Search results for: world café method
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 25224

Search results for: world café method

8664 Consumer Behavior and Marketing Mixed Factor Effect on Consumer Decision Making for Independent Movies Presented in Lido Cinema

Authors: Pongsawee Supanonth

Abstract:

This study aims to investigate the consumer behavior and marketing mixed factor affect on consumer decision making for independent movies presented in Lido cinema. The research method will use quantitative research, data was collected by questionnaires distributed to the audience in the Lido cinema for 400 sample by accidental sampling technique. Data was analyzed by descriptive statistic including percentage, mean, standard deviation and inferential statistic including independent t-test for hypothesis testing. The results showed that marketing mixed factors affecting consumer decision-making for Independent movies presented in Lido cinema by gender as different as less than the 0.05 significance level, it was found that the kind of movie ,quality of theater ,price of ticket, facility of watching movies, staff services and promotion of Lido cinema respectively had a vital influence on their attention and response which makes the advertisement more attractive is in harmony with the research hypotheses also.

Keywords: consumer behavior, marketing mixed factor, resonance, consumer decision making, Lido cinema

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8663 Hearing Aids Maintenance Training for Hearing-Impaired Preschool Children with the Help of Motion Graphic Tools

Authors: M. Mokhtarzadeh, M. Taheri Qomi, M. Nikafrooz, A. Atashafrooz

Abstract:

The purpose of the present study was to investigate the effectiveness of using motion graphics as a learning medium on training hearing aids maintenance skills to hearing-impaired children. The statistical population of this study consisted of all children with hearing loss in Ahvaz city, at age 4 to 7 years old. As the sample, 60, whom were selected by multistage random sampling, were randomly assigned to two groups; experimental (30 children) and control (30 children) groups. The research method was experimental and the design was pretest-posttest with the control group. The intervention consisted of a 2-minute motion graphics clip to train hearing aids maintenance skills. Data were collected using a 9-question researcher-made questionnaire. The data were analyzed by using one-way analysis of covariance. Results showed that the training of hearing aids maintenance skills with motion graphics was significantly effective for those children. The results of this study can be used by educators, teachers, professionals, and parents to train children with disabilities or normal students.

Keywords: hearing aids, hearing aids maintenance skill, hearing impaired children, motion graphics

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8662 Immigrant Women's Voices and Integrating Feminism into Migration Theory

Authors: Florence Nyemba, Rufaro Chitiyo

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This work features the voices of women as they describe their experiences living in the diaspora either with their families or alone. The contributing authors of this work pursued this project to understand how the women’s personal lives (and those of their families back home) changed (both positively and negatively). The work addressed the following important questions, what is female migration? What are the factors causing women to migrate? What types of migration do women engage in? What is the influence of family relationships on migration? What are the challenges of migration? How do migrant women maintain ties with their home countries? What is the role of social networks in migration? How can feminist theories and methodologies be incorporated in migration studies? Women continue to contribute significantly to mass movements of people across the yet, their voices silent in the literature on migration. History shows that women have always been on the move trying to make a living just like their male counterparts. Whether they migrate as spouses, daughters, or alone, women make up a sizeable portion of migration statistics around the world. These women are migrating independently without the accompaniment of male relatives. This calls for the need to expand research on women as independent migrants without generalizing their experiences as in the case with early studies on international migration. The goal of this work is to offer a rich and detailed description of the lives of immigrant women across the globe using theoretical frameworks that advance gender and migration research. Methodology: This work invited scholars and researchers from across the globe whose research interests were in gender and migration. The work incorporated a variety of methodologies for data collection and analysis, which included oral narratives, interviews, systematic literature reviews and interviews. Conclusion: There is a considerable amount of interest in various topics on gender, violence, and equality throughout social science disciplines in higher education. Therefore, the three major topics covered in this work, Women’s Immigration: Theories and Methodologies, Women as Migrant Workers, and Women as Refugees, Asylees, and Permanent Migrants, can be of interest across social sciences disciplines. Feminist theories can expand the curriculum on identity and gendered roles and norms in societies. Findings of this work advance knowledge of population movements across the globe. This work will also appeal to students and scholars wanting to expand their knowledge on women and migration, migration theories, gender violence, and women empowerment. The topics and issues presented in this work will also assist the international community and lawyers concerned with global migration.

Keywords: gender, feminism, identity formation, international migration

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8661 The Feasibility of Ratification of the United Nation Convention on Contracts for International Sale of Goods by Islamic Countries, Saudi Arabia as a Case

Authors: Ibrahim M. Alwehaibi

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Recently the windows of globalization weirdly open, which increase the trade between the Western countries and Muslim nations. Sales of goods contracts are one of the most common business transaction in the world. This commercial exchange has faced many obstacles. One of the most concerned obstacles is the conflicts between laws. Thus, United Nation created a Convention on Contracts for the International Sale of Goods (CISG). Some of Islamic countries have ratified the CISG, while other Islamic countries have concerns about the feasibility of ratification of the CISG, and many businessmen have a concern of application of the convention. The concerns related to the conflict between CISG and Sharia, and the long debate about the success, ambiguity, and stability of the CISG. Therefore, this research will examine the feasibility of Muslim countries and Muslim businessmen to adopt the CISG by following steps: First, this research will introduce sharia Law (Islamic contracts law) and CISG and provide backgrounds of both laws. Second, this research will compare the provisions of CISG and Sharia and figuring out the conflicts and provide possible solutions for the conflicts. Third, this study will examine the advantages and disadvantages of adopting the CISG and examining the success of the CISG. Fourth, this study will explore the current situation in Islamic countries by taking Saudi Arabia as a case and explore how the application of Sharia law works and the possibility to enforce the CISG and explore the current practice of foreign Sales in Saudi Arabia. The research finds that there are some conflicts between CISG and Sharia Law. The most notable conflicts are interest and uncertainty in considerations. Also, this research finds that it seems that ratification of CISG is not beneficial for Muslim countries because the convention has not reached its goal which is uniformity of laws. Moreover, the CISG has been excluded and ignored by businessmen and some courts. Additionally, this research finds that it could be possible to enforce CISG in Saudi Arabia, provided that no conflict between the enforced provision and Sharia Law. This study is following the competitive and analysis methodologies to reach its findings. The researcher analyzes the provision of CISG and compares them with Sharia rules and finds the conflicts and compatibilities. In fact, CISG has 101 articles, so a comprehensive comparison of all articles in CISG with Sharia is difficult. Thus, in order to deeply analyze all aspects of this issue, this study will exclude some areas of contract which have been discussed by other researchers such as deliver of goods, conformity, and mirror image rules. The comparative section of this study will focus on the most concerned articles that conflict or doubtful of conflict with Sharia, which are interest, uncertainty, statute of limitation, specific performance, and pass of risk.

Keywords: Sharia, CISG, Contracts for International Sale of Goods, contracts, sale of goods, Saudi Arabia

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8660 Resource Constrained Time-Cost Trade-Off Analysis in Construction Project Planning and Control

Authors: Sangwon Han, Chengquan Jin

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Time-cost trade-off (TCTO) is one of the most significant part of construction project management. Despite the significance, current TCTO analysis, based on the Critical Path Method, does not consider resource constraint, and accordingly sometimes generates an impractical and/or infeasible schedule planning in terms of resource availability. Therefore, resource constraint needs to be considered when doing TCTO analysis. In this research, genetic algorithms (GA) based optimization model is created in order to find the optimal schedule. This model is utilized to compare four distinct scenarios (i.e., 1) initial CPM, 2) TCTO without considering resource constraint, 3) resource allocation after TCTO, and 4) TCTO with considering resource constraint) in terms of duration, cost, and resource utilization. The comparison results identify that ‘TCTO with considering resource constraint’ generates the optimal schedule with the respect of duration, cost, and resource. This verifies the need for consideration of resource constraint when doing TCTO analysis. It is expected that the proposed model will produce more feasible and optimal schedule.

Keywords: time-cost trade-off, genetic algorithms, critical path, resource availability

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8659 Performance Estimation of Small Scale Wind Turbine Rotor for Very Low Wind Regime Condition

Authors: Vilas Warudkar, Dinkar Janghel, Siraj Ahmed

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Rapid development experienced by India requires huge amount of energy. Actual supply capacity additions have been consistently lower than the targets set by the government. According to World Bank 40% of residences are without electricity. In 12th five year plan 30 GW grid interactive renewable capacity is planned in which 17 GW is Wind, 10 GW is from solar and 2.1 GW from small hydro project, and rest is compensated by bio gas. Renewable energy (RE) and energy efficiency (EE) meet not only the environmental and energy security objectives, but also can play a crucial role in reducing chronic power shortages. In remote areas or areas with a weak grid, wind energy can be used for charging batteries or can be combined with a diesel engine to save fuel whenever wind is available. India according to IEC 61400-1 belongs to class IV Wind Condition; it is not possible to set up wind turbine in large scale at every place. So, the best choice is to go for small scale wind turbine at lower height which will have good annual energy production (AEP). Based on the wind characteristic available at MANIT Bhopal, rotor for small scale wind turbine is designed. Various Aero foil data is reviewed for selection of airfoil in the Blade Profile. Airfoil suited of Low wind conditions i.e. at low Reynold’s number is selected based on Coefficient of Lift, Drag and angle of attack. For designing of the rotor blade, standard Blade Element Momentum (BEM) Theory is implanted. Performance of the Blade is estimated using BEM theory in which axial induction factor and angular induction factor is optimized using iterative technique. Rotor performance is estimated for particular designed blade specifically for low wind Conditions. Power production of rotor is determined at different wind speeds for particular pitch angle of the blade. At pitch 15o and velocity 5 m/sec gives good cut in speed of 2 m/sec and power produced is around 350 Watts. Tip speed of the Blade is considered as 6.5 for which Coefficient of Performance of the rotor is calculated 0.35, which is good acceptable value for Small scale Wind turbine. Simple Load Model (SLM, IEC 61400-2) is also discussed to improve the structural strength of the rotor. In SLM, Edge wise Moment and Flap Wise moment is considered which cause bending stress at the root of the blade. Various Load case mentioned in the IEC 61400-2 is calculated and checked for the partial safety factor of the wind turbine blade.

Keywords: annual energy production, Blade Element Momentum Theory, low wind Conditions, selection of airfoil

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8658 An Investigation on the Suitability of Dual Ion Beam Sputtered GMZO Thin Films: For All Sputtered Buffer-Less Solar Cells

Authors: Vivek Garg, Brajendra S. Sengar, Gaurav Siddharth, Nisheka Anadkat, Amitesh Kumar, Shailendra Kumar, Shaibal Mukherjee

Abstract:

CuInGaSe (CIGSe) is the dominant thin film solar cell technology. The band alignment of Buffer/CIGSe interface is one of the most crucial parameters for solar cell performance. In this article, the valence band offset (VBOff) and conduction band offset (CBOff) values of Cu(In0.70Ga0.30)Se/ 1 at.% Ga: Mg0.25Zn0.75O (GMZO) heterojunction, grown by dual ion beam sputtering system (DIBS), are calculated to understand the carrier transport mechanism at the heterojunction for the realization of all sputtered buffer-less solar cells. To determine the valence band offset (VBOff), ∆E_V at GMZO/CIGSe heterojunction interface, the standard method based on core-level photoemission is utilized. The value of ∆E_V can be evaluated by considering common core-level peaks. In our study, the values of (Valence band onset)VBOn, obtained by linear extrapolation method for GMZO and CIGSe films are calculated to be 2.86 and 0.76 eV. In the UPS spectra peak positions of Se 3d is observed in UPS spectra at 54.82 and 54.7 eV for CIGSe film and GMZO/CIGSe interface respectively, while the peak position of Mg 2p is observed at 50.09 and 50.12 eV for GMZO and GMZO/CIGSe interface respectively. The optical band gap of CIGSe and GMZO are obtained from absorption spectra procured from spectroscopic ellipsometry are 1.26 and 3.84 eV respectively. The calculated average values of ∆E_v and ∆E_C are estimated to be 2.37 and 0.21 eV, respectively, at room temperature. The calculated positive conduction band offset termed as a spike at the absorber junction is the required criterion for the high-efficiency solar cells for the efficient charge extraction from the junction. So we can conclude that the above study confirms GMZO thin films grown by the dual ion beam sputtering system are the suitable candidate for the CIGSe thin films based ultra-thin buffer-less solar cells. We investigated the band-offset properties at the GMZO/CIGSe heterojunction to verify the suitability of the GMZO for the realization of the buffer-less solar cells. The calculated average values of ∆E_V and ∆E_C are estimated to be 2.37 and 0.21 eV, respectively, at room temperature. The calculated positive conduction band offset termed as a spike at the absorber junction is the required criterion for the high-efficiency solar cells for the efficient charge extraction from the junction. So we can conclude that the above study confirms GMZO thin films grown by the dual ion beam sputtering system are the suitable candidate for the CIGSe thin films based ultra-thin buffer-less solar cells. Acknowledgment: We are thankful to DIBS, EDX, and XRD facility equipped at Sophisticated Instrument Centre (SIC) at IIT Indore. The authors B.S.S and A.K acknowledge CSIR and V.G acknowledge UGC, India for their fellowships. B.S.S is thankful to DST and IUSSTF for BASE Internship Award. Prof. Shaibal Mukherjee is thankful to DST and IUSSTF for BASE Fellowship and MEITY YFRF award. This work is partially supported by DAE BRNS, DST CERI, and DST-RFBR Project under India-Russia Programme of Cooperation in Science and Technology. We are thankful to Mukul Gupta for SIMS facility equipped at UGC-DAE Indore.

Keywords: CIGSe, DIBS, GMZO, solar cells, UPS

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8657 Disposable Coffee Cups Recycling

Authors: Sasan Mohammadi

Abstract:

Due to our passion for coffee, we use 16 billion throwaway coffee cups yearly. Coffee lovers throughout the globe have discovered the hard way that their paper cups are not recyclable, despite what coffee businesses have repeatedly assured them [1] A disposable, single-use coffee cup comprises a paper and polyethylene layer. Polyethylene is a typical material used to fill a coffee cup's inside to keep its structure and provide water and heat resistance. In addition, the polyethylene layer prevents recycling since it is difficult to separate the plastic liner from the paper layer [2]. In addition, owing to the plastic membrane lining many of these cups, they cannot be recycled and may take up to 30 years to biodegrade [3]. Most of researcher try to separate plastic part ,but it is not economical and easy.For this purposes,it is not yet happen. In our research we don't separate plastic, just we make a homogeneous pulp with cold water.then fix it in mold and dry it,after completely drying cycle we heated the product in 100 degree of centigrade this cause a sintering effect by plastic particle between paper fibers.This method increase 30 percent the strength of product.This product has a good sound proof and thermal isolation. This means we can use it as insulator.with low density we can control the the density by percentage of air solved in pulp.

Keywords: recycling, disposable coffee cup, insolator, low density

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8656 Assessing Land Cover Change Trajectories in Olomouc, Czech Republic

Authors: Mukesh Singh Boori, Vít Voženílek

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Olomouc is a unique and complex landmark with widespread forestation and land use. This research work was conducted to assess important and complex land use change trajectories in Olomouc region. Multi-temporal satellite data from 1991, 2001 and 2013 were used to extract land use/cover types by object oriented classification method. To achieve the objectives, three different aspects were used: (1) Calculate the quantity of each transition; (2) Allocate location based landscape pattern (3) Compare land use/cover evaluation procedure. Land cover change trajectories shows that 16.69% agriculture, 54.33% forest and 21.98% other areas (settlement, pasture and water-body) were stable in all three decade. Approximately 30% of the study area maintained as a same land cove type from 1991 to 2013. Here broad scale of political and socio-economic factors was also affect the rate and direction of landscape changes. Distance from the settlements was the most important predictor of land cover change trajectories. This showed that most of landscape trajectories were caused by socio-economic activities and mainly led to virtuous change on the ecological environment.

Keywords: remote sensing, land use/cover, change trajectories, image classification

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8655 DNA Isolation and Identification of Virulence Factors of Escherichia coli and Salmonella Species Isolated from Fresh Vegetables in Phnom Penh

Authors: Heng Sreyly, Phoeurk Chanrith

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Fresh-eaten vegetables have become more popular in the Cambodian diet. However, according to WHO, these vegetables should be one of the main sources of infection if contaminated with pathogenic microorganisms. The outbreaks of foodborne diseases related to fresh fruits and vegetables have been increasingly reported and raised concerns regarding the safety of these products. Therefore, it is very important to conduct the determination of virulence factors Escherichia coli and Salmonella spp. in fresh vegetables. This study aims to identify virulence strains of Escherichia coli and Salmonella species from fresh vegetables, including cucumber (Cucumis sativus), saw-herb (Eryngium foetidum), and lettuce (Lactuca sativa) from different market and supermarket in Phnom Penh. The PCR method was used to detect the virulence strains of each sample. The results indicate that there are ninety five samples containing extracted DNA among one hundred and three samples. Moreover, the virulence strain of E. coli and salmonella have been found in leafy vegetables (lettuce and saw-herb) much more than in fruit vegetables (cucumber). This research is mainly used to raise public awareness of washing fresh vegetables with clean water more carefully to reduce adverse health impacts.

Keywords: DNA, virulence factor, Escherichia coli, Salmonella

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8654 Alternative Animal Feed Additive Obtain with Different Drying Methods from Carrot Unsuitable for Human Consumption

Authors: Rabia Göçmen, Gülşah Kanbur, Sinan Sefa Parlat

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This study was conducted to determine that carrot powder obtain by different drying methods (oven and vacuum-freeze dryer) of carrot unfit for human consumption that whether feed additives in animal nutrition or not. Carrots randomly divided 2 groups. First group was dried by using oven, second group was by using vacuum freeze dryer methods. Dried carrot prepared from fresh carrot was analysed nutrient matter (energy, crude protein, crude oil, crude ash, beta carotene, mineral concentration and colour). The differences between groups in terms of energy, crude protein, ash, Ca and Mg was not significant (P> 0,05). Crude oil, P, beta carotene content and colour values (L, a, b) with vacuum-freeze dryer group was greater than oven group (P<0,05). Consequently, carrot powder obtained by drying the vacuum-freeze dryer method can be used as a source of carotene.

Keywords: carrot, vacuum freeze dryer, oven, beta carotene

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8653 Mechanical and Physical Properties of Aluminum Composite Reinforced with Carbon Nano Tube Dispersion via Ultrasonic and Ball Mill Attrition after Sever Plastic Deformation

Authors: Hassan Zare, Mohammad Jahedi, Mohammad Reza Toroghinejad, Mahmoud Meratian, Marko Knezevic

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In this study, the carbon nanotube (CNT) reinforced Al matrix nanocomposites were fabricated by ECAP. Equal Channel Angular Pressing (ECAP) process is one of the most important methods for powder densification due to the presence of shear strain. This method samples with variety passes (one, two, four and eight passes) in C route were prepared at room temperature. A few study about metal matrix nanocomposite reinforced carbon nanotube done, the reaction intersection of interface and carbon nanotube cause to reduce the efficiency of nanocomposite. In this paper, we checked mechanical and physical properties of aluminum-CNT composite that manufactured by ECAP when the composite is deformed. The non-agglomerated CNTs were distributed homogeneously with 2% consolidation in the Aluminum matrix. The ECAP process was performed on the both monolithic and composite with distributed CNT samples for 8 passes.

Keywords: powder metallurgy, ball mill attrition, ultrasonic, consolidation

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8652 Retrospective Demographic Analysis of Patients Lost to Follow-Up from Antiretroviral Therapy in Mulanje Mission Hospital, Malawi

Authors: Silas Webb, Joseph Hartland

Abstract:

Background: Long-term retention of patients on ART has become a major health challenge in Sub-Saharan Africa (SSA). In 2010 a systematic review of 39 papers found that 30% of patients were no longer taking their ARTs two years after starting treatment. In the same review, it was noted that there was a paucity of data as to why patients become lost to follow-up (LTFU) in SSA. This project was performed in Mulanje Mission Hospital in Malawi as part of Swindon Academy’s Global Health eSSC. The HIV prevalence for Malawi is 10.3%, one of the highest rates in the world, however prevalence soars to 18% in the Mulanje. Therefore it is essential that patients at risk of being LTFU are identified early and managed appropriately to help them continue to participate in the service. Methodology: All patients on adult antiretroviral formulations at MMH, who were classified as ‘defaulters’ (patients missing a scheduled follow up visit by more than two months) over the last 12 months were included in the study. Demographic varibales were collected from Mastercards for data analysis. A comparison group of patients currently not lost to follow up was created by using all of the patients who attended the HIV clinic between 18th-22nd July 2016 who had never defaulted from ART. Data was analysed using the chi squared (χ²) test, as data collected was categorical, with alpha levels set at 0.05. Results: Overall, 136 patients had defaulted from ART over the past 12 months at MMH. Of these, 43 patients had missing Mastercards, so 93 defaulter datasets were analysed. In the comparison group 93 datasets were also analysed and statistical analysis done using Chi-Squared testing. A higher proportion of men in the defaulting group was noted (χ²=0.034) and defaulters tended to be younger (χ²=0.052). 94.6% of patients who defaulted were taking Tenofovir, Lamivudine and Efavirenz, the standard first line ART therapy in Malawi. The mean length of time on ART was 39.0 months (RR: -22.4-100.4) in the defaulters group and 47.3 months (RR: -19.71-114.23) in the control group, with a mean difference of 8.3 less months in the defaulters group (χ ²=0.056). Discussion: The findings in this study echo the literature, however this review expands on that and shows the demographic for the patient at most risk of defaulting and being LTFU would be: a young male who has missed more than 4 doses of ART and is within his first year of treatment. For the hospital, this data is important at it identifies significant areas for public health focus. For instance, fear of disclosure and stigma may be disproportionately affecting younger men, so interventions can be aimed specifically at them to improve their health outcomes. The mean length of time on medication was 8.3 months less in the defaulters group, with a p-value of 0.056, emphasising the need for more intensive follow-up in the early stages of treatment, when patients are at the highest risk of defaulting.

Keywords: anti-retroviral therapy, ART, HIV, lost to follow up, Malawi

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8651 Automated Tracking and Statistics of Vehicles at the Signalized Intersection

Authors: Qiang Zhang, Xiaojian Hu1

Abstract:

Intersection is the place where vehicles and pedestrians must pass through, turn and evacuate. Obtaining the motion data of vehicles near the intersection is of great significance for transportation research. Since there are usually many targets and there are more conflicts between targets, this makes it difficult to obtain vehicle motion parameters in traffic videos of intersections. According to the characteristics of traffic videos, this paper applies video technology to realize the automated track, count and trajectory extraction of vehicles to collect traffic data by roadside surveillance cameras installed near the intersections. Based on the video recognition method, the vehicles in each lane near the intersection are tracked with extracting trajectory and counted respectively in various degrees of occlusion and visibility. The performances are compared with current recognized CPU-based algorithms of real-time tracking-by-detection. The speed of the presented system is higher than the others and the system has a better real-time performance. The accuracy of direction has reached about 94.99% on average, and the accuracy of classification and statistics has reached about 75.12% on average.

Keywords: tracking and statistics, vehicle, signalized intersection, motion parameter, trajectory

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8650 The Effects of Self-Reflections on Intercultural Communication Competency: A Case Study of the University of Arkansas-Fort Smith

Authors: JaeYoon Park

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The ability to communicate effectively across different cultures is a necessary skill in today’s increasingly globalized world. Intercultural communication competency (ICC) is a way of being that benefits all members of a society in their living, learning, and working environments as well as in the context of mediated communications. This study examines the effects of self-reflection processes on the improvement of intercultural communication skills focusing on college students at the University of Arkansas-Fort Smith. A total of sixty-nine students’ works were analyzed based on the data collected in the past three years (2016, 2017 and 2018). The students in the ‘Culture and Communication’ class, each spring, completed the Diversity Awareness Profile (DAP) survey as a pre- and post-test for the course. DAP is a self-assessment tool designed by Karen Stinson and widely used in college classes, companies, and organizations to evaluate an individual’s behaviors in various intercultural settings. It can assist individuals in becoming more aware of diversity issues and also provide a foundation for developing strategies for modifying any undesirable behavior they may discover in the assessment. In addition to the DAP surveys, the students also submitted self-reflection essays that discussed their own scores. The University of Arkansas-Fort Smith is a small regional university located in the Bible Belt of the United States. White, Christian, working-class students dominate its student population. The students, whose data were collected, were predominantly seniors in college majoring in either Media Communication or International Business. Approximately, 80% of the students increased their scores, and 42% of them moved forward to a new category. The findings also indicate that the students in the underrepresented groups (i.e., women, minority, and international students) show less change in their scores and behaviors than the rest of the students (i.e., white heterosexual male students). These findings, in most part, result from the fact that the underrepresented students were already aware of diversity and intercultural issues through their personal experiences before taking the class. The white heterosexual male students demonstrated the greatest improvements, judging from their DAP scores (pre- and post-tests) and self-reflection essays. Through the class assignments and discussions, which emphasized critical thinking and self-reflection, the latter group of students not only became more aware of the meaning of their own words and behaviors, but they were also able to develop greater proficiency in intercultural communication. This e-poster presentation will analyze the findings of this research data, and also discuss the pedagogical implications of such results.

Keywords: cross-cultural communication, diversity awareness survey, self-reflection, underrepresented students

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8649 Effects of Elastic, Plyometric and Strength Training on Selected Anaerobic Factors in Sanandaj Elite Volleyball Players

Authors: Majed Zobairy, Fardin Kalvandi, Kamal Azizbaigi

Abstract:

This research was carried out for evaluation of elastic, plyometric and resistance training on selected anaerobic factors in men volleyball players. For these reason 30 elite volleyball players of Sanandaj city randomly divided into 3 groups as follow: elastic training, plyometric training and resistance training. Pre-exercise tests which include vertical jumping, 50 yard speed running and scat test were done and data were recorded. Specific exercise protocol regimen was done for each group and then post-exercise tests again were done. Data analysis showed that there were significant increases in exercise test in each group. One way ANOVA analysis showed that increases in speed records in elastic group were significantly higher than the other groups (p<0/05),based on research data it seems that elastic training can be a useful method and new approach in improving functional test and training regimen.

Keywords: elastic training, plyometric training, strength training, anaerobic power

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8648 Corrosion Characterization of Al6061, Quartz Metal Matrix Composites in Alkali Medium

Authors: Radha H. R., Krupakara P. V.

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Metal matrix composites are attracting today's manufacturers of many automobile parts so that they lost longer and their properties can be tailored according to the requirement. In this paper an attempt has been made to study the corrosion characteristics of Aluminium 6061 / quartz metal matrix composites in alkali medium like sodium hydroxide solutions. Metal matrix composites are heterogeneous mixtures of a matrix and reinforcement. In this work the matrix selected is Aluminium 6061 alloy which is commercially available and the reinforcement selected is quartz particulates of 50-80 micron size which is available in plenty in and around Bangalore district, India. Composites containing Aluminium 6061 with 2, 4 and 6 weight percent of quartz are manufactured by liquid melt metallurgy technique using vortex method. Corrosion tests like static weight loss and open circuit potential tests are conducted in different concentrated solutions of sodium hydroxide. To compare the results the matrix Aluminium 6061 is also casted in the same way. Specimens for the test are prepared according to ASTM standards. In all the tests the metal matrix composites showed better corrosion resistance than matrix alloy.

Keywords: aluminium 6061, corrosion, quartz, vortex

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8647 Adaptive Control of Magnetorheological Damper Using Duffing-Like Model

Authors: Hung-Jiun Chi, Cheng-En Tsai, Jia-Ying Tu

Abstract:

Semi-active control of Magnetorheological (MR) dampers for vibration reduction of structural systems has received considerable attention in civil and earthquake engineering, because the effective stiffness and damping properties of MR fluid can change in a very short time in reaction to external loading, requiring only a low level of power. However, the inherent nonlinear dynamics of hysteresis raise challenges in the modeling and control processes. In order to control the MR damper, an innovative Duffing-like equation is proposed to approximate the hysteresis dynamics in a deterministic and systematic manner than previously has been possible. Then, the model-reference adaptive control technique based on the Duffing-like model and the Lyapunov method is discussed. Parameter identification work with experimental data is presented to show the effectiveness of the Duffing-like model. In addition, simulation results show that the resulting adaptive gains enable the MR damper force to track the desired response of the reference model satisfactorily, verifying the effectiveness of the proposed modeling and control techniques.

Keywords: magnetorheological damper, duffing equation, model-reference adaptive control, Lyapunov function, hysteresis

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8646 Utilization of Chicken Skin Based Products as Fat Replacers for Improving the Nutritional Quality, Physico-Chemical Characteristics and Sensory Attributes of Beef Fresh Sausage

Authors: Hussein M. H. Mohamed, Hamdy M. B. Zaki

Abstract:

Fresh sausage is one of the cheapest and delicious meat products that are gaining popularity all over the world. It is considered as a practice of adding value to low-value meat cuts of high fat and connective tissue contents. One of the most important characteristics of fresh sausage is the distinctive marbling appearance between lean and fatty portions, which can be achieved by using animal fat. For achieving the marbling appearance of fresh sausage, a lager amount of fat needs to be used. The use of animal fat may represent a health concern due to its content of saturated fatty acids and trans-fats, which increase the risk of heart diseases. There is a need for reducing the fat content of fresh sausage to obtain a healthy product. However, fat is responsible for the texture, flavor, and juiciness of the product. Therefore, developing reduced-fat products is a challenging process. The main objectives of the current study were to incorporate chicken skin based products (chicken skin emulsion, gelatinized chicken skin, and gelatinized chicken skin emulsion) during the formulation of fresh sausage as fat replacers and to study the effect of these products on the nutritional quality, physicochemical properties, and sensory attributes of the processed product. Three fresh sausage formulae were prepared using chicken skin based fat replacers (chicken skin emulsion, gelatinized chicken skin, and gelatinized chicken skin emulsion) beside one formula prepared using mesenteric beef fat as a control. The proximate composition, fatty acid profiles, Physico-chemical characteristics, and sensory attributes of all formulas were assessed. The results revealed that the use of chicken skin based fat replacers resulted in significant (P < 0.05) reduction of fat contents from 17.67 % in beef mesenteric fat formulated sausage to 5.77, 8.05 and 8.46 in chicken skin emulsion, gelatinized chicken skin, and gelatinized chicken skin emulsion formulated sausages, respectively. Significant reduction in the saturated fatty acid contents and a significant increase in mono-unsaturated, poly-unsaturated, and omega-3 fatty acids have been observed in all formulae processed with chicken skin based fat replacers. Moreover, significant improvements in the physico-chemical characteristics and non-significant changes in the sensory attributes have been obtained. From the obtained results, it can be concluded that the chicken skin based products can be used safely to improve the nutritional quality and physico chemical properties of beef fresh sausages without changing the sensory attributes of the product. This study may encourage meat processors to utilize chicken skin based fat replacers for the production of high quality and healthy beef fresh sausages.

Keywords: chicken skin emulsion, fresh sausage, gelatinized chicken skin, gelatinized chicken skin emulsion

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8645 Multi-Dimensional (Quantatative and Qualatative) Longitudinal Research Methods for Biomedical Research of Post-COVID-19 (“Long Covid”) Symptoms

Authors: Steven G. Sclan

Abstract:

Background: Since December 2019, the world has been afflicted by the spread of the Severe Acute Respiratory Syndrome-Corona Virus-2 (SARS-CoV-2), which is responsible for the condition referred to as Covid-19. The illness has had a cataclysmic impact on the political, social, economic, and overall well-being of the population of the entire globe. While Covid-19 has had a substantial universal fatality impact, it may have an even greater effect on the socioeconomic, medical well-being, and healthcare planning for remaining societies. Significance: As these numbers illustrate, many more persons survive the infection than die from it, and many of those patients have noted ongoing, persistent symptoms after successfully enduring the acute phase of the illness. Recognition and understanding of these symptoms are crucial for developing and arranging efficacious models of care for all patients (whether or not having been hospitalized) surviving acute covid illness and plagued by post-acute symptoms. Furthermore, regarding Covid infection in children (< 18 y/o), although it may be that Covid “+” children are not major vectors of infective transmission, it now appears that many more children than initially thought are carrying the virus without accompanying obvious symptomatic expression. It seems reasonable to wonder whether viral effects occur in children – those children who are Covid “+” and now asymptomatic – and if, over time, they might also experience similar symptoms. An even more significant question is whether Covid “+” asymptomatic children might manifest increased multiple health problems as they grow – i.e., developmental complications (e.g., physical/medical, metabolic, neurobehavioral, etc.) – in comparison to children who had been consistently Covid “ - ” during the pandemic. Topics Addressed and Theoretical Importance: This review is important because of the description of both quantitative and qualitative methods for clinical and biomedical research. Topics reviewed will consider the importance of well-designed, comprehensive (i.e., quantitative and qualitative methods) longitudinal studies of Post Covid-19 symptoms in both adults and children. Also reviewed will be general characteristics of longitudinal studies and a presentation of a model for a proposed study. Also discussed will be the benefit of longitudinal studies for the development of efficacious interventions and for the establishment of cogent, practical, and efficacious community healthcare service planning for post-acute covid patients. Conclusion: Results of multi-dimensional, longitudinal studies will have important theoretical implications. These studies will help to improve our understanding of the pathophysiology of long COVID and will aid in the identification of potential targets for treatment. Such studies can also provide valuable insights into the long-term impact of COVID-19 on public health and socioeconomics.

Keywords: COVID-19, post-COVID-19, long COVID, longitudinal research, quantitative research, qualitative research

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8644 The Diagnostic Utility and Sensitivity of the Xpert® MTB/RIF Assay in Diagnosing Mycobacterium tuberculosis in Bone Marrow Aspirate Specimens

Authors: Nadhiya N. Subramony, Jenifer Vaughan, Lesley E. Scott

Abstract:

In South Africa, the World Health Organisation estimated 454000 new cases of Mycobacterium tuberculosis (M.tb) infection (MTB) in 2015. Disseminated tuberculosis arises from the haematogenous spread and seeding of the bacilli in extrapulmonary sites. The gold standard for the detection of MTB in bone marrow is TB culture which has an average turnaround time of 6 weeks. Histological examinations of trephine biopsies to diagnose MTB also have a time delay owing mainly to the 5-7 day processing period prior to microscopic examination. Adding to the diagnostic delay is the non-specific nature of granulomatous inflammation which is the hallmark of MTB involvement of the bone marrow. A Ziehl-Neelson stain (which highlights acid-fast bacilli) is therefore mandatory to confirm the diagnosis but can take up to 3 days for processing and evaluation. Owing to this delay in diagnosis, many patients are lost to follow up or remain untreated whilst results are awaited, thus encouraging the spread of undiagnosed TB. The Xpert® MTB/RIF (Cepheid, Sunnyvale, CA) is the molecular test used in the South African national TB program as the initial diagnostic test for pulmonary TB. This study investigates the optimisation and performance of the Xpert® MTB/RIF on bone marrow aspirate specimens (BMA), a first since the introduction of the assay in the diagnosis of extrapulmonary TB. BMA received for immunophenotypic analysis as part of the investigation into disseminated MTB or in the evaluation of cytopenias in immunocompromised patients were used. Processing BMA on the Xpert® MTB/RIF was optimised to ensure bone marrow in EDTA and heparin did not inhibit the PCR reaction. Inactivated M.tb was spiked into the clinical bone marrow specimen and distilled water (as a control). A volume of 500mcl and an incubation time of 15 minutes with sample reagent were investigated as the processing protocol. A total of 135 BMA specimens had sufficient residual volume for Xpert® MTB/RIF testing however 22 specimens (16.3%) were not included in the final statistical analysis as an adequate trephine biopsy and/or TB culture was not available. Xpert® MTB/RIF testing was not affected by BMA material in the presence of heparin or EDTA, but the overall detection of MTB in BMA was low compared to histology and culture. Sensitivity of the Xpert® MTB/RIF compared to both histology and culture was 8.7% (95% confidence interval (CI): 1.07-28.04%) and sensitivity compared to histology only was 11.1% (95% CI: 1.38-34.7%). Specificity of the Xpert® MTB/RIF was 98.9% (95% CI: 93.9-99.7%). Although the Xpert® MTB/RIF generates a faster result than histology and TB culture and is less expensive than culture and drug susceptibility testing, the low sensitivity of the Xpert® MTB/RIF precludes its use for the diagnosis of MTB in bone marrow aspirate specimens and warrants alternative/additional testing to optimise the assay.

Keywords: bone marrow aspirate , extrapulmonary TB, low sensitivity, Xpert® MTB/RIF

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8643 Nanoindentation Behavior and Physical Properties of Polyvinyl Chloride /Styrene Co-Maleic Anhydride Blend Reinforced by Nano-Bentonite

Authors: Dalia Elsawy Abulyazied, Samia Mohamad Mokhtar, Ahmed Magdy Motawie

Abstract:

This article studies the effects of nano-bentonite on the structure and properties of polymer blends nanocomposites, based on polyvinyl chloride (PVC) and styrene co-maleic anhydride (SMA) blend. Modification of Egyptian bentonite (EB) is carried out using organo-modifier namely; octadecylamine (ODA). Octadecylamine bentonite (ODA-B) is characterized using FTIR, XRD and TEM. Nanocomposites of PVC/SMA/ODA-B are prepared by solution intercalation polymerization from 0.50 up to 5 phr. The nanocomposites are characterized by XRD and TEM. Thermal behavior of the nanocomposites is studied. The effect of different content of ODA-B on the nano-mechanical properties is investigated by a nano-indentation test method. Also the swelling and electrical properties of the nanocomposites are measured. The morphology of the nanocomposites shows that ODA-B achieved good dispersion in the PVC/SMA matrix. The thermal stability of the nanocomposites is enhanced due to the presence of the ODA-B. Incorporation of 0.5, 1, 3 and 5 phr. ODA-B into the PVC/SMA blends results in an improvement in nano-hardness of 16%, 76%, 92%, and 68% respectively. The elastic modulus increased by 37% from 4.59 GPa for unreinforced PVC/SMA blend to 6.30 GPa for 3 phr. The cross-link density and the electrical conductivity of the nanocomposites are increased with increasing the content of ODA-B.

Keywords: PVC, SMA, nanocomposites, nano-bentonite, nanoindentation, crosslink density

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8642 Determination of the Presence of Antibiotic Resistance from Vibrio Species in Northern Italy

Authors: Tramuta Clara, Masotti Chiara, Pitti Monica, Adriano Daniela, Battistini Roberta, Serraca Laura, Decastelli Lucia

Abstract:

Oysters are considered filter organisms, and their raw consumption may increase health risks for consumers: it is often associated with outbreaks of gastroenteritis or enteric illnesses. Most of these foodborne diseases are caused by Vibrio strains, enteric pathogens also involved in the diffusion of genetic determinants of antibiotic resistance and their entrance along the food chain. The European Food Safety Authority (EFSA), during the European Union report on antimicrobial resistance in 2017, focused the attention about the role of food as a possible carrier of antibiotic-resistant bacteria or antibiotic-resistance genes that determine health risks for humans. This study wants to determine antibiotic resistance and antibiotic-resistance genes in Vibrio spp. isolated from Crassostrea gigas oysters collected in the Golfo della Spezia (Liguria, Italy). A total of 47 Vibrio spp. strains were isolated (ISO21872-2:2017) during the summer of 2021 from oysters of Crassostrea gigas. The strains were identified by MALDI-TOF (Bruker, Germany) mass spectrometry and tested for antibiotic susceptibility using a broth microdiluition method (ISO20776-1:2019) using Sensititre EUVSEC plates (Thermo-Fisher Scientific) to obtain the Minimum Inhibitory Concentration (MIC). The strains were tested with PCR-based biomolecular methods, according to previous works, to define the presence of 23 resistance genes of the main classes of antibiotics used in human and veterinary medicine: tet (B), tet (C), tet (D), tet (A), tet (E), tet (G ), tet (K), tet (L), tet (M), tet (O), tet (S) (tetracycline resistance); blaCTX-M, blaTEM, blaOXA, blaSHV (β-lactam resistance); mcr-1 and mcr-2 (colistin resistance); qnrA, qnrB, and qnrS (quinolone resistance); sul1, sul2 and sul3 (sulfonamide resistance). Six different species have been identified: V. alginolyticus 34% (n=16), V. harveyi 28% (n=13), V. fortis 15% (n=7), V. pelagius 8% (n=4), V. parahaemolyticus 11% (n=5) e V. chagasii 4% (n=2). The PCR assays showed the presence of the blaTEM gene on 40% of the strains (n=19). All the other genes were not detected, except for a V. alginolyticus positive for anrS gene. The broth microdiluition method results showed an high level of resistance for ciprofloxacin (62%; n=29), ampicillin (47%; n=22), and colistin (49%; n=23). Furthermore, 32% (n=15) of strains can be considered multiresistant bacteria for the simultaneous presence of resistance for three different antibiotic classes. Susceptibility towards meropenem, azithromycin, gentamicin, ceftazidime, cefotaxime, chloramphenicol, tetracycline and sulphamethoxazole reached 100%. The Vibrio species identified in this study are widespread in marine environments and can cause gastrointerstinal infections after the ingestion of raw fish products and bivalve molluscs. The level of resistance to antibiotics such as ampicillin, ciprofloxacin and colistin can be connected to anthropic factors (industrial, agricultural and domestic wastes) that promote the spread of resistance to these antibiotics. It can be also observed a strong correlation between phenotypic (resistant MIC) and genotypic (positive blaTEM gene) resistance for ampicillin on the same strains, probably due to the transfer of genetic material between bacterial strains. Consumption of raw bivalve molluscs can represent a risk for consumers heath due to the potentially presence of foodborne pathogens, highly resistant to different antibiotics and source of transferable antibiotic-resistant genes.

Keywords: vibrio species, blaTEM genes, antimicrobial resistance, PCR

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8641 An Evaluation of Impact of Media on the Electoral Reform Process in Nigeria between 2010–2015

Authors: H. Shola Adeosun, D. Adeoye Odedeji, F. Ajoke Adebiyi

Abstract:

This study examines the impact of media on the electoral process in Nigeria and the roles played by the media in the reform process. Survey research method was adopted as research methodology, and this enables the researcher to use questionnaire, and oral interview to elicit primary data from the respondents was interpreted, analysed and interpreted with statistical tools such as tables, figures, and percentages. The hypothesis formulated were tested with chi-square. The findings revealed that there is significant relationship between the media and electoral reform process in the 2011 and 2015 general elections in Nigeria. The study recommends that electoral committee should implement virile electoral system with the peaceful voting environment. The media should intensify efforts to expose violation of electoral laws; media should play an advocacy role for dialogue and debate on the reform recommendations. The study recommends that media should unite the nation through their reports on peace, national security, national integration and ethnoreligious tolerance and that adequate training should be given to media practitioners on how to report issues relating to elections.

Keywords: evaluation, impact, media, electoral reform process

Procedia PDF Downloads 283
8640 Early Influences on Teacher Identity: Perspectives from the USA and Northern Ireland

Authors: Martin Hagan

Abstract:

Teacher identity has been recognised as a crucial field of research which supports understanding of the ways in which teachers navigate the complexities of professional life in order to grow in competence, knowledge and practice. As a field of study, teacher identity is concerned with understanding: how identity is defined; how it develops; how teachers make sense of their emerging identity; and how the act of teaching is mediated through the individual teacher’s values, beliefs and sense of professional self. By comparing two particular, socially constructed learning contexts or ‘learning milieu’, one in Northern Ireland and the other in the United States of America, this study aims specifically, to gain better understanding of how teacher identity develops during the initial phase of teacher education. The comparative approach was adopted on the premise that experiences are constructed through interactive, socio-historical and cultural negotiations with others within particular environments, situations and contexts. As such, whilst the common goal is to ‘become’ a teacher, the nuances emerging from the different learning milieu highlight variance in discourse, priorities, practice and influence. A qualitative, interpretative research design was employed to understand the world-constructions of the participants through asking open-ended questions, seeking views and perspectives, examining contexts and eventually deducing meaning. Data were collected using semi structured interviews from a purposive sample of student teachers (n14) in either the first or second year of study in their respective institutions. In addition, a sample of teacher educators (n5) responsible for the design, organisation and management of the programmes were also interviewed. Inductive thematic analysis was then conducted, which highlighted issues related to: the participants’ personal dispositions, prior learning experiences and motivation; the influence of the teacher education programme on the participants’ emerging professional identity; and the extent to which the experiences of working with teachers and pupils in schools in the context of the practicum, challenged and changed perspectives on teaching as a professional activity. The study also highlights the varying degrees of influence exercised by the different roles (tutor, host teacher/mentor, student) within the teacher-learning process across the two contexts. The findings of the study contribute to the understanding of teacher identity development in the early stages of professional learning. By so doing, the research makes a valid contribution to the discourse on initial teacher preparation and can help to better inform teacher educators and policy makers in relation to appropriate strategies, approaches and programmes to support professional learning and positive teacher identity formation.

Keywords: initial teacher education, professional learning, professional growth, teacher identity

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8639 An Alternative and Complementary Medicine Method in Vulnerable Pediatric Cancer Patients: Yoga

Authors: Ç. Erdoğan, T. Turan

Abstract:

Pediatric cancer patients experience multiple distressing, challenges, physical symptom such as fatigue, pain, sleep disturbance, and balance impairment that continue years after treatment completion. In recent years, yoga is often used in children with cancer to cope with these symptoms. Yoga practice is defined as a unique physical activity that combines physical practice, breath work and mindfulness/meditation. Yoga is an increasingly popular mind-body practice also characterized as a mindfulness mode of exercise. This study aimed to evaluate the impact of yoga intervention of children with cancer. This article planned searching the literature in this field. It has been determined that individualized yoga is feasible and provides benefits for inpatient children, improves health-related quality of life, physical activity levels, physical fitness. After yoga program, children anxiety score decreases significantly. Additionally, individualized yoga is feasible for inpatient children receiving intensive chemotherapy. As a result, yoga is an alternative and complementary medicine that can be safely used in children with cancer.

Keywords: cancer treatment, children, nursing, yoga

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8638 Smart Lean Manufacturing in the Context of Industry 4.0: A Case Study

Authors: M. Ramadan, B. Salah

Abstract:

This paper introduces a framework to digitalize lean manufacturing tools to enhance smart lean-based manufacturing environments or Lean 4.0 manufacturing systems. The paper discusses the integration between lean tools and the powerful features of recent real-time data capturing systems with the help of Information and Communication Technologies (ICT) to develop an intelligent real-time monitoring and controlling system of production operations concerning lean targets. This integration is represented in the Lean 4.0 system called Dynamic Value Stream Mapping (DVSM). Moreover, the paper introduces the practice of Radio Frequency Identification (RFID) and ICT to smartly support lean tools and practices during daily production runs to keep the lean system alive and effective. This work introduces a practical description of how the lean method tools 5S, standardized work, and poka-yoke can be digitalized and smartly monitored and controlled through DVSM. A framework of the three tools has been discussed and put into practice in a German switchgear manufacturer.

Keywords: lean manufacturing, Industry 4.0, radio frequency identification, value stream mapping

Procedia PDF Downloads 222
8637 Combining Impedance and Hydrodynamic Methods toward Hydrogen Evolution Reaction to Characterize Pt(pc), Pt5Gd, and Nanostructure Pd Electrocatalyst

Authors: Kun-Ting Song, Christian Schott, Peter Schneider, Sebastian Watzele, Regina Kluge, Elena Gubanova, Aliaksandr S. Bandarenka

Abstract:

The combination of electrochemical impedance spectroscopy (EIS) and the hydrodynamic technique like rotation disc electrode (RDE) provides a critical method for quantitively investigating mechanisms of hydrogen evolution reaction (HER) in acidic and alkaline media. Pt5Gd represented higher HER activities than polycrystalline Pt (Pt(pc)) by means of the surface strain effects. The model of the equivalent electric circuit to fit the impedance data under the RDE configurations is developed. To investigate the relative reaction contribution, the ratio of the charge transfer reactions of the Volmer-Heyrovsky and Volmer-Tafel pathways on Pt and Pt5Gd electrodes is determined. The ratio remains comparably similar in acidic media, but it changes in alkaline media with Volmer–Heyrovsky pathway dominating. This combined approach of EIS and RDE can help to study the electrolyte effects and other essential reactions for electrocatalysis in future work.

Keywords: hydrogen evolution reaction, electrochemical impedance spectroscopy, hydrodynamic methods, electrocatalysis, electrochemical interface

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8636 Nanoarchitectures Cu2S Functions as Effective Surface-Enhanced Raman Scattering Substrates for Molecular Detection Application

Authors: Yu-Kuei Hsu, Ying-Chu Chen, Yan-Gu Lin

Abstract:

The hierarchical Cu2S nano structural film is successfully fabricated via an electroplated ZnO nanorod array as a template and subsequently chemical solution process for the growth of Cu2S in the application of surface-enhanced Raman scattering (SERS) detection. The as-grown Cu2S nano structures were thermally treated at temperature of 150-300 oC under nitrogen atmosphere to improve the crystal quality and unexpectedly induce the Cu nano particles on surface of Cu2S. The structure and composition of thermally treated Cu2S nano structures were carefully analyzed by SEM, XRD, XPS, and XAS. Using 4-aminothiophenol (4-ATP) as probing molecules, the SERS experiments showed that the thermally treated Cu2S nano structures exhibit excellent detecting performance, which could be used as active and cost-effective SERS substrate for ultra sensitive detecting. Additionally, this novel hierarchical SERS substrates show good reproducibility and a linear dependence between analyte concentrations and intensities, revealing the advantage of this method for easily scale-up production.

Keywords: cuprous sulfide, copper, nanostructures, surface-enhanced raman scattering

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8635 InP/ZnS Core-Shell and InP/ZnS/ZnS Core-Multishell Quantum Dots for Improved luminescence Efficiency

Authors: Imen Harabi, Hanae Toura, Safa Jemai, Bernabe Mari Soucase

Abstract:

A promising alternative to traditional Quantum Dots QD materials, which contain toxic heavy elements such as lead and cadmium, sheds light on indium phosphide quantum dots (InP QDs) Owing to improve the quantum yields of photoluminescence and other properties. InP, InP/ZnS core/shell and InP/ZnS/ZnS core/shell/shell Quantum Dots (QDs) were synthetized by the hot injection method. The optical and structural properties of the core InP QDs, InP/ZnS QDs, and InP/ZnS/ZnS QDs have being considered by several techniques such as X-ray diffraction, transmission electron microscopy, optical spectroscopy, and photoluminescence. The average diameter of InP, InP/ZnS, and InP/ZnS/ZnS Quantum Dots (QDs) was varying between 10 nm, 5.4 nm, and 4.10 nm. This experience revealed that the surface morphology of the Quantum Dots has a more regular spherical form with color variation of the QDs in solution. The emission peak of colloidal InP Quantum Dots was around 530 nm, while in InP/ZnS, the emission peak is displayed and located at 598 nm. whilst for InP/ZnS/ZnS is placed at 610 nm. Furthermore, an enhanced PL emission due to a passivation effect in the ZnS-covered InP QDs was obtained. Add the XRD information FWHM of the principal peak of InP QDs was 63 nm, while for InP/ZnS was 41 nm and InP/ZnS/ZnS was 33 nm. The effect of the Zinc stearate precursor concentration on the optical, structural, surface chemical of InP and InP/ZnS and InP/ZnS/ZnS QDs will be discussed.

Keywords: indium phosphide, quantum dot, nanoparticle, core-shell, multishell, luminescence

Procedia PDF Downloads 157