Search results for: highly pathogenic avian influenza (HPAI)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4866

Search results for: highly pathogenic avian influenza (HPAI)

1866 Agricultural Land Suitability Analysis of Kampe-Omi Irrigation Scheme Using Remote Sensing and Geographic Information System

Authors: Olalekan Sunday Alabi, Titus Adeyemi Alonge, Olumuyiwa Idowu Ojo

Abstract:

Agricultural land suitability analysis and mapping play an imperative role for sustainable utilization of scarce physical land resources. The objective of this study was to prepare spatial database of physical land resources for irrigated agriculture and to assess land suitability for irrigation and developing suitable area map of the study area. The study was conducted at Kampe-Omi irrigation scheme located at Yagba West Local Government Area of Kogi State, Nigeria. Temperature and rainfall data of the study area were collected for 10 consecutive years (2005-2014). Geographic Information System (GIS) techniques were used to develop irrigation land suitability map of the study area. Attribute parameters such as the slope, soil properties, topography of the study area were used for the analysis. The available data were arranged, proximity analysis of Arc-GIS was made, and this resulted into five mapping units. The final agricultural land suitability map of the study area was derived after overlay analysis. Based on soil composition, slope, soil properties and topography, it was concluded that; Kampe-Omi has rich sandy loam soil, which is viable for agricultural purpose, the soil composition is made up of 60% sand and 40% loam. The land-use pattern map of Kampe-Omi has vegetal area and water-bodies covering 55.6% and 19.3% of the total assessed area respectively. The landform of Kampe-Omi is made up of 41.2% lowlands, 37.5% normal lands and 21.3% highlands. Kampe-Omi is adequately suitable for agricultural purpose while an extra of 20.2% of the area is highly suitable for agricultural purpose making 72.6% while 18.7% of the area is slightly suitable.

Keywords: remote sensing, GIS, Kampe–Omi, land suitability, mapping

Procedia PDF Downloads 183
1865 High Resolution Sandstone Connectivity Modelling: Implications for Outcrop Geological and Its Analog Studies

Authors: Numair Ahmed Siddiqui, Abdul Hadi bin Abd Rahman, Chow Weng Sum, Wan Ismail Wan Yousif, Asif Zameer, Joel Ben-Awal

Abstract:

Advances in data capturing from outcrop studies have made possible the acquisition of high-resolution digital data, offering improved and economical reservoir modelling methods. Terrestrial laser scanning utilizing LiDAR (Light detection and ranging) provides a new method to build outcrop based reservoir models, which provide a crucial piece of information to understand heterogeneities in sandstone facies with high-resolution images and data set. This study presents the detailed application of outcrop based sandstone facies connectivity model by acquiring information gathered from traditional fieldwork and processing detailed digital point-cloud data from LiDAR to develop an intermediate small-scale reservoir sandstone facies model of the Miocene Sandakan Formation, Sabah, East Malaysia. The software RiScan pro (v1.8.0) was used in digital data collection and post-processing with an accuracy of 0.01 m and point acquisition rate of up to 10,000 points per second. We provide an accurate and descriptive workflow to triangulate point-clouds of different sets of sandstone facies with well-marked top and bottom boundaries in conjunction with field sedimentology. This will provide highly accurate qualitative sandstone facies connectivity model which is a challenge to obtain from subsurface datasets (i.e., seismic and well data). Finally, by applying this workflow, we can build an outcrop based static connectivity model, which can be an analogue to subsurface reservoir studies.

Keywords: LiDAR, outcrop, high resolution, sandstone faceis, connectivity model

Procedia PDF Downloads 205
1864 Development and Acceptance of a Proposed Module for Enhancing the Reading and Writing Skills in Baybayin: The Traditional Writing System in the Philippines

Authors: Maria Venus G. Solares

Abstract:

The ancient Filipinos had their own spelling or alphabet that differed from the modern Roman alphabet brought by the Spaniards. It consists of seventeen letters, three vowels, and fourteen consonants and is called Baybayin. The word Baybayin is a Tagalog word that refers to all the letters used in writing a language, an alphabet; however, it is also a syllable. The House Bill 4395, first proposed by Rep. Leopoldo Bataoil of the second district of Pangasinan in 2011, which later became House Bill 1022 of what he called The Declaration of the Baybayin as the National Writing System of the Philippines, prompted the researcher to conduct a study on the topic. The main objective of this study was to develop and assess the proposed module for enhancing the reading and writing skills in Baybayin of the students. The researchers wanted to ensure the acceptability of the Baybayin using the proposed module and meet the needs of students in developing their ability to read and write Baybayin through the module. The researchers used quasi-experimental research in this study. The data was collected through the initial and final analysis of the students of Adamson University's ABM 1102 using convenient sampling techniques. Based on statistical analysis of data using weighted mean, standard deviation, and paired t-tests, the proposed module helped improve the students' literacy skills, and the response exercises in the proposed module changed the acceptability of the Baybayin in their minds. The study showed that there was an important difference in the scores of students before and after the use of the module. The student's response to the assessment of their reading and writing skills on Baybayin was highly acceptable. This study will help develop the reading and writing skills of the students in Baybayin and teach Baybayin in response to the revival of a part of Philippine culture that has been long forgotten.

Keywords: Baybayin, proposed module, skill, acceptability

Procedia PDF Downloads 108
1863 Household's Willingness to Pay for Safe Non-Timber Forest Products at Morikouali-Ye Community Forest in Cameroon

Authors: Eke Balla Sophie Michelle

Abstract:

Forest provides a wide range of environmental goods and services among which, biodiversity or consumption goods and constitute public goods. Despite the importance of non-timber forest products (NTFPs) in sustaining livelihood and poverty smoothening in rural communities, they are highly depleted and poorly conserved. Yokadouma is a town where NTFPs is a renewable resource in active exploitation. It has been found that such exploitation is done in the same conditions as other localities that have experienced a rapid depletion of their NTFPs in destination to cities across Cameroon, Central Africa, and overseas. Given these realities, it is necessary to access the consequences of this overexploitation through negative effects on both the population and the environment. Therefore, to enhance participatory conservation initiatives, this study determines the household’s willingness to pay in community forest (CF) of Morikouali-ye, eastern region of Cameroon, for sustainable exploitation of NTFPs using contingent valuation method (CVM) through two approaches, one parametric (Logit model) and the other non-parametric (estimator of the Turnbull lower bound). The results indicate that five species are the most collected in the study area: Irvingia gabonensis, the Ricinodendron heudelotii, Gnetum, the Jujube and bark, their sale contributes significantly to 41 % of total household income. The average willingness to pay through the Logit model and the Turnbull estimator is 6845.2861 FCFA and 4940 FCFA respectively per household per year with a social cost of degradation estimated at 3237820.3253 FCFA years. The probability to pay increases with income, gender, number of women in the household, age, the commercial activity of NTFPs and decreases with the concept of sustainable development.

Keywords: non timber forest product, contingent valuation method, willingness to pay, sustainable development

Procedia PDF Downloads 425
1862 Seven Brothers and Sisters of Severely Disabled Children Speak up about Their Everyday Challenges and Needs : A Multiple Case Study

Authors: Myriam Castonguay, Florence Vinit

Abstract:

This study aims to gain a better understanding of the lived experience of seven children growing up in a family where another child is severely disabled, informed by family systems theory and the socio-ecological model of development. In depth semi-structured interviews were conducted with seven children who described they everyday life since their brother’s or sister’s diagnosis. Thematic analysis revealed four themes : struggling with loneliness inside the family, supporting the disabled child through its journey, accommodating to a changing routine and keeping a “bubble” for oneself. Brothers and sisters depict a family life characterized by much loneliness, with severe disabilities requiring ongoing care and prolonged hospitalizations. In the midst of adversity, siblings describe themselves as highly committed to supporting the disabled child and to preserve family cohesion, even if that means getting exposed to emotionally challenging situations and adjusting their daily routine frequently. Children recount that keeping up with schoolwork and leisure activities of their own is central to their well-being. Having a space where one can reconnect with his ordinary life as a kid is also deemed very important. This study reminds us that more needs to be done to counteract the loneliness experienced by siblings through the family experience of disability. Family members and clinicians need to be extra vigilant to ensure siblings’ needs don’t go unnoticed or dismissed, as it may be difficult for this population of children to voice their own experience and needs. Family, school and other actors in the community may help brothers and sisters pursue their personal dreams, goals and projects, to continue experiencing well-being despite adverse life circumstances.

Keywords: sibling’s lived experience of disability, sibling’s needs at various levels of the ecosystem, family adjustment to the disability experience, supporting family wellness through the disability experience

Procedia PDF Downloads 99
1861 Characterization of Biocomposites Based on Mussel Shell Wastes

Authors: Suheyla Kocaman, Gulnare Ahmetli, Alaaddin Cerit, Alize Yucel, Merve Gozukucuk

Abstract:

Shell wastes represent a considerable quantity of byproducts in the shellfish aquaculture. From the viewpoint of ecofriendly and economical disposal, it is highly desirable to convert these residues into high value-added products for industrial applications. So far, the utilization of shell wastes was confined at relatively lower levels, e.g. wastewater decontaminant, soil conditioner, fertilizer constituent, feed additive and liming agent. Shell wastes consist of calcium carbonate and organic matrices, with the former accounting for 95-99% by weight. Being the richest source of biogenic CaCO3, shell wastes are suitable to prepare high purity CaCO3 powders, which have been extensively applied in various industrial products, such as paper, rubber, paints and pharmaceuticals. Furthermore, the shell waste could be further processed to be the filler of polymer composites. This paper presents a study on the potential use of mussel shell waste as biofiller to produce the composite materials with different epoxy matrices, such as bisphenol-A type, CTBN modified and polyurethane modified epoxy resins. Morphology and mechanical properties of shell particles reinforced epoxy composites were evaluated to assess the possibility of using it as a new material. The effects of shell particle content on the mechanical properties of the composites were investigated. It was shown that in all composites, the tensile strength and Young’s modulus values increase with the increase of mussel shell particles content from 10 wt% to 50 wt%, while the elongation at break decreased, compared to pure epoxy resin. The highest Young’s modulus values were determined for bisphenol-A type epoxy composites.

Keywords: biocomposite, epoxy resin, mussel shell, mechanical properties

Procedia PDF Downloads 302
1860 Solar-Blind Ni-Schottky Photodetector Based on MOCVD Grown ZnGa₂O₄

Authors: Taslim Khan, Ray Hua Horng, Rajendra Singh

Abstract:

This study presents a comprehensive analysis of the design, fabrication, and performance evaluation of a solar-blind Schottky photodetector based on ZnGa₂O₄ grown via MOCVD, utilizing Ni/Au as the Schottky electrode. ZnGa₂O₄, with its wide bandgap of 5.2 eV, is well-suited for high-performance solar-blind photodetection applications. The photodetector demonstrates an impressive responsivity of 280 A/W, indicating its exceptional sensitivity within the solar-blind ultraviolet band. One of the device's notable attributes is its high rejection ratio of 10⁵, which effectively filters out unwanted background signals, enhancing its reliability in various environments. The photodetector also boasts a photodetector responsivity contrast ratio (PDCR) of 10⁷, showcasing its ability to detect even minor changes in incident UV light. Additionally, the device features an outstanding detective of 10¹⁸ Jones, underscoring its capability to precisely detect faint UV signals. It exhibits a fast response time of 80 ms and an ON/OFF ratio of 10⁵, making it suitable for real-time UV sensing applications. The noise-equivalent power (NEP) of 10^-17 W/Hz further highlights its efficiency in detecting low-intensity UV signals. The photodetector also achieves a high forward-to-backward current rejection ratio of 10⁶, ensuring high selectivity. Furthermore, the device maintains an extremely low dark current of approximately 0.1 pA. These findings position the ZnGa₂O₄-based Schottky photodetector as a leading candidate for solar-blind UV detection applications. It offers a compelling combination of sensitivity, selectivity, and operational efficiency, making it a highly promising tool for environments requiring precise and reliable UV detection.

Keywords: wideband gap, solar blind photodetector, MOCVD, zinc gallate

Procedia PDF Downloads 17
1859 Policy and System Research for Health of Ageing Population

Authors: Sehrish Ather

Abstract:

Introduction: To improve organizational achievements through the production of new knowledge, health policy and system research is the basic requirement. An aging population is always the source of the increased burden of chronic diseases, disabilities, mental illnesses, and other co-morbidities; therefore the provision of quality health care services to every group of the population should be achieved by making strong policy and system research for the betterment of health care system. Unfortunately, the whole world is lacking policies and system research for providing health care to their elderly population. Materials and Methods: A literature review of published studies on aging diseases was done, ranging from the year 2011-2018. Geriatric, population, health policy, system, and research were the key terms used for the search. Databases searched were Google Scholar, PubMed, Science Direct, Ovid, and Research Gate. Grey literature was searched from various websites, including IHME, Library of the University of Lahore, World Health Organization (Ageing and Life Course), and Personal communication with Neuro-physicians. After careful reviewing published and un-published information, it was decided to carry on with commentary. Results and discussion: Most of the published studies have highlighted the need to advocate the funders of health policy and stakeholders of healthcare system research, and it was detected as a major issue, research on policy and healthcare system to provide health care to 'geriatric population' was found as highly neglected area. Conclusion: It is concluded that physicians are more involved with the policy and system research regarding any type of diseases, but scientists and researchers of basic and social science are less likely to be involved in methods used for health policy and system research due to lack of funding and resources. Therefore ageing diseases should be considered as a priority, and comprehensive policy and system research should be initiated for diseases of the geriatric population.

Keywords: geriatric population, health care system, health policy, system research

Procedia PDF Downloads 92
1858 Moving from Computer Assisted Learning Language to Mobile Assisted Learning Language Edutainment: A Trend for Teaching and Learning

Authors: Ahmad Almohana

Abstract:

Technology has led to rapid changes in the world, and most importantly to education, particularly in the 21st century. Technology has enhanced teachers’ potential and has resulted in the provision of greater interaction and choices for learners. In addition, technology is helping to improve individuals’ learning experiences and building their capacity to read, listen, speak, search, analyse, memorise and encode languages, as well as bringing learners together and creating a sense of greater involvement. This paper has been organised in the following way: the first section provides a review of the literature related to the implementation of CALL (computer assisted learning language), and it explains CALL and its phases, as well as attempting to highlight and analyse Warschauer’s article. The second section is an attempt to describe the move from CALL to mobilised systems of edutainment, which challenge existing forms of teaching and learning. It also addresses the role of the teacher and the curriculum content, and how this is affected by the computerisation of learning that is taking place. Finally, an empirical study has been conducted to collect data from teachers in Saudi Arabia using quantitive and qualitative method tools. Connections are made between the area of study and the personal experience of the researcher carrying out the study with a methodological reflection on the challenges faced by the teachers of this same system. The major findings were that it is worth spelling out here that despite the circumstances in which students and lecturers are currently working, the participants revealed themselves to be highly intelligent and articulate individuals who were constrained from revealing this criticality and creativity by the system of learning and teaching operant in most schools.

Keywords: CALL, computer assisted learning language, EFL, English as a foreign language, ELT, English language teaching, ETL, enhanced technology learning, MALL, mobile assisted learning language

Procedia PDF Downloads 156
1857 Development of New Localized Surface Plasmon Resonance Interfaces Based on ITO Au NPs/ Polymer for Nickel Detection

Authors: F. Z. Tighilt, N. Belhaneche-Bensemra, S. Belhousse, S. Sam, K. Lasmi, N. Gabouze

Abstract:

Recently, the gold nanoparticles (Au NPs) became an active multidisciplinary research topic. First, Au thin films fabricated by alkylthiol-functionalized Au NPs were found to have vapor sensitive conductivities, they were hence widely investigated as electrical chemiresistors for sensing different vapor analytes and even organic molecules in aqueous solutions. Second, Au thin films were demonstrated to have speciallocalized surface plasmon resonances (LSPR), so that highly ordered 2D Au superlattices showed strong collective LSPR bands due to the near-field coupling of adjacent nanoparticles and were employed to detect biomolecular binding. Particularly when alkylthiol ligands were replaced by thiol-terminated polymers, the resulting polymer-modified Au NPs could be readily assembled into 2D nanostructures on solid substrates. Monolayers of polystyrene-coated Au NPs showed typical dipolar near-field interparticle plasmon coupling of LSPR. Such polymer-modified Au nanoparticle films have an advantage that the polymer thickness can be feasibly controlled by changing the polymer molecular weight. In this article, the effect of tin-doped indium oxide (ITO) coatings on the plasmonic properties of ITO interfaces modified with gold nanostructures (Au NSs) is investigated. The interest in developing ITO overlayers is multiple. The presence of a con-ducting ITO overlayer creates a LSPR-active interface, which can serve simultaneously as a working electrode in an electro-chemical setup. The surface of ITO/ Au NPs contains hydroxyl groups that can be used to link functional groups to the interface. Here the covalent linking of nickel /Au NSs/ITO hybrid LSPR platforms will be presented.

Keywords: conducting polymer, metal nanoparticles (NPs), LSPR, poly (3-(pyrrolyl)–carboxylic acid), polypyrrole

Procedia PDF Downloads 257
1856 Entrepreneurial Orientation and Innovation Outcomes in Ghanaian Social Enterprises: Interaction Effect of Organizational Unlearning

Authors: Stephen Oduro

Abstract:

With a quantitative research design, this study seeks to analyze how, an intangible resource, Organisational Unlearning shapes the relationship between Entrepreneurial Orientation (EO) and Innovation Outcomes among social entrepreneurship organizations in Ghana. The Resource-Based View (RBV) of the firm and EO-Performance Contingency framework was adopted as the underpinning theories of the study. Entrepreneurial Orientation dimensions, namely Innovativeness, Autonomy, Risk-Taking, Proactiveness, and Competitive aggressiveness were examined to determine its significant, direct influence on the Innovation Outcomes of the social enterprises in Ghana. Organizational Unlearning dimensions, specifically examination of lens fitting, the consolidation of emergent understandings, and framework for changing individual habits were explored to determine whether they strengthen or weaken the direct nexus between Entrepreneurial Orientation dimensions and Innovation Outcomes. A self-administered questionnaire was administered to 556 targeted social enterprises across Africa through online questionnaire platform and the data generated and proposed hypotheses were analyzed and tested using Structural Equation Model-Partial Least Square (SEM-PLS 3) statistical tool. The findings revealed that EO dimensions, specifically proactiveness, autonomy, innovativeness, and risk-taking are positively related to IO, but we found no significant support for competitive aggressiveness. The findings, moreover, divulged that the positive, direct relationship between EO and IO is highly strengthened by OU. It is concluded that OU fully moderates the direct link between EO and IO. The present study contributes to the our understanding of the interrelationship among Entrepreneurial Orientation, Organizational Unlearning, and Innovation Outcomes in the social entrepreneurship context.

Keywords: entrepreneurial orientation, innovation outcomes, organizational unlearning, RBV, SEM-PLS, social enterprise, Africa

Procedia PDF Downloads 121
1855 Software Development for Both Small Wind Performance Optimization and Structural Compliance Analysis with International Safety Regulations

Authors: K. M. Yoo, M. H. Kang

Abstract:

Conventional commercial wind turbine design software is limited to large wind turbines due to not incorporating with low Reynold’s Number aerodynamic characteristics typically for small wind turbines. To extract maximum annual energy product from an intermediately designed small wind turbine associated with measured wind data, numerous simulation is highly recommended to have a best fitting planform design with proper airfoil configuration. Since depending upon wind distribution with average wind speed, an optimal wind turbine planform design changes accordingly. It is theoretically not difficult, though, it is very inconveniently time-consuming design procedure to finalize conceptual layout of a desired small wind turbine. Thus, to help simulations easier and faster, a GUI software is developed to conveniently iterate and change airfoil types, wind data, and geometric blade data as well. With magnetic generator torque curve, peak power tracking simulation is also available to better match with the magnetic generator. Small wind turbine often lacks starting torque due to blade optimization. Thus this simulation is also embedded along with yaw design. This software provides various blade cross section details at user’s design convenience such as skin thickness control with fiber direction option, spar shape, and their material properties. Since small wind turbine is under international safety regulations with fatigue damage during normal operations and safety load analyses with ultimate excessive loads, load analyses are provided with each category mandated in the safety regulations.

Keywords: GUI software, Low Reynold’s number aerodynamics, peak power tracking, safety regulations, wind turbine performance optimization

Procedia PDF Downloads 287
1854 From Ondoy to Habagat: Comparison of the Community Coping Strategies between Barangay Tumana and Provident Village, Marikina City

Authors: Dinnah Feye H. Andal, Ann Laurice V. Salonga

Abstract:

The paper investigates the flooding event that was experienced by Marikina City residents during the onslaught of Tropical Storm Ondoy on September 26, 2009 and during the heavy downpour caused by the southwest monsoon (Habagat) on August 1-8, 2012. Typhoon Ketsana, locally known as Tropical Storm Ondoy, devastated the whole of Marikina City, displacing a lot of people from their homes and damages properties as well, as flood rose at a very short period of time. Meanwhile, the massive amount of rain water brought by the southwest monsoon lasted for a week that also caused flooding to different parts of Metro Manila including Marikina City. This paper examines how the respondents’ experiences of the flooding caused by Tropical Storm Ondoy informed the coping strategies that the households in Barangay Tumana and Provident Village employed during the flooding brought by the southwest monsoon rains. Specifically, the research compares the coping strategies to flood hazards between residents of Barangay Tumana and Provident Village before, during and after the flooding caused by the southwest monsoon rains. Both study sites have relatively low elevation and are located along rivers and creeks which make them highly susceptible to flood. Interviews with affected residents were undertaken to understand how a household's coping strategies contribute to the development of community coping strategies at the respective neighborhood level. Based from the findings, income levels, local politics, religion and social relations between and among neighbors affect the way household and community coping strategies differ in the two case study sites.

Keywords: community coping strategies, Habagat, Marikina, Ondoy

Procedia PDF Downloads 304
1853 Neural Network based Risk Detection for Dyslexia and Dysgraphia in Sinhala Language Speaking Children

Authors: Budhvin T. Withana, Sulochana Rupasinghe

Abstract:

The educational system faces a significant concern with regards to Dyslexia and Dysgraphia, which are learning disabilities impacting reading and writing abilities. This is particularly challenging for children who speak the Sinhala language due to its complexity and uniqueness. Commonly used methods to detect the risk of Dyslexia and Dysgraphia rely on subjective assessments, leading to limited coverage and time-consuming processes. Consequently, delays in diagnoses and missed opportunities for early intervention can occur. To address this issue, the project developed a hybrid model that incorporates various deep learning techniques to detect the risk of Dyslexia and Dysgraphia. Specifically, Resnet50, VGG16, and YOLOv8 models were integrated to identify handwriting issues. The outputs of these models were then combined with other input data and fed into an MLP model. Hyperparameters of the MLP model were fine-tuned using Grid Search CV, enabling the identification of optimal values for the model. This approach proved to be highly effective in accurately predicting the risk of Dyslexia and Dysgraphia, providing a valuable tool for early detection and intervention. The Resnet50 model exhibited a training accuracy of 0.9804 and a validation accuracy of 0.9653. The VGG16 model achieved a training accuracy of 0.9991 and a validation accuracy of 0.9891. The MLP model demonstrated impressive results with a training accuracy of 0.99918, a testing accuracy of 0.99223, and a loss of 0.01371. These outcomes showcase the high accuracy achieved by the proposed hybrid model in predicting the risk of Dyslexia and Dysgraphia.

Keywords: neural networks, risk detection system, dyslexia, dysgraphia, deep learning, learning disabilities, data science

Procedia PDF Downloads 46
1852 Globalisation and the Resulting Labour Exploitation in Business Operations and Supply Chains

Authors: Akilah A. Jardine

Abstract:

The integration and expansion of the global economy have indeed brought about a number of positive changes such as access to new goods and services and the opportunity for individuals and businesses to migrate, communicate, and work globally. Nevertheless, the interconnectedness of world economies is not without its negative and shameful side effects. The subsequent overabundance of goods and services has resulted in heightened competition among firms and their supply chains, fuelling the exploitation of impoverished and vulnerable individuals who are unable to equally salvage from the benefits of the integrated economy. To maintain their position in a highly competitive arena, the operations of many businesses have adopted unethical and unscrupulous practices to maximise profit, often targeting the most marginalised members of society. Simultaneously, in a consumerist obsessed society preoccupied with the consumption and accumulation of material wealth, the demand for goods and services greatly contributes to the pressure on firms, thus bolstering the exploitation of labour. This paper aims to examine the impact of business operations on the practice of labour exploitation. It explores corrupt business practices that firms adopt and key labour exploitative conditions outlined by the International Labour Organization, particularly, paying workers low wages, forcing individuals to work in abusive and unsafe conditions, and considers the issue regarding individuals’ consent to exploitative environments. Further, it considers the role of consumers in creating the high demand for goods and services, which in turn fosters the exploitation of labour. This paper illustrates that the practice of labour exploitation in the economy is a by-product of both global competitive business operations and heightened consumer consumption.

Keywords: globalisation, labour exploitation, modern slavery, sweatshops, unethical business practices

Procedia PDF Downloads 124
1851 Digital System Design for Strategic Improvement Planning in Education: A Socio-Technical and Iterative Design Approach

Authors: Neeley Current, Fatih Demir, Kenneth Haggerty, Blake Naughton, Isa Jahnke

Abstract:

Educational systems seek reform using data-intensive continuous improvement processes known as strategic improvement plans (SIPs). Schools turn to digital systems to monitor, analyze and report SIPs. One technical challenge of these digital systems focuses on integrating a highly diverse set of data sources. Another challenge is to create a learnable sociotechnical system to help administrators, principals and teachers add, manipulate and interpret data. This study explores to what extent one particular system is usable and useful for strategic planning activities and whether intended users see the benefit of the system achieve the goal of improving workflow related to strategic planning in schools. In a three-phase study, researchers used sociotechnical design methods to understand the current workflow, technology use, and processes of teachers and principals surrounding their strategic improvement planning. Additionally, design review and task analysis usability methods were used to evaluate task completion, usability, and user satisfaction of the system. The resulting socio-technical models illustrate the existing work processes and indicate how and at which places in the workflow the newly developed system could have an impact. The results point to the potential of the system but also indicate that it was initially too complicated for use. However, the diverse users see the potential benefits, especially to overcome the diverse set of data sources, and that the system could fill a gap for schools in planning and conducting strategic improvement plans.

Keywords: continuous improvement process, education reform, strategic improvement planning, sociotechnical design, software development, usability

Procedia PDF Downloads 288
1850 Development of Cost-Effective Protocol for Preparation of Dehydrated Paneer (Indian Cottage Cheese) Using Freeze Drying

Authors: Sadhana Sharma, P. K. Nema, Siddhartha Singha

Abstract:

Paneer or Indian cottage cheese is an acid and heat coagulated milk product, highly perishable because of high moisture (58-60 %). Typically paneer is marble to light creamy white in appearance. A good paneer should have cohesive body with slight sponginess or springiness. The texture must be smooth and velvety with close-knit compactness. It should have pleasing mild acidic, slightly sweet and nutty flavour. Consumers today demand simple to prepare, convenient, healthy and natural foods. Dehydrated paneer finds numerous ways to be used. It can be used in curry preparation similar to paneer-in-curry, a delicacy in Indian cuisine. It may be added to granola/ trail mix yielding a high energy snack. If grounded to a powder, it may be used as a cheesy spice mix or used as popcorn seasoning. Dried paneer powder may be added to pizza dough or to a white sauce to turn it into a paneer sauce. Drying of such food hydrogels by conventional methods is associated with several undesirable characteristics including case hardening, longer drying time, poor rehydration ability and fat loss during drying. The present study focuses on developing cost-effective protocol for freeze-drying of paneer. The dehydrated product would be shelf-stable and can be rehydrated to its original state having flavor and texture comparable to the fresh form. Moreover, the final product after rehydration would be more fresh and softer than its frozen counterparts. The developed product would be shelf-stable at room temperature without any addition of preservatives.

Keywords: color, freeze-drying, paneer, texture

Procedia PDF Downloads 145
1849 An In-Depth Experimental Study of Wax Deposition in Pipelines

Authors: Arias M. L., D’Adamo J., Novosad M. N., Raffo P. A., Burbridge H. P., Artana G.

Abstract:

Shale oils are highly paraffinic and, consequently, can create wax deposits that foul pipelines during transportation. Several factors must be considered when designing pipelines or treatment programs that prevents wax deposition: including chemical species in crude oils, flowrates, pipes diameters and temperature. This paper describes the wax deposition study carried out within the framework of Y-TEC's flow assurance projects, as part of the process to achieve a better understanding on wax deposition issues. Laboratory experiments were performed on a medium size, 1 inch diameter, wax deposition loop of 15 mts long equipped with a solid detector system, online microscope to visualize crystals, temperature and pressure sensors along the loop pipe. A baseline test was performed with diesel with no paraffin or additive content. Tests were undertaken with different temperatures of circulating and cooling fluid at different flow conditions. Then, a solution formed with a paraffin added to the diesel was considered. Tests varying flowrate and cooling rate were again run. Viscosity, density, WAT (Wax Appearance Temperature) with DSC (Differential Scanning Calorimetry), pour point and cold finger measurements were carried out to determine physical properties of the working fluids. The results obtained in the loop were analyzed through momentum balance and heat transfer models. To determine possible paraffin deposition scenarios temperature and pressure loop output signals were studied. They were compared with WAT static laboratory methods. Finally, we scrutinized the effect of adding a chemical inhibitor to the working fluid on the dynamics of the process of wax deposition in the loop.

Keywords: paraffin desposition, flow assurance, chemical inhibitors, flow loop

Procedia PDF Downloads 91
1848 Ground Short Circuit Contributions of a MV Distribution Line Equipped with PWMSC

Authors: Mohamed Zellagui, Heba Ahmed Hassan

Abstract:

This paper proposes a new approach for the calculation of short-circuit parameters in the presence of Pulse Width Modulated based Series Compensator (PWMSC). PWMSC is a newly Flexible Alternating Current Transmission System (FACTS) device that can modulate the impedance of a transmission line through applying a variation to the duty cycle (D) of a train of pulses with fixed frequency. This results in an improvement of the system performance as it provides virtual compensation of distribution line impedance by injecting controllable apparent reactance in series with the distribution line. This controllable reactance can operate in both capacitive and inductive modes and this makes PWMSC highly effective in controlling the power flow and increasing system stability in the system. The purpose of this work is to study the impact of fault resistance (RF) which varies between 0 to 30 Ω on the fault current calculations in case of a ground fault and a fixed fault location. The case study is for a medium voltage (MV) Algerian distribution line which is compensated by PWMSC in the 30 kV Algerian distribution power network. The analysis is based on symmetrical components method which involves the calculations of symmetrical components of currents and voltages, without and with PWMSC in both cases of maximum and minimum duty cycle value for capacitive and inductive modes. The paper presents simulation results which are verified by the theoretical analysis.

Keywords: pulse width modulated series compensator (pwmsc), duty cycle, distribution line, short-circuit calculations, ground fault, symmetrical components method

Procedia PDF Downloads 482
1847 Chemiluminescent Detection of Microorganisms in Food/Drug Product Using Reducing Agents and Gold Nanoplates

Authors: Minh-Phuong Ngoc Bui, Abdennour Abbas

Abstract:

Microbial spoilage of food/drug has been a constant nuisance and an unavoidable problem throughout history that affects food/drug quality and safety in a variety of ways. A simple and rapid test of fungi and bacteria in food/drugs and environmental clinical samples is essential for proper management of contamination. A number of different techniques have been developed for detection and enumeration of foodborne microorganism including plate counting, enzyme-linked immunosorbent assay (ELISA), polymer chain reaction (PCR), nucleic acid sensor, electrical and microscopy methods. However, the significant drawbacks of these techniques are highly demand of operation skills and the time and cost involved. In this report, we introduce a rapid method for detection of bacteria and fungi in food/drug products using a specific interaction between a reducing agent (tris(2-carboxylethyl)phosphine (TCEP)) and the microbial surface proteins. The chemical reaction was transferred to a transduction system using gold nanoplates-enhanced chemiluminescence. We have optimized our nanoplates synthetic conditions, characterized the chemiluminescence parameters and optimized conditions for the microbial assay. The new detection method was applied for rapid detection of bacteria (E.coli sp. and Lactobacillus sp.) and fungi (Mucor sp.), with limit of detection as low as single digit cells per mL within 10 min using a portable luminometer. We expect our simple and rapid detection method to be a powerful alternative to the conventional plate counting and immunoassay methods for rapid screening of microorganisms in food/drug products.

Keywords: microorganism testing, gold nanoplates, chemiluminescence, reducing agents, luminol

Procedia PDF Downloads 281
1846 The Prodomain-Bound Form of Bone Morphogenetic Protein 10 is Biologically Active on Endothelial Cells

Authors: Austin Jiang, Richard M. Salmon, Nicholas W. Morrell, Wei Li

Abstract:

BMP10 is highly expressed in the developing heart and plays essential roles in cardiogenesis. BMP10 deletion in mice results in embryonic lethality due to impaired cardiac development. In adults, BMP10 expression is restricted to the right atrium, though ventricular hypertrophy is accompanied by increased BMP10 expression in a rat hypertension model. However, reports of BMP10 activity in the circulation are inconclusive. In particular it is not known whether in vivo secreted BMP10 is active or whether additional factors are required to achieve its bioactivity. It has been shown that high-affinity binding of the BMP10 prodomain to the mature ligand inhibits BMP10 signaling activity in C2C12 cells, and it was proposed that prodomain-bound BMP10 (pBMP10) complex is latent. In this study, we demonstrated that the BMP10 prodomain did not inhibit BMP10 signaling activity in multiple endothelial cells, and that recombinant human pBMP10 complex, expressed in mammalian cells and purified under native conditions, was fully active. In addition, both BMP10 in human plasma and BMP10 secreted from the mouse right atrium were fully active. Finally, we confirmed that active BMP10 secreted from mouse right atrium was in the prodomain-bound form. Our data suggest that circulating BMP10 in adults is fully active and that the reported vascular quiescence function of BMP10 in vivo is due to the direct activity of pBMP10 and does not require an additional activation step. Moreover, being an active ligand, recombinant pBMP10 may have therapeutic potential as an endothelial-selective BMP ligand, in conditions characterized by loss of BMP9/10 signaling.

Keywords: bone morphogenetic protein 10 (BMP10), endothelial cell, signal transduction, transforming growth factor beta (TGF-B)

Procedia PDF Downloads 264
1845 Oxidosqualene Cyclase: A Novel Inhibitor

Authors: Devadrita Dey Sarkar

Abstract:

Oxidosqualene cyclase is a membrane bound enzyme in which helps in the formation of steroid scaffold in higher organisms. In a highly selective cyclization reaction oxidosqualene cyclase forms LANOSTEROL with seven chiral centres starting from the linear substrate 2,3-oxidosqualene. In humans OSC in cholesterol biosynthesis it represents a target for the discovery of novel anticholesteraemic drugs that could complement the widely used statins. The enzyme oxidosqualene: lanosterol cyclase (OSC) represents a novel target for the treatment of hypercholesterolemia. OSC catalyzes the cyclization of the linear 2,3-monoepoxysqualene to lanosterol, the initial four-ringed sterol intermediate in the cholesterol biosynthetic pathway. OSC also catalyzes the formation of 24(S), 25-epoxycholesterol, a ligand activator of the liver X receptor. Inhibition of OSC reduces cholesterol biosynthesis and selectively enhances 24(S),25-epoxycholesterol synthesis. Through this dual mechanism, OSC inhibition decreases plasma levels of low-density lipoprotein (LDL)-cholesterol and prevents cholesterol deposition within macrophages. The recent crystallization of OSC identifies the mechanism of action for this complex enzyme, setting the stage for the design of OSC inhibitors with improved pharmacological properties for cholesterol lowering and treatment of atherosclerosis. While studying and designing the inhibitor of oxidosqulene cyclase, I worked on the pdb id of 1w6k which was the most worked on pdb id and I used several methods, techniques and softwares to identify and validate the top most molecules which could be acting as an inhibitor for oxidosqualene cyclase. Thus, by partial blockage of this enzyme, both an inhibition of lanosterol and subsequently cholesterol formation as well as a concomitant effect on HMG-CoA reductase can be achieved. Both effects complement each other and lead to an effective control of cholesterol biosynthesis. It is therefore concluded that 2,3-oxidosqualene cyclase plays a crucial role in the regulation of intracellular cholesterol homeostasis. 2,3-Oxidosqualene cyclase inhibitors offer an attractive approach for novel lipid-lowering agents.

Keywords: anticholesteraemic, crystallization, statins, homeostasis

Procedia PDF Downloads 334
1844 Elite Child Athletes Are Our Future: Cardiac Adaptation to Monofin Training in Prepubertal Egyptian Athletes

Authors: Magdy Abouzeid, Nancy Abouzeid, Afaf Salem

Abstract:

Background: The elite child athletes are one who has superior athletic talent. Monofin (a single surface swim fin) swimming already proved to be the most efficient method of swimming for human being. This is a novel descriptive study examining myocardial function indices in prepubertal monofin children. The aim of the present study was to determine the influence of long-term monofin training (LTMT), 36 weeks, 6 times per week, 90 min per unit on Myocardial function adaptation in elite child monofin athletes. Methods: 14 elite monofin children aged 11.95 years (± 1.09 yr) took part for (LTMT). All subjects underwent two-dimension, M-mode, and Doppler echocardiography before and after training to evaluate cardiac dimensions and function; septal and posterior wall thickness. Statistical methods of SPSS, means ± SD and paired t test, % of improvement were used. Findings: There was significant difference (p<0.01) and % improvement for all echocardiography parameter after (LTMT). Inter ventricular septal thickness in diastole and in systole increased by 27.9 % and 42.75 %. Left ventricular end systolic dimension and diastole increased by 16.81 % and 42.7 % respectively. Posterior wall thickness in systole very highly increased by 283.3 % and in diastole increased by 51.78 %. Left ventricular mass in diastole and in systole increased by 44.8 % and 40.1 % respectively. Stroke volume (SV) and resting heart rate (HR) significant changed (sv) 25 %, (HR) 14.7 %. Interpretation: the unique swim fin tool and create propulsion and overcome resistance. Further researches are needed to determine the effects of monofin training on right ventricular in child athletes.

Keywords: prepubertal, monofin training, heart athlete's, elite child athlete, echocardiography

Procedia PDF Downloads 325
1843 Sol-Gel Coated Fabric for Controlled Release of Mosquito Repellent

Authors: Bhaskar M. Murai, Neeraj Banchor, Ishveen Chabbra, Madhusudhan Nadgir, S. Vidhya

Abstract:

Sol-gel technology combined with electronics and biochemistry helps to overcome the problems caused by mosquitoes by developing a portable, low-cost device which enables controlled release of trapped compound inside it. It is a wet-chemical technique which is used primarily for fabrication of silicate gel which is usually allowed to dry as per requirement. The outcome is solid rock hard material which is porous and has lots of applications in different fields. Taking porosity as a key factor, allethrin a naturally occurring synthetic compound with molecular mass 302.40 was entrapped inside the sol-gel matrix as a dopant. Allethrin is commonly used as an insecticide and is a key ingredient in commercially available mosquitoes repellent in Asian and subtropical countries. It has low toxicity for humans and birds, and are used in many household insecticides such as RAID as well as mosquito coils. They are however highly toxic to fish and bees. Insects subject to its exposure become paralyzed (nervous system effect) before dying. They are also used as an ultra-low volume spray for outdoor mosquito control. Therefore, there is a need for controlled release of allethrin in the environment. For controlled release of allethrin from sol-gel matrix, its (allethrin) we utilized temperature based controlled evaporation through porous sol-gel. Different types of fabric like cotton, Terri-cotton, polyester, surgical cap, knee-cap etc are studied and the best with maximum absorption capacity is selected to hold the sol-gel matrix with maximum quantity. For sol-gel coating 2 x 2cm cloth pieces are dipped in sol-gel solution for 10 minutes and by calculating the weight difference we concluded that Terri cotton is best suitable for our project. An electronic circuit with heating plate is developed in to test the controlled release of compound. An oscillatory circuit is used to produce the required heat.

Keywords: sol-gel, allethrin, TEOS, biochemistry

Procedia PDF Downloads 357
1842 Anti-Aging Effects of Retinol and Alpha Hydroxy Acid on Elastin Fibers of Artificially Photo-Aged Human Dermal Fibroblast Cell Lines

Authors: Mohammed Jarrar, Shalini Behl, Nadia Shaheen, Abeer Fatima, Reem Nasab

Abstract:

Skin aging is a slow multifactorial process influenced by both internal as well as external factors. Ultra-violet radiations (UV), diet, smoking and personal habits are the most common environmental factors that affect skin aging. Fat contents and fibrous proteins as collagen and elastin are core internal structural components. The direct influence of UV on elastin integrity and health is crucial on aging of skin by time. The deposition of abnormal elastic material is a major marker in a photo-aged skin. Searching for compounds that may protect against cutaneous photo-damage is highly valued. Retinoids and Alpha Hydroxy Acids protective and or repairing effects of UV have been endorsed by some researchers. For consolidating a better understanding of anti and protective effects of such anti-aging agents, we evaluated the combinatory effects of various dosages of lactic acid and retinol on the dermal fibroblasts elastin levels exposed to UV. The UV exposed cells showed significant reduction in the elastin levels. A combination of drugs with a higher concentration of lactic acid (30-35 mM) and a lower concentration of retinol (10-15mg/mL) showed to work better in enhancing elastin concentration in UV exposed cells. We assume this enhancement could be the result of increased tropo-elastin gene expression stimulated by retinol and lactic acid probably repaired the UV irradiated damage by enhancing the amount and integrity of the elastin fibers.

Keywords: alpha hydroxy acid, elastin, retinol, ultraviolet radiations

Procedia PDF Downloads 327
1841 Integrating Efficient Anammox with Enhanced Biological Phosphorus Removal Process Through Flocs Management for Sustainable Ultra-deep Nutrients Removal from Municipal Wastewater

Authors: Qiongpeng Dan, Xiyao Li, Qiong Zhang, Yongzhen Peng

Abstract:

The nutrients removal from wastewater is of great significance for global wastewater recycling and sustainable reuse. Traditional nitrogen and phosphorus removal processes are very dependent on the input of aeration and carbon sources, which makes it difficult to meet the low-carbon goal of energy saving and emission reduction. This study reported a proof-of-concept demonstration of integrating anammox and enhanced biological phosphorus removal (EBPR) by flocs management in a single-stage hybrid bioreactor (biofilms and flocs) for simultaneous nitrogen and phosphorus removal (SNPR). Excellent removal efficiencies of nitrogen (97.7±1.3%) and phosphorus (97.4±0.7%) were obtained in low C/N ratio (3.0±0.5) municipal wastewater treatment. Interestingly, with the loss of flocs, anammox bacteria (Ca. Brocadia) was highly enriched in biofilms, with relative and absolute abundances reaching up to 12.5% and 8.3×1010 copies/g dry sludge, respectively. The anammox contribution to nitrogen removal also rose from 32.6±9.8% to 53.4±4.2%. Endogenous denitrification by flocs was proven to be the main contributor to both nitrite and nitrate reduction, and flocs loss significantly promoted nitrite flow towards anammox, facilitating AnAOB enrichment. Moreover, controlling the floc's solid retention time at around 8 days could maintain a low poly-phosphorus level of 0.02±0.001 mg P/mg VSS in the flocs, effectively addressing the additional phosphorus removal burden imposed by the enrichment of phosphorus-accumulating organisms in biofilms. This study provides an update on developing a simple and feasible strategy for integrating anammox and EBPR for SNPR in mainstream municipal wastewater.

Keywords: anammox process, enhanced biological phosphorus removal, municipal wastewater, sustainable nutrients removal

Procedia PDF Downloads 30
1840 The Methanotrophic Activity in a Landfill Bio-Cover through a Subzero Winter

Authors: Parvin Berenjkar, Qiuyan Yuan, Richard Sparling, Stan Lozecznik

Abstract:

Landfills highly contribute to anthropological global warming through CH₄ emissions. Landfills are usually capped by a conventional soil cover to control the migration of gases. Methane is consumed by CH₄-oxidizing microorganisms known as methanotrophs that naturally exist in the landfill soil cover. The growth of methanotrophs can be optimized in a bio-cover that typically consists of a gas distribution layer (GDL) to homogenize landfill gas fluxes and an overlying oxidation layer composed of suitable materials that support methanotrophic populations. Materials such as mature yard waste composts can provide an inexpensive and favourable porous support for the growth and activity of methanotrophs. In areas with seasonal cold climates, it is valuable to know if methanotrophs in a bio-cover can survive in winter until the next spring, and how deep they are active in the bio-cover to mitigate CH₄. In this study, a pilot bio-cover was constructed in a closed landfill cell in Winnipeg that has a very cold climate in Canada. The bio-cover has a surface area of 2.5 m x 3.5 m and 1.5 m of depth, filled with 50 cm of gravel as a GDL and 70 cm of biosolids compost amended with yard and leaf waste compost. The observed in situ potential of methanotrophs for CH₄ oxidation was investigated at a specific period of time from December 2016 to April 2017 as well as November 2017 to April 2018, when the transition to surface frost and thawing happens in the bio-cover. Compost samples taken from different depths of the bio-cover were incubated in the laboratory under standardized conditions; an optimal air: methane atmosphere, at 22ºC, but at in situ moisture content. Results showed that the methanotrophs were alive oxidizing methane without a lag, indicating that there was the potential for methanotrophic activity at some depths of the bio-cover.

Keywords: bio-cover, global warming, landfill, methanotrophic activity

Procedia PDF Downloads 108
1839 Tourist’s Perception and Identification of Landscape Elements of Traditional Village

Authors: Mengxin Feng, Feng Xu, Zhiyong Lai

Abstract:

As a typical representative of the countryside, traditional Chinese villages are rich in cultural landscape resources and historical information, but they are still in continuous decline. The problems of people's weak protection awareness and low cultural recognition are still serious, and the protection of cultural heritage is imminent. At the same time, with the rapid development of rural tourism, its cultural value has been explored and paid attention to again. From the perspective of tourists, this study aimed to explore people's perception and identity of cultural landscape resources under the current cultural tourism development background. We selected eleven typical landscape elements of Lingshui Village, a traditional village in Beijing, as research objects and conducted a questionnaire survey with two scales of perception and identity to explore the characteristics of people's perception and identification of landscape elements. We found that there was a strong positive correlation between the perception and identity of each element and that geographical location influenced visitors' overall perception. The perception dimensions scored the highest in location, and the lowest in history and culture, and the identity dimensions scored the highest in meaning and lowest in emotion. We analyzed the impact of visitors' backgrounds on people's perception and identity characteristics and found that age and education were two important factors. The elderly had a higher degree of perceived identity, as the familiarity effect increased their attention. Highly educated tourists had more stringent criteria for perception and identification. The above findings suggest strategies for conserving and optimizing landscape elements in the traditional village to improve the acceptance and recognition of cultural information in traditional villages, which will inject new vitality into the development of traditional villages.

Keywords: traditional village, tourist perception, landscape elements, perception and identity

Procedia PDF Downloads 125
1838 Ultrasound-Assisted Sol – Gel Synthesis of Nano-Boehmite for Biomedical Purposes

Authors: Olga Shapovalova, Vladimir Vinogradov

Abstract:

Among many different sol – gel matrices only alumina can be successfully parenteral injected in the human body. And this is not surprising, because boehmite (aluminium oxyhydroxide) is the metal oxide approved by FDA and EMA for intravenous and intramuscular administrations, and also has been using for a longtime as adjuvant for producing of many modern vaccines. In our earlier study, it has been shown, that denaturation temperature of enzymes entrapped in sol-gel boehmite matrix increases for 30 – 60 °С with preserving of initial activity. It makes such matrices more attractive for long-term storage of non-stable drugs. In current work we present ultrasound-assisted sol-gel synthesis of nano-boehmite. This method provides bio-friendly, very stable, highly homogeneous alumina sol with using only water and aluminium isopropoxide as a precursor. Many parameters of the synthesis were studied in details: time of ultrasound treatment, US frequency, surface area, pore and nanoparticle size, zeta potential and others. Here we investigated the dependence of stability of colloidal sols and textural properties of the final composites as a function of the time of ultrasonic treatment. Chosen ultrasonic treatment time was between 30 and 180 minutes. Surface area, average pore diameter and total pore volume of the final composites were measured by surface and pore size analyzer Nova 1200 Quntachrome. It was shown that the matrices with ultrasonic treatment time equal to 90 minutes have the biggest surface area 431 ± 24 m2/g. On the other had such matrices have a smaller stability in comparison with the samples with ultrasonic treatment time equal to 120 minutes that have the surface area 390 ± 21 m2/g. It was shown that the stable sols could be formed only after 120 minutes of ultrasonic treatment, otherwise the white precipitate of boehmite is formed. We conclude that the optimal ultrasonic treatment time is 120 minutes.

Keywords: boehmite matrix, stabilisation, ultrasound-assisted sol-gel synthesis

Procedia PDF Downloads 248
1837 Photocatalytic Degradation of Organic Polluant Reacting with Tungstates: Role of Microstructure and Size Effect on Oxidation Kinetics

Authors: A. Taoufyq, B. Bakiz, A. Benlhachemi, L. Patout, D. V. Chokouadeua, F. Guinneton, G. Nolibe, A. Lyoussi, J-R. Gavarri

Abstract:

Currently, the photo catalytic reactions occurring under solar illumination have attracted worldwide attentions due to a tremendous set of environmental problems. Taking the sunlight into account, it is indispensable to develop highly effective visible-light-driver photo catalysts. Nano structured materials such as MxM’1-xWO6 system are widely studied due to its interesting piezoelectric, dielectric and catalytic properties. These materials can be used in photo catalysis technique for environmental applications, such as waste water treatments. The aim of this study was to investigate the photo catalytic activity of polycrystalline phases of bismuth tungstate of formula Bi2WO6. Polycrystalline samples were elaborated using a coprecipitation technique followed by a calcination process at different temperatures (300, 400, 600 and 900°C). The obtained polycrystalline phases have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Crystal cell parameters and cell volume depend on elaboration temperature. High-resolution electron microscopy images and image simulations, associated with X-ray diffraction data, allowed confirming the lattices and space groups Pca21. The photo catalytic activity of the as-prepared samples was studied by irradiating aqueous solutions of Rhodamine B, associated with Bi2WO6 additives having variable crystallite sizes. The photo catalytic activity of such bismuth tungstates increased as the crystallite sizes decreased. The high specific area of the photo catalytic particles obtained at 300°C seems to condition the degradation kinetics of RhB.

Keywords: Bismuth tungstate, crystallite sizes, electron microscopy, photocatalytic activity, X-ray diffraction.

Procedia PDF Downloads 434