and two potential TAE hydrolase genes (PsmEST1 and 2, 1100 and 1000bp, respectively) were identified, PsmEST1 was amplified by PCR and the gene sequenced for confirmation. Analysis of the sequence data with the SingnalP 4.1 server revealed that the protein comprises a signal peptide (22 amino acid residues) on the N-terminus. Primers specific for the gene encoding the mature protein (without the signal peptide) were designed such that they contain NdeI and XhoI restriction sites for directional cloning of the PCR products into pET28a. The gene was expressed in E. coli JM109 (DE3) and the clones screened for TAE hydrolase activity using the LA plate assay. A positive clone was selected, overexpressed and the protein purified using nickel affinity chromatography. The activity of the esterase towards LA was confirmed using thin layer chromatography.

Keywords: hydrolases, tertiary alcohol esters, tertiary alcohols, screening, Pseudomonas syringae pv., maculicola genome, esterase activity, linalyl acetate

Procedia PDF Downloads 352
3477 Reducing Energy Consumption and GHG Emission by Integration of Flare Gas with Fuel Gas Network in Refinery

Authors: N. Tahouni, M. Gholami, M. H. Panjeshahi

Abstract:

Gas flaring is one of the most GHG emitting sources in the oil and gas industries. It is also a major way for wasting such an energy that could be better utilized and even generates revenue. Minimize flaring is an effective approach for reducing GHG emissions and also conserving energy in flaring systems. Integrating waste and flared gases into the fuel gas networks (FGN) of refineries is an efficient tool. A fuel gas network collects fuel gases from various source streams and mixes them in an optimal manner, and supplies them to different fuel sinks such as furnaces, boilers, turbines, etc. In this article we use fuel gas network model proposed by Hasan et al. as a base model and modify some of its features and add constraints on emission pollution by gas flaring to reduce GHG emissions as possible. Results for a refinery case study showed that integration of flare gas stream with waste and natural gas streams to construct an optimal FGN can significantly reduce total annualized cost and flaring emissions.

Keywords: flaring, fuel gas network, GHG emissions, stream

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3476 Recycling of Spent Mo-Co Catalyst for the Recovery of Molybdenum Using Cyphos IL 104

Authors: Harshit Mahandra, Rashmi Singh, Bina Gupta

Abstract:

Molybdenum is widely used in thermocouples, anticathode of X-ray tubes and in the production of alloys of steels. Molybdenum compounds are extensively used as a catalyst in petroleum-refining industries for hydrodesulphurization. Activity of the catalysts decreases gradually with time and are dumped as hazardous waste due to contamination with toxic materials during the process. These spent catalysts can serve as a secondary source for metal recovery and help to sort out environmental and economical issues. In present study, extraction and separation of molybdenum from a Mo-Co spent catalyst leach liquor containing 0.870 g L⁻¹ Mo, 0.341 g L⁻¹ Co, 0.422 ×10⁻¹ g L⁻¹ Fe and 0.508 g L⁻¹ Al in 3 mol L⁻¹ HCl has been investigated using solvent extraction technique. The extracted molybdenum has been finally recovered as molybdenum trioxide. Leaching conditions used were- 3 mol L⁻¹ HCl, 90°C temperature, solid to liquid ratio (w/v) of 1.25% and reaction time of 60 minutes. 96.45% molybdenum was leached under these conditions. For the extraction of molybdenum from leach liquor, Cyphos IL 104 [trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate] in toluene was used as an extractant. Around 91% molybdenum was extracted with 0.02 mol L⁻¹ Cyphos IL 104, and 75% of molybdenum was stripped from the loaded organic phase with 2 mol L⁻¹ HNO₃ at A/O=1/1. McCabe Thiele diagrams were drawn to determine the number of stages required for the extraction and stripping of molybdenum. According to McCabe Thiele plots, two stages are required for both extraction and stripping of molybdenum at A/O=1/1 which were also confirmed by countercurrent simulation studies. Around 98% molybdenum was extracted in two countercurrent extraction stages with no co-extraction of cobalt and aluminum. Iron was removed from the loaded organic phase by scrubbing with 0.01 mol L⁻¹ HCl. Quantitative recovery of molybdenum is achieved in three countercurrent stripping stages at A/O=1/1. Trioxide of molybdenum was obtained from strip solution and was characterized by XRD, FE-SEM and EDX techniques. Molybdenum trioxide due to its distinctive electrochromic, thermochromic and photochromic properties is used as a smart material for sensors, lubricants, and Li-ion batteries. Molybdenum trioxide finds application in various processes such as methanol oxidation, metathesis, propane oxidation and in hydrodesulphurization. It can also be used as a precursor for the synthesis of MoS₂ and MoSe₂.

