Search results for: performance and quality
4542 Ultrathin Tin-Silicalite 1 Zeolite Membrane in Ester Solvent Recovery
Authors: Kun Liang Ang, Eng Toon Saw, Wei He, Xuecheng Dong, Seeram Ramakrishna
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Ester solvents are widely used in pharmaceutical, printing and flavor industry due to their good miscibility, low toxicity, and high volatility. Through pervaporation, these ester solvents can be recovered from industrial wastewater. While metal-doped silicalite 1 zeolite membranes are commonly used in organic solvent recovery in the pervaporation process, these ceramic membranes suffer from low membrane permeation flux, mainly due to the high thickness of the metal-doped zeolite membrane. Herein, a simple method of fabricating an ultrathin tin-silicalite 1 membrane supported on alumina tube is reported. This ultrathin membrane is able to achieve high permeation flux and separation factor for an ester in a diluted aqueous solution. Nanosized tin-Silicalite 1 seeds which are smaller than 500nm has been formed through hydrothermal synthesis. The sn-Silicalite 1 seeds were then seeded onto alumina tube through dip coating, and the tin-Silicalite 1 membrane was then formed by hydrothermal synthesis in an autoclave through secondary growth method. Multiple membrane synthesis factors such as seed size, ceramic substrate surface pore size selection, and secondary growth conditions were studied for their effects on zeolite membrane growth. The microstructure, morphology and the membrane thickness of tin-Silicalite 1 zeolite membrane were examined. The membrane separation performance and stability will also be reported.Keywords: ceramic membrane, pervaporation, solvent recovery, Sn-MFI zeolite
Procedia PDF Downloads 1934541 Construction 4.0: The Future of the Construction Industry in South Africa
Authors: Temidayo. O. Osunsanmi, Clinton Aigbavboa, Ayodeji Oke
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The construction industry is a renowned latecomer to the efficiency offered by the adoption of information technology. Whereas, the banking, manufacturing, retailing industries have keyed into the future by using digitization and information technology as a new approach for ensuring competitive gain and efficiency. The construction industry has yet to fully realize similar benefits because the adoption of ICT is still at the infancy stage with a major concentration on the use of software. Thus, this study evaluates the awareness and readiness of construction professionals towards embracing a full digitalization of the construction industry using construction 4.0. The term ‘construction 4.0’ was coined from the industry 4.0 concept which is regarded as the fourth industrial revolution that originated from Germany. A questionnaire was utilized for sourcing data distributed to practicing construction professionals through a convenience sampling method. Using SPSS v24, the hypotheses posed were tested with the Mann Whitney test. The result revealed that there are no differences between the consulting and contracting organizations on the readiness for adopting construction 4.0 concepts in the construction industry. Using factor analysis, the study discovers that adopting construction 4.0 will improve the performance of the construction industry regarding cost and time savings and also create sustainable buildings. In conclusion, the study determined that construction professionals have a low awareness towards construction 4.0 concepts. The study recommends an increase in awareness of construction 4.0 concepts through seminars, workshops and training, while construction professionals should take hold of the benefits of adopting construction 4.0 concepts. The study contributes to the roadmap for the implementation of construction industry 4.0 concepts in the South African construction industry.Keywords: building information technology, Construction 4.0, Industry 4.0, smart site
Procedia PDF Downloads 4164540 Structural Performance Evaluation of Segmented Wind Turbine Blade Through Finite Element Simulation
Authors: Chandrashekhar Bhat, Dilifa Jossley Noronha, Faber A. Saldana
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Transportation of long turbine blades from one place to another is a difficult process. Hence a feasibility study of modularization of wind turbine blade was taken from structural standpoint through finite element analysis. Initially, a non-segmented blade is modeled and its structural behavior is evaluated to serve as reference. The resonant, static bending and fatigue tests are simulated in accordance with IEC61400-23 standard for comparison purpose. The non-segmented test blade is separated at suitable location based on trade off studies and the segments are joined with an innovative double strap bonded joint configuration. The adhesive joint is modeled by adopting cohesive zone modeling approach in ANSYS. The developed blade model is analyzed for its structural response through simulation. Performances of both the blades are found to be similar, which indicates that, efficient segmentation of the long blade is possible which facilitates easy transportation of the blades and on site reassembling. The location selected for segmentation and adopted joint configuration has resulted in an efficient segmented blade model which proves the methodology adopted for segmentation was quite effective. The developed segmented blade appears to be the viable alternative considering its structural response specifically in fatigue within considered assumptions.Keywords: modularization, fatigue, cohesive zone modeling, wind turbine blade
Procedia PDF Downloads 4544539 Reasonable Adjustment for Students with Disabilities - Opportunities and Limits in Social Work Education
Authors: Bartelsen-Raemy Annabelle, Gerber Andrea
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Objectives: The adoption of the UN Convention on the Rights of Persons with Disabilities has the effect that higher education institutions in Switzerland are called upon to promote inclusive university education. In this context, our School of Social Work aims to provide fair participation and the removal of barriers in our study programmes at bachelor’s and master’s levels. In 2015 we developed a concept of reasonable adjustments for students with disabilities and chronic illness as an instrument to provide equal opportunities for those students. We reviewed the implementation of this concept as part of our quality management process. Using a qualitative research design, we explored how affected students and lecturers experience the processes and measures taken and which barriers they still perceive. Methods: We captured subjective perspectives and experience of measures by conducting 15 problem-centred interviews with affected students and three experimental focus groups with lecturers. The data was processed using structured qualitative content analysis and summarised as key categories. Results: All respondents evaluated the concept of reasonable adjustment very positively and emphasised its importance for equal opportunities. Our analysis revealed differences in the usage and perception of both groups and showed that the students interviewed were a heterogeneous group with different needs. Overall, the students described the adjustments, in particular in relation to examinations and other assignments, as a great relief. The lecturers expressed high standards for their own teaching and supervision of students and, at the same time, wished for more support from the university. However, despite the positive evaluation by the lecturers, the limits of reasonable adjustment became evident. It is necessary to consider the limits of reasonable adjustments in terms of professional skills. Conclusion: Reasonable adjustments should, therefore, be seen as an element of an inclusive university culture that must be complemented by further measures. Taking this into account, we have planned further research as a basis for the development of a diversity and inclusion policy.Keywords: opportunities and limits, reasonable adjustment, social work education, students with disabilities
