Search results for: economic conditions

Authors: Elene Tatunashvili, Bun Chan, Philippe E. Nashar, Christopher S. P. McErlean

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The reduction of aryl diazonium salts is one of the most efficient ways to generate aryl radicals for use in a wide range of transformations, including Sandmeyer-type reactions, Meerwein arylations of olefins and Gomberg-Bachmann-Hey arylations of heteroaromatic systems. The aryl diazonium species can be reduced electrochemically, by UV irradiation, inner-sphere and outer-sphere single electron transfer processes (SET) from metal salts, SET from photo-excited organic catalysts or fragmentation of adducts with weak bases (acetate, hydroxide, etc.). This paper details an approach for the metal-free reduction of aryl diazonium salts, which facilitates the efficient synthesis of various aromatic compounds under exceedingly mild reaction conditions. By measuring the oxidation potential of a number of organic molecules, a series of nucleophiles were identified that reduce aryl diazonium salts via the addition-fragmentation mechanism. This approach leads to unprecedented operational simplicity: The reactions are very rapid and proceed in the open air; there is no need for external irradiation or heating, and the process is compatible with a large number of radical reactions. We illustrate these advantages by using the addition-fragmentation strategy to regioselectively arylate a series of heterocyclic compounds, to synthesize ketones by arylation of silyl enol ethers, and to synthesize benzothiophene and phenanthrene derivatives by radical annulation reactions.

Keywords: diazonium salts, hantzsch esters, oxygen, radical reactions, synthetic methods

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Authors: Alireza Ghadiri, Soheila Memarzadeh, Arash Ghadiri

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Heat pipes are efficient heat transfer devices for solar hot water heating systems. However, the effective downward transfer of solar energy in an integrated heat pipe system provides increased design and implementation options. There is a lack of literature about flat plate wicked assisted heat pipe solar collector, especially with the presence of finned water-cooled condenser wicked heat pipes for solar energy applications. In this paper, the consequence of incorporating fins arrays into the condenser region of screen mesh heat pipe solar collector is investigated. An experimental model and a transient theoretical model are conducted to compare the performances of the solar heating system at a different period of the year. A good agreement is shown between the model and the experiment. Two working fluids are investigated (water and methanol) and results reveal that water slightly outperforms methanol with a collector instantaneous efficiency of nearly 60%. That modest improvement is achieved by adding fins to the condenser region of the heat pipes. Results show that the collector efficiency increase as the number of fins increases (upon certain number) and reveal that the mesh number is an important factor which affect the overall collector efficiency. An optimal heat pipe mesh number of 100 meshes/in. With two layers appears to be favorable in such collectors for their design and operating conditions.

Keywords: heat pipe, solar collector, capillary limit, mesh number

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Authors: Thammanoon Raveepong, Craig Wheway

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Originating from a multifaceted research project beginning with the opening of the Green Market at Ban Laow sub-district, Kosum Phisai, Mahasarakham with the support of Kosum Phisai Governor. The project involves key stakeholders related to villagers who have become involved with linking local identity to a more global identity to help ameliorate falling agricultural incomes and casualised work. There have been fifteen formal meetings involving local government stakeholders that took place at the local university, local schools, a public meeting at Ban-Don-Toom and Village meeting shelters. These events hosted 176 local stakeholders consisting of the District Governor, 7 Chairpersons/Heads of the District Development Council, a Health Promotion group, District retired government staff, 4 sub-district local government members, the City Development Council, 2 representatives from Mahasarakham Provincial Culture Council, 4 principles of all local schools, 11 village heads, 15 scholars form local and national universities, 132 villagers and 4 staff from public relation units. The goal of the project was to initiate a variety of local projects including promotion of Local healthy food, farm/homestay accommodation, local uniqueness, Travel guides (in book form and guide youths) and the proposed development of community tourism with the aim to utilise local people and activities to tap into the growing alternative tourism market. This paper aims to document the progress thus far, and the challenges presented working with local communities that have lacked expertise in linking to the global economy to derive economic benefits for their communities.

Keywords: Community-based tourism, community participation, local identity, mahasarakham province

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Authors: P. N. Salini, B. Anish Kini, R. Ashalatha

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At signalized intersections with heterogeneous traffic, the percentage share of different vehicle categories have a bearing on the inter-vehicle space utilization, which eventually impacts the saturation flow. This paper analyzed the impact of the percentage share of various vehicle categories in the traffic stream on the saturation flow at signalized intersections by video graphing major intersections with varying geometry in Kerala, India. It was found that as the percentage share of two-wheelers increases, the saturation flow at signalized intersections increases and vice-versa for the percentage share of cars. The effect of bus blockage and parking maneuvers on the saturation flow were also studied. As the distance of bus blockage increases from the stop line, the effect on the saturation flow decreases, while with more buses stopping at the same bus stop, the saturation flow reduces further. The study revealed that with higher kerbside parking maneuvers on the upstream, the saturation flow reduces, and with an increase in the distance of the parking maneuver from the stop line, the effect on the saturation flow decreases. The adjustment factors for bus blockage due to bus stops within 75m downstream and parking maneuvers within 75m upstream of the intersection have been established for mixed traffic conditions. These adjustment factors could empower the urban planners, enforcement personnel and decision-makers to estimate the reduction in the capacity of signalized intersections for suggesting improvements in the form of parking restrictions/ bus stop relocation for existing intersections or make design changes for planned intersections.