Keywords: Cyphos IL 104, molybdenum, spent Mo-Co catalyst, recovery

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3475 Determination of the Cooling Rate Dependency of High Entropy Alloys Using a High-Temperature Drop-on-Demand Droplet Generator

Authors: Saeedeh Imani Moqadam, Ilya Bobrov, Jérémy Epp, Nils Ellendt, Lutz Mädler

Abstract:

High entropy alloys (HEAs), having adjustable properties and enhanced stability compared with intermetallic compounds, are solid solution alloys that contain more than five principal elements with almost equal atomic percentage. The concept of producing such alloys pave the way for developing advanced materials with unique properties. However, the synthesis of such alloys may require advanced processes with high cooling rates depending on which alloy elements are used. In this study, the micro spheres of different diameters of HEAs were generated via a drop-on-demand droplet generator and subsequently solidified during free-fall in an argon atmosphere. Such droplet generators can generate individual droplets with high reproducibility regarding droplet diameter, trajectory and cooling while avoiding any interparticle momentum or thermal coupling. Metallography as well as X-ray diffraction investigations for each diameter of the generated metallic droplets where then carried out to obtain information about the microstructural state. To calculate the cooling rate of the droplets, a droplet cooling model was developed and validated using model alloys such as CuSn%6 and AlCu%4.5 for which a correlation of secondary dendrite arm spacing (SDAS) and cooling rate is well-known. Droplets were generated from these alloys and their SDAS was determined using quantitative metallography. The cooling rate was then determined from the SDAS and used to validate the cooling rates obtained from the droplet cooling model. The application of that model on the HEA then leads to the cooling rate dependency and hence to the identification of process windows for the synthesis of these alloys. These process windows were then compared with cooling rates obtained in processes such as powder production, spray forming, selective laser melting and casting to predict if a synthesis is possible with these processes.

Keywords: cooling rate, drop-on-demand, high entropy alloys, microstructure, single droplet generation, X-ray Diffractometry

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3474 Reflector Arrangement Effect on Ultraviolet Lamp Performance by CFX Simulation

Authors: William Sidharta, Chin-Tu Lu

Abstract:

Fluorescent ultraviolet lamp generates ultraviolet light which is commonly used in industrial field with certain purposes especially for curing process. Due to the value of inefficiency, there are changes in energy from electrical energy to the heat energy and this would make a defect on the industrial product caused by high temperature of lamp tube during ultraviolet light emission. The condition of industrial scale is further worsening, since commonly using dozens of fluorescent ultraviolet lamps to support huge production process and then it will generates much more heat energy. The maximum temperature of fluorescent ultraviolet lamp will get affected by arranging the lamp tube reflector and this study presents CFX simulation results of the maximum lamp tube temperature with some different reflector arrangements on purely natural convection phenomena. There exists certain spaces value of the reflector and the lamp tube to obtaining lower maximum temperature of the fluorescent ultraviolet lamp.