Procedia PDF Downloads 1354538 Suitability of Quarry Dust as Replacement of Sand in Medium Grade Concrete
Authors: Popoola M. Oyenola
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Concrete plays the important role and a huge percentage of concrete is being utilized in every construction practices. Natural river sand is one of the major ingredients of concrete, is becoming expensive due to excessive cost of accessibility from sources. Also large scale depletion of sources creates environmental problems. Therefore, there is a need of economic alternative materials. Quarry dust is a waste obtained during quarrying process. It has been rampantly used in different construction practices and could be used as an effective fine aggregate instead of river sand. Partial and total replacement of fine aggregate in conventional concrete with quarry dust has been empirically conducted with the view to examining primarily the compressive strength of the resulting composite and possible total utilization of quarry dust as fine aggregate in the production of medium grade concrete. The results of the study showed that its specific gravity, porosity and water absorption showed satisfactory performance. The percentage replacement of natural river sand with quarry dust for a designed strength of 25N/mm2 varied at intervals of 10% up to a maximum value of 100%. A total of 132 cubes of 150 x 150 x 150mm were cast and tested at 7, 14 and 28 days of hydration. Compressive strength increases with curing age in all the mixes. Compressive strength decreases with increase in percentage of quarry dust. Generally the compressive strength of concrete incorporating quarry dust attained strength of 22.47 N/mm2 after 28 days which makes it a suitable aggregate for the production medium grade concrete.Keywords: quarry dust, concrete, aggregates, compressive strength
Procedia PDF Downloads 2474537 Using of the Fractal Dimensions for the Analysis of Hyperkinetic Movements in the Parkinson's Disease
Authors: Sadegh Marzban, Mohamad Sobhan Sheikh Andalibi, Farnaz Ghassemi, Farzad Towhidkhah
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Parkinson's disease (PD), which is characterized by the tremor at rest, rigidity, akinesia or bradykinesia and postural instability, affects the quality of life of involved individuals. The concept of a fractal is most often associated with irregular geometric objects that display self-similarity. Fractal dimension (FD) can be used to quantify the complexity and the self-similarity of an object such as tremor. In this work, we are aimed to propose a new method for evaluating hyperkinetic movements such as tremor, by using the FD and other correlated parameters in patients who are suffered from PD. In this study, we used 'the tremor data of Physionet'. The database consists of fourteen participants, diagnosed with PD including six patients with high amplitude tremor and eight patients with low amplitude. We tried to extract features from data, which can distinguish between patients before and after medication. We have selected fractal dimensions, including correlation dimension, box dimension, and information dimension. Lilliefors test has been used for normality test. Paired t-test or Wilcoxon signed rank test were also done to find differences between patients before and after medication, depending on whether the normality is detected or not. In addition, two-way ANOVA was used to investigate the possible association between the therapeutic effects and features extracted from the tremor. Just one of the extracted features showed significant differences between patients before and after medication. According to the results, correlation dimension was significantly different before and after the patient's medication (p=0.009). Also, two-way ANOVA demonstrates significant differences just in medication effect (p=0.033), and no significant differences were found between subject's differences (p=0.34) and interaction (p=0.97). The most striking result emerged from the data is that correlation dimension could quantify medication treatment based on tremor. This study has provided a technique to evaluate a non-linear measure for quantifying medication, nominally the correlation dimension. Furthermore, this study supports the idea that fractal dimension analysis yields additional information compared with conventional spectral measures in the detection of poor prognosis patients.Keywords: correlation dimension, non-linear measure, Parkinson’s disease, tremor
Procedia PDF Downloads 2454536 Binary Logistic Regression Model in Predicting the Employability of Senior High School Graduates
Authors: Cromwell F. Gopo, Joy L. Picar
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This study aimed to predict the employability of senior high school graduates for S.Y. 2018- 2019 in the Davao del Norte Division through quantitative research design using the descriptive status and predictive approaches among the indicated parameters, namely gender, school type, academics, academic award recipient, skills, values, and strand. The respondents of the study were the 33 secondary schools offering senior high school programs identified through simple random sampling, which resulted in 1,530 cases of graduates’ secondary data, which were analyzed using frequency, percentage, mean, standard deviation, and binary logistic regression. Results showed that the majority of the senior high school graduates who come from large schools were females. Further, less than half of these graduates received any academic award in any semester. In general, the graduates’ performance in academics, skills, and values were proficient. Moreover, less than half of the graduates were not employed. Then, those who were employed were either contractual, casual, or part-time workers dominated by GAS graduates. Further, the predictors of employability were gender and the Information and Communications Technology (ICT) strand, while the remaining variables did not add significantly to the model. The null hypothesis had been rejected as the coefficients of the predictors in the binary logistic regression equation did not take the value of 0. After utilizing the model, it was concluded that Technical-Vocational-Livelihood (TVL) graduates except ICT had greater estimates of employability.Keywords: employability, senior high school graduates, Davao del Norte, Philippines
Procedia PDF Downloads 1584535 In-Context Meta Learning for Automatic Designing Pretext Tasks for Self-Supervised Image Analysis
Authors: Toktam Khatibi