Keywords: signalized intersection, saturation flow, adjustment factors, capacity

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Authors: Osamah S. Alanazi, Mohammad G. Kotbi, Mohammed O. AlFadil

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While renewable energy technology is developing in Saudi Arabia, and the ambitious 2030 vision encourages the shift towards more efficient and clean energy usage. The research on the application of geothermal resources in residential use for the Saudi Arabian context will contribute towards a more sustainable environment. This paper is a part of an ongoing master's thesis, which its main goal is to investigate the possibility of achieving a zero-carbon house in Riyadh by applying a ground-coupled system into a current sustainable house that uses a grid-tied solar system. The current house was built and designed by King Saud University for the 2018 middle east solar decathlon competition. However, it failed to reach zero-carbon operation due to the high cooling demand. This study will redesign and validate the house using Revit and Carriers Hourly Analysis 'HAP' software with the use of ordinary least square 'OLS' regression. After that, a ground source ventilation system will be designed using the 'GCV Tool' to reduce cooling loads. After the application of the ground source system, the new electrical loads will be compared with the current house. Finally, a simple economic analysis that includes the cost of applying a ground source system will be reported. The findings of this study will indicate the possibility and feasibility of reaching a zero-carbon house in Riyadh, Saudi Arabia, using a ground-coupled ventilation system. While cooling in the residential sector is the dominant energy consumer in the Gulf region, this work will certainly help in moving towards using renewable sources to meet those demands. This paper will be limited to highlight the literature review, the methodology of the research, and the expected outcome.

Keywords: renewable energy, zero-carbon houses, sustainable buildings, geothermal energy, solar PV, GCV Tool

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Authors: Esra Yaldız, Dicle Aydın

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Sustainability is a term that provides deciding about the future considering environment and investigates the harmony and balance between protection and usage of the resource. The main objective of sustainability is creating residential areas is nature compatible or providing continuance thereby adapting existing residential area to nature. In this context, historical and traditional areas must have utilized according to sustainability. Traditional housing texture are identified as a traditional architectural product has been designed based on this term. General characteristics of traditional housing within the context of sustainable architecture are their specific dynamics and components and their harmonisation of environment and nature. Owing to the fact that traditional housing texture harmonizes natural conditions of the region, topography, climate and their context, construction materials are provided from environment and traditional techniques and their forms are used and due to construction materials has natural insulation traditional housing create healthy and comfortable living environment, traditional housing is rather significant in terms of sustainable architecture. The basis of this study comprise the routers in traditional housing design in accordance with the principles of sustainability. These are, accommodating topography, climate, and geography, accessibility, structuring at the scale of human, utilization of green zones, unique to the region used construction materials, the form of construction, building envelope and space organization of dwelling. In this context, the purpose of this study is that vernacular architecture approaches of traditional housing textures which are in Central Anatolia Region Located in Anatolia are utilized with regard to sustainability.

Keywords: Anatolia, sustainability, traditional housing texture, vernacular architecture

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Authors: Moustafa Osman Mohammed

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This paper is mapping air quality model to engineering the industrial system that ultimately utilized in extensive range of energy systems, distribution resources, and end-user technologies. The model is determining long-range transport patterns contribution as area source can either traced from 48 hrs backward trajectory model or remotely described from background measurements data in those days. The trajectory model will be run within stable conditions and quite constant parameters of the atmospheric pressure at the most time of the year. Air parcel trajectory is necessary for estimating the long-range transport of pollutants and other chemical species. It provides a better understanding of airflow patterns. Since a large amount of meteorological data and a great number of calculations are required to drive trajectory, it will be very useful to apply HYPSLIT model to locate areas and boundaries influence air quality at regional location of Windsor. 2–days backward trajectories model at high and low concentration measurements below and upward the benchmark which was areas influence air quality measurement levels. The benchmark level will be considered as 30 (μg/m3) as the moderate level for Ontario region. Thereby, air quality model is incorporating a midpoint concept between biotic and abiotic components to broaden the scope of quantification impact. The later outcomes’ theories of environmental obligation suggest either a recommendation or a decision of what is a legislative should be achieved in mitigation measures of air emission impact ultimately.

Keywords: air quality, management systems, environmental impact assessment, industrial ecology, climate change

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Authors: Behzad Ahdiharab, Senol Baskaya, Tamer Calisir

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Heat exchangers are one of the most widely used systems in factories, refineries etc. In this study, natural convection heat transfer using nano-fluids in between two cylinders is numerically investigated. The inner and outer cylinders are kept at constant temperatures. One of the most important assumptions in the project is that the working fluid is non-Newtonian. In recent years, the use of nano-fluids in industrial applications has increased profoundly. In this study, nano-Newtonian fluids containing metal particles with high heat transfer coefficients have been used. All fluid properties such as homogeneity has been calculated. In the present study, solutions have been obtained under unsteady conditions, base fluid was water, and effects of various parameters on heat transfer have been investigated. These parameters are Rayleigh number (103 < Ra < 106), power-law index (0.6 < n < 1.4), aspect ratio (0 < AR < 0.8), nano-particle composition, horizontal and vertical displacement of the inner cylinder, rotation of the inner cylinder, and volume fraction of nanoparticles. Results such as the internal cylinder average and local Nusselt number variations, contours of temperature, flow lines are presented. The results are also discussed in detail. From the validation study performed it was found that a very good agreement exists between the present results and those from the open literature. It was found out that the heat transfer is always affected by the investigated parameters. However, the degree to which the heat transfer is affected does change in a wide range.

Keywords: heat transfer, circular space, non-Newtonian, nano fluid, computational fluid dynamics.

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Authors: Claudia Seabra, Elisabeth Kastenholz, José Luís Abrantes, Manuel Reis

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In a world of increasing mobility and global risks, terrorism has, in a perverse way, capitalized on contemporaneous society’s growing interest in travel to explore a world whose national boundaries and distances have decreased. Terrorists have identified the modern tourist flows originated from the economically more developed countries as new appealing targets so as to: i) call attention to the causes they defend and ii) destroy a country’s foundations of tourism, with the final aim of disrupting the economic and consequently social fabric of the affected countries. The present study analyses sensitivity towards risk and travel behaviors in international travel amongst a sample of 600 international tourists from 49 countries travelling by air. Specifically, the sample was segmented according to the Global Peace Index. This index defines country profiles regarding the levels of peace. The indicators used are established over three broad themes: i) ongoing domestic and international conflict; ii) societal safety and security; and iii) militarisation. Tourists were segmented, according to their country of origin, in different levels of peacefulness. Several facets of travel behavior were evaluated, namely motivations, attitude towards trip planning, quality perception and perceived value of the trip. Also factors related with risk perception were evaluated, specifically terrorism risk perception during the trip, unsafety sensation as well as importance attributed to safety in travel. Results contribute to our understanding of the role of previous exposure to the lack of peace and safety at home in the international tourists behaviors, which is further discussed in terms of tourism management and marketing implications which should particularly interest tourism services and destinations more affected by terrorism, war, political turmoil, crime and other safety risks.

Keywords: terrorism, tourism, safety, risk perception

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Authors: Guillaume Linassier, Morgan Balland, Hugo Pervier, Marie Pervier, David Hammond

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Atmospheric icing for turbojet is caused by ingestion of super-cooled water droplets. To prevent operability risks, manufacturer can implement ice protection systems. Thermal systems are commonly used for this purpose, but their activation can cause the formation of a water liquid film, that can freeze downstream the heated surface or even on other components. In the framework of STORM, a European project dedicated to icing physics in turbojet engines, a cascade rig representative of engine inlet blades was built and tested in an icing wind tunnel. This mock-up integrates two rows of blades, the upstream one being anti-iced using an electro-thermal device the downstream one being unheated. Under icing conditions, the anti-icing system is activated and set at power level to observe a liquid film on the surface and droplet re-emission at the trailing edge. These re-emitted droplets will impinge on the downstream row and contribute to ice accretion. A complete experimental database was generated, including the characterization of ice accretion shapes, and the characterization of electro-thermal anti-icing system (power limit for apparition of the runback water or ice accretion). These data will be used for validation of numerical tools for modeling thermal anti-icing systems in the scope of engine application, as well as validation of re-emission droplets model for stator parts.

Keywords: turbomachine, anti-icing, cascade rig, runback water

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Authors: Aida Rafat, Ramazan Kahraman, Mert Atilhan

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The aggressive corrosion behavior of conventional amine solvents is one of main barriers against large scale commerizaliation of amine absorption process for carbon capture application. Novel CO2 absorbents that exhibit minimal corrosivity against operation conditions are essential to lower corrosion damage and control and ensure more robustness in the capture plant. This work investigated corrosion behavior of carbon steel CS1018 in various CO2 absrobent solvents. The tested solvents included the classical amines MEA, DEA and MDEA, piperazine activated solvents MEA/PZ, MDEA/PZ and MEA/MDEA/PZ as well as mixtures of MEA and Room Temperature Ionic Liquids RTIL, namely MEA/[C4MIM][BF4] and MEA/[C4MIM][Otf]. Electrochemical polarization technique was used to determine the system corrosiveness in terms of corrosion rate and polarization behavior. The process parameters of interest were CO2 loading and solution temperature. Electrochemical resulted showed corrosivity order of classical amines at 40°C is MDEA> MEA > DEA wherase at 80°C corrosivity ranking changes to MEA > DEA > MDEA. Corrosivity rankings were mainly governed by CO2 absorption capacity at the test temperature. Corrosivity ranking for activated amines at 80°C was MEA/PZ > MDEA/PZ > MEA/MDEA/PZ. Piperazine addition seemed to have a dual advanatge in terms of enhancing CO2 absorption capacity as well as nullifying corrosion. For MEA/RTIL mixtures, the preliminary results showed that the partial repalcement of aqueous phase in MEA solution by the more stable nonvolatile RTIL solvents reduced corrosion rates considerably.

Keywords: corrosion, amines, CO2 capture, piperazine, ionic liquids

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Authors: Adrian Keith Caamino, Sina Shakibania, Lena Sunqvist-Öqvist, Jan Rosenkranz, Yousef Ghorbani

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Feldspar minerals are one of the main components of the earth’s crust. They are tectosilicate, meaning that they mainly contain aluminum and silicon. Besides aluminum and silicon, they contain either potassium, sodium, or calcium. Accordingly, feldspar minerals are categorized into three main groups: K-feldspar, Na-feldspar, and Ca-feldspar. In recent years, the trend to use K-feldspar has grown tremendously, considering its potential to produce potash and alumina. However, the feldspar minerals, in general, are difficult to decompose for the dissolution of their metallic components. Several methods, including intensive milling, leaching under elevated pressure and temperature, thermal pretreatment, and the use of corrosive leaching reagents, have been proposed to improve its low dissolving efficiency. In this study, as part of the POTASSIAL EU project, to overcome the low dissolution efficiency of the K-feldspar components, mechanical activation using intensive milling followed by leaching using hydrochloric acid (HCl) was practiced. Grinding operational parameters, namely time, rotational speed, and ball-to-sample weight ratio, were studied using the Taguchi optimization method. Then, the mineralogy of the grinded samples was analyzed using a scanning electron microscope (SEM) equipped with automated quantitative mineralogy. After grinding, the prepared samples were subjected to HCl leaching. In the end, the dissolution efficiency of the main elements and impurities of different samples were correlated to the mineralogical characterization results. K-feldspar component dissolution is correlated with ore mineralogy, which provides insight into how to best optimize leaching conditions for selective dissolution. Further, it will have an effect on purifying steps taken afterward and the final value recovery procedures

Keywords: K-feldspar, grinding, automated mineralogy, impurity, leaching

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Authors: Sareh Rajabi, Taha Anjamrooz, Salwa Bheiry

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Sustainability of construction projects is an important issue to be addressed since the sector will continue to be developed in the coming years, especially in developing countries. Thus, it is significant to discover approaches and solutions for improving sustainability. Currently, the construction industry is the largest consumer of natural resources. This is the same in other countries in the Gulf region, and the United Arab Emirates (UAE) has limited natural resources such as water, electricity, etc. Recently, the UAE has taken several actions in order to implement sustainable initiatives within its construction industry. Within the industry, the contractors’ role is significant in promoting sustainable development by taking the responsibility to minimize their negative impacts on the environment and society, and maximize their economic distribution. In this research, sustainability will be studied as an important key to bring competitive advantages to contracting organizations. The contractors should understand the need to improve their sustainable performance in order to expand their business competitiveness. Competitiveness at the construction project level refers to a contractor’s ability to compete for a project. There is less focus on how to improve contractors’ competitiveness by implementing sustainable construction practices. Based on an inclusive literature review on the relationship between sustainability performance and business competitiveness, this research will conduct a study of sustainable practice in the construction industry and the relationship between sustainability performance and business competitiveness in order to develop a framework for evaluating how contractors can improve their competitiveness in terms of more efficient processes, enhancements in productivity, and lower costs of compliance in order to reduce the initial project cost and obtain market opportunities in the UAE. The research findings will provide a framework that can be a useful guideline for contractors to develop their sustainability policy, strategy and practice for meeting the increased requirements for sustainable development in construction.

Keywords: sustainable construction practice, sustainability, competitiveness, construction industry, contractors

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Authors: Anupriya, Bikramjit Sinfh, Radhay Shyam

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In order to improve mixing phenomena and combustion processes in supersonic flow, the current work has concentrated on identifying the ideal cavity parameters using CFD ANSYS Fluent. Offset ratios (OR) and aft ramp angles () have been manipulated in simulations of several models, but the length-to-depth ratio has remained the same. The length-to-depth ratio of all cavity flows is less than 10, making them all open. Hydrogen fuel was injected into a supersonic air flow with a Mach number of 3.75 using a chamber with a 1 mm diameter and a transverse slot nozzle. The free stream had conditions of a pressure of 1.2 MPa, a temperature of 299K, and a Reynolds number of 2.07x107. This method has the ability to retain a flame since the cavity facilitates rapid mixing of fuel and oxidizer and decreases total pressure losses. The impact of the cavity on combustion efficiency and total pressure loss is discussed, and the results are compared to those of a model without a cavity. Both the mixing qualities and the combustion processes were enhanced in the model with the cavity. The overall pressure loss as well as the effectiveness of the combustion process both increase with the increase in the ramp angle to the rear. When OR is increased, however, resistance to the supersonic flow field is reduced, which has a detrimental effect on both parameters. For a given ramp height, larger pressure losses were observed at steeper ramp angles due to increased eddy-viscous turbulent flow and increased wall drag.

Keywords: total pressure loss, flame holder, supersonic combustion, combustion efficiency, cavity, nozzle

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Authors: Pooja Jain

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Art education is often ignored in syllabus of developing countries like India and in educational planning for development but now days Indian Art with a global recognition is becoming an integral part of the education at all levels. The term art, widely used in all parts of the modern world, carried varied significance in India as its meaning was continuously being extended, covering the many varieties of creative expression such as painting, sculpture, commercial art, design, poetry, music, dance, and architecture. Over the last 100 years Indian artists of all forms have evolved a wide variety of expressive styles. With the recommendations and initiatives by Government of India, Art Education has subsequently gained pace at the school level as a mandatory subject for all making a path way for students with a creative bend of mind. This paper investigates curriculum in various schools of the country at secondary and senior secondary levels along with some eminent institutions running the program. Findings depicted the role of art education and justified its importance primarily with commercial art being perceived to be essential for students learning skills for economic gain in their career ahead. With so many art colleges spread across India, emerging artists and designers are being trained and are creating art of infinite variety and style and have opened up many career avenues. Commercial Art being a plethora of artistic expressions has confidently come of age wherein a creative perception is mixed with an introspective imagination to bring out multi faceted career options with a significant future enveloped in art. Visual arts in education thus is an expanding field of result assured research.

Keywords: modern art, commercial art, introspective imagination, career

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Authors: J. Kazior, A. Szewczyk-Nykiel, T. Pieczonka, M. Laska

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Aluminium alloys are an important class of engineering materials for structural applications. This is due to the fact that these alloys have many interesting properties, namely, low density, high ratio of strength to density, good thermal and electrical conductivity, good corrosion resistance as well as extensive capabilities for shaping processes. In case of classical PM technology a particular attention should be paid to the selection of appropriate parameters of compacting and sintering processes and to keeping them. The latter need arises from the high sensitivity of aluminium based alloy powders on any fluctuation of technological parameters, in particular those related to the temperature-time profile and gas flow. Only then the desired sintered compacts with residual porosity may be produced. Except high mechanical properties, the other profitable properties of almost fully dense sintered components could be expected. Among them is corrosion resistance, rarely investigated on PM aluminium alloys. Thus, in the current study the Alumix 431/D commercial, press-ready grade powder was used for this purpose. Sintered compacts made of it in different conditions (isothermal sintering temperature, gas flow rate) were subjected to corrosion experiments in 0,1 M and 0,5 M NaCl solutions. The potentiodynamic curves were used to establish parameters characterising the corrosion resistance of sintered Alumix 431/D powder, namely, the corrosion potential, the corrosion current density, the polarization resistance, the breakdown potential. The highest value of polarization resistance, the lowest value of corrosion current density and the most positive corrosion potential was obtained for Alumix431/D powder sintered at 600°C and for highest protective gas flow rate.

Keywords: aluminium alloys, sintering, corrosion resistance, industry

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Authors: Umeora Chukwunonso Obiefuna

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The private sector in housing provision continually take steps towards addressing part of the problem of cushioning the effect of the housing shortage in Nigeria by establishing housing estates since the government alone cannot provide housing for everyone. This research examined and reported findings from research conducted on the state of repair of buildings in private housing estates in Enugu metropolis, Enugu state Nigeria. The objectives of the study were to examine the physical conditions of the building fabrics and appraise the performance of infrastructural services provided in the buildings. The questionnaire was used as a research instrument to elicit data from respondents. Stratified sampling of the estates based on building type was adopted as a sampling method for this study. Findings from the research show that the state of repair of most buildings require minor repairs to make them fit for habitation and sound to ensure the well-being of the residents. In addition, four independent variables from the nine independent variables investigated significantly explained residual variation in the dependent variable - state of repair of the buildings in the study area. These variables are: Average Monthly Income of Residents (AMIR), Length of Stay of the Residents in the estates (LSY), Type of Wall Finishes on the buildings (TWF), and Time Taken to Respond to Resident’s complaints by the estate managers (TTRC). With this, the linear model was established for predicting the state of repair of buildings in private housing estates in the study area. This would assist in identifying variables that are lucid in predicting the state of repair of the buildings.

Keywords: building, housing estate, private, repair

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Authors: Sajjad Hussain, Sabir Khan, Maria Del Pilar Taboada Sotomayor

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This work demonstrates the synthesis of magnetic molecularly imprinted polymers (MMIPs) for determination of a selected pesticide (ametryne) using high performance liquid chromatography (HPLC). Computational simulation can assist the choice of the most suitable monomer for the synthesis of polymers. The (MMIPs) were polymerized at the surface of Fe3O4@SiO2 magnetic nanoparticles (MNPs) using 2-vinylpyradine as functional monomer, ethylene-glycol-dimethacrylate (EGDMA) is a cross-linking agent and 2,2-Azobisisobutyronitrile (AIBN) used as radical initiator. Magnetic non-molecularly imprinted polymer (MNIPs) was also prepared under the same conditions without analyte. The MMIPs were characterized by scanning electron microscopy (SEM), Brunauer, Emmett and Teller (BET) and Fourier transform infrared spectroscopy (FTIR). Pseudo first order and pseudo second order model were applied to study kinetics of adsorption and it was found that adsorption process followed the pseudo first order kinetic model. Adsorption equilibrium data was fitted to Freundlich and Langmuir isotherms and the sorption equilibrium process was well described by Langmuir isotherm mode. The selectivity coefficients (α) of MMIPs for ametryne with respect to atrazine, ciprofloxacin and folic acid were 4.28, 12.32, and 14.53 respectively. The spiked recoveries ranged between 91.33 and 106.80% were obtained. The results showed high affinity and selectivity of MMIPs for pesticide ametryne in the food samples.

Keywords: molecularly imprinted polymer, pesticides, magnetic nanoparticles, adsorption

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Authors: Tsetsegmaa A., Bayarsuren B., Altantsetseg Ts.

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To make the best decision on reducing harmful emissions from buses, we need to have a clear understanding of the current state of their actual emissions. The emissions from city buses running on high sulfur fuel, particularly particulate matter (PM) and nitrogen oxides (NOx) from the exhaust gases of conventional diesel engines, have been studied and measured with and without diesel particulate filter (DPF) in Ulaanbaatar city. The study was conducted by using the PEMS (Portable Emissions Measurement System) and gravimetric method in real traffic conditions. The obtained data were used to determine the actual emission rates and to evaluate the effectiveness of the selected particulate filters. Actual road and daily PM emissions from city buses were determined during the warm and cold seasons. A bus with an average daily mileage of 242 km was found to emit 166.155 g of PM into the city's atmosphere on average per day, with 141.3 g in summer and 175.8 g in winter. The actual PM of the city bus is 0.6866 g/km. The concentration of NOx in the exhaust gas averages 1410.94 ppm. The use of DPF reduced the exhaust gas opacity of 24 buses by an average of 97% and filtered a total of 340.4 kg of soot from these buses over a period of six months. Retrofitting an old conventional diesel engine with cassette-type silicon carbide (SiC) DPF, despite the laboriousness of cleaning, can significantly reduce particulate matter emissions. Innovation: First comprehensive road PM and NOx emission dataset and actual road emissions from public buses have been identified. PM and NOx mathematical model equations have been estimated as a function of the bus technical speed and engine revolution with and without DPF.

Keywords: conventional diesel, silicon carbide, real-time onboard measurements, particulate matter, diesel retrofit, fuel sulphur

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Authors: Mohd A. Azizan, Mohd Z. Zali

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It is well established that exposure to vibration has an adverse effect on human health, comfort, and performance. However, there is little quantitative knowledge on performance combined with drowsiness level during vibration exposure. This paper reports a study investigating the influence of vibration amplitude on seated occupant reaction time and drowsiness level. Eighteen male volunteers were recruited for this experiment. Before commencing the experiment, total transmitted acceleration measured at interfaces between the seat pan and seatback to human body was adjusted to become 0.2 ms-2 r.m.s and 0.4 ms-2 r.m.s for each volunteer. Seated volunteers were exposed to Gaussian random vibration with frequency band 1-15 Hz at two level of amplitude (low vibration amplitude and medium vibration amplitude) for 20-minutes in separate days. For the purpose of drowsiness measurement, volunteers were asked to complete 10-minutes PVT test before and after vibration exposure and rate their subjective drowsiness by giving score using Karolinska Sleepiness Scale (KSS) before vibration, every 5-minutes interval and following 20-minutes of vibration exposure. Strong evidence of drowsiness was found as there was a significant increase in reaction time and number of lapse following exposure to vibration in both conditions. However, the effect is more apparent in medium vibration amplitude. A steady increase of drowsiness level can also be observed in KSS in all volunteers. However, no significant differences were found in KSS between low vibration amplitude and medium vibration amplitude. It is concluded that exposure to vibration has an adverse effect on human alertness level and more pronounced at higher vibration amplitude. Taken together, these findings suggest a role of vibration in promoting drowsiness, especially at higher vibration amplitude.

Keywords: drowsiness, human vibration, karolinska sleepiness scale, psychomotor vigilance test

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Authors: Dylan Yanano Mangani, Theodore Nkadimeng Mahosi

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Soon after independence on 18th April 1980, Zimbabwe’s foreign policy was shaped by the realities on the ground, which saw the country managing a sound relationship with both the Capitalist West and the Communist Eastern blocs. The post-independence foreign policy was therefore premised on security concerns illuminated by the Cold War era. This was one the reasons President Robert Mugabe adopted a policy of reconciliation and this earned his government recognition on the international platform. However, in Southern Africa apartheid South Africa was still the vanguard of capitalism and oppression such that she posed a serious threat to the newly born Zimbabwean nation which necessitated that Zimbabwe position herself both in the region and the continent to counter potential internal stability from within. Irrespective of how the international community viewed the country’s foreign policy Zimbabwe has continued to influence regional, continental and world geo-politics, especially on behalf of the developing nations. This raises a question why as a result of its foreign policy the country is now regarded a pariah state, especially some Western countries which used to applaud its political economic policies immediately after independence. Therefore, this study argues that the political economy of Zimbabwe had a far-reaching bearing on its foreign policy. For this reason, the problem necessitates the investigation of Zimbabwe’s foreign policy perspectives in Southern Africa since the turn of the 1990s. Two main theories which are Realism, Afro-centrism inform the study as an attempt to understand Zimbabwe’s foreign policy paradigm shift and perhaps provide answers to the objectives raised. The research therefore employs a qualitative approach where the conceptual nature of the study into the foreign policy of Zimbabwe is largely desktop research. However, the nature of the study will also require that oral interviews are conducted to substantiate some of the arguments advanced.

Keywords: cold war set up, foreign policy, look east policy, pan-africanism, post 2000 period, Southern Africa, Zimbabwe

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Authors: Meron Okbandrias

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The South African formal economy is rule-based economy, unlike most African and Asian markets. It has a highly developed financial market. In such a market, foreign migrants have dominated the small or spaza shops that service the poor. They are highly competitive and capture significant market share in South Africa. This paper analyses the factors that assisted the foreign migrants in having a competitive age. It does that by interviewing Somali, Bangladesh, and Ethiopian shop owners in Cape Town analysing the data through a narrative analysis. The paper also analyses the 2019 South African consumer report. The three migrant nationalities mentioned above dominate the spaza shop business and have significant distribution networks. The findings of the paper indicate that family, ethnic, and nationality based network, in that order of importance, form bases for a relationship-based business network that has trust as its mainstay. Therefore, this network ensures the pooling of resources and abiding by certain principles outside the South African rule-based system. The research identified practises like bulk buying within a community of traders, sharing information, buying from a within community distribution business, community based transportation system and providing seed capital for people from the community to start a business is all based on that relationship-based system. The consequences of not abiding by the rules of these networks are social and economic exclusion. In addition, these networks have their own commercial and social conflict resolution mechanisms aside from the South African justice system. Network theory and relationship based systems theory form the theoretical foundations of this paper.

Keywords: migrant, spaza shops, relationship-based system, South Africa

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Authors: Binod C. Agrawal

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In modern history, industrial and media merchandising in South Asia from East Asia, Europe, United States and other countries of the West is over 200 years old. Hence, continued external technology and media exposure is not a new experience in multi-lingual and multi religious South Asia which evolved cultural means to withstand structural change. In the post-World War II phase, media exposure especially of telecommunication, film, Internet, radio, print media and television have increased manifold. South Asia did not lose any time in acquiring and adopting digital media accelerated by chip revolution, computer and satellite communication. The penetration of digital media and utilization are exceptionally high though the spread has an unequal intensity, use and effects. The author argues that industrial and media products are “cultural products” apart from being “technological products”; hence their influences are most felt in the cultural domain which may lead to blunting of unique cultural specifics in the multi-cultural, multi-lingual and multi religious South Asia. Social scientists, political leaders and parents have voiced concern of “Cultural domination”, “Digital media colonization” and “Westernization”. Increased digital media access has also opened up doors of pornography and other harmful information that have sparked fresh debates and discussions about serious negative, harmful, and undesirable social effects especially among youth. Within ‘techno-social’ perspective, based on recent research studies, the paper aims to describe and analyse possible socio-economic change due to digital media penetration. Further, analysis supports the view that the ancient multi-lingual and multi-religious cultures of South Asia due to inner cultural strength may sustain without setting in a process of irreversible structural changes in South Asia.

Keywords: cultural sustainability, digital media effects, digital media impact in South Asia, social change in South Asia

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Authors: Cheong Hyeon Oh, Dongho Nam, Byungsik Kim

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Due to the recent climate change, flood damage caused by local floods and typhoons has frequently occurred, the incidence rate and intensity of wildfires are greatly increased due to increased temperatures and changes in precipitation patterns. Wildfires cause primary damage, such as loss of forest resources, as well as secondary disasters, such as landslides, floods, and debris flow. In many countries around the world, damage and economic losses from secondary damage are occurring as well as the direct effects of forest fires. Therefore, in this study, the Rainfall-Runoff model(S-RAT) was used for the wildfire affected areas in Gangneung and Goseong, which occurred on April 2019, when the stability of vegetation and soil were destroyed by wildfires. Rainfall data from Typhoon Rusa were used in the S-RAT model, and flood discharge was calculated according to changes in land cover before and after wildfire damage. The results of the calculation showed that flood discharge increased significantly due to changes in land cover, as the increase in flood discharge increases the possibility of the occurrence of the debris flow and the extent of the damage, the debris flow height and range were calculated before and after forest fire using RAMMS. The analysis results showed that the height and extent of damage increased after wildfire, but the result value was underestimated due to the characteristics that using DEM and maximum flood discharge of the RAMMS model. This research was supported by a grant(2017-MOIS31-004) from Fundamental Technology Development Program for Extreme Disaster Response funded by Korean Ministry of Interior and Safety (MOIS). This paper work (or document) was financially supported by Ministry of the Interior and Safety as 'Human resoure development Project in Disaster management'.

Keywords: wildfire, debris flow, land cover, rainfall-runoff meodel S-RAT, RAMMS, height

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Authors: H. E. Ferrari, R. Farengo, C. F. Clauser

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Tungsten (W) will be used in ITER as one of the plasma facing components (PFCs). The W could migrate to the plasma center. This could have a potentially deleterious effect on plasma confinement. Electron cyclotron resonance heating (ECRH) can be used to prevent W accumulation. We simulated a series of H mode discharges in ASDEX U with PFC containing W, where central ECRH was used to prevent W accumulation in the plasma center. The experiments showed that the W density profiles were flat after a sawtooth crash, and become hollow in between sawtooth crashes when ECRH has been applied. It was also observed that a saturated kink mode was active in these conditions. We studied the effect of saturated kink like instabilities on the redistribution of W impurities. The kink was modeled as the sum of a simple analytical equilibrium (large aspect ratio, circular cross section) plus the perturbation produced by the kink. A numerical code that follows the exact trajectories of the impurity ions in the total fields and includes collisions was employed. The code is written in Cuda C and runs in Graphical Processing Units (GPUs), allowing simulations with a large number of particles with modest resources. Our simulations show that when the W ions have a thermal velocity distribution, the kink has no effect on the W density. When we consider the plasma rotation, the kink can affect the W density. When the average passing frequency of the W particles is similar to the frequency of the kink mode, the expulsion of W ions from the plasma core is maximum, and the W density shows a hollow structure. This could have implications for the mitigation of W accumulation.

Keywords: impurity transport, kink instability, tungsten accumulation, tungsten dynamics

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Authors: Houria Rezala, Jose Luis Valverde, Amaya Romero, Alessandra Molinari, Andrea Maldotti

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A pillared montmorillonite containing iron doped titania (Fe/Ti-PILC) has been prepared from a natural clay. This material has been characterized by X-ray diffraction, nitrogen adsorption, temperature programmed desorption of ammonia, inductively coupled plasma atomic emission spectroscopy, atomic absorption, and diffuse reflectance UV-VIS spectroscopy. The layer structure of Fe/Ti-PILC resulted to be ordered with an insertion of pillars, which caused a slight increase in the basal spacing of the clay. Its specific surface area was about three times larger than that of the parent Na-montmorillonite due principally to the creation of a remarkable microporous network. The doped material was a robust photocatalyst able to oxidize liquid alkyl aromatics to the corresponding carbonylic derivatives, using O2 as the oxidizing species, at mild pressure and temperature conditions. Accumulation of valuable carbonylic derivatives was possible since their over-oxidation to carbon dioxide was negligible. Fe/Ti-PILC was able to discriminate between toluene and cyclohexane in favor of the aromatic compound with an efficiency that is about three times higher than that of titanium pillared clays (Ti-PILC). It is likely that the addition of iron favored the formation of new acid sites able to interact with the aromatic substrate. Iron doping caused a significant TiO2 visible light-induced activity (wavelength > 400 nm) with only minor negative effects on its performance under UV-light irradiation (wavelength > 290 nm).

Keywords: alkyl aromatics oxidation, heterogeneous photocatalysis, iron doping, pillared clays

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Authors: K. Ravi, Sabu Subhash

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Densely compacted bentonite or bentonite–sand mixture has been identified as a suitable buffer in the deep geological repository (DGR) for the safe disposal of high-level nuclear waste (HLW) due to its favourable physicochemical and hydro-mechanical properties. The addition of sand to the bentonite enhances the thermal conductivity and compaction properties and reduces the drying shrinkage of the buffer material. The buffer material may undergo cyclic wetting and drying upon ingress of groundwater from the surrounding rock mass and from evaporation due to high temperature (50–210 °C) derived from the waste canister. The cycles of changes in temperature may result in thermal history, and the hydro-mechanical properties of the buffer material may be affected. This paper examines the influence of thermal history on the undrained shear strength of bentonite and bentonite-sand mixture. Bentonite from Rajasthan state and sand from the Assam state of India are used in this study. The undrained shear strength values are obtained by conducting unconfined compressive strength (UCS) tests on cylindrical specimens (dry densities 1.30 and 1.5 Mg/m3) of bentonite and bentonite-sand mixture consisting of 30 % bentonite+ 70 % sand. The specimens are preheated at temperatures varying from 50-150 °C for one, two and four hours in hot air oven. The results indicate that the undrained shear strength is increased by the thermal history of the buffer material. The specimens of bentonite-sand mixture exhibited more increase in strength compared to the pure bentonite specimens. This indicates that the sand content of the mixture plays a vital role in taking the thermal stresses of the bentonite buffer in DGR conditions.

Keywords: bentonite, deep geological repository, thermal history, undrained shear strength

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Authors: Raana Babadi Fathipour

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Biofilms, those intricate structures of microbial aggregation that emerge as microorganisms adhere to animate or inanimate surfaces, possess an innate capacity to shield their inhabitants from adversities within the environment whilst fortifying their endurance against antimicrobial agents. This remarkable aspect facilitates the persistence and virulence of said microorganisms, establishing biofilm formation as an integral component of bacterial survival mechanisms. However, should foodborne pathogens adopt this mode of existence, the potentiality for foodborne disease infections becomes alarmingly intensified—an alarming prospect that harbors significant public health hazards and engenders deleterious economic ramifications. Thus, due to these consequences lurking on the horizon, extensive research concentrating upon comprehending biofilms and devising efficacious removal strategies assumes a position imbued with paramount importance within the realm of the food industry. The problem of food waste resulting from spoilage in the food industry continues to present a widespread challenge to both environmental sustainability and the security of our food supplies. In this comprehensive analysis, we delve into the formation of bacterial biofilms, highlighting the specific issues they pose within the realm of food production. Additionally, we provide an overview of various types of common foodborne pathogens that tend to thrive in these biofilms. Furthermore, we summarize existing strategies aimed at tackling or managing detrimental bacterial biofilm growth. We also introduce contemporary approaches that show promise in terms of controlling this issue and highlight their potential for further advancement. Ultimately, our focus lies on outlining prospects for future development as they pertain specifically to combatting bacterial biofilms within the field.

Keywords: foodborne pathogens, food safety, biofilm, resistance, quorum-sensing

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Authors: Hubert Feiglstorfer

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Due to its location in a transition zone from the Pannonian to the pre-Alpine region, the east of Austria shows a small-scale diversity in the regional development of certain vernacular building techniques. In this article the relationship between natural building material resources, topography and climate will be examined. Besides environmental preconditions, social and economic historical factors have developed different construction techniques within certain regions in the Weinviertel and Burgenland, the two eastern federal states of Austria. But even within these regions, varying building techniques were found, due to the locally different use of raw materials like wood, stone, clay, lime, or organic fibres. Within these small-scale regions, building traditions were adapted over the course of time due to changes in the use of the building material, for example from wood to brick or from wood to earth. The processing of the raw materials varies from region to region, for example as rammed earth, cob, log, or brick construction. Environmental preconditions cross national borders. For that reason, developments in the neighbouring countries, the Czech Republic, Slovakia, Hungary and Slovenia are included in this analysis. As an outcome of this research a map was drawn which shows the interrelation between locally available building materials, topography, climate and local building techniques? As a result of this study, which covers the last 300 years, one can see how the local population used natural resources very sensitively adapted to local environmental preconditions. In the case of clay, for example, changes of proportions of lime and particular minerals cause structural changes that differ from region to region. Based on material analyses in the field of clay mineralogy, on ethnographic research, literature and archive research, explanations for certain local structural developments will be given for the first time over the region of East Austria.

Keywords: European crafts, material culture, architectural history, earthen architecture, earth building history

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Authors: Qasar Saleem

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The aim of this project was to synthesize and analyze Polylactic acid-grafted TiO2 nanocomposite. When dispersed at the nanoscale TiO2 can behave as see through transparent UV filters and thermomechanical materials. The synthesis plan involved three stages. First, dispersion of TiO2 white powder in water/ethanol solvent system. Second grafting TiO2 surface by oligomers of lactic acid aimed at changing its surface features. Third polymerization of lactic acid monomer with grafted TiO2 in the presence of anhydrous stannous chloride as a catalyst. Polylactic acid grafted-TiO2 nanocomposite was synthesized by melt polycondensation in situ of lactic acid onto titanium oxide (TiO2) nanoparticles surface. The product was characterized by TGA, DSC, FTIR, and UV analysis and degradation observation. An idea regarding bonds between the grafting polymer and surface modified titanium oxide nanoparticles. Characteristics peaks of Ti–carbonyl bond, the related intensities of the Fourier transmission absorption peaks of graft composite, the melt and decomposition behavior stages of Polylactic acid-grafted TiO2 nanocomposite convinced that oligomers of polylactic acid were chemically bonded on the surface of TiO2 nanoparticles. Through grafting polylactic acid, the Polylactic acid grafted -TiO2 sample shown good absorption in UV region and degradation behavior under normal atmospheric conditions. Regaining transparency of degraded white opaque Polylactic acid-grafted TiO2 nanocomposite on heating was another character. Polylactic acid-grafted TiO2 nanocomposite will be a potential candidate in future for biomedical, UV shielding and environment friendly material.

Keywords: condensation, nanocomposites, oligomers, polylactic

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