Keywords: CFX simulation, fluorescent UV lamp, lamp tube reflector, UV light

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3473 Effect of Chemical Treatment on Mechanical Properties of KENAF Fiber Reinforced Unsaturated Polyester Composites

Authors: S. S. Abdullahi, H. Musa, A. A. Salisu, A. Ismaila, A. H. Birniwa

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In this study the treated and untreated kenaf fiber reinforced unsaturated polyester conventional composites were prepared. Hand lay-up technique was used with dump-bell shaped mold. The kenaf bast fiber was retted enzymatically, washed, dried and combed with a nylon brush. A portion of the kenaf fiber was mercerized and treated with benzoylchloride prior to composite fabrication. Untreated kenaf fiber was also used to prepare the composites to serve as control. The cured composites were subjected to various mechanical testes, such as hardness test, impact test and tensile strength test. The results obtained indicated an increase in all the parameters tested with the fiber treatment. This is because the lignin, hemi-celluloses, pectin and other impurities were removed during alkaline treatment (i.e mercerization). This shows that, the durability of the natural cellulosic fibers to different composite applications can be achieved via fiber treatments.

Keywords: composite, kenaf fibre, reinforce, retted

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3472 Extracts of Cola acuminata, Lupinus arboreus and Bougainvillea spectabilis as Natural Photosensitizers for Dye-Sensitized Solar Cells

Authors: M. L. Akinyemi, T. J. Abodurin, A. O. Boyo, J. A. O. Olugbuyiro

Abstract:

Organic dyes from Cola acuminata (C. acuminata), Lupinus arboreus (L. arboreus) and Bougainvillea spectabilis (B. spectabilis) leaves and their mixtures were used as sensitizers to manufacture dye-sensitized solar cells (DSSC). Photoelectric measurements of C. acuminata showed a short circuit current (Jsc) of 0.027 mA/ cm2, 0.026 mA/ cm2 and 0.018 mA/ cm2 with a mixture of mercury chloride and iodine (Hgcl2 + I); potassium bromide and iodine (KBr + I); and potassium chloride and iodine (KCl + I) respectively. The open circuit voltage (Voc) was 24 mV, 25 mV and 20 mV for the three dyes respectively. L. arboreus had Jsc of 0.034 mA/ cm2, 0.021 mA/ cm2 and 0.013 mA/ cm2; and corresponding Voc of 28 mV, 14.2 mV and 15 mV for the three electrolytes respectively. B. spectabilis recorded Jsc 0.023 mA/ cm2, 0.026 mA/ cm2 and 0.015 mA/ cm2; and corresponding Voc values of 6.2 mV, 14.3 mV and 4.0 mV for the three electrolytes respectively. It was observed that the fill factor (FF) was 0.140 for C. acuminata, 0.3198 for L. arboreus and 0.1138 for B. spectabilis. Internal conversions of 0.096%, 0.056% and 0.063% were recorded for three dyes when combined with (KBr + I) electrolyte. The internal efficiency of C. acuminata DSSC was highest in value.

Keywords: dye-sensitized solar cells, organic dye, C. acuminate, L. arboreus, B. spectabilis, dye mixture

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3471 Anti-Obesity Activity of Garcinia xanthochymus: Biochemical Characterization and In vivo Studies in High Fat Diet-Rat Model

Authors: Mahesh M. Patil, K. A. Anu-Appaiah

Abstract:

Overweight and obesity is a serious medical problem, increasing in prevalence, and affecting millions worldwide. Investigators have been trying from decades to articulate the burden of obesity and related risk factors. To answer this problem, we suggest a new therapeutic anti-obesity compounds from Garcinia xanthochymus fruit. However, there is little published scientific information on non-hydroxycitric acid Garcinia species. Our findings include biochemical characterization of the fruit; in vivo toxicity and bio-efficacy study of G. xanthochymus in high fat diet wistar rat model. We observed that Garcinia pericarp is a rich source of organic acids, polyphenols, mono- (40.63%) and poly-unsaturated fatty acids (16.45%; omega-3: 10.02%). Toxicological studies have showed that Garcinia is safe and had no observed adverse effect level up to 400 mg/kg/day. Body weight and food intake was significantly (P<0.05) reduced in oral gavage treated rats (sonicated Garcinia powder) in 13 weeks. Subcutaneous fat was significantly (P<0.05) reduced in Garcinia treated rats. Hepatocytes significantly (p<0.05) overexpressed sterol regulatory element binding protein 2, liver X receptor- α, liver X receptor- β, lipoprotein lipase and monoacylglycerol lipase. Fatty acid binding protein 1 and peroxisome proliferator activated receptor- α were down regulated as assessed by real time qPCR. Currently our research is focused on the adipocyte obesity related gene expressions, effect of Garcinia on 3T3-adipocyte cell lines and high fat diet induced mice model. This in vivo pre-clinical data suggests that G. xanthochymus may have clinical utility for the treatment of obesity. However, further studies are required to establish its potency.

Keywords: Garcinia xanthochymus, anti-obesity, high fat diet, real time qPCR

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3470 Combustion and Emission Characteristics in a Can-Type Combustion Chamber

Authors: Selvakuma Kumaresh, Man Young Kim

Abstract:

Combustion phenomenon will be accomplished effectively by the development of low emission combustor. One of the significant factors influencing the entire Combustion process is the mixing between a swirling angular jet (Primary Air) and the non-swirling inner jet (fuel). To study this fundamental flow, the chamber had to be designed in such a manner that the combustion process to sustain itself in a continuous manner and the temperature of the products is sufficiently below the maximum working temperature in the turbine. This study is used to develop the effective combustion with low unburned combustion products by adopting the concept of high swirl flow and motility of holes in the secondary chamber. The proper selection of a swirler is needed to reduce emission which can be concluded from the emission of Nox and CO2. The capture of CO2 is necessary to mitigate CO2 emissions from natural gas. Thus the suppression of unburned gases is a meaningful objective for the development of high performance combustor without affecting turbine blade temperature.

Keywords: combustion, emission, can-type combustion chamber, CFD, motility of holes, swirl flow

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3469 Bibliometric Analysis of the Impact of Funding on Scientific Development of Researchers

Authors: Ashkan Ebadi, Andrea Schiffauerova

Abstract:

Every year, a considerable amount of money is being invested on research, mainly in the form of funding allocated to universities and research institutes. To better distribute the available funds and to set the most proper R&D investment strategies for the future, evaluation of the productivity of the funded researchers and the impact of such funding is crucial. In this paper, using the data on 15 years of journal publications of the NSERC (Natural Sciences and Engineering research Council of Canada) funded researchers and by means of bibliometric analysis, the scientific development of the funded researchers and their scientific collaboration patterns will be investigated in the period of 1996-2010. According to the results it seems that there is a positive relation between the average level of funding and quantity and quality of the scientific output. In addition, whenever funding allocated to the researchers has increased, the number of co-authors per paper has also augmented. Hence, the increase in the level of funding may enable researchers to get involved in larger projects and/or scientific teams and increase their scientific output respectively.

Keywords: bibliometrics, collaboration, funding, productivity

Procedia PDF Downloads 279
3468 On the Framework of Contemporary Intelligent Mathematics Underpinning Intelligent Science, Autonomous AI, and Cognitive Computers

Authors: Yingxu Wang, Jianhua Lu, Jun Peng, Jiawei Zhang

Abstract:

The fundamental demand in contemporary intelligent science towards Autonomous AI (AI*) is the creation of unprecedented formal means of Intelligent Mathematics (IM). It is discovered that natural intelligence is inductively created rather than exhaustively trained. Therefore, IM is a family of algebraic and denotational mathematics encompassing Inference Algebra, Real-Time Process Algebra, Concept Algebra, Semantic Algebra, Visual Frame Algebra, etc., developed in our labs. IM plays indispensable roles in training-free AI* theories and systems beyond traditional empirical data-driven technologies. A set of applications of IM-driven AI* systems will be demonstrated in contemporary intelligence science, AI*, and cognitive computers.

Keywords: intelligence mathematics, foundations of intelligent science, autonomous AI, cognitive computers, inference algebra, real-time process algebra, concept algebra, semantic algebra, applications

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3467 Bioremediation of Arsenic from Industrially Polluted Soil of Vatva, Ahmedabad, Gujarat, India

Authors: C. Makwana, S. R. Dave

Abstract:

Arsenic is toxic to almost all living cells. Its contamination in natural sources affects the growth of microorganisms. The presence of arsenic is associated with various human disorders also. The attempt of this sort of study provides information regarding the performance of our isolated microorganisms in the presence of Arsenic, which have ample scope for bioremediation. Six isolates were selected from the polluted sample of industrial zone Vatva, Ahmedabad, Gujarat, India, out of which two were Thermophilic organisms. The thermophilic exopolysaccharide (EPS) producing Bacillus was used for microbial enhance oil recovery (MEOR) and in the bio beneficiation. Inorganic arsenic primarily exists in the form of arsenate or arsenite. This arsenic resistance isolate was capable of transforming As +3 to As+5. This isolate would be useful for arsenic remediation standpoint from aquatic systems. The study revealed that the thermophilic microorganism was growing at 55 degree centigrade showed considerable remediation property. The results on the growth and enzyme catalysis would be discussed in response to Arsenic remediation.

Keywords: aquatic systems, thermophilic, exopolysacchride, arsenic

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3466 Improvement on a CNC Gantry Machine Structure Design for Higher Machining Speed Capability

Authors: Ahmed A. D. Sarhan, S. R. Besharaty, Javad Akbaria, M. Hamdi

Abstract:

The capability of CNC gantry milling machines in manufacturing long components has caused the expanded use of such machines. On the other hand, the machines’ gantry rigidity can reduce under severe loads or vibration during operation. Indeed, the quality of machining is dependent on the machine’s dynamic behavior throughout the operating process. For this reason, this type of machines has always been used prudently and are non efficient. Therefore, they can usually be employed for rough machining and may not produce adequate surface finishing. In this paper, a CNC gantry milling machine with the potential to produce good surface finish has been designed and analyzed. The lowest natural frequency of this machine is 202 Hz at all motion amplitudes with a full range of suitable frequency responses. Meanwhile, the maximum deformation under dead loads for the gantry machine is 0.565µm, indicating that this machine tool is capable of producing higher product quality.

Keywords: frequency response, finite element, gantry machine, gantry design, static and dynamic analysis

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3465 The Death of Ruan Lingyu: Leftist Aesthetics and Cinematic Reality in the 1930s Shanghai

Authors: Chen Jin

Abstract:

This topic seeks to re-examine the New Women Incident in 1935 Shanghai from the perspective of the influence of leftist cinematic aesthetics on public discourse in 1930s Shanghai. Accordingly, an original means of interpreting the death of Ruan Lingyu will be provided. On 8th March 1935, Ruan Lingyu, the queen of Chinese silent film, committed suicide through overdosing on sleeping tablets. Her last words, ‘gossip is fearful thing’, interlinks her destiny with the protagonist she played in the film The New Women (Cai Chusheng, 1935). The coincidence was constantly questioned by the masses following her suicide, constituting the enduring question: ‘who killed Ruan Lingyu?’ Responding to this query, previous scholars primarily analyze the characters played by women -particularly new women as part of the leftist movement or public discourse of 1930s Shanghai- as a means of approaching the truth. Nevertheless, alongside her status as a public celebrity, Ruan Lingyu also plays as a screen image of mechanical reproduction. The overlap between her screen image and personal destiny attracts limited academic focus in terms of the effect and implications of leftist aesthetics of reality in relation to her death, which itself has provided impetus to this research. With the reconfiguration of early Chinese film theory in the 1980s, early discourses on the relationship between cinematic reality and consciousness proposed by Hou Yao and Gu Kenfu in the 1920s are integrated into the category of Chinese film ontology, which constitutes a transcultural contrast with the Euro-American ontology that advocates the representation of reality. The discussion of Hou and Gu overlaps cinematic reality with effect, which emphasizes the empathy of cinema that is directly reflected in the leftist aesthetics of the 1930s. As the main purpose of leftist cinema is to encourage revolution through depicting social reality truly, Ruan Lingyu became renowned for her natural and realistic acting proficiency, playing leading roles in several esteemed leftist films. The realistic reproduction and natural acting skill together constitute the empathy of leftist films, which establishes a dialogue with the virtuous female image within the 1930s public discourse. On this basis, this research considers Chinese cinematic ontology and affect theory as the theoretical foundation for investigating the relationship between the screen image of Ruan Lingyu reproduced by the leftist film The New Women and the female image in the 1930s public discourse. Through contextualizing Ruan Lingyu’s death within the Chinese leftist movement, the essay indicates that the empathy embodied within leftist cinematic reality limits viewers’ cognition of the actress, who project their sentiments for the perfect screen image on to Ruan Lingyu’s image in reality. Essentially, Ruan Lingyu is imprisoned in her own perfect replication. Consequently, this article states that alongside leftist anti-female consciousness, the leftist aesthetics of reality restricts women in a passive position within public discourse, which ultimately plays a role in facilitating the death of Ruan Lingyu.

Keywords: cinematic reality, leftist aesthetics, Ruan Lingyu, The New Women

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3464 Design and Development of a Bi-Leaflet Pulmonary Valve

Authors: Munirah Ismail, Joon Hock Yeo

Abstract:

Paediatric patients who require ventricular outflow tract reconstruction usually need valve construction to prevent valvular regurgitation. They would face problems like lack of suitable, affordable conduits and the need to undergo several operations in their lifetime due to the short lifespan of existing valves. Their natural growth and development are also of concern, even if they manage to receive suitable conduits. Current prosthesis including homografts, bioprosthetic valves, mechanical valves, and bovine jugular veins either do not have the long-term durability or the ability to adapt to the growth of such patients. We have developed a new design of bi-leaflet valve. This new technique accommodates patients’ annular size growth while maintaining valvular patency. A mock circulatory system was set up to assess the hemodynamic performance of the bi-leaflet pulmonary valve. It was found that the percentage regurgitation was acceptable and thus, validates this novel concept.

Keywords: bi-leaflet pulmonary valve, pulmonary heart valve, tetralogy of fallot, mock circulatory system

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3463 Effectiveness of Micania micrantha Extract on Woven Wound Dressing Materials

Authors: Md. Lutfor Rahman, Shaikh Md. Mominul Alam

Abstract:

Sometimes it causes external bleeding when human skin gets seriously injured. Natural source-based blood-clotting bandages are rarely used. The available chemically treated blood clotting materials sometimes show adverse effects and are not effective in quick recovery. Considering these facts, a new blood clotting woven wound dressing product has been developed which is a combination of Micania micrantha extract with woven fabric by absorption process. This product can be represented as an important addition to medical textiles. To develop a dressing material, Micania micrantha leaf juice was applied on bleached woven fabric, followed by sun drying. The effectiveness of this woven sample was tested on volunteers. It was observed that Micania micrantha containing woven sample has a tremendous effect over conventional wound dressing materials. This result is a milestone for the textile and medical sector.

Keywords: blood clotting, Micania micrantha, medical textiles, woven fabric

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3462 Understanding and Enhancing Ecotourism Opportunities through Education

Authors: V. Iakovoglou, G. N. Zaimes, M. P. Arraiza Bermúdez-Cañete, J. L. García, M. C. Giménez, C. Calderón-Guerrero, F. Ioras, I. Abrudan

Abstract:

A new fast growing trend in tourism is ecotourism, in which tourists visit natural ecosystems under low impact, non-consumptive and locally oriented activities. Through these activities species and habitats are maintained and typically, underdeveloped regions are emphasized. Ecotourism provides a great alternative, especially for rural and undeveloped area. At the same time, despite its many benefits, it also poses many risks for the naturally protected areas. If ecotourism is practiced improperly degradation and irreversible damages could be the unwanted result. In addition, the lack of MSc programs in the field of Ecotourism in Europe makes it a necessity to be developed. Such an MSc program is being implemented with the lead partner the Technical University of Madrid. The entire partnership has six Universities, seven SMEs and one National Park from seven different countries all over Europe. The MSc will have 10 educational modules that will be available online and will prepare professionals that will be able to implement ecotourism in a sustainable way. Only through awareness and education a sustainable ecotourism will be achieved in the protected areas of Europe.

Keywords: ERASMUS, MSc program, protected Areas, sustainability

Procedia PDF Downloads 450