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Self-supervised learning (SSL) includes machine learning models that are trained on one aspect and/or one part of the input to learn other aspects and/or part of it. SSL models are divided into two different categories, including pre-text task-based models and contrastive learning ones. Pre-text tasks are some auxiliary tasks learning pseudo-labels, and the trained models are further fine-tuned for downstream tasks. However, one important disadvantage of SSL using pre-text task solving is defining an appropriate pre-text task for each image dataset with a variety of image modalities. Therefore, it is required to design an appropriate pretext task automatically for each dataset and each downstream task. To the best of our knowledge, the automatic designing of pretext tasks for image analysis has not been considered yet. In this paper, we present a framework based on In-context learning that describes each task based on its input and output data using a pre-trained image transformer. Our proposed method combines the input image and its learned description for optimizing the pre-text task design and its hyper-parameters using Meta-learning models. The representations learned from the pre-text tasks are fine-tuned for solving the downstream tasks. We demonstrate that our proposed framework outperforms the compared ones on unseen tasks and image modalities in addition to its superior performance for previously known tasks and datasets.Keywords: in-context learning (ICL), meta learning, self-supervised learning (SSL), vision-language domain, transformers
Procedia PDF Downloads 854534 Phelipanche Ramosa (L. - Pomel) Control in Field Tomato Crop
Authors: G. Disciglio, F. Lops, A. Carlucci, G. Gatta, A. Tarantino, L. Frabboni, F. Carriero, F. Cibelli, M. L. Raimondo, E. Tarantino
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The Phelipanche ramosa is is an important crop whose cultivation in the Mediterranean basin is severely contained the phitoparasitic weed Phelipanche ramose. The semiarid regions of the world are considered the main center of this parasitic weed, where heavy infestation is due to the ability to produce high numbers of seeds (up to 500,000 per plant), that remain viable for extended period (more than 19 years). In this paper 12 treatments of parasitic weed control including chemical, agronomic, biological and biotechnological methods have been carried out. In 2014 a trial was performed at Foggia (southern Italy). on processing tomato (cv Docet), grown in field infested by Phelipanche ramosa, Tomato seedlings were transplant on May 5, 2014 on a clay-loam soil (USDA) fertilized by 100 kg ha-1 of N; 60 kg ha-1 of P2O5 and 20 kg ha-1 of S. Afterwards, top dressing was performed with 70 kg ha-1 of N. The randomized block design with 3 replicates was adopted. During the growing cycle of the tomato, at 56-78 and 92 days after transplantation, the number of parasitic shoots emerged in each pot was detected. At harvesting, on August 18, the major quantity-quality yield parameters were determined (marketable yield, mean weight, dry matter, pH, soluble solids and color of fruits). All data were subjected to analysis of variance (ANOVA), using the JMP software (SAS Institute Inc., Cary, NC, USA), and for comparison of means was used Tukey's test. Each treatment studied did not provide complete control against Phelipanche ramosa. However among the 12 tested methods, Fusarium, gliphosate, radicon biostimulant and Red Setter tomato cv (improved genotypes obtained by Tilling technology) proved to mitigate the virulence of the attacks of Phelipanche ramose. It is assumed that these effects can be improved by combining some of these treatments each other, especially for a gradual and continuing reduction of the “seed bank” of the parasite in the soil.Keywords: control methods, Phelipanche ramosa, tomato crop, mediterranean basin
Procedia PDF Downloads 5684533 Computational Fluid Dynamics Analysis of Convergent–Divergent Nozzle and Comparison against Theoretical and Experimental Results
Authors: Stewart A. Keir, Faik A. Hamad
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This study aims to use both analytical and experimental methods of analysis to examine the accuracy of Computational Fluid Dynamics (CFD) models that can then be used for more complex analyses, accurately representing more elaborate flow phenomena such as internal shockwaves and boundary layers. The geometry used in the analytical study and CFD model is taken from the experimental rig. The analytical study is undertaken using isentropic and adiabatic relationships and the output of the analytical study, the 'shockwave location tool', is created. The results from the analytical study are then used to optimize the redesign an experimental rig for more favorable placement of pressure taps and gain a much better representation of the shockwaves occurring in the divergent section of the nozzle. The CFD model is then optimized through the selection of different parameters, e.g. turbulence models (Spalart-Almaras, Realizable k-epsilon & Standard k-omega) in order to develop an accurate, robust model. The results from the CFD model can then be directly compared to experimental and analytical results in order to gauge the accuracy of each method of analysis. The CFD model will be used to visualize the variation of various parameters such as velocity/Mach number, pressure and turbulence across the shock. The CFD results will be used to investigate the interaction between the shock wave and the boundary layer. The validated model can then be used to modify the nozzle designs which may offer better performance and ease of manufacture and may present feasible improvements to existing high-speed flow applications.Keywords: CFD, nozzle, fluent, gas dynamics, shock-wave
Procedia PDF Downloads 2364532 Study on the Stability of Large Space Expandable Parabolic Cylindrical Antenna
Authors: Chuanzhi Chen, Wenjing Yu
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Parabolic cylindrical deployable antenna has the characteristics of wide cutting width, strong directivity, high gain, and easy automatic beam scanning. While, due to its large size, high flexibility, and strong coupling, the deployment process of parabolic cylindrical deployable antenna presents such problems as unsynchronized deployment speed, large local deformation and discontinuous switching of deployment state. A large deployable parabolic cylindrical antenna is taken as the research object, and the problem of unfolding process instability of cylindrical antenna is studied in the paper, which is caused by multiple factors such as multiple closed loops, elastic deformation, motion friction, and gap collision. Firstly, the multi-flexible system dynamics model of large-scale parabolic cylindrical antenna is established to study the influence of friction and elastic deformation on the stability of large multi-closed loop antenna. Secondly, the evaluation method of antenna expansion stability is studied, and the quantitative index of antenna configuration design is proposed to provide a theoretical basis for improving the overall performance of the antenna. Finally, through simulation analysis and experiment, the development dynamics and stability of large-scale parabolic cylindrical antennas are verified by in-depth analysis, and the principles for improving the stability of antenna deployment are summarized.Keywords: multibody dynamics, expandable parabolic cylindrical antenna, stability, flexible deformation
Procedia PDF Downloads 1514531 Effect of Crown Gall and Phylloxera Resistant Rootstocks on Grafted Vitis Vinifera CV. Sultana Grapevine
Authors: Hassan Mahmoudzadeh
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The bacterium of Agrobacterium vitis causes crown and root gall disease, an important disease of grapevine, Vitis vinifera L. Also, Phylloxera is one of the most important pests in viticulture. Grapevine rootstocks were developed to provide increased resistance to soil-borne pests and diseases, but rootstock effects on some traits remain unclear. The interaction between rootstock, scion and environment can induce different responses to the grapevine physiology. 'Sultsna' (Vitis vinifera L.) is one of the most valuable raisin grape cultivars in Iran. Thus, the aim of this study was to determine the rootstock effect on the growth characteristics and yield components and quality of 'Sultana' grapevine grown in the Urmia viticulture region. The experimental design was completely randomized blocks, with four treatments, four replicates and 10 vines per plot. The results show that all variables evaluated were significantly affected by the rootstock. The Sultana/110R and Sultana/Nazmieh were among other combinations influenced by the year and had a higher significant yield/vine (13.25 and 12.14, respectively). Indeed, they were higher than that of Sultana/5BB (10.56 kg/vine) and Sultana/Spota (10.25 kg/vine). The number of clusters per burst bud and per vine and the weight of clusters were affected by the rootstock as well. Pruning weight/vine, yield/pruning weight, leaf area/vine and leaf area index are variables related to the physiology of grapevine, which was also affected by the rootstocks. In general, rootstocks had adapted well to the environment where the experiment was carried out, giving vigor and high yield to Sultana grapevine, which means that they may be used by grape growers in this region. In sum, the study found the best rootstocks for 'Sultana' to be Nazmieh and 110R in terms of root and shoot growth. However, the choice of the right rootstock depends on various aspects, such as those related to soil characteristics, climate conditions, grape varieties, and even clones, and production purposes.Keywords: grafting, vineyards, grapevine, succeptability
Procedia PDF Downloads 1324530 Portuguese Guitar Strings Characterization and Comparison
Authors: P. Serrão, E. Costa, A. Ribeiro, V. Infante
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The characteristic sonority of the Portuguese guitar is in great part what makes Fado so distinguishable from other traditional song styles. The Portuguese guitar is a pear-shaped plucked chordophone with six courses of double strings. This study compares the two types of plain strings available for Portuguese guitar and used by the musicians. One is stainless steel spring wire, the other is high carbon spring steel (music wire). Some musicians mention noticeable differences in sound quality between these two string materials, such as a little more brightness and sustain in the steel strings. Experimental tests were performed to characterize string tension at pitch; mechanical strength and tuning stability using the universal testing machine; dimensional control and chemical composition analysis using the scanning electron microscope. The string dynamical behaviour characterization experiments, including frequency response, inharmonicity, transient response, damping phenomena and were made in a monochord test set-up designed and built in-house. Damping factor was determined for the fundamental frequency. As musicians are able to detect very small damping differences, an accurate a characterization of the damping phenomena for all harmonics was necessary. With that purpose, another improved monochord was set and a new system identification methodology applied. Due to the complexity of this task several adjustments were necessary until obtaining good experimental data. In a few cases, dynamical tests were repeated to detect any evolution in damping parameters after break-in period when according to players experience a new string sounds gradually less dull until reaching the typically brilliant timbre. Finally, each set of strings was played on one guitar by a distinguished player and recorded. The recordings which include individual notes, scales, chords and a study piece, will be analysed to potentially characterize timbre variations.Keywords: damping factor, music wire, portuguese guitar, string dynamics
Procedia PDF Downloads 5544529 Nations in Labour: Incorporating National Narratives in Sociological Models of Cultural Labour
Authors: Anna Lytvynova
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This essay presents labour as a performatively national phenomenon from a cultural perspective. Considering Engels’ proposition of labour as the epicentre of development of social structures and communities, it theorizes the formation and sustainment of group identities through labour identities. Taking labour in the cultural sector as the starting point case study, the essay further enunciates such labour and labour identity as a form of engaged citizenship. In doing so, this piece hopes to arrive at a potential contemporary understanding of labour as having a central and dynamic role in cultural organization and citizenship. A parallel goal is to de-link sociological models of cultural labor from narratives of art and culture as something that stands separate from the 'real world' and the economy and exists in precarity. Combining discourse from cultural sociology, performance studies, and economics and grounding it in historical archive, the essay makes a primarily discursive theoretical contribution. Taking North American theatre organizations as the exemplifying starting point, this project positions cultural workers not solely as workers in a professional industry but as active citizen-subjects who are deeply involved in their society’s democratic processes. The resulting discourse can be used to shape more effective labour policies, as well as help art and cultural organizations find more effective organizational structures to engage the arts in the economic, political, and social spheres.Keywords: arts labour, cultural sociology, national identity, performativity
Procedia PDF Downloads 1314528 Sense of Involvement and Support in Persons with Cognitive Decline in Ordinary Dwelling
Authors: Annika Kjallman Alm, Ove Hellzen, Malin Rising-Holmstrom
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Worldwide, the number of people who are living with dementia is increasing because of an aging population, which leads to increased financial and social costs, including reduced quality of life for people with dementia and their care partners. Most people who have dementia reside in the community. Aging in place could be described as having the health and social supports and services you need to live safely and independently in your home or your society for as long as you wish and are able. People with dementia are not different than people without dementia where they want to remain at home, if possible, with a sense of familiarity and engagement in typical everyday activities. So how do persons with dementia or cognitive decline see their possibilities to be socially involved and experience support? The aim of this study was to explore persons with cognitive decline's sense of involvement and support living in the ordinary dwelling. The study was approved by the Ethical Review Authority in Sweden prior to the interviews. Interviews were conducted with 20 persons living at home, either alone or in a relationship. The persons had perceived cognitive decline; some were under investigation or already had a diagnose of early dementia. Thematic analysis was used to identify, analyze, and report patterns within the data. Researchers extracted three main themes through participants’ interviews: a) Importance of social involvement with family and friends. b) Hindrances for social involvement. c) Struggling mentally with a new life situation. Results found that going to activity centers, staying involved, and meeting friends and family enhanced the sense of involvement and support. There were also hindrances to a sense of involvement and support as they struggled with the diagnose and the changes in daily life, such as physical problems, mental problems, or economic issues. The mental struggle of accepting the cognitive decline and the changes in daily life it brought was also an issue for some of the participants. A multidimensional support should be provided by the community to enable persons with cognitive decline to stay involved in family and community in the comfort of their own homes.Keywords: aging in place, cognitive decline, dementia, sense of involvement
Procedia PDF Downloads 1454527 Analysis of Cascade Control Structure in Train Dynamic Braking System
Authors: B. Moaveni, S. Morovati
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In recent years, increasing the usage of railway transportations especially in developing countries caused more attention to control systems railway vehicles. Consequently, designing and implementing the modern control systems to improve the operating performance of trains and locomotives become one of the main concerns of researches. Dynamic braking systems is an important safety system which controls the amount of braking torque generated by traction motors, to keep the adhesion coefficient between the wheel-sets and rail road in optimum bound. Adhesion force has an important role to control the braking distance and prevent the wheels from slipping during the braking process. Cascade control structure is one of the best control methods for the wide range of industrial plants in the presence of disturbances and errors. This paper presents cascade control structure based on two forward simple controllers with two feedback loops to control the slip ratio and braking torque. In this structure, the inner loop controls the angular velocity and the outer loop control the longitudinal velocity of the locomotive that its dynamic is slower than the dynamic of angular velocity. This control structure by controlling the torque of DC traction motors, tries to track the desired velocity profile to access the predefined braking distance and to control the slip ratio. Simulation results are employed to show the effectiveness of the introduced methodology in dynamic braking system.Keywords: cascade control, dynamic braking system, DC traction motors, slip control
Procedia PDF Downloads 3674526 Gender and Seniority Differences among Service Organizations' Employees: Motivation, Commitment, and Burnout
Authors: K. Michael, G. Yanay-Ventura
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Objectives: It is well established that employees are the essence of the organization. Employees' personal characteristics and emotional state may decrease or increase organizational performance. Therefore, organizations should enhance employees' well-being. The present study examined gender and seniority differences in three factors of employees' well-being: motivation, commitment, and burnout. Methods: Participants in this quantitative cross-sectional study were 400 service organization employees aged 19-71 (Mean=29.94; SD=10.25). Regarding gender, 59.7% were women, and regarding seniority, 66.9% were less than two years in the organization. All participants completed questionnaires evaluating motivation, sense of organizational commitment (affective, continuance), and level of burnout (emotional exhaustion, depersonalization, personal accomplishment). Data were analyzed using IBM-SPSS (version 25) through independent-sample t-tests. Results: Women were less motivated and felt less affective commitment toward the organization than men. They also felt more burnout than men in terms of emotional exhaustion and depersonalization. Additionally, employees in lower seniority levels felt less affective commitment toward the organization than employees in higher seniority levels. They also felt more burnout than employees in higher seniority levels in terms of emotional exhaustion, depersonalization, and personal accomplishment. Conclusions: The findings suggest that women and employees in lower seniority levels experience more vulnerable emotions in service organizations. Therefore, strategies for enhancing their well-being are recommended.Keywords: burnout, gender and seniority differences, motivation, organizational commitment
Procedia PDF Downloads 1364525 HPTLC Fingerprint Profiling of Protorhus longifolia Methanolic Leaf Extract and Qualitative Analysis of Common Biomarkers
Authors: P. S. Seboletswe, Z. Mkhize, L. M. Katata-Seru
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Protorhus longifolia is known as a medicinal plant that has been used traditionally to treat various ailments such as hemiplegic paralysis, blood clotting related diseases, diarrhoea, heartburn, etc. The study reports a High-Performance Thin Layer Chromatography (HPTLC) fingerprint profile of Protorhus longifolia methanolic extract and its qualitative analysis of gallic acid, rutin, and quercetin. HPTLC analysis was achieved using CAMAG HPTLC system equipped with CAMAG automatic TLC sampler 4, CAMAG Automatic Developing Chamber 2 (ADC2), CAMAG visualizer 2, CAMAG Thin Layer Chromatography (TLC) scanner and visionCATS CAMAG HPTLC software. Mobile phase comprising toluene, ethyl acetate, formic acid (21:15:3) was used for qualitative analysis of gallic acid and revealed eight peaks while the mobile phase containing ethyl acetate, water, glacial acetic acid, formic acid (100:26:11:11) for qualitative analysis of rutin and quercetin revealed six peaks. HPTLC sillica gel 60 F254 glass plates (10 × 10) were used as the stationary phase. Gallic acid was detected at the Rf = 0.35; while rutin and quercetin were not evident in the extract. Further studies will be performed to quantify gallic acid in Protorhus longifolia leaves and also identify other biomarkers.Keywords: biomarkers, fingerprint profiling, gallic acid, HPTLC, Protorhus longifolia
Procedia PDF Downloads 1494524 Estimating the Impact of Appliance Energy Efficiency Improvement on Residential Energy Demand in Tema City, Ghana
Authors: Marriette Sakah, Samuel Gyamfi, Morkporkpor Delight Sedzro, Christoph Kuhn
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Ghana is experiencing rapid economic development and its cities command an increasingly dominant role as centers of both production and consumption. Cities run on energy and are extremely vulnerable to energy scarcity, energy price escalations and health impacts of very poor air quality. The overriding concern in Ghana and other West African states is bridging the gap between energy demand and supply. Energy efficiency presents a cost-effective solution for supply challenges by enabling more coverage with current power supply levels and reducing the need for investment in additional generation capacity and grid infrastructure. In Ghana, major issues for energy policy formulation in residential applications include lack of disaggregated electrical energy consumption data and lack of thorough understanding with regards to socio-economic influences on energy efficiency investment. This study uses a bottom up approach to estimate baseline electricity end-use as well as the energy consumption of best available technologies to enable estimation of energy-efficiency resource in terms of relative reduction in total energy use for Tema city, Ghana. A ground survey was conducted to assess the probable consumer behavior in response to energy efficiency initiatives to enable estimation of the amount of savings that would occur in response to specific policy interventions with regards to funding and incentives provision targeted at households. Results show that 16% - 54% reduction in annual electricity consumption is reasonably achievable depending on the level of incentives provision. The saved energy could supply 10000 - 34000 additional households if the added households use only best available technology. Political support and consumer awareness are necessary to translate energy efficiency resources into real energy savings.Keywords: achievable energy savings, energy efficiency, Ghana, household appliances
Procedia PDF Downloads 2194523 Taguchi-Based Surface Roughness Optimization for Slotted and Tapered Cylindrical Products in Milling and Turning Operations
Authors: Vineeth G. Kuriakose, Joseph C. Chen, Ye Li
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The research follows a systematic approach to optimize the parameters for parts machined by turning and milling processes. The quality characteristic chosen is surface roughness since the surface finish plays an important role for parts that require surface contact. A tapered cylindrical surface is designed as a test specimen for the research. The material chosen for machining is aluminum alloy 6061 due to its wide variety of industrial and engineering applications. HAAS VF-2 TR computer numerical control (CNC) vertical machining center is used for milling and HAAS ST-20 CNC machine is used for turning in this research. Taguchi analysis is used to optimize the surface roughness of the machined parts. The L9 Orthogonal Array is designed for four controllable factors with three different levels each, resulting in 18 experimental runs. Signal to Noise (S/N) Ratio is calculated for achieving the specific target value of 75 ± 15 µin. The controllable parameters chosen for turning process are feed rate, depth of cut, coolant flow and finish cut and for milling process are feed rate, spindle speed, step over and coolant flow. The uncontrollable factors are tool geometry for turning process and tool material for milling process. Hypothesis testing is conducted to study the significance of different uncontrollable factors on the surface roughnesses. The optimal parameter settings were identified from the Taguchi analysis and the process capability Cp and the process capability index Cpk were improved from 1.76 and 0.02 to 3.70 and 2.10 respectively for turning process and from 0.87 and 0.19 to 3.85 and 2.70 respectively for the milling process. The surface roughnesses were improved from 60.17 µin to 68.50 µin, reducing the defect rate from 52.39% to 0% for the turning process and from 93.18 µin to 79.49 µin, reducing the defect rate from 71.23% to 0% for the milling process. The purpose of this study is to efficiently utilize the Taguchi design analysis to improve the surface roughness.Keywords: surface roughness, Taguchi parameter design, CNC turning, CNC milling
Procedia PDF Downloads 1604522 Metagovernance and Sustainable Development Goals: Importance of Sustainable Policies and Democratic Institutions
Authors: Ghulam Rasool Madni
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Global economies are prioritizing the attainment of Sustainable Development Goals (SDGs) for well-being of their people. An emphasis lies on the concept of metagovernance when contemplating the role of government in SDGs, especially in the context of its influence and guidance. Existing literature acknowledges the pivotal role of metagovernance in achieving the SDGs, but aspects of metagovernance unclear that are important for 17 SDGs. Using data from 41 countries, a comparative analysis is conducted for the year 2022. Utilizing a multiple regression analysis, the impact of different dimensions of metagovernance to achieve SDGs is explored, with a particular focus on sustainable policies, strategic capacity, policy coherence, democratic institutions, reflexivity, and adaptation. It is found that sustainable policies have a positive and significant relationship with different SDGs, including no poverty, zero hunger, health, sanitation and clean water, affordable and clean energy, decent work and economic growth, industry, innovation and infrastructure, reduced inequalities while democratic institutions also have a positive relationship with no poverty, good health and well-being, quality education, gender equality, clean water and sanitation, clean and affordable energy, and peace, justice, and strong institutions in these countries. Policymakers are suggested to ensure that sustainable policies are backed by legislation to provide them with a strong legal foundation. It is suggested to develop a long-term vision for sustainability that goes beyond short-term political cycles. Economies are encouraged to invest in building the capacity of government agencies, civil society organizations, and other stakeholders to effectively implement sustainable policies. Moreover, democratic institutions may be established through a constitution providing a solid foundation for democratic governance, including protection of human rights, separation of powers, and mechanisms for accountability and transparency.Keywords: metagovernance, sustainable development goals, sustainable policies, democratic institutions
Procedia PDF Downloads 254521 Inpatient Neonatal Deaths in Rural Uganda: A Retrospective Comparative Mortality Study of Labour Ward versus Community Admissions
Authors: Najade Sheriff, Malaz Elsaddig, Kevin Jones
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Background: Death in the first month of life accounts for an increasing proportion of under-five mortality. Advancement to reduce this number is being made across the globe; however, progress is slowest in sub-Saharan Africa. Objectives: The study aims to identify differences between neonatal deaths of inpatient babies born in a hospital facility in rural Uganda to those of neonates admitted from the community and to explore whether they can be used to risk stratify neonatal admissions. Results: A retrospective chart review was conducted on records for neonates admitted to the Special Care Baby Unit (SCBU) Kitovu Hospital from 1st July 2016 to 21st July 2017. A total of 442 babies were admitted and the overall neonatal mortality was 24.8% (40% inpatient, 37% community, 23% hospital referrals). 40% of deaths occurred within 24 hours of admission and the majority were male (63%). 43% of babies were hypothermic upon admission, a significantly greater proportion of which were inpatient babies born in labour ward (P=0.0025). Intrapartum related death accounted for ½ of all inpatient babies whereas complications of prematurity were the predominant cause of death in the community group (37%). Severe infection does not seem like a significant factor of mortality for inpatients (2%) as it does for community admissions (29%). Furthermore, with 52.5% of community admissions weighing < 1500g, very low birth weight (VLBW) may be a significant risk factor for community neonatal death. Conclusion: The neonatal mortality rate in this study is high, and the leading causes of death are all largely preventable. A high rate of inpatient birth asphyxiation indicates the need for good quality facility-based perinatal care as well as a greater focus on the management of hypothermia, such as Kangaroo care. Moreover, a reduction in preterm deliveries is necessary to reduce associated comorbidities, and monitoring for signs of infection is especially important for community admissions.Keywords: community, mortality, newborn, Uganda
Procedia PDF Downloads 1944520 Feasibility Study of a Solar Farm Project with an Executive Approach
Authors: Amir Reza Talaghat
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Since 2015, a new approach and policy regarding energy resources protection and using renewable energies has been started in Iran which was developing new projects. Investigating about the feasibility study of these new projects helped to figure out five steps to prepare an executive feasibility study of the concerned projects, which are proper site selections, authorizations, design and simulation, economic study and programming, respectively. The results were interesting and essential for decision makers and investors to start implementing of these projects in reliable condition. The research is obtained through collection and study of the project's documents as well as recalculation to review conformity of the results with GIS data and the technical information of the bidders. In this paper, it is attempted to describe the result of the performed research by describing the five steps as an executive methodology, for preparing a feasible study of installing a 10 MW – solar farm project. The corresponding results of the research also help decision makers to start similar projects is explained in this paper as follows: selecting the best location for the concerned PV plant, reliable and safe conditions for investment and the required authorizations to start implementing the solar farm project in the concerned region, selecting suitable component to achieve the best possible performance for the plant, economic profit of the investment, proper programming to implement the project on time.Keywords: solar farm, solar energy, execution of PV power plant PV power plant
Procedia PDF Downloads 1854519 Impact of Joule Heating on the Electrical Conduction Behavior of Carbon Composite Laminates under Simulated Lightning Strike
Authors: Hong Yu, Dirk Heider, Suresh Advani
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Increasing demands for high strength and lightweight materials in aircraft industry prompted the wide use of carbon composites in recent decades. Carbon composite laminates used on aircraft structures are subject to lightning strikes. Unlike its metal/alloy counterparts, carbon fiber reinforced composites demonstrate smaller electrical conductivity, yielding more severe damages due to Joule heating. The anisotropic nature of composite laminates makes the electrical and thermal conduction within carbon composite laminates even more complicated. Good understanding of the electrical conduction behavior of carbon composites is the key to effective lightning protection design. The goal of this study is to numerically and experimentally investigate the impact of ultra-high temperature induced by simulated lightning strike on the electrical conduction of carbon composites. A lightning simulator is designed to apply standard lightning current waveform to composite laminates. Multiple carbon composite laminates made from IM7 and AS4 carbon fiber are tested and the transient resistance data is recorded. A microstructure based resistor network model is developed to describe the electrical and thermal conduction behavior, with consideration of temperature dependent material properties. Material degradations such as thermal and electrical breakdown are also modeled to include the effect of high current and high temperature induced by lightning strikes. Good match between the simulation results and experimental data indicates that the developed model captures the major conduction mechanisms. A parametric study is then conducted using the validated model to investigate the effect of system parameters such as fiber volume fraction, inter-ply interface quality, and lightning current waveforms.Keywords: carbon composite, joule heating, lightning strike, resistor network
Procedia PDF Downloads 2294518 Comparative Study of Ni Catalysts Supported by Silica and Modified by Metal Additions Co and Ce for The Steam Reforming of Methane
Authors: Ali Zazi, Ouiza Cherifi
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The Catalysts materials Ni-SiO₂, Ni-Co-SiO₂ and Ni-Ce-SiO₂ were synthetized by classical method impregnation and supported by silica. This involves combing the silica with an adequate rate of the solution of nickel nitrates, or nickel nitrate and cobalt nitrate, or nickel nitrate and cerium nitrate, mixed, dried and calcined at 700 ° c. These catalysts have been characterized by different physicochemical analysis techniques. The atomic absorption spectrometry indicates that the real contents of nickel, cerium and cobalt are close to the theoretical contents previously assumed, which let's say that the nitrate solutions have impregnated well the silica support. The BET results show that the surface area of the specific surfaces decreases slightly after impregnation with nickel nitrates or Co and Ce metals and a further slight decrease after the reaction. This is likely due to coke deposition. X-ray diffraction shows the presence of the different SiO₂ and NiO phases for all catalysts—theCoO phase for that promoted by Co and the Ce₂O₂ phase for that promoted by Ce. The methane steam reforming reaction was carried out on a quartz reactor in a fixed bed. Reactants and products of the reaction were analyzed by a gas chromatograph. This study shows that the metal addition of Cerium or Cobalt improves the majority of the catalytic performance of Ni for the steam reforming reaction of methane. And we conclude the classification of our Catalysts in order of decreasing activity and catalytic performances as follows: Ni-Ce / SiO₂ >Ni-Co / SiO₂> Ni / SiO₂ .Keywords: cerium, cobalt, heterogeneous catalysis, hydrogen, methane, steam reforming, synthesis gas
Procedia PDF Downloads 1984517 Functional Significance of Qatari Camels Milk: Antioxidant Content and Antimicrobial Activity of Protein Fractions
Authors: Tahra ElObeid, Omnya Ahmed, Reem Al-Sharshani, Doaa Dalloul, Jannat Alnattei
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Background: Camelus dormedarius camels are also called ‘the Arabian camels’ and are present in the desert area of North Africa and the Middle East. Recently, camel’s milk has a great attention globally because of their proteins and peptides that have been reported to be beneficial for the health and in the management of many diseases. Objectives: This study was designed to investigate the antioxidant, antimicrobial activity and to evaluate the total phenolic content of camel’s milk proteins in Qatar. Methods: Fresh two camel’s milk samples from Omani breed and called Muhajer (camel’s milk A and B) were collected on the 1st of the December. Both samples were from the same location Al- Shahaniyah, Doha, Qatar, but from different local private farms and feeding system. Camel’s milk A and B were defatted by centrifugation and their proteins were extracted by acid and thermal precipitation. The antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Total phenolic compound (TPC) was evaluated by Folin-Ciocalteu reagent (FCR). On the other hand, the antimicrobial activity against eight different type of pathogenic bacteria was evaluated by disc diffusion method and the zone of inhibition was measured. Results: The of the total phenolic content of whole milk in both camel’s milk A and B were significantly the highest among the protein extracts. The % of the DPPH radical inhibition of casein protein in both camel’s milk A and B were significantly the highest among the protein extracts. In this study, there were marked changes in the antibacterial activity in the different camel milk protein extracts. All extracts showed bacterial overgrowth. Conclusion: The antioxidant activity of the camel milk protein extracts correlated to their unique phenolic compounds and bioactive protein peptides. The antimicrobial activity was not detected perhaps due to the technique, the quality, or the extraction method. Overall, camel's milk exhibits a high antioxidant activity, which is responsible for many health benefits besides the nutritional values.Keywords: camels milk, antioxidant content, antimicrobial activity, proteins, Qatar
Procedia PDF Downloads 2164516 Institutional Effectiveness in Fostering Student Retention and Success in First Year
Authors: Naziema B. Jappie
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The objective of this study is to examine the relationship between college readiness characteristics and learning outcome assessment scores. About this, it is important to examine the first-year retention and success rate. In order to undertake this study, it will be necessary to look at proficiency levels on general and domain-specific knowledge and skills reflected on national benchmark test scores (NBT), in-college interventions and course-taking patterns. Preliminary results based on data from more than 1000 students suggest that there is a positive association between NBT scores and students’ 1st-year college GPA and their retention status. For example, 63% of students with a proficient level of math skills in the NBT had the highest level of GPA at the end of 1st-year of college in comparison to 56% of those who started with a primary or intermediate level, respectively. The retention rates among those with proficiency levels were also higher than those with basic or intermediate levels (98% vs. 93% and 88%, respectively). By the end of 3rd year in college, students with intermediate or proficient entering NBT math skills had 7% and 8% of dropout rate, compared to 14% for those started at primary level; a greater percentage of students qualified by the end of 3rd-year qualified among proficient students than that among intermediate or basic level students (50% vs. 44% and 27% respectively). The findings of this study added knowledge to the field in South Africa and are expected to help stakeholders and policymakers to better understand college learning and challenges for students with disadvantaged backgrounds and provide empirical evidence in support of related practices and policies.Keywords: assessment, data analysis, performance, proficiency, policy, student success
Procedia PDF Downloads 1374515 Energy Conservation in Heat Exchangers
Authors: Nadia Allouache
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Energy conservation is one of the major concerns in the modern high tech era due to the limited amount of energy resources and the increasing cost of energy. Predicting an efficient use of energy in thermal systems like heat exchangers can only be achieved if the second law of thermodynamics is accounted for. The performance of heat exchangers can be substantially improved by many passive heat transfer augmentation techniques. These letters permit to improve heat transfer rate and to increase exchange surface, but on the other side, they also increase the friction factor associated with the flow. This raises the question of how to employ these passive techniques in order to minimize the useful energy. The objective of this present study is to use a porous substrate attached to the walls as a passive enhancement technique in heat exchangers and to find the compromise between the hydrodynamic and thermal performances under turbulent flow conditions, by using a second law approach. A modified k- ε model is used to simulating the turbulent flow in the porous medium and the turbulent shear flow is accounted for in the entropy generation equation. A numerical modeling, based on the finite volume method is employed for discretizing the governing equations. Effects of several parameters are investigated such as the porous substrate properties and the flow conditions. Results show that under certain conditions of the porous layer thickness, its permeability, and its effective thermal conductivity the minimum rate of entropy production is obtained.Keywords: second law approach, annular heat exchanger, turbulent flow, porous medium, modified model, numerical analysis
Procedia PDF Downloads 2904514 Land Use/Land Cover Mapping Using Landsat 8 and Sentinel-2 in a Mediterranean Landscape
Authors: Moschos Vogiatzis, K. Perakis
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Spatial-explicit and up-to-date land use/land cover information is fundamental for spatial planning, land management, sustainable development, and sound decision-making. In the last decade, many satellite-derived land cover products at different spatial, spectral, and temporal resolutions have been developed, such as the European Copernicus Land Cover product. However, more efficient and detailed information for land use/land cover is required at the regional or local scale. A typical Mediterranean basin with a complex landscape comprised of various forest types, crops, artificial surfaces, and wetlands was selected to test and develop our approach. In this study, we investigate the improvement of Copernicus Land Cover product (CLC2018) using Landsat 8 and Sentinel-2 pixel-based classification based on all available existing geospatial data (Forest Maps, LPIS, Natura2000 habitats, cadastral parcels, etc.). We examined and compared the performance of the Random Forest classifier for land use/land cover mapping. In total, 10 land use/land cover categories were recognized in Landsat 8 and 11 in Sentinel-2A. A comparison of the overall classification accuracies for 2018 shows that Landsat 8 classification accuracy was slightly higher than Sentinel-2A (82,99% vs. 80,30%). We concluded that the main land use/land cover types of CLC2018, even within a heterogeneous area, can be successfully mapped and updated according to CLC nomenclature. Future research should be oriented toward integrating spatiotemporal information from seasonal bands and spectral indexes in the classification process.Keywords: classification, land use/land cover, mapping, random forest
Procedia PDF Downloads 1304513 Arsenic Speciation in Cicer arietinum: A Terrestrial Legume That Contains Organoarsenic Species
Authors: Anjana Sagar
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Arsenic poisoned ground water is a major concern in South Asia. The arsenic enters the food chain not only through drinking but also by using arsenic polluted water for irrigation. Arsenic is highly toxic in its inorganic forms; however, organic forms of arsenic are comparatively less toxic. In terrestrial plants, inorganic form of arsenic is predominantly found; however, we found that significant proportion of organic arsenic was present in root and shoot of a staple legume, chickpea (Cicer arientinum L) plants. Chickpea plants were raised in pot culture on soils spiked with arsenic ranging from 0-70 mg arsenate per Kg soil. Total arsenic concentrations of chickpea shoots and roots were determined by inductively coupled plasma-mass-spectrometry (ICP-MS) ranging from 0.76 to 20.26, and 2.09 to 16.43 µg g⁻¹ dry weight, respectively. Information on arsenic species was acquired by methanol/water extraction method, with arsenic species being analyzed by high-performance liquid chromatography (HPLC) coupled with ICP-MS. Dimethylarsinic acid (DMA) was the only organic arsenic species found in amount from 0.02 to 3.16 % of total arsenic shoot concentration and 0 to 6.93 % of total arsenic root concentration, respectively. To investigate the source of the organic arsenic in chickpea plants, arsenic species in the rhizosphere of soils of plants were also examined. The absence of organic arsenic in soils would suggest the possibility of formation of DMA in plants. The present investigation provides useful information for better understanding of distribution of arsenic species in terrestrial legume plants.Keywords: arsenic, arsenic speciation, dimethylarsinic acid, organoarsenic
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