Search results for: development in rural area
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 23629

Search results for: development in rural area

5989 The Role of the Elastic Foundation Having Nonlinear Stiffness Properties in the Vibration of Structures

Authors: E. Feulefack Songong, A. Zingoni

Abstract:

A vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point. Although vibrations can be linear or nonlinear depending on the basic components of the system, the interest is mostly pointed towards nonlinear vibrations. This is because most structures around us are to some extent nonlinear and also because we need more accurate values in an analysis. The goal of this research is the integration of nonlinearities in the development and validation of structural models and to ameliorate the resistance of structures when subjected to loads. Although there exist many types of nonlinearities, this thesis will mostly focus on the vibration of free and undamped systems incorporating nonlinearity due to stiffness. Nonlinear stiffness has been a concern to many engineers in general and Civil engineers in particular because it is an important factor that can bring a good modification and amelioration to the response of structures when subjected to loads. The analysis of systems will be done analytically and then numerically to validate the analytical results. We will first show the benefit and importance of stiffness nonlinearity when it is implemented in the structure. Secondly, We will show how its integration in the structure can improve not only the structure’s performance but also its response when subjected to loads. The results of this study will be valuable to practicing engineers as well as industry practitioners in developing better designs and tools for their structures and mechanical devices. They will also serve to engineers to design lighter and stronger structures and to give good predictions as for the behavior of structures when subjected to external loads.

Keywords: elastic foundation, nonlinear, plates, stiffness, structures, vibration

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5988 Effect of Information and Communication Intervention on Stable Economic Growth in Ethiopia

Authors: Medhin Haftom Hailu

Abstract:

The advancement of information technology has significantly impacted Ethiopia's economy, driving innovation, productivity, job creation, and global connectivity. This research examined the impact of contemporary information and communication technologies on Ethiopian economic progress. The study examined eight variables, including mobile, internet, and fixed-line penetration rates, and five macroeconomic control variables. The results showed a positive and strong effect of ICT on economic growth in Ethiopia, with 1% increase in mobile, internet, and fixed line services penetration indexes resulting in an 8.03, 10.05, and 30.06% increase in real GDP. The Granger causality test showed that all ICT variables Granger caused economic growth, but economic growth Granger caused mobile penetration rate only. The study suggests that coordinated ICT infrastructure development, increased telecom service accessibility, and increased competition in the telecom market are crucial for Ethiopia's economic growth. Ethiopia is attempting to establish a digital economy through massive investment in ensuring ICT quality and accessibility. Thus, the research could enhance in understanding of the economic impact of ICT expansion for successful ICT policy interventions for future research.

Keywords: economic growth, cointegration and error correction, ICT expansion, granger causality, penetration

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5987 Ridership Study for the Proposed Installation of Automatic Guide-way Transit (AGT) System along Sapphire Street in Balanga City, Bataan

Authors: Nelson Andres, Meeko C. Masangcap, John Denver D. Catapang

Abstract:

Balanga City as, the heart of Bataan, is a growing City and is now at its fast pace of development. The growth of commerce in the city results to an increase in commuters who travel back and forth through the city, leading to congestions. Consequently, queuing of vehicles along national roads and even in the highways of the city have become a regular occurrence. This common scenario of commuters flocking the city, private and public vehicles going bumper to bumper, especially during the rush hours, greatly affect the flow of traffic vehicles and is now a burden not only to the commuters but also to the government who is trying to address this dilemma. Seeing these terrible events, the implementation of an elevated Automated Guide-way transit is seen as a possible solution to help in the decongestion of the affected parts of Balanga City.In response to the problem, the researchers identify if it is feasible to have an elevated guide-way transit in the vicinity of Sapphire Street in Balanga City, Bataan. Specifically, the study aims to determine who will be the riders based on the demographic profile, where the trip can be generated and distributed, the time when volume of people usually peaks and the estimated volume of passengers. Statistical analysis is applied to the data gathered to find out if there is an important relationship between the demographic profile of the respondents and their preference of having an elevated railway transit in the City of Balanga.

Keywords: ridership, AGT, railway, elevated track

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5986 Introducing Standardized Nursing Language in Reporting Nursing Care in Resource-Limited Care Environments: An Exploratory Study

Authors: Naomi Mutea, Jossete Jones

Abstract:

The project aimed at exploring the views and perceptions of nurse leaders and educators regarding use of International Classification for Nursing Practice (ICNP) in an informal approach which involved face to face discussions, after which a decision would be made on whether to proceed and propose introduction of ICNP project in Kenya as a pilot project which would mean all nurses would use a standard approach to reporting and documenting nursing care. In addition the project was to determine the best approaches/methods that can be used to introduce ICNP in the Kenyan nursing education and practice environment using the findings of the pilot project. Further four cardex reports were reviewed to establish if nurses on the bedside used a standardized language in documenting and reporting care processes. The cardex reports showed that nurses do not use ICNP or any other standardized language. The results of the discussions revealed that this would be a challenge due to several challenges experienced in conducting nursing research in resource-limited environments. The following questions were asked during the informal discussions with the educators/leaders: •What is currently being taught in terms of standardized nursing language? •Are you familiar with ICNP? •Do you view it advantageous to have a standardized language? •What is the greatest need at the moment in terms of curriculum development for BSN regarding use of standardized nursing language? •If you had a wish to change something in your curriculum, what would that be?

Keywords: nursing, standardized language, ICNP, resource-limited care environments

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5985 Optimization Financial Technology through E-Money PayTren Application: Reducing Poverty in Indonesia with a System Direct Sales Tiered Sharia

Authors: Erwanda Nuryahya, Aas Nurasyiah, Sri Yayu Ninglasari

Abstract:

Indonesia is the fourth most populous country that still has many troubles in its development. One of the problems which is very important and unresolved is poverty. Limited job opportunity is one unresolved cause of it until today. The purpose of making this scientific paper is to know benefits of E-Money Paytren Application to enhance its partners’ income, owned by company Veritra Sentosa International. The methodology used here is the quantitative and qualitative descriptive method by case study approach. The data used are primary and secondary data. The primary data is obtained from interviews and observation to company Veritra Sentosa International and the distribution of 400 questionnaires to Paytren partner. Secondary data is obtained from the literature study and documentary. The result is that the Paytren with a system direct sales tiered syariah proven able to enhance its partners’ income. Therefore, the Optimization Financial Technology through E-Money Paytren Application should be utilized by Indonesians because it is proven that it is able to increase the income of the partners. Therefore, Paytren Application is very useful for the government, the sharia financial industry, and society in reducing poverty in Indonesia.

Keywords: e-money PayTren application, financial technology, poverty, direct sales tiered Sharia

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5984 Geochemical Study of Natural Bitumen, Condensate and Gas Seeps from Sousse Area, Central Tunisia

Authors: Belhaj Mohamed, M. Saidi, N. Boucherab, N. Ouertani, I. Bouazizi, M. Ben Jrad

Abstract:

Natural hydrocarbon seepage has helped petroleum exploration as a direct indicator of gas and/or oil subsurface accumulations. Surface macro-seeps are generally an indication of a fault in an active Petroleum Seepage System belonging to a Total Petroleum System. This paper describes a case study in which multiple analytical techniques were used to identify and characterize trace petroleum-related hydrocarbons and other volatile organic compounds in groundwater samples collected from Sousse aquifer (Central Tunisia). The analytical techniques used for analyses of water samples included gas chromatography-mass spectrometry (GC-MS), capillary GC with flame-ionization detection, Compund Specific Isotope Analysis, Rock Eval Pyrolysis. The objective of the study was to confirm the presence of gasoline and other petroleum products or other volatile organic pollutants in those samples in order to assess the respective implication of each of the potentially responsible parties to the contamination of the aquifer. In addition, the degree of contamination at different depths in the aquifer was also of interest. The oil and gas seeps have been investigated using biomarker and stable carbon isotope analyses to perform oil-oil and oil-source rock correlations. The seepage gases are characterized by high CH4 content, very low δ13CCH4 values (-71,9 ‰) and high C1/C1–5 ratios (0.95–1.0), light deuterium–hydrogen isotope ratios (-198 ‰) and light δ13CC2 and δ13CCO2 values (-23,8‰ and-23,8‰ respectively) indicating a thermogenic origin with the contribution of the biogenic gas. An organic geochemistry study was carried out on the more ten oil seep samples. This study includes light hydrocarbon and biomarkers analyses (hopanes, steranes, n-alkanes, acyclic isoprenoids, and aromatic steroids) using GC and GC-MS. The studied samples show at least two distinct families, suggesting two different types of crude oil origins: the first oil seeps appears to be highly mature, showing evidence of chemical and/or biological degradation and was derived from a clay-rich source rock deposited in suboxic conditions. It has been sourced mainly by the lower Fahdene (Albian) source rocks. The second oil seeps was derived from a carbonate-rich source rock deposited in anoxic conditions, well correlated with the Bahloul (Cenomanian-Turonian) source rock.

Keywords: biomarkers, oil and gas seeps, organic geochemistry, source rock

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5983 Education For Social Justice: A Comparative Study of University Teachers' Conceptions and Practice

Authors: Digby Warren, Jiri Kropac

Abstract:

This comparative study seeks to develop a deeper understanding of what is meant by “education for social justice” (ESJ) - an aspiration articulated by universities, though often without much definition. The research methodology involved thematic analysis of data from in-depth interviews with academics (voluntary participants) in different disciplines and institutions in the UK, Czech Republic and other EU countries. The interviews explored lecturers’ conceptions of ESJ, their practice of it, and associated challenges and enabling factors. Main findings are that ESJ is construed as provision of equitable and conscientising education opportunities that run across the whole higher education (HE) journey, from widening access to HE to stimulating critical learning and awareness that can empower graduates to transform their lives and societies. Teaching practice featured study of topics related to social justice; collaborative and creative learning activities, and assignments offering choice and connection to students’ realities. Student responses could be mixed, occasionally resistant, but mostly positive in terms of gaining increased confidence and awareness of equality and social responsibility. Influences at the macro, meso and mico level could support or limit scope for ESJ. Overall, the study highlights the strong, values-based commitment of HE teachers to facilitating student learning engagement, wellbeing and development towards building a better world.

Keywords: higher education, social justice, inclusivity, diversity

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5982 The Position of Space weather in Africa-Education and Outreach

Authors: Babagana Abubakar, Alhaji Kuya

Abstract:

Although the field of Space weather science is a young field among the space sciences, but yet history has it that activities related to this science began since the year 1859 when the great solar storm happened which resulted in the disruptions of telegraphs operations around the World at that particular time subsequently making it possible for the scientist Richard Carrington to be able to connect the Solar flare observed a day earlier before the great storm and the great deflection of the Earth’s Magnetic field (geometric storm) simultaneous with the telegraph disruption. However years later as at today with the advent of and the coming into existence of the Explorer 1, the Luna 1 and the establishments of the United States International Space Weather Program, International Geophysical Year (IGY) as well as the International Center for Space Weather Sciences and Education (ICSWSE) have made us understand the Space weather better and enable us well define the field of Space weather science. Despite the successes recorded in the development of Space sciences as a whole over the last century and the coming onboard of specialized bodies/programs on space weather like the International Space Weather Program and the ICSWSE, the majority of Africans including institutions, research organizations and even some governments are still ignorant about the existence of theSpace weather science,because apart from some very few countries like South Africa, Nigeria and Egypt among some few others the majority of the African nations and their academic institutions have no knowledge or idea about the existence of this field of Space science (Space weather).

Keywords: Africa, space, weather, education, science

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5981 Market Access for Foreign Investment in Host States: Municipal Law and International Law

Authors: Qiang Ren

Abstract:

A growing number of states are improving domestic law to better protect and promote foreign investment by changing/upgrading the existing law. However, inconsistency occurs because the new law is different from the ‘old’ law. For example, China has issued an unprecedented Foreign Investment Law and several regulations allowing comprehensive market access for foreign investment in most energy sectors since 2020. However, some laws, rules, regulations, etc. enacted previously remain valid, and the provisions regulating foreign investment do not grant full market access to foreign investment as such. The inconsistency above makes it necessary to investigatehow the international investment treaty law and dispute settlement practice respond to the ‘inconsistency and conflict’ in municipal law andwhat remedy foreign investors can seek under international law if the investment is denied due to inconsistency. Ultimately, it aims to examine how international tribunals should balance the gradually developing legal system of host states and the protection of foreign investors and investments if the host states cannot provide consistency during such a transition period of law development. The research seeks to answer these questions by making a comparative analysis of domestic law on market access to foreign investment, international investment treaties, and dispute arbitral practice. The objective is to examine how international investment treaty law and international investment dispute settlement practice evaluate the conflicts in the municipal law of host states in the admission of foreign investment. It also explores the possibility of harmonisation among them.

Keywords: municipal law, protect and promote foreign investment, international law, host states

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5980 Simscape Library for Large-Signal Physical Network Modeling of Inertial Microelectromechanical Devices

Authors: S. Srinivasan, E. Cretu

Abstract:

The information flow (e.g. block-diagram or signal flow graph) paradigm for the design and simulation of Microelectromechanical (MEMS)-based systems allows to model MEMS devices using causal transfer functions easily, and interface them with electronic subsystems for fast system-level explorations of design alternatives and optimization. Nevertheless, the physical bi-directional coupling between different energy domains is not easily captured in causal signal flow modeling. Moreover, models of fundamental components acting as building blocks (e.g. gap-varying MEMS capacitor structures) depend not only on the component, but also on the specific excitation mode (e.g. voltage or charge-actuation). In contrast, the energy flow modeling paradigm in terms of generalized across-through variables offers an acausal perspective, separating clearly the physical model from the boundary conditions. This promotes reusability and the use of primitive physical models for assembling MEMS devices from primitive structures, based on the interconnection topology in generalized circuits. The physical modeling capabilities of Simscape have been used in the present work in order to develop a MEMS library containing parameterized fundamental building blocks (area and gap-varying MEMS capacitors, nonlinear springs, displacement stoppers, etc.) for the design, simulation and optimization of MEMS inertial sensors. The models capture both the nonlinear electromechanical interactions and geometrical nonlinearities and can be used for both small and large signal analyses, including the numerical computation of pull-in voltages (stability loss). Simscape behavioral modeling language was used for the implementation of reduced-order macro models, that present the advantage of a seamless interface with Simulink blocks, for creating hybrid information/energy flow system models. Test bench simulations of the library models compare favorably with both analytical results and with more in-depth finite element simulations performed in ANSYS. Separate MEMS-electronic integration tests were done on closed-loop MEMS accelerometers, where Simscape was used for modeling the MEMS device and Simulink for the electronic subsystem.

Keywords: across-through variables, electromechanical coupling, energy flow, information flow, Matlab/Simulink, MEMS, nonlinear, pull-in instability, reduced order macro models, Simscape

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5979 Design and Development of 5-DOF Color Sorting Manipulator for Industrial Applications

Authors: Atef A. Ata, Sohair F. Rezeka, Ahmed El-Shenawy, Mohammed Diab

Abstract:

Image processing in today’s world grabs massive attentions as it leads to possibilities of broaden application in many fields of high technology. The real challenge is how to improve existing sorting system applications which consists of two integrated stations of processing and handling with a new image processing feature. Existing color sorting techniques use a set of inductive, capacitive, and optical sensors to differentiate object color. This research presents a mechatronics color sorting system solution with the application of image processing. A 5-DOF robot arm is designed and developed with pick and place operation to be main part of the color sorting system. Image processing procedure senses the circular objects in an image captured in real time by a webcam attached at the end-effector then extracts color and position information out of it. This information is passed as a sequence of sorting commands to the manipulator that has pick-and-place mechanism. Performance analysis proves that this color based object sorting system works very accurate under ideal condition in term of adequate illumination, circular objects shape and color. The circular objects tested for sorting are red, green and blue. For non-ideal condition, such as unspecified color the accuracy reduces to 80%.

Keywords: robotics manipulator, 5-DOF manipulator, image processing, color sorting, pick-and-place

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5978 Changes in Inorganic Element Contents in Potamogeton Natans Exposed to Cement Factory Pollution

Authors: Yavuz Demir, Mucip Genisel, Hulya Turk, Turgay Sisman, Serkan Erdal

Abstract:

In this study, the changes in contents of inorganic elements in the aquatic plant (Potamogeton natans) as a reflection of the impact of chemical nature pollution in a cement factory region (CFR) was evaluated. For this purpose, P, S, K, Ca, Fe, Cl, Mn, Cu, Zn, Mo, Ni, Si, Al, and Cd concentrations were measured in the aquatic plant (Potamogeton natans) taken from a CFR. As a control, aquatic plant was collected at a distance of 2000 m from the outer zone of the cement factory. Inorganic element compositions were measured by energy dispersive X-ray fluorescence spectrometry (EDXRF). Three aquatic plant exhibited similar changes in contents of microelements and macroelements in their leaves. P, S, K, Cl, Ca, and Mo contents in plant grown in the CFR were reduced significantly compared to control plant, whereas their contents of Al, Mn, Fe, Ni, Cu, Zn and Cd were very high. According to these findings, it is possible that aquatic plant (Potamogeton natans) inhabiting in the vicinity of cement factory sustains the deficiency of important essential elements like P, S, K, Ca, and Mo and greatly accumulate heavy metals like Al, Mn, Fe, Ni, Cu, Zn, and Cd. In addition, results of water analysis showed that heavy metal content such as Cu, Pb, Zn, Co, and Al of water taken from CFR was remarkably high than that of outer zone of CFR. These findings with relation to changes in inorganic composition can contribute to be elucidated of effect mechanism on growth and development of aquatic plant (Potamogeton natans) of pollution resulted from cement factories.

Keywords: aquatic plant, cement factory, heavy metal pollution, inorganic element, Potamogeton natans

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5977 Analysis of Attention to the Confucius Institute from Domestic and Foreign Mainstream Media

Authors: Wei Yang, Xiaohui Cui, Weiping Zhu, Liqun Liu

Abstract:

The rapid development of the Confucius Institute is attracting more and more attention from mainstream media around the world. Mainstream media plays a large role in public information dissemination and public opinion. This study presents efforts to analyze the correlation and functional relationship between domestic and foreign mainstream media by analyzing the amount of reports on the Confucius Institute. Three kinds of correlation calculation methods, the Pearson correlation coefficient (PCC), the Spearman correlation coefficient (SCC), and the Kendall rank correlation coefficient (KCC), were applied to analyze the correlations among mainstream media from three regions: mainland of China; Hong Kong and Macao (the two special administration regions of China denoted as SARs); and overseas countries excluding China, such as the United States, England, and Canada. Further, the paper measures the functional relationships among the regions using a regression model. The experimental analyses found high correlations among mainstream media from the different regions. Additionally, we found that there is a linear relationship between the mainstream media of overseas countries and those of the SARs by analyzing the amount of reports on the Confucius Institute based on a data set obtained by crawling the websites of 106 mainstream media during the years 2004 to 2014.

Keywords: mainstream media, Confucius institute, correlation analysis, regression model

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5976 Integrating Experiential Real-World Learning in Undergraduate Degrees: Maximizing Benefits and Overcoming Challenges

Authors: Anne E. Goodenough

Abstract:

One of the most important roles of higher education professionals is to ensure that graduates have excellent employment prospects. This means providing students with the skills necessary to be immediately effective in the workplace. Increasingly, universities are seeking to achieve this by moving from lecture-based and campus-delivered curricula to more varied delivery, which takes students out of their academic comfort zone and allows them to engage with, and be challenged by, real world issues. One popular approach is integration of problem-based learning (PBL) projects into curricula. However, although the potential benefits of PBL are considerable, it can be difficult to devise projects that are meaningful, such that they can be regarded as mere ‘hoop jumping’ exercises. This study examines three-way partnerships between academics, students, and external link organizations. It studied the experiences of all partners involved in different collaborative projects to identify how benefits can be maximized and challenges overcome. Focal collaborations included: (1) development of real-world modules with novel assessment whereby the organization became the ‘client’ for student consultancy work; (2) frameworks where students collected/analyzed data for link organizations in research methods modules; (3) placement-based internships and dissertations; (4) immersive fieldwork projects in novel locations; and (5) students working as partners on staff-led research with link organizations. Focus groups, questionnaires and semi-structured interviews were used to identify opportunities and barriers, while quantitative analysis of students’ grades was used to determine academic effectiveness. Common challenges identified by academics were finding suitable link organizations and devising projects that simultaneously provided education opportunities and tangible benefits. There was no ‘one size fits all’ formula for success, but careful planning and ensuring clarity of roles/responsibilities were vital. Students were very positive about collaboration projects. They identified benefits to confidence, time-keeping and communication, as well as conveying their enthusiasm when their work was of benefit to the wider community. They frequently highlighted employability opportunities that collaborative projects opened up and analysis of grades demonstrated the potential for such projects to increase attainment. Organizations generally recognized the value of project outputs, but often required considerable assistance to put the right scaffolding in place to ensure projects worked. Benefits were maximized by ensuring projects were well-designed, innovative, and challenging. Co-publication of projects in peer-reviewed journals sometimes gave additional benefits for all involved, being especially beneficial for student curriculum vitae. PBL and student projects are by no means new pedagogic approaches: the novelty here came from creating meaningful three-way partnerships between academics, students, and link organizations at all undergraduate levels. Such collaborations can allow students to make a genuine contribution to knowledge, answer real questions, solve actual problems, all while providing tangible benefits to organizations. Because projects are actually needed, students tend to engage with learning at a deep level. This enhances student experience, increases attainment, encourages development of subject-specific and transferable skills, and promotes networking opportunities. Such projects frequently rely upon students and staff working collaboratively, thereby also acting to break down the traditional teacher/learner division that is typically unhelpful in developing students as advanced learners.

Keywords: higher education, employability, link organizations, innovative teaching and learning methods, interactions between enterprise and education, student experience

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5975 Legal Interpretation of the Transplanted Law

Authors: Wahyu Kurniawan

Abstract:

Indonesia developed the legal system radically since 1999. Several laws have been established and mostly the result of transplantation. Laws were made general but legal problems have been growing. In the legal enforcement, the judges have authority to interpret the laws. Authority and freedom are the source of corruption by the courts in Indonesia. Therefore, it should be built the conceptual framework to interpret the transplanted laws as the legal basis in deciding the cases. This article describes legal development based on interpretation of transplanted law in Indonesia by using the Indonesian Supervisory Commission for Business Competition (KPPU) decisions between 2000 and 2010 as the object of the research. The study was using law as a system theory and theories of legal interpretation especially the static and dynamic interpretations. The research showed that the KPPU interpreted the concept that exists in the Competition Law by using static and dynamic interpretation. Static interpretation was used to interpret the legal concepts based on two grounds, minute of meeting during law making process and the definitions that have been recognized in the Indonesian legal system. Dynamic interpretation was used when the KPPU developing the definition of the legal concepts. The general purpose of the law and the theories of the basis of the law were the conceptual framework in using dynamic interpretation. There are two recommendations in this article. Firstly, interpreting the laws by the judges should be based on the correct conceptual framework. Secondly, the technique of interpreting the laws would be the method of controlling the judges.

Keywords: legal interpretation, legal transplant, competition law, KPPU

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5974 Preliminary Study of the Hydrothermal Polymetallic Ore Deposit at the Karancs Mountain, North-East Hungary

Authors: Eszter Kulcsar, Agnes Takacs, Gabriella B. Kiss, Peter Prakfalvi

Abstract:

The Karancs Mountain is part of the Miocene Inner Carpathian Volcanic Belt and is located in N-NE Hungary, along the Hungarian-Slovakian border. The 14 Ma old andesitic-dacitic units are surrounded by Oligocene sedimentary units (sandstone, siltstone). The host rocks of the mineralisation are siliceous and/or argillaceous volcanic units, quartz veins, hydrothermal breccia, and strongly silicified vuggy rocks, found in the various altered volcanic units. The hydrothermal breccia consists of highly silicified vuggy quartz clasts in quartz matrix. The hydrothermal alteration of the host units shows structural control at the deeper levels. The main ore minerals are galena, pyrite, marcasite, sphalerite, hematite, magnetite, arsenopyrite, anglesite and argentite The mineralisation was first mentioned in 1944 and the first exploration took place between 1961 and 1962 in the area. The first ore geological studies were performed between 1984-1985. The exploration programme was limited only to surface sampling; no drilling programme was performed. Petrographical and preliminary fluid inclusion studies were performed on calcite samples from a galena-bearing vein. Despite the early discovery of the mineralisation, no detailed description is available, thus its size, characteristics, and origin have remained unknown. The aim of this study is to examine the mineralisation, describe the characteristics in detail and to test the possible gold content of the various quartz veins and breccias. Finally, we also investigate the potential relation of the hydrothermal mineralisation to the surrounding similar mineralisations with similar ages (e.g. W-Mátra Mountains in Hungary, Banska Bystrica, Banska Stiavnica in Slovakia) in order to place the mineralisation within the volcanic-hydrothermal evolution of the Miocene Inner Carpathian Belt. As first steps, the study includes field mapping, traditional petrological and ore microscopy; X-ray diffraction analysis; SEM-EDS and EMPA studies on ore minerals, to obtain mineral chemical information. Fluid inclusion petrography and microthermometry and micro-Raman-spectroscopy studies are also planned on quartz-hosted inclusions to investigate the physical and chemical properties of the ore-forming fluid.

Keywords: epithermal, Karancs Mountain, Hungary, Miocene Inner Carpathian volcanic belt, polimetallic ore deposit

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5973 Lessons Learned from Push-Plus Implementation in Northern Nigeria

Authors: Aisha Giwa, Mohammed-Faosy Adeniran, Olufunke Femi-Ojo

Abstract:

Four decades ago, the World Health Organization (WHO) launched the Expanded Programme on Immunization (EPI). The EPI blueprint laid out the technical and managerial functions necessary to routinely vaccinate children with a limited number of vaccines, providing protection against diphtheria, tetanus, whooping cough, measles, polio, and tuberculosis, and to prevent maternal and neonatal tetanus by vaccinating women of childbearing age with tetanus toxoid. Despite global efforts, the Routine Immunization (RI) coverage in two of the World Health Organization (WHO) regions; the African Region and the South-East Asia Region, still remains short of its targets. As a result, the WHO Regional Director for Africa declared 2012 as the year for intensifying RI in these regions and this also coincided with the declaration of polio as a programmatic emergency by the WHO Executive Board. In order to intensify routine immunization, the National Routine Immunization Strategic Plan (2013-2015) stated that its core priority is to ensure 100% adequacy and availability of vaccines for safe immunization. To achieve 100% availability, the “PUSH System” and then “Push-Plus” were adopted for vaccine distribution, which replaced the inefficient “PULL” method. The NPHCDA plays the key role in coordinating activities in area advocacy, capacity building, engagement of 3PL for the state as well as monitoring and evaluation of the vaccine delivery process. eHealth Africa (eHA) is a player as a 3PL service provider engaged by State Primary Health Care Boards (SPHCDB) to ensure vaccine availability through Vaccine Direct Delivery (VDD) project which is essential to successful routine immunization services. The VDD project ensures the availability and adequate supply of high-quality vaccines and immunization-related materials to last-mile facilities. eHA’s commitment to the VDD project saw the need for an assessment of the project vis-a-vis the overall project performance, evaluation of a process for necessary improvement suggestions as well as general impact across Kano State (Where eHA had transitioned to the state), Bauchi State (currently manage delivery to all LGAs except 3 LGAs currently being managed by the state), Sokoto State (eHA currently covers all LGAs) and Zamfara State (Currently, in-sourced and managed solely by the state).

Keywords: cold chain logistics, health supply chain system strengthening, logistics management information system, vaccine delivery traceability and accountability

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5972 Connectivity: Connecting ActivityRethinking Streets as Public Space under the Six Dimensions of Urban Space Design in the Context of Bangladesh

Authors: Manal Anis, Bin Bakhti Sayeed

Abstract:

With the encroachment of automobile upon our communities for decades and the concomitant urban sprawl resulting in a loss of public place, it was only a matter of time before people, realizing the role of streets in stimulating urban prosperity, would start reclaiming them to rebuild their communities. In order for this restoration of communities to take effect it is imperative that streets be freed from the dominance of motor vehicles. A holistic approach to pedestrian-friendly street environment can help build communities that embody the cities in which they are found. While the developed countries are finding more and more innovative ways to integrate walkable streets to foster communal living, the developing countries still have a long way to go. Since Dhaka is still struggling to balance the growing needs of accommodating automobiles for increased population with the loss of urban community life that comes with it, it is high time that alternate approaches are looked into. This study aims to understand streets as a living corridor through which one discovers and identifies with the city. The research area is chosen to be Manik Mia Avenue, overlooking the South Plaza of the National Parliament Building in Dhaka city. Being the site of supreme power, it is precisely this symbolic importance that the National Parliament Building has in the psyche of Bangladeshis, which has given Manik Mia Avenue a significant place in the country’s history. Above all, being an avenue it is essentially a neutral territory, universally accessible, inclusive and pluralist. The needs of the Avenue’s frequent users are analyzed with the help of a multi-method approach to survey consisting of an empirical study, a questionnaire survey and interview with relevant users. The research then tries to understand the concept of walkability by exploring the different ways in which the built environment influences walking. For this analysis, the six dimensions of Matthew Carmona are taken as a guideline for a holistic approach toward the different interacting facets of an urban public space. Based on the studies, a set of criteria is proposed to evaluate, plan and design streets that are more contextual in nature. The study concludes with how the existing street patterns of Dhaka city can be rethought and redesigned to cater to peoples’ need for a public place. The proposal is meant to be an inspiration for further studies in this respect in the context of Bangladesh.

Keywords: public space, six dimensions, street, urban, walkability

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5971 Life Cycle Analysis of Using Brick Waste in Road Technology

Authors: Mezhoud Samy, Toumi Youcef, Boukendekdji Otmane

Abstract:

Nowadays, industrial by-products and waste are increasing along with public needs increase. The engineering sector has turned to sustainable development by emphasizing the aspects of environmental and life cycle assessment as an important objective. Among this waste, the remains of the red bricks (DBR) may be an alternative worth checking out, given their availability and abundance at the construction sites. In this context, this work aims to valorize DBR in the concrete road (BR). The incorporation of DBR is carried out by the substitution of the granular fractions of mixtures from noble quarry materials. The experimental plan aims to determine the physico-mechanical performance and environmental performance of manufactured BRs from DBR with a cement content (6.5%) and compared with a control BR without DBR. The studied characteristics are proctor, resistance to compression, resistance to flexural tensile at 7 and 28 days, modulus of elasticity, and total shrinkage. The results of this experimental study showed that the characteristics of recycled aggregates (DBR) are lower than those of natural aggregates but remain acceptable with respect to regulations. Results demonstrate the mechanical performance of BR made from less DBR than the control BR without DBR but remains appreciable and encourage their jobs in the road sector. Recycled aggregates can constitute an interesting economic and ecological alternative but require elementary precautions before any use.

Keywords: life cycle assessment, brick waste, road concrete, performance

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5970 Speeding Up Lenia: A Comparative Study Between Existing Implementations and CUDA C++ with OpenGL Interop

Authors: L. Diogo, A. Legrand, J. Nguyen-Cao, J. Rogeau, S. Bornhofen

Abstract:

Lenia is a system of cellular automata with continuous states, space and time, which surprises not only with the emergence of interesting life-like structures but also with its beauty. This paper reports ongoing research on a GPU implementation of Lenia using CUDA C++ and OpenGL Interoperability. We demonstrate how CUDA as a low-level GPU programming paradigm allows optimizing performance and memory usage of the Lenia algorithm. A comparative analysis through experimental runs with existing implementations shows that the CUDA implementation outperforms the others by one order of magnitude or more. Cellular automata hold significant interest due to their ability to model complex phenomena in systems with simple rules and structures. They allow exploring emergent behavior such as self-organization and adaptation, and find applications in various fields, including computer science, physics, biology, and sociology. Unlike classic cellular automata which rely on discrete cells and values, Lenia generalizes the concept of cellular automata to continuous space, time and states, thus providing additional fluidity and richness in emerging phenomena. In the current literature, there are many implementations of Lenia utilizing various programming languages and visualization libraries. However, each implementation also presents certain drawbacks, which serve as motivation for further research and development. In particular, speed is a critical factor when studying Lenia, for several reasons. Rapid simulation allows researchers to observe the emergence of patterns and behaviors in more configurations, on bigger grids and over longer periods without annoying waiting times. Thereby, they enable the exploration and discovery of new species within the Lenia ecosystem more efficiently. Moreover, faster simulations are beneficial when we include additional time-consuming algorithms such as computer vision or machine learning to evolve and optimize specific Lenia configurations. We developed a Lenia implementation for GPU using the C++ and CUDA programming languages, and CUDA/OpenGL Interoperability for immediate rendering. The goal of our experiment is to benchmark this implementation compared to the existing ones in terms of speed, memory usage, configurability and scalability. In our comparison we focus on the most important Lenia implementations, selected for their prominence, accessibility and widespread use in the scientific community. The implementations include MATLAB, JavaScript, ShaderToy GLSL, Jupyter, Rust and R. The list is not exhaustive but provides a broad view of the principal current approaches and their respective strengths and weaknesses. Our comparison primarily considers computational performance and memory efficiency, as these factors are critical for large-scale simulations, but we also investigate the ease of use and configurability. The experimental runs conducted so far demonstrate that the CUDA C++ implementation outperforms the other implementations by one order of magnitude or more. The benefits of using the GPU become apparent especially with larger grids and convolution kernels. However, our research is still ongoing. We are currently exploring the impact of several software design choices and optimization techniques, such as convolution with Fast Fourier Transforms (FFT), various GPU memory management scenarios, and the trade-off between speed and accuracy using single versus double precision floating point arithmetic. The results will give valuable insights into the practice of parallel programming of the Lenia algorithm, and all conclusions will be thoroughly presented in the conference paper. The final version of our CUDA C++ implementation will be published on github and made freely accessible to the Alife community for further development.

Keywords: artificial life, cellular automaton, GPU optimization, Lenia, comparative analysis.

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5969 Methodology of Preliminary Design and Performance of a Axial-Flow Fan through CFD

Authors: Ramiro Gustavo Ramirez Camacho, Waldir De Oliveira, Eraldo Cruz Dos Santos, Edna Raimunda Da Silva, Tania Marie Arispe Angulo, Carlos Eduardo Alves Da Costa, Tânia Cristina Alves Dos Reis

Abstract:

It presents a preliminary design methodology of an axial fan based on the lift wing theory and the potential vortex hypothesis. The literature considers a study of acoustic and engineering expertise to model a fan with low noise. Axial fans with inadequate intake geometry, often suffer poor condition of the flow at the entrance, varying from velocity profiles spatially asymmetric to swirl floating with respect to time, this produces random forces acting on the blades. This produces broadband gust noise which in most cases triggers the tonal noise. The analysis of the axial flow fan will be conducted for the solution of the Navier-Stokes equations and models of turbulence in steady and transitory (RANS - URANS) 3-D, in order to find an efficient aerodynamic design, with low noise and suitable for industrial installation. Therefore, the process will require the use of computational optimization methods, aerodynamic design methodologies, and numerical methods as CFD- Computational Fluid Dynamics. The objective is the development of the methodology of the construction axial fan, provide of design the geometry of the blade, and evaluate aerodynamic performance

Keywords: Axial fan design, CFD, Preliminary Design, Optimization

Procedia PDF Downloads 392
5968 The Role of Teaching Assistants for Deaf Pupils in a Mainstream Primary School in England

Authors: Hatice Yildirim

Abstract:

This study was an investigation into the role of teaching assistants (TAs) for deaf pupils in an English primary school. This study aimed to provide knowledge about how TAs support deaf pupils in mainstream schools in England. It is accepted that TAs have an important role in the inclusion of students with disabilities in mainstream schools. However, there has been a lack of attention paid to the role of TAs for deaf pupils in the literature. A qualitative case study approach was used to address the research questions. Twelve semi-structured classroom observations and six semi-structured interviews were carried out with four TAs and two teachers in one English mainstream primary school. The data analysis followed a thematic analysis framework. The results indicated that TAs are utilised based on a one-on-one support model and are deployed under the class teachers in the classroom. The classroom activities are carried out in small groups with the TAs and the class teacher’s agreement, as per the school’s policy. Findings show that TAs carried out seven different roles in the education of deaf pupils in an English mainstream primary school. Supporting the academic and social development of deaf pupils is TA`s main role. Also, they record pupils’ progress, communicate with pupils’ parents, take on a pastoral care role, tutor pupils in additional support lessons and raise awareness of deaf pupils’ issues.

Keywords: deaf, mainstream primary school, teaching assistant, teaching assistant`s roles

Procedia PDF Downloads 198
5967 Management and Evaluation of the Importance of Porous Media in Biomedical Engineering as Associated with Magnetic Resonance Imaging Besides Drug Delivery

Authors: Fateme Nokhodchi Bonab

Abstract:

Studies related to magnetic resonance imaging (MRI) and drug delivery are reviewed in this study to demonstrate the role of transport theory in porous media in facilitating advances in biomedical applications. Diffusion processes are believed to be important in many therapeutic modalities such as: B. Delivery of drugs to the brain. We analyse the progress in the development of diffusion equations using the local volume average method and the evaluation of applications related to diffusion equations. Torsion and porosity have significant effects on diffusive transport. In this study, various relevant models of torsion are presented and mathematical modeling of drug release from biodegradable delivery systems is analysed. In this study, a new model of drug release kinetics from porous biodegradable polymeric microspheres under bulk and surface erosion of the polymer matrix is presented. Solute drug diffusion, drug dissolution from the solid phase, and polymer matrix erosion have been found to play a central role in controlling the overall drug release process. This work paves the way for MRI and drug delivery researchers to develop comprehensive models based on porous media theory that use fewer assumptions compared to other approaches.

Keywords: MRI, porous media, drug delivery, biomedical applications

Procedia PDF Downloads 84
5966 Enhancing Photocatalytic Hydrogen Production: Modification of TiO₂ by Coupling with Semiconductor Nanoparticles

Authors: Saud Hamdan Alshammari

Abstract:

Photocatalytic water splitting to produce hydrogen (H₂) has obtained significant attention as an environmentally friendly technology. This process, which produces hydrogen from water and sunlight, represents a renewable energy source. Titanium dioxide (TiO₂) plays a critical role in photocatalytic hydrogen production due to its chemical stability, availability, and low cost. Nevertheless, TiO₂'s wide band gap (3.2 eV) limits its visible light absorption and might affect the effectiveness of the photocatalytic. Coupling TiO₂ with other semiconductors is a strategy that can enhance TiO₂ by narrowing its band gap and improving visible light absorption. This paper studies the modification of TiO₂ by coupling it with another semiconductor such as CdS nanoparticles using a reflux reactor and autoclave reactor that helps form a core-shell structure. Characterization techniques, including TEM and UV-Vis spectroscopy, confirmed successful coating of TiO₂ on CdS core, reduction of the band gap from 3.28 eV to 3.1 eV, and enhanced light absorption in the visible region. These modifications are attributed to the heterojunction structure between TiO₂ and CdS.The essential goal of this study is to improve TiO₂ for use in photocatalytic water splitting to enhance hydrogen production. The core-shell TiO₂@CdS nanoparticles exhibited promising results, due to band gap narrowing and improved light absorption. Future work will involve adding Pt as a co-catalyst, which is known to increase surface reaction activity by enhancing proton adsorption. Evaluation of the TiO₂@CdS@Pt catalyst will include performance assessments and hydrogen productivity tests, considering factors such as effective shapes and material ratios. Moreover, the study could be enhanced by studying further modifications to the catalyst and displaying additional performance evaluations. For instance, doping TiO₂ with metals such as nickel (Ni), iron (Fe), and cobalt (Co) and non-metals such as nitrogen (N), carbon (C), and sulfur (S) could positively influence the catalyst by reducing the band gap, enhancing the separation of photogenerated electron-hole pairs, and increasing the surface area, respectively. Additionally, to further improve catalytic performance, examining different catalyst morphologies, such as nanorods, nanowires, and nanosheets, in hydrogen production could be highly beneficial. Optimizing photoreactor design for efficient photon delivery and illumination will further enhance the photocatalytic process. These strategies collectively aim to overcome current challenges and improve the efficiency of hydrogen production via photocatalysis.

Keywords: hydrogen production, photocatalytic, water spliiting, semiconductor, nanoparticles

Procedia PDF Downloads 14
5965 Traditional Drawing, BIM and Erudite Design Process

Authors: Maryam Kalkatechi

Abstract:

Nowadays, parametric design, scientific analysis, and digital fabrication are dominant. Many architectural practices are increasingly seeking to incorporate advanced digital software and fabrication in their projects. Proposing an erudite design process that combines digital and practical aspects in a strong frame within the method was resulted from the dissertation research. The digital aspects are the progressive advancements in algorithm design and simulation software. These aspects have assisted the firms to develop more holistic concepts at the early stage and maintain collaboration among disciplines during the design process. The erudite design process enhances the current design processes by encouraging the designer to implement the construction and architecture knowledge within the algorithm to make successful design processes. The erudite design process also involves the ongoing improvements of applying the new method of 3D printing in construction. This is achieved through the ‘data-sketches’. The term ‘data-sketch’ was developed by the author in the dissertation that was recently completed. It accommodates the decisions of the architect on the algorithm. This paper introduces the erudite design process and its components. It will summarize the application of this process in development of the ‘3D printed construction unit’. This paper contributes to overlaying the academic and practice with advanced technology by presenting a design process that transfers the dominance of tool to the learned architect and encourages innovation in design processes.

Keywords: erudite, data-sketch, algorithm design in architecture, design process

Procedia PDF Downloads 270
5964 Analysis of Influence of Geometrical Set of Nozzles on Aerodynamic Drag Level of a Hero’s Based Steam Turbine

Authors: Mateusz Paszko, Miroslaw Wendeker, Adam Majczak

Abstract:

High temperature waste energy offers a number of management options. The most common energy recuperation systems, that are actually used to utilize energy from the high temperature sources are steam turbines working in a high pressure and temperature closed cycles. Due to the high costs of production of energy recuperation systems, especially rotary turbine discs equipped with blades, currently used solutions are limited in use with waste energy sources of temperature below 100 °C. This study presents the results of simulating the flow of the water vapor in various configurations of flow ducts in a reaction steam turbine based on Hero’s steam turbine. The simulation was performed using a numerical model and the ANSYS Fluent software. Simulation computations were conducted with use of the water vapor as an internal agent powering the turbine, which is fully safe for an environment in case of a device failure. The conclusions resulting from the conducted numerical computations should allow for optimization of the flow ducts geometries, in order to achieve the greatest possible efficiency of the turbine. It is expected that the obtained results should be useful for further works related to the development of the final version of a low drag steam turbine dedicated for low cost energy recuperation systems.

Keywords: energy recuperation, CFD analysis, waste energy, steam turbine

Procedia PDF Downloads 204
5963 Formulation and Technology of the Composition of Essential Oils as a Feed Additive in Poultry with Antibacterial Action

Authors: S. Barbaqadze, M. Goderdzishvili, E. Mosidze, L. Lomtadze, V. Mshvildadze, L. Bakuridze, D. Berashvili, A. Bakuridze

Abstract:

This paper focuses on the formulation of phytobiotic designated for further implantation in poultry farming. Composition was meant to be water-soluble powder containing antibacterial essential oils. The development process involved Thyme, Monarda and Clary sage essential oils. The antimicrobial activity of essential oils composite was meant to be tested against gram-negative and gram-positive bacterial strains. The results are processed using the statistical program Sigma STAT. To make essential oils composition water soluble surfactants were added to them. At the first stage of the study, nine options for the optimal composition of essential oils and surfactants were developed. The effect of the amount of surfactants on the essential oils composition solubility in water has been investigated. On the basis of biopharmaceutical studies, the formulation of phytobiotic has been determined: Thyme, monarda and clary sage essential oils 2:1:1 - 100 parts; Licorice extract 5.25 parts and inhalation lactose 300 parts. A technology for the preparation of phytobiotic has been developed and a technological scheme for the preparation of phytobiotic has been made up. The research was performed within the framework of the grant project CARYS-19-363 funded be the Shota Rustaveli National Science Foundation of Georgia.

Keywords: clary, essential oils, monarda, phytobiotics, poultry, thyme

Procedia PDF Downloads 156
5962 An Attempt to Get Communication Design Students to Reflect: A Content Analysis of Students’ Learning Journals

Authors: C. K. Peter Chuah

Abstract:

Essentially, the intention of reflective journal is meant for students to develop higher-order thinking skills and to provide a 'space' to make their learning experience and thinking, making and feeling visible, i.e., it provides students an opportunity to evaluate their learning critically by focusing on the rationale behind their thinking, making and feeling. In addition, reflective journal also gets the students to focus on how could things be done differently—the possibility, alternative point of views, and opportunities for change. It is hoped that by getting communication design students to reflect at various intervals, they could move away from mere working on the design project and pay more attention to what they thought they have learned in relation to the development of their design ability. Unfortunately, a closer examination—through content analysis—of the learning journals submitted by a group of design students revealed that most of the reflections were descriptive and tended to be a summary of what occurred in the learning experience. While many students were able to describe what they did, very few were able to explain how they were able to do something critically. It can be concluded that to get design students to reflect is a fairly easy task, but to get them to reflect critically could be very challenging. To ensure that design students could benefit from the use of reflective journal as a tool to develop their critical thinking skills, a more systematic and structured approach to the introduction of critical thinking and reflective journal should be built into the design curriculum to provide as much practice and sufficient feedback as other studio subjects.

Keywords: communication design education, critical thinking, reflection, reflective journal

Procedia PDF Downloads 280
5961 Characterization of Polymorphic Forms of Rifaximin

Authors: Ana Carolina Kogawa, Selma Gutierrez Antonio, Hérida Regina Nunes Salgado

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Rifaximin is an oral antimicrobial, gut - selective and not systemic with adverse effects compared to placebo. It is used for the treatment of hepatic encephalopathy, travelers diarrhea, irritable bowel syndrome, Clostridium difficile, ulcerative colitis and acute diarrhea. The crystalline form present in the rifaximin with minimal systemic absorption is α, being the amorphous form significantly different. Regulators are increasingly attention to polymorphisms. Polymorphs can change the form by altering the drug characteristics compromising the effectiveness and safety of the finished product. International Conference on Harmonization issued the ICH Guidance Q6A, which aim to improve the control of polymorphism in new and existing pharmaceuticals. The objective of this study was to obtain polymorphic forms of rifaximin employing recrystallization processes and characterize them by thermal analysis (thermogravimetry - TG and differential scanning calorimetry - DSC), X-ray diffraction, scanning electron microscopy and solubility test. Six polymorphic forms of rifaximin, designated I to VI were obtained by the crystallization process by evaporation of the solvent. The profiles of the TG curves obtained from polymorphic forms of rifaximin are similar to rifaximin and each other, however, the DTG are different, indicating different thermal behaviors. Melting temperature values of all the polymorphic forms were greater to that shown by the rifaximin, indicating the higher thermal stability of the obtained forms. The comparison of the diffractograms of the polymorphic forms of rifaximin with rifaximin α, β and γ constant in patent indicate that forms III, V and VI are formed by mixing polymorph β and α and form III is formed by polymorph β. The polymorphic form I is formed by polymorph β, but with a significant amount of amorphous material. Already, the polymorphic form II consists of polymorph γ, amorphous. In scanning electron microscope is possible to observe the heterogeneity of morphological characteristics of crystals of polymorphic forms among themselves and with rifaximin. The solubility of forms I and II was greater than the solubility of rifaximin, already, forms III, IV and V presented lower solubility than of rifaximin. Similarly, the bioavailability of the amorphous form of rifaximin is considered significantly higher than the form α, the polymorphic forms obtained in this work can not guarantee the excellent tolerability of the reference medicine. Therefore, studies like these are extremely important and they point to the need for greater requirements by the regulatory agencies competent about polymorphs analysis of the raw materials used in the manufacture of medicines marketed globally. These analyzes are not required in the majority of official compendia. Partnerships between industries, research centers and universities would be a viable way to consolidate researches in this area and contribute to improving the quality of solid drugs.

Keywords: electronic microscopy, polymorphism, rifaximin, solubility, X-ray diffraction

Procedia PDF Downloads 656
5960 Tuning the Emission Colour of Phenothiazine by Introduction of Withdrawing Electron Groups

Authors: Andrei Bejan, Luminita Marin, Dalila Belei

Abstract:

Phenothiazine with electron-rich nitrogen and sulfur heteroatoms has a high electron-donating ability which promotes a good conjugation and therefore low band-gap with consequences upon charge carrier mobility improving and shifting of light emission in visible domain. Moreover, its non-planar butterfly conformation inhibits molecular aggregation and thus preserves quite well the fluorescence quantum yield in solid state compared to solution. Therefore phenothiazine and its derivatives are promising hole transport materials for use in organic electronic and optoelectronic devices as light emitting diodes, photovoltaic cells, integrated circuit sensors or driving circuits for large area display devices. The objective of this paper was to obtain a series of new phenothiazine derivatives by introduction of different electron withdrawing substituents as formyl, carboxyl and cyanoacryl units in order to create a push pull system which has potential to improve the electronic and optical properties. Bromine atom was used as electrono-donor moiety to extend furthermore the existing conjugation. The understudy compounds were structural characterized by FTIR and 1H-NMR spectroscopy and single crystal X-ray diffraction. Besides, the single crystal X-ray diffraction brought information regarding the supramolecular architecture of the compounds. Photophysical properties were monitored by UV-vis and photoluminescence spectroscopy, while the electrochemical behavior was established by cyclic voltammetry. The absorption maxima of the studied compounds vary in a large range (322-455 nm), reflecting the different electronic delocalization degree, depending by the substituent nature. In a similar manner, the emission spectra reveal different color of emitted light, a red shift being evident for the groups with higher electron withdrawing ability. The emitted light is pure and saturated for the compounds containing strong withdrawing formyl or cyanoacryl units and reach the highest quantum yield of 71% for the compound containing bromine and cyanoacrilic units. Electrochemical study show reversible oxidative and reduction processes for all the compounds and a close correlation of the HOMO-LUMO band gap with substituent nature. All these findings suggest the obtained compounds as promising materials for optoelectronic devices.

Keywords: electrochemical properties, phenothiazine derivatives, photoluminescence, quantum yield

Procedia PDF Downloads